Effects of phosphorus fertilization and liming on growth, mineral nutrition, and gas exchange of Alnus rubra seedlings grown in soils from mature alluvial Alnus stands

Effects of phosphorus fertilization and liming ongrowth, mineral nutrition, and gas exchange ofAlnus rubra seedlings grown in soils from maturealluvial Alnus stands

K.R. Brown and P.J. Courtin

Abstract: In southern coastal British Columbia, red alder (Alnus rubra Bong.) is recommended for reforestation onsome low-elevation, fertile, and moist sites (e.g., alluvial sites). Correlative data indicate that P deficiencies limit thegrowth of alder in low-pH soils; deficiencies of P and other elements may also develop in the presence of an alderstand. Because alder may be grown in repeated rotations on alluvial sites, we sought to determine whether elementaldeficiencies were likely in soils from mature stands. We examined the effects of P additions (as triple super phosphate)and liming (as dolomitic limestone) on potted red alder seedlings grown in soils from mature alluvial alder stands.Four soils were “low-pH” (mean = 4.5) and two were “high-pH” (mean = 5.5); all were classified as very rich. Growthof unfertilized seedlings was greatest in the soil with the highest soil Bray-P levels. Growth rates increased with P sup-ply, but the response decreased with increasing Bray-P and was less in the high-pH soils. Liming increased soil pH anduptake of Mg, but did not increase growth. Phosphorus additions increased growth mainly by increasing P uptake, leafsize, and biomass allocation to branches. Photosynthetic rates were highest in the intermediate P treatment, but instan-taneous water use efficiency increased with P rate. Phosphorus deficiencies may limit the growth of alder seedlings inalluvial soils previously containing mature alder stands.

Résumé : Dans la zone côtière du Sud de la Colombie-Britannique, l’aulne rouge (Alnus rubra Bong.) est recommandépour la reforestation sur certains sites fertiles et humides situés à basse altitude (e.g. les sites alluviaux). Les analysesde corrélation indiquent que les déficiences en phosphore (P) limitent la croissance de l’aulne dans les sols à pH bas;des déficiences en P et en d’autres éléments peuvent aussi se développer dans les peuplements d’aulne. Parce quel’aulne peut être cultivé en rotations successives sur les sites alluviaux, nous avons cherché à déterminer si des défi-ciences pouvaient survenir dans les sols occupés par des peuplements matures. Nous avons mesuré les effets d’apportsde P (sous forme de superphosphate triple) et du chaulage (sous forme de chaux dolomitique) sur des semis en potscultivés dans des sols alluviaux de forêts matures d’aulne. Quatre sols avaient un pH bas (moyenne = 4,5) et deux au-tres avaient un pH élevé (moyenne = 5,5); tous étaient classés comme très riches. La croissance des semis non fertili-sés était la plus forte dans les sols avec les plus hauts niveaux de P-Bray. Le taux de croissance a augmenté avec lesapports de P, mais la réponse a diminué avec l’accroissement de P-Bray et était moindre dans les sols à pH élevé. Lechaulage a accru le pH du sol et le prélèvement de Mg mais n’a pas augmenté la croissance. Les apports de P ontaugmenté la croissance, surtout en augmentant l’assimilation de P, la dimension des feuilles et l’allocation de biomasseaux branches. Le taux de photosynthèse était le plus élevé dans le traitement intermédiaire de P, mais l’efficacité ins-tantanée de l’utilisation de l’eau a augmenté avec le taux de P. Les déficiences en P peuvent limiter la croissance dessemis d’aulne dans les sols alluviaux déjà occupés par des peuplements matures d’aulne.

[Traduit par la Rédaction] Brown and Courtin 2096

Introduction

Red alder (Alnus rubra Bong.) is the most widespreadnative deciduous tree species of the coastal forest of north-western North America. In British Columbia, red alder ag-gressively colonizes disturbed sites, especially those that aremoist and fertile, in the Coastal Western Hemlock (CWH)biogeoclimatic zone (Klinka et al. 1990). Rapid potentialgrowth rates, immunity to Phellinus weirii (Thies andSturrock 1995), an ability to fix atmospheric N2 (Binkley etal. 1994), and increasing use in value-added products(Massie et al. 1994) have encouraged efforts to grow alderon appropriate sites. Red alder is sensitive to moisture stress

Can. J. For. Res. 33: 2089–2096 (2003) doi: 10.1139/X03-125 © 2003 NRC Canada

2089

Received 11 June 2002. Accepted 25 April 2003. Publishedon the NRC Research Press Web site at http://cjfr.nrc.ca on21 October 2003.

K.R. Brown.1,2 Research Branch, British Columbia Ministryof Forests, P.O. Box 9519, Stn. Prov. Govt., Victoria,BC V8W 9C2, Canada.P.J. Courtin. Coast Regional Office, British ColumbiaMinistry of Forests, 2100 Labieux Road, Nanaimo, BCV9T 6E9, Canada.

1Corresponding author (e-mail: [email protected]).2Present address: K.R. Brown and Associates, 4043 ZinniaRoad, Victoria, BC V8Z 4W2, Canada.

I:\cjfr\cjfr3311\X03-125.vpOctober 20, 2003 11:55:16 AM

Color profile: Generic CMYK printer profileComposite Default screen

(Pezeshski and Hinckley 1988). Alluvial sites may be of par-ticular interest to manage for alder because soil moisture re-gimes are often favorable for growth (Harrington andCourtin 1994) and because the presence of fast-growingcompeting vegetation makes conifer establishment difficult(Green and Klinka 1994).

Nutritional deficiencies may limit the growth and N -2fixing ability of red alder even on fertile sites. On rich orvery rich sites (Green and Klinka 1994) in coastal BritishColumbia, site indices of alder increased with foliar P con-centrations and with extractable P levels in soils of pH <4.4(Courtin 1992). Fertilization of planted alder with P in-creased stem volumes (Brown 1999). Nitrogen-fixing plantsmay have higher P requirements than their non-N2-fixing as-sociates (Sprent 1988), although this has not been shown forred alder. Nodulation and N2 fixation may be inhibited bydeficiencies of P, K, Ca, Mg, and Mo in acidic soils(Marschner 1995) and the presence of an alder stand mayexacerbate such deficiencies if the stand is harvested and re-planted to alder, as shown on an upland site (Cole et al.1990; Compton et al. 1997). However, deficiencies may notalways become more pronounced in the presence of alder(e.g., Bormann et al. 1994; Giardina et al. 1995). Since re-peated rotations of alder are a management option for allu-vial sites, it is important to assess the potential for nutrientdeficiencies on such sites.

In this study, we assessed soils from six alluvial red alderstands on Vancouver Island for potential nutrient limitationsto alder seedling growth. We used a bioassay approach be-cause appropriate field sites were unavailable. We thoughtthat growing alder seedlings in soil from mature alder standsmight indicate whether elemental deficiencies were possiblefor seedlings grown in a subsequent rotation. Our objectiveswere to determine whether (1) alder seedling growth variedwith soil pH and elemental supply; (2) additions of P anddolomitic lime increased the growth of potted alder seed-lings grown in soil collected from mature alder stands; and(3) effects of fertilization varied with site and, particularly,with soil pH. Gas exchange rates and tissue elemental con-centrations were measured to better understand growth re-sponses following nutrient additions.

Materials and methods

Sites and soilSoil was collected from six mature alluvial red alder

stands on Vancouver Island (Table 1) that had been studiedpreviously (Courtin 1992). Soils from four stands were clas-

sified as “low pH” and the remaining two as “high pH.” Allsoils were sandy loam or silt loam, had few coarse frag-ments, and were classified as “very rich” (Green and Klinka1994). Mineral soil was collected in November at 0–15 cmdepth from four to six points within each stand, composited,and transferred to the laboratory. Subsamples were air-driedand used for physical and chemical analyses, including thedetermination of pH. The remaining soil was screened(0.6 cm) and placed in 3-L (15 cm top diameter) pots.

Seedling cultureRed alder seed from Vancouver Island was germinated in

sand in March. Seedlings were lifted in May, at which timelengths averaged 5 cm and fresh masses 0.74 g. Moisturecontents were determined on a subset of seedlings afteroven-drying. Seedlings were transplanted (one per pot) andtransferred to a glasshouse. Roots of all seedlings werenodulated at the time of transplanting.

The glasshouse was naturally illuminated during daylighthours. Mercury lamps provided supplemental light (maxi-mum 150 µmol·m–2·s–1 canopy level) in early morning andlate evening, giving a daily photoperiod of 18 h. Daily airtemperatures averaged 24.8 °C (range 13.6–34.2 °C), dailyphotosynthetic photon flux density (PPFD) averaged29.2 mol·m–2·d–1 (range 8.2–40.9 mol·m–2·d–1), and maxi-mum midday (1000–1400 hours) PPFD averaged818 µmol·m–2·s–1 (range 171–1217 µmol·m–2·s–1). Middaymean vapor pressure deficits averaged 1.84 kPa (range of0.91–2.87 kPa). Pots were surface-irrigated as necessary tomaintain moist rooting zones.

Fertilization treatmentsWe applied three levels of triple super phosphate (TSP, 0–

45–0) and two levels of dolomitic lime (22% Ca; 10% Mg;neutralizing value of 96%) in factorial combination. Thelime was relatively coarse, with 87% >0.42 mm (40-mesh).The P0, P1, and P2 treatments supplied 0, 0.4, or0.8 g P·pot–1, respectively, (equivalent to 0, 225, or450 kg P·ha–1) and 0, 0.27, or 0.53 g Ca·pot–1. Lime wasadded at 0 (D0 treatment) or 8.8 (D1) g·pot–1 (5 t·ha–1). Thelatter supplied 0.88 g Mg·pot–1 and 1.94 g Ca·pot–1. Eachtreatment was replicated seven times. Fertilization rates werechosen after testing effects of P and D on growth and effectsof D on soil pH in one soil. Fertilizers were added at plant-ing and mixed by hand into the upper 3 cm of soil. Pot loca-tions were randomly assigned at the start of the experimentand not changed thereafter.

© 2003 NRC Canada

2090 Can. J. For. Res. Vol. 33, 2003

pH class SiteAge(years)

SI25

(m)Ah(cm)

C(g·kg–1)

Bray-P(mg·kg–1) pH

Low Sarita 44 25 30 65 8.8 4.7Nitinat 53 23 6 93 10.9 4.4Sayward 45 22 10 151 7.8 4.4Big Tree 49 18 4 92 8.9 4.5

High Cowichan 65 21 14 145 14.9 5.6Klanawa 43 22 5 112 29.3 5.4

Note: Ah, thickness of the Ah horizon; C, soil carbon content.

Table 1. Stand age and red alder site index (SI25) and selected characteristics ofsoils used in the glasshouse experiment.

I:\cjfr\cjfr3311\X03-125.vpOctober 15, 2003 3:28:27 PM


Growth measurementsFollowing transplanting, seedling heights were measured

biweekly. Seedlings were harvested 54 days after transplant-ing and divided into roots, stems, branches, and leaves. Leafareas were determined (Delta-T leaf area measurementsystem, Burwell, Cambridge, U.K.) on four to five of thenewest mature leaves from each plant. All plant parts wereoven-dried at 80 °C for 48 h and weighed. Specific leaf ar-eas (SLA) (Hunt 1990) of sampled leaves and whole plantmasses were used to estimate whole-plant leaf areas. Drymatter allocation to roots (root mass ratio (RMR)) (note thatmass ratio is equivalent to the more commonly used weightratio), stem (stem mass ratio (SMR)), branches (branch massratio (BMR)), and leaves (leaf mass ratio (LMR)) and rela-tive growth rate (RGR) were calculated using standard for-mulae (Hunt 1990). Relative growth rate was calculated foreach seedling for the 54-day growth period. The initial indi-vidual plant dry mass was assumed to be the product of themeasured initial fresh mass and mean initial moisture con-tent.

Gas exchange measurementsNet photosynthetic rates (A), stomatal conductance (Gs),

and transpiration rates (E) were measured on a single re-cently mature leaf on each seedling in the glasshouse fromJuly 8 to July 10 using a LI-6400™ portable photosynthesissystem (LiCor, Inc., Lincoln, Nebr.). Irradiance on the leafwas maintained at 1700 µmol·m–2·s–1. Vapor pressure defi-cits, air temperatures, and CO2 concentrations in the cuvettewere maintained at 1.49 ± 0.02 kPa (mean ± SE), 25.8 ±0.1 °C, and 366 ± 1 µmol·mol–1, respectively. Gas exchangemeasurements were made between 0930 and 1600 hours,and individual plants were measured in random order.

Soil and tissue analysisAt the onset of the trial, subsamples of collected soil were

analyzed for pH (1:1 H2O), extractable P by autoanalyzerafter extraction in Bray P1 extractant (Kalra and Maynard1991), and cation content by inductively coupled argonplasma (ICAP) emission spectrometry after extraction in 1 Nammonium acetate. Following harvest, soils from all potswithin a given site × treatment combination were com-posited and analyzed for pH, P, and BaCl2-extractable K, Ca,Mg, Na, Fe, Mn, and Al. The extraction procedure waschanged because BaCl2 is considered a more suitable ex-tractant of cations in acidic forest soils (Hendershot et al.1993). This change precluded pre- and post-treatment com-parisons of soil exchangeable cation content, however.

Ovendried tissue from each seedling was ground in a cof-fee grinder (leaves) or Wiley mill (roots, stems, branches).Individual plant parts were analyzed for N and C by micro-Dumas combustion (automated NCS analyzer) and P, K, Ca,Mg, S, Fe, B, Mn, Zn, Cu, and Al by ICAP. Whole-plant el-emental concentrations were calculated from the mass andconcentration in each part sampled per plant. Elemental dataare presented on an ovendry basis.

Statistical analysisTreatment effects on seedling growth, nutrition, and gas

exchange were assessed by ANOVA using a split-plot de-sign, with pH class the main-plot factor and P and D the

split-plot factors. Initial mass or height was included as acovariate, as appropriate, for growth and nutrient contentmeasurements. Means were compared by orthogonal con-trast or, for significant interactions, by least significant dif-ferences (LSD) with a Bonferroni correction (Milliken andJohnson 1992). Relationships between growth and nutritionwere analyzed by regression and correlation analysis. Analy-ses were performed using JMP™ 3.2.1 (SAS Institute Inc.,Cary, N.C.).

Results

Unfertilized soils from the Cowichan and Klanawa siteshad greater pH and Bray-P levels than soils from Sarita,Nitinat, Sayward, and Big Tree sites (Table 1). Growth ofunfertilized seedlings increased with soil Bray-P levels(Fig. 1a), as did whole plant P contents r = 0.87, n = 6, P ≤0.05). In unfertilized soils, Bray-P levels were greater at theend of the experiment than at the beginning (Tables 1 and 4;paired t test, P ≤ 0.0006).

Fertilization with P increased seedling growth, and re-sponses of whole-plant mass, leaf area, and leaf numbers toP rate all varied with soil pH class (Tables 2 and 3). The in-crease in whole-plant mass with P addition was least in thesoil (Klanawa) with the highest initial Bray-P level (Fig. 1b).Responses to P addition increased in the following order:root mass (52% and 75% in P1 and P2) < stem mass (71%and 106%), leaf mass (106% and 157%) < branch mass(167% and 232%). Hence, root mass ratio decreased with in-creasing P rate and branch mass ratio increased (Table 3).Leaf (mean = 0.50) and stem (mean = 0.21) mass ratios didnot vary with soil or treatment. Fertilization with P increasedwhole-plant and individual leaf area, did not affect numbersof leaves, and decreased specific leaf area, but only in thelow-pH soils (Table 3).

Fertilization with P increased soil Bray-P and exchange-able Ca concentrations (Table 4), foliar and whole-plant con-centrations of N, P, Ca, and S, and foliar concentrations ofMg and Fe, but decreased foliar concentrations of K, Cu,and Zn (Tables 5 and 6) and whole-plant concentrations ofAl and B (data not shown). Unlike growth responses, the ef-fect of P additions on nutrient concentrations did not varywith pH class, but did vary with site for whole-plant P andfoliar P, K, Ca, S, and Mn (Table 5). Consistent with thegrowth responses, whole-plant P concentrations increasedthe least with P additions in the high-P Klanawa soil. Thesignificant interaction of P and site for foliar K and Ca wasmainly due to the response of seedlings in the Cowichansoil; those seedlings had the highest Ca and lowest K con-centrations in the P0 treatment and the concentrations didnot change with P rate. In contrast to biomass allocation re-sponses, increases in P rate increased P concentrations theleast in foliage (27%) and the most in roots (55%; 1.8–2.8 g·kg–1). Relative growth rate increased with whole-plantP to a maximum at 3–3.5 g·kg–1 (Fig. 2) and also correlatedwith foliar N concentration r = 0.45, n = 245), but correla-tions with tissue concentrations of other elements weremuch weaker. Relative growth rate was much more stronglycorrelated with elemental concentrations than was plantmass (data not shown).

© 2003 NRC Canada

Brown and Courtin 2091

I:\cjfr\cjfr3311\X03-125.vpOctober 20, 2003 11:18:10 AM


Liming did not affect growth. Liming increased soil pHby 0.25 across P treatments, increased exchangeable Ca (inthe absence of added P) and Mg, and decreased exchange-able K, Mn, and Al (Table 4). Liming increased whole-plant(3.4 vs. 3.0 g·kg–1) and foliar Mg (3.8 vs. 3.3 g·kg–1) con-centrations. Liming also decreased foliar K in the Big Treesoil, but did not otherwise affect nutrient concentrations.

Gas exchangePhotosynthetic rates, determined on a leaf area basis (Ala),

were greatest in the P1 treatment (Fig. 3) and correlatedweakly with RGR (r = 0.35–0.47, n = 41, P ≤ 0.03) in allsoils except Klanawa. The Ala increased with foliar P contentto ca. 4.5 mmol P·m–2 (data not shown) in three of the soils,but, in general, was more strongly related to foliar contentsof S, B, K, and Mn. Conductance (Gs) and transpiration (E)were lowest in the P2 treatment; consequently, water use ef-ficiency (A/E) increased with P rate (Fig. 3).

Discussion

Fertilization with triple super phosphate (TSP) increasedthe growth of red alder seedlings grown in soils collectedfrom several alluvial red alder stands on Vancouver Island.The growth responses to P additions were consistent withfirst-year responses in field fertilization studies in young al-der plantations on nonalluvial, rich – very rich sites on east-ern Vancouver Island (Brown 1999) and were in agreementwith field studies that correlated site index of alder with soilcharacteristics. Growth increased with soil Bray-P levels inunfertilized soils to at least 29 mg·kg–1 (Klanawa) and re-sponded the least to P additions in that soil. In field studies,site index increased to a maximum at ca. 30 mg·kg–1 Bray-P(Harrington and Courtin 1994) and site index was morestrongly correlated with available P (and foliar P concentra-tions) in low-pH soils (Courtin 1992). Consistent with thatobservation, effects of P additions were greater in the lower-pH soils in this study.

Growth increases with TSP additions could have been dueto alleviation of P or Ca deficiencies. However, growth rateswere more strongly correlated with tissue concentrations ofP than of other elements. Foliar P concentrations of unfertil-ized trees may have been deficient (<2.2 mg P·kg–1) (Brown2002). Foliar Ca concentrations also increased with growthrate from P0 to P1 in the four most responsive soils. How-ever, foliar Ca in unfertilized seedlings was high comparedwith previous reports for red alder (Radwan and DeBell1994). In the Big Tree soil, liming-only (P0D1) increasedfoliar Ca to concentrations similar to those in the TSP-onlytreatment (P1D0), but did not increase growth. Thus, Ca wasnot deficient, at least in the Big Tree soil.

Growth rates correlated more strongly with whole-plant Pthan with foliar P concentrations. Whole-plant and root plusnodule concentrations of P increased more with P availabil-ity than did foliar P concentrations, consistent with re-sponses of soybean (Freeden et al. 1989) and clover (Hart1989) to increased P supply. Tissue N concentrations andcontents also increased with P supply. It is possible that Ndeficiencies were alleviated by P additions in some soils, ei-ther through increased rates of N2-fixation or mineral N as-similation. Nitrogen deficiencies probably did not occur inthe Nitinat or Big Tree soils; in both, foliar N concentrationswere greater in the P2 than in the P0 treatment without anassociated increase in growth.

Growth responses to increased P uptake appeared morestrongly associated with increased leaf area and allocation tobranches than with increases in net photosynthetic rate (A), apattern consistent with responses in outdoor studies withlarger alder seedlings (Brown 2002). Although A was greater

© 2003 NRC Canada

2092 Can. J. For. Res. Vol. 33, 2003

Fig. 1. Relationships between (a) whole-plant mass of unfertil-ized seedlings and initial soil Bray-P content, and (b) growth in-crease with P addition and soil Bray-P content. All increaseswere significant at P ≤ 0.05, except the P1 treatment in theKlanawa soil. Site abbreviations: C, Cowichan; N, Nitinat; SL,Sarita; K, Klanawa; SY, Sayward; B, Big Tree.

Source df P

pH 1 0.824P 2 <0.001D 1 0.302P × D 2 0.251P × pH 2 0.007D × pH 1 0.799P × D × pH 2 0.910P × S(pH) 8 0.190D × S(pH) 4 0.865P × D × S(pH) 8 0.404

Note: Sources significant for whole-plant mass were alsosignificant for whole-plant and individual leaf area, specificleaf area, and branch mass ratio; leaf and stem mass ratioswere unaffected by treatment and root mass ratio variedwith P only. Other abbreviations: S, soil; P, phosphoruslevel; D, lime (dolomite) level.

Table 2. Analysis of variance summary for whole-plant mass.



in P1 than in P0, A and foliar P concentrations were unre-lated in three of the six soils and weakly related in the otherthree. Foliar P was at the high end of the range over which Aand foliar P were correlated in early successional tropicaltrees (Raaimakers et al. 1995). Photosynthetic rate can belimited by P deficiencies (Marschner 1995; Rodriguez et al.1998), but P supply may limit growth via reduced A only atlow rates of supply. The greater decrease in E, comparedwith A, as P supply increased, was previously reported foralder seedlings (Brown 2002).

Lime additions (at rates similar to that applied here) toblack alder seedlings growing in coarse-textured mine spoilsincreased soil pH from 2.9 to 3.6 and shoot growth in the

presence of added P (Seiler and McCormick 1982). Here,liming did not affect growth, but increased tissue concentra-tions of Mg, while decreasing K and Mn in one or moresoils. This suggests that Mg was not deficient and liming didnot induce deficiencies of K and Mn. Liming increased tissueCa concentrations less than did TSP additions, even thoughCa addition rates were 2.4-fold greater in dolomite than at thehighest rate of TSP addition. Liming increased available soilCa and foliar Mg concentrations; greater uptake of Mg bylimed seedlings may have reduced the uptake of Ca added inthe limestone (e.g., Ljungstrom and Nihlgard 1995).

On low-elevation, fertile, alluvial sites in coastal BritishColumbia, conifer establishment is difficult and repeated ro-

© 2003 NRC Canada


pH class P levelTM(g)

LAt

(dm2)LAi

(cm2)SLA(dm2·g–1) RMR BMR

Low 0 3.37 4.5 39.3 2.9 0.25 0.041 8.36 9.7 54.9 2.5 0.22 0.092 10.17 11.6 57.4 2.5 0.21 0.11

High 0 5.67 7.1 53.1 2.6 0.22 0.061 7.16 9.1 52.5 2.6 0.19 0.082 8.19 10.0 53.5 2.6 0.18 0.08

LSD0.05 1.51 1.5 6.9 0.2 0.04 0.02

Note: Stem and leaf mass ratios did not vary (see text) and are not shown. Bonferroni-corrected least significant differences (LSD0.05) are shown to facilitate comparisons of means.Abbreviations: TM, whole-plant mass; LAt, whole-plant projected leaf area; LAi, projected areaof individual mature leaves; SLA, specific leaf area; RMR, root mass ratio; BWR, branch massratio.

Table 3. Selected growth measurements in relation to site and P rate.

(a) Mean concentrations.

pH class P level D level pHBray-P(mg·kg–1)

K(mg·kg–1)

Ca(mg·kg–1)

Mg(cmol·kg–1)

Mn(cmol·kg–1)

Al(cmol·kg–1)

Low 0 0 4.0 20.7 0.17 4.5 0.8 0.29 5.20 1 4.5 18.5 0.15 6.2 2.1 0.20 2.61 0 4.2 131.6 0.15 6.0 1.0 0.26 3.71 1 4.3 148.5 0.15 7.4 2.2 0.27 3.22 0 4.1 245.5 0.16 7.3 1.2 0.33 4.22 1 4.4 257.9 0.14 8.3 2.0 0.24 2.5

High 0 0 5.2 28.8 0.21 14.3 1.4 0.43 3.50 1 5.7 26.9 0.16 14.5 2.1 0.33 1.71 0 5.8 124.4 0.21 15.4 1.5 0.46 2.81 1 5.7 118.4 0.16 15.3 1.9 0.36 1.42 0 5.7 205.9 0.17 17.5 1.6 0.38 1.62 1 5.7 190.3 0.20 16.5 2.2 0.41 2.0

(b) Analysis of variance summaries.

P values

Source df pH Bray-P K Ca Mg Mn Al

pH 1 0.011 0.582 0.440 0.217 0.598 0.078 0.386P 2 0.195 <0.001 0.590 <0.001 0.384 0.421 0.178D 1 0.002 0.960 0.005 0.371 0.006 <0.001 0.015P × D 2 0.523 0.886 0.561 0.045 0.360 0.681 0.399P × pH 2 0.085 0.494 0.644 0.477 0.555 0.642 0.904D × pH 1 0.730 0.479 0.196 0.202 0.139 0.680 0.363

Note: S, soil; P, phosphorus level; D, lime (dolomite) level.

Table 4. (a) Mean concentrations, and (b) analysis of variance summaries (P values) for Bray-P and exchangeableK, Ca, Mg, Mn, and Al in soil following completion of the experiment.



tations of alder may be desired. Our data suggest that earlygrowth of alder planted in soil previously supporting maturealder on such sites may be limited by P deficiencies. Thesefindings need to be confirmed by field experiments. Phos-

© 2003 NRC Canada

2094 Can. J. For. Res. Vol. 33, 2003

Sou

rce

NN

wp

Ncn

tP

Pw

pK

Ca

Mg

SF

eB

Cu

Zn

Mn

Al

Al w

p

pH0.

244

0.86

60.

956

0.05

20.

164

0.82

10.

831

0.87

30.

007

0.65

20.

260

0.03

90.

243

0.22

40.

126

0.48

0P

0.00

70.

013

<0.

001

0.00

4<

0.00

1<

0.00

10.

007

0.01

60.

115

0.02

20.

446

<0.

001

<0.

001

0.80

50.

478

0.02

5D

0.80

20.

654

0.30

20.

725

0.79

70.

479

0.78

00.

025

0.82

80.

391

0.04

40.

262

0.14

50.

325

0.25

30.

848

P×

D0.

482

0.73

90.

145

0.99

60.

949

0.45

60.

585

0.71

70.

773

0.12

70.

913

0.61

60.

189

0.65

50.

249

0.85

6P

×pH

0.63

80.

798

0.00

40.

496

0.58

90.

608

0.12

20.

156

0.18

50.

908

0.12

40.

075

0.00

70.

520

0.16

80.

914

D×

pH0.

127

0.03

00.

735

0.55

40.

745

0.67

70.

480

0.09

20.

432

0.34

30.

952

0.73

40.

981

0.50

00.

501

0.55

0P

×D

×pH

0.83

60.

560

0.75

30.

783

0.76

80.

966

0.46

10.

910

0.78

80.

341

0.29

90.

538

0.25

10.

737

0.99

60.

816

P×

S(p

H)

0.28

50.

744

0.50

60.

004

0.00

90.

018

0.00

40.

211

0.01

10.

661

0.05

10.

182

0.55

00.

002

0.16

80.

356

D×

S(p

H)

0.59

00.

790

0.84

40.

126

0.13

70.

003

0.08

10.

014

0.63

10.

236

0.54

70.

808

0.12

50.

002

0.01

00.

382

P×

D×

S(p

H)

0.33

20.

045

0.90

40.

023

0.00

40.

012

0.00

40.

121

0.06

90.

468

0.05

60.

016

0.37

30.

001

0.02

40.

341

Not

e:N

wp,

who

le-p

lant

Nco

ncen

trat

ion;

Ncn

t,w

hole

-pla

ntN

cont

ent;

P wp,

who

le-p

lant

Pco

ncen

trat

ion;

Al w

p,w

hole

-pla

ntA

lco

ncen

trat

ion.

Tab

le5.

Ana

lysi

sof

vari

ance

sum

mar

y(P

valu

es)

for

foli

aran

dse

lect

edw

hole

-pla

ntco

ncen

trat

ions

ofm

acro

-an

dm

icro

-ele

men

ts.

P0 P1 P2

Macronutrients (g·kg–1)N 32.1 34.2 34.5

Nwp 24.0 25.1 25.0

P 1.8 2.1 2.3

Pwp 1.8 2.2 2.5

K 9.1 6.7 6.1

Ca 1.0 1.2 1.3

Mg 0.3 0.4 0.4

S 2.4 2.6 2.7

Micronutrients (mg·kg–1)Fe 74 81 98

Cu 13 10 10

B 32 32 31

Zn 119 86 79

Mn 3619 3605 3403

Al 52 56 53

Alwp 1711 1299 1068

Note: Whole-plant concentrations are also shown for N(Nwp), P (Pwp), and Al (Alwp).

Table 6. Foliar elemental concentrations in relationto P addition rate.

Fig. 2. Relationship between relative growth rate (RGR) andwhole-plant P concentration (Pwp). The relation between RGRand Pwp was significantly improved for seedlings grown in theNitinat, Sarita, and Big Tree soils by excluding the seedlings re-ceiving dolomitic lime; those seedlings are not shown.



phorus deficiencies may not be a concern if P availability isrestored either by periodic flooding or following the harvestof an alder stand. Growth responses in bioassay studies suchas this are not constrained by competition from other veg-etation and optimal moisture supplies should allow fullexpression of potential growth responses to increased Pavailability. Conversely, the effects of P fertilization may begreater when moisture supplies are not optimal (Radwan andDeBell 1994) and processing of collected soil may increaseP availability. This, in turn, could lessen the response ofglasshouse-grown seedlings to added P. Consequently, theresponses to P additions observed in the glasshouse may notbe greater than those observed in more natural environ-ments.

Soils used in this study were from sites classified as veryrich, but P additions increased growth. On upland sites, thesoil fertility classification system employed in the studybetter predicted the availability of N than of other elements,including P (Kabzems and Klinka 1987). On alluvial sites,the likelihood of P deficiencies in black cottonwood, a com-mon associate of red alder, varied with bench height, andhence the frequency and duration of flooding (McLennan1996). Potential P deficiencies for alder on alluvial sitesmight therefore be more effectively predicted by a combina-tion of extractable P and bench height.

Acknowledgements

Sylvia L’Hirondelle and Cindy Prescott commented on thestudy plan, Chris Duncan and Petko Petkov assisted in soilcollection, and Keri Stockburger assisted in gas exchangemeasurements. Clive Dawson (Research Branch Laboratory)supervised nutrient analyses. Vera Sit and Peter Ott providedstatistical advice, and Jana Compton, Brian Titus, andAmanda Nemec reviewed earlier versions of the manuscript.Funding was provided by Forest Renewal BC.

References

Binkley, D., Cromack, K., Jr., and Baker, D.D. 1994. Nitrogen fix-ation by red alder: biology, rates, and controls. In The biologyand management of red alder. Edited by D.E. Hibbs,D.S. DeBell, and R.F. Tarrant. Oregon State University Press,Corvallis, Ore. pp. 57–72.

Bormann, B.T., Cromack, K., and Russell, W.O., III. 1994. Influ-ences of red alder on soils and long-term ecosystem productiv-ity. In The biology and management of red alder. Edited byD.E. Hibbs, D.S. DeBell, and R.F. Tarrant. Oregon State Univer-sity Press, Corvallis, Ore. pp. 47–56.

Brown, K.R. 1999. First-year growth responses of young red alderstands to fertilization. B.C. Minist. For. Ext. Note 36.

Brown, K.R. 2002. Effects of phosphorus additions on growth,mineral nutrition and gas exchange of red alder (Alnus rubra)seedlings grown in outdoor sandbeds. West. J. Appl. For. 17:209–215.

Cole, D.W., Compton, J., van Miegroet, H., and Homann, P.S.1990. Changes in soil properties and site productivity caused byred alder. Water Air Soil Pollut. 54: 231–246.

Compton, J.E., Cole, D.W., and Homann, P.S. 1997. Leaf elementconcentrations and soil properties in first- and second-rotationstands of red alder (Alnus rubra). Can. J. For. Res. 27: 662–666.

Courtin, P.J. 1992. The relationships between ecological site qual-ity and the site index and stem form of red alder in southwesternB.C. M.F. thesis, The University of British Columbia, Vancou-ver, B.C.

Freeden, A.L., Rao, I.M., and Terry, N. 1989. Influence of phos-phorus nutrition on growth and carbon partitioning in Glycinemax. Plant Physiol. 89: 225–230.

Giardina, C.P., Huffman, S., Binkley, D., and Caldwell, B. 1995.Alders increase phosphorus supply in a Douglas-fir plantation.Can. J. For. Res. 25: 1652–1657.

Green, R., and Klinka, K. 1994. A field guide for site identificationand interpretation for the Vancouver Forest Region. British Colum-bia Ministry of Forests, Victoria, B.C. Land Manage. Handb. 28.

Harrington, C., and Courtin, P.J. 1994. Evaluation of site qualityfor red alder. In The biology and management of red alder.Edited by D.E. Hibbs, D.S. DeBell, and R.F. Tarrant. OregonState University Press, Corvallis, Ore. pp. 141–158.

Hart, A.L. 1989. Distribution of phosphorus in nodulated whiteclover plants. J. Plant Nutr. 12: 159–171.

Hendershot, W.H., Lalande, H., and Duquette, M. 1993. Ion ex-change and exchangeable cations. In Soil sampling and methodsof analysis. Edited by M.R. Carter. Lewis Publishers, BocaRaton, Fla. pp. 167–176.

Hunt, R. 1990. Basic growth analysis. Plant growth analysis for be-ginners. Unwin Hyman, London.

Kabzems, R.D., and Klinka, K. 1987. Initial quantitative character-ization of soil nutrient regimes. I. Soil properties. Can. J. For.Res. 17: 1557–1564.

Kalra, Y.P., and Maynard, D.G. 1991. Methods manual for forestsoil and plant analysis. For. Can. Inf. Rep. NOR-X-319.

Klinka, K., Feller, M.C., Green, R.N., Meidinger, D.V., Pojar, J.,and Worrall, J. 1990. Ecological principles: applications. In Re-generating British Columbia’s forests. Edited by D.P. Lavender,R. Parish, C.M. Johnson, G. Montgomery, A. Vyse, R.A. Willis,and D. Winston. University of British Columbia Press, Vancou-ver, B.C. pp. 55–72.

Ljungstrom, M., and Nihlgard, B. 1995. Effects of lime and phos-phate additions on nutrient status and growth of beech (Fagussylvatica L.) seedlings. For. Ecol. Manage. 74: 133–148.

© 2003 NRC Canada


Fig. 3. Relationship among net photosynthetic rates (A), instanta-neous water use efficiency (A/E), and P treatment.



Marschner, H. 1995. Mineral nutrition of higher plants. 2nd ed.Academic Press, London.

Massie, M.R.C., Peterson, E.B., Peterson, N.M., and Enns, K.A.1994. An assessment of the strategic importance of the hard-wood resource in British Columbia. Forestry Canada and BritishColumbia Ministry of Forests, Victoria, B.C. For. Resour. Dev.Agree. Rep. 221.

McLennan, D.S. 1996. The nature of nutrient limitation in blackcottonwood stands in south coastal British Columbia. In Ecol-ogy and management of British Columbia hardwoods. Edited byP.G. Comeau, G.J. Harper, M.E. Blache, J.O. Boateng, andK.D. Thomas. Forestry Canada and British Columbia Ministryof Forests, Victoria, B.C. For. Resour. Dev. Agree. Rep. 255.pp. 89–111.

Milliken, G.A., and Johnson, D.E. 1992. Analysis of messy data.Vol. 1. Designed experiments. Van Nostrand Reinhold, New York.

Pezeshki, S.R., and Hinckley, T.M. 1988. The water relations char-acteristics of Alnus rubra and Populus trichocarpa: responses tofield drought. Can. J. For. Res. 18: 1159–1166.

Raaimakers, D., Boot, R.G.A., Dijkstra, P., Pot, S., and Pons, T.1995. Photosynthetic rates in relation to phosphorus content inpioneer versus climax tropical rainforest trees. Oecologia, 102:120–125.

Radwan, M.A., and DeBell, D.S. 1994. Fertilization and nutritionof red alder. In The biology and management of red alder.Edited by D.E. Hibbs, D.S. DeBell, and R.F. Tarrant. OregonState University Press, Corvallis, Ore. pp. 216–228.

Rodriguez, D., Keltjens, W.G., and Goudriaan, J. 1998. Plant leafarea expansion and assimilate production in wheat (Triticumaestivum L.) growing under low phosphorus conditions. PlantSoil, 200: 227–240.

Seiler, J.R., and McCormick, L.H. 1982. Effects of soil acidity andphosphorus on the growth and nodule development of black al-der. Can. J. For. Res. 12: 576–581.

Sprent, J. 1988. The ecology of the nitrogen cycle. Cambridge Uni-versity Press, Cambridge, U.K.

Thies, W.G., and Sturrock, R.N. 1995. Laminated root rot in NorthAmerica. USDA For. Serv. Res. Bull. PNW-GTR-349.

© 2003 NRC Canada

2096 Can. J. For. Res. Vol. 33, 2003



Documents

Effects of phosphorus fertilization and liming on growth, mineral nutrition, and gas exchange of Alnus rubra seedlings grown in soils from mature alluvial Alnus stands