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1.
治理草原退化是我国草原管理的重点和难点。我国目前关于草原退化判断、退化程度、原因及治理等系列问题的确定几乎皆以科学研究结果为依据,而忽视了牧户作为草原直接使用者和管理者的重要性。牧户对草原有自己的判断和认知,其与科学方法研究之间的矛盾已经影响到草原生态保护政策的有效实施。本研究以内蒙古东部草甸草原牧户尺度草原为研究对象,借助牧户调研和野外调查相结合的方法,将牧户划分为高、中、低3个经济水平,并运用Condition-Vigor-Organization-Resilience(CVOR)指数评价法,分析评价草原生态系统健康状况。研究结果显示,牧户对草原健康状况的感知主要从植被、土壤、牲畜等方面,与科学方法评价指标选取具有相似性;牧户感知和CVOR指数法评价结果具有一致性,均判定草原生态系统呈现不同程度退化;统计检验显示牧户对植被、土壤、牲畜影响等指标变化感知方面均不存在显著差异(P0.05),CVOR指数法下不同经济水平牧户草场健康指数之间亦无显著差异(P0.05),两种方法均显示不同经济水平牧户草场退化程度无显著差异(P0.05)。研究证实了牧户感知在指标选取、评价结果方面具备用于准确评价草原健康状况的可行性和可信度。两种方法相互补充,将有利于更加准确、实时动态监测和评价牧户尺度草原生态健康状况,为调整优化畜牧业生产实践提供指导和草原生态保护和建设政策的有效实施提供保障。  相似文献   

2.
内蒙古典型草原生态系统健康评价   总被引:11,自引:4,他引:7  
以草原生态系统中的植物-土壤-大气界面的关键生态过程为基础,结合典型草原生态系统的群落特征及其退化演替模式,并考虑水分因子的限制作用,在确定生态系统健康评价模式(参照)系统和基况评价指标的同时,建立了典型草原生态系统健康评价的CVOR综合指数的计算模型和方法.通过分析放牧压力和围封保育对内蒙古典型草原生态系统健康的影响,检验了CVOR综合指数的可行性,可为草原生态系统健康管理提供一个综合、简单、准确、宜行的评价方法.  相似文献   

3.
北方草原牧户心理载畜率与草畜平衡生态管理途径   总被引:2,自引:0,他引:2  
侯向阳  尹燕亭  王婷婷 《生态学报》2015,35(24):8036-8045
探讨牧户心理载畜率与草畜平衡生态管理的途径对于草原有效减畜、遏止草原退化、实现可持续发展具有重要意义。从生态学和社会科学相结合的角度,采用问卷调查、情景实验及综合分析等多种方法,探讨了北方草原牧户心理载畜率的存在、计算和影响因素,以及牧户生产决策行为特征和可能的生态管理途径。研究发现,在草甸草原、典型草原和荒漠草原,牧户行为属"有限理性",是有限理性的"生态经济人",风险规避是其基本特征,牧户生产决策表现出禀赋效应、损失厌恶、框架效应等;牧户草场所属草原类型和牲畜存栏数显著影响牧户对草场超载的认知和判断,在不同草原类型区,户主文化水平、性别、民族和是否嘎查干部等亦显著影响牧户对超载的认知和判断;需采取基于进化博弈的分步式、合作式及示范引导式的适应性减畜的生态管理途径,以实现牧户心理载畜率向生态优化载畜率的转移,实现优化牧户生产方式、减少牲畜数量、治理草原退化、北方牧区生态和牧民经济双赢的目标。  相似文献   

4.
内蒙古荒漠草原牧户对气候变化的感知和适应   总被引:9,自引:1,他引:8  
Han Y  Hou XY 《应用生态学报》2011,22(4):913-922
荒漠草原是气候变化影响的脆弱和敏感地区.荒漠草原的牧户主要依赖天然草原维持生计,正面临着严峻的气候变化挑战.本文采用问卷调查的实证分析方法,在获取内蒙古苏尼特右旗荒漠草原牧户对气候变化和极端气候事件感知和适应的第一手资料基础上,分析了荒漠草原牧户对气候变化趋势和极端气候事件感知和适应的现状与行为特征.结果表明:在降水稀少、气象灾害频繁发生的荒漠草原,干旱是影响范围最广、影响程度最深、发生频率最高的极端气候事件;牧户不仅对干旱的敏感度远高于其他极端气候事件,而且对大风、沙尘暴和大雪等极端气候事件的深刻感知伴随着对干旱的感知而产生;相对于长期气候变化的感知,牧户对短期气候变化趋势的感知更深刻、准确,并主要依据近10年气候变化的感知结果来判断较长期气候变化的总体趋势;牧户认为,气候变化在很大程度上影响了牲畜健康和草场产量,但牧户应对气候变化的行为相对单一,且多为自发性被动适应,缺乏行之有效的主动适应.  相似文献   

5.
植被是陆地生态系统的主体,是保障生态质量的基础,也是基于自然的生态系统增汇、实现“碳中和”的重要利器。植被是生态质量评价的核心要素,但目前的生态质量评价研究中所用到的植被指标多是通过遥感反演或者气象指数模型计算得到的,而基于典型生态系统尺度地面调查的植被观测数据更直接、更准确,数据也很丰富,却很少用于生态质量评价,也缺乏系统的评价指标体系。通过文献研究、专家研讨和问卷调查,并借鉴群落退化演替和生态系统长期监测研究的理论基础,构建基于地面调查的植被生态质量综合评估指标体系。该指标体系整体分为三级,一级综合指数由群落结构指数、物质生产指数、生物多样性指数、群落发展或者演替趋势4个二级分项指标构成,二级分项指标由12—14个三级指标组成,不同植被类型各有其特征指标。该体系将完善我国多尺度陆地生态系统的生态质量评价指标体系,为新时期国家生态质量评价提供科学建议,为我国生态文明建设提供技术支撑。  相似文献   

6.
以3种不同退化程度的温带典型草原(大针茅轻度退化、中度退化和重度退化)为研究对象,研究植被退化对温带典型草原土壤及根系碳氮含量及储量的影响。结果显示:(1)植被退化对地下根系碳含量影响不显著(P0.05),而对地下根系氮含量的影响显著(P0.05),中度退化样地根系氮含量显著高于轻度退化和重度退化样地(P0.05)。(2)植被退化对根系碳氮储量影响显著(P0.05),根系碳氮储量随着土层深度增加而减少,总根系碳氮储量随退化程度加剧而降低。(3)土壤有机碳、总碳和总氮含量及储量均受退化程度和采样深度的影响显著(P0.05),其含量随着土壤深度的增加而显著减少,随退化程度加剧而显著降低(P0.05)。(4)土壤是根系-土壤系统碳氮储存的最主要场所,储量占比90%以上。虽然土壤碳氮储量均存在表层聚集现象,但表层储量所占比例在各样地间差异显著(P0.05)。  相似文献   

7.
内蒙古典型草原生态系统定位研究最新进展   总被引:9,自引:0,他引:9  
中国科学院内蒙古草原生态系统定位研究站最近几年在草原生态系统多功能、草原生态系统碳循环与温室气体、气候变化对植物群落结构影响长期观测、草原生态系统退化与恢复过程、草原生态系统硫生物地球化学循环、放牧生态系统管理等领域取得较大进展。研究结果指出,农垦活动使有机碳损失34%,草原植被——土壤系统是甲烷的弱汇;20多年来,这一地区气候变化有变暖趋势,冬季增温明显,春季干旱进一步加剧,影响初级生产力生产;系统提出草原退化是草原生态系统退化,并对退化阶段进行了划分;在内蒙古冷蒿小禾草退化草原施用硫肥对提高初级生产力与羊毛性能方面有明显效果。  相似文献   

8.
围封是退化草原生态系统恢复的有效措施之一,已在中国北方草原地区实施多年并取得良好的效果。由于不同退化草原生态系统具有完全不同的植被和土壤条件,围封对不同退化草原植物群落和土壤的恢复是否具有一致的影响,目前仍不清楚。对内蒙古地区轻度、中度和重度退化荒漠草原分别设置6年围封后,对植物群落特征和土壤理化性质进行了调查和测定。研究结果发现,围封显著提高了3种退化荒漠草原短花针茅(Stipa breviflora)和无芒隐子草(Cleistogenes songorica)种群以及群落的高度、盖度和地上生物量(P<0.05),表明围封从多组织层次使退化草原植物群落得到有效的恢复。围封总体提高了轻度和中度退化荒漠草原植物多样性,但降低重度退化荒漠草原的植物多样性。重度退化荒漠草原在围封后群落高度、盖度和地上生物量恢复效率显著高于轻度和中度退化的(P<0.05),表明围封对重度退化荒漠草原植被恢复更加有效。除轻度退化外,围封显著降低中度和重度退化荒漠草原土壤全碳、全氮、全磷、有效氮和速效磷含量(P<0.05),但对3种退化荒漠草原的土壤水分含量无显著影响,表明围封对不同退化荒漠草原土壤的影响具有滞后性。研究为荒漠草原围封成效评估提供理论指导和退化荒漠草原生态系统科学合理实施围封政策提供科学依据。  相似文献   

9.
荒漠草原(生态区)横贯我国西北地区东部,生态地位十分重要。近二十年来,通过封育禁牧、退耕还林(草),植被覆盖显著改善,但是生态系统质量和稳定性依然不高。由于长期将荒漠草原单纯视作草原的一部分,对其生态系统过渡性、脆弱性和复杂性本质特征认识不足,造成了荒漠草原生态学研究与区域生态建设实践之间不同程度的脱节。在分析荒漠草原生态区未来在我国生态安全格局中突出的但是被一定程度上忽视的地位的基础上,进一步归纳了荒漠草原生态系统的一般特征,指出了生态恢复与重建研究中存在的主要问题。进而以人工植被引入荒漠草原生态工程为案例,分析了人工植被驱动荒漠草原生态恢复与重建的过程与机制,归纳了“植被-水文-土壤”互馈作用驱动生态系统层级响应模式,并展望了今后的发展趋势与研究方向。  相似文献   

10.
以福建省长汀县朱溪小流域为研究对象,通过野外调查、室内分析以及遥感影像提取相结合的方法获取数据。利用Matlab7.0软件建立BP神经网络生态恢复模型,定量评价退化生态系统的恢复程度。选择土壤理化性质(有机质、全N、全P、全K、容重和p H)、植被结构(植被盖度)、物种多样性指数(Shannon-Wiener指数)和热环境(地表温度)等4个方面的9个指标建立退化生态系统评价体系,并作为生态恢复模型的输入层数据,生态恢复度作为输出层数据。使用Matlab7.0进行数据预处理、样本训练、样本检验并建立生态恢复模型。利用建立的生态恢复模型对整个朱溪小流域生态恢复度进行定量评价。结果表明,生态恢复模型预测结果与流域生态恢复的实际情况基本吻合,利用BP神经网络模型定量评价退化生态系统的恢复程度具有可行性。朱溪小流域内生态恢复程度极低的区域面积仅占0.94%,95.48%区域为中等恢复程度,说明生态保护措施已初见成效;生态恢复程度高的区域面积仅占3.62%,意味着未来仍需加强治理和保护工作。  相似文献   

11.
本文将定位研究与路线考察相结合,将放牧影响下草原的动态演替及其在牧压梯度上的空间变化相对比,研究了内蒙古主要草原草场的放牧退化模式,并在此基础上初步探讨了判别草场退化的数量指标和退化监测专家系统。1)植物种与牧压关系的分析,区别出放牧的定性和定量指示植物及宜中牧植物,并划分植物为不同的放牧生态种组。2)退化草原恢复过程的研究表明,根茎禾草的恢复快于丛生禾草;群落恢复过程是单稳态的,且恢复演替动态与其牧压梯度上的空间变化相对应。3)内蒙古高原主要草原草场在持续放牧影响下均趋同于冷蒿(Artemisia frigida)草原。冷蒿是最可靠的正定量放牧指示植物,但同时又是优良牧草和草原退化的阻击者。4)讨论了草原草场退化的概念,论述了草原逆向演替与草场退化的区别和联系,提出了区分草原的逆向演替为草场熟化和退化两个过程,并依草场群落与牧压的关系建立了判定草场是否退化及退化程度的数量指标。5)初步设计了草原草场退化监测—决策专家系统,包括监测、判别和决策三个步骤。  相似文献   

12.
刘兴元  龙瑞军 《生态学报》2013,33(11):3404-3414
根据藏北那曲高寒草地的生产力、季节放牧重要性、生态服务价值、生态环境敏感性,构建了基于草地亚类的功能分区模型,从空间上将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,据此构建了基于高寒草地功能分区的分级生态补偿模式,设计了高寒草地生态补偿的组织管理体系及流程、生态补偿的损益评估机制和约束奖惩机制;提出了针对不同功能区的生态补偿方案.根据藏北那曲高寒草地功能分区结果和不同功能区生态补偿内容和目标,确定生态补偿周期为5a,核算出适度生产功能区、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,每年分别需补偿资金3.88亿元、3.16亿元和0.12亿元,5a全区共需补偿资金35.77亿元,年需7.16亿元.通过对高寒草地的功能分区分级生态补偿,对提高高寒草地的生态保护能力,增加牧民的经济收入,促进藏北高寒草地生态系统的可持续发展具有重要的理论和实践意义.  相似文献   

13.
In the countries surrounding the Mediterranean basin, most of the semi-natural grazing lands are covered by rangelands. Rangelands can be defined as highly heterogeneous natural vegetation communities with high conservation value, growing in harsh environments (poor soils, unfavourable climatic conditions). In the recent socio-economic context, traditional livestock grazing practices that enabled one to reconcile rangeland preservation and animal production no longer apply, especially because they require labour that has become scarce and costly. The consequence is rangeland degradation, due to underutilization in Southern Europe, and overutilization in Northern Africa. We analysed issues raised by rangeland utilization in livestock farming systems of the Mediterranean basin. Based on a review of the scientific literature about rangeland utilization in this area, we argue that the best way to reconcile animal production and rangeland preservation would be to promote management practices allowing animals to express their adaptative capacities in feeding behaviour and productive response. In order to propose management practices adapted to extensive and simplified systems, we conclude that research efforts should focus on: (i) proposing a functional characterization of vegetation heterogeneity at the scale of the vegetation community, (ii) validating the criteria determining animals' foraging behaviour on Mediterranean rangelands, (iii) developing and using simulation models to test management strategies against seasonal and long-term variability in climatic conditions and (iv) evaluating the potential of modern technologies for improving rangeland utilization.  相似文献   

14.
Abstract Functional integrity is the intactness of soil and native vegetation patterns and the processes that maintain these patterns. In Australia's rangelands, the integrity of these patterns and processes have been modified by clearing, grazing and fire. Intuitively, biodiversity should be strongly related to functional integrity; that is, landscapes with high functional integrity should maintain biodiversity, and altered, less functional landscapes may lose some biodiversity, defined here as the variety and abundance of the plants, animals and microorganisms of concern. Simple indicators of biodiversity and functional integrity are needed that can be monitored at a range of scales, from fine to coarse. In the present paper, we use examples, primarily from published work on Australia's rangeland, to document that at finer patch and hillslope scales several indicators of landscape functional integrity have been identified. These indicators, based on the quantity and quality of vegetation patches and interpatch zones, are related to biodiversity. For example, a decrease in the cover and width (quantity) and condition (quality) of vegetation patches, and an increase in bare soil (quantity of interpatch) near cattle watering points in a paddock are significantly related to declines in plant and grasshopper diversity. These vegetation patch‐cover and bare‐soil indicators have been monitored traditionally by field‐based methods, but new high‐resolution, remote‐sensing imagery can be used in specific rangeland areas for this fine‐scale monitoring. At intermediate paddock and small watershed scales, indicators that can be derived from medium‐resolution remote‐sensing are also needed for efficient monitoring of rangeland condition (i.e. functional integrity) and biodiversity. For example, 30–100‐m‐pixel Landsat imagery has been used to assess the condition of rangelands along grazing gradients extending from watering‐points. The variety and abundance of key taxa have been related to these gradients (the Biograze project). At still larger region and catchment scales, indicators of rangeland functional integrity can also be monitored by coarse‐resolution remote‐sensing and related to biodiversity. For example, the extent and greenness (condition) of different regional landscapes have been monitored with 1‐km‐pixel satellite imagery. This regional information becomes more valuable when it indicates differences as a result of land management. Finally, we discuss potential future developments that could improve proposed indicators of landscape functional integrity and biodiversity, thereby improving our ability to monitor rangelands effectively.  相似文献   

15.
Land‐use change has resulted in rangeland loss and degradation globally. These changes include conversion of native grasslands for row‐crop agriculture as well as degradation of remaining rangeland due to fragmentation and changing disturbance regimes. Understanding how these and other factors influence wildlife use of rangelands is important for conservation and management of wildlife populations. We investigated bat habitat associations in a working rangeland in southeastern North Dakota. We used Petterson d500x acoustic detectors to systematically sample bat activity across the study area on a 1‐km point grid. We identified calls using Sonobat autoclassification software. We detected five species using this working rangeland, which included Lasionycteris noctivagans (2,722 detections), Lasiurus cinereus (2,055 detections), Eptesicus fuscus (749 detections), Lasiurus borealis (62 detections), and Myotis lucifugus (1 detection). We developed generalized linear mixed‐effects models for the four most frequently detected species based on their ecology. The activity of three bat species increased with higher tree cover. While the scale of selection varied between the four species, all three investigated scales were explanatory for at least one bat species. The broad importance of trees to bats in rangelands may put their conservation needs at odds with those of obligate grassland species. Focusing rangeland bat conservation on areas that were treed prior to European settlement, such as riparian forests, can provide important areas for bat conservation while minimizing negative impacts on grassland species.  相似文献   

16.
Sustainable Rangeland Grazing in Norse Faroe   总被引:1,自引:1,他引:0  
The introduction of domestic livestock, particularly sheep, and rangeland grazing by Norse settlers to Faroe during the ninth century has generally been described as a major pressure on a sensitive landscape, leading to rapid and widespread vegetation change and contributing to land degradation. This view has, however, been developed without consideration of Norse grazing management practices which may have served to minimize grazing impacts on landscapes as well as sustaining and enhancing vegetation and livestock productivity. These alternative scenarios are considered using a historical grazing management simulation model with Faroese climate and vegetation inputs and given archaeological, historical and palaeoenvironmental parameters. Three contrasting rangeland areas are investigated and, based on the maximum number of ewe/lamb pairs the rangeland could sustain, modeling suggests that utilizable biomass declined with the onset of grazing activity, but not to a level that would cause major changes in vegetation cover or contribute to soil erosion even under climatically determined poor growth conditions. When rangeland areas partitioned into what are termed hagi and partir are modeled, grazing levels are still within rangeland carrying capacities, but productivities are variable. Some rangeland areas increase biomass and livestock productivities and biomass utilization rates while other rangeland areas that were too finely partitioned were likely to suffer substantial decline in livestock productivity. Partitioning of rangeland is a likely contributor to long-term differentiation of landscapes and the relative success of settlements across Faroe beyond the Norse period.  相似文献   

17.
Based on 224 face-to-face household surveys in an ecologically fragile grazing area in China’s Inner Mongolia Autonomous Region, this study analyzes herder (pastoralist) adaptive capacity for coping with climate change. The Composite Indicator Framework Method and Entropy Weighting Method were applied to calculate each herder’s Adaptive Capacity Index (ACI) based on 16 indicators from seven determinants of adaptive willingness and adaptive capital. Results show that herders have an average ACI value of 0.40. Classifying herders into three groups of relatively high, medium, and low ACI values, we find that financial capital and social capital are the most significant determinants of herder adaptive capacity. Improving financial services and building herder social capital would be the most effective ways of enhancing adaptive capacity for coping with climate change. The methods and indicators developed can be generalized to other similar areas to facilitate better policy interventions for reducing poverty and improving rangeland management.  相似文献   

18.
This paper incorporates the indigenous ecological knowledge (IEK) of the Maasai pastoralists and ecological methods to assess effects of grazing and cropping on rangeland biodiversity at macro‐ and micro‐landscape scales in northern Tanzania. The joint surveys with pastoralists identified indicator plant species and their associations with micro‐landscapes and livestock grazing suitability (i.e. for cattle and small ruminant grazing), while traditional calf‐pasture reserves (alalili pl. alalilia) were evaluated for preservation of rangeland biodiversity. The macro‐landscapes comprising the cool high plateau (osupuko pl. isipuki) and montane forest highland (endim) were included in the survey. At micro‐landscape scales, the osupuko was classified into uplands (orkung'u), slopes (andamata) and dry valley bottomlands (ayarata). The micro‐landscapes were assessed in terms of herbaceous plant species and woody species richness and risks of soil erosion. Biodiversity varied at both the macro‐ and micro‐landscape scales and in accordance with the land‐use types. Greater plant species diversity and less erosion risks were found in the pastoral landscapes than in the agro‐pastoral landscapes. The calf‐grazing pastures had greater herbaceous species richness than the non‐calf pastures, which in turn had more woody species. The study concludes that the indigenous systems of landscape classification provides a valuable basis for assessing rangeland biodiversity, which ecologists should incorporate into ecological surveys of the rangelands in East Africa in the future.  相似文献   

19.
Vulnerability Assessment (VA) has numerous management implications, particularly for locating the most vulnerable areas affected by land cover degradation. This study aims to assess and compare the relationship between socioeconomic vulnerability (SEV) and land cover indices (LCIs) in summer rangelands (Natanz county) and winter rangelands (Aran-V-Bidgol county) in Isfahan Province, Iran. To assess the socioeconomic vulnerability index (SEVI), a survey was conducted. Based on the SEVI, summer and winter rangelands were classified and mapped using a combination of fuzzy TOPSIS model and geographic information system (GIS) techniques. Field research was conducted to estimate LCIs, including plant cover, plant yield, litter (dead biomass), sand and gravel, bare soil, and forage production. Finally, the correlations between SEVI and LCIs were verified, and the SEV of winter rangelands and summer rangelands was examined. Results showed the rangelands of Chah Robat, Bidhend, and Tar were the most vulnerable summer rangelands, while the rangelands of Chah Zard, Cheshmeh Sefid, and Kandeh Matin were the most vulnerable winter rangelands. Findings further revealed more LCIs, including total ground cover, the yield of shrubs, and total yield had a significant relationship with SEVI in summer rangelands compared to winter rangelands (yield of annual forbs and total yield). Moreover, there was a significant difference between SEVI, determined by the fuzzy TOPSIS model, in summer and winter rangelands. It can be concluded that while the fuzzy TOPSIS model and GIS can be used to gain a better understanding of VA, the type of rangeland has an impact on how well these techniques can assess the SEV of rangelands.  相似文献   

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