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1.
邓军 《林业调查规划》2023,48(4):207-212
昭通市草地以山地草甸为主,草地生态系统脆弱,管理水平和建设能力不高,退化草地修复难度大。昭通市现有草地面积116 079.33 hm2,其中退化草地面积6 992.10 hm2,占全市草地总面积的6.02%。退化草地主要以轻度退化为主,面积4 221.00 hm2。草地退化的原因包括人为因素、有害生物侵入、生态环境脆弱和气候因素。文章给出近自然修复、人工促进修复、人工草地建植和综合修复等退化草地修复措施,并提出加快草种基地建设、规范草地管理、生态优先、因地制宜等草地修复策略。  相似文献   

2.
美国森林及草原碳管理措施及启示   总被引:1,自引:0,他引:1  
增加陆地生态系统碳汇是应对气候变化的主要策略之一。鉴于森林和草原是陆地生态系统的主体,美国林务部门已将提高其固碳水平作为推行低碳经济和实现可持续发展的一项目标。文中在简述美国森林及草地资源整体现状及其碳储量的基础上,介绍美国林业管理体制并进一步说明其关于森林及草地碳计量及监测数据库,进而说明在上述林业管理体制下美国各部门为应对气候变化指定的一系列关于森林及草地碳汇管理的措施及战略框架,最后总结对我国森林和草原碳管理的启示。  相似文献   

3.
Natural forces and anthropogenic activities greatly alter land cover,deteriorate or alleviate forest frag-mentation and affect biodiversity.Thus land cover and forest fragmentation dynamics have become a focus of concern for natural resource management agencies and biodiversity con-servation communities.However,there are few land cover datasets and forest fragmentation information available for the Dhorpatan Hunting Reserve (DHR) of Nepal to develop targeted biodiversity conservation plans.In this study,these gaps were filled by characterizing land cover and forest frag-mentation trends in the DHR.Using five Landsat images between 1993 and 2018,a support vector machine algorithm was applied to classify six land cover classes:forest,grass-lands,barren lands,agricultural and built-up areas,water bodies,and snow and glaciers.Subsequently,two landscape process models and four landscape metrics were used to depict the forest fragmentation situations.Results showed that forest cover increased from 39.4% in 1993 to 39.8% in 2018.Conversely,grasslands decreased from 38.2% in 1993 to 36.9% in 2018.The forest shrinkage was responsible for forest loss during the period,suggesting that the loss of for-est cover reduced the connectivity between forest and non-forested areas.Expansion was the dominant component of the forest restoration process,implying that it avoided the occurrence of isolated forests.The maximum value of edge density and perimeter area fractal dimension metrics and the minimum value of aggregation index were observed in 2011,revealing that forests in this year were most fragmented.These specific observations from the current analysis can help local authorities and local communities,who are highly dependent on forest resources,to better develop local forest management and biodiversity conservation plans.  相似文献   

4.
目前,草地研究成为国际生态学与环境科学研究的热点问题之一。3S技术的发展为草地研究提供了新的方法和强有力的技术支持。文章主要论述了3S技术在草地资源调查、草地景观变化、草地资源管理等方面的应用概况;并概述了3S技术在草地研究应用中存在的主要问题和解决方案以及发展前景。提出应加大3S技术集成的深度,加强在草地保护及资源管理等方面的应用,对草地资源信息进行分析处理并延伸到研究草地空间规划和决策方面,以便科学利用和管理草地资源。  相似文献   

5.
乌拉圭拥有丰富的草原资源和发达的畜牧业,草原保护和治理工作在近年取得快速进展,其先进的治理方法和保护措施具有重要参考价值。文中概述乌拉圭草原现状,总结乌拉圭草原生态保护与治理政策及机制;分析我国草原保护及治理工作面临的挑战,包括草原退化形势严峻,畜牧模式存在缺陷,矿业对草原形成威胁,牧民发展生态保护意识淡薄等;在此基础上,提出乌拉圭对我国草原保护的启示:如积极采取多部门联合管理模式、优化轮牧模式、推进草原管理能力建设及宣传工作、加大对以草原为主的国家公园及国家保护区的投资和建设力度、在草原保护中推广高新技术。  相似文献   

6.
With or without human intervention, animals are important components of grassland and forest ecosystems. When settlers occupy and cultivate land, they invariably bring animals with them. Livestock integrated in the production system convert crop residues and weeds into valuable products while most plant nutrients are retained. As animal feed, Imperata has low nutritional value, especially with advancing maturity. Supplemental feeding of ruminants with urea-molasses-mineral blocks or introduction of fodder species, especially legumes, have significantly improved production under smallholder farm systems. Fodder species for fallow improvement, modified alley cropping or hedgerow systems, and plantations integrating livestock production, all hold promise for future use of Imperata grasslands. Diversified systems may help settlers reach self-sufficiency while increasing the sustainability of the system. Research and development interventions towards improved livestock productivity in smallholder farms may have low economic but high social benefit. These benefits are especially attainable if the farm families participate in the design and implementation of innovations. Security of land tenure, provision of credit, and mechanisms marketing of produce are issues that need to be addressed in more innovative ways.  相似文献   

7.
Summary

The commercial harvest of wild edible forest mushrooms has increased dramatically in the Pacific Northwest United States during the last decade, creating public and managerial concerns about potential over-harvesting. These concerns have prompted Federal land m anagement agencies and research organizations to undertake a variety of research projects addressing the ecological impacts and long-term sustainability of widespread harvesting. This article lists and briefly describes 25 ongoing research projects investigating the three most important forest mushroom genera of commerce; matsutake, morels, and chanterelles. We finish by describing future Federal directions in regional research and monitoring designed to ensure sustainable harvests through long-term cooperative monitoring involving multiple stakeholders, especially interested publics.  相似文献   

8.
Abstract

With the new emphasis in land management agencies (particularly the USDA Forest Service) on ecosystem management, new attention is being paid to measurements of biological diversity (biodiversity). Forest managers faced with incorporating the maintenance of biodiversity into their analyses, plans, and decisions need reliable, quantitative biodiversity measures. Deciding which measures to use requires land managers to understand why biodiversity is valued, which components of diversity are of most value, and how to measure these components feasibly. In this paper, the values associated with biodiversity and the principal indices available to forest managers are reviewed. Attention is drawn to the differing emphases of biodiversity indices-species richness, heterogeneity, and evenness-and to how diese differences address different values. Potential applications for these indices in forest management plans-including ways to use habitat models to approximate biodiversity-are also discussed.  相似文献   

9.
通过草原综合植被盖度监测,主要调查草原样地基本特征、地理位置(经纬度)、主要植物种类、样地综合植被盖度等要素,综合测算广西草原综合植被盖度。结果表明,本次调查广西共布设监测样地812个,测算出草原综合植被盖度为82.76%,较2019年提高0.93%,其中,热性草丛类、热性灌草丛类、暖性灌草丛类植物的综合植被盖度分别为84.11%、82.88%、89.00%。同时对关系草原综合植被盖度变化原因及存在问题进行分析,提出相关建议,以期为广西全面建成小康社会统计监测指标体系和广西绿色发展指标体系提供重要基础指标数据。  相似文献   

10.
鄂托克旗土地利用动态变化及其影响要素分析   总被引:1,自引:0,他引:1  
在RS与GIS技术的支持下,利用1991、2000和2007年三期TM影像,对鄂托克旗1991-2007年的土地利用动态变化特征及其影响要素进行分析。结果表明,土地利用最重要的转化方向有:1991-2000年耕地向草地、未利用地和城乡、工矿用地的转化;草地、水域向未利用地的转化;2000-2007年未利用地向草地、水域和耕地的转化;耕地向林地和草地的转化;城乡、工矿居民点用地向草地和林地的转化。反映鄂托克旗既有退耕还林还草、积极治理沙漠的事实,又有毁草开垦荒地的现实。随着耕地和未利用土地的减少,林地和草地面积增加,说明当地环境的改善已取得了成效。  相似文献   

11.
Abstract

It is important to analyze cross-sectoral policy linkages and to quantify their effects by using the system of integrated environmental and economic accounting in order to ensure effective integration of forestry into national development. This paper reviews relevant policy linkages in the forestry sector, policy applications of forestry accounts, and challenges to their implementation. It argues for the need to develop regional or local accounting methods providing social, environmental, and economic data to allow assessment of the combined impacts of different public policies. It emphasizes the urgency of strengthening the management capacity of public agencies in dealing with complex policy networks addressing sustainable and multifunctional forest management.  相似文献   

12.
Abstract

This paper describes the development of two community-managed protected areas in the Mexican state of Oaxaca. Specifically, it focuses on the diverse factors that have allowed the community-based reserves initiatives to unfold and analyzes some of the social-institutional structures that communities have constructed for autochthonous management of land and resources. The information for this paper was gathered through institutional analysis employing semi-structured, open-ended interviews with administrators, manager-practitioners, local farmers, and community representatives from the Chimalapas and Sierra Juárez regions of Oaxaca. The results of this study support the conclusion that, given strong social institutions, local communities can successfully form management partnerships for forest conservation and autochthonous development.  相似文献   

13.
我国将生态文明建设纳入"五位一体"总体布局,草原成为生态文明建设的主战场之一.目前我国草原主要面临火灾、旱灾、鼠虫害等风险,开展草原保险可以弥补上述风险造成的损失.文中介绍世界上较为完备的美国牧草保险业发展,尤其是降雨指数保险的基本情况、运作模式及主要内容;在此基础上,对我国草原保险机制的构建提出了引入草原降雨指数保险...  相似文献   

14.

Agroforestry is a sustainable land management system recognized worldwide but not implemented in a extensive form in temperate and developed countries. Agroforestry has been promoted in the last decades at global level as it provides more efficient and sustainable farming systems. This review aims at summarizing the main research findings explaining why agroforestry is a sustainable land management that fulfils and is affected by different Global, Pan-European and European policies as well as how innovation is currently fostered in Europe, therefore linking research, policy and innovation. This review specially targets researchers and policy makers working in integrated land systems. There is a global and European recognition of the role that agroforestry can play to provide products but also to deliver highly important ecosystem services. However, the promotion of agroforestry practices at European level is still not well addressed by the Common Agricultural Policy. The clear identification of agroforestry practices, the link of management plans to establish agroforestry pursuing a final eligible tree density for the Pillar I payments should be addressed as initial steps to foster agroforestry in Europe. There is a lack of knowledge transfer that promotes agroforestry at field level, which should be approached by using stakeholder integration within the policy development as it is currently done by the EIP-Agri.

  相似文献   

15.
Fire is an important factor in the Imperata grassland ecosystem. It prevents or slows down the natural succession to shrubs and/or secondary forest vegetation and is a major threat to (agro)forestry options for Imperata grassland rehabilitation. Forest fires can also be a primary cause of the extension of Imperata grasslands. In this review an attempt is made to integrate biophysical and socioeconomic aspects of the causation of fires in a conceptual model. Fire effects on vegetation are examined. The management options at the level of a farmer, a village community and a national government are analyzed.  相似文献   

16.
Low intensity grazing with large herbivores is increasingly used to steer the development of mosaic landscapes (including wood-pastures) and woodland expansion on former agricultural land. We studied the establishment and early growth pattern of woody species in grasslands (formerly used for high intensity summer cattle grazing) in which a low intensity-grazing regime was set up between 4 and 11 years ago. We tested whether the developing vegetation patches, consisting of tall herbs and scrub, influenced this pattern. Further, we investigated if increased susceptibility to trampling disturbance by large herbivores on wet soils in floodplains influenced sapling establishment.Formerly intensively used grasslands were studied at six sites, four in floodplains and two in interfluvial zones on nutrient rich, heavy soils. In total, we sampled 141 plots with grassland, tall herb or scrub vegetation and recorded individuals of established tree and shrub species, their height, diameter, browsing damage and distance to potential seed sources. In the floodplains, we recorded soil disturbance by large herbivores (hoofprints) in wet and moist soils.Sapling frequencies, with Fraxinus excelsior as the most common species (>50% of all individuals), were two to three times higher in tall herb and scrub patches compared to grassland. Only the spiny Crataegus monogyna established in higher frequencies in grassland plots. In floodplains, we found two to three times more established woody saplings in wet tall herb plots, compared to moist and wet grassland plots and moist tall herb plots.Browsing reduced sapling height in grassland and tall herb patches. Only in scrub patches did average height (±2.5 m) reach above the browse line. We found 30–70% less browsing damage to saplings in scrub compared to damage in grassland and tall herb plots. In particular, damage to the apical shoot was strongly reduced.Our findings show that tree establishment occurs in spatial association with non-grassland patches that offer protection against browsing. Fast growing spiny shrubs like Rubus sp. offer protection for palatable saplings, allowing establishment and growing out beyond the browse line. Alternatively, increased establishment occurs in wet tall herb patches, where soil disturbance by moderate trampling favours germination and, subsequently, saplings are protected at least temporarily against browsing by unpalatable tall herbs.  相似文献   

17.
文章利用RS和GIS的空间分析技术,以TM遥感影像为主要信息源,通过目视解译的方法提取研究区土地利用动态变化数据,结合现地调查进行区域土地利用动态变化分析。研究结果表明:研究区不同土地利用类型之间转换明显,其中,以耕地、草地面积减少,林地、灌木林地、居民地和工矿用地增加为主。土地利用类型变化主要受经济因素影响,国家投入增加和地方经济的发展是土地利用变换的主要原因。  相似文献   

18.

Current Indonesian beef production only meets 45% of local demand. Increasing local beef production through integration of cattle production in pre-existing oil palm plantations is a possible solution to meeting this shortfall. The oil palm understorey provides feed, alleviating the need to convert additional land to agriculture. Smallholders are important contributors to both Indonesian cattle and palm oil production. This case study research seeks to understand key aspects of smallholder cattle management in palm oil production areas, to highlight opportunities and barriers to cattle integration. Thirty-nine smallholder cattle farmers from four villages in South Kalimantan were individually interviewed. The lack of alternative feed sources was the major driver towards the adoption of cattle production using oil palm understorey as feed. Cattle grazing was uncontrolled due to labour shortages and occurred in individually owned and ‘plasma’ plantations, with cattle penned at night where possible to avoid theft. Arrangements on land access and use between stakeholders are needed for systematic cattle grazing and to control cattle theft.

  相似文献   

19.
Abstract

Agricultural expansion by smallholder producers has been identified by management agencies as one of the main threats to the ecological integrity of La Amistad Biosphere Reserve, in Panama and Costa Rica. Promotion of cacao agroforestry has been proposed as a way to reduce the need for farmers to clear new land within the reserve. In order to realize this goal, the larger cultural, economic, and political forces that motivate agricultural expansion need to be examined, looking beyond the smallholder practices that are the immediately apparent causes of ecological degradation. The four main assumptions behind the proposal to promote smallholder cacao production in the buffer zone are explored: (1) cacao agroforestry is an ecologically benign agricultural system; (2) if cacao production were more financially viable, ecologically degrading activities, such as cattle grazing, would decrease; (3) migrants from other areas are primarily responsible for clearing land on the eastern side of the park; and (4) direct intervention at the smallholder level is the most effective means of preventing agricultural expansion. Our analysis demonstrates that while cacao agroforestry is an ecologically appropriate production system for the buffer zone of the park, price and production stabilization is important for assuring adoption by smallholders. We also suggest that both indigenous and migrant groups are responsible clearing forest for agriculture and that a more useful distinction for managers to make is between clearing enacted as part of sustainable vs. unsustainable management regimes. Finally, we recommend that the impact to the biosphere reserve caused by large-scale cattle and banana production not be overlooked.  相似文献   

20.
甘肃民勤连古城国家级自然保护区面积389882.5hm^2,位于石羊河流域下游民勤绿洲的外围,直接保护着民勤一武威绿洲的生存与发展,保护荒漠植物是其最主要的任务之一。保护区植物种类相对贫乏,共有种子植物64科227属474种(包括变种及栽培种),还受到水环境恶化、植被退化、土地沙化以及人为活动等因素的威胁,建议采取加强宣传教育、提高环保意识,完善政策法规、依法管理保护,遵从自然规律、科学规划经营,加强能力建设、发展社区经济的保护对策。  相似文献   

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