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Improvement of Water Use Efficiency in Irrigated Agriculture: A Review  [PDF]
Tahar Boutraa
Journal of Agronomy , 2010,
Abstract: Water scarcity and the increasing global demand for water in many sectors, including agriculture, has became a global concern. The rapid growing world population and the adverse impacts of climate change led to growing competition for water use by industrial and urban users for agriculture to secure enough food. Irrigated agriculture is an important role in total agriculture and provides humanity with a wide range of agricultural products, including fruits, vegetables, grains and cereals. Effective management for water use is the only way to save water for the increasing irrigated agriculture. Different approaches have been adopted to reduce the damage caused by drought; among these approaches is water productivity or water use efficiency WUE. A crop with high WUE should have greater yield than a crop with low WUE.
Remote Sensing of Irrigated Agriculture: Opportunities and Challenges  [PDF]
Mutlu Ozdogan,Yang Yang,George Allez,Chelsea Cervantes
Remote Sensing , 2010, DOI: 10.3390/rs2092274
Abstract: Over the last several decades, remote sensing has emerged as an effective tool to monitor irrigated lands over a variety of climatic conditions and locations. The objective of this review, which summarizes the methods and the results of existing remote sensing studies, is to synthesize principle findings and assess the state of the art. We take a taxonomic approach to group studies based on location, scale, inputs, and methods, in an effort to categorize different approaches within a logical framework. We seek to evaluate the ability of remote sensing to provide synoptic and timely coverage of irrigated lands in several spectral regions. We also investigate the value of archived data that enable comparison of images through time. This overview of the studies to date indicates that remote sensing-based monitoring of irrigation is at an intermediate stage of development at local scales. For instance, there is overwhelming consensus on the efficacy of vegetation indices in identifying irrigated fields. Also, single date imagery, acquired at peak growing season, may suffice to identify irrigated lands, although to multi-date image data are necessary for improved classification and to distinguish different crop types. At local scales, the mapping of irrigated lands with remote sensing is also strongly affected by the timing of image acquisition and the number of images used. At the regional and global scales, on the other hand, remote sensing has not been fully operational, as methods that work in one place and time are not necessarily transferable to other locations and periods. Thus, at larger scales, more work is required to indentify the best spectral indices, best time periods, and best classification methods under different climatological and cultural environments. Existing studies at regional scales also establish the fact that both remote sensing and national statistical approaches require further refinement with a substantial investment of time and resources for ground-truthing. An additional challenge in mapping irrigation across large areas occurs in fragmented landscapes with small irrigated and cultivated fields, where the spatial scale of observations is pitted against the need for high frequency temporal acquisitions. Finally, this review identifies passive and active microwave observations, advanced image classification methods, and data fusion including optical and radar sensors or with information from sources with multiple spatial and temporal characteristics as key areas where additional research is needed.
MAHARASHTRA NON-IRRIGATED AREAAND AGRICULTURE
M.B. WAGHMODE AND V.V. PAWAR
Indian Streams Research Journal , 2012,
Abstract: Irrigation is a prerequisite for adopting the new technology in the use of cultivable land cultivated land is the area regularly ploughed and includes both tillage and follows land. Irrigation leads to better productive use of cultivated land. To be successful and well developed agriculture requires supply of water at regular interval and required quantities. The transformation partly or fully depends upon the nature and mode of irrigation; hence it is regarded as an integrated part of sound infrastructure of agriculture.
Institutional Aspects of Sustainability for Irrigated Agriculture in Arid and Semi-Arid Regions
del Callejo,Iván; Cossío,Vladimir;
Chilean journal of agricultural research , 2009, DOI: 10.4067/S0718-58392009000500005
Abstract: concerns, arguments, and approaches to sustainability are exposed in both scientific and technical irrigation literature which is based on the priority of food production and water preservation as a basic resource. different approaches related to sustainable irrigated agriculture are identified beyond the technical considerations of irrigation as dealt with by very specialized scientific literature. these focus on socio-economic and institutional aspects of irrigation management. in this chapter, four main approaches are discussed: ?new institutionalism? is an approach which emphasizes economic and financial issues such as cost recovery and the role of the market in water rights reallocation. a second approach, ?common pool resources management? highlights the role of local organizations and institutions with respect to collective water management, and the possibilities to design ?robust institutions? considering the involvement of different stakeholders, not only (state) authorities. a third is identified as the ?empowerment approach?. in this approach, topics such as power relations, autonomy, gender relations, as well as water rights and access are considered as key elements configuring water management practices in irrigation systems. finally, there is the ?post-institutional approach?. it outlines concepts such as ?institutional bricolage?, uncertainty, and legal pluralism used as analytical elements to understand the dynamics and complexities of irrigation development. in conclusion, different levels to analyze sustainability are discussed from an institutional perspective by identifying key knowledge gaps and the need to integrate some of the elements found in the different approaches.
Application of Stochastic Production Frontier in the Estimation of Technical Efficiency of Irrigated Agriculture in Tunisia
Tawfik Ben Amor,Christophe Muller
Agricultural Journal , 2013, DOI: 10.3923/aj.2010.50.56
Abstract: In this study, we estimate agricultural technology for Tunisian peasants, accounting for the crop choice of perasants and distinguishing inputs for individual crops such as: vegetable farming cereal and fruit-trees. The study employed the use of cross-section data from distinguishable irrigated crops survey conducted on a sample of 218 farmers frome 11 regions in Tunisia. The data were collected with the aid of structured questionnaire and were later analysed. The Cobb Douglass production frontier model is employed in order to analyse data collected. Among the irrigated crop farmers, the significant variables were: farmuar manuar fertiliser quantity, labor, mecanic traction and among of irrigated water applied. The estimated sigma square (σ2) and gamma (γ) are widely significants for all irrigated crops and revealed that >85% of the variation in the Tunisian irrigated output among farmers in the study area are due to the differences in their efficiencies. Howerver, we find that predicted technical efficiency widely varies across farms and crops from an average of 54.7% for vegetable farming up to 80.6% for fruit-trees. The study also revealed the existing on inefficiency effects among the farmers as: education, farmer s age, irrigation techniques, lack of education, property of land.
Water supply and demand in the lower Río Bravo/Río Grande basin: The irrigated agriculture scenario
José Návar
Geofísica internacional , 2004,
Abstract: Conventional management of water resources cannot sustain development in the lower Río Bravo/Río Grande watershed. Long-term projections of water supply and demand provide information to plan for the sustainable management of water resources. Four scenarios were studied to project water availability and supply on the Mexican side of the Lower Río Bravo/Río Grande watershed: (i) water development of the Conchos River, (ii) drought spells on record, (iii) normal hydrological conditions, and (iv) the simultaneous presence of (i) and (ii). The size of agricultural lands could become more variable, with loss of irrigated agriculture in district 025 of the Mexican lower Río Bravo/Río Grande, due to increasing water demand from domestic, industrial, commercial, and municipal sectors in the municipalities bordering the Río Bravo/Río Grande, magnified by drought and the development of water demand of the Conchos river.
Computational modeling for irrigated agriculture planning. Part I: general description and linear programming
Borges Júnior, Jo?o C. F.;Ferreira, Paulo A.;Andrade, Camilo L. T.;Hedden-Dunkhorst, Bettina;
Engenharia Agrícola , 2008, DOI: 10.1590/S0100-69162008000300008
Abstract: linear programming models are effective tools to support initial or periodic planning of agricultural enterprises, requiring, however, technical coefficients that can be determined using computer simulation models. this paper, presented in two parts, deals with the development, application and tests of a methodology and of a computational modeling tool to support planning of irrigated agriculture activities. part i aimed at the development and application, including sensitivity analysis, of a multiyear linear programming model to optimize the financial return and water use, at farm level for jaíba irrigation scheme, minas gerais state, brazil, using data on crop irrigation requirement and yield, obtained from previous simulation with mcid model. the linear programming model outputted a crop pattern to which a maximum total net present value of r$ 372,723.00 for the four years period, was obtained. constraints on monthly water availability, labor, land and production were critical in the optimal solution. in relation to the water use optimization, it was verified that an expressive reductions on the irrigation requirements may be achieved by small reductions on the maximum total net present value.
INTEGRATING LOCAL KNOWLEDGE AND LOCAL INNOVATION WITH DEVELOPMENT POLICIES FOR A SUSTAINABLE AGRICULTURE  [PDF]
Mircea Grigora?
Journal of Central European Agriculture , 2009,
Abstract: This article aims to underline the necessity to integrate local knowledge into the development policies in the fi eld of sustainable agriculture. The basic idea is that we need to apply our local knowledge to the fundamental redesign of our technologies and systems in order to be able to bridge the current gap between research and local economy.
Driving Forces of Land Use Changes in Irrigated Agriculture
灌区土地利用变化驱动因素分析——以内蒙古河套灌区为例

ZHANG Yin-hui,LUO Yi,LIU Ji-yuan,ZHUANG Da-fang,
张银辉
,罗毅,刘纪远,庄大方

资源科学 , 2006,
Abstract: Land use/cover change and its driving force have become the hot topic of geographers and ecologists within recent years.Study areas involved cities,towns,deserts and oasis,while less attention was paid to irrigated agriculture.More attention was paid to water-saving irrigation,pollution and canal system modification in irrigated agriculture.In fact,study on land use/cover change and its driving forces in irrigated agriculture have an important theoretical significance.In irrigated agriculture,canal system and soil types have an important impact on land use change.Hetao irrigated agriculture in Inner Mongolia was taken as a case study and the impact of irrigation canal distribution and soil type on land use pattern change was analyzed based on GIS technology.The mean distance to irrigation canal of each land use type and area percentage of different land use type on different soil types was computed with the support of GIS software ArcINFO and ArcView.It is found that the area of alkali-saline land increases near the irrigation canal while the area of farmland declines and wasted grassland increases in the areas far from the canal system.The former is mainly due to elevated groundwater level with long time irrigation and poor drainage system and the latter is mainly caused by limited water resources.Poor soil quality with long time tillage and no rational conservation practice cause some farmland degraded to wasted grassland and alkali-saline land.Land use/cover change and driving forces in Hetao irrigated agriculture are complicated,and it is a product of human activities and natural forces in a long-time period.In further study,water diversion form the Yellow River,groundwater level materials,natural factor including temperature and precipitation,social factors including population,economy and government regulation and factors mentioned above should be analyzed by synthesis method to better understand land use dynamics and promote sustainable development in Hetao irrigated agriculture.
Irrigated Agriculture Monitoring by Geographic Information System (GIS) and Remote Sensing (RS) Techniques for Southern Part of Indus Basin (Sindh Province, Pakistan)
Z.H. Maik,Ir. A.M. van Lieshout,S.K. Agha,G.M. Channar
Journal of Applied Sciences , 2003,
Abstract: The rapid growth of population has put a severe strain on soil and water resources in developing countries. Due to lack of proper planning and the shortage in extension service in the agricultural sector, where the major part of water supply is needed, farmers compete in searching for water resources. Thus in this water competition arena, where water is needed for agriculture, industrial, domestic and other needs, irrigation water management is very essential. The irrigation water management is very complex in especially for vast regions, such as Indus Basin 16 million ha wide. Therefore, in addition to present traditional methods of water management, new modern techniques also required to solve the problems for the river basins. As compared to traditional methods, the management practice of irrigated agricultural land by GIS and remote sensing techniques has evident advantage as objectivity, time-saving, low costs and a lot of auxiliary information can be obtained at the same time. GIS/RS techniques are used to monitor Irrigated Agriculture for southern part of Indus (Sindh Province). The screen digitizing method is used to digitize map of Sindh Province. The NDVI is estimated from NOAA-AVHRR satellite data for both kharif and rabi seasons, the agriculture and non-agriculture areas are identified. This will certainly lead to know the uses of water for agriculture and non-agricultural ecosystem in river basins and also proper allocation/distribution of water at different growing stages.
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