نتایج جستجو برای: forest species changing

تعداد نتایج: 771031  

2014
Zuzana Sarvašová Zuzana Dobšinská Miroslav Kovalčík

Background and Purpose: Innovations play an important role in multifunctional forestry due to changing demands for forest goods and services. The multifunctionality can be a result of a joint provision of several outputs from individual forest holding or specialized forest activities. The goal of this paper is to make a comparative analysis from data obtained in two surveys in 2002 and 2010 rel...

Journal: :global journal of environmental science and management 0
l.g. aribal department of forest biological sciences, college of forestry and environmental science, central mindanao university, musuan, bukidnon, philippines j.g. bonggay department of forest biological sciences, college of forestry and environmental science, central mindanao university, musuan, bukidnon, philippines e.s. fernando department of forest biological sciences, college of forestry and natural resources, university of the philippines, los baños, laguna, philippines

leaf size indices of the tree species in the peatland of agusan del sur in mindanao in philippines was examined to deduce the variation of forest structure and observed forest zonation.  using raunkiaer and webb’s leaf size classification, the leaf morphometrics of seven tree species consistently found on the established sampling plots were determined.  the species includes ternstroemia philipp...

2011

Deforestation and habitat fragmentation that arise largely due to the conversion of forests to other agricultural land-use types and over-utilization of forest resources to satisfy the food and energy requirements of the increasing population are major environmental concerns in northern Ethiopia. Understanding plant species diversity and spatial distribution along environmental gradients is cru...

2011

Deforestation and habitat fragmentation that arise largely due to the conversion of forests to other agricultural land-use types and over-utilization of forest resources to satisfy the food and energy requirements of the increasing population are major environmental concerns in northern Ethiopia. Understanding plant species diversity and spatial distribution along environmental gradients is cru...

2016
Gilbert Barrantes Diego Ocampo José D. Ramírez-Fernández Eric J. Fuchs

Deforestation and changes in land use have reduced the tropical dry forest to isolated forest patches in northwestern Costa Rica. We examined the effect of patch area and length of the dry season on nestedness of the entire avian community, forest fragment assemblages, and species occupancy across fragments for the entire native avifauna, and for a subset of forest dependent species. Species ri...

Journal: :محیط شناسی 0
علی جعفری استادیار گروه علوم جنگل دانشکدۀ منابع طبیعی دانشگاه شهرکرد زهرا آرمان دانشجوی کارشناسی ارشد جنگل داری، دانشکدۀ منابع طبیعی و علوم زمین، دانشگاه شهرکرد علی سلطانی استادیار گروه علوم جنگل، دانشکدۀ منابع طبیعی و علوم زمین، دانشگاه شهرکرد علی لطفی هیات علمی دانشگاه صنعتی اصفهان

introduction forest ecosystems have continuously downgraded due to every environmental pressure including climate change, aerosols deposits, industrial pollutions and other degradation factors. the output soon or late would be a different forest. forest monitoring is a well-regulated and usually long running procedure, which has the ability to detect these phenomena and reactions based on aims ...

Dorna Rezaei Maziar Haidari

Silvicultural operation need to notice the species diversity. To this study Gomarlang district in marivan region, northern zagros forest was selected. In this study 30 circle sample plots (500 m2) were collected by random method. In every sample plot the kind of species and number of trees and shrub were recorded. In the sample plots the micro plots of 5 m by 5 m (i.e. area of 25 m2) were desig...

سالاروند, مرضیه, عرفانزاده, رضا, کوچ, یحیی,

This study aimed to compare plant species diversity indices (diversity and richness) and some physico-chemical properties of soil among forest, ecotone and rangeland habitats. Vegetation sampling was done randomly at each habitat. One dominant community was selected in each habitat and one key area was distinguished in each community and 8×1m2 plots were randomly established in each key area. I...

توانکار, فرزام, نیکوی, مهرداد,

Rotten and dead trees are the main component of forest ecosystems and play an important role in maintaining forest biodiversity. In this research frequency and characteristics of large diameter trees (normal, rotten, and dead trees) with diameter at breast height greater than 60 cm were studied in two compartments (selective logged and protected) in Asalem-Nav forest. Random systematic sampling...

2011
Kathryn N. Riley Robert A. Browne

We examined diversity, community composition, and wing-state of Carabidae as a function of forest age in Piedmont North Carolina. Carabidae were collected monthly from 396 pitfall traps (12×33 sites) from March 2009 through February 2010, representing 5 forest age classes approximately 0, 10, 50, 85, and 150 years old. A total of 2,568 individuals, representing 30 genera and 63 species, were co...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید

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