نتایج جستجو برای: vegetation types forb

تعداد نتایج: 531616  

2005
Sebastian M. Riedel Howard E. Epstein Donald A. Walker David L. Richardson Monika P. Calef Amber Moody

Intraseasonal patterns of normalized difference vegetation index (NDVI), leaf area index (LAI), and phytomass were compared for four tundra vegetation types at Ivotuk, Alaska, during summer 1999. The vegetation types included moist acidic tundra (MAT), moist nonacidic tundra (MNT), mossy tussock tundra, and shrub tundra. The seasonal curves of NDVI were similar among the vegetation types but wi...

2017
Cui Li Bo Xiao Qinghai Wang Ruilun Zheng Juying Wu

To provide more insights into the responses of the soil seed bank and vegetation to human disturbance intensity, we selected four land use types, including: native grassland (no human disturbance), abandoned artificial grassland (light human disturbance), artificial grassland (moderate human disturbance), and farmland (severe human disturbance) in a semi-arid climate of northern China. The spec...

2009
Erwin Heine Monika Kriechbaum Franz Suppan

The paper describes and discusses the experience in mapping pasture types on the Tibetan Plateau. After pasture data recording in the fi eld campaign of 2004 the application of remote sensing and GIS to refi ne the vegetation mapping became viable. The vegetation types that resulted from the analysis of the fi eld data were aggregated into four main categories ( ́Kobresia pasture`, ́Miscellaneou...

Journal: :journal of rangeland science 2012
bahram gholinejad hassan pourbabaei asghar farajollahi eiraj parvane

today, in the rangeland management science and determination of rangecapacity, accurate and true information about range production is crucial. in fact, rangeproduction is considered as a basis for range management. the aim of this study was tocompare different methods for the estimation of forage production with four samplingmethods in the rangelands of kurdistan province, iran. the sampling m...

2006
Siegmar-W. Breckle

Afghanistan is a very mountainous country. It offers a big variety of ecological conditions, this means a big variety of vegetation types is covering land surface. These vegetation types are consisting of a high biodiversity, since the floristic influence from various neighbour regions is a considerable factor in floristic and vegetation pattern. On the other hand, Afghanistan is a very dry cou...

2007
PONDEROSA PINE JONATHAN D. BAKKER MARGARET M. MOORE

Long-term studies can broaden our ecological understanding and are particularly important when examining contingent effects that involve changes to dominance by long-lived species. Such a change occurred during the last century in Southwestern (USA) ponderosa pine (Pinus ponderosa) forests. We used five livestock grazing exclosures established in 1912 to quantify vegetation structure in 1941 an...

Abandonment of arable lands is the starting point of vegetation succession. The trajectory and speed of succession can be different according to the time of abandonment. The aim of this study is to assess the effect of abandonment periods on species richness, diversity and functional groups in shrublands and grasslands of Shirmard rangelands in Chaharmahal va Bakhtiri, Iran. A total of 96 abond...

Journal: :ecopersia 2015
davoud akhzari sahel haghighi

there are many reports of serious problems of dust storm events in the western parts of iran. based on many researches, iraq is one of the main sources of dust storms in western parts of iran. the radial basis function network (rbfn) model has been used to assess wind erosion hazard in iraq as a main source area of dust storms over several western cities of iran. the percentage of vegetation is...

Journal: :journal of rangeland science 2014
seyyed morteza abtahi amr ali shahmoradi ehsan zandi esfahan

abstract. the purpose of this study was to investigate vegetation dynamics and range conditions considering the climatic conditions and soil properties in haftooman, khoor and biabanak deserts, iran. for this purpose, after determining vegetation types and the associated species, the type of rangeland utilization, grazing season, the livestock type, the other relevant information, vegetation da...

Journal: :Open-file report / 2023

First posted June 21, 2023 For additional information, contact: Director, Forest and Rangeland Ecosystem Science Center777 NW 9th Street, Suite 400Corvallis, OR 97330 Increasing density of pinyon (Pinus spp.) juniper (Juniperus woodlands (hereinafter “pinyon-juniper”), as well expansion these into adjacent shrublands grasslands, has altered ecosystem function wildlife habitat across large areas...

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