【作者】 刘兴元；

【导师】 龙瑞军；

【作者基本信息】 兰州大学 ， 草业科学， 2011， 博士

【摘要】 藏北高寒草地是我国重要的畜牧业生产基地和生态安全屏障。然而,高寒草地退化使藏北高原陷入了生态环境恶化、经济发展滞后和牧民生活贫困的窘境,由此引发了一系列的生态、经济、环境和社会问题,不仅严重影响藏北高原畜牧业生产和牧民生活,而且直接威胁到区域生态安全和东亚水资源安全。为了遏制草地退化趋势,维护草地的生态服务功能,提高草地生产能力,协调人口、资源、环境和经济发展的关系,实现生态、经济和社会的可持续发展,需要将自然科学问题与社会经济发展政策紧密结合起来,评估高寒草地生态系统服务功能价值,建立有效的草地生态补偿机制,对制定合理的生态屏障保护与畜牧业经济发展策略具有重要意义。本研究基于生态经济学原理和可持续发展理论,以藏北那曲地区为例,采用定量与定性相结合的方法,分析藏北高寒草地生态系统现状与发展态势,以及生态屏障保护与经济发展之间不同利益主体为了各自利益诉求进行博弈的均衡关系,定量评估了高寒草地生态系统的可持续发展水平。针对高寒草地生态系统的特点以及造成退化的自然和社会经济驱动因素,阐明了高寒草地生态系统生态、生产和生活功能(“三生功能”)的互作机制。建立了基于“三生功能”的高寒草地生态系统服务功能评估体系和方法,定量评估了不同类型与不同退化程度草地的生态服务价值及其损益水平,揭示了不同退化程度草地放牧获取经济价值与草地退化损耗生态服务价值的关系,构建了基于草地功能分区的分区分级生态补偿机制,提出了藏北高寒草地生态系统可持续发展的对策,取得以下主要结论：1)生态屏障保护与经济发展之间的博弈失衡是高寒草地退化的主要外部驱动力,目前,藏北那曲地区的高寒草地生态系统处于不可持续发展状态。通过分析藏北高寒草地生态系统现状及发展态势,阐明了中央政府、地方政府和牧民在生态屏障保护与经济发展之间的博弈失衡是导致高寒草地退化,生态服务功能下降的主要外部驱动因素。利用复合生态系统场论分析方法,构建了以“三生功能”为基础的草地生态系统可持续发展评价体系和计算模型,对藏北那曲高寒草地生态系统的可持续发展度进行了定量评价,结果表明藏北那曲高寒草地生态系统的发展位已达到或超过了系统的最大承载能力,发展势缺乏潜能,协调性较差,可持续发展度很低,目前处于不可持续发展状态。2)在人口压力和放牧压力与资源环境承载力之间的相互作用下,高寒草地生态系统“三生功能”的互作机制表现为非线性的多元耦合、多维连锁和多重反馈的内在关系。当高寒草地生态系统的人口压力和放牧压力低于其环境承载力时,系统处于平衡或健康状态,反之,人口压力和放牧压力与环境承载力关系失衡,造成高寒草地生态系统功能紊乱,导致高寒草地退化,最终使系统处于不可持续的发展状态。因此,通过分析人口压力和放牧压力与资源与环境承载力之间的相互作用,阐明了高寒草地生态系统生态、生产和生活功能的互作机制,其表现为非线性的多元耦合、多维连锁和多重反馈的内在关系。通过明晰“三生功能”结构变化对生态系统服务功能的影响,提出了草地生态服务功能当量的概念,以此确定了“三生功能”量比关系。在这一基础上,以国家公布的2008年农牧民脱贫线和小康线标准,估算了藏北那曲地区牧民在这2个标准下,高寒草地生态系统的人口承载量。根据高寒草地健康状况估算,草地退化与未退化的人口承载量相比,脱贫线和小康标线均下降了60%；根据2008年那曲地区的牧业GDP估算,实际牧业人口占了脱贫线的96.3%,但与小康线相比,超载了489.2%；以2008年那曲地区实际牧业人口与草地未退化状态时估算人口承载量相比,实际人口分别占了脱贫和小康线的14.2%和85.9%,但与草地退化的估算人口承载量相比,实际牧业人口占脱贫线的36%,但小康线超载了118.9%。3)构建了草地生态服务价值评价体系和方法,对藏北那曲地区高寒草地生态系统服务价值评估结果为1199.07亿元／年,草地退化造成的生态服务价值损失达586.27亿元／年。综合考虑了高寒草地的地域差异性、空间异质性和区域经济发展水平差异性,选择贡献率较高的12项指标,构建了草地生态系统服务价值评估体系和方法,并对藏北那曲不同类型和退化程度高寒草地的生态服务价值及其损失进行了评估。表明藏北那曲地区高寒草地生态系统的年总生态服务价值是1199.07亿元。其中,高寒草原、高寒荒漠、高寒荒漠草原和高寒草甸提供的生态服务价值分别占总生态服务价值的62.9%、1.5%、8%和28.1%。从退化程度上看,未退化、轻度退化、中度退化和严重退化草地提供的生态服务价值分别占总生态服务价值的54.9%,29.3%,11%和4.8%。通过对2008年藏北那曲高寒草地生态服务价值损益评估表明,高寒草地退化造成的生态服务价值损失达586.27亿元/年,平均损失率32.8%。而高寒草地在未退化状态时可产出的总经济价值为22.94亿元/年,年损失生态服务价值相当于总经济价值的25.6倍,即超载放牧1个羊单位损失的生态服务价值是其获取经济价值的13.9倍。显然,高寒草地生态屏障保护产生的生态服务价值远大于超载放牧获取的经济价值。4)提出了基于高寒草地功能分区的分级生态补偿机制,设计了针对不同功能区的生态补偿方案。依据高寒草地的生产力、季节放牧重要性、生态服务价值、生态环境敏感性指标,构建了高寒草地功能分区模型,并从空间上将藏北那曲地区高寒草地划分为适度生产功能区、减畜恢复功能区和禁牧封育功能区。3个功能区的面积分别占藏北那曲地区总草地面积的24%、50%和26%。提出了基于高寒草地功能分区的分区分级生态补偿机制,设计了针对不同功能区特点的生态补偿方案和约束奖惩机制。核算出那曲地区的生态补偿周期为5年时,共需补偿资金35.77亿元,年需7.16亿元,其中,适度生产功能区、减畜恢复功能区和禁牧封育保护功能区分别需要补偿资金19.4亿元、15.77亿元和0.6亿元。5)构建了藏北高寒草地生态系统可持续发展的战略框架,提出了藏北那曲高寒草地生态系统可持续发展的对策。在政府主导,牧民参与基础上,由制度、政策、项目、资金、技术和管理等要素,构建高寒草地生态系统可持续发展的战略框架,建立环境成本核算体系和草地动态监测评估体系,实施生态补偿政策,完善草地管理的法律法规,明确高寒草地生态系统在生态屏障安全和区域经济发展中主导动能,实行生态移民工程,发展生态畜牧业。从制度建设,观念转变,模式创新,技术集成等方面,提出了藏北高寒草地生态系统恢复与重建的可持续发展对策。更多还原

【Abstract】 Alpine rangeland in the Northern Tibetan region of China is not only a material base for livestock production, but also plays important role in the ecological safety shelter zone for China, even southeast Asia region. However, the alpine rangeland degradation of local region caused the ecological deterioration, low economic development, and poor living of herders, resulting in dilemma of sustainable development of the northern Tibetan region. Thus alpine rangeland degradation not only threatens the local ecological safety and life of the local residents, but also threatens further ecological security of the down-streams of the rivers and the Southeast Asia Rivers. Therefore, on the basis of closely combining the problems in natural science and economical development policy in social science, evaluating ecological services value of rangeland and establishing effective compensation mechanism of rangeland are urgent to maintain ecological services function of rangeland and coordinate the relationships among population, resource environment and economic development, which will provide useful information for protecting rangelands from the further degradation and achieving sustainable development of ecological, economic and social.As a case of the Naqu region in northern Tibet, firstly, this study analyzed the current situation of alpine rangelands ecosystem and the game relationship between protection of ecological safety shelter zone and development of animal husbandry economy; secondly, this study evaluated sustainable development degree and disclosed interaction mechanism among ecological function, productive function and livelihood function (EPLF); thirdly, this study established the evaluation system and proposed methods of ecological services value of rangeland ecosystem based on EPLF, and used this established evaluation system and methods to evaluate the ecological services value of different rangeland type and loss value of different degradation degree rangeland, and then analyzed the relationship between economic value resulting from grazing and loss value of ecological services value caused by alpine rangeland degradation; fourthly, Mechanism of ecological compensation for alpine rangeland was designed based on the function subarea and grading of alpine rangeland and proposed the plan of ecological compensation; finally, this study presented the countermeasure of sustainable development of alpine rangelands. The main results in this study are as following.First, the out-of-balance gaming between ecological safety shelter zone and animal husbandry economy was the main external driver of alpine rangeland degradation, and alpine rangelands ecosystem in the Naqu region of northern Tibet was unsustainable development situation.After analyzing the current situation of the alpine rangelands ecosystem in the Naqu region, northern Tibet, this study found that the out-of-balance gaming between ecological safety shelter zone and development of local animal husbandry economy among central government, local government and herdsman caused the degradation of alpine rangeland, and this degradation weaken the ecological services function of alpine rangeland ecosystem; therefore, it was drew a conclusion that the out-of-balance gaming between ecological safety shelter zone and animal husbandry economy was the main external driver of alpine rangeland degradation. Based on the EPLF of alpine rangeland ecosystem, this study applied complex ecosystem field theory to establish the evaluation system and models of rangeland sustainable development, and the quantitative evaluation results showed that the development location of alpine rangeland ecosystem exceeded its maximum value of carrying capacity, and that development potential, harmonious degree and the sustainable development degree of alpine rangeland ecosystem was very low, indicating that alpine rangelands ecosystem was unsustainable development situation in the Naqu region in the northern Tibet.Second, the interaction mechanism of EPLF for alpine rangeland ecosystem was not linear internal relation, but was polybasic coupling, multidimensional linkage and multiple feedbacks with the interaction of population pressure, grazing pressure and environmental carrying capacity.The alpine rangeland ecosystem was balance and health when population and grazing pressure was below the threshold of environmental carrying capacity, and vice versa. The interaction of population pressure, grazing pressure and environmental carrying capacity developed an interaction mechanism of EPLF, which was not linear internal relation, but was polybasic coupling, multidimensional linkage and multiple feedbacks. The Equivalent of the Ecological Services Function (EESF) was designed to compare the relationship of EPLF in this study, and EESF was used to quantify the relationship among EPLF by determining the effect of on structure and functions of alpine rangeland ecosystem. The quantitative relationship among EPLF was used to estimate the population carrying capacity of alpine rangelands in the Naqu region under the different economic requirements. Here, per-capita income of well-to-do society and overcome-poverty life line for the herdsman proclaimed by China government in 2008 were considered as threshold to estimate the population carrying capacity of alpine rangelands in study region, the estimated results showed that the population carrying capacity of current alpine rangeland in well-to-do society and overcome-poverty life line decreased by 60% when compared to population carrying capacity of original rangeland. Based on the gross domestic product of animal husbandry of the Naqu region in 2008, the current population carrying capacity accounted for 96.3% of population carrying capacity in overcome-poverty life, but accounted for 489.2% of population carrying capacity in well-to-do society. The current population carrying capacity accounted for 14.2% and 85.9% of population in overcome-poverty life line and well-to-do society, respectively, when compared to population carrying capacity of original alpine rangeland. The current population carrying capacity accounted for accounted for 36% and 118.9% of estimated population carrying capacity in the overcome-poverty life line and well-to-do society in the Naqu region, respectively.Third,evaluation system and models of ecological services value of rangeland ecosystem were designed and established in this study, and they was used to evaluate ecological services value of alpine rangeland ecosystem in the Naqu region of northern Tibet. The evaluation results indicated that total annual ecological services value was 119.907 billion RMB, but total loss of annual ecological services value was 586.27 billion RMB.The 12 indicators with high contribution to ecological services function of alpine rangeland ecosystem were selected in this study by combing regional difference, spatial heterogeneity, and difference of economic development level at different areas. Based on the theory of ecological economic, the selected 12 indicator was applied to establish the index system and models to evaluate the ecological services value of alpine rangeland ecosystem of the Naqu region in northern Tibet. The evaluation results indicated that the total annual ecological services value of alpine rangeland was 119.907 billion RMB in the Naqu region, in which ecological services value of alpine steppe, alpine desert, alpine desert steppe, alpine meadow were 62.9%,1.5%, 8%, and 28.1% of the total ecological services value, respectively. This study also showed that ecological services value of original vegetation, slight degradation, moderate degradation, and severe degradation made up of 54.9%,29.3%,11%, and 4.8% of the total ecological services value, respectively. The loss of total annual ecological services value was 586.27 billion RMB due to alpine rangeland degradation in Naqu region, the average loss rate was 32.8% when compared to the total annual ecological services value of original alpine rangeland with 1800 billion RMB. The annual total economic income would reach 2.294 billion RMB when the rangeland was original in Naqu, this is to say, and the loss of ecological services value caused by rangeland degradation was 25.6 times of economic income from animal production in the original rangeland. This study further indicated that the loss of ecological services value caused by overgrazing one sheep unit was 13.9 times of economic value from overgrazing one sheep unit in the Naqu region of northern Tibet.Fourth, the function subarea and grading of alpine rangeland was used to establish the mechanism of ecological compensation for alpine rangeland, and the corresponding ecological compensation plan was designed in the Naqu region of northern Tibet.Four indicators, including productivity, importance of seasonal grazing, ecological services value, and ecological environmental sensitivity of each alpine rangeland subtype, were applied to design the functional subarea model in this study for determining ecological compensation regions. The alpine rangelands of the Naqu region in northern Tibet were classified into the production sector with moderate grazing, restoration sector with reducing livestock number, and conservation sector by anti-grazing, and they accounted for 24%,50%, and 26% of the total rangeland area of the Naqu region, respectively. These function subarea and grading of alpine rangeland was used to establish the mechanism of ecological compensation for alpine rangeland, in which measures of rewards and punishment for different function sector were presented. The corresponding ecological compensation plan was designed in the Naqu region of northern Tibet, in which the ecological compensation period was considered as 5 yeares and the total ecological compensation fund for alpine rangeland of the Naqu region was 35.77 billion RMB, which was allocated for the moderate production sector with 19.4 billion RMB, restoring sector with 15.77 billion RMB, and conservation sector with 0.6 billion RMB.Final, the framework of sustainable development strategy of alpine rangeland ecosystem was established, and the six countermeasures of sustainable development were presented to keep the health of alpine rangeland ecosystem in the Naqu region of northern Tibet.Based on government leading and herdsman participating, the framework of sustainable development strategy of alpine rangeland was established from aspect of institution, policy, project, fund, technology and management. The systems of cost accounting of environment and dynamic monitor of rangeland should be established. It was effort to carry out ecological compensation, perfect laws and regulations, ascertaining main function between ecological safety shelter zone and development of region economy, practice ecological emigration and develop ecological animal husbandry. The countermeasures of sustainable development of alpine rangelands were presented to keep the health of alpine rangeland ecosystem in the Naqu region of northern Tibet in the view of institutional arrangement, concept improvement, pattern innovation and technology integration.更多还原