不同密度樟子松固沙林土壤水分特征  

Soil Moisture Characteristics of Sand Fixation Forest of Pinus Sylvestris var.Mongolica with Different Plantation Densities

作　　者：冯伟[1] 杨文斌[1] 党宏忠[1] 李卫[1] 韩辉[2] 宋晓东[2] 张学利[2] 

机构地区：[1]中国林业科学研究院荒漠化研究所,北京100091 [2]辽宁省固沙造林研究所,辽宁阜新123000

出　　处：《水土保持通报》2015年第5期189-194,共6页Bulletin of Soil and Water Conservation

基　　金：国家重点基础研究发展计划"沙区土壤水分时空分布格局与区域分异规律"(2013CB429901);国家自然科学基金项目"半干旱区低覆盖度固沙林的水分动态及其应对极旱年的调节机理"(31170667)

摘　　要：[目的]探讨樟子松固沙林合理栽植密度,为进一步深入分析樟子松固沙林水量动态平衡、衰退原因及林分稳定性评价提供参考。[方法]以科尔沁沙地南缘3种密度(400,600和800株/hm2)的33a樟子松固沙林为研究对象,连续监测了生长季降雨、0—200cm土壤含水量、200cm以下渗漏量,分析了3种密度下土壤水分特征及差异。[结果](1)3种密度下土壤水分时空变化趋势基本一致,0—30cm为降雨影响剧烈层,60cm以下受>40mm降雨影响,降雨结束后均表现蒸渗型水分消退特征,之后转换为蒸散型;(2)0—200cm土壤体积含水量大小为:400株/hm2>600株/hm2>800株/hm2,且差异显著(p<0.05);(3)200cm以下均有水分渗漏,其中800株/hm2最低,为0.4mm。[结论]丰水年3种密度林分基本能够维持水量平衡,但正常降水或极端降水年份会增加土壤蓄存水消耗,可能出现水分亏缺或衰退现象。建议生产中樟子松固沙林适宜密度应控制在400株/hm2左右。[Objective]To investigate the optimal density of Mongolian pine（Pinus sylvestris var.mongolica）plantation for sand fixation in order to provide reference for the analysis of dynamic water balance,decline causes and stand stability evaluation in the study area.[Methods]We took the Mongolia pine filed in the southern edge of Horqin sandy land,Zhanggutai,Liaoning Province as a case study to monitor soil moisture variation（0—200cm）,rainfall in growing season and leakage below 200 cm.The surveys were conducted in three different Mongolia pine fields with various plantation densities（400plants/hm2,600plants/hm2 and800plants/hm2）.[Results]The temporal and spatial variation trends of soil moisture in all the three plantation densities were consistent.Soil layer at 0—30cm was influenced by rainfall dramatically,while soil layer at 60—200cm was only influenced by rainfall〈40mm.Soil moisture regression processes dissipated from lysimeter type to evaporation-leakage type after rainfall.Soil moisture showed significant differences among three plantation densities（p〈0.05）in topsoil（0—200cm）：400plants/hm2 〉600plants/hm2 〉800plants/hm2.Water leakage was observed in all three plantation densities below 200 cm.The 800plants/hm2 field had the least leakage.[Conclusion]In wet years,water balance can be maintained in all three densities,while water deficit and recession may occur in normal year and years with extreme precipitation.The optimal planting density of Mongolian pine is around 400plants/hm2 in the sandy land.

关 键 词：樟子松 土壤体积含水量 水分渗漏量 

分 类 号：S791.253[农业科学—林木遗传育种] S152.7[农业科学—林学]