摘要
通过野外控制实验,研究了高寒矮嵩草草甸群落植物多样性、初级生产力对模拟降雨条件的响应.结果表明: 1 在植物生长期 6月 ,增加降雨20%、增加降雨40%,植物群落物种多样性指数 H 和均匀度指数 J 分别比对照提高了0.188和0.011、0.735和0.076,生长期 7月 增加降雨20%物种H和J提高了0.409和0.07; 2 禾草类:增加降雨20%处理的地上生物量与对照相比没有明显的显著性差异 P>0.05 ,增加降雨40%处理的地上生物量与对照相比差异显著 P<0.05 ,说明过多增加降雨会抑制禾草的生长发育.杂类草:减少降雨50%处理的地上生物量与对照相比差异显著 P<0.05 ,其地上生物量对减少降雨的反映比较敏感.莎草类:其地上生物量对增加和减少降雨都没有显著变化; 3 0～10cm和0～30cm土层地下生物量均在增加降雨20%时最高,地下生物量的总量也在增加降雨20%时最高; 4 矮嵩草草甸地下生物量与地上生物量、总生物量的比值接近于生长季末时最大,且在模拟增加降雨20%的水平时,7、8、9月份地下和地上生物量较其它处理组高.
Field controlled experment was used to examine response of biodiversity and productivity to simulated rainfall changes in an alpine Kobresia humilis meadow.The results indicated that 1) The diversity index (H) and evenness index (J) of plant community increased by 0.188 and 0.011?0.735 and 0.076 respectively over the control plot in the 20% and 40% rainfall supply increased plots in the growing season of plants (June),The diversity index (H) and evenness index (J) of plant community increased by 0.409 and 0.07 over the control plot in the 20% rainfall supply increased plot in the growing season of plants (July).2) Grasses:There is no significantly different (P>0.05) between 20% rainfall supply increased plots and control plot of belowground biomasses,significantly different (P<0.05) between 20% rainfall supply increased plots and control plot of aboveground biomasses,from this we can say that excessive precipitation would restrain growth of grasses.Forbs:50% rainfall supply decreased plots and control plots of aboveground biomasses show significantly different (P<0.05),response of abovebiomasses to rainfall supply decreased is sensitive.Sedges:no significantly different of Sedges biomass to rainfall supply increased or decreased.3) The belowground biomass of 0~10 cm?0~30 cm soil layer and total biomass were higher at 20% simulated rainfall supply increased.The proportion of belowground biomass and aboveground biomass was higher the ending growing season as well as total biomass,belowground biomass and aboveground biomass were higher than other treatment plots at 20% simulated rainfall supply in July?August?September.
出处
《西北植物学报》
CAS
CSCD
2003年第10期1713-1718,共6页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家重点基础研究发展规划项目 (G1998040814)
中国科学院知识创新工程项目 (KSCX2-1-07)
国家"十五" 科技攻关计划项目
中国科学院海北站基金项目
关键词
模拟降水
矮嵩草草甸
植物多样性
初级生产力
simulated rainfall
alpine Kobresia humilis meadow
biodiversity
productivity
