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晋西黄土区集雨补灌果园耗水特征及补灌效应研究

Study on Characteristics of Water Consumption of Orchard and Supplementary Irrigation Effect on Loess Plateau of Shanxi Province

【作者】 郭小平

【导师】 周心澄;

【作者基本信息】 北京林业大学 , 水土保持与荒漠化防治, 2006, 博士

【摘要】 坡地旱作果园是我国黄土区坡面主要农林业经营形式。对不同补灌条件下果园水分的分配、运行和消耗与果树营养、生殖生长反应进行系统研究,是了解果园蒸散耗水特征、水分生产效率、果园补灌土壤水分低限,选择适宜补灌临界需水期、补灌定额和最优补灌技术模式等的基础,具有重要的理论意义和实践价值。试验以山西吉县蔡家川试验林场旱地富士苹果、酥梨为研究对象,采用正交设计、对比定位观测法,对生长季不同补灌苹果梨园雨水资源、土壤水分、蒸腾、蒸散耗水特征以及果树生长反应进行研究,同时采用盆栽控制试验,对不同水分梯度与果树蒸腾耗水及水分生理指标关系进行研究,并运用非充分灌溉理论,探讨了旱作集水补灌果园适宜的补灌时期、补灌定额及优化技术模式。研究结果表明:●研究地区年际降水变化较大,降水相对变率为18.1%,年降水主要集中在夏秋季节,约占年降水量的78.4%;春季(3-5月)的降水量仅占全年降水量的18.0%。降水量是影响当地果树产量的主要气象因子,萌芽期、幼果生长期、果实迅速膨大期的降水量对苹果和梨生长以及最终产量影响最大。●虽然补水对果园旱情有所缓解,但年际降水量、年降水总量和年内降水分布仍然制约着果园土壤水分动态和垂直变化。春夏强烈失墒期(4月上旬~6月下旬)、阶段末果园土壤水分含量达到最低值为6%~8%,补充灌溉可以缓解该阶段的土壤水分亏缺。雨季水分补偿期(7月上旬~9月中旬),一般不需补灌。●年际降雨、年内降水总量、降水量季节分布、灌溉水量及灌水时期制约着果树实际耗水的消长。干旱年苹果、梨周年耗水过程呈单峰型,而平水年雨季推迟,则苹果、梨周年耗水过程呈双峰型,6月下旬~7月上旬耗水强度最大,属于生长季果树最大需水期,5月上旬~6月下旬是果树需水临界期,3月下旬~5月上旬属于苹果、梨水分敏感期,此时通常发生轻度或中度水分胁迫。●补灌果园苹果和梨正常生长适宜的土壤(碳酸盐褐土)水分低限范围分别为11%一14%和10%一15%,土壤水合补偿点分别为4.31%和4.14%。当生长季果园水分敏感期(萌芽开花期)和临界需水期(幼果膨大期)土壤含水量低于以上低限范围时应补灌,成龄富士苹果和酥梨灌溉的定额分别为101~203m~3/hm~2和68~135m~3/hm~2,一般补灌2次。●随着补水量的增加,果树的生长发育如新梢生长,果实产量都有明显增加,补水量大,产量增加越明显。但果树蒸散、蒸腾水分生产效率在高定额补灌量下反而下降,而在低定额补水条件下,富士苹果和酥梨单株水分生产力

【Abstract】 Slope orchard in arid area is the main forestry manage model on Loess Plateau.Study on the distribution,transportion and consumption of water and nutrient and degenerated growth of fruit tree,which is the basis for the characteristics of evapotranspiration,produc- tivity efficient with water,the lowest soil water content,choosing suitable critical water requirement period ,supplementary irrigation quality and optional technique model for supplementary irrigation that have the important theory significance and practice value.Studying on the Fushi apple and pear tree in Chaijiachuan forest farm in Jixian country, Shanxi province ,with the orthogonal design and experiment for observation,research on the precipitation resource,soil water content , transpiration, evapotranspiration and fruit tree growth in the orchard of apple and pear tree in different growth season,at the same time, under the potted experiment,the paper analysed the relation between different soil water content with transpiration and physiological index.With the theory of limited irrigation,the paper also researched suitable supplementary irrigation period,quality and optional technique model for supplementary irrigation orchard in arid area.The results indicated:●Relative changing rate of precipitation is 18.1%,annual precipitation is concentrated in the summer and autumn,which is the 78.4 percent of the annual precipitation; the precipitation in spring (March to May) when the fruit tree is on the time for budding and blossom, is only 18.0 percent of the whole year, which influenced growth and yield in a long time.The budding period, young fruit growing period and fruit growing rapidly period are the periods that sensitive to water and critical water requirement period to the growth of apple and pear tree, which influenced final yield.●Although the supplementary irrigation relaxed the drought of the orchard,the precipitation in different years,the whole precipitation in the whole year and distribution of

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