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1.
中国草畜平衡状态时空演变指示的草地生态保护格局 总被引：2，自引：0，他引：2
中国草原牧区作为重要生态安全屏障和草地畜牧业生产基地,其草畜平衡状态直接影响草地退化与恢复,进而影响草地生态系统服务能力的强弱。本文分析了2000—2015年主要草原牧区草地植被覆盖、牧草供给、草畜平衡状态的时空变化特征,深入探讨草地退化与恢复及载畜压力下草地生态系统保护与恢复空间格局。结果表明：过去16年主要草原牧区草地面积净减少约163万hm2,6.7%的草地出现植被覆盖退化,而5.4%的草地呈现植被覆盖明显恢复。天然草地牧草供给量以增加为主,年增率约0.3 kg/hm2,然而其载畜压力亦持续增加,不考虑补饲的载畜压力指数高达3.8,除内蒙古东北部、青藏高原中部仍有载畜潜力,其余多处于超载状态;考虑实际冷季补饲的载畜压力指数约3.1,内蒙古中东部有所缓解;假设冷季全额补饲则载畜压力指数减至1.9,内蒙古、青藏高原等区域明显缓解。叠加上述数据,本文针对自然保护地、牧区、半农半牧区和农区等不同区域的草地生态保护格局,提出了平衡草地生态保护与畜牧生产利用的不同发展策略。 相似文献
2.
An abrupt ice and snow storm disaster which occurred in the spring of 2008 se-verely destroyed forests over a surprisingly large portion of southern China.A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area.The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests.The following results were obtained.(1) The extent of damage to plantations along the transect decreased in the order of slash pine > masson pine > mixed plantation > Chinese fir.Slash pine is an introduced species from southern America which is characterized by fast growth,low wood quality and rich oleoresin,and showed a damage rate of 61.3% of samples,of which 70.4% cannot recover naturally.Masson pine is the native pioneer species of forests with harder wood,and 52.5% were damaged due to turpentine,of which 60.9% cannot recovery naturally.Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%,lower than the mixed plantation.(2) From west to east along the transect,we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent,and a Cryp-tomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m.Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine ac-tivities,and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs.Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes,and Chinese fir at 500-900 m altitude showed a lighter damage extent.However,masson pine which was distributed above 400 m and planted in the 1960s,was severely damaged due to turpentine. 相似文献
3.
生态资源资产化、生态资产资本化是实现“两山”转化的一个重要途径,开展生态资产及其损益核算有助于生态系统的有效保护、科学管理和可持续利用。本文在借鉴国内外生态资产相关研究的基础上,构建了县域尺度生态资产及其损益核算技术体系,分析了1990—2018年中国县域生态资产的时空变化特征,明晰了造成生态资产损益的影响因素及作用机制,并针对具有不同生态资源类型、损益状况、驱动要素特征的县域提出了差异化的优化提升路径。结果表明：① 以农田、森林生态资源为主的县域数分别约占县域总数的45%和37%;1990—2018年中国县域生态存量资产的质量整体呈波动中上升趋势,而生态流量资产的变化趋势差异显著,近70%县域水源涵养量减少。② 生态流量资产价值呈现损与益态势的县域数分别约占44%和37%,空间分布呈现与“胡焕庸线”一致的分割特征,即西北广大地区县域明显增益,而东部和南部县域有所减损。③ 1990—2018年中国超过70%县域生态资产变化受气候变化与人类活动共同驱动,人类活动对生态资产增益县域的平均作用率约80%,而气候变化对生态资产减损县域的平均作用率约为60%。④ 综合分析,可将全国县域分为适应、减缓气候变化和生态资源修复、保护、管理5种类型,采用差异化的生态资产优化提升路径。 相似文献
4.
Until 2015,China had established 2740 nature reserves with a total area of 1.47million km~2,covering 14.8%of China’s terrestrial land surface.Based on remote sensing inversion,ecological model simulation and spatial analysis methods,we analyzed the spatial and temporal variations of fractional vegetation coverage(FVC),net primary production(NPP),and human disturbance(HD)in habitats of typical national nature reserves(NNRs)during the first 15 years of the 21st century from 2000 to 2015.And then the three indicators were compared between different NNR types and varied climate zones.The results showed that(1)the average 5-year FVC of NNRs increased from 36.3%to 37.1%,and it improved in all types of NNRs to some extent.The annual average FVC increased by 0.11%,0.84%,0.21%,0.09%,0.11%and 0.08%in NNRs of forest ecosystem,plain meadow,inland wetland,desert ecosystem,wild animal and wild plant,respectively.(2)The NPP annually increased by 2.06 g·m~(-2),1.23 g·m~(-2),0.28 g·m~(-2) and 0.4 g·m~(-2) in NNRs of plain meadow,inland wetland,desert ecosystem and wild animal,respectively.However,it decreased by 3.45 g·m~(-2) and2.35 g·m~(-2) in NNRs of forest ecosystem and wild plant respectively.(3)In the past 15 years,besides the slight decreases in the NNRs located at the Qinghai-Tibet Plateau and the south subtropical zone,HD enhanced in most of NNRs,especially HD in the warm temperate humid zone increased from 4.7% to 5.35%. 相似文献
5.
本文以贵州省东南部三州为研究区,运用连续生物量转换因子法和平均生物量法,通过2010年森林清查小班数据,建立了24类优势树种的森林植被碳密度与林龄之间的关系。同时,估算了1990-2010年间贵州省东南部森林植被生物量及其碳蓄积量,分析了碳蓄积量的时空变化特征,并预测出2050年该区域森林植被的固碳潜力。结果显示：（1）2010年贵州省东南部森林植被碳蓄积量为106.22 TgC,占贵州省森林植被碳蓄积量的63.01%,占全国森林植被碳蓄积量的1.36%;平均碳密度32.44 MgC/hm2,是贵州省森林植被平均碳密度的93%,全国森林植被平均碳密度的76%,碳密度空间分布呈现由西部向东部增加趋势且东部高于平均水平。（2）1990-2000年间森林植被碳蓄积量增加了30.67 TgC;2000-2010年间森林植被碳蓄积量增加了49.55 TgC,其中,退耕还林导致森林植被碳蓄积量增加了31.09 TgC。（3）以2010年为基准年,假设40 a后贵州省东南部森林面积保持稳定,且不考虑轮伐期的未来情景下,至2050年该区域森林植被碳蓄积量将达到153.38 TgC,其增量可达47.16 TgC,表明贵州省东南部森林具有较大的碳增汇潜力。 相似文献
6.
An abrupt ice and snow storm disaster which occurred in the spring of 2008 severely destroyed forests over a surprisingly large portion of southern China. A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area. The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests. The following results were obtained. (1) The extent of damage to plantations along the transect decreased in the order of slash pine > masson pine > mixed plantation > Chinese fir. Slash pine is an introduced species from southern America which is characterized by fast growth, low wood quality and rich oleoresin, and showed a damage rate of 61.3% of samples, of which 70.4% cannot recover naturally. Masson pine is the native pioneer species of forests with harder wood, and 52.5% were damaged due to turpentine, of which 60.9% cannot recovery naturally. Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%, lower than the mixed plantation. (2) From west to east along the transect, we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent, and a Cryptomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m. Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine activities, and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs. Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes, and Chinese fir at 500-900 m altitude showed a lighter damage extent. However, masson pine which was distributed above 400 m and planted in the 1960s, was severely damaged due to turpentine. 相似文献
7.
中国土地利用变化遥感研究的回顾与展望——基于陈述彭学术思想的引领 总被引：4，自引：0，他引：4
20世纪80年代以来中国社会经济快速发展带来的工业化、城市化正深刻影响着中国土地利用空间格局并影响到区域和国家生态与环境状况。在陈述彭先生指导下,1992年以来中国科学院建立起了完整的土地利用/覆盖变化遥感监测与数据分析技术路线,以及独特的分类体系和动态区划体系,奠定了中国LUCC信息平台的基础。本文在系统回顾陈述彭学术思想指导中国LUCC研究的基础上,面向国家需求与国际科技前沿梳理了我国LUCC研究的核心科学问题,并总结了中国科学院团队在最近20年LUCC研究取得的成果,包括土地利用/覆盖动态时空表征与分析模型、土地利用/覆盖变化过程及驱动机制、基于大数据和云计算的土地利用/覆盖变化探测方法、城市土地利用变化的区域气候/生态效应、气候变化与土地利用变化对农田生态系统的影响、林业活动的区域气候/生态效应,在此基础上对未来LUCC研究的前景进行了展望。 相似文献
8.
2005-2009年三江源自然保护区生态保护和建设工程生态成效综合评估 总被引：6，自引：1，他引：5
本文评价了三江源自然保护区生态系统宏观结构及涵养水源、保持水土、保护生物多样等主要生态服务功能,分析了自然保护区生态保护与建设工程的生态成效及其原因。结果显示,工程实施后,各自然保护区的土地覆被转类指数明显增加,生态系统宏观状况好转;保护区内草地生产力皆呈增加趋势,水域面积增加,食物供给能力提高,栖息地生境好转。森林类保护区的森林面积减少趋势得到遏制;湿地类保护区的湿地面积多呈增加趋势;草地类保护区的草地减少趋势缓解,荒漠化明显遏制,草地植被覆盖度有所增加;冰川类保护区多条冰川出现明显退缩导致冰川融水增多,有利于雪线以下草地净初级生产力的增加。 相似文献
9.
本文利用三江源南部1977年MSS、1990年TM和2004年TM三期遥感影像,结合1∶10万地形图、1∶100万草地图、1∶100万植被图和野外考察等资料,分析该区草地退化的时空变化特征和规律。结果表明:该区草地总体呈轻度退化,即为轻度破碎化退化、轻度覆盖度下降、轻度破碎化和轻度覆盖度下降复合型退化,共占研究区退化总面积的84.3%;轻度退化草地主要散布在唐古拉山东北部区域,中度退化草地多数分布于河流、居民点周围,草地轻度沙化/盐化退化主要发生在湖盆周围、河岸附近、滩地等区域。草地退化面积随海拔高度升高近似于正态分布,退化面积集中4 400～5 300m左右。1977～1990年和1990～2004年前后两期草地退化面积占研究区草地面积12.6%和18.9%,指示着草地状况的恶化。同时,对前后两个时段比较发现,草地退化发生以破碎化为先导,随后发生覆盖度持续降低。沼泽和沼泽化草甸的变化反映了区内气候的趋干化。另外,受气候条件等因素的影响,前期草地和沼泽变化有转好迹象。 相似文献
10.
近30年来青海省三江源区草地的土壤侵蚀时空分析 总被引：5，自引：0，他引：5
分析了青海省三江源区草地生态系统土壤侵蚀的空间差异,以及草地退化与土壤侵蚀的关系,并对该区近30年来土壤侵蚀的动念变化进行描述.结果表明,该区域微度以上土壤侵蚀面积占源区总面积的46.47%,而草地生态系统发生微度以上土壤侵蚀的面积比例达56.04%.源区土壤侵蚀类型是以冻融侵蚀伴随着水力侵蚀或风力侵蚀的复合侵蚀为主,... 相似文献