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171.
We examined the changes in forest status and people's livelihoods through building future scenarios for Chilimo Forest in Central Ethiopia where participatory forest management (PFM) is being implemented. Participatory methods were employed to collect data, and a dynamic modeling technique was applied to explore trends over time. By integrating the more quantitative model outputs with qualitative insights, information on forests and livelihoods was summarized and returned to users, both to inform them and get feedback. A scenario of open access without PFM provides higher income benefits in the short term but not over the longer term, as compared to a scenario with PFM. Follow up meetings were organized with national decision makers to explore the possibility of new provisions in the national forest proclamation related to joint community-state ownership of forests. Project implementers must constantly work towards improving short term incentives from PFM, as these may be insufficient to garner support for PFM. Other necessary elements for PFM to succeed include: ensuring active participation of the communities in the process; and, clarifying and harmonizing the rules and regulations at different levels.  相似文献   
172.
Bioregional classifications are used extensively for conservation management and monitoring programs. This study used generalised dissimilarity modelling (GDM) to test the ability of different regional classifications of four groups of aquatic biota to be used as surrogates for each other. Classifications were derived for aquatic macrophytes, macroinvertebrates, freshwater fish and frogs using community-level modelling, or GDM, which relates the biotic assemblage structure with environmental variables. Six regions were defined for each biotic group for the State of New South Wales. Regional classifications differed markedly between the different biotic groups because the environmental drivers that were related to species turnover throughout the region differed among groups. Altitude and rainfall were the strongest drivers of species turnover among the groups. Results suggest that physiographic variables should be incorporated in reserve design and monitoring programs to explicitly address differences in classifications between similar biotic groups.  相似文献   
173.
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park, to help meet the goals of the Natural Resource Challenge—a program to help strengthen natural resource management at national parks. We met this challenge by synthesizing and interpreting natural resource information for planning purposes and we identified information gaps and natural significance of resources. We identified a variety of natural resources at both parks as being globally and/or nationally significant, including large expanses of unfragmented, mixed-mesophytic forests that qualify for wilderness protection, rare plant communities, diverse assemblages of neotropical migratory birds and salamanders, and outstanding aquatic recreational resources. In addition, these parks function, in part, as ecological reserves for plants in and wildlife. With these significant natural resources in mind, we also developed a suite of natural resource management recommendations in light of increasing threats from within and outside park boundaries. We hope that our approach can provide a blueprint for natural resource conservation at publically owned lands.  相似文献   
174.
《Ambio》2022,51(9):1978
Blue Carbon Ecosystems (BCEs) help mitigate and adapt to climate change but their integration into policy, such as Nationally Determined Contributions (NDCs), remains underdeveloped. Most BCE conservation requires community engagement, hence community-scale projects must be nested within the implementation of NDCs without compromising livelihoods or social justice. Thirty-three experts, drawn from academia, project development and policy, each developed ten key questions for consideration on how to achieve this. These questions were distilled into ten themes, ranked in order of importance, giving three broad categories of people, policy & finance, and science & technology. Critical considerations for success include the need for genuine participation by communities, inclusive project governance, integration of local work into national policies and practices, sustaining livelihoods and income (for example through the voluntary carbon market and/or national Payment for Ecosystem Services and other types of financial compensation schemes) and simplification of carbon accounting and verification methodologies to lower barriers to entry.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01723-1.  相似文献   
175.
通过对辽河干流河道险工全面考察、河道险工成因分析以及河道演变分析结果,分别采用马卡维耶夫法、平滩水位法、造床流量保证率法、主汛期月平均流量法对造床流量进行了计算;根据历年主槽平均宽法、经验公式法、造床流量下现状河道水面宽法的计算,同时充分考虑各河段河道特点、上下游协调统一,并为河道的演变发展预留一定空间,综合确定了辽河干流各河段整治宽度;分别针对辽河两岸岸坎-缓坡和陡坡,提出了河道险工综合治理技术,为辽河干流防洪工程体系提供技术支持。  相似文献   
176.
继2009年辽河干流水质COD消灭劣V类后,目前地表水5项主要指标(COD、NH3-N、BOD5、DO、pH)经检测均达到Ⅳ类水质并相对稳定,鱼类已恢复到40种,具有标志性的河刀鱼已重现。辽宁省通过划定辽河保护区,并设立保护区管理局,成立了国内第一个以流域综合管理与行政区域管理相结合的河流管理机构,划区设局为治理保护辽宁人民的母亲河而实施的多目标集成与多措并举提供了体制保障。介绍了辽河划区设局以来实施的主要生态治理技术方法和实践经验,及划区设局在落实“大力推进生态文明建设”的国家战略,实现经济社会和环境协调发展、人与自然和谐相处中的重要作用。  相似文献   
177.
利用高通量测序技术,研究了辽河保护区盘锦段3种类型人工湿地(支流汇入口湿地、坑塘湿地、牛轭湖湿地)底泥和芦苇根际微生物群落结构与分布规律。结果表明: 3种类型人工湿地底泥微生物多样性、丰度和操作分类单元(optical transform units,OTUs)数目均大于芦苇根际微生物,且底泥和芦苇根际微生物多样性受季节变化影响,秋季高于春季;不同类型人工湿地微生物群落结构及分布大致相似,变形菌门(Proteobacteria)为相对丰度最高的优势种,以变形菌门为主的革兰氏阴性菌在人工湿地净化过程中起重要作用;不同类型人工湿地变形菌纲及其相对丰度不同,支流汇入口湿地以α-变形菌纲(Alphaproteobacteria)、δ-变形菌纲(Deltaproteobacteria)和γ-变形菌纲(Gammaproteobacteria)为主;坑塘湿地以γ-变形菌纲和α-变形菌纲为主;牛轭湖湿地中不同纲的微生物分布较均匀。  相似文献   
178.
土壤保持是生态系统提供的调节服务之一,在维持生态安全等方面发挥着重要作用。以辽河保护区为研究对象,基于中国土壤流失方程(CSLE)模型和地理探测器等方法,开展土壤保持功能时空变化及影响因素分析。结果表明:2010—2018年辽河保护区土壤以微度和轻度侵蚀为主,土壤侵蚀量呈降低趋势,土壤侵蚀严重的区域主要位于河流两侧及下段;土壤保持功能不断增强,土壤保持量较高的区域集中在河流上段和中段;土壤保持功能表现出随降水量、高程增加先减少后增加,随坡度和植被覆盖度增加而增加的趋势,在林地—耕地—草地—灌木林梯度上呈递减趋势;土地利用类型是影响辽河保护区土壤保持格局的主导因素;土地利用类型为耕地,降水量为657~735 mm,坡度为35°~68°,高程为-73~-26 m,植被覆盖度为0~0.3时,土壤保持能力最低,坡度和土地利用类型的交互作用对土壤保持能力变化的解释力最强。  相似文献   
179.
The United Kingdom offers some of the finest designed parks and garden landscapes in the world and, whilst there is a wide range of skills and a wealth of literature on the subject, there is little evidence of official effort to systematically record historic sites. This, it is argued, is a factor in the continuing decline of many examples. This paper records an attempt at a comprehensive examination of one county — Cheshire — begun in 1970. The method is described and the results discussed in some detail. Some suggestions are put forward for improvements to official incentives for site owners.  相似文献   
180.
Protecting biodiversity on public lands is difficult, requiring the management of a complex array of factors. This is especially true when the ecosystems in question are affected by, or extend onto, lands outside the boundaries of the protected area. In this article we review recent developments in the cross-boundary management of protected natural resources, such as parks, wildlife reserves, and designated wilderness areas. Five ecological and 11 anthropic techniques have been suggested for use in cross-boundary management. The categories are not mutually exclusive, but each is a distinct and representative approach, suggested by various authors from academic, managerial, and legal professions. The ecological strategies stress the collection of basic data and documentation of trends. The anthropic techniques stress the usefulness of cooperative guidelines and the need to develop a local constituency which supports park goals. However, the situation is complex and the needed strategies are often difficult to implement. Diverse park resources are influenced by events in surrounding lands. The complexity and variability of sources, the ecological systems under protection, and the uncertainty of the effects combine to produce situations for which there are no simple answers. The solution to coexistence of the park and surrounding land depends upon creative techniques and recommendations, many still forthcoming. Ecological, sociological, legal, and economic disciplines as well as the managing agency should all contribute to these recommendations. Platforms for change include legislation, institutional policies, communication, education, management techniques, and ethics.  相似文献   
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