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1.
Many bird species respond to forestry, even at moderate intensities. In New Brunswick, Canada, the Brown Creeper exhibits a negative, threshold response to harvesting intensity. This study aimed to determine whether (a) the threshold found in Brown Creeper occurrence is lower than eventual thresholds in its nesting requirements, and whether (b) the conservation of this species could be achieved through moderate-intensity harvest systems. Creepers are particularly sensitive to forestry because they nest on snags with peeling bark and they mainly forage on large-diameter trees. In northern hardwood stands, we compared habitat structure at local- (r = 80 m) and neighbourhood-scales (r = 250 m) around nest sites and sites not used by creepers. Over two years, we found 76 nests, 66 of which were paired with unused sites for comparison. At the local scale, densities of trees 30 cm dbh and snags 10 cm dbh, and the probability of presence of potential nest sites were significantly higher near nests than at sites where no creepers were detected. At the neighbourhood scale, the area of untreated mature forest was significantly higher around nests. Variance decomposition indicated that habitat variables at the local scale accounted for the majority of explained variation in nest site selection. We also found significant thresholds in the densities of large trees (127/ha) and snags (56/ha), and in the area of mature forest (10.4 ha). The conservation of breeding populations of Brown Creepers may thus require densities of large trees nearly twice as high as those associated with its probability of presence. Such a target seems to be incompatible even with moderate-intensity harvesting.  相似文献   

2.
 通过对水泥工程的类型、组成、占地以及施工和生产工艺、土石方量及弃渣的分析,总结出水泥工程在建设与生产过程中的水土流失特点,水泥工程在建设期间的水土流失重点区域是厂区,而在生产运行期则是石灰石和黏土矿,此外在水泥生产厂区还会产生大量的粉尘。水泥工程除了应遵循"生产建设项目水土保持准入条件通用条款"中的条件外,对照涉及水泥产业的法律、法规、规范、政策、标准、发展纲要和行业发展规划,提出了水泥工程项目的否决、限批和缓批的13条水土保持准入条件。根据水土保持新国标和有关法规的规定,结合典型案例分析,提出须修正主体设计的5项准入条件和须修改水土保持方案的4项准入条件。  相似文献   

3.
国外农作物秸秆利用政策法规综述及其经验启示   总被引:6,自引:9,他引:6  
发达国家在农作物秸秆利用方面取得丰富的经验和研究进展。中国的秸秆利用管理政策和法规尚不完善。分析国外农作物秸秆利用政策和法规,总结其成功经验,以资中国借鉴。发达国家秸秆利用方式以秸秆还田循环利用为主。为了实现秸秆资源的充分利用,许多发达国家出台了有针对性的政策与法规。国外秸秆利用政策主要集中在目标政策、投资扶持政策(财政政策)、税收与信贷优惠政策、政策激励机制4个方面。国外有关秸秆利用的法规主要包括农业类法规和能源类法规2大类。借鉴国外先进经验,提出了完善中国秸秆利用政策与法规的建议:一是明确秸秆利用的主导方式和目标,二是加大政府投资扶持力度,三是制定并实施税收和信贷优惠政策,四是建立政策激励机制,五是完善和制定有关秸秆利用的法规和条例。  相似文献   

4.
北方土石山区生态修复与水源涵养研究进展与展望   总被引:2,自引:1,他引:1  
生态文明建设与生态环境保护是人与自然和谐相处与和谐共生的必然要求,是实现经济社会可持续发展和人民群众对美好生态环境的现实需要、建设美丽中国的实际需要。针对太行山区生态系统严重退化、环境容量与承载力低下、基础设施薄弱、自然条件与资源禀赋较差、贫困程度较深等问题,中国科学院遗传与发育生物学研究所农业资源研究中心从20世纪80年代开始在太行山中段东坡的低山丘陵区进行生态修复与可持续发展的研究,通过30年的研究实践,提出并建立了较为完整的北方土石山区生态修复治理体系,为山区生态文明建设和生态环境保护,以及扶贫攻坚和社会经济可持续发展提供了经验与示范。本文通过30年研究历程回顾、研究与展望,总结了土石山区生态修复与水源涵养的进展与展望。太行山林业生态工程建设主要经历了3个阶段:一是研究初始阶段(1986—1996年),确定了退化山地生态系统恢复的途径与技术理论,建立了以水土富集为中心的林业生态工程。二是提升发展阶段(1997—2007年),这一阶段主要是研究了影响退化山地生态系统恢复与重建的关键因子与影响机制,并提出了有效的技术措施与解决方案。具体说来,在径流林业研究方面,研制出了太行山水土富集工程带间距计算公式;在降水资源转化与水分运移规律研究方面,明晰了岩土二元结构体的降水-土壤水-裂隙水的基本补给路径,揭示了岩土界面"优先流"与裂隙网络"优先流"的运行转化规律,阐明了浅层风化裂隙岩体渗流的动态变化特征及对植被耗水过程的响应关系;在降水资源调控利用研究方面,研制出了生物集雨新材料、营养调理剂和生物集雨面建造施工工艺。三是全面创新阶段(2008年—),重点探讨了山区生态产业开发与区域可持续发展问题,研发了经济林土壤扩蓄增容技术、石质山地困难立地造林技术、经济林生态隔离带调控技术、京津风沙源治理工程区沙产业开发技术,以及林下经济、循环经济、生态旅游等生态产业化技术体系。下一步将在目前研究的基础上,向人口密度较大、人类活动频繁的雄安新区上游山区扩展,重点开展以国土绿化、景观建设、水源涵养、水土流失治理、污染防治为主要内容的山水林田湖草一体化生态环境与气候变化监测,研究现代干扰条件下山地灌丛生态系统向森林生态系统的演替过程及主要驱动因素,山地水旱灾害形成机制、降水资源调控与水源涵养,以及以产业生态化和生态产业化为主体的山地生态经济体系,为构建结构稳定、功能完善的京津冀生态环境支撑体系与水源涵养功能体系提供科学依据和技术支撑,为山地生态系统经营管理,实现其生产、生态功能和系统稳定性提供科学参考。  相似文献   

5.
 港口码头、独立大桥与隧道、海堤防等涉水交通工程占地性质多为永久占地,土地的原有功能完全转变;由于涉河涉水兴建此类工程,其环境敏感性强,引发的水土流失危害及环境影响较为直接;土石方挖填量大,施工过程中发生的水土流失直接进入江河湖海。根据我国有关法规、政策、规划、标准等规定,结合涉水交通工程项目的特点,提出了此类项目准入、限批、缓批的主要条件,从项目水土保持准入方面提出了修正完善主体设计、修改完善水土保持方案后再报批的条件,以及水土保持方案准入排序意见。  相似文献   

6.
Manilkara hexandra (Roxb.) Dubard (Khirni) is a socio-economically important fruit and nut species of tribal population of tropical deciduous forests of western and central India. Survey and collection missions were undertaken to study the extent of variability and socio-economic importance of Khirni germplasm in diversity rich areas of Rajasthan, Gujarat, Madhya Pradesh and Maharashtra. A total of 99 accessions of this important tree species were collected from surveyed regions, of which 47 diverse accessions were selected for morphological characterization showing wide range of variation in agro-morphological traits. During the survey, sizable variability in morphological characters and high socio-economic potential of Khirni was recorded. Bark, fresh fruits and extracted seeds have high nutritional and medicinal value. Tree provides substantial livelihood support to local inhabitants as collected fresh fruits from natural populations fetch good price in local markets. Besides livelihood support species, M. hexandra contributes in the nutritional security of the women and children of this area by fulfilling the need of micronutrients and vitamin A. Due to the high market demand of fresh fruits and seeds and without any organized cultivation, pressure on natural wild populations is severely building up since last several decades and therefore, the genetic variability of this species is now facing a great threat and need immediate complementary conservation efforts. Based on higher diversity index and natural population size of this species six in situ conservation sites have been suggested for dynamic conservation in western and central Indian states and 60 accessions have been successfully cryostored.  相似文献   

7.
The interdigitation of the Nearartic and Neotropical biogeographic zones in the Transvolcanic Belt (TVB) of central Mexico provides the region with high faunal richness and endemicity. Biodiversity conservation in the TVB must accommodate the region’s human population of more than 40 million. The current study presents conservation plans for the TVB intended to protect 99 non-volant mammal species while minimizing the impact on the human population. A rarity-complementarity algorithm was used to select a conservation area network (CAN) from sites with untransformed vegetation to represent 10% of each species’ habitat. In addition, a new method was developed for augmenting the connectivity of CANs using graph theory. External sites were assigned quality scores based on the frequency with which they were selected at different targets of representation for species. Graph algorithms identified the highest-quality sites needed to link all conservation areas in an economical manner. These connectivity areas can facilitate migration or egress of biota in the event of local environmental stress. The network initialized with existing protected areas occupied 9.13% of the TVB, whereas the network built from scratch occupied 6.02%. In both cases, an additional area of only about 1.5% of the region was required to link all conservation areas in the network. Finally, a multiple criterion synchronization technique was used to select those connected networks which minimized both total area and human population impact.  相似文献   

8.
The future food supply of all societies depends on the exploitation of genetic recombination and allelic diversity for crop improvement, and many of the world's farmers depend directly on the harvests of the genetic diversity they sow for food and fodder as well as the next season's seed. On farm conservation is an important component of the global strategy to conserve crop genetic resources, though the structure of costs and benefits from on farm conservation differ from those associated with ex situ conservation in gene banks. A fundamental problem that affects the design of policies to encourage on farm conservation is that crop genetic diversity is an impure public good, meaning that it has both private and public economic attributes. This concept is defined and made operational in order to assist practitioners in identifying (1) least-cost sites for on farm conservation (2) the types of policy instruments that might be appropriate for supporting conservation once a site has been located. Published findings regarding prospects for on farm conservation as economies develop are summarized and empirical examples of suitable policies to support farmers' decisions are placed in the context of economics principles.  相似文献   

9.
The Walenboscomplex is one of the few remaining natural sites of the Hageland, a mainly agricultural region in central Belgium. The vegetation characteristic of the area requires periodic management, protection on its own not being sufficient. A review of the legislation available to protect natural areas in Belgium is given. Because of damage by hunting activities, the threat of industrial development and water abstraction, together with the need for conservation management, the Walenboscomplex can only be saved by its establishment as a nature reserve by government decree.  相似文献   

10.
陕西省能源开发水土保持补偿法律制度研究   总被引:1,自引:0,他引:1  
在介绍陕西省实行能源开发水土保持补偿的背景、界定水土保持补偿的内涵与外延的基础上,重点分析了陕西省能源开发水土保持补偿法律制度的现状及所存在的水土保持补偿机制的法律地位尚未全面确立、现行的补偿标准偏低、水土保持补偿的约束力和强制性不够等问题。针对存在的问题,提出了陕西省要尽快从法律层面建立与完善能源开发水土保持补偿机制、修订地方法规和合理确定水土保持补偿收费标准、依托法治建立和完善能源开发水土保持补偿费征收制度、提高水土保持补偿法律法规的约束力和强制性、努力形成水土保持补偿的完整法律体系的建议。  相似文献   

11.
机场工程水土保持准入条件   总被引:2,自引:0,他引:2  
 机场建设项目占用土地大多为永久占地,对原地貌的扰动和土石方量较大,施工工期长,造成的水土流失和环境影响较大。在分析机场工程组成及其水土流失特点、占用资源特征、环境影响程度的基础上,根据有关法律法规、产业政策、行业规划、技术标准等规定和要求,提出机场建设项目水土保持准入的4项条件和机场项目水土保持方案准入的5项条件。  相似文献   

12.
黑龙江、吉林两省 ,水土保持生态建设抓得好、抓得实 ,以小流域为重点的综合治理坚持高标准、高效益。两省明确了水土保持宣传周、宣传月 ,利用各种形式宣传水土保持法律法规、治理成果 ,使水保政策法规深入人心。把查处违法案件作为加强水土保持工作的突破口来抓 ,收到了处理一起、教育一片、带动一片的良好效果。加大水保科研投入 ,不断提高水保科技含量。以鸡西市、通化市为代表的水保城市试点 ,推进了城市水土保持生态环境建设。对中央财政专项项目实行动态管理 ,确保资金用在“刀刃”上。介绍了具体的做法和经验  相似文献   

13.
Conservation biology is mainly interested in prioritizing sites on the basis of their high biodiversity. Although species richness is a commonly used criterion, it does not take other crucial aspects of identifying conservation priority sites into account, such as rarity or taxonomic distinctness. Additionally, management efforts are usually focused on the conservation of a small number of species, mainly vertebrates. However, the biodiversity patterns of these faunal groups and the main factors which determine them cannot be generalized to other faunal groups (e.g. aquatic invertebrates). Therefore, the objectives of the present study are: (1) to compare the response of 11 biodiversity metrics in order to know which ones are redundant, (2) to identify key environmental factors for biodiversity, and (3) to find out whether sites with high biodiversity values also have a good habitat condition and high protection status. The study was done at assemblage level (crustaceans and insects) in 91 wetlands in the NE Iberian Peninsula. Regression tree models were used to identify the key factors influencing biodiversity, including water, wetland and landscape characteristics as explanatory variables. Generalized Linear models were used to establish the relationship between biodiversity metrics and protection status and habitat condition. The results obtained by the two sampled seasons were compared. Conductivity was the main factor influencing biodiversity metrics. Positive significant relationships were found between some biodiversity metrics and wetland habitat condition, whereas there were none for protection status, indicating the inadequacy of conservation policies to protect wetland aquatic invertebrate biodiversity.  相似文献   

14.
The growing concern about the profound influence of human activities on marine ecosystems has been the driving force behind the creation of marine reserves in the last few decades. With almost 4200 km of coastline, Chile has not been the exception to this trend. A set of conservation priority sites has recently been proposed by the Chilean government to expand the current marine reserve network. In this study, we used the most comprehensive information currently available on the distribution of 2513 marine species in Chile to assess the efficiency of the existing system of marine protected areas (MPA) and the conservation priority sites identified by the government. Additionally, we evaluated the vulnerability of the reserve network selected with respect to threatening human activities. Our results show that both the existing protected areas and the proposed priority sites are relatively effective at protecting Chilean marine biodiversity. However, the majority of the species that are not represented within the existing or projected MPA network have very restricted distributions and are, therefore, of high conservation concern. To cover all species requires a network of 35 MPAs (46% of the total number of planning units). Many of the sites identified as irreplaceable present conflict with one or more human activities, particularly in the central region of the country. This study emphasizes the need for a systematic conservation planning approach to maximize the representation of species and prioritize those areas where conflicts between marine biodiversity conservation and human activities may occur.  相似文献   

15.
An effective nature reserve network design should reflect the ecological requirements of target species, while simultaneously considering costs. In this study, we propose a design method that considers the ecological role of the spatial arrangement of reserve sites in relation to the long-term persistence of metapopulations of the target species. We apply our design method to an amphibian metapopulation, which illustrates how varying the emphasis on the importance of design factors can affect estimated metapopulation persistence. Comparisons among reserve design methods show that considering the ecological function, rather than generic spatial rules, of the spatial location of reserve sites may be more likely to support species survival. A piecemeal treatment or mechanistic application of spatial rules in reserve design may be subject to the risk of not producing the most effective reserve network, and in some cases may even compromise the conservation objective which could be achieved otherwise.  相似文献   

16.
[目的]为了加强水土流失严重区,生态脆弱地区,水土流失重点预防和重点治理区,崩塌、滑坡危险区和泥石流易发区等特定区域生产建设项目水土保持的分类管理。[方法]通过对特定区域的水土流失特点及水土流失防治对策,结合有关水土保持法法律、法规和技术标准等拟定水土保持的分类管理要求。[结果]提出了特定区域生产建设项目水土流失防治技术要求。主要包括:提高水土流失防治标准和水土保持工程等级,严格控制地表扰动范围,最大限度减轻对区域水土流失影响等。[结论]不同区域生产建设项目水土流失防治应该执行特定的防治标准等级、防治工程设计标准等级和水土保持措施综合配置及相应的技术要求。  相似文献   

17.
Marine protected area (MPA) networks designed without consideration of the interests of local communities are likely to fail. However, in many regions where conservation action is needed most urgently, socioeconomic data are not available at spatial scales relevant to conservation planning. In the Philippines, the primary stakeholders relevant to conservation efforts in coastal waters are small-scale fishers. Unlike commercial fisheries, no logbook data are kept to record fishers’ spatial effort and usage patterns. We investigated the effects of including different surrogates for small-scale fishing effort in the systematic design of an MPA network for Siquijor Province. We compared a reserve selection scenario in which socioeconomic data were not considered with four different surrogates for fishing effort and with empirical data on the spatial distribution of fishing effort collected through interviews. We assumed that minimising opportunity costs to fishers would increase the likelihood that they would support and comply with MPA implementation, resulting in more effective conservation. Surrogates modelled on the number of fishers or boats in each community consistently outperformed those based on population census data. However, none of the surrogates we tested were able to accurately predict fine-scale resource use patterns. Whilst socioeconomic surrogates may be able to assist conservation planners to identify regional-scale opportunities where conservation objectives may be met more easily, they cannot act as a shortcut for comprehensive consultation with communities, which will be required to identify actual sites for MPA implementation.  相似文献   

18.
公路铁路工程水土保持准入条件   总被引:1,自引:0,他引:1       下载免费PDF全文
 公路铁路工程均为建设类线型工程,与其他开发建设项目相比,具有战线长、跨越地貌类型多、占地面积多且多为永久占地、动用土石方工程量大、沿线取(弃)土场多的建设特点。通过对照法律、法规、标准、规划等相关资料,提出公路铁路工程项目共用的水土保持准入条件4条、公路铁路工程项目分别采用的水土保持特殊准入条件各1条,公路铁路共用限批条件3条、公路特殊的限批条件1条,水土保持方案须修正主体工程设计后再报批条件4条、须修改完善水土保持方案后再报批条件3条,并提出水土保持优先审批、暂缓审批的10条建议。  相似文献   

19.
Reedbeds have high conservation value in Europe. In southern France, they are the major breeding habitat of five passerine species. Yet, habitat management is done primarily by water control to serve socio-economic rather than conservation interests, because we lack information on the species' ecological requirements. Determinants of passerine abundance were assessed through a comparative analysis of water regime, plant structure, and arthropod (food) distribution at 12 sites consisting of at least 10 ha of marsh densely covered with common reed (Phragmites australis). Overall bird abundance estimated through standardised mist netting was positively correlated with food availability (sweep-netted arthropods weighted by their occurrence in birds' diet), which was in turn negatively correlated with duration of ground dryness between June and December. Abundance of four of the five bird species was associated with specific vegetation parameters (reed diameter, dry reed density, growing reed height, etc.), which could be associated with particular management practices, especially with regard to water levels and salinity. Potential impact of socio-economic activities through their water management is addressed, as well as possible ways to minimise these impacts.  相似文献   

20.
Changes in all woodlands within study areas in Northamptonshire, Lincolnshire and Cambridgeshire between 1946 and 1972/73 are enumerated using air photographs and ground survey. These conformed to national, long-term trends from coppice to high forest management and from native to introduced species. Differences between areas are ascribed to variation in the relative importance of forestry and agriculture. The effects on wildlife and scientific interest were assessed against criteria developed from an historical approach to woodland conservation, and by examining the area of woodland available to species requiring woodland of particular physiognomy and origin. Modern forestry as an alternative to agriculture has probably favoured species which are good colonisers, catholic in their woodland requirements, and/or require conifers. Species which are poor colonisers and/or require broadleaf woodland have probably declined most in those areas where reforestation has been extensive, and have survived best where forestry has been insignificant in relation to agriculture. Since these are the species most highly valued for conservation and because they are correlated in their occurence with features of special scientific interest, modern forestry is judged to have been relatively harmful to conservation values in Eastern England during the study period. However, the net long-term effects of modern forestry on woodland conservation values are difficult to predict, for this depends partly on the fate of woods in areas devoted mainly to agriculture, which are unlikely to be managed by modern forestry methods.  相似文献   

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