EFFECT OF CLAY CONTENT AND AGGREGATE SIZE ON AVAILABILITY OF SOIL WATER TO TOMATO PLANTS
[摘要] WateravailabilityinSt.Bernardsandyclayloam,ChateauguaysiltyclayloamandSte.Rosalieclaysoilswasdetermined.Thecriterionofwateravailabilitywasgrowthrate,measuredasanincreaseinleafareaasafractionofexistingleafarea,oftomatoplantsgrowninacontrolledenvironmentroom.Atagivensoilsuction,growthratewashigherinthetwosoilshighinclaycontentthaninthemediumtexturedSt.Bernard,andwasdependentuponaggregatesize.Differencesinhydraulicconductivityandwaterretentionpropertiesaccountedformostbutnotallthedifferencesingrowthrate–soilsuctionrelationships.Inthetwosoilsofhigherclaycontent,growth–soilsuctionrelationshipsofundisturbedsoilswerenotmateriallydifferentfromthoseinsievedaggregates.Oxygendiffusionratesatleastaslowas10 × 10−8 gcm−2min−1overshortperiodswereadequateformaximumgrowthanddidnotappeartoinfluenceavailabilityofwater.
[发布日期] [发布机构]
[效力级别] [学科分类] 农业科学（综合）
[关键词] [时效性]
