نتایج جستجو برای: eg percentage of canopy cover

تعداد نتایج: 21181098  

بصیری, مهدی , خواجه الدین, سیدحمال الدین , وهابی, محمد رضا ,

Short-term changes (5 years) in canopy cover, species composition and forage production were studied under protection from grazing and grazed condition in 19 range sites in Fereydan region, Isfahan province. In this study, density, canopy cover and forage production data were obtained from quadrates inside and outside exclosures in the spring of 1983. These parameters were studied again in 1988...

2002
Janet Franklin Frank W. Davis Paul Lefebvre

T h e effect of variable tree canopy cover, shadows, and topography on Thematic Mapper (TM) data was examined for blue oak (Quercus douglasii) woodland and wooded grassland on rugged terrain in central California. Thematic Mapper data were analyzed from September 1986 (trees in leaf, grass understory senescent) and December 1984 (trees leafless, grasses emerging. Tree cover measured in 84 60 m ...

2012
JENNIFER E. HESS

Wyoming big sagebrush (Artemisia tridentata wyomingensis) treatments are often implemented to improve breeding habitat for greater sage-grouse (Centrocercus urophasianus), a species of considerable conservation concern. In 2008 and 2009, we measured vegetation structure available to sage-grouse for breeding at 19 sites that were prescribed burned during 1990–1999 and 2000–2006, 6 sites that wer...

Journal: :اکو هیدرولوژی 0
سعید یوسفی کارشناس ارشد بیابان زدایی، دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان، اصفهان سید حمید متین خواه استادیار، دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان، اصفهان فرزاد روحانی مربی، دانشکدة منابع طبیعی، دانشگاه صنعتی اصفهان، اصفهان محسن نائل استادیار، دانشکدة کشاورزی، دانشگاه همدان

stemflow is a part of precipitation which enters in to the soil through stem and branches. in this paper, we studied the stem flow features of anabasis aphylla as a bush and pteropyrum aucheri as a shrub in northwest of isfahan. stemflow production mechanism as well as the effects of canopy cover on this system was investigated during precipitation seasons in 2013 and 2014. a rain simulator was...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه لرستان - دانشکده ادبیات 1394

abstract the purpose of this study was to find out the effect of applying the principles of group-dynamic assessment (g-da) on learning of conditional structures in english by iranian efl learners at the intermediate level, which according to the formal educational system in iran, includes students who are in their second year of studying in high schools of koohdasht city. this study was a qua...

ژورنال: علوم زراعی ایران 2020
Bagheri, Alireza, Mondani, Farzad, Nosratti, Iraj, Zargarian, Negin,

Weeds are one of the most important factors in reducing yield in legumes crops. Therefore, awareness of the interaction between weeds and crops as well as identification of their spatial variation pattern in the field is important. To investigate the the effect of  weeds on seed yield of lentil, and also to study the spatial distribution pattern of weeds under rainfed conditions, a field experi...

Excessive use of water and soil resources, especially in arid and semi-arid regions, increases soil erosion, destructive storms, the occurrence of dust, and desertification. Therefore, to prevent environmental problems in these areas, it is necessary to efficiently manage water and soil resources in arid and semi-arid regions. Rainwater catchment systems are one of the management and operationa...

Journal: :journal of rangeland science 2012
hossein azarnivand esmaeil alizadeh anvar sour ali hajibeglo

the effects of range management plans (rmp) on soil and vegetationcharacteristics were studied in eshtehard rangelands at alborz province. the parameters ofyield, canopy cover, range condition and trend, bulk density, organic matter (om%),nitrogen (n), phosphorous (p) and potassium (k) were estimated on soil samples in sitesof ghenzel cheshmeh as rmp and sanctum of rahmanyeh village. the data w...

2017
Scott R. Abella

–Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa pine-Gambel oak (Quercus gambelii) forests to ...

2012
John W. Coulston Gretchen G. Moisen Barry T. Wilson Mark V. Finco Warren B. Cohen

0099-1112/12/7807–715/$3.00/0 © 2012 American Society for Photogrammetry and Remote Sensing Abstract Tree canopy cover is a fundamental component of the landscape, and the amount of cover influences fire behavior, air pollution mitigation, and carbon storage. As such, efforts to empirically model percent tree canopy cover across the United States are a critical area of research. The 2001 nation...

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