摘要
在云南省境内的金沙江干旱河谷区 ,选择退化严重的草地群落研究氮磷施肥对群落动态的影响。经过一个生长季的施肥处理 ,结果表明 ,除大量施磷肥处理 ( 2 0g·a- 1 ·m- 2 )时 ,可能因施磷过多群落生物量和密度没有出现增加外。其余的施氮和施磷处理均导致群落地上生物量和密度增加 ,而且施氮处理引起群落地上生物量和密度增加的程度都高于施磷处理。说明在干旱河谷退化严重的草地生态系统 ,氮是限制系统恢复的主要因素。施肥后禾本科草本植物密度大量增加 ,而乔灌木密度增加不明显 ,群落在短期内变成以禾本科草本植物为主的状态。施氮和施磷没有引起群落种数量和植物多样性指数的明显变化。试验结束时土壤的铵态氮、硝态氮和有效磷浓度没因施肥而增加 。
At the dry valley along Jingsha River, a highly degraded grass community was selected to determine the effect of N、P fertilization on community dynamics. After one growing season of N and P application, the results showed that the above ground biomass and species density increased except the one with the highest P (20 g·a -1·m -2) treatment,and the increases caused by N applications were greater than that of P applications, therefore N was the limiting factors for the restoration of community. After the treatment, the density of Gramineae species increased sharply, but that of tree and shrub species did not increase significantly, so we can conclude that the community has become Gramineae dominant within the short term. Both N and P treatment did not caused significant changes in species type and diversity. Up to the end of treatment, NH 4 +、NO 3 - and available P in the soil did not increase with the application of N、P, but the content of N and P in the biomass increased。
出处
《植物研究》
CAS
CSCD
北大核心
2004年第1期59-64,共6页
Bulletin of Botanical Research
基金
中国科学院特别支持项目 :册地灾害--泥石流
滑坡防治研究
