نتایج جستجو برای: far from agricultural lands therefore

تعداد نتایج: 5999716  

The presence of Damghan Erg in West of Damghan Playa indicates high wind activity in this desert region. Due to technological advances and population growth in recent decades, large parts of past land uses have changed. These changes can exacerbate wind erosion and affect lands sedimentation. In this study, first, the land use maps of years 1974 and 2003 were prepared. The comparison of these m...

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...

2014
H. K. Gibbs J. M. Salmon

Degraded lands have often been suggested as a solution to issues of land scarcity and as an ideal way to meet mounting global demands for agricultural goods, but their locations and conditions are not well known. Four approaches have been used to assess degraded lands at the global scale: expert opinion, satellite observation, biophysical models, and taking inventory of abandoned agricultural l...

2003
Wendel J. Hann Michael J. Wisdom Mary M. Rowland Thomas M. Quigley

Hann, Wendel J.; Wisdom, Michael J.; Rowland, Mary M. 2003. Disturbance departure and fragmentation of natural systems in the interior Columbia basin. Res. Pap. PNW-RP-545. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 19 p. We integrated landscape data from science assessments of the interior Columbia basin (basin) into one variable that func...

2014
Tola Gemechu Ango Kristoffer Hylander

Farmers’ practices in the management of agricultural landscapes influence biodiversity with implications for livelihoods, ecosystem service provision, and biodiversity conservation. In this study, we examined how smallholding farmers in an agricultureforest mosaic landscape in southwestern Ethiopia manage trees and forests with regard to a few selected ecosystem services and disservices that th...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2009
Jeanine M Rhemtulla David J Mladenoff Murray K Clayton

One-third of net CO(2) emissions to the atmosphere since 1850 are the result of land-use change, primarily from the clearing of forests for timber and agriculture, but quantifying these changes is complicated by the lack of historical data on both former ecosystem conditions and the extent and spatial configuration of subsequent land use. Using fine-resolution historical survey records, we reco...

Abolghasem Dadrasi Sabzevar Ali Ariapour, Sara Toloee

Land use may be regarded as one of the most important factors affecting theenvironment with respect to human activities. So far, destroying the rangelands andchanging them into the waste lands and poor rangelands has been proposed as the mostsignificant variations of land use done by human beings. This paper has been conducted toevaluate the variations of vegetation percentage and land uses in ...

Journal: :iranian journal of toxicology 0
mohammad rezaeian department of animal and poultry health and nutrition, university of tehran, tehran, iran. mahmoud tohidi moghadam department of animal and poultry health and nutrition, university of tehran, tehran, iran.

background: heavy metals (hms) are one of the most important polluting substances emitted to the environment during cement production. tehran cement factory located in the southeastern of tehran, iran, closer to agricultural lands cultivates alfalfa, barley, and maize as feed. the objective of the study was to determine the concentration of hms in agricultural soils. methods: thirty six soil sa...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - دانشکده علوم انسانی 1389

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

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