نتایج جستجو برای: cultivated land size

تعداد نتایج: 687875  

2008
Jun Tan Hongyou Su

Since 1949, the information of land tenure has a positive effect on defining the scope of collective land and state-owned land, implementing the system of cultivated land protection and land use control, designing general land use planning, etc. But as the economic and social development, the existing land tenure information is not appropriate anymore and results in many problems. The emphasis ...

Journal: :Journal of environmental management 2010
Alberto L Teixido Luis G Quintanilla Francisco Carreño David Gutiérrez

Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (n...

2015
Prajal Pradhan Günther Fischer Harrij van Velthuizen Dominik E. Reusser Juergen P. Kropp Jose Luis Gonzalez-Andujar

Global food production needs to be increased by 60-110% between 2005 and 2050 to meet growing food and feed demand. Intensification and/or expansion of agriculture are the two main options available to meet the growing crop demands. Land conversion to expand cultivated land increases GHG emissions and impacts biodiversity and ecosystem services. Closing yield gaps to attain potential yields may...

2014
Yunbin Qin Zhongbao Xin Xinxiao Yu Yuling Xiao

Understanding effects of land-use changes driven by the implementation of the "Grain for Green" project and the corresponding changes in soil organic carbon (SOC) storage is important in evaluating the environmental benefits of this ecological restoration project. The goals of this study were to quantify the current soil organic carbon density (SOCD) in different land-use types [cultivated land...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2009
Thomas K Rudel Laura Schneider Maria Uriarte B L Turner Ruth DeFries Deborah Lawrence Jacqueline Geoghegan Susanna Hecht Amy Ickowitz Eric F Lambin Trevor Birkenholtz Sandra Baptista Ricardo Grau

Does the intensification of agriculture reduce cultivated areas and, in so doing, spare some lands by concentrating production on other lands? Such sparing is important for many reasons, among them the enhanced abilities of released lands to sequester carbon and provide other environmental services. Difficulties measuring the extent of spared land make it impossible to investigate fully the hyp...

2012
David M. Johnson

A ca. 2010, 30 m resolution map depicting annually tilled areas across the conterminous United States was developed. Input sources included four years, spanning 2008–2011, of annual national-level coverage Cropland Data Layer (CDL) land cover classifications as produced by the National Agricultural Statistics Service. Derived total land area under tillage from the aggregate CDL product equaled ...

2016
Natali Hernández-Becerra Yunuen Tapia-Torres Ofelia Beltrán-Paz Jazmín Blaz Valeria Souza Felipe García-Oliva

BACKGROUND Global demand for food has led to increased land-use change, particularly in dry land ecosystems, which has caused several environmental problems due to the soil degradation. In the Cuatro Cienegas Basin (CCB), alfalfa production irrigated by flooding impacts strongly on the soil. METHODS In order to analyze the effect of such agricultural land-use change on soil nutrient dynamics ...

Journal: :مرتع و آبخیزداری 0
لیلا زندی دانشجوی کارشناسی ارشد مرتعداری، دانشکده منابع طبیعی و علوم دریایی، دانشگاه تربیت مدرس رضا عرفانزاده دانشیار دانشکده منابع طبیعی و علوم دریایی، دانشگاه تربیت مدرس حامد جنیدی جعفری استادیار گروه مرتعداری دانشکده منابع طبیعی، دانشگاه کردستان، ایران

this study aimed to determine the effect of land use changes from rangeland to horti-agricultural lands on the most important qualitative characteristics of soil such as total soil carbon and particulate organic matter, in salavatabad region, sanandaj. in the present study, one rangeland, two cultivated pea lands, two cultivated wheat lands and two gardens were selected in growth season in the ...

2011
R. R. Ratnayake G. Seneviratne

* Corresponding author ([email protected]) Abstract: Soil carbohydrates (SC) are important parameters in determining soil fertility in different land uses, particularly in the tropics. There are no tropical studies reported so far on the effect of heterogeneneous land uses on the concentration of SC. Therefore, SC under 13 different land uses including forests and adjacent cultivated lands in S...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2008
Jingzhu Zhao Qishan Luo Hongbing Deng Yan Yan

This paper introduces the concepts and aims of sustainable agriculture in China. Sustainable agricultural development comprises sustainability of agricultural production, sustainability of the rural economy, ecological and environmental sustainability within agricultural systems and sustainability of rural society. China's prime aim is to ensure current and future food security. Based on projec...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید