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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  
黄麟  翟俊  祝萍  郑瑜晗 《地理学报》2020,75(11):2396-2407
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.
乌兰图雅 《地理学报》2021,76(7):1722-1731
内蒙古草原是蒙古高原草原带的南部组成部分,是我国北方重要的生态屏障,草原生态修复任务重、压力大。本文以蒙古高原典型草原乌珠穆沁—温都尔汗样带为例,以1988—2016年5期TM数据为信息源,获取2016年样带草地利用信息基础上,按国别和年限对样带草地利用特征进行分析,揭示草地主要干扰因素,探寻有效的修复途径和可借鉴的国际经验。研究发现:① 草地面积占样带95.05%,均匀覆盖于整个样带;其他用地类型占比均不大,但分布相对集中,其中耕地集中于样带西北部蒙古国段,工矿用地、沙地、盐碱地集中于样带东南部内蒙古段。② 1988—2016年样带耕地面积减幅最大,为35.71%,集中位于蒙古国段;草地、水域面积逐年减少,在中国境内、境外变化趋势相同,但内蒙古段草地减幅大于蒙古国段且多转为未利用地;工矿用地面积增幅最大,为初期的近367倍,集中分布于内蒙古段;盐碱地、沙地面积逐年增加,在中国境内、境外的变化幅度相当。③ 草地是高原主要土地利用类型,放牧是草地主要利用方式,开矿是除放牧以外中国草地的主要干扰因子,蒙古国则为垦殖,内蒙古的草地干扰远大于蒙古国。草地退化与干旱化是蒙古高原面临的主要生态环境问题,在中国境内尤为突出。  相似文献   

3.
Livestock grazing is one of primary way to use grasslands throughout the world, and the forage-livestock balance of grasslands is a core issue determining animal husbandry sustainability. However, there are few methods for assessing the forage-livestock balance and none of those consider the dynamics of external abiotic factors that influence forage yields. In this study, we combine long-term field observations with remote sensing data and meteorological records of temperature and precipitation to quantify the impacts of climate change and human activities on the forage-livestock balance of alpine grasslands on the northern Tibetan Plateau for the years 2000 to 2016. We developed two methods: one is statical method based on equilibrium theory and the other is dynamic method based on non-equilibrium theory. We also examined the uncertainties and shortcomings of using these two methods as a basis for formulating policies for sustainable grassland management. Our results from the statical method showed severe overgrazing in the grasslands of all counties observed except Nyima (including Shuanghu) for the entire period from 2000 to 2016. In contrast, the results from the dynamic method showed overgrazing in only eight years of the study period 2000-2016, while in the other nine years alpine grasslands throughout the northern Tibetan Plateau were less grazed and had forage surpluses. Additionally, the dynamic method found that the alpine grasslands of counties in the northeastern and southwestern areas of the northern Tibetan Plateau were overgrazed, and that alpine grasslands in the central area of the plateau were less grazed with forage surpluses. The latter finding is consistent with field surveys. Therefore, we suggest that the dynamic method is more appropriate for assessment of forage-livestock management efforts in alpine grasslands on the northern Tibetan Plateau. However, the statical method is still recommended for assessments of alpine grasslands profoundly disturbed by irrational human activities.  相似文献   

4.
Grasslands have critically important ecological and economic values while most of them have been suffering from various degrees of degradation in China due to overgrazing. The “Forage-Livestock Balance” (FLB) policy has been implemented for more than a decade, aims to balance the relationship between forage productivity and grazing consumption of grasslands by livestock. According to the review of statistical data and literatures on policy evaluation, FLB-dominated subsidies for grassland ecological conservation policies are ineffective on grassland restoration, livestock reduction in some overloaded areas and improvement on herdsmen livelihood. To deal with the dilemma, we suggest a fundamental shift of strategy from controlling livestock numbers to maintaining and improving grassland health (MIGH) based on ecological theories, and promote the sustainable development of grassland in China. The results show that, FLB policy failed to obtain expected benefits mainly because it interfered with the herders' autonomous use of contracted grasslands along with the defects of its underlying theory and methodologies. Implementing reward and punishment based on ecosystem health will not only motivate herders to manage their grassland autonomously, but also be more scientific and feasible than FLB.  相似文献   

5.
Animal husbandry and crop farming are specialized for development in separate areas on the Tibetan Plateau. Such a pattern of isolation has led to current concerns of rangeland and farming system degradation due to intensive land use. The crop-livestock integration, however, has been proven to increase food and feed productivity thorough niche complementarity, and is thereby especially effective for promoting ecosystem resilience. Regional synergy has emerged as an integrated approach to reconcile rangeland livestock with forage crop production. It moves beyond the specialized sectors of animal husbandry and intensive agriculture to coordinate them through regional coupling. Therefore, crop-livestock integration (CLI) has been suggested as one of the effective solutions to forage deficit and livestock production in grazing systems. But it is imperative that CLI moves forward from the farm level to the regional scale, in order to secure regional synergism during agro-pastoral development. The national key R & D program, Technology and Demonstration of Recovery and Restoration of Degraded Alpine Ecosystems on the Tibetan Plateau, aims to solve the problems of alpine grassland degradation by building up a grass-based animal husbandry technology system that includes synergizing forage production and ecological functioning, reconciling the relationship between ecology, forage production and animal husbandry, and achieving the win-win goals of curbing grassland degradation and changing the development mode of animal husbandry. It is imperative to call for regional synergy through integrating ecological functioning with ecosystem services, given the alarming threat of rangeland degradation on the Tibetan Plateau. The series of papers in this issue, together with those published previously, provide a collection of rangeland ecology and management studies in an effort to ensure the sustainable use and management of the alpine ecosystems.  相似文献   

6.
羊啃食动力学模拟与内蒙古西部气候变化适应   总被引:1,自引:0,他引:1  
将定性分析、民主参与式评估和定量数值模拟方法结合起来,对阿拉善气候变化适应问题进行了简要评估并重点分析了土地退化、放牧和草原管理策略之间的关系。阿拉善主要的适应政策是禁牧和生态移民。禁牧后荒漠草原植被得到恢复,但移民增加了绿洲压力,过度开垦又造成周边土地沙化;过度抽取地下水致使水位下降并伴随咸水入侵和地表盐碱化。禁牧的另一个副作用是造成草原鼠害加重及火灾风险增加,生物多样性也呈现先升后降趋势。一些灌木因缺乏啃食出现退化迹象等,说明一定程度的啃食有利于维持草原生态平衡。因此,动物是草原生态系统不可或缺的成员之一。我们用一个包含动物啃食等的森林生态动力模式模拟了啃食动力学,结果表明,有限的放牧有利于草场更新并能充分利用草原资源;过度放牧导致草场退化并伴随羊群死亡。因此,需要将圈养和限制性放牧结合起来,制定可持续性适应政策。  相似文献   

7.
Although several previous studies in Inner Mongolia examined the effects of ecological conservation on the delivery of ecosystem services, they were often limited in scope (few ecosystem services were assessed) and often suffered from confounding by spatial variation. In this study, we examined the impact of conservation measures (changes in grassland utilization patterns) on the provision of selected ecosystem services in three types of grasslands (meadow steppe in Hulun Buir, typical steppe in Xilin Gol, and semi-desert steppe in Ordos) in Inner Mongolia. We examined five utilization patterns: no use (natural grasslands), light use, moderate use, intensive use, and recovery sites (degraded sites protected from further use). Through household surveys and vegetation and soil surveys, we measured the differences in ecosystem services among the different grassland utilization patterns. We also identified spatial factors that confounded the quantification of ecosystem services in different types of grasslands. We found that light use generally provided high levels of ecosystem services in meadow steppe and typical steppe, with the main differences in the supporting ecosystem services. Surprisingly, we found no consistently positive impacts of strict conservation activities across the sites, since the results varied spatially and with respect to differences in the land-use patterns. Our study suggests that appropriate grassland utilization patterns can enhance the supply of ecosystem services and reduce negative effects on both household livelihoods and the environment.  相似文献   

8.
Although several previous studies in Inner Mongolia examined the effects of ecological conservation on the delivery of ecosystem services, they were often limited in scope(few ecosystem services were assessed) and often suffered from confounding by spatial variation. In this study, we examined the impact of conservation measures(changes in grassland utilization patterns) on the provision of selected ecosystem services in three types of grasslands(meadow steppe in Hulun Buir, typical steppe in Xilin Gol, and semi-desert steppe in Ordos) in Inner Mongolia. We examined five utilization patterns: no use(natural grasslands), light use, moderate use, intensive use, and recovery sites(degraded sites protected from further use). Through household surveys and vegetation and soil surveys, we measured the differences in ecosystem services among the different grassland utilization patterns. We also identified spatial factors that confounded the quantification of ecosystem services in different types of grasslands. We found that light use generally provided high levels of ecosystem services in meadow steppe and typical steppe, with the main differences in the supporting ecosystem services. Surprisingly, we found no consistently positive impacts of strict conservation activities across the sites, since the results varied spatially and with respect to differences in the land-use patterns. Our study suggests that appropriate grassland utilization patterns can enhance the supply of ecosystem services and reduce negative effects on both household livelihoods and the environment.  相似文献   

9.
可持续性可通过区域生态足迹水平进行衡量。采用净初级生产力构建了内蒙古各盟(市)草地资源的均衡因子和产量因子。以每5 a为一期,测算了内蒙古草地1990—2020年的生态足迹,并结合人口分布数据刻画了生态足迹的空间分布状况;在此基础上应用土地可持续模型评价了内蒙古草地资源的可持续性。结果表明:(1) 内蒙古各盟(市)草地的产量因子差异较大,整体呈东高西低的特点。(2) 生态承载力在空间上也呈东高西低特点,30 a人均生态承载力整体呈小幅度下降趋势。(3) 人均生态足迹逐期上升,2000—2005年由生态盈余转变为生态赤字。生态足迹较高的区域集中在通辽市、锡林浩特市、二连浩特市、乌兰察布市南部和鄂尔多斯市东部地区。(4) 内蒙古草地资源可持续性逐期下降,由1990年的中度可持续性退化为2020年的弱不可持续性。可持续性退化严重的区域集中在呼和浩特市、包头市和乌海市。研究结果旨在为内蒙古草地资源的可持续利用提供可靠的理论基础。  相似文献   

10.
西部地区生态状况变化及生态系统服务权衡与协同   总被引:4,自引:0,他引:4  
西部大开发战略实施20年以来,一系列重大生态建设工程使得西部地区的生态状况和生态服务发生了重要变化,本文分析西部地区生态状况变化及其生态服务时空变化特征,并运用相关分析法研究其服务功能权衡协同关系。研究发现西部地区2000—2019年间:① 聚落和湿地生态系统面积显著增加,草地有逐年下降趋势。② 植被覆盖度呈波动上升趋势,存在年际差异且空间差异较大。③ 水源涵养服务有轻微下降趋势,下降区域主要分布在藏东南地区、三江源西部地区、喀斯特石漠化地区等;土壤保持服务波动中呈上升趋势,上升区域主要黄土高原地区、川滇西部地区、藏西北地区、藏东南地区等;防风固沙服务呈下降趋势,大幅下降区域主要位于内蒙古中西部地区、西藏和北疆部分地区。④ 生态系统供给与水源涵养、土壤保持主要为协同关系,与防风固沙主要为权衡关系且分布在农牧交错带地区。⑤ 生态工程区内生态系统服务协同程度大于非工程区。定量评估生态系统服务变化及其权衡协同关系有助于进行科学化生态管理,最大化生态效益。  相似文献   

11.
Modern dust storms in China: an overview   总被引:4,自引:0,他引:4  
This paper discusses the sources, spatial distribution, frequency and trend of dust storms in China. Most dust storms in China originate from one of three geographic areas: the Hexi (River West) Corridor and western Inner Mongolia Plateau, the Taklimakan Desert, and the central Inner Mongolia Plateau. Dust is most likely from deteriorated grasslands, Gobi, alluvial, lacustrine sediments and wadis at the outer edge of deserts. But deserts themselves contribute only slightly to the dust storm directly. Two geographic areas frequently have dust storms: one is in the western Tarim Basin, a ground surface of deteriorated land and wadi, but it only affects its neighboring areas, and the other one is in the western Inner Mongolia Plateau, a ground surface of Gobi, alluvial and lacustrine sediments, but it causes most of the dust storms in north China. Generally speaking, dust storms have reduced in most regions of China from the 1950 to 2000. Dust storms are highly correlated with human activities and climate changes.  相似文献   

12.
甘南草地类型的生态经济价值与功能及其分类经营   总被引:10,自引:0,他引:10  
根据山区景观所具有的3层次功能和指标体系选取的原则,从美学、社会、生态3个方面,初步构建了4个层次的评价指标体系。在此基础上建立综合评判模型,应用于北京市怀柔区9个乡镇,得到如下结果:景观功能评价综合指数处在"较好"标准的有宝山镇和怀北镇;在"一般"标准的有喇叭沟门乡、雁栖镇、九渡河镇、长哨营乡;处在"较差"标准的有渤海镇、玻璃庙镇、汤河口镇。评价结果基本与实际相符,说明建立的评价指标体系与模型是可行的。  相似文献   

13.
本文基于气象、遥感数据,运用RWEQ模型,结合风蚀季节的植被盖度变化对近30年的土壤风蚀量和植被的防风固沙服务功能的时空变化趋势进行了定量评估,揭示了植被盖度变化对防风固沙服务功能的影响。研究表明:中国北方多年平均土壤风蚀量为160.1亿t,并处于下降趋势,土壤侵蚀强度大的区域主要集中在各大沙漠区和植被盖度较低的草地,且春季为我国土壤风蚀的多发期,占全年风蚀量的45.93%;中国北方多年平均防风固沙量为203.1亿t;防风固沙服务功能保有率的分布特征表现为由东南到西北逐渐降低的趋势;工程实施后春季植被盖度的提升区主要集中在黄土高原、青藏高原、河北北部、内蒙古东部以及东北地区;大部分区域的春季植被盖度减小(提高)与防风固沙的服务保有率的下降(提升)呈显著正相关(r0.7,p0.01);前后两个十年相比较草地生态系统的防风固沙服务功能提升幅度最大(2.02%),其次为林地(1.15%)、农田(0.99%)和荒漠(0.86%)。  相似文献   

14.
内蒙古是我国土壤风力侵蚀较为严重的地区之一,同时也是我国土地利用方式剧烈变化的地区之一。依据两期土地利用数据以及相应年代的土壤风力侵蚀数据,研究了20世纪90年代末期内蒙古自治区土地利用和风力侵蚀的静、动态格局。根据土地利用和风力侵蚀的空间分布及动态变化特点,设计了内蒙古土地利用-风力侵蚀动态区划,基于该区划详细讨论了内蒙古不同地区占主导地位的土地利用动态与风力侵蚀动态,由此揭示了两者之间存在的驱动--被驱动关系。研究发现,在20世纪90年代末期,内蒙古土地利用和风力侵蚀的基本格局没有太大变化,但风力侵蚀强度在总体上增强了;土地利用的变化主要反映为草地的退化和耕地的扩张。土地利用动态与风力侵蚀动态有着良好的时空对应关系:草地的退化与耕地的扩张导致了显著的风力侵蚀增强,而草地的改善以及耕地的收缩对风力侵蚀的影响不如前者明显,这表明了土地利用动态对风力侵蚀动态正、反向驱动的不平衡性。  相似文献   

15.
甘宁蒙陕农牧交错区不宜大规模开垦   总被引:7,自引:3,他引:4  
通过对甘宁蒙陕农牧交错区的自然特征和生态功能、人类活动对该区环境的影响、水资源状况、国内外开垦草原的教训等方面的分析、论证,说明该区不宜大规模开垦,并提出该区生态保护与建设的对策。  相似文献   

16.
Overgrazing has been considered one of the maj or causes that trigger shrub encroachment of grassland. Proliferation of shrubs in grassland is recognized as an important indicator of grassland degradation and desertification. In China, various conservation measures, including enclosures to reduce livestock grazing, have been taken to reverse the trend of grassland desertification, yet shrubs have been reported to increase in the grasslands over the past decades. In late 2007, we set up a 400-m-by-50-m exclosure in a long-term overgrazed temperate grassland in Inner Mongolia, with the ob- jective to quantify the spatiotemporal relationship between vegetation dynamics, soil variables, and grazing exclusion. Soil moisture was continuously monitored within the exclosure, and cover and aboveground biomass of the shrubs were measured inside the exclosure in 2007, 2009, 2010, 2012, and 2013, and outside the exclosure in 2012 and 2013. We found the average shrub cover and biomass significantly increased in the six years by 103 % and 120%, respectively. The result supported the hypothesis that releasing grazing pressure following long-term overgrazing tends to trigger shrub invasion into grassland. Our results, limited to a single gradient, suggest that any conservation measures with quick release of overgrazing pressure by enclosure or other similar means might do just the opposite to accelerate shrub en- croachment in grassland. The changes in vegetation cover and biomass were regressed on the temporal average of the soil moisture content by means of the generalized least square technique to quantify the effect of the spatial autocor- relation. The result indicates that the grass cover and biomass significantly increased with the top, but decreased with the bottom layer soil moisture. The shrub cover and biomass, on the other hand, decreased with the top, but increased with bottom soil moisture, although the regression coefficients for the shrubs were not statistically significant. Hence this study supports the two-layered soil model which assumes grasses and shrubs use belowground resources in dif- ferent depths.  相似文献   

17.
Enclosure is one of the most widely used management tools for degraded alpine grassland on the northern Tibetan Plateau, but the responses of different types of grassland to enclosure may vary, and research on these responses can provide a scientific basis for improving ecological conservation. This study took one site for each of three grassland types (alpine meadow, alpine steppe and alpine desert) on the northern Tibetan Plateau as examples, and explored the effects of enclosure on plant and soil nutrients by comparing differences in plant community biomass, leaf-soil nutrient content and their stoichiometry between samples from inside and outside the fence. The results showed that enclosure can significantly increase all aboveground biomass in these three grassland types, but it only increased the 10-20 cm underground biomass in the alpine desert. Enclosure also significantly increased the leaf nutrient content of the dominant plants and contents of total nitrogen (N), total potassium (K), and organic carbon (C) in 10-20 cm soil in alpine desert, thus changing the stoichiometry between C, N and P (phosphorus). However, enclosure significantly increased only the N content of dominant plant leaves in alpine steppe, while other nutrients and stoichiometries of both plant leaves and soil did not show significant differences in alpine meadow and alpine steppe. These results suggested that enclosure has differential effects on these three types of alpine grasslands on the northern Tibetan Plateau, and the alpine desert showed the most active ecological conservation in the responses of its soil and plant nutrients.  相似文献   

18.
生态保护的成本是生态补偿标准的核心组成部分,一般由直接成本、机会成本和发展成本构成。本文以羌塘自然保护区涉及的那曲地区为例,采用恢复成本法和机会成本法对牧民参与野生动物保护的直接成本和机会成本进行了核算。研究过程中,借用中国草地承载力评估中的标准羊单位,把草地生态系统、草食性野生动物和价值评估有机地联系起来,为草原地区野生动物保护的生态补偿提供了一个有效的评估工具。评估结果表明,那曲地区牧民参与野生动物保护的成本是每年5.69亿元,其中直接成本是1.19亿元,机会成本是4.5亿元,机会成本占总成本的79%。机会成本是由于草食性野生动物的啃食与踩踏导致草场必须禁牧致使牧民放弃的经济收入。显然,羌塘自然保护区草食性野生动物对草场的损害构成了生态补偿的主体。如果按照那曲地区中度以上退化草地的面积计算,则牧民保护野生动物的单位面积成本是每年57元,按照那曲地区人口计算,参与野生动物保护的人均成本是每年1482元。这一结果并不等于生态补偿标准,但可以作为补偿标准的低限。  相似文献   

19.
Arbuscular mycorrhizal fungi(AMF) are universally mutualistic symbionts that colonize the fine roots of most vascular plants. However, the biogeographical patterns and driving factors of AMF diversity of plant roots in grasslands are not well investigated. In this study, we used high-throughput sequencing techniques and bioinformatics to evaluate the AMF richness of 333 individual plant roots in 21 natural grassland ecosystems in northern China, including the Loess Plateau(LP), the Mongolian Plateau(MP), and the Tibetan Plateau(TP). The AMF richness showed a significant parabolic trend with increasing longitude. In regional situations, the AMF richness in the grasslands of the MP(60.4 ± 1.47) was significantly higher than those of the LP(46.4 ± 1.43) and TP(44.3 ± 1.64). Plant traits(including plant families, genera, and functional groups) explained the most variation in the AMF richness across China's grasslands, followed by energy and water; soil properties had the least effects. The results showed the biogeographical patterns of the AMF richness and the underlying dominant factors, providing synthetic data compilation and analyses in the AMF diversity in China's grasslands.  相似文献   

20.
过牧及封育对红砂荒漠植被演替的影响   总被引:36,自引:12,他引:24  
红砂灌丛植被是我国西北荒漠地区的主要放牧地,并在生态保护中具重要作用。本试验以内蒙古阿拉善盟不同过牧强度下的退化(轻度、中度和重度)红砂(Reaumuria soongorica)+无芒隐子草(Cleistogenes songorica)荒漠草地为对象。首次研究报道了不同过牧梯度和围栏封育对红砂植被演替的影响。经过6a过牧(平均1.8只羊·hm-2),植被总盖度已由12%降至8%,平均每年盖度绝对值下降0.7%。随草地过牧加重红砂灌丛在逐渐消亡,在中度和重度退化样地的盖度已分别较轻度样地(7.5%)下降了74%和84% (P<0.05);质量差或产量低的草本在增加;无芒隐子草和匍根骆驼蓬(Peganum nigellastrum)的增加可分别作为该类草地中度和重度过牧演替的指示种。短期封育效果十分显著,封育一年的各样地平均较放牧样地比,植被盖度绝对值提高了1.7%,产草量增加2188%,红砂种子产量是放牧样地的371倍。然而,优势种红砂的产草量和盖度在封育期的相对恢复速率皆随样地退化加重而显著降低(P<0.05),重度退化区盖度封育当年的恢复速率为0。所以,封育是保护和恢复我国红砂荒漠植被的有效措施,但封育宜尽早开始,否则,红砂将恢复缓慢或难以复存。  相似文献   

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