Final Report Appropriate Composting Technology Project PSF 2006

8/14/2019 Final Report Appropriate Composting Technology Project PSF 2006

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FINAL REPORT(2003-2006)

APPROPRIATE COMPOSTING TECHNOLOGYFOR RICE-WHEAT SYSTEM IN NORMAL AND

SALT-AFFECTED SOILS

Conducted underPAKISTAN SCIENCE FOUNDATION

Grant No. (R&D/P-SSRI/AGRI. 161)

Compiled by

DR. NAZIR HUSSAIN(Agricultural Chemist / Principal Investigator)

Dr. Ghulam Sarwar

Mr. Abdul Rasul Naseem

Government of Punjab, Agricultural DepartmentSoil Salinity Research Institute, (SSRI)

Pindi Bhattian (Punjab) Pakistan

July, 2006


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FINAL REPORT(2003-2006)

APPROPRIATE COMPOSTING TECHNOLOGYFOR RICE-WHEAT SYSTEM IN NORMAL AND

SALT-AFFECTED SOILS

Pakistan Science Foundation (PSF) Islamabad,

Soil Salinity Research Institute, (SSRI)

Pindi Bhattian (Punjab) Pakistan

July, 2006

Ways to Contacts:

DR. NAZIR HUSSAIN

(Agricultural Chemist / Principal Investigator)

Soil Salinity Research Institute, (SSRI)Pindi Bhattian (Punjab) PakistanPhone No: 0547-531573, 531376Fax No: 0547-531576E-mail: [email protected] / [email protected]


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CONTENTS

Sr. No. Titles and subtitles Page

1 Summary 7

2 Detailed Report 10

2.1 Project Title 10

2.2 Report Period 10

2.3 Introduction 10

2.4 Experimental Procedures 14

2.5 Results 17

2.6 Discussion 20

2.7 Conclusions 33

2.8 Need for additional research 34

2.9 Publications 35

2.10 Ph.D. Degrees 35

2.11 List of Scientists 35-36

2.12 Bibliography 37

2.13 Tables(1-40) 40-68


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LIST OF TABLESSr. # Title of tables Page

1 Analysis of Different Organic Materials Used in Various Experiments 40

2 Original soil analysis of pot and field experiments 41

3 Nutrient Supplementation to first rice crop (2003) through Compost inNormal Soils (field experiment)

42

4 Nutrient Supplementation to first wheat crop (2003-04) through Compostin Normal Soils (field experiment)

42

5 Nutrient Supplementation to second rice crop (2004) through Compost inNormal Soils (field experiment) 43

6 Nutrient Supplementation to second rice crop (2004) through Compost inNormal Soils (field experiment)

43

7 Effect of compost on soil properties in nutrient supplementation after firstrice crop (field experiment)

44

8 Effect of compost on soil properties in nutrient supplementation afterfirst wheat crop (field experiment)

44

9 Effect of compost on soil properties in nutrient supplementation aftersecond rice crop (field experiment)

45

10 Effect of compost on soil properties in nutrient supplementationafter second wheat crop (field experiment)

45

11 Nutrient Supplementation to first rice crop (2003) through Compost in NorSoils (pot experiment)

46

12 Nutrient Supplementation to first wheat crop (2003-04) through Compostin Normal Soils (pot experiment)

46

13 Nutrient Supplementation to second rice crop (2004) through Compost inNormal Soils (pot experiment)

47

14 Nutrient Supplementation to second wheat crop (2004-05) through 47


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Compost in Normal Soils (pot experiment)

15 Effect of compost on soil properties in nutrient supplementation after firstrice crop (pot experiment)

48

16 Effect of compost on soil properties in nutrient supplementation after firstwheat crop (pot experiment)

48

17 Effect of compost on soil properties in nutrient supplementation aftersecond rice crop (pot experiment)

49

18 Effect of compost on soil properties in nutrient supplementationafter second wheat crop (pot experiment)

49

19 Effect of Different Levels of Compost and Gypsum on Yield and YieldParameters of first Rice crop (2003) in Saline Sodic Soil (Field Experiment)

50

20 Effect of Different Levels of Compost and Gypsum on Yield and YieldParameters of first wheat crop (2003-04) in Saline Sodic Soil (FieldExperiment)

50

21 Effect of Different Levels of Compost and Gypsum on Yield andyield Parameters of Second Rice crop (2004) in Saline Sodic Soil (FieldExperiment)

51

22 Effect of Different Levels of Compost and Gypsum on Yield andyield Parameters of second wheat crop (2004-05) in Saline Sodic Soil (FieldExperiment)

51

23 Effect of Different Levels of Compost and Gypsum on ChemicalProperties of Saline Sodic Soil after first Rice crop (Field Experiment)

52

24 Effect of Different Levels of Compost and Gypsum on Chemical Propertiesof Saline Sodic Soil after first wheat crop(Field Experiment)

53

25 Effect of Different Levels of Compost and Gypsum on Chemical Propertiesof Saline Sodic Soil after Second Rice crop (Field Experiment) 54

26 Effect of Different Levels of Compost and Gypsum on Chemical Propertiesof Saline Sodic Soil after Second wheat crop (Field Experiment)

55


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27 Effect of compost and other organic materials on yield and yieldparameters of first rice crop (2003) on normal soil (pot experiment)

56

28 Effect of compost and other organic materials on yield and yieldparameters of first wheat crop (2003-04) on normal soil (pot experiment)

57

29 Effect of compost and other organic materials on yield and yieldparameters of second rice crop (2004) on normal soil (pot experiment)

58

30 Effect of compost and other organic materials on yield and yieldparameters of second wheat crop (2004-05) on normal soil (pot experiment )

59

31 Effect of compost and other organic materials on chemical characteristicsof normal soil after first rice crop (pot experiment)

60

32 Effect of compost and other organic materials on chemical characteristics ofnormal soil after first wheat crop (pot experiment)

61

33 Effect of compost and other organic materials on chemical characteristics ofnormal soil after second rice crop (pot experiment)

62

34 Effect of compost and other organic materials on chemical characteristicsof normal soil after second wheat crop (pot experiment)

63

35 Effect of compost on rice nursery (2004) grown in the field fortransplantation

64

36 Effect of compost on rice nursery (2005) grown in the field fortransplantation

64

37 Effect of compost on nutrient concentration of rice nursery (2004) grownin the field for transplantation

65

38 Effect of compost on nutrient concentration of rice nursery (2005) grownin the field for transplantation 66

39 Economics parameters of experiment, Comparative efficiency of chemicalfertilizers and compost in normal soil

67

40 Economics parameters of experiment, Reclamation of salt affected soils 68


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SUMMARY

The soils of Pakistan are low in organic matter due to which over all fertility

status is not higher enough to give the good yield of different crops. Among the causes of

low organic matter are high temperature, low rainfall and removal of almost all the crop

residues except the roots. The mechanical harvesting and threshing of crops, especially rice

and wheat have aggravated the situation. Burning of rice and wheat straw has become a

popular practice among farmers. To ensure the good productivity of crops, the organic

matter contents have definitely to be raised. But after the introduction of chemical

fertilizers, the conventional sources of organic matter like farmyard manure (FYM) and the

green manure have almost been left gradually. Resultantly, the organic matter status of

Pakistan soils has already reached the bare minimum.

The present project was planned and approved by Pakistan Science Foundation

to standardize the composting technology and assess its usefulness in enhancing fertility

status and reclamation of salt-affected soils resulting in more crop yields. The project was

approved for 3 years with a total cost of Rs.3, 75,615/-. Soil Salinity Research Institute, Pindi

Bhattian and University of Kassel, Witzenhausen, Germany collaborated to accomplish this

work. Soil Salinity Research Institute implemented this project while the University was

playing only the guiding role, if and when needed.

Rice and wheat straw were composted successfully in constructed pits of 4x4x4 feet.

Chopped material was piled in 5 cm layers alternated with thin layer (2 cm) of farmyard

manure and incubated at moisture of 40-50 %. Well-rotten compost was, thus, prepared in

60-70 days. Five experiments on rice as well as wheat were conducted to assess the

usefulness of the produced compost. Three experiments were carried out in the field and

two in the Wire house. The themes of these experiments were to assess the level of compost

with or without chemical fertilizers, comparison of compost with FYM and Sesbania green

manure. The efficiency of compost in reclamation of salt-affected soils was also evaluated.

The salient results of different experiments are as under:


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2. Comparative efficiency of chemical fertilizers and compost innormal soil (Pot and field experiments)

Maximum plant height, number of fertile tillers, total biomass and grain

yield of paddy as well as wheat were significantly increased when chemicalfertilizer or compost was added in normal soil. Maximum paddy yield was

recorded with the addition of 20 t. ha -1 compost while the highest yield of wheat

was recorded with the combined application of compost (10 t. ha -1) and chemical

fertilizers at the half rates. Soil pH and SAR decreased significantly while EC e

was increased slightly. Addition of compost enhanced the organic matter

content, available phosphorus and potassium level of the soil.

3. Reclamation of salt affected soils

Compost proved greatly helpful in increasing the yield of rice and wheat

crops in saline sodic soils. Plant height, total biomass and grain yield of paddy as

well as wheat significantly enhanced when either compost or gypsum was

applied. A significant effect of compost alone or its combination with gypsum in

decreasing soil pH, EC e and SAR was recorded. Similarly, an increase in organicmatter, phosphorus and potassium was noticed in all the treatments when

compared with control. The reclamative effect of compost alone or in

combination with gypsum was found to be very clear. The salinity parameters

reduced significantly and brought within permissible limits.

4. Comparison of different sources of organic material

The yield components (maximum plant height and number of fertile

tillers), total biomass and yield of paddy during both the years were maximized

when compost was applied in combination with doze chemical fertilizers.

Other combinations (Sesbania green manure, FYM alone as well as combination

with fertilizer) remained significantly inferior. Soil pH and SAR were decreased


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significantly when different organic materials were applied alone or in

combination with chemical fertilizers. An increase in organic matter, available

phosphorus and water soluble potassium contents of the soil was noticed after

the harvest of four crops in all the treatments when compared with control.

5. Use of compost in rice nursery raising

Average height of rice nursery when measured at the age of transplanting

was affected positively with the use of compost and urea fertilizer. The fresh and

oven dry weight of rice nursery was also significantly greater in these treatments

when compared with control. Chemical analysis of plant samples revealed that

addition of compost enhanced the concentration of total phosphorus, total

potassium, calcium, magnesium, zinc and copper.

Conclusions:

It can be concluded that composting of crop residues in rice-wheat

cropping system is very useful practice, which can easily be adopted instead of

burning. This will not only ensure high yields but also improve the fertilitystatus of the soil on long term basis. Decreasing the use of chemical fertilizers to

half can also decrease the cost of crop production. The compost can also be

utilized for reclamation of salt-affected soils in combination with gypsum. These

practices are environmental friendly and will help to decrease the pollution.


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3. DETAILED REPORTi) Project Title Appropriate Composting technology for

rice wheat system in normal and salt-

affected soils.ii) Report Period Three years (June 1, 2003 to May 31, 2006)

iii) Introduction Pakistan spreads over an area of 79.61 million hectares (M ha), however, only

about one-fourth of this area supports the population of 145 million. The country is the

sixth biggest nation of the world in terms of population (ANONYMOUS, 2003).

According to projections at the present growth rate, population will be 201 million inthe year 2010 and the requirement of different commodities will be doubled. The annual

growth rate of 1.9 %, forces the over-exploitation of the natural resources of the country

(ANONYMOUS, 2005). Land is the major non-renewable resource and faces the biggest

threat of degradation. Land resources of the country are degrading at an alarming rate

and causing environmental problems. Almost 70 % of the total area of the country falls

under arid and semi-arid regions while in irrigated belt salinity is threatening about 5

M ha.Because of continued cultivation, the soils of Pakistan are becoming low and

deficient in organic matter contents. According to Nizami and Khan (1989) Pakistani

soils exhibit poor aggregate stability and are low in iron and aluminum contents. Out of

33, 7714 samples analyzed in the Punjab, 96% of the samples were in the poor to

medium range of organic matter and only 4% exhibited a moderate to adequate level.

Micronutrient deficiency such as zinc is widespread in all rainfed areas (Rafique et al.,

1990). Cultivation of high yielding crop varieties and multiple cropping is depleting the

fertility of soils at a rapid pace. The soils that were once well supplied with available

nutrients are now gradually becoming deficient (Zia et al. 1994). A decline of crop

yields under continuous cultivation is due to loss of soil organic matter including other

factors (Juo et al. 1995). Ponnamperuma (1984) reported an increase of 0.4 t ha -1paddy


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due to rice straw incorporation over burning or removal. This increase was per season

and enhanced with time as a result of fertility build up. To ensure the good productivity

of crops, the organic matter content has definitely to be increased.

Organic matter is regarded as a very important parameter of soil productivity. Ithas number of important roles to play in soils, both in their physical structure and as a

medium for biological activity. Organic matter makes its greatest contribution to soil

productivity. It provides nutrients to the soil, improves its water holding capacity, and

helps the soil to maintain good tilth and thereby better aeration for germinating seeds

and plant root development (Zia et al., 1993). Use of compost can be beneficial to

improve organic matter status. Compost is rich source of nutrients with high organic

matter content. Physical and chemical properties of soil can be improved by using

compost, which will ultimately increase crop yields. Depletion of nutrients and poor

organic matter contents of Pakistani soils can only be replenished by applying compost

to these soils. So use of compost is the need of the time (Sarwar, 2005).

Compost prepared from crop residues, leaves, grass chippings, plant stalks,

wines, weeds, twigs and branches are very good alternative which proved useful in

many countries of the world. Use of compost has not only been adopted to enhance soil

organic matter and enrich it in different nutrients but also to control the environmental

pollution from debris. In Pakistan, this field remained ignored and no systematic study

was conducted to standardize the composting technology. Raw manure use has often

been associated with imbalances in soil fertility (Kuepper, 2003) because it is often rich

in specific nutrients like phosphate or potash. In contrast an effective composting

process converts waste raw products into humus, which is relatively stable, and

chemically active organic fraction found in fertile soils. Good compost is a safe

fertilizer which is low in soluble salts and does not burn plants. Smiciklas et al. (2002)

reported significantly higher yield of corn due to application of mature compost as

compared to raw or same un-composted material.


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Soil salinity and sodicity are among the major constraints of present agriculture

in Pakistan. According to estimates 6.6 M ha are affected from salinity/sodicity to

various degrees in Pakistan (Khan, 1998). The area affected from slight to moderate

problem is 1.83 M ha (Anonymous, 2003) which can be rehabilitated by using compostand other organic materials. Moreno et al. (1996) amended a calcareous soil (pH 8.77)

with sewage-sludge compost. Hileman et al. (1980) noted a significant drop in Na level

of salt-affected soil after application of compost. Zaka et al. (2003) noticed a significant

decrease in EC e, pH and SAR of salt-affected soil (EC e =10.1813.1 dSm -1, pH = 9.54-9.92

and SAR = 72.2-78.3) due to application of organic amendments which was attributed to

the formation of organic acids and resultant mobilization of native Ca. Physical

properties of a saline-sodic soil like bulk density, porosity, void ratio, waterpermeability and hydraulic conductivity were significantly improved when FYM(10tha -

1) was applied in combination with chemical amendments (Hussain et. al. 2001). Thus,

application of organic materials including compost can prove very useful in

rehabilitation of salt-affected soils to the original potential along with significant

improvement in physical conditions.

According to the experiments of Sarwar (2005), the grain yield and yield

components (plant height, number of fertile tillers and 1000 grain weight) of rice andwheat increased significantly with the application of different organic materials but

compost proved the most superior in this regard. The combination of compost with

chemical fertilizer further enhanced the biomass and grain yield of both crops. The soil

pH s was lowered and SAR decreased due to acidic effect of compost and other organic

materials, formation of acids, release of Ca and leaching of Na. These effects were more

pronounced in saline sodic soils. There was a slight increase in EC e of normal soil.

However, EC e of saline sodic soil decreased due to the leaching of salts as a result of

improved soil physical conditions. The available amount of all the major plant nutrients

(N, P, K, Ca and Mg) and organic matter increased in the soil. Therefore, plant uptake of

these nutrients also increased when compost and other organic materials were applied.

The effect of combination of compost and chemical fertilizers was also positive. Thus,


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systematic investigations were required to formulate recommendations for the farmers

regarding composting of crop residues and application in their soils for the increased

and sustainable crop production through improved soil fertility and a decrease in soil

salinity/sodicity.Keeping in view the prevailing situation (nominal quantity of organic matter

status, low fertility and high salt content in the soils of Pakistan), it was direly needed

that the use of organic matter be enhanced. The best alternative is the compost prepared

from different waste materials, especially rice and wheat straw in the rice-wheat

cropping system. The project, Appropriate Composting Technology for rice-wheat system in

normal and salt-affected soils, was planned to standardize the composting technology and

assess its usefulness in enhancing fertility status and reclamation of salt-affected soilsresulting in more crop yields. The Pakistan Science Foundation approved this project

for 3 years. Soil Salinity Research Institute, Pindi Bhattian and University of. Kassel,

Witzenhausen, Germany collaborated to accomplish this work. Soil Salinity Research

Institute, Pindi Bhattian implemented the Project while the University performed the

guiding role only, if and when needed. The specific objectives of this project were as

under: -

To standardize composting technologies for different organic material and

kitchen waste.

To assess the effects of compost on crop yield enhancement and soil

fertility improvement.

To evaluate the probable impact of compost on reclamation of salt-affected soils.

To recommend an economical and practically adoptable technology fordissemination amongst farmers.


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EXPERIMENTAL PROCEDURES

A) Method for Compost production

The hot method of composting was used for production of compost. Inthis method constructed pits of 1.25x1.25x1.25 meter size (total volume 1.95 m 3) were

used to accelerate the decomposition process so as to kill most of the weed seeds and

pathogens. The residues of crops (rice and wheat) and wastes (tree leaves, flower, wines

and grasses) were chopped and piled in the pits. A layer of animal manure 3-5 cm thick

was spread on the top of the piled material in order to initiate and enhance the

decomposition process. The piled material was kept at different moisture levels (30, 40,

50, 60 & 70 %). The materials were turned weekly. Urea and sugar solutions weresprayed twice. Microbial inoculation (Effective microbes = EM) was also tested. About

one ton compost was, thus, prepared before the start of two seasons (Rabi and Kharif).

B. Use of Compost

The use of compost for nutrient supplementation in rice-wheat cropping

system as well as reclamation of salt-affected soils was investigated after compost

preparation. The treatment details of these studies are as under: -

i). Comparative efficiency of chemical fertilizers and compost

T1 Control

T2 Recommended dose of NPK fertilizer

(Rice N-P-K = 100-70-70 Kg.ha -1)

(Wheat N-P-K = 140-110-70 Kg.ha -1)

T3 Compost @ 20 t ha -1

T4 Half recommended dose of fertilizer + compost @ 10 t ha -1

T5 Compost @ 10 t ha -1 + straight fertilizers so as to make total

N, P & K equal to recommended dose (T2)


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This experiment was conducted in wire house as well as field in a permanent layout for

two years on rice-wheat cropping system. Yield of crops were recorded at maturity and

soil was analyzed for EC e, pH s and SAR.

ii). Comparison of different sources of organic material

T1 Control

T2 Sesbania green manure @ 1.0% of soil weight ( 150 g.pot -1)

T3 FYM @ 1.0% soil weight ( 150 g.pot -1)

T4 Compost @ 1.0% of soil weight ( 150 g.pot -1)

T5 Half recommended dose of N, P & K + Sesbania green

manure @ 0.5% of soil weight (7 5 g.pot -1)

T6 Half recommended dose of N, P & K + FYM @ 0.5 of soil

weight (7 5 g.pot -1)

T7 Half recommended dose of N, P & K + compost @ 0.5 of soil

weight (7 5 g.pot -1)

T8 Recommended dose of N, P & K fertilizerT9 Half recommended dose of N, P & K fertilizer

The layout design of this pot experiment was completely randomized with

three replications. Rice and Wheat crops data were recorded at maturity and soil was

analyzed for EC e, pH s, and SAR continuously for two years.

iii) Reclamation of salt affected soils

T1 Control

T2 Gypsum @ 100% of soil gypsum requirement (3.50 t.ha -1)

T3 Compost @ 24 t.ha -1


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T4 Compost @ 24 t.ha -1 + Gypsum @ 100% G.R




Compost and gypsum were applied to a salt-affected soil (Table 2). Tube- well water

was applied (3 irrigations) for leaching of salts. Rice and wheat crops were grown in

sequence for two years. Crop data were recorded at maturity and soil was analyzed

after harvesting of crop. The recorded data were put to statistical analysis.

iv) Use of compost in rice nursery raising

In order to obtain healthy rice nursery with ample nutrient uptake, the

following experiment was conducted in RBC design with 3 replications for consecutive

two years.

T1 Conventional method: Covering the spreaded seed with silt or soil

T2 Covering the spreaded seed with compost @ 1000 kg ha -1

T3 Covering the spreaded seed with well rotten farm yard manure @1000 kg ha -1

T4 Covering the spreaded seed with soil but application of nitrogen@ 50 kg ha -1 after10-15 days

The uniform quantity of seed was spreaded per sq. feet. Average height,

fresh and oven dry weight of rice nursery was recorded. The samples of rice nursery

harvested at the age of 35-40 days were analyzed for N, P, K, Ca, Mg, Zn and Cu

concentrations.


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V) RESULTSA) Composting technology

It was observed that:

Excessive moisture (> 60%) or dryness (moisture less than 40%) delayed theprocess of compost production by 10-15 days. The maintenance of 40-60%moisture completed the process within 60-70 days.

The application of urea @ 1% enhanced the process by 7-10 days

The application of microbial inoculum (EM) fastened the process by 10-15days. One liter of EM (obtained from University of Agriculture, Faisalabad)was applied after its 10 times dilution.

The analysis of compost and its comparison with farmyard manure as well as Sesbania

green manure indicated that EC & pH of compost was more than Sesbania but lesser

than FYM (Table 1). Organic carbon and total N was maximum in compost. However,

potash was the minimum in this organic product.

B) Use of compost

1) Nutrient supplementation i) Comparative efficiency of compost and fertilizer

This experiment was conducted for two years in pot as well as field and

results of both these experiments indicated the same trend of improvement in yield and

its components as well as soil parameters. The data indicated that maximum plant

height, number of fertile tillers, total biomass and grain yield of paddy as well as wheat

were significantly increased when chemical fertilizer or compost was added in normal

soil (Table 3, 4, 5 & 6). Maximum yield of paddy was recorded with the addition of 20 t.

ha -1 compost while the highest yield of wheat was recorded with the combined

application of compost (10 t. ha -1) and chemical fertilizers at the half rates (T4). The

application of fertilizer alone proved inferior treatment. The results of pot experiment

were some what different from the field conditions (Table 11, 12, 13 & 14). The paddy


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and wheat grain yield was found to be significantly more in treatments of compost

alone (T3) or its combination with fertilizer at half rate (T4). However, control remained

at the bottom in field as well as pot experiment in respect of paddy and wheat grain

yield.The analysis data of field (Table 7, 8, 9 & 10) and pot (Table 15, 16, 17 & 18)

experiments indicated that soil pH and SAR decreased significantly while EC e was

increased slightly. The differences among various treatments were significant when

examined statistically. However, the use of chemical fertilizer alone (T2) remained at

par with control for pH and EC e of the soil. The application of compost alone @ 20 t. ha -1

(T3) lowered the soil pH to the maximum level in contrast to the electrical conductivity

of the soil that approached the highest value in this treatment. Use of chemical fertilizeralone (T2) remained inferior to compost in this regard. Addition of compost to the soil

enhanced the organic matter content, available phosphorus and potassium level in the

soil. The above findings were almost similar in soil samples collected after the harvest

of rice as well as wheat both in pot and field experiments.

ii) Reclamation of salt-affected soils

Data (Table 19, 20, 21 & 22) indicated that compost proved greatly helpful in

increasing the yield of rice and wheat crops even in salt-affected soils. Plant height, total

biomass and grain yield of paddy as well as wheat significantly enhanced when either

compost (T3) or gypsum (T2) was applied. Both of these treatments were superior to

control. Combined application of gypsum and compost (T4 & T5) was assessed as the

best treatments for paddy yield whereas maximum wheat grain yield of second crop

was recorded with the application of gypsum @ 50 % G.R. along with compost @ 24 t.

ha -1 (T6). Decreasing the addition (T6 & T7) of gypsum or compost to the half level also

decreased the efficiency of these treatments.

A significant effect of compost alone or its combination with gypsum in

decreasing soil pH, EC e and SAR was recorded (Table 23, 24, 25 & 26). Similarly, an

increase in organic matter, phosphorus and potassium was noticed in all the treatments


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when compared with control. The best treatment was combination of gypsum @ 100 GR

and compost @ 24 t.ha -1 (T4). After the harvest of rice crop, the salinity parameters were

brought almost within the permissible limits. Further soil improvement was observed

after the first wheat crop. The pH values became statistically similar in all thetreatments except control after rice harvesting but differences still existed in respect of

soil SAR. Although, the differences for soil EC among treatments were significant when

compared with control but the last four treatments (T4 to T7) were noticed as non-

significant among themselves after the harvest of rice. The combination of gypsum and

compost both at the higher level (T4) remained as the best treatment even at the end of

second year of experimentation (after both rice as well as wheat crops). The differences

among various treatments for organic matter, phosphorus and potassium also remainedsignificant in soil samples analyzed after four crops.

iii) Comparison of different sources of organic material

The yield components (maximum plant height and number of fertile tillers),

total biomass and yield of paddy for the both years were found to be maximum when

compost was applied in combination with doze chemical fertilizers (Table 27 & 29).

Other combinations (Sesbania green manure as well as fertilizer alone remained

significantly inferior. Compost alone proved superior to Sesbania green manure and

FYM. Control produced the minimum biomass and paddy yield. In case of subsequent

wheat, compost alone as well as its combination with chemical fertilizer at the

recommended rate was observed as the best treatments (Table 28 & 30). The combined

effect of Sesbania and fertilizer was also found to be superior to rest of the treatments.

The usefulness of FYM was less than other organic materials.

Like the previous experiments, soil pH and SAR were decreased significantly

when different organic material were applied alone or in combination with chemical

fertilizers (Table 31, 32, 33 & 34) when these parameters were evaluated after rice and

wheat harvesting . The highest decrease was recorded in case of compost as compared


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to other organic sources. Chemical fertilizers at recommended or half recommended

levels were assessed as the inferior treatments. However, both of these treatments were

still better than control in respect of soil chemical characteristics of soil. There was slight

increase in EC of the soil with the application of organic amendments. An increase inorganic matter, available phosphorus and water soluble potassium contents of the soil

was noticed after the harvest of four crops in all the treatments when compared with

control. The differences among various treatments remained significant statistically.

iv) Use of compost in rice nursery raising

It was noted from the data (Table 35 & 36) that average height of rice nursery

when measured at the age of transplanting was affected significantly with the use of

compost and urea fertilizer. The fresh and oven dry weight of rice nursery was also

significantly greater in these treatments when compared with control. The treatment of

FYM proved inferior to compost and urea but remained superior to control. Chemical

analysis of plant samples of rice nursery revealed that although highest concentration of

total nitrogen was observed in T4 receiving urea fertilizer but treatment of compost (T2)

followed it (Table 37 & 38). The concentration of total phosphorus, total potassium,

calcium, magnesium, zinc and copper was found maximum in T2, followed by T4. The

differences among various treatments when compared with control remained

significant statistically.

VI Discussion

The project data collected during pot and field experimentation clearly indicated

that composting of crop residues along with other farm wastes is not only possible butits subsequent application also significantly improved the yields of rice and wheat in

normal as well as salt-affected soils. The compost proved superior to Sesbania green

manure and farmyard manure in terms of crop yields as well as soil improvement. The


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increase in crop yields occurred mainly due to decrease in soil pH and SAR coupled

with improvement in nutrient supplying capacity of soil.

Soil pH:Soil pH is the single soil characteristic which elucidates an overall picture of the

medium for plant growth including nutrient supply trend, fate of added nutrients,

salinity/sodicity status and soil aeration, soil mineralogy and ultimate weather

conditions of the region. The pH is alkaline in many areas of Pakistan that are included

in arid and semi-arid zones. The numerical values are always more than 8.00 even in

normal soil while pH of sodic soils may approach 10.00. Hence, a decrease in soil pH

due to any land management strategy is always appreciable and result in ultimate

conversion of soil medium towards favourable one and net translation into increased

yields. Application of compost in particular and other organic materials (FYM and

Sesbania green manure) in general reduced the soil pH significantly in pot and field

experiments conducted on normal and saline sodic soils.

The production of organic acids (amino acid, glycine, cystein and humic acid)

during mineralization (amminization, ammonification and nitrification) of organic

materials by heterotrophs and autotrophs would have caused a decrease in soil pH. The

pH of an acidic soil is controlled by H, Fe and Al ions while that of alkaline soils is

driven by Ca and Mg (Brady, 1990) and Na is in controlling position when the soil is

sodic as well. The possible reactions resulting a net decrease in pH of the soils can be

visualized as under:

-- Ca2+

-- Ca2+ -- H+ -- - -- Ca2+ + 2H -- Mg2+ + 2Ca (1)

-- Mg2+ -----H+

(Normal alkaline soil)

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The released Ca will increase the Ca concentration of the soil solution resulting in

decrease of soil SAR. It may also precipitate as CaCO 3 in calcareous soils.

--H+ -- Na + ---H+ -- Na + + 2H --- + 2Na (2) -- Na + ----Na + -- Ca2+ --Ca2+

(Sodic or Saline-Sodic Soil)

The Na ion such released may be leached down into the deep profile because all the

sodium salts (Even Na 2CO3) are highly soluble.

Electrical conductivity of soil:

Electrical conductivity (EC) is a soil parameter that indicates indirectly the total

concentration of soluble salts and is a direct measurement of salinity. Salinity is a

problem of arid and semi-arid regions in the world. This is particular problem ofirrigated agriculture in such areas. The critical limit of this soil character is 4.0 dS.m -1

above which plants face constraints of water uptake due to physiological unavailability,

osmotic effects due to decrease of water potential and restricted nutrient uptake that

may be due to specific ion effect. The results of present research investigations

regarding EC e indicated two different trends in normal and salt-affected soils. A trend

of general increase in EC of normal soil was observed in pot as well as field experiments

after rice and wheat crops. Application of organic materials particularly caused anincrease of this soil parameter. The decomposition of organic materials releases acids or

acid forming compounds which react with the sparingly soluble salts already present in

the soil and either convert them into soluble salts or at least increase their solubility.

Hence, the EC of soil was increased. e.g., CaCO 3 ever present in the soils of arid and

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semi-arid regions may be converted to CaHCO 3 or ever to Na 2CO3 which are more

soluble forms. However, the quantum of increase will depend how much quantity of

the acids or acid forming substances was produced which will in turn rely upon the

amount of the organic materials applied. The other factors to be taken intoconsideration are the removal of soluble salts from the soil eco-system. If the physical

properties, especially hydraulic conductivity, of the soil are good and the system is

open as in case of field experiments, the effect of increase in soil EC will partially be

mitigated.

However, when the experimental soil was saline sodic, the effect of different

treatments on soil EC totally changed. A net decrease in EC of the field soil was

observed. The EC of such soils was already beyond the critical limit of 4.0 dS.m -1. Themain reason for this decrease in soil EC which can be suggested with logic is the

leaching of soluble salts into the lower profile. There are clear reports in the literature

(Tandon, 2000) that physical properties (hydraulic conductivity, bulk density and total

porosity) of salt-affected soils greatly improved when organic materials in the shape of

manure or compost are applied. Physical properties of soil like bulk density, porosity,

void ratio, water permeability and hydraulic conductivity were significantly improved

when FYM (10 t ha -1) was applied in combination with chemical amendments resultingin enhanced rice and wheat yields in sodic soil (Hussain et al., 2001). Other organic

materials like rice straw, wheat straw, rice husk and chopped salt grass also improved

these physical properties of a saline sodic soil (Hussain et. al., 1998). Soil organic matter

encourages granulation, increases cation exchange capacity (CEC) and is responsible for

up to 90 % adsorbing power of the soils.

Sodium adsorption ratio (SAR) of soil:

Sodium adsorption ratio (SAR) is yard stick used to measure the sodicity of a

soil. Sodicity is the accumulation of sodium ion in excessive quantities which hinder

plant growth directly or through the impairment of physical soil conditions. A clear

decrease in SAR of the normal as well as salt-affected soil was recorded in different pot


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and field experiments after wheat as well as rice crops. Studies of Sarwar (2005) and

Zaka et al. (2003) also indicated the same trend of decrease in soil SAR with the use of

FYM, rice straw and Sesbania green manure. They attributed this reduction in SAR of

the soil with organic materials due to the release of organic acids causing mobilizationof native calcium present as CaCO 3 in the soil.

The values of SAR become shorter either due to an increase in divalent cations

(Ca + Mg) or decrease in monovalent cation (Na). The measured values of cations

indicated that Na decreased while Ca + Mg increased after the application of different

organic materials. The chemical reactions proposed under discussion on soil pH further

elaborates how a net increase in Ca + Mg and decrease in Na in the soil solution

occurred (Equation 1 & 2). The acid or acid forming substances expelled Na or Ca + Mgfrom the clay micelle, the hydrogen ion taking their place. Sodium salts being readily

water soluble left the soil system and went into the lower depths of soil profile. The

divalent cations (Ca + Mg) increased the net concentration of the soil solution.

However, a part of these would have also precipitated with carbonates (CO 3) and

bicarbonates (HCO 3) present in the soil.

Soil Organic Matter:

Organic matter is regarded as the ultimate source of nutrients and microbial

activity in the soil. It is the deciding factor in soil structure, water holding capacity,

infiltration rate, aeration and porosity of the soil. Thus, if only one soil parameter of

productivity is to be considered that may be organic matter. During these studies,

different sources of organic matter at variable rates were tried for their efficiency. It was

observed that every rate of all organic materials resulted in an increase of soil organicmatter status in the pot as well as field experiments of normal and salt-affected soils.

Compost proved superior to FYM and Sesbania green manure. A combination of

compost and chemical fertilizer proved further helpful in increasing the organic matter

level of the soil. Similar results are also obtained by earlier workers (Sarwar, 2005;


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Smiciklas et al. 2002; Kumazawa, 1984; Sarwar et al. 2003; Ahmad et al. 1996; Parr and

Hornick, 1994; Hileman, 1980; Pattanayak et al. 2001; Singh et al. 2001; and Selvakumari

et al. 2000).

The reason for the increase in organic matter status in all treatments of field andpot experiments is very clear. Application of organic matter resulted in overall increase

of the soil organic matter level. The status of organic matter in the soil had a

relationship with the quantity applied. Comparatively more biomass production in

different treatments also contributed more crop residues to the soil that caused an

improvement of organic matter status of the soil.

Available Phosphorus: Phosphorus is second major element for plant growth. It is an integral part of

adenosine diphosphate (ADP) and adenosine triphosphate (ATP); the two compounds

involved in almost all energy transformations in plants. It is also essential part of DNA,

which is the seat of genetic inheritance in plants. Perhaps the availability of this nutrient

is the most dynamic in the soil. Beside other factors, its availability is controlled by soil

pH, clay content, calcareousness and organic matter percentage of the soil. The ideal pH

for maximum availability of phosphorus ranges from 6.5 to 7.5. BRADY (1990)

represented variable soil pH effects on availability of phosphorus by the following

equation:

H 2PO4- H2O + HPO 42- H2O + PO 43- (3)

H+ H+

(Very acid solutions) (Very alkaline solutions)

All the experimental soils were alkaline having pH more than 8.0. As described earlier,

there was a significant decrease in soil pH of all experimental soils. Hence, an increase

in availability of phosphorus was especially observed. An increase in organic matter

content of the soil further favoured availability of soil phosphorus. The overall

conclusions drawn from these data are that organic materials contributed more than


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chemical fertilizer in building up the phosphorus status of the soil. The compost proved

superior to FYM and Sesbania green manure. When chemical fertilizer containing

soluble Ca (H 2PO4) 2.H2O is added to the soil, even those of relatively high pH, the Ca

(H2PO4) 2.H2O in fertilizer granules attracts water from the soil resulting in thefollowing reaction:

Ca (H 2PO4) 2.H2O + H 2O CaHPO 4.H2O + H 3PO4 (4)

But the availability of phosphorus is also affected by the presence of CaCO 3 in the

calcareous soils. The process indicated in the above equation is reverted and fixation

process starts. Then the equation, which demonstrates the reaction, will be as under:

Ca (H 2PO4) 2.H2O + 2 CaCO 3 Ca3 (PO4) 2 + 2CO 2 + 2H 2O (5)

This equation indicates the process in operation at pH 8.0 or above. Thus, the available

phosphorus starts becoming unavailable. When an organic source of nutrition is

applied, the bond of phosphorus compounds with CaCO 3 is broken and the operation

of above equation is either delayed or terminated. Resultantly, phosphorus is kept at

higher amounts in the available form.

Earlier scientists also investigated the availability of phosphorus in the soil by

using various organic materials and their findings supported the above results.

According to Parma and Sharma (2002) and Hileman et al. (1980) the available

phosphorus status of the soil improved with the use of organic materials in the form of

compost and FYM. Pattanayak et al. (2001) noted that the available level of phosphorus

in the soil increased with the use of green manures. Similarly, Selvakumari et al. (2000)

and Sarwar (2005) observed significant increase in available P content in the soil with

the use of organic and inorganic manures over control. The same trend of improvement

in availability of phosphorus in the soil was recorded by Verma et al. (2002), Singh et al.

(2002) and Swarup and Yaduvanshi (2000).


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Water Soluble Potassium:

Potassium plays many essential roles in plants. It is an activator of many

enzymes responsible for plant processes; energy metabolism, starch synthesis, nitrate

reduction and sugar degradation. It helps in regulating the opening and closing ofstomata of leaves. In the present studies, water soluble potassium (as assessed after the

harvest of rice and wheat crops) increased when compost was applied in combination

with chemical fertilizer. This trend was noticeable in normal as well as salt-affected

soils.

Potash is found in different forms; readily available/water soluble, exchangeable

and fixed as part of clay micelle. All the forms are in a balance with each other. A shift

in one form triggers similar changes in other forms automatically. When the acid oracids forming compounds are added in the form of organic materials to the soil, these

also affect potassium availability. The effect is positive resulting in more availability of

K to the plants. The hydrogen ion released from organic materials exchange with K

from exchange site or set free from the fixed site of the clay micelle. Thus, the overall

status of soil regarding availability of potassium content is improved. The increase

observed in different treatments of both studies is thus explainable with this hypothesis.

The probable equation proposed for K release will be as under:

-- K+ --Ca2+ -- K+ + 2H --H + +2K (6)

-- Mg2+ --H+ -- Ca2+ -- Mg2+

Research conducted by other scientists proved the above hypothesis. Sarwar (2005),

Selvakumari et al. (2000), Swarup and Yaduvanshi (2000), Singh et al. (2001),

Khoshgoftarmanesh and Kalbasi (2002), Verma et al. (2002) and Singh et al. (2002) also

reported that continuous use of chemical fertilizers, FYM, compost and green manure

enhanced the potassium status in the soil.

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CHEMICAL COMPOSITION of PLANTS:

The chemical composition of plants is a translation of the conditions under which

they complete their life cycle fully or a part of it. The chemical composition is a net

summary of all the changes either positive or negative, which were faced by the plants.The nutrient uptake is directly or indirectly affected by many factors like total

concentration as well as available quantity of different nutrients, root development,

aeration, water potential, climatic conditions and other related soil parameters. Beside

all these, the presence of a nutrient in available form for the plant has to play the

deciding role. The fertility status of Pakistani soils is very low. Application of nutrients

in readily available form rapidly enhances the availability of that nutrient in the soil but

all is neither taken up by plants nor remain permanently in available form. Thedynamic processes are continuously in operation in the soil or accelerated and a major

part of the applied nutrients is rapidly converted into unavailable forms. Some fraction

of it may be permanently fixed but when organic materials are applied, the overall

fertility status of the soil is built up, the total reserve of nutrients is increased and a

stage for enhanced availability is set up.

The present studies were investigated to evaluate the possibilities of replenishing

the nutrient pool in the soil. It was observed that major nutrients uptake by rice

nursery was significantly increased when organic matter in different forms (compost

and FYM) was applied to the soil. The concentration of N, P, K, Ca, Mg, Cu and Zn in

rice nursery improved appreciably. Compost proved superior to FYM and chemical

fertilizer. The application of chemical fertilizer in the form of urea was better than

compost only for the nitrogen but remained inferior for all other nutrients. It has been

observed in earlier section on soil parameters that organic matter, nitrogen,

phosphorus and potassium contents of soil significantly enhanced due to different

treatments of experiments, especially, when organic matter was added alone or along

with chemical fertilizer. This increased availability of N, P and K, that resulted in more

uptakes of these nutrients by the plants. The pH of the soil also indicated a positive

change i.e. a shift towards neutrality. This positive change enhanced the solubility of


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different nutrients especially phosphorus in the soil. The form of phosphorus ion may

have converted from PO 43- to HPO 42- or even H 2PO - for short periods, which resulted

in increased concentration of phosphorus in the plants. Similarly, production of

hydrogen ions during decomposition of organic materials would have helped therelease of K from exchange site or from the fixed pool. The solubility of many nutrient

salts increases in the acidic medium like compost, which may have resulted in more

availability of nutrients for the plants. The good physical conditions of the soil resulted

from improved relative properties like water holding capacity, infiltration rate,

porosity, hydraulic conductivity, bulk density and ability against sudden temperature

changes favoured root growth. The more root volume enhanced nutrient uptake. The

presence of K in appropriate quantities catalyzed the metabolism processes (activatorof dozens of enzymes responsible for plant processes; energy metabolism, starch

synthesis, nitrate reduction and sugar degradation). It helps in regulating the opening

and closing of stomata of leaves and resulted in higher concentration of other

nutrients.

The application of organic materials changed the status of secondary elements in

the soil. The water soluble forms of Ca + Mg in soil significantly increased which

resulted in higher uptake of these two nutrients by the plants. There is always a directrelationship between the soil concentration of nutrients and its quantity taken by the

plants. The reasons for more availability of Ca + Mg have already been discussed in

soil section. These exchange reactions enhanced due to the release of hydrogen ion

from the decomposition of organic materials that resulted in more availability of Ca &

Mg for plants.

The observations of Mahmood et al. (1983) supported some of the above

presented logics. They argued that the phenolic compounds particularly the humic

compounds of compost enhanced the uptake of nutrients due to higher nutrient

content of the substrates like compost. The solubilization of soil K in the presence of

humus matter of compost was regarded as another cause of more nutrient uptake.

Kumazawa (1984) reported that immobilization and mineralization of N in the soil


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could be regulated by the addition of organic matter to improve N uptake by rice.

Similarly, Kumaraswamy (2000) claimed higher uptake of nutrients by plants. Tomar

et al. (1984) observed that increased solubility of rock phosphate in calcareous soil due

to the application of cattle dung. Tiwari et al. (2000) noticed faster rate ofmineralization and greater utilization of nutrients through the use of green manure in

combination with chemical fertilizer. Other scientists (Sarwar et al. 2003, Dixit and

Gupta 2000, Selvakumari et al. 2000 and Sarwar 2005) also observed increased uptake

of N, P and K by various plants when inorganic and organic sources of nutrients in the

form of chemical fertilizer, FYM, green manure and compost were applied to the soil.

Similarly, the findings of Singh et al. 2002, Pattanayak et al. 2001, Tabassam et al. 2002

and Yaduvanshi, 2001 were again in the same direction of enhanced N, P and Knutrients uptake by plants. Pattanayak et al. (2001) reported that N, P, K, Ca and Mg

uptake was the highest in the treatments receiving green manuring of

dhancha(Sesbania) with SSP + URP source of phosphorus and the lowest in no green

manuring treatment with URP source.

Crop yields:

Result of application of various inorganic and organic amendments, activities of

different natural processes taking place in the soil, efficiency of various physical and

manual operations as well as physical, chemical and biological changes appear in the

form of yield of crops. Thus, yield is the ultimate task of farming for increase in income.

The yield and different yield parameters of rice and wheat crops increased significantly

with the use of chemical fertilizer alone or in combination with various organic

materials applied in the form of Sesbania green manure, FYM and compost in all field

and pot experiments. Different yield parameters including maximum plant height,

number of fertile tillers plant -1 and total biomass were affected positively in these

treatments. The improvement in these parameters of yield contributed towards increase

in yield of rice and wheat crops. The use of compost proved superior to FYM and

Sesbania green manure when applied alone or in combination with chemical fertilizer.


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The improvement in grain yields of rice as well as wheat crops followed a sequence of

processes. Addition of different organic materials like Sesbania green manure, FYM and

compost enhanced the organic matter percentage of the soil that has been regarded a

key factor determining soil fertility and productivity. This increase in organic mattercontent in the soil improved the physical properties (bulk density, hydraulic

conductivity, water permeability, total porosity, void ratio and infiltration rate etc.) of

the soil. The betterment in physical properties of soil reduced the soil pH as various

acids or acid forming compounds were released from the addition of organic materials.

This reduction in soil pH increased the availability of soil nutrients for the plants and

resultantly more uptake of various nutrients by the plants was noticed. The enhanced

uptake of K by rice and wheat improved the metabolic activities in the plants. As aresult of all above processes, various yield components (maximum plant height and

number of fertile tillers plant -1) of rice as well as wheat crops were positively affected

and ultimately these components contributed towards increase in grain yields of these

crops.

In case of salt-affected soils, the reclamation of these soils occurred and as a

result of reclamation process, Na + salt present on the exchange site leached down and

H+ occupied its place lowering soil pH. Hence, better physical conditions for plantgrowth were created. Moreover, application of different organic materials improved the

physical properties of these soils permitting more leaching of excessive salts.

Findings of other scientists also favoured these hypotheses. Sarwar (2005) observed that

grain yield and yield components (plant height, number of fertile tillers and 1000 grain

weight) of rice and wheat increased significantly with the application of different

organic materials but compost proved the most superior in this regard. The

combination of compost with chemical fertilizer further enhanced the biomass and

grain yield of both crops. Zaka et al. (2003) observed significant increase in rice and

wheat yields with the use of FYM, rice straw and Sesbania. Singh et al. (2001) noted an

increase in grain yield of rice with the use of FYM and green manure in combination

with mineral fertilizer. They also observed the significant residual effect of FYM and


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green manure on the grain yield of wheat. Tiwari et al. (2001) claimed that to achieve

the highest grain production of rice under saline sodic soil conditions, the use of FYM

will be more profitable probably by increasing the cynobacterial N fixation. They also

noted the carry over effect of FYM applied to the rice crop on the grain production ofsucceeding wheat crop.

Economic Feasibility:

Economic feasibility is the final yard stick of an evolved technology if it is to be

recommended to the farmers for adoptation. Technically good techniques are found

sometimes economically unfeasible that becomes a major constraint for its

popularization. Hence, economics of field experiments was also calculated. Data

indicated that 42.7% more net income was realized when compost alone was applied in

the rice-wheat cropping system (Table 39). The increase in net income over control was

9.3% for chemical fertilizer application at the recommended doses. The combination of

fertilizer and compost at half levels economically proved a little bit inferior to compost

alone with a net increase of 41.7 % over control. The benefit cost ratio (BCR) was

computed as 0.36, 3.54, and 2.19 for fertilizer, compost and combination. Application of

compost at half level + NPK to bring the nutrients equal to recommended dose of

fertilizer revealed maximum BCR but decreased the net income that remained 28.9 %.

In reclamation experiment the conventional application of gypsum indicated maximum

BCR of 23.2 followed by combination of gypsum (100 % requirement) and compost (12 t

ha -1). However, maximum net income was obtained with full doses of gypsum and

compost where increase over control was 138.01 % (Table 40). The most feasible

treatment adjudged through combined parameters of increase in net income and CBR

was combined application of gypsum (100% requirement) and compost (12 t ha -1).


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vii) Conclusions

The following conclusions can be drawn from the results obtained from differentexperimentations.

1. Chopped crop residues of rice wheat cropping system can be compostedeasily by piling in cemented pits of 4 x 4 x 4 feet with layers of animal manureand incubating the material at 40-60 % moisture. Excessive dryness ormoisture delayed/stopped the process of decomposition.

2. Combined application of compost (10 t.ha -1) and chemical fertilizer at the halfrecommended level proved as the best strategy to obtain maximum yield ofrice and wheat crops. Thus, farmers can save half of the expenditure incurredon application of chemical fertilizer.

3. Combined addition of gypsum and compost increased the yield of crops evenin salt-affected soils. However, compost alone could also suffice.

4. An enhancement in fertility status of normal and salt affected soils and adecrease in salinity/sodicity parameters are possible due to application ofcompost. Compost clearly decreased soil pH and SAR.

5. An improvement in rice nursery was observed when compost (1000 Kg.ha -1)was applied instead of covering the seeds with soil or Farm Yard Manure(conventional method).Urea application, coupled with conventional method,

also proved useful.

Evolution of Technologies

Three technologies were evolved through research studies of this project.

1. Technology for composting of crop and plant residues at small scale levelunder prevailing conditions of rice zone.

2. Technology for partial substitution of chemical fertilizers through compost inrice-wheat system for sustained crop production in normal soil. The

technology envisages application of fertilizers at half level with combinationof compost prepared from crop residues available at farm. The technologywill help in reduction of cost of production and solving pollution problemoccurring through burning of rice and wheat straw after harvesting of cropswith combine harvester.


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3. Alternate Technology for reclamation of saline sodic soils through whichapplication of gypsum can be substituted partially or fully through compostprepared from crop residues from normal soil. This technology can help thefarmers for reclamation of salt-affected soils with the material available atfarm and they have neither to spend money on conventional amendmentsnor to transport it to the farm gate.

These technologies will be got registered as patents with the concerned organization.In this regard help of PSF will be sought.

Recommendations for the farmers

1. The residues of rice-wheat cropping system should not be burnt in the fieldsafter harvesting but be composted through chopping, piling in pits andincubation.

2. The prepared compost should be used for substitution of fertilizer to the halflevel for crop production in normal soil. This will help in cutting cost ofinputs to almost half.

3. The combined application of gypsum and compost both at half levels canhelp in reclamation and restoration of fertility saline sodic soils.

Recommendations for future research

Following are the fields in which further research is required:

1. Usefulness and probabilities of using compost in other cropping systems likewheat- summer fodder, cotton-wheat and sugarcane etc.

2. Benefits of compost when applied in lesser quantities.

3. Uses of composts for high valued crops like vegetables, fruit and nurseryplants.

4. Evolution of technology for large scale production of compost at farm level.

5. Development of mechanical devices for large scale production of compost atfarm level.


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B) Publications

The results of the experiments conducted under this project are very much

encouraging and are of farmers interest. These are under process for

publication in different journals of international repute.

C) Ph.D. degrees

Dr. Ghulam Sarwar (Co-P.I./P.I.) conducted major part of his Ph.D. research

at Soil Salinity Research Institute, Pindi Bhattian , as part of this project,

under supervision of Dr. Nazir Hussain (Ex. P.I.) and Professor Dr.

Schmeisky. He defended his thesis at University of Kassel, Germany and was

awarded Ph.D. Degree by that university. Copy of his dissertation is being

submitted separately.

D) List of Scientists

1) Dr. Nazir Hussain , Agricultural Chemist / Ex. Principal Investigator(From 01-06-2003 to 20-03-2005) of the Project, Soil Salinity Research Institute,Pindi Bhattian.

2) Dr. Ghulam Sarwar , Research Officer / Ex. P.I. (From 21-03-2005 to 31-08-2005) of the Project, Soil Salinity Research Institute, Pindi Bhattian.

3) Mr. Abdul Rasul Naseem , Assistant Agri. Chemist / P.I. of the Project(From 01-09-2005 to 31-05-2006) , Soil Salinity Research Institute, Pindi Bhattian.

4) Professor Dr. H. Schmeisky , Chairman, Department of LandscapeEcology and Nature Conservation, University Of Kassel, Germany (Ph.D.Supervisor).

5) Mr. Nisar Mahmood-ul-Hassan , Director, Soil Salinity Research Institute,Pindi Bhattian.

6) Mr. Amar Iqbal Saqab , Assistant Research Officer, Soil Salinity ResearchInstitute, Pindi Bhattian.


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Dr. Nazir HussainAgri. Chemist/ Principal Investigator

Mr. Abdul Rasul NaseemAssistant Agri. Chemist / Co-PI

Mr. Khalid MahmoodAssistant Agri. Chemist

Dr. Ghulam Sarwar Research Officer / Co-PI

Mr. Muhammad AnwarAssistant Agri. Chemist


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E) BIBLIOGRAPHY

Anonymous, 2003. Agricultural Statistics of Pakistan,2002-2003.Government of Pakistan, Ministry of Food, Agriculture & Livestock

(Economic Wing), Islamabad.Anonymous, 2005. Statistical Pocket Book. Federal Bureau of

Statistics. Government of Pakistan, Ministry of Food, Agriculture &Livestock (Economic Wing), 5-SLIC Building, F-6/4, Blue Area, Islamabad,Pakistan

Brady, N.C.2005. Nature and properties of soil (13th Edition).Macmillan Publishing Co. New York.

Hileman, L.H., G.Crossland and E. Burr. 1980. Performance ofcompost in reclaiming salt-damaged soils. Mimeograph Series. 279. pp. 1-9. Agri. Ata. Exp. Division of Agri., Univ. of Arkansas, Fayetteville.

Hussain, N., G. Hassan, A. Ghafoor and G. Sarwar. 1988.Biomelioration of sandy clay loam saline sodic soil. Proc. Sixth Int. MicroIrrigation Cong. March 8-10, 1998, Florida, USA. PP. 293-300.

Hussain, N., G.Hassan, M.Arshadullah and F.Mujeeb 2001.

Evaluation of amendments for the improvement of physical properties ofsodic soil. Int. J. Agric. Biology. 3:219-322.

Juo, A.S.R., A.Dabiri and K.Fram zluebbers 1995. Acidification of akaolinitic Alfisol under continuous cropping and nitrogen fertilization inWest Africa. Plant and Soil. 171: 245-253.

Kuepper, G. 2003. Manures for organic crop production. Http;www.attra.mcat.org/attra-pub/PDF/manures.pdf . Fundamentals ofSustainable Agriculture. Appropriate technology transfer for rural areas(ATTRA).U.S.A.

Khan, G.S. 1998. Soil salinity/sodicity status in Pakistan. Soil Surveyof Pakistan, Lahore. pp.19.
http://www.attra.mcat.org/attra-pub/PDF/manures.hdfhttp://www.attra.mcat.org/attra-pub/PDF/manures.hdf


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Table 1: Analysis of Different Organic Materials Used in Various Experiments

Sr.No.

Determinations Unit FYM Sesbania Compost

1 pH (1:1) - 8.05 6.60 7.67

2 EC (1:1) dS.m -1 12.78 5.92 6.31

3 Organic matter % 40.36 46.86 48.15

4 Organic carbon % 23.47 27.24 28.00

5 Total nitrogen % 1.80 1.90 2.10

6 C/N ratio - 13.04 14.33 13.33

7 Calcium g.kg -1 12.4 15.5 18.6

8 Magnesium g.kg -1 4.7 5.3 6.6

9 Potassium g.kg -1 14.3 40.5 13.3

10 AvailablePhosphorus

g.kg -1 7.0 11.5 14.8

11 Chlorides g.kg -1 4.48 4.21 5.35


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Table 2: Original Soil Analysis of Pot and Field Experiments

Sr.No.

Determinations Unit Normal soil Salt-affected(saline sodic)

soil

1 Saturation percentage % 38.95 42.29

2 pH s - 8.15 8.63

3 ECe dS.m -1 2.35 4.95

4 CO3-2 m mol c L-1 Nil 2.50

5 HCO 3-1 m mol c L-1 7.00 13.50

6 Cl-1 m mol c L-1 4.15 14.00

7 SO4-2 m mol c L-1 12.35 19.50

8 Ca+2 + Mg +2 m mol c L-1 8.60 9.05

9 Na +1 m mol c L-1 14.90 40.45

10 SAR (m mol L -1)1/2 7.20 18.99

11 Gypsum requirement(GR)

t.acre -1 Nil 3.50

12 Sand % 60.00 56.00

13 Silt % 20.00 20.00

14 Clay % 20.00 24.00

15 Textural class - Sandy clayloam

Sandy clayloam

16 Organic carbon % 0.20 0.12

17 Organic matter % 0.35 0.20

18 Total Nitrogen % 0.02 0.01


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Table 3 Nutrient Supplementation to first rice crop (2003) through Compost inNormal Soils (field experiment)

Treatments Max. PlantHeight (cm)

No. of fertiletillers/plant.

Totalbiomass

(t ha -1)

Grain yield(t ha -1)

T1-Control 117.3 20.0 D 12.54 C 2.41 C

T2-Recommendeddose of NPK

124.0 25.3 B 14.22 AB 3.00 A

T3-Compost@ 20 t.ha-1

129.3 29.3 A 14.92 A 3.09 A

T4- Recommendeddose of NPK +Compost @ 10 t.ha -1

121.3 23.3 C 13.75 AB 2.89 A

T5-Compost@ 10 t.ha-1 +Straight fertilizer

119.5 NS 22.8 C 13.00 B 2.65 B

Table 4 Nutrient Supplementation to first wheat crop (2003-04) throughCompost in Normal Soils (field experiment)



Totalbiomass(t ha -1)

Grain yield(t ha -1)

Control 99.25 6.35 C 7.95 C 2.69 C

Recommended dose ofNPK

106.75 7.28 B 11.24 B 4.20 B

Compost @ 20 t ha -1 107.50 8.05 A 12.63 AB 4.59 AB Recommended doseof NPK +Compost @10 t ha -1

108.25 8.93 A 14.25 A 5.00 A

Compost @ 10 t ha -1 +Straight fertilizer

106.25 NS 7.50 B 11.33 B 4.27 B


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Table 5 Nutrient Supplementation to second rice crop (2004) through Compostin Normal Soils (field experiment)



Totalbiomass

(t ha -1)

Paddy yield(t ha -1)

T1-Control 115.5 B 18.25 C 7.94 E 1.82 E


118.5 B 20.50 BC 9.75 D 2.80 D

T3-Compost @ 20 t.ha -1 125.8 A 27.50 A 13.80 A 3.79 AT4- Recommendeddose of NPK +Compost @ 10 t.ha -1

119.0 B 22. 75 B 13.50 B 3.63 B

T5-Compost @ 10 t.ha -1

+ Straight fertilizer

117.5 B 19.00 C 12.22 C 2.99 C

Table 6 Nutrient Supplementation to second wheat crop (2004-05) throughCompost in Normal Soils (field experiment)



Totalbiomass(t ha -1)

Wheat Grainyield(t ha -1)

T1-Control 98.00 C 6.15 C 8.31 E 2.66 E


104.25 B 6.82 BC 11.31 D 3.47 D

T3-Compost @ 20 t.ha -1 106.50 AB 7.75 AB 12.31 B 3.90 BT4- Recommendeddose of NPK +Compost @ 10 t.ha -1

107.00 A 8.50 A 12.89 A 4.76 A

T5-Compost @ 10 t.ha -1 + Straight fertilizer

104.50 B 7.20 ABC 11.55 C 3.63 C


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Table 7 Effect of compost on soil properties in nutrient supplementation afterfirst rice crop (field experiment)

Treatments pH s ECe (dSm -1)

SAR Organicmatter

(%)

Phosphorus

(ppm)

Potash(ppm)

T1-Control 8.17 A 2.43 14.85 A 0.49 C 4.14 D 19.0 D


8.15 A 2.55 13.42 A 0.74 B 9.85 C 36.0 C


7.71 B 3.64 3.71 B 1.16 A 13.73 B 55.0 A

T4-Recommendeddose of NPK +

Compost @ 10t.ha -1

7.85 B 3.48 4.05 B 1.06 A 16.60 A 44.0 B

T5-Compost@ 10 t.ha-1 +Straightfertilizer

7.95 B 3.63 NS 5.86 B 0.94 A 9.40 C 38.0 C

Table 8 Effect of compost on soil properties in nutrient supplementation afterfirst wheat crop (field experiment)

Treatments pH s ECe (dSm -1) SAR Organicmatter(%)

Phosphorus(ppm)

Potash(ppm)

T1-Control 8.20 A 2.50 13.46 A 0.61 B 5.53 C 22.0 C


8.18 A 2.52 13.25 A 0.83 B 10.56 B 39.0 BC


7.65 B 3.72 4.52 B 1.23 A 16.24 A 61.0 A

T4-Recommendeddose of NPK +Compost @ 10t.ha -1

7.85 B 3.19 5.19 B 1.17 A 17.76 A 53.0 A


7.86 B 3.26 NS 5.62 B 0.97 A 12.35 B 42.0 AB


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Table 9 Effect of compost on soil properties in nutrient supplementation aftersecond rice crop (field experiment)


SAR Organicmatter(%)

Phosphorus(ppm)

Potash(ppm)

T1-Control 8.21 A 2.54 C 14.25 A 0.55 C 5.30 E 20.0 D


8.19 A 2.58 C 13.75 B 0.85 B 10.00D

38.5 C


7.68 C 3.70 A 5.50 E 1.20 A 14.55 B 58.6 A


Compost @ 10t.ha -1

7.97 B 3.50 AB 6.35 D 1.10 A 16.90 A 50.0 B


8.00 B 3.45 B 7.20 BC 0.95 B 10.75 C 37.0 C

Table 10 Effect of compost on soil properties in nutrient supplementation aftersecond wheat crop (field experiment)

Treatments pH s ECe

(dSm-1

)

SAR Organic

matter(%)

Phospho

rus(ppm)

Potash

(ppm)T1-Control 8.25 A 2.46 D 14.10 A 0.53 D 5.26 E 18.60 E


8.17 B 2.53 CD 13.70 B 0.80 C 10.19 D 37.30 D


7.92 D 3.18 A 6.15 E 1.18 A 15.00 B 57.70 A


8.03 C 2.76 B 7.20 D 1.11 A 16.35 A 51.50 B


8.03 C 2.63 C 8.35 C 0.93 B 11.45 C 40.25 C


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Table 11 Nutrient Supplementation to first rice crop (2003) through Compost inNormal Soils (pot experiment)



Totalbiomass

(g pot -1)

Paddy yield(g pot -1)

T1-Control 83.75 3.17 C 17.87 C 3.59 D


99.25 9.67 B 48.74 B 11.63 C

T3-Compost @ 20 t.ha -1 101.75 16.92 A 76.16 A 18.53 AT4- Recommendeddose of NPK +Compost @ 10 t.ha -1

103.25 18.83 A 91.46 A 20.86 A

T5-Compost @ 10 t.ha -1

+Straight fertilizer

100.00

NS

16.33 A 64.00 AB 14.96 B

Table 12 Nutrient Supplementation to first wheat crop (2003-04) throughCompost in Normal Soils (pot experiment)



Totalbiomass(g pot -1)

Wheat Grainyield

(g pot -1) T1-Control 69.50 3.50 B 22.04 B 11.15 B

T2-Recommendeddose of NPK 73.0 4.91 A 43.85 A 25.26 AT3-Compost @ 20 t.ha -1 76.50 5.75 A 48.17 A 29.25 AT4- Recommendeddose of NPK +Compost @ 10 t.ha -1

80.25 6.66 A 52.28 A 30.90 A

T5-Compost @ 10 t.ha -1 + Straight fertilizer

75.25NS

5.08 A 47.71 A 27.95 A


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Table 15 Effect of compost on soil properties in nutrient supplementation afterfirst rice crop (pot experiment)


SAR Organicmatter

(%)

Phosphorus

(ppm)

Potash(ppm)

T1-Control 8.42 A 2.62 13.80 0.21 C 5.26 C 22.0 C


8.37 B 2.60 12.35 0.43 B 12.76 B 33.0 B


8.26 B 3.05 10.42 0.89 A 16.29 A 58.0 A


Compost @ 10t.ha -1

8.32 B 2.85 11.76 0.74 A 10.35 B 54.0 A


8.35 B 2.91NS

11.90 NS 0.76 A 10.20 B 53.0 A

Table 16 Effect of compost on soil properties in nutrient supplementation afterfirst wheat crop (pot experiment)

Treatments pH s ECe

(dSm-1

)

SAR Organic

matter(%)

Phosphor

us(ppm)

Potash

(ppm)T1-Control 8.45 A 2.60 13.65 A 0.25 C 5.52 C 24.0 C


8.23 B 2.57 10.09 B 0.51 B 14.67 AB 35.0 B


8.09 B 3.26 7.65 B 0.93 A 18.12 A 62.0 A


8.18 B 2.89 8.25 B 0.86 A 11.62 B 60.0 A


8.20 B 2.75NS

8.87 B 0.80 A 11.05 B 58.0 A


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Table 17 Effect of compost on soil properties in nutrient supplementation aftersecond rice crop (pot experiment)


SAR Organicmatter

(%)

Phosphorus

(ppm)

Potash(ppm)

T1-Control 8.44 A 2.65 C 14.00 A 0.24 C 5.35 D 23.0 E


8.40 A 2.61 C 13.25 B 0.45 B 13.20 B 36.0 D


8.20 C 3.18 A 8.48 E 0.90 A 17.00 A 60.0 A


Compost @ 10t.ha -1

8.28 BC 3.00 AB 10.50 D 0.88 A 10.65 C 55.0 B


8.30 B 2.85 B 11.00 C 0.75 A 10.70 C 50.0 C

Table 18 Effect of compost on soil properties in nutrient supplementation aftersecond wheat crop (pot experiment)

Treatments pH s ECe

(dSm-1

)

SAR Organic

matter(%)

Phospho

rus(ppm)

Potash

(ppm)T1-Control 8.44 A 2.65 C 14.15 A 0.23 D 5.30 D 23.8 E


8.40 AB 2.61 C 13.53 A 0.41 C 14.00 B 37.0 D


8.24 C 3.12 A 11.24 C 0.87 A 17.30 A 58.7 A


8.36 B 2.92 B 12.62 B 0.82 A 11.00 C 56.4 B


8.34 B 2.95 B 12.00 BC 0.73 B 11.21 C 54.2 C


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Table-19: Effect of Different Levels of Compost and Gypsum on Yield and YieldParameters of first Rice crop (2003) in Saline Sodic Soil (FieldExperiment)

Treatments Maximum plantheight (cm)

Total biomass(t. ha -1)

Rice grain yield(t. ha -1)

T1-Control 84.50 D 6.80 F 1.00 DT2-Gypsum @ 100 % G.R. 93.50 C 11.60 E 2.26 CT3-Compost @ 24 t ha -1 98.50 C 12.45 E 2.53 CT4-Gypsum @ 100 % G.R.+Compost @ 24 t ha -1

125.50 A 20.31 A 3.85 A

T5-Gypsum @ 100 % G.R.+ Compost @ 12 t ha -1

122.00 A 18.78 B 3.60 A


114.25 B 14.95 C 3.09 B


100.00 C 13.83 D 2.58 C

Table 20: Effect of Different Levels of Compost and Gypsum on Yield and YieldParameters of first wheat crop (2003-04) in Saline Sodic Soil (FieldExperiment)

Treatments Maximumplant height(cm)

No. of fertiletillers / plant

Totalbiomass ofwheat

Grain yieldof wheat(t.ha -1)

T1-Control 99.25 B 6.35 D 7.37 E 2.13 ET2-Gypsum @ 100 %G.R.

105.00 AB 7.78 C 9.97 CD 3.28 D

T3-Compost @ 24 t ha -1

107.50 A 7.90 C 8.62 DE 3.38 CD

T4-Gypsum @ 100 %G.R. +Compost @ 24 tha -1

110.50 A 9.35 A 11.96 AB 4.75 A

T5-Gypsum @ 100 %G.R. + Compost @ 12

t ha-1

108.25 A 8.35 BC 11.23 ABC 4.08 B

T6-Gypsum @ 50 %G.R.+ Compost @ 24 tha -1

108.00 A 8.93 AB 12.89 A 3.91 B

T7-Gypsum @ 50 %G.R. + Compost @ 12 tha -1

106.00 A 8.05 C 10.07 BCD 3.77 BC


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Table 21: Effect of Different Levels of Compost and Gypsum on Yield andyield Parameters of Second Rice crop (2004) in Saline Sodic Soil(Field Experiment)

TreatmentsMaximum plant

height (cm)Total biomass

(t. ha -1)Paddy yield

(t. ha -1)

T1-Control 87.00 G 7.41 D 1.38 D

T2-Gypsum @ 100 % G.R. 97.75 F 14.47 C 4.13 C

T3-Compost @ 24 t ha -1 105.50 E 15.22 B 4.36 C

T4-Gypsum @ 100 % G.R.+Compost @ 24 t ha -1

137.50 A 16.87 A 5.46 A


128.25 B 16.71 A 5.35 A


120.50 C 16.38 A 4.97 AB


110.50 D 15.53 B 4.46 BC

Table 22: Effect of Different Levels of Compost and Gypsum on Yield andyield Parameters of second wheat crop (2004-05) in Saline SodicSoil (Field Experiment)

TreatmentsMaximum plant

height (cm)Total biomass

(t. ha -1) Wheat grain

yield(t. ha -1)

T1-Control 97.69 D 5.13 F 1.28 G

T2-Gypsum @ 100 % G.R. 103.00 C 6.36 E 1.65 F

T3-Compost @ 24 t ha -1 104.00 BC 6.60 E 1.98 E

T4-Gypsum @ 100 % G.R.

+Compost @ 24 t ha -1

107.90 A 9.36 B 2.76 B


105.00 B 8.61 C 2.57 C


105.50 B 10.04 A 3.78 A


103.50 C 7.89 D 2.22 D


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Table 23: Effect of Different Levels of Compost and Gypsum on ChemicalProperties of Saline Sodic Soil after first Rice crop (Field Experiment)

Treatments pH s ECe (dS m -1)

SAR(mmol. L -1)1/2

Organicmatter

(%)

Phosphorus

(ppm)

Potash(ppm)

T1-Control 8.80 6.85 A 32.8 A 0.55 C 4.72 C 29.0 C

T2-Gypsum @100 % G.R.

8.40 4.62 B 16.8 B 0.70 B 13.04 B 40.0 B

T3-Compost@ 24 t ha-1

8.30 4.05 C 13.4 CD 0.88 A 16.18 AB 56.0 A

T4-Gypsum @100 % G.R.+Compost @24 t ha -1

8.20 3.91 C 10.3 E 0.99 A 27.55 A 72.0 A

T5-Gypsum @100 % G.R.+ Compost @12 t ha -1

8.30 4.15 C 12.5 D 0.86 A 18.35 AB 45.0 B


+ Compost @24 t ha -1

8.40 4.10 C 14.3 C 0.92 A 21.18 A 60.0 A

T7-Gypsum @50 % G.R.+ Compost @12 t ha -1

8.20

N.S.

3.85 C 14.9 C 0.80 AB 13.51 B 43.0 B


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Table 24: Effect of Different Levels of Compost and Gypsum on ChemicalProperties of Saline Sodic Soil after first wheat (Field Experiment)

Treatments pH s ECe (dS.m -1)

SAR(mmol.L -

1)1/2

Organicmatter(%)

Phosphorus(ppm)

Potash(ppm)

T1-Control 8.65 A 6.39 A 22.63 A 0.65 C 6.04 C 33.0 E

T2-Gypsum@ 100 % G.R.

8.29 BC 3.97 B 12.47 B 0.73 C 17.21 B 45.0 DE

T3-Compost@ 24 t ha-1

8.20 D 3.94 B 11.53 B 1.05 AB 23.58 A 63.0 BC

T4-Gypsum@ 100 % G.R.

+ Compost@ 24 t ha-1

8.06 E 1.76 C 9.54 B 1.30 A 31.39 A 77.0 A

T5-Gypsum@ 100 % G.R.+ Compost@ 12 t ha-1

8.19 D 1.89 C 11.07 B 1.14 AB 22.65 A 50.0 CD

T6-Gypsum@ 50 % G.R.+ Compost @24 t ha -1

8.32 B 3.71 B 10.62 B 1.13 AB 26.30 A 69.0 B

T7-Gypsum@ 50 % G.R.+ Compost @12 t ha -1

8.23 CD 3.57 B 11.29 B 0.96 B 16.66 B 48.0 D


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Table 25: Effect of Different Levels of Compost and Gypsum on ChemicalProperties of Saline Sodic Soil after Second Rice crop (FieldExperiment)

TreatmentspH s ECe

(dS. m -1)

SAR(mmol. L -1)1/2

Organicmatter

(%)

Phosphorus

(ppm)

Potash(ppm)

T1-Control 8.75 A 6.73 A 32.0 A 0.53 D 4.29 G 30.0 E


8.44 B 4.50 B 16.2 B 0.74 C 12.84 F 41.5 D

T3-Compo

Documents

Final Report Appropriate Composting Technology Project PSF 2006