نتایج جستجو برای: grassland

تعداد نتایج: 10371  

2003
D. L. PETERSON

This study assesses the ability of multitemporal Landsat Thematic Mapper (TM) data and the normalized diVerence vegetation index (NDVI) to spectrally separate grazed cool season and warm season grassland cover types in Douglas County, Kansas. Biophysical data collected during the summer of 1997 suggest that diVerences in the per cent of total living vegetation cover, per cent of senescent veget...

Journal: :IJTM 2002
Tie Wang Robin Pollard

Resulting from centuries of traditional animal husbandry, extensive grasslands belong to the most important natural tourism resources in Central Europe adding to the amenity values of many landscapes. Facing agricultural market pressures, they are endangered by agricultural intensification as well as by abandonment. Both developments threaten grassland values for tourists and recreationists. Ho...

2011
Samiran Banerjee Yuhong He Xulin Guo Bing Cheng Si

A considerable portion of Canada’s landmass is covered by grassland ecosystems. Insight into the grassland spatial heterogeneity will not only contribute to better understanding of the scale dependent ecological processes but will also help in management and monitoring. Leaf area index (LAI) is a key structural attribute of grassland that reflects primary production. It is well-known that topog...

Journal: :Remote Sensing 2017
Jens L. Hollberg Jürgen Schellberg

Monitoring the reaction of grassland canopies on fertilizer application is of major importance to enable a well-adjusted management supporting a sustainable production of the grass crop. Up to date, grassland managers estimate the nutrient status and growth dynamics of grasslands by costly and time-consuming field surveys, which only provide low temporal and spatial data density. Grassland mapp...

Journal: Journal of Herbal Drugs 2016
Forough Mortazaeinezhad Mahtab Esfahanizadeh Hoseinpoor,

Background & Aim: Persian shallot (Allium hirtifolium Boiss) with common name of "Musir" is one of the endemic medicinal plants in Iran. Leaves and bulbs with antibacterial, antifungal, anticancer, anti-diabetes and anti-obesity effects are edible parts of this plant. The tissue culture is an influential method to multiply plant productions in order to meet demands of ...

2013
Kevin S. Ellison Christine A. Ribic David W. Sample Megan J. Fawcett John D. Dadisman

Globally, grasslands and the wildlife that inhabit them are widely imperiled. Encroachment by shrubs and trees has widely impacted grasslands in the past 150 years. In North America, most grassland birds avoid nesting near woody vegetation. Because woody vegetation fragments grasslands and potential nest predator diversity and abundance is often greater along wooded edge and grassland transitio...

2009
Christine Rösch J. Skarka K. Raab V. Stelzer

In many regions of Europe, grassland shapes the landscape and fulfils important functions in protecting nature, soil, and water. However, the traditional uses of grassland for forage production are vanishing with progress in breeding and structural adaptations in agriculture. On the other hand, the demand for biomass energy is rising due to political sustainability goals and financial measures ...

2006
Martin Potthoff Kerri L. Steenwerth Louise E. Jackson Rebecca E. Drenovsky Kate M. Scow Rainer G. Joergensen

Agricultural practices have strong impacts on soil microbes including both the indices related to biomass and activity as well as those related to community composition. In a grassland restoration project in California, where native perennial bunchgrasses were introduced into non-native annual grassland after a period of intensive tillage, weeding, and herbicide use to reduce the annual seed ba...

2016
Xuefeng Zhang Jianming Niu Alexander Buyantuev Qing Zhang Jianjun Dong Jing Zhang

Ecosystem services (ESs) and their transformations in northern China play a crucial role in regional sustainability. During the past several decades, grassland degradation has become one of the most important ecological and economic issues in this region. Therefore, understanding the impacts of grassland degradation and restoration on ESs is essential for maintaining ecological resilience and s...

2016
Abel Jose Robles Stephen J. Dinsmore William R. Clark

The Iowa landscape has been drastically transformed due to agricultural practices, causing population declines in many grassland bird species. Of greatest concern are bird species that are considered to be area sensitive. The Iowa State Preserve System is composed of tracts of prairies, wetlands, and woodlands that can provide habitat for many grassland bird species. This study provides an inve...

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