نتایج جستجو برای: the ratio of land under crop rotation to land under cultivation

تعداد نتایج: 23563731  

Journal: :journal of agricultural science and technology 2014
w. mohammad s. a. shah s. shahzadi kh. haroon

crop productivity, water use efficiency (wue), and microbial biomass c and n in rainfed dry area are influenced by tillage, rotation, and crop residue management. field experiments were conducted during 2005-08 to study the effect of tillage, crop rotation, and crop residue retention on oat fodder yield, water use efficiency, and microbial biomass c (mbc) and n (mbn) under semi-arid conditions ...

Journal: :Plant physiology 2004
Wallace E Huffman

As the demand for food and fiber grew during the past 300 years, because of the Earth’s expanding human population and rising per capita incomes, society met this demand first by increasing the land area under cultivation and later by improving crops so that their yields were higher. Before 1900, land was abundant almost everywhere, and in the United States, new lands were brought into producti...

C.M. Jiang H. Zhou Q. Ma W.T. Yu, Y.G. Xu Y.L. Wang

Long-term yield performance and yield stability of common cropping systems needs to be simultaneously assessed at various fertility regimes. Based on a consecutive 19-year field trial, including eight fertilization treatments with different combinations of nitrogen (N), phosphorus (P), potassium (K) and recycled manure (RM), the effects of fertilization and crop rotation on corn (Zea mays L.) y...

2013
Xi Yang Nick Paulson Madhu Khanna

This paper analyzes the effect of landowner risk preferences and land quality on the optimal mix of vertically integrated production and contracted production of an energy crop in a region characterized by heterogeneity in landowners’ risk preferences and land quality and with riskiness of returns from both energy crop and conventional crop production. We examine the determinants of the decisio...

ژورنال: علوم آب و خاک 2011
جابر فلاح‌زاده, , محمد‌علی حاج‌عباسی, ,

The salt–affected lands in arid regions of central Iran are characterized by low rainfall, low fertility, high evaporation and salinity. The cultivation of salt–affected lands may have a major influence on soil quality. The aim of this study was to determine the response of soil quality indicators to reclamation and cultivation of salt–affected lands occurring in Abarkooh plain, central Iran. S...

Weeds are a serious problem of chickpea cultivation in rain-fed areas of Iran and economic feasibility of crop production is mostly challenged by the method of control. In this study, two types of weed control strategies which are common in the country, including hand removing and hand removing + mechanical application, were compared with application of general herbicide (Glyphosite) using a sp...

Journal: :Conservation biology : the journal of the Society for Conservation Biology 2013
Richard B Chandler David I King Raul Raudales Richard Trubey Carlin Chandler Víctor Julio Arce Chávez

Two contrasting strategies have been proposed for conserving biological diversity while meeting the increasing demand for agricultural products: land sparing and land sharing production systems. Land sparing involves increasing yield to reduce the amount of land needed for agriculture, whereas land-sharing agricultural practices incorporate elements of native ecosystems into the production syst...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه زنجان - دانشکده علوم انسانی 1390

the main purpose of this study was to investigate any relationship between high school efl teachers metaphorical understandings of their role in class and their self-efficacy beliefs. teachers metaphors were elicited through two different prompts: one picturing what they believed a language teacher should be like in class, and the other demonstrating what they are actually like in class; such...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی خواجه نصیرالدین طوسی - دانشکده علوم 1391

abstract in the present research solution of chalcopyrite in sulfuric acid in hydrometallurgy method using electrochemistry with cyclic voltammetry technique has been investigated. the value of maximum reduction peak current of copper ions represents the measure of solubility. in this research different parameters temperature, potential, potential exert time, chalcopyrite concentration, sulfur...

2003
Wanhong Yang Murat Isik

This paper develops a model to examine the impacts of uncertainty about crop production and irreversibility of program participation on determining land rental payments and least-cost land retirement targeting in the Conservation Reserve Enhancement Program. Results show that under risk aversion only, the marginal cost of abatement and the average land rental payment are less than those under r...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید