Irrigation and Drainage最新文献

Irrigation development can be an effective economic force for agricultural production, regional development and urban and rural community development. This study estimated the societal economic footprint of the Irrigation Districts on the economy in Alberta, Canada, via a variety of economic impact analysis models. The analysis indicates that producers, agricultural and non-agricultural industries and communities benefit (either directly or indirectly) from irrigation development and related activities. These impacts result from the direct use of irrigation water for crop and livestock production, whereas other impacts are related to irrigation infrastructure (reservoirs and canals) that provides water for municipalities, food processing industries, recreation and wildlife habitat development. Irrigation Districts' direct annual contribution to Alberta's agri-food gross domestic product (GDP), a traditional measure of economic growth, was about $1 billion. This contribution increased, through indirect and induced impacts, to $5.4 billion for the provincial GDP—about 5 times greater than the direct contribution. About 81% of the GDP generated by the Irrigation Districts accrued to the province, and about 19% to the irrigation producers. This study revealed that irrigation development is a beneficial economic strategy for the province, irrigation producers, food processing industries and sustainable community development. This study also demonstrated that economically successful irrigation projects should develop linkages between irrigation producers and regional food processing industries.

Amidst climate change and recurring droughts, increasing irrigation water amount and frequency alone is not a definitive solution to address water scarcity in agricultural crop production, particularly in soils with poor water retention capacity. This study evaluated the effects of two drought adaptation strategies (deficit irrigation and soil amendment) based on data from a pot experiment. The results indicated that the combined use of a soil amendment product with deficit irrigation enhanced the water use efficiency (WUE). Deficit irrigation starting in the midstage combined with the soil amendment product achieved higher water use efficiency (0.24 and 0.32 g/L for spring and winter wheat, respectively). This is considered to be an optimum WUE, as it was attained with a reduced actual evapotranspiration of 3.78 L for spring wheat. In contrast, with full irrigation, a higher WUE of 0.40 g/L was achieved but with approximately double the actual evapotranspiration of 6.10 L. Additionally, the drought coping of wheat was manifested by the stage-wise adjustment of its crop coefficient. In general, the influence of deficit irrigation on the crop coefficient adjustment was more pronounced than the effect of soil amendment was.

ENORASIS has been developed as a real-time smart irrigation decision support and management system consisting of weather forecasting systems based on satellite observations, irrigation optimization techniques and wireless sensor networks. This study revealed that irrigation could be managed with ENORASIS without a significant decrease in efficiency when less water is used (14%–71%) than with the conventional irrigation management approach. Thus, fewer agricultural chemicals are washed away from the soil, but water efficiency increases, leading to the use of less water and groundwater pollution. According to these results, although ENORASIS usually stands out as a recommended irrigation management system in terms of water usage parameters and performance indicators for both cotton and maize, either of the two irrigation management systems could be preferred considering yield, technological and agronomic characteristics. Among these, the choice should be made according to the results of an economic analysis on factors such as time, labour and energy needs for water supply, as well as metered irrigation and pricing in water and irrigation costs. This study revealed that ENORASIS can be used for sustainable irrigation and water resource management.

Clogging represents a critical challenge that undermines the efficiency and sustainability of drip irrigation systems by inducing uneven water distribution and increasing maintenance requirements. In this study, the phenomenon of clogging in drip emitters was investigated via computational fluid dynamics (CFD) in conjunction with the discrete element method (DEM). The original drip (OD) was analysed to pinpoint areas prone to particle accumulation, particularly in regions characterised by low velocity and reduced turbulence kinetic energy, conditions that facilitate particle deposition. The analyses revealed that vortex formation in narrow corners and stagnation zones within the emitter’s flow path primarily contributed to clogging. To address this issue, a modified drip (MD) was proposed, aimed at optimising flow patterns and mitigating vortex development. CFD–DEM simulations of the MD indicated a significant reduction in clogging risk and enhanced particle transport efficiency. At an inlet water velocity of 0.075 ms⁻¹, the MD achieved a 2% higher particle transport rate than did the OD, and similar improvements were noted at higher velocities. These findings underscore the potential of design modifications to enhance system performance and reduce maintenance costs. Future research should further validate the MD under diverse environmental conditions, including variable water qualities and different soil types.

Irrigation water supply is under scrutiny because of dwindling water resources. Most irrigation water in South Africa (SA) is transmitted by canals. Transmission water loss (TWL) accounts for 12% of the irrigation water losses in SA. Therefore, there is a need to investigate and understand the major parameters influencing TWL at Vaalharts Irrigation Scheme (VIS). A study using 39 concrete-lined canal reaches was performed from 2020 to 2022. Water flow measurements and observations of selected environmental parameters with potential influence on TWL were performed on three occasions during the study. The velocity-area method was used to calculate flow rates at the canal reach inlets and outlets. The inflow–outflow approach was used to determine TWL (% per 100 m). The study results revealed that TWL increased significantly (p < 0.05) with decreasing canal size. Canal shape and location had no significant effects on TWL; however, the TWL decreased in the middle zones. Flow-related parameters strongly affected TWL. Environmental parameters also exhibited strong effects. Although the study results elucidate TWL at VIS, further research involving more intense data collection is recommended. The effects of non-physical parameters should also be investigated in future studies. Maintenance should be prioritized in irrigation schemes that use canals.