地理科学进展 ›› 2007, Vol. 26 ›› Issue (6): 33-43.doi: 10.11820/dlkxjz.2007.06.004

• 生态与环境 • 上一篇    下一篇

植被作用下土壤干化的反馈效应 及相关问题讨论

王晗生   

  1. 1. 西北农林科技大学, 杨凌712100|2. 中国科学院、水利部水土保持研究所, 杨凌712100
  • 收稿日期:2007-04-01 修回日期:2007-09-01 出版日期:2007-11-25 发布日期:2007-11-25
  • 作者简介:王晗生( 1965-)| 男, 甘肃武威市人, 博士, 副研究员, 主要从事旱区植被建设及生态学研究. E-mail:hswang@ms.iswc.ac.cn
  • 基金资助:

    国家科技支撑计划课题( 2006BAD09B09) ; 中国科学院水土保持研究所知识创新领域前沿项目.

Discussion on Feedback Effect of Soil Desiccation by Vegetation and Related Issues

WANG Hansheng   

  1. 1. Northwest A&F University, Yangling 712100, China|2. Institute of Soil and Water Conversation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China
  • Received:2007-04-01 Revised:2007-09-01 Online:2007-11-25 Published:2007-11-25

摘要:

黄土高原普遍发生的植被作用下的土壤干化现象, 从一个独特角度恰当反映了环境对植 被的限制作用。由于人工林草植被不同于天然植被, 其负反馈调节机制脆弱, 这种植物生长用水 与环境供水之间的矛盾表现, 使人工林草植被生长滞缓, 稳定性下降, 甚至导致其衰亡, 并对后续 深根性植物的生长发育一般起到显著的抑制作用。但是, 后续天然植被或者浅根性植物却仍然能 够继续良好发育。显然, 植被作用下的土壤干化, 对追求一定的经济目标来说有其不利性, 但对于 防止土壤侵蚀并不一定就产生负面影响。需要根据经营目标区别对待人工林草植被的稳定性。人 工林草植被的自然化过程研究是有关生态恢复的一个有意义的命题。

关键词: 反馈效应, 黄土高原, 土壤干化, 植被建设

Abstract:

Owing to vegetation construction in the Loess Plateau, much attention has been paid to soil desiccation by vegetation for many years. Right thinking about soil desiccation by vegetation would conduce to controlling it, and furthering reasonable management and evolution of vegetation. The feedback response of vegetation to soil desiccation by itself is mainly discussed in this paper. We believe that the phenomenon of soil desiccation by vegetation occurring universally in the Loess Plateau just reflects environmental limitation on vegetation from a peculiar angle. Because artificial forest and grass vegetation is weak in the mechanism of negative feedback regulation compared with natural vegetation, the contradictory show between water use by plant growth and water supply by environment constitutes a so serious threat to stability of artificial forest and grass vegetation that it grows slowly and even declines, and commonly takes marked restraining effect on development of follow- up plant rooting deep after vegetation declination. But on the other hand it is noticeable that follow- up natural vegetation or plant rooting superficially still may succeed to grow well. It is obvious that soil desiccation by vegetation isn ’t favorable for seeking economical goal, but it would uncertainly cause a negative effect on protection of soil from erosion. The stability of artificial forest and grass vegetation should be treated respectively according to their managing goals. The research on naturalizing process of artificial forest and grass vegetation would be a significant proposition related to ecological restoration.

Key words: feedback effect, Loess Plateau, soil desiccation, vegetation construction