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[1]吴宁,罗鹏.长江上游高寒草地生态建设和管理中生态理论的若干质疑[J].应用与环境生物学报,2004,10(04):537-542.
 WU Ning,et al..Rethinking on the ecological theories related to the ecological construction and management of the highfrigid grasslands in the upper Yangtze River[J].Chinese Journal of Applied & Environmental Biology,2004,10(04):537-542.
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长江上游高寒草地生态建设和管理中生态理论的若干质疑()
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《应用与环境生物学报》[ISSN:1006-687X/CN:51-1482/Q]

卷:
10卷
期数:
2004年04期
页码:
537-542
栏目:
综述
出版日期:
2004-08-25

文章信息/Info

Title:
Rethinking on the ecological theories related to the ecological construction and management of the highfrigid grasslands in the upper Yangtze River
作者:
吴宁罗鹏
Author(s):
WU Ninget al.
(Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu610041, China)
关键词:
关键词 长江上游 草地 承载力 非平衡 游牧型畜牧业
Keywords:
Keywords Carrying capacity nomadic pastoralism nonequilibrium rangeland management Upper Reaches of the Yangtze River
摘要:
摘要现有的草地管理政策和措施建立在西方经典生态学理论的基础上,并在很大程度上改变了传统管理模式.本文针对长江上游高寒草地生态建设与管理中的问题,结合草地生态学的新进展,从草地生态系统特征、多样性与稳定性、草地承载力、平衡与非平衡等几个方面进行了讨论,旨在能引起今后草地生态建设中加强这些方面的针对性研究,并有效地避免由于理论自身偏差而导致不应有的技术失误.本文的中心观点在于,由于长江上游地区的高寒草地处在环境因子剧烈变化的条件之下,草地的生态过程在很大程度上受制于非生物条件(如气候),而不是生物因子的相互作用(如放牧),因此,已有的一些草地生态理论不能完全解释草地动态变化的机理,其适用性受到限制,而任何简单套用理论以及基于这些理论发展的技术和模式都有可能给生态治理和管理带来负面影响. 图2 参22
Abstract:
Abstract Current approaches aiming to promote "scientific" rangeland management in the Upper Reaches of the Yangtze River have greatly impacted the traditional nomadic pastoralism which local communities have practised for thousands of years. On the basis of some new research findings, the authors argue that some of the current approaches may be misguided and further researches on ecological theories are urgently in need, especially in the aspects of the interrelationships between ecological diversity and stability, the carrying capacity and the nonequilibrium characteristics of the highaltitude rangelands. As in many parts of the world, the rangeland environment in the upper reaches of the Yangtze River is under threat. Since the beginning of 1990s a lot of attentions have been paid to ecological degradation in this region, and the ecological restoration of degraded forest and grassland ecosystems has become the key task for the future sustainable development in this immense and underpopulated land with the implementation of the great strategy of western China development. In this context, scientists or technicians must think over some basic questions involving in practices. At first, has over few decades investment in range science helped to mitigate problems of degradation, management and development? Are rangeland pastoral systems so complex that the degree to which they can be understood and managed is inherently low? These questions are particularly relevant as we enter a period when the global environment is undergoing unprecedented and rapid change as a result of human activity. Finally, how well does our theoretical base about ecological restoration equip us to anticipate the impacts of changing climate and land surface conditions? In this paper, the authors have an attempt to examine the degree to which western ecological theory in particular has assisted in rangeland management, and to understand the circumstances where it is effective and ineffective. With a few examples from western Sichuan, the authors debated on some ecological theories related to rangeland management and pastoral development, which formed bases for our past scientific practices. In fact there is no welldesigned experiment so far, with identical replicates randomly assigned to a with theory treatment and a without theory control, which shows more effective under with theory treatment. Meanwhile, it was found that traditional pastoralists have their own richintheory constructs. Many traditional ideas make sense from a western perspective, thus indicating a degree of common ground. Because of the differences in output objectives, it can not be sure that the secondary productivity if it is measured in energetic terms (thus including draught power and milk) rather than animal offtake alone is higher in the reformed pastoral system than the traditional one. In the past century many of the rangeland ecology researches revolved around the fundamental questions: (1) how many animals should there be on a given piece of land; and (2) when and where should they be moved within the land. However, none of these questions is even close to being fully resolved, which in itself is a statement about the weakness of any claims that they might have for a positive influence on rangeland outcomes. Therefore, there is a theoretical divergence over what the maximum sustainable stocking rate is and the degree to which it is a fixed or variable system property. The concepts of carrying capacity are discussed in this paper and the concepts are shown to have generally failed in highlyvariable environments (e.g. the Tibetan Plateau with the characteristics of nonequilibrium) and where there are mixed objectives (e.g. Tibetan nomadic pastoralism), although they have been successfully applied in systems which are homogeneous in their objectives and have low interannual variability in plant production. For this issue the debate is over whether in highly variable environments the theoretical instantaneous or timeand space averaged maximum carrying capacity has any practical significance, since the animal management and social parts of the pastoral system are unable to track the variations as rapidly as they occur, and is thus seldom actually at this value. As for other causes of ecological degradation, regulation of stocking rate on a patch of rangeland is considered as mixed socio economic/biophysical questions, which cannot be solved by ecological theory alone. Indeed a case can be made that the inappropriate application of inadequately validated theory may have contributed to rangeland degradation in some places. In this paper, the authors argue that western ecological theory has made a limited contribution to the success of highaltitude rangeland systems in the upper Yangtze River and even in the western China. The focused point of this paper is that, in the situation where the environment fluctuates greatly, physical conditions (like climate) rather than biological factors (like livestock grazing) are the key force in modulation of the rangeland ecosystem processes. As classical theories can explain only parts of the known dynamic processes of the rangelands, their applicability is limited. Furthermore, any management practice that is built indiscriminately on these classical theories may be detrimental to the ecological sustainability of the rangelands. Fig 2, Ref 22
更新日期/Last Update: 2004-08-24