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71.
Ecological regionalization is a base for rational management and sustainable utilization of ecosystems and natural resources. It can provide a scientific basis for constructing healthy ecological environments and making policies of environmental management. In this paper, based on synthetic analysis of the characteristics of the ecology and environments of China, the principles of ecological regionalization are discussed, and indices and nomenclature of ecological regionalization are proposed. The ecoregions on a national scale are divided. The results show that there are 3 domains, 13 ecoregions and 57 ecodistricts. The present scheme can be used as a framework for ecosystem assessment and management. Based on the ecoregions, measurements of management for forest, grassland, agriculture and wetland ecosystems are recommended. The experience and information can be used within and beyond the national scale for land-use planning, biodiversity conservation and ecosystem restoration.  相似文献   
72.
China has the fifth largest forest area in the world and any change in China's forestry development will have inevitable impacts on global ecological sustainability. China has undergone excessive logging of natural forests and also made tremendous efforts in afforestation during the past half century. China's forestry is now going through a variety of transitions and several forestry programs have been implemented to drive forestry transitions. The goal of these actions is to protect ecological services of forests and sustain China's forestry development. These forestry programs are spatially sophisticated and cannot be successfully implemented without accurate and transparent forest/forestry information. A variety of digital technologies, including forest modeling, remote sensing, geographic information systems, global positioning systems, and visualization, have been applied in handling diverse information in China's forestry. Digital forestry is not just a theoretical concept in China. Our digital forestry experience in northeast China suggests that digital technology is both usable and useful in China's forestry development. Digital technology is playing an important interactive role in China's top-down forestry administration system. The analog-to-digital transition in technology is expected to lead to the success of forestry programs and forestry transitions in China.  相似文献   
73.
The Yellow River Delta region in China is a land area of 1,200,000 ha with rich natural resources. Adverse environmental conditions, such as low rainfall and high salinity, promote the dominance of black locust trees for afforestation. With the increase of CO2 in the atmosphere, this forest and others throughout the world have become valued for their ability to sequester and store carbon. Forests store carbon in aboveground biomass (i.e. trees), belowground biomass (i.e. roots), soils and standing litter crop (i.e. forest floor and coarse woody debris). There are well-developed methods to sample forest ecosystems, including tree inventories that are used to quantify carbon in aboveground tree biomass. Such inventories are used to estimate the types of roundwood products removed from the forest during harvesting. Based on standard plot inventories and stem analyses, carbon sequestration estimates of trees were 222.41 t ha?1 for the Yellow River Delta region accounted for 67.12% of the whole forest. Similarly, carbon storage by herbaceous matter and soil was 0.50 and 50.34 t ha?1, respectively. The results suggest that carbon sequestration in the forest ecosystem was performed by most of the forest, which plays an increasingly important role in sequestering carbon as the stand grows.  相似文献   
74.
This article presents a system dynamics (SD) method to examine the problem of forest degradation. The model developed takes a system-oriented view of forest management, embracing both social and biophysical factors affecting deforestation. Social factors examined are socio-economic variables or elements that influence behaviour and decision-making choices at the household level. Biophysical factors are four sub-components that are considered major land uses namely, the paddy field component, rattan plantations, coffee plantations and forest stands. The model was applied in a case study located in Pasir District of East Kalimantan, Indonesia. The site covers an area that includes a protected forest and a privately allocated timber license concession. Three village communities are examined in the case study. The SD model developed was applied to the case study focusing on three management policies or scenarios, which are based on access rights to the forest resources within the study area. Specifically, the property arrangements examined in each scenario are: Policy 1 – status quo (i.e. continue present property rights arrangements); Policy 2 – local communities manage the forest exclusively; and Policy 3 – collaborative management involving both local communities and a private company. Results from the model show that the third policy is the most viable option, and also lead to a win–win solution.  相似文献   
75.
This study aims to identify services provided by forest ecosystems based on locals’ perceptions in the northern part of Jordan. By better understanding preferences of locals and by understanding why they value certain services more heavily, policy-makers and planning managers can make more effective decisions regarding development and conservation. Three hundred respondents were interviewed in order to collect information about forest ecosystem services (ES). Data collection was conducted using a structured questionnaire regarding ES provided by three forest types situated in northern Jordan. ES trade-offs and socio-ecological bundles were identified by analyzing respondents’ socioeconomic demographics and preferences of forest ES through multivariate canonical corresponding analysis (CCA). The statistical analysis indicated that the socioeconomic factors and forest type have an effect on social preferences toward ES. Results displayed a clear trade-off between provisioning services and regulating and cultural services. CCA demonstrated that 73% of the variation in ES value is explained by social factors (i.e. education level, income level, and gender), while 26% of perception variation was attributable to categories of ES supplied by each forest ecosystem. These findings imply that involving people in the place-specific management of public forests using the ES approach gives managers a clearer understanding of the benefits people recognize and value, as well as those they either are not aware of or do not value. Such information is useful in forest management and in public outreach. Although direct policy applications are limited by the research’s nature, the paper provides a starting point for incorporating forest users’ voices into policy discussions and management design.  相似文献   
76.
SUMMARY

Ecology has developed from its position as an obscure science to being at the interface of science and public policy. The impact of mankind can be described in ecological terms relating to population size, energy use and non-renewability. Sustainable development needs to be addressed on the basis of knowledge of ecological processes which maintain the environment in a state of change; the processes need to be conserved, not maintained in any particular state. Recent advances in the understanding of ecological processes are reviewed to highlight the potential contribution of this knowledge to the development of a sustainable policy. At the level of the population the significance of considering the extinction risks in the framework of spatio-temporal dynamics is now established indicating opportunities for planning land use more precisely to sustain biodiversity. Whilst the maintenance of habitats is generally the key to the persistence of biodiversity, they must be viewed as ever-changing mosaics within which cycles of succession, best described by Markovian sets of probabilities, are occurring continually. The extent to which these probabilities are distorted will determine whether the ecosystem returns to the same system or moves to a novel one. At the global level, biogeochemical cycles have a certain flexibility in relation to fluxes and stocks, hence pollution must be defined by relating the flow rate of the substance to this flexibility, which often permits the accommodation of anthropogenic perturbations. Non-sustainable processes can be defined in ecological terms, thus providing functional definitions of a sustainable policy and of sustainable development.  相似文献   
77.
This study aimed to assess soil nutrient status and heavy metal content and their impact on the predominant soil bacterial communities of mangroves of the Mahanadi Delta. Mangrove soil of the Mahanadi Delta is slightly acidic and the levels of soil nutrients such as carbon, nitrogen, phosphorous and potash vary with season and site. The seasonal average concentrations (μg/g) of various heavy metals were in the range: 14 810–63 370 (Fe), 2.8–32.6 (Cu), 13.4–55.7 (Ni), 1.8–7.9 (Cd), 16.6–54.7 (Pb), 24.4–132.5 (Zn) and 13.3–48.2 (Co). Among the different heavy metals analysed, Co, Cu and Cd were above their permissible limits, as prescribed by Indian Standards (Co=17 μg/g, Cu=30 μ g/g, Cd=3–6 μ g/g), indicating pollution in the mangrove soil. A viable plate count revealed the presence of different groups of bacteria in the mangrove soil, i.e. heterotrophs, free-living N2 fixers, nitrifyers, denitrifyers, phosphate solubilisers, cellulose degraders and sulfur oxidisers. Principal component analysis performed using multivariate statistical methods showed a positive relationship between soil nutrients and microbial load. Whereas metal content such as Cu, Co and Ni showed a negative impact on some of the studied soil bacteria.  相似文献   
78.
随着国家对生态环境的重视,林业建设不断深入,增加公益林补助金,延长退耕还林补助金期限,发展森林旅游,加快林权流转,发展林下经济等,使林地资源迅速升值,特别是城镇建设和国家重点项目建设,大额征地补偿款产生了巨大诱惑,又加之人们法律意识的加强,广大林农的维权意识不断提高,从而产生了各类林权纠纷,这就影响了社会的和谐稳定,阻碍了林业的发展.因此仔细分析我县林权纠纷产生的原因,掌握林权纠纷调处的程序,寻求探索解决林权纠纷的途径,对发展我县林业经济和保障社会稳定具有重要的意义.参8.  相似文献   
79.
Urban ecology is emerging as an integrative science that explores the interactions of people and biodiversity in cities. Interdisciplinary research requires the creation of new tools that allow the investigation of relations between people and biodiversity. It has been established that access to green spaces or nature benefits city dwellers, but the role of species diversity in providing psychological benefits remains poorly studied. We developed a user‐friendly 3‐dimensional computer program (Virtual Garden [ www.tinyurl.com/3DVirtualGarden ]) that allows people to design their own public or private green spaces with 95 biotic and abiotic features. Virtual Garden allows researchers to explore what elements of biodiversity people would like to have in their nearby green spaces while accounting for other functions that people value in urban green spaces. In 2011, 732 participants used our Virtual Garden program to design their ideal small public garden. On average gardens contained 5 different animals, 8 flowers, and 5 woody plant species. Although the mathematical distribution of flower and woody plant richness (i.e., number of species per garden) appeared to be similar to what would be expected by random selection of features, 30% of participants did not place any animal species in their gardens. Among those who placed animals in their gardens, 94% selected colorful species (e.g., ladybug [Coccinella septempunctata], Great Tit [Parus major], and goldfish), 53% selected herptiles or large mammals, and 67% selected non‐native species. Older participants with a higher level of education and participants with a greater concern for nature designed gardens with relatively higher species richness and more native species. If cities are to be planned for the mutual benefit of people and biodiversity and to provide people meaningful experiences with urban nature, it is important to investigate people's relations with biodiversity further. Virtual Garden offers a standardized tool with which to explore these relations in different environments, cultures, and countries. It can also be used by stakeholders (e.g., city planners) to consider people's opinions of local design. Programa de Computadora de Jardín Virtual para Uso en la Exploración de los Elementos de Biodiversidad que la Gente Desea en las Ciudades  相似文献   
80.
Land‐use dynamics and climatic gradients have large effects on many terrestrial systems. Exurban development, one of the fastest growing forms of land use in the United States, may affect wildlife through habitat fragmentation and building presence may alter habitat quality. We studied the effects of residential development and temperature gradients on bird species occurrence at 140 study sites in the southern Appalachian Mountains (North Carolina, U.S.A.) that varied with respect to building density and elevation. We used occupancy models to determine 36 bird species’ associations with building density, forest canopy cover, average daily mean temperature, and an interaction between building density and mean temperature. Responses varied with habitat requirement, breeding range, and migration distance. Building density and mean temperature were both included in the top occupancy models for 19 of 36 species and a building density by temperature interaction was included in models for 8 bird species. As exurban development expands in the southern Appalachians, interior forest species and Neotropical migrants are likely to decline, but shrubland or edge species are not likely to benefit. Overall, effects of building density were greater than those of forest canopy cover. Exurban development had a greater effect on birds at high elevations due to a greater abundance of sensitive forest‐interior species and Neotropical migrants. A warming climate may exacerbate these negative effects. Efectos del Desarrollo Exurbano y de la Temperatura sobre Especies de Aves en las Apalaches del Sur  相似文献   
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