نتایج جستجو برای: grasslands

تعداد نتایج: 6042  

2015
X. Lu Y. Yan J. Sun X. Zhang Y. Chen X. Wang G. Cheng

Since the 1980s, alpine grasslands have been seriously degraded on the Tibetan Plateau. Grazing exclusion by fencing has been widely adopted to restore degraded grasslands. To clarify the effect of grazing exclusion on soil quality, we investigated soil properties and nutrients by comparing free-grazing (FG) and grazing exclusion (GE) grasslands in Tibet. Soil properties – including soil bulk d...

Journal: :Proceedings. Biological sciences 2016
Maria S Vorontsova Guillaume Besnard Félix Forest Panagiota Malakasi Justin Moat W Derek Clayton Paweł Ficinski George M Savva Olinirina P Nanjarisoa Jacqueline Razanatsoa Fetra O Randriatsara John M Kimeu W R Quentin Luke Canisius Kayombo H Peter Linder

Grasses, by their high productivity even under very low pCO2, their ability to survive repeated burning and to tolerate long dry seasons, have transformed the terrestrial biomes in the Neogene and Quaternary. The expansion of grasslands at the cost of biodiverse forest biomes in Madagascar is often postulated as a consequence of the Holocene settlement of the island by humans. However, we show ...

2007

activity vary along a gradient from complete destruction in the worst case to preserved fragments of presumed pristine stands in the best. Yet the most “pristine” California grasslands represent only a small proportion of California’s current grasslands, and even they include some non-native species (Safford and Harrison 2001; Stromberg et al. 2001; Gelbard and Harrison 2003). Some grasslands m...

2017
Irene Martín-Forés Greg R Guerin Andrew J Lowe

Weeds are commonly considered a threat to biodiversity, yet interactions between native and exotic species in grasslands are poorly understood and reported results vary depending on the spatial scale of study, the factors controlled for and the response variables analysed. We tested whether weed presence and abundance is related to declines in biodiversity in Australian grasslands. We employed ...

2006
ALVES DE OLIVEIRA

Faunal inventories of the highest peaks of the Atlantic forests of South America, in the Caparaó and Itatiaia mountain ranges in Southeastern Brazil, have revealed a new community of small mammals. The species making up this community appear to be restricted to the highest altitudinal zones and are found in close association with scattered montane grasslands (campos de altitude). Their phylogen...

2007
S. M. Thomas M. W. Palmer

The montane (shola) grasslands of Western Ghats, South India are a component of a landscape mosaic including the better-studied shola forests. The conservation of the grasslands depends upon understanding their ecology. This review compiles available information and aims to evaluate the conservation potential of these grasslands. Most studies on these grasslands are descriptive in nature. There...

Journal: :Annals of botany 2012
F P O'Mara

BACKGROUND Grasslands are a major part of the global ecosystem, covering 37 % of the earth's terrestrial area. For a variety of reasons, mostly related to overgrazing and the resulting problems of soil erosion and weed encroachment, many of the world's natural grasslands are in poor condition and showing signs of degradation. This review examines their contribution to global food supply and to ...

2017
Longhua Xu Buqing Yao Wenying Wang Fangping Wang Huakun Zhou Jianjun Shi Xinquan Zhao

Artificial grasslands play a role in carbon storage on the Qinghai-Tibetan Plateau. The artificial grasslands exhibit decreased proportions of graminate and increased species richness with age. However, the effect of the graminate proportions and species richness on ecosystem C stocks in artificial grasslands have not been elucidated. We conducted an in situ13C pulse-labeling experiment in Augu...

2016
Maite Gartzia Federico Fillat Fernando Pérez-Cabello Concepción L Alados

Over the last decades, global changes have altered the structure and properties of natural and semi-natural mountain grasslands. Those changes have contributed to grassland loss mainly through colonization by woody species at low elevations, and increases in biomass and greenness at high elevations. Nevertheless, the interactions between agropastoral components; i.e., ecological (grassland, env...

Journal: :New Zealand Journal of Agricultural Research 1974

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