نتایج جستجو برای: soil erosion and decreasing of soil fertility

تعداد نتایج: 24078045  

2017
Carlos Chávez Carlos Fuentes Fernando Brambila

Currently gravity irrigation remains the most widely used in agricultural areas and 90 percent of plantings, the water is applied to the plots by gravity. One of the main problems with these systems is erosion, which is a by product of the erosive forces of water over the row, which brings soil loss and therefore decreases in crop yield. Erosion is the removal of surface soil material caused by...

ژورنال: آبخیزداری ایران 2020
Sahandi, Khadijeh, Vaezi, Ali Reza,

This study was carried out to investigate the role of soil structure in splash erosion in semi-arid soils. Splash erosion was measured in four soil textures (silty clay loam, sandy clay loam, silt loam and sandy loam) with two soil structure conditions (with natural structure and under aggregate breakdown) using a simulated rainfall with 50 mmh-1 in intensity for 30 min in splash caps with 10-c...

ژورنال: آبخیزداری ایران 2021

The process of splash of soil particles by raindrops and their transport by splash or surface shallow flow is considered as interrill erosion, which can reduce soil fertility and cause pollution of surface water. This research was carried out to investigate the temporal variation of interrill erosion in different soils affected by surface slope. For this purpose, laboratory experiments were car...

Journal: :تحقیقات اقتصاد و توسعه کشاورزی ایران 0
معصومه نصیری دانشجوی کارشناسی ارشد دانشگاه علوم کشاورزی و منابع طبیعی گرگان علی نحفی نژاد استادیار گروه آبخیزداری دانشگاه علوم کشاورزی و منابع طبیعی دانشگاه گرگان علی دریجانی استادیار گروه مهندسی اقتصاد کشاورزی دانشگاه علوم کشاورزی و منابع طبیعی دانشگاه گرگان امیر سعدالدین استادیار گروه آبخیزداری دانشگاه علوم کشاورزی و منابع طبیعی دانشگاه گرگان

nowadays soil erosion is considered as a serious threat to human's life and his welfare. when soil erosion not properly controlled, the fertility would gradually decrease. adoption of appropriate soil conservation practices along with socio-economic factors' assessment can be used to increase farmers' awareness and acceptance of soil conservation, and to diminish soil erosion dam...

2000
Evah W. Murage Nancy K. Karanja Paul C. Smithson Paul L. Woomer

Food security in the East African Highlands is dependent upon the productivity of lands managed by smallholders who face difficult challenges in maintaining the fertility of their soils. A study was conducted to identify indicators of soil fertility status that are consistent with farmers’ perceptions of soil fertility. Physical, chemical and biological properties of soils were measured from pa...

Journal: :The Science of the total environment 2006
N Mainville J Webb M Lucotte R Davidson O Betancourt E Cueva D Mergler

Soil erosion and degradation provoked by deforestation in the Amazon is a global concern, and recent studies propose a link between deforestation, soil erosion and the leaching of naturally occurring mercury (Hg). In the Ecuadorian Amazon, elevated deforestation rates and the proximity of volcanoes could play an important role in soil fertility and soil Hg levels. The goal of this study is to e...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه اصفهان - دانشکده زبانهای خارجی 1390

apart from other aspects, desert is a natural environment and is one of the appealing terrestrial elements. putting its symbolic and fictional senses aside, the term “desert” bears mystic sense more than material sense. in addition to the worlds materialistic experiences, desert has attracted the attention of writers because it creates a kind of inner experience, which returns the individual in...

Journal: :International Journal of Geographical Information Science 2007
W. Siyuan L. Jingshi Y. Cunjian

This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date...

2015

Agriculture, the main sector of the Ethiopian economy, accounts for 85% of total employment and is the backbone and mainstay of the economy (Pausewang et al., 1990). However, agricultural productivity is decreasing because of land degradation, particularly due to soil erosion. Hurni (1988) estimated that the extent of erosion from arable land in the highlands of Ethiopia averaged 42 tons/ha/yr....

2015
Chongfeng Bu Shufang Wu Fengpeng Han Yongsheng Yang Jie Meng Wenping Yuan

Biological soil crusts (BSCs, or biocrusts) have important positive ecological functions such as erosion control and soil fertility improvement, and they may also have negative effects on soil moisture in some cases. Simultaneous discussions of the two-sided impacts of BSCs are key to the rational use of this resource. This study focused on the contribution of BSCs while combining with specific...

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