نتایج جستجو برای: karst

تعداد نتایج: 4636  

Journal: :Ambio 2006
Baiping Zhang Fei Xiao Hongzhi Wu Shenguo Mo Shouqian Zhu Lifei Yu Kangning Xiong Anjun Lan

Karst landscapes—regions characterized by sinkholes, caves, springs, underground rivers, and slowly dissolving bedrock— constitute about 25% of the world’s land surface (1). Although some karst landscapes are attractive and of aesthetic value, most of them are recognized as fragile zones unsuitable as human habitats— mainly due to extremely poor soil cover, or a complete lack of soil, and rapid...

2014
Jie Zhao Shengping Li Xunyang He Lu Liu Kelin Wang

Karst ecosystems are fragile and are in many regions degraded by anthropogenic activities. Current management of degraded karst areas focuses on aboveground vegetation succession or recovery and aims at establishing a forest ecosystem. Whether progressive succession of vegetation in karst areas is accompanied by establishment of soil biota is poorly understood. In the present study, soil microb...

2017
Mateja Lumpert Samo Kreft

BACKGROUND Information on the use of medicinal plants in Karst and Gorjanci is not available in the literature, but collection of plants is still an important and widespread practice in these regions. Karst and Gorjanci are two remote regions in Slovenia that are only 120 km apart but have different climates; one region is close to the Italian border, and the other is near the Croatian border. ...

2009
Yuemin Yue Kelin Wang Bo Liu Bing Zhang Ru Li Quanjun Jiao Yizun Yu

As band widths are narrow and range of spectra is wide, subtle differences in spectral features can be extracted and used for mapping physical and chemical properties of bare substrate with imaging spectroscopy. However, the use of spectral characteristics of substrates is not accessible if substrate was covered by vegetation. In this study, we explored the feasibility of extracting karst ecoen...

2005
Rick Olson Caroline Noble

Karst landscape overview THE 52,830 ACRES OF MAMMOTH CAVE NATIONAL PARK are part of the South-Central Kentucky Karst, which is characterized by subterranean drainage to springs on major rivers. From the southeast to the northwest portion of the landscape (Figure 1), there is a gradient of decreasing maturity in karst development, which corresponds to the regional dip of the bedrock. The major c...

2016
Yuan Yun Hongmei Wang Baiying Man Xing Xiang Jianping Zhou Xuan Qiu Yong Duan Annette S. Engel

Enhanced monsoon duration and soil acidification from acid rain are expected to impact the distribution of microbial communities in surface and subsurface environments, although these impacts are poorly understood for most systems. In central China, soluble carbonate bedrock forms extensive karst landscapes. Current predictions are that the amount of monsoonal precipitation and acid rainfall in...

Journal: :American journal of primatology 2007
Andrew J Marshall Leonardo A Salas Suzette Stephens Linda Engström Erik Meijaard Scott A Stanley

The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and East Kutai regencies in the northern half of the province. The Sangkul...

2013
Yuguo Liu Changcheng Liu Shijie Wang Ke Guo Jun Yang Xinshi Zhang Guoqing Li

Karst ecosystems are important landscape types that cover about 12% of the world's land area. The role of karst ecosystems in the global carbon cycle remains unclear, due to the lack of an appropriate method for determining the thickness of the solum, a representative sampling of the soil and data of organic carbon stocks at the ecosystem level. The karst region in southwestern China is the lar...

Journal: :مدیریت مخاطرات محیطی 0
شکور سلطانی دکتری ژئومورفولوژی، وزارت نیرو ایثار نورایی صفت دانشجوی کارشناسی ارشد آموزش محیط زیست، دانشگاه تهران طاهر ولی پور دانشجوی کارشناسی ارشد هیدروژئومورفولوژی، دانشگاه شهید بهشتی عبدالکریم ویسی دانشجوی دکتری ژئومورفولوژی، دانشگاه تهران احمد عباسیان کارشناس ارشد ژئومورفولوژی، دانشگاه تهران

vulnerability and contamination risk assessment is of great importance in karst aquifer management. because of vastness of karst in zagros, natural conditions and human activity within the region of aquifer, pollution emission has become one of the most important challenges in front of zagros aquifers. the purpose of this study is to assess marab aquifer vulnerability, using riske model and, de...

ژورنال: علوم آب و خاک 2018

To determine the potential for groundwater contamination, vulnerability should be evaluated in different areas susceptible to contamination should be investigated. Aquifer (carbonate) karst or part of it is karst aquifer in the western region of Iran; due to the natural conditions of the region and human activities, they are susceptible to contamination by carbonate aquifer through holes devour...

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