【作者】 秦立刚；

【导师】 王堃； 刘克思；

【作者基本信息】 中国农业大学 ， 草业科学， 2014， 博士

【摘要】 北方农牧交错带是北方农田生态系统和草地生态系统的交界地带,生态地位举足轻重,但地域的独特性导致了其生态功能脆弱,草地退化、土壤沙漠化等生态问题严重。近年来,国内外生态学界一直将生态系统服务功能价值评价做为难点和热点来研究,本研究在国内外对生态系统服务功能价值评价研究、生态足迹研究和区域土地利用格局与区域气候变化关系等理论和实践研究的基础上,以北方农牧交错带为研究区域,科学合理的选择相应指标,构建北方农牧交错带生态系统服务功能价值评价体系和生态足迹模型,对北方农牧交错带区域进行整体服务功能价值评价,通过生态足迹理论模型叠加验证,分析北方农牧交错带生态系统服务功能现状,并从区域下垫面与区域气候作用方面深入探究北方农牧交错带生态系统服务功能价值变化成因,阐明区域下垫面特征与区域环境气候响应机制。主要结论如下：(1)构建了包含7个服务功能指标的适合北方农牧交错带草地农田生态系统的服务功能评价体系,对北方农牧交错带区域生态系统服务功能价值评价结果表明：在1990年之前,研究区域以北方以西北牧区服务功能价值较高,1990年后开始,东部农区服务功能价值有所增加,较牧区和交错带高,到2005年以后,农区服务功能价值远高于牧区和交错带,牧区服务功能价值从1990年之后到2005年有所波动,但整体处于下降的趋势。北方农牧交错带服务功能价值1990年之后从内蒙古赤峰地区到陕西神木县地区形成一条狭长的价值低谷区—“生态裂谷”,一直到2004年,“生态裂谷”现象依然明显,并有向东北方向延长的趋势。(2)建立了北方农牧交错带生态足迹评价模型,通过对北方农牧交错带生态足迹测算,结果发现：1989-2004年研究区域人均生态足迹呈现不显著的波动性上升的趋势,以交错带和农区增加幅度最大。人均生态承载力变化不明显。生态赤字也是逐年增加,并以农区增加程度最强,其次为交错带。从15年整体平均来看,交错带人均生态足迹最高,人均生态承载力较低,处于非持续发展状态,在经济发展和人口膨胀的刺激下,交错带生态赤字显著也显著增加,需要极度重视。农区人均生态足迹增加趋势最快,生态赤字增加趋势最明显,生态问题不可忽视。(3)近60年来,研究区域年均温变化呈现显著上升趋势,年降水量呈现下降趋势。交错带与农区和牧区相比,年均温最高,并逐年增加;年降水量以较大的程度减少。表现出“温度高,降水少”的现象。交错带区域冰雹灾害、大风灾害、雷电灾害和洪涝灾害发生较牧区和农区更为频繁,同时由于交错带风蚀水蚀现象严重,同农区和牧区相比,高温低降水和频繁的灾害天气更容易造成土地退化沙化,亟需重视。研究区极端天气频次与草地农田比例呈现显著的负相关。草地农田比例与研究区域人口存在极显著的负相关,年均温与研究区域人口存在显著的正相关。由于区域人口增加,人类活动频繁改变了区域陆表下垫面的组成,影响陆表蒸散差,引起区域降水和气温变化,导致区域气候变化。更多还原

【Abstract】 As an ecological protective belt and water conservation district for eastern china, the agro-pastoral ecotone of northern China is located in transitional zone of farmland ecosystem and the grassland ecosystem, has important status. However, it is also the environmental fragile zone with serious ecological problems such as desertification and grassland shrinkage. Valuation of ecosystem services, providing an important basis for the ecological problems and establishing mechanism of ecological restoration, has become a hot topic of ecological research in the past few years. According to the research of ecosystem services value at home and abroad, a evaluation system has been established including7scientific and rational indicators, was used to evaluate ecosystem services values in agro-pastoral ecotone of china, also by using theory of landscape ecology, ecological economics, soil erosion, mathematical statistics and technology of GIS. The evaluation results was also verified by ecological footprint model, and in-depth analyzed from the relationship between land surface and regional climate change, in order to clarify the underlying surface area characteristics and regional environmental climate response mechanism. The main results were as follows:(1) An evaluation system has been established including7scientific and rational indicators, the results of ecosystem services value in agro-pastoral area of North China showed that:the value of pastoral area was higher than agricultural and agro-pastoral areas before1990, however the value of agricultural area was much higher than pastoral and agro-pastoral areas after2005. the value of pastoral area in the overall downward trend even fluctuated from1990to2005."Ecological rift valley" was emerged from Chifeng (Inner Mongolia) to Shenmu (Shanxi) based on ecosystem value after1990, and it was not disappeared until2004, it was extend to northeast conversely.(2) An ecological footprint model has been founded was used to verify ecosystem services value, the results showed that:Per capita ecological footprint were increased significantly from1989to2004in agro-pastoral area and farming area, while was wave ascending in pastoral area. The increasing extent of agricultural area was higher than pastoral and agro-pastoral areas. Changes in per capita ecological carrying capacity of study areas were not obvious. The ecological deficits also were increased year by year, and with a degree of increase in agricultural areas was the strongest, followed by zone. From an average of15years, agro-pastoral area was in a state of non-sustainable development with the highest per capita ecological footprint and less per capita ecological deficit, it was significant increasing in per ecological deficit stimulated by economic development and population growth. Lower ecological footprint per capita in farming area as a whole, but fastest-increasing trend, ecological deficit increase most obvious, ecological problems cannot be ignored.(3) The average annual temperature of study area was on the rise from1953to2012, while was stably with less volatile. The average annual temperature of agro-pastoral area was higher than the other areas and increased year by year, with the greater decreasing extent of annual rainfall. Hail damage, wind disasters, lightning and floods occur frequently in agro-pastoral area. Compared with the farming and pastoral areas, high temperature and low precipitation and frequent disasters, weather and more likely to cause land degradation, desertification, urgent attention must increase efforts. There were significant negative correlation between extreme weather frequency and proportion of grassland and farmland from1989to2000in agro-pastoral ecotone. Correlation between population number and proportion of grassland and farmland was significant negatively, however, completely opposite with correlation between population number and annual average temperature. The regional underlying surface composition were changed by increasing population and frequent human actives, and consequently brought in the regional climate change.更多还原