A Dissipative Hydrological Model for Oasis in Arid Area

TANG, QiuhongTANG, Qiuhong

Oki/Kanae Lab.Oki/Kanae Lab.

The University of TokyoThe University of Tokyo

2003-112003-11

IHWR, Tsinghua Univ. IHWR, Tsinghua Univ.

2003-062003-06

About the model

Water & Salt Balance Model

World Bank projects in Tarimu River

I developed the model by making the water cycle relations more reasonable ,

adding the soil water module,

putting it into action.

BackgroundBackground

About the model

The key of sustainable development of arid area is water resources. A model for arid area will do favor for water resources management.

There are lots of famous conceptual hydrological model such as Standford, Sacramento, Tank… These models can work well at humid area.

A model for arid areaA model for arid area

Water cycle in river basin

A model focus on dissipative flowA model focus on dissipative flow

River basin in arid areaPh

Ps

Eh

Es出山口

产汇流区

耗散流区

P<<E P>E

RFA(Runoff flow area)

DFA(Dissipative flow area )

a mountainous area plain area

The region, a lake or a stream， a waterway， a reservoir supplies to water, or a lake or a stream， a waterway， a reservoir receives runoff which originates from precipitation.

watershed

Difference between dissipative flow model and runoff model

Research area is arid area .Usually, a dissipative flow model need not a module to simulate runoff, but it need a dissipative flow module.Human activities(irrigation, pumping groundwater,..) must be considered.Evaporation should been calculated more precisely. (soil water, crop, irrigation, management level…)

Profile of water cycle in DFA

耕地蒸发

林草地

蒸发

洼地蒸发

裸地蒸发

水库蒸发

河段蒸发

河段渗漏->农区 非农区

耕地蒸发

侧向入流

渗 漏

->农区 非农区 河段渗漏降水

channel water

River seepage Groundwater exchange

drainage

Agriculture area Agriculture area Non-agriculture area Non-agriculture area

Irrigated cropNon-Irrigated cropLowlandNaked land River Reservoir

•River is the main water supplier.•The transfer between atmospheric moisture, surface water, soil water and groundwater is very complex, and the dissipative flow is distinguished.

Precipitation

Water surface Water surface

Water decentralization in DFA

引水渠

河段入流 出流

渗漏

入流

出流

林草地

排水渠

排水

排水

泉

泉

水库 耕地

研究区内外地下水交换drainage

Reservoir

channel

Irrigated crop Non-Irrigated crop

Groundwater flow

Spring/well

channel

Riverinflow outflow

seepage

Framework of the model

排水 排水

I I GGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

Framework of the model

Atmosphere

Soil water

Groundwater

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

排水 排水

IIGGCHGCH

土 壤

地下水

土 壤

地下水

土 壤

地下水

土 壤

地下水

裸 地 林草地 洼地沼泽 农林草

灌溉地 非 灌 溉 地

水 库 泉

河道

河段

井

裸地蒸发 河道蒸发水库蒸发灌溉地蒸发洼地沼泽蒸发 林草地蒸发

EG FGW

DW排水

人、畜

人畜耗水

Groundwater exchange

Agriculture area Non-agriculture area

IrrigatedNon-Irrigated LowlandNaked RiverReservoir

Water surface

Soil Soil Soil Soil

Industry

GW GW GW GW

Reservoir

River

Spring Well

Drainage Drainage

Drainage

Channel water

River seepage

Industry

Naked land Non-Irrigated Lowland Irrigated

Framework of the model

12

3

1. Agriculture area module

I,P: irrigation water, precipitationEU,EM: evaporation of Up-Soil layer and Down-Soil layerEG:groundwater supplying soil waterFWM:seepage water to Down-Soil layerFGW:seepage water to groundwaterIGW:groundwater from river, reservoir, …IIG:groundwater exchange between Agriculture area and Non-agriculture area

DR: drainage

E =EU+EM

GW地下水

WUM

WMM

WU

WM

I +PEU

FWM

EM

FGW

EG

I GW I I G

EU EM mm/ EG、 分别为上、下土壤层蒸散发， 月； 为mm/ WUM WMM毛管水上升补给作物水量， 月； 、 分别mm WU WM为上、下土壤层蓄水容量， ； 、 分别为上土

mm FWM壤层、下土壤层蓄水量， ； 为上土壤层渗入mm FGW下土壤层水量， ； 为下土壤层渗入地下水库

mm I GW / I I G水量， ； 为地下水侧向补给，万方 月；/ DR为农区非农区地下水交换量，万方 月； 为地下

/水排水，万方 月。

DR

渠系渗漏补给C

ha

nn

el S

ee

pa

ge

E

Note:All these parameters use water depth, unit: millimeter/ month.

Up-Soil

Down-Soil

Groundwater

Ea: Evaporation Ability

Let evaporation ability be Ea, potential evaporation be Ep, crop coefficient be Kc, then: Ea=Ep*Kc

Ep(FAO, Penman-Monteith )

Kc

2

2

2 34 . 0 1

273 900

34 . 0 1

1

U r

T e e rU

U r

G R

L Ep d a n

E=EU+EM

}

{

then If

then If

EMEUE

Surplus_EaWMM

WMEM

Ea-WUSurplus_Ea

WUEU

EaWU

EaEEaWU

EG:groundwater to Down-Soil layer

a Ddw 0 e E EG=Flux

a Dw 0 e E GFlux

DdwFl ux Gfl ux

ET_Kc

Dw

Dw

Ea

E0: Water surface evaporation

Phreatic water evaporation:

DR:drainage

We assume it is Dupuit flow, and use the Dupuit equation :

H0

IH

q

L

hH△

0 02

kq h IH h H H IH

L

0 022

2

q kH dt dt h IH H H IH

L L

0 022

2

kDR H A dt h IH H A H IH

L

Drain

Field

2. Non-agriculture area module

Non- i rri gated Naked l and l owl and …

Evaporati on

GN

IIG

GN: Seepage from ri ver, reservoi r, channel；

IIG: Groundwater exchange from agri cul ture area ；GCH为各种土 GCH: Groundwater exchange i nner non- agri cul ture area

GCH GCH GCH

Drai nage

Non-agriculture area Evaporation

a Ddw 0 e E Flux a Dw

0 e E GFlux E0

3. Groundwater Exchange System

Type1 Type…

Type3Type2

Also we assume it is Dupuit flow, and use the Dupuit equation to estimate groundwater exchange

Applications of ModelBased on the research on the pilot area of Akesu River basin oasis in northwest China, I will introduce the development and application of the dissipative hydrological model for arid oasis.

Both the evaporation in agriculture area and in non-agriculture area as well as groundwater exchange from Jan 1999 to Dec 2002 in Akesu River basin oasis are calculated by the model.

Research area

Tarimu River

Akesu River

Area: 12,000km2 Precipitation: 30-90mm/yearWater-surface evaporation : 1100-1300mm/year

Sketch of Research Area

阿拉尔

西大桥

温宿县

协合拉

乌什县

阿瓦提县

阿克苏市

沙里桂兰克

U1U2

U3

U4

U5

U6

Shaliguilanke

Xiehela

Alaer

Sketch of riverway

Legend

Station

Reservoir

Riverway

Comparison of the simulated and recorded hydrograph at Xidaqiao Station

Comparison of the simulated and recorded hydrograph at Yimapaxia Station

Comparison of the simulated and recorded hydrograph at Alaer Station 0

2468

101214161820

J an- 99 J ul - 99 J an- 00 J ul - 00 J an- 01 J ul - 01 J an- 02 J ul - 02

10径流量（

8 m3 ）

计算出流实测出流

simulated

observed

run

off

02468

101214161820

J an- 99 J ul - 99 J an- 00 J ul - 00 J an- 01 J ul - 01 J an- 02 J ul - 02

10径流量（

8 m3 ）

计算出流实测出流

simulated

observed

run

off

0

5

10

15

20

25

30

35

J an- 99 J ul - 99 J an- 00 J ul - 00 J an- 01 J ul - 01 J an- 02 J ul - 02

10径流量（

8 m3 ）计算出流实测出流

simulated

observed

run

off

Water table

Comparison of the simulated and observed water table at Unit 3

Comparison of the simulated and observed water table at Unit 4

0. 00

0. 50

1. 00

1. 50

2. 00

2. 50

3. 00

J an-99 J ul -99 J an-00 J ul -00 J an-01 J ul -01 J an-02 J ul -02

模拟实测

simulated

observed

0. 00

0. 50

1. 00

1. 50

2. 00

2. 50

3. 00

3. 50

J an-99 J ul -99 J an-00 J ul -00 J an-01 J ul -01 J an-02 J ul -02

模拟实测

simulated

observed

Result: main water cycle

2.8 13.1 2.8 25.7 7.6 0.2 2.9 2.8

69.4

4.1

River

1.5

Notes:

Unit: 108m3/year.Based on the data of 1999 -2002 in Akesu river basin.

Naked Land

Non-

irrigated Crop Land

Reservoir OutsideLowlandIrrigated

LandChannel

Industry,

Rural water

supply

27.09

5.01 6.59

19.9Drain

Result14%

5% 47%

24%

5%

5%

Agri cul ture area Non- i rri gated crop Naked l and

Lowl and Reservoi r Channel

Summary

Out of the results in Akesu river basin, we can draw conclusion that the model works well in Akesu river basin which is a representative plain oasis in arid area, and more applications of the model in northwest China may be possible.

Further Research

The model, based on a typical DFA, focus on dissipative flow, runoff flow is simplified. How to establish a model which focus on both dissipative flow and runoff flow?The groundwater exchange system is complex, and it is hard to distribute groundwater to land types.It is hard to ascertain some parameters, such as drainage coefficient and channel coefficient.A model system is required.My colleagues are employing the model to other basin (Hetianhe river, Weiganhe river, Kai-konghe river )in Xinjiang. I will develop the model according to the applications.