长期连续种植苜蓿草地地上部分生物量与土壤水分的空间差异性  

Spatial variability of soil moisture and aboveground biomass of Medicago sativa under long term continuous planting

作　　者：王俊[1,2] 刘文兆[1] 钟良平[1] 李玉山[1] 

机构地区：[1]中国科学院水利部水土保持研究所,陕西杨凌712100 [2]西北大学城市与资源学系,陕西西安710127

出　　处：《草业学报》2009年第4期41-46,共6页Acta Prataculturae Sinica

基　　金：中国科学院知识创新工程重要方向项目(kzcx2-yw-424);国家自然科学基金项目(30500077)资助

摘　　要：基于苜蓿长期连续种植定位试验,研究了不同施肥与采样位置差异对苜蓿草地地上部分生物量和土壤水分的影响。苜蓿长期连续种植19年后,施肥对苜蓿地上部分生物量的影响不显著;试验样地内呈由外及内植株高度逐渐下降、地上部分生物量积累逐渐减小的"生物漏斗"现象,距样地中心位置不同引起的差异远远超过施肥处理引起的差异。中下层土壤水分也呈类似的漏斗状分布。相关分析表明,苜蓿地上部分生物量与1 m以下土壤水分含量呈显著相关,表明在长期连续种植条件下下层土壤水分状况是决定苜蓿草地生长状况的主要因素。Impacts of fertilization and sampling position on soil moisture and aboveground biomass of Medicago sativa were studied in a long term, in situ experiment. After 19 years continuous M. sativa planting, fertilization had no impact on M. sativa aboveground biomass. However, plant height declined and accumulation of aboveground biomass decreased towards the center of the experimental plot, like a biomass funnel. Differences due to sampling position were much bigger than those due to fertilization. Soil moisture in the layers below 1 m also resembled a moisture funnel and significantly correlated with M. sativa aboveground biomass, which indicated that subsoil moisture may be crucial to M. sativa growth in long term continuous plantings.

关 键 词：苜蓿 生物漏斗 水分漏斗 长期试验 

分 类 号：S541.9[农业科学—作物学] S812