نتایج جستجو برای: forests
تعداد نتایج: 39403 فیلتر نتایج به سال:
The goal of this study is to analyze the floristic patterns and the structure of disturbed and undisturbed upland forests, in Permanent Preservation Areas (PPAs) along the Moju river, in the Brazilian state of Pará. Trees with a diameter equal to or larger than 10cm at 1.30m from the ground (DBH) ≥10cm were analyzed for the upper stratum. For the middle stratum, individuals with DBH between 4.9...
finding a minimum allowable radius length of a circle horizontal curve is essential to reduce earthwork cost or damage to the forest ecosystem, as well as make driving more comfortable. the present study is conducted i) to analyze different radius lengths of circle horizontal curves using an integrated approach consists of a civil3d in concert with the field surveys, and ii) to propose a set of...
Mangrove forests are coastal ecosystems that found worldwide in tropical and subtropical zones. Oil spill causes damage to these marine ecosystems. The objective of this study is study the oil-degrading bacteria in some mangrove forests that located at Persian Gulf. In this study sediments and plant materials were collected from mangrove forests at Persian Gulf (Minab and Khamir ports). Oil-deg...
We study the maximum out forests of a (weighted) digraph and the matrix of maximum out forests. A maximum out forest of a digraph Γ is a spanning subgraph of Γ that consists of disjoint diverging trees and has the maximum possible number of arcs. If a digraph contains out arborescences, then maximum out forests coincide with them. We consider Markov chains related to a weighted digraph and prov...
1 This is one of three background papers commissioned by the United Nations Forum for Forests. Background paper 1: Focuses on economic contributions of forests, by Agrawal, Shepherd and Cashore; Background Paper 2: Forests and crosssectorial linkages, by Lele, Karsenty, Benson, Fétiveau, Agarwal and Goswami; and Background paper 3: The role of forests in a future world, by Agrawal et al. Deline...
The sustainable use of forests constitutes one of the great challenges for the future due to forests' large spatial coverage, long-term planning horizons and inclusion of many ecosystem services. The mission of the Future Forests programme is to provide a scientifically robust knowledge base for sustainable governance and management of forests preparing for a future characterized by globalizati...
the study examined prospects of selected forest fruits and vegetables in enugu north agricultural zone of enugu state, nigeria. structured interview schedule and focus group discussion were used to collect data from a sample of one hundred and twenty (120) respondents. data were analyzed using matrix rank ordering, percentage, mean scores and standard deviation. results of the study identified ...
گونه petasites albus (l.) gaertner به عنوان گزارش جدیدی از جنگلهای شمال ایران نام برده می شود. این گونه از petasites hybridus (l.) p. gaertner به علت داشتن کرک های دائمی تار عنکبوتی در زیر برگها و گل آذینی بلند و کشیده و گل های سفید رنگ با برگه های گریبانه ای غده دار متفاوت است.
increasing urbanisation and industrialisation have led to a dramatic reduction in forest area, and now only culturally protected remnants of natural forests and some new plantations remain in most areas of the north of iran. to investigate the status of the chemical and physical characteristics of soil under these remnant forests and assess the possible impacts of reforestation on soil properti...
Small and scattered patches of forests contrast sharply within the context flat monotonous dark green pastures in Dutch polder landscapes. These patches, with various types trees, are like little islands, surrounded by ditches. They not remnants original old peat swamp but farmers created past for particular purposes. Their names offer clear indications: addition to general name ‘small forests’...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید