نتایج جستجو برای: restricted grazing

تعداد نتایج: 132774  

2015
Wenqing Chen Ding Huang Nan Liu Yingjun Zhang Warwick B. Badgery Xiaoya Wang Yue Shen

Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the hig...

2015
Shuxia Zheng Wenhuai Li Zhichun Lan Haiyan Ren Kaibo Wang

Abundant evidence has shown that grazing alters plant functional traits, community structure and ecosystem functioning of grasslands. Few studies, however, have tested how plant responses to grazing are mediated by resource availability and plant functional group identity. We examined the effects of grazing on functional traits across a broad range of species along a soil moisture gradient in I...

Journal: :Ecology 2012
Tyler C Coverdale Andrew H Altieri Mark D Bertness

Belowground herbivory is commonly overlooked as a mechanism of top-down control in vegetated habitats, particularly in aquatic ecosystems. Recent research has revealed that increased densities of the herbivorous crab Sesarma reticulatum have led to runaway herbivory and widespread salt marsh die-off on Cape Cod, Massachusetts, USA. Aboveground herbivory is a major driver of this cordgrass habit...

2016
Junjie Wang Yan Zhao Ian Ray Mingzhou Song

Tolerance of alfalfa (Medicago sativa L.) to animal grazing varies widely within the species. However, the molecular mechanisms influencing the grazing tolerant phenotype remain uncharacterized. The objective of this study was to identify genes and pathways that control grazing response in alfalfa. We analyzed whole-plant de novo transcriptomes from grazing tolerant and intolerant populations o...

2012
Ivy B. J. Whitehorne Megan L. Harrison Nancy A. Mahony Patrick Robinson David J. Green

Livestock grazing is a dominant land use across North America and although the effects of grazing on birds have been studied in grassland, shrubland, and riparian habitats, studies of the effects in forests are rare. We investigated the effects of cattle grazing in forests on vegetation, the relationships between vegetation characteristics and the abundance of foraging and nesting guilds of bir...

2013
Lihua Zhou Yanling Zhu Guojing Yang Yiqi Luo

In northern China, the recent eco-environment protective policies played a very important role in the ecological environment protection and rehabilitation. To better understand the quantitative effect of the prohibiting grazing policy on grassland desertification reversal process, in this paper, Yanchi County was selected as a case study to conduct a quantitative research on the effect of prohi...

2014
Jae R. Pasari Daniel L. Hernández Erika S. Zavaleta

The interaction of resource availability and disturbance can strongly affect plant species richness and the spread of exotic plants. Several ecological theories posit that disturbance mediates the richness-reducing effects of increased competition as resource levels rise. In the low-nutrient serpentine grasslands of the San Francisco Bay Area, the fertilizing effects of atmospheric nitrogen (N)...

2013
Jixin Cao Xiaoping Wang Xiangyang Sun Lin Zhang Yun Tian

Grazing can cause changes in soil carbon (C) level. This study aimed to elucidate the response of soil labile organic carbon (SLOC) under four different grazing intensities: non grazing (NG), 0 sheep·ha(-1); light grazing (LG), 0.91 sheep·ha(-1); moderate grazing (MG), 1.82 sheep·ha(-1), and heavy grazing (HG), 2.73 sheep·ha(-1). Results showed that there was no significant difference in total ...

2017
Xiaotao Huang Geping Luo Huili He Xinxin Wang

Identifying the effects of grazing is critical for the conservation, protection and sustainable use of arid grassland ecosystems. However, research regarding the ecological effects of grazing along mountainous elevation gradients is limited in arid areas, particularly at the regional scale. Using the Biome-BGC grazing model, we explored the effects of grazing on grassland net primary productivi...

Journal: :Journal of dairy science 2016
J K Lowe C N Boyer A P Griffith J C Waller G E Bates P D Keyser J A Larson E Holcomb

Heifer rearing is one of the largest production expenses for dairy cattle operations, which is one reason milking operations outsource heifer rearing to custom developers. The cost of harvested feedstuffs is a major expense in heifer rearing. A possible way to lower feed costs is to graze dairy heifers, but little research exists on this topic in the mid-south United States. The objectives of t...

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