نتایج جستجو برای: protection of forests
تعداد نتایج: 21185772 فیلتر نتایج به سال:
The protection of tropical forests is one of the most urgent issues in conservation biology because of the rapid deforestation that has occurred over the last 50 years. Even in protected forests, the anthropogenic effects from newly expanding villages such as harvesting of medicinal plants, pasturing cattle and forest fires can induce environmental modifications, especially on the forest floor....
In the current scenario of a fragmented Atlantic Forest, with less than 7% of the original cover remaining, the dominant agricultural and agroforestal matrices should be incorporated into conservation planning. However, little information is available on the conservation value of different land uses, especially those of commercial tree plantations. We studied bird communities in native forests ...
Topographic Variation in Aboveground Biomass in a Subtropical Evergreen Broad-Leaved Forest in China
The subtropical forest biome occupies about 25% of China, with species diversity only next to tropical forests. Despite the recognized importance of subtropical forest in regional carbon storage and cycling, uncertainties remain regarding the carbon storage of subtropical forests, and few studies have quantified within-site variation of biomass, making it difficult to evaluate the role of these...
canopy density is linked to weaker or no thermophilisation. By offering more shadow, it appears, the trees are shielding the ground vegetation from the temperature rise. “We believe that the effect of the tree canopy is to moderate changes in temperature at the lower levels in the wood — particularly where, as is the case in much of Europe, woods have been becoming denser and shadier in recent ...
Natural resource managers are often expected to achieve both environmental protection and economic development even when there are fundamental trade-offs between these goals. Adaptive management provides a theoretical structure for program administrators to balance social priorities in the presence of trade-offs and to improve conservation targeting. We used the case of Mexico's federal Payment...
Current forest Free Air CO(2) Enrichment (FACE) experiments are reaching completion. Therefore, it is time to define the scientific goals and priorities of future experimental facilities. In this opinion article, we discuss the following three overarching issues (i) What are the most urgent scientific questions and how can they be addressed? (ii) What forest ecosystems should be investigated? (...
— Few examples exist in the common property literature of community-managed forestry enterprises (CFEs) operating in competitive markets. Yet, in Mexico, there are hundreds of such examples at varying levels of vertical integration. At a time when devolution of rights to forests is expanding worldwide, collective management of timber operations presents an emerging community forestry policy opt...
عنوان: بررسی اوضاع فرهنگی گیلان (از انقلاب مشروطیت تا به قدرت رسیدن رضا شاه ) نویسنده: افضل افشاری سال :90-1389 استاد راهنما: دکتر ابوطالب سلطانیان استاد راهنما: دکتر حسن کهنسال واجارگاه چکیده: این پژوهش می کوشد اوضاع فرهنگی گیلان را از دور? مشروطیت تا ظهور رضا خان بررسی نماید و کم و کیف آن را آشکار سازد. انقلاب مشروطیت دو دستاورد مهم فرهنگی را در پی داشت؛ یکی انتشار گسترد? مطبوعات د...
Land degradation has expanded in the Mediterranean region as a result of a variety of factors, including economic and population growth, land-use changes and climate variations. The level of land vulnerability to degradation and its growth over time are distributed heterogeneously over space, concentrating on landscapes exposed to high human pressure. The present study investigates the level of...
Recent decades have seen a rapid movement towards decentralising forest rights and tenure to local communities and indigenous groups in both developing and developed nations. Attribution of local and community rights to forests appears to be gathering increasing momentum in many tropical developing countries. Greater local control of forest resources is a response to the failure of government a...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید