Didactic tools for supporting participatory water management in collective irrigation schemes     

Klaartje Vandersypen  Abdoulaye C. T. Keita  Bruno Lidon  Dirk Raes  Jean-Yves Jamin 《Irrigation and Drainage Systems》2008,22(1):103-113

In many irrigation schemes, Water Users Associations (WUAs) acquired the responsibility for water management after withdrawal of the state. Based on the success of some indigenous irrigation schemes, it was assumed that farmers could easily become managers. As decision-making was the exclusive terrain of the governmental agencies that ran the schemes, farmers never gained the necessary experience with water management. Therefore, training of farmers and WUAs on the principles and processes of water management is essential. This paper demonstrates a practical example of training material on water management that incorporates research results on the process of Irrigation Management Transfer and resulting farmers’ water management for the case of the Office du Niger irrigation scheme. The results of the paper explain how input from research was used in the four steps of the construction of training material. These steps are (1) setting the training agenda, (2) selecting and adapting information to be featured, (3) targeting the audience and (4) designing the actual training material. A first validation of the approach and examples of the actual training material were obtained in a workshop uniting all stakeholders.  相似文献   

Tillage and irrigation effects on crop yields and soil properties under the rice-wheat system in the Indian Himalayas     

R. Bhattacharyya  S. Kundu  S.C. Pandey  K.P. Singh  H.S. Gupta 《Agricultural Water Management》2008,95(9):993-1002

Conservation tillage systems generally improve soil organic C (SOC), plant available water capacity (PAWC), aggregation and soil water transmission. A field experiment was conducted for 4 years (2001-2002 to 2004-2005) to study tillage (conventional tillage (CT) and zero tillage (ZT)) systems. The selected irrigation treatments were at four levels (I₁: pre-sowing (PS), I₂: PS + active tillering (AT)/crown root initiation (CRI), I₃: PS + AT/CRI + panicle initiation (PI)/flowering (FL), and I₄: PS + AT/CRI + PI/FL + grain filling (GF)), applied at the critical growth stages on rice (Oryza sativa L.) and wheat (Triticum aestivum L.). Their effects on direct seeded rice productivity and soil properties (SOC and selected physical properties) after rice and wheat harvest were investigated. Soil organic C contents after rice and wheat harvest in the 0-15 cm soil depth were higher under ZT than under CT. Soil organic C increased significantly with I₂ over I₁ for both crops and with I₄ over I₂ for the wheat crop. The PAWC was significantly higher with ZT than CT. Zero tilled and frequently irrigated plots showed enhanced infiltration characteristics (infiltration rate, cumulative infiltration and sorptivity) and saturated hydraulic conductivity. Both direct seeded rice and wheat yields were not significantly different in the plots under ZT and CT. There was a significant increase in both rice and wheat yields in the plots under I₂ over I₁. However, water use efficiency between irrigation treatments was not significantly different. Hence, under direct seeded rice-wheat system in a sandy clay loam soil of the sub-temperate Indian Himalayas, farmers may adopt ZT with two irrigations in each crop for optimum resource conservation.  相似文献   

Performance analysis of pressurized irrigation systems operating on-demand using flow-driven simulation models     

M.J. Calejo 《Agricultural Water Management》2008,95(2):154-162

On-demand pressurized irrigation systems are designed to deliver water with the flow rate and pressure required by the farm irrigation systems, sprinkling or micro-irrigation, and respecting the time, duration and frequency decided by the farmers. Due to the variation in farm demand along the season and the day, a large spatial and temporal variability of flow regimes occurs in these systems, which may affect the performance of the farm systems and the yields of the irrigated crops. Therefore, there is a need to analyse those systems to identify and solve performance problems. In this research, two simulation models for the analysis of irrigation systems operating on-demand, ICARE and AKLA, are used and compared to assess the hydraulic performance of the irrigation network of the Lucefecit Irrigation System, in Southern Portugal. ICARE assesses the global performance of the irrigation system through the indexed characteristic curves, while AKLA provides for the identification of the relative pressure deficit and reliability at every hydrant. Both models adopt a flow-driven analysis approach, performing the analysis for multiple flow regimes. To support the hydraulic characterization of the system and for calibration of the steady-state hydraulic model, field measurements were performed at selected nodes of the network, including four hydrants. The analysis with ICARE does not provide for a sufficient identification of problems. In fact, poor performance is indicated when a few hydrants operate below the minimum pressure set at design. Differently, the analysis with AKLA, applied at the hydrant level, shows that the performance of the Lucefecit system is generally acceptable. AKLA identifies which hydrants operate below the required pressure and, therefore, allows to support any eventual related improvement. Results show that the performance of the system highly improved when changing the piezometric elevation from 260 to 265 m a.s.l. However, this improvement is not sufficient because three hydrants still have high relative pressure deficit and low reliability. Solutions for those hydrants require increasing diameters of network pipes supplying them.  相似文献   

Understanding and managing groundwater and salinity in a tropical conjunctive water use irrigation district   总被引：2，自引：0，他引：2  

Cuan Petheram  Keith L. Bristow  Paul N. Nelson 《Agricultural Water Management》2008,95(10):1167-1179

Agricultural production around the world is increasingly being constrained by hydrological factors—such as over-extraction of groundwater in some locations, rising water tables in others, and worsening groundwater quality in general. One such area is the Lower Burdekin irrigation area in northern tropical Australia, where rising watertable levels and increasing salinity concentrations within alluvial deposits are causing concern. The aim of this study was to improve understanding of the processes driving trends in groundwater quantity and quality in Mona Park, a conjunctive water use irrigation district in the Lower Burdekin. The analysis is intended to enable land and water managers to explore alternative policy and management practices to help support the reversal in current trends, and to improve water table conditions in terms of both water quantity and quality. Key lessons that are applicable to the development of new irrigation schemes in wet-dry tropical regions elsewhere in the world are emphasised.This study demonstrated that simple qualitative methods that link historical developments and observed climatic and hydrological trends can support development of a robust understanding of groundwater behaviour. The results showed that to minimise groundwater accessions in wet-dry tropical regions, a large soil water deficit should be maintained in the unsaturated zone prior to the onset of the wet season to buffer against potentially large wet season recharge events, and that this strategy should be implemented from when irrigation is first commenced. It is very clear that groundwater systems under or down gradient from irrigated areas need to be managed adaptively, such that: (1) timely decisions are made in response to changes in watertable level and groundwater quality; and (2) suitable mechanisms are in place to ensure farmers have the financial incentives and flexibility to respond in the short-term. The work also demonstrated that the establishment of good baseline data prior to irrigation development, and long-term analysis (>30 years) involving various combinations of wet and dry periods, are required in order to build a comprehensive understanding of potential groundwater behaviour and adaptive management needs.  相似文献   

Application of the Analytic Hierarchy Process to irrigation project improvement: Part I. Impacts of irrigation project internal processes on crop yields     

H. Okada  S.W. Styles 《Agricultural Water Management》2008,95(3):199-204

Performance improvement of existing irrigation projects has been a major concern in international irrigation development. Activities for irrigation project improvement usually involve not only infrastructure (hardware) improvement but also changes in management. However, the impact of management improvement on irrigation performance has not been sufficiently verified because, in most cases, (a) irrigation project evaluation is done qualitatively, and (b) management improvement is implemented simultaneously with hardware improvement. Therefore, the impact of management improvement needs to be evaluated quantitatively and separately from hardware. This research attempts to quantify effects of management and hardware improvements on irrigation project performance, using the Analytic Hierarchy Process (AHP). First, an AHP model for irrigation project evaluation was developed by using internal process indicators of the rapid appraisal process. Secondly, the AHP model was applied for scoring 16 irrigation projects dealt with in FAO Water Reports 19. Then, finally, effects of the evaluation factors (e.g. managing entities, hardware, water delivery services) on irrigation project performance were analyzed by changing weights of the evaluation factors and comparing correlations between AHP model scores and crop yields. The research showed the potential and effectiveness of AHP application to irrigation project evaluation. Also, it revealed that the quality of water delivery service had a significant impact on crop production. Analysis through correlation did not imply significant relationships among water delivery services, management and hardware. However, it is inferred from the result that there would be still more room to improve the AHP model toward better evaluation of the irrigation project by adding more internal process indicators to the model.  相似文献   

Agricultural and environmental changes after irrigation management transfer in the Develi Basin,Turkey     

Filiz Dadaser-Celik  Patrick L. Brezonik  Heinz G. Stefan 《Irrigation and Drainage Systems》2008,22(1):47-66

Develi Basin is a semi-arid basin in central Turkey where water sustains both irrigated agriculture and an internationally important wetland, the Sultan Marshes. Agricultural and environmental changes in the Develi Basin have occurred since irrigation management was transferred in 1994 from a state authority (DSI) to irrigation associations (Kovalı and Ağcaaşar IAs). In this paper we evaluate the practices of the IAs using extensive data from interviews with farmers and IA officials, as well as data from reports prepared by DSI and the IAs, using comparisons with case studies reported in the scientific literature. Irrigated areas and surface water use in the Develi Basin showed significant fluctuations from 1995 to 2003. The area allocated to high water-consuming plants increased. Maintenance activities became dependent on fee collection rates. Quality of the irrigation water did not changed significantly. Ground-water levels, flow rates from springs, and water levels in the Sultan Marshes all dropped. Overall analyses indicate that the water requirements of the Sultan Marshes have not been met, while water use for irrigation has been effective but not efficient. To reconcile agricultural and wetland water requirements, a basin-wide approach in water planning is recommended. Amounts of water to be allocated to the IAs and wetlands need to be clearly defined. DSI has to monitor canal maintenance by the IAs more closely, and IAs need to be given more responsibilities for future rehabilitation of the canals. Realistic water pricing, increased reliability of irrigation scheduling, higher on-farm irrigation efficiency, and in the long-term, modernization of the irrigation system need to be considered.  相似文献   

荒漠草原区灌溉和旱作条件下蒙古冰草和新麦草产草量的构成因素   总被引：1，自引：0，他引：1  

海棠  韩国栋  胡跃高 《草地学报》2007,15(3):269-272

对荒漠草原区灌溉和旱作条件下蒙古冰草和新麦草的适应性、单株产草量构成因子及其贡献率进行了研究。结果表明:灌溉条件下蒙古冰草和新麦草单株产草量及其各构成因子产量或数值皆大于旱作条件下;旱作条件下蒙古冰草产草量构成因子对单株产草量的贡献率大小顺序为,茎重>株高>穗重>分蘖数>叶重,新麦草为茎重>分蘖数>株高>叶重>穗重;灌溉条件下蒙古冰草产草量构成因子对单株产草量的贡献率大小顺序为,茎重>分蘖数>株高>穗重>叶重,新麦草为茎重>株高>分蘖数>叶重>穗重。  相似文献   

Sentinel-2多光谱卫星遥感反演植被覆盖下的土壤盐分变化     

杜瑞麒  陈俊英  张智韬  徐洋洋  张兴  殷皓原  杨宁 《农业工程学报》2021,37(17):107-115

为克服植被覆盖条件下土壤盐分含量与光谱反射率之间相关性较差所带来反演精度较低的问题,该研究以内蒙古河套灌区沙壕渠灌域为研究区域,利用Sentinel-2卫星同步获取光谱数据,通过构建以归一化植被指数（Normalized Difference Vegetation Index,NDVI）为分支标准的盐分深度决策树确定反演土壤盐分含量的最佳深度,然后构建以NDVI和表层土壤含水率为分支标准的类别决策树,将土壤样本划分为不同类别,以此分别构建土壤盐分反演模型,并评估反演效果。研究结果表明,决策树能增强光谱反射率对土壤盐分含量的敏感性,光谱反射率与土壤盐分含量的相关系数达0.66以上。基于随机森林（Random Forest,RF）的盐分反演模型可取得理想的反演效果,决定系数为0.77,均方根误差为0.27%,相对分布误差为2.65,相对分析误差为8.99。土壤盐分含量反演模型能较好地反演表层（<20 cm）和深层（>40～60 cm）土壤盐分含量,在反演中层（20～40 cm）土壤盐分含量上存在一定局限。当地表有植被覆盖时,利用决策树可有效地提高土壤盐分含量的反演精度（与未考虑决策树相比,决定系数和相对分布误差分别提高0.34和0.67）。研究结果可为监测灌区内作物生育期间土壤盐分含量的动态变化提供方法参考。  相似文献   

基于无人机遥感数据的生态渠系信息提取   总被引：2，自引：0，他引：2  

张自超  韩宇  陈建  王术波  王广琦  杜楠楠 《排灌机械工程学报》2018,36(10):1006-1011

针对河套灌区引水灌溉中存在粗放型灌溉,且当地为提高产量,仅注重扩大种植面积的问题,提出了一种渠系信息精准提取的方法.基于无人机遥感图像,运用ENVI 5.1软件,对遥感图像进行预处理,对图像RGB3个通道分别进行拉伸显示,经组合以增强其对比度;运用面向对象法进行图像分割,用基于规则的分类方法,基于不同规则进行单独及组合分析,确定了“光谱平均值小于98、最小包围矩形长宽比处于其最小值与0.85之间、延长线大于1 m”的最优组合规则,提取了内蒙古河套灌区某部分生态渠系信息,对于生态渠道的识别精度达到毛沟级,并对提取结果进行了评价,其中组合辅助解译正确率达96.4%,为精准灌溉运行管理提供了较准确的渠系信息.  相似文献   

河套灌区不同地类盐分迁移估算及与地下水埋深的关系   总被引：1，自引：0，他引：1  

王国帅  史海滨  李仙岳  郭珈玮  王维刚  吴迪 《农业机械学报》2020,51(8):255-269

针对河套灌区引水量逐年减少、输入灌区的盐分无法有效排出、仅能在灌区内部重新分配的现状,以河套灌区耕地-荒地-海子为研究对象,通过野外实测和室内试验分析相结合,基于地质统计学、溶质动力学理论,研究了耕地-荒地-海子系统土壤剖面、不同土层盐分和地下水盐分的时空变化特征,定量估算了不同时期的盐分变化,揭示了系统盐分的表观平衡,分析了地下水埋深对土壤盐分的影响。结果表明:在耕地-荒地-海子系统中,灌溉期,耕地大量盐分随地下水迁移到荒地,秋浇前荒地含盐量是耕地的2倍,秋浇后荒地脱盐量是耕地的3倍。整个生育期耕地1 m土体盐分通过灌溉期淋洗,积盐率仍为56%,秋浇后盐分没有完全排出,脱盐率为44%,土壤深层有轻微积盐现象;荒地1 m土体积盐率为63%,秋浇后脱盐率为62%,荒地盐分全年基本保持平衡。地下水和海子盐分时空分布呈条带状,存在较强的空间相似性,海子是系统的储盐区。应采取有效措施将灌区目前地下水埋深降低0.2 m,研究区地下水埋深控制在1.7～2.3 m之间更佳。在生育期(5月15日—9月15日),荒地1 m土体积盐量为377 705 kg/hm~2。地下水补给荒地20～100 cm土壤盐量为17 985 kg/hm~2,占积盐量的5%; 0～20 cm土壤盐量增加202 395 kg/hm~2,占积盐量的54%;耕地地下水迁移给荒地深层土壤盐量为114 015 kg/hm~2,占积盐量的30%;耕地水平渗透给荒地的盐量为43 305 kg/hm~2,占积盐量11%。本研究可为灌区水盐运移提供理论依据。  相似文献