水保所知识产出(1956---)知识库

为阐明黄土丘陵区不同草本群落生物量与土壤水分的相关特征，通过野外调查与定点观测，对延河流域内不
同演替阶段的5 种草本植被( 长芒草、铁杆蒿、茭蒿、白羊草、大针茅) 群落地上生物量、土壤水分特征及其相关关系
进行研究与分析。结果表明: 在0 ～ 500 cm 土层内，各演替阶段草本群落土壤含水量的垂直分布规律明显，均表现
为浅层( 0 ～ 50 cm) 减少、中层( 50 ～ 200 cm) 增加、深层( 200 ～ 500 cm) 基本稳定的趋势; 植物群落地上生物量均随
着演替年限呈先增加后减小趋势，在白羊草群落阶段( 退耕演替25 a 左右) 达到最大值; 草本群落地上生物量与土
壤含水量整体呈正相关关系，相关程度以0 ～ 200 cm 土层较高; 植被群落利用土壤水分土层深度随群落演替阶段逐
渐加深，表现出对环境更强的适应性。

The objective of this study is to elucidate the biomass production and soil moisture
characteristics of different herb communities at different succession stages in the Loess Hilly-gully Ｒegion
on the Loess Plateau． After filed investigation and in situ observation，the aboveground biomass，soil
moisture and their relationships of five different herbaceous communities ( Stipa bungeana，Artemisia
sacrorum，A． giraldii，Bothriochloa ischaemum，S． grandis) in Yanhe Watershed were analyzed． Ｒesults
showed that: soil moisture contents of the five plant communities at different succession stages had
obvious vertical distribution characteristics in 0 － 500 cm soil profile，which decreased in 0 － 50 cm layer，
then increased in 50 － 200 cm layer，and maintained stable in 200 － 500 cm layer; aboveground biomass
of plant communities showed an increase at early succession stages，reaching the peak at B． ischaemum
stage ( about 25 years after returning farmland ) ，and decreased thereafter; there existed positive
correlations between aboveground biomass and soil moisture，especially for that in 0 － 200 cm soil layer;plant communities can make use of soil moisture in deeper layers over succession，showing a strong
adaptation to environment．