نتایج جستجو برای: steppe rangeland

تعداد نتایج: 6942  

Journal: :Remote Sensing 2018
Shilong Ren Shuhua Yi Matthias Peichl Xiaoyun Wang

Vegetation phenology in temperate grasslands is highly sensitive to climate change. However, it is still unclear how the timing of vegetation phenology events (especially for autumn phenology) is altered in response to climate change across different grassland types. In this study, we investigated variations of the growing season start (SOS) and end (EOS), derived from Moderate Resolution Imagi...

Journal: :مرتع و آبخیزداری 0
پژمان طهماسبی استادیار گروه مرتع و آبخیزداری دانشکدة منابع طبیعی و علوم زمین دانشگاه شهرکرد

fire is one of the most important ecological factors in semi-steppe rangelands directing plant community composition, diversity, structure and function of ecosystems. our primary aim was to examine the effect of fire on plant community composition, diversity, plant species restoration and animal selectivity in semi-steppe rangeland in karsanak region, chaharmahal & bakhtiari province in years 2...

2008
Yan Zhao Zicheng Yu Fahu Chen

Pollen data from 30 sites in arid and semi-arid regions of China were reviewed to document regional patterns of Holocene vegetation and climate change and to understand the large-scale controls on these changes. Vegetation at most sites in eastern Inner Mongolia switched between forest, forest steppe, and typical steppe, showing maximum moisture conditions before 6 ka (1 ka 1⁄4 1000 cal yr BP) ...

Journal: :journal of rangeland science 2010
m.t. gaemi m. akbarzade sh. abedi

the study of the exclosure effects on the vegetation changes undergrazing and non-grazing conditions in the rangeland areas has particularimportance in the rangeland improvement and revivification projects. theresearch was accomplished in semi-steppe khoybilehvar area, from 1999 to2005. vegetation cover was annually measured within fixed plots during transact.the results showed that during nine...

2005
Ian A. Simpson Amanda M. Thomson Jennifer L. Brown

The introduction of domestic livestock particularly sheep and rangeland grazing by Norse settlers to Faroe during the 9th century has generally been described as a major pressure on a sensitive landscape, leading to rapid and widespread vegetation change and contributing to land degradation. This view has, however, been developed without consideration of Norse grazing management practices which...

2010
Jonathan B. Thayn Kevin P. Price Randall B. Boone

We examine relationships between landscape scale measurements of rangeland complexity and cattle stocking rates in Kansas. Rangeland complexity was characterized using Advanced Very High Resolution Radiometer (AVHRR) satellite imagery and the USGS National Land Cover Dataset (NLCD). Satellite Normalized Difference Vegetation Index (NDVI) values were summed over the 2002 growing-season and then ...

2017
Ru An Hui-Lin Wang Xue-Zhi Feng Zhe Wang Ying Wang Ying-Hui Zhao

the “Three-River Headwaters” region (TRHR) rangeland ecosystem is extremely sensitive and fragile, and in recent years has undergone continuous degradation. The vast area and severe nature conditions inhibit data acquisition and field experiments, resulting in different understandings about the spatial characteristics and dynamics of rangeland degradation in the region. Therefore, reliable moni...

2004
C. Tong J. Wu S. Yong J. Yang W. Yong

Steppe degradation is a major ecological and economic problem in the Inner Mongolia steppe region, China because it reduces grassland productivity and leads to desertification. The objective of this study was to assess the spatial extent and severity of steppe degradation in the Xilin River Basin, Inner Mongolia using a landscape-scale approach. Our approach combined information from field surv...

  Differences between plant biodiversity and grazing pastures grazed under improved management of rangeland habitat is of particular importance. The purpose of this study was to compare semi-steppe rangeland vegetation of Prdanan in the city of Piranshahr in the field under grazed and enclosed sites were considered. Sampled in both grazed and systematic random pastured five 40 meters trans...

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