Irrigation and Drainage最新文献

Drought is a serious threat to crop growth, and finding new irrigation methods can save water. This study was conducted to investigate water use efficiency and seed yield in mung bean under wick irrigation. Irrigation treatments consisted of the wick irrigation method, surface irrigation (common irrigation) with water equivalent to wick irrigation, and surface irrigation with the double water use of wick irrigation. The results showed that the wick irrigation had a seed weight per plant, 100-seed weight, seed number per pod, pod number per plant, seed yield, biological yield, water use efficiency of seed, water use efficiency of biomass and net income increase of 164, 14, 28, 80, 164, 128, 164, 128 and 300%, respectively, compared to surface irrigation with an equivalent water volume of wick irrigation. Wick irrigation resulted in increases in plant height, internode length, leaf number per plant, node number per plant, branch number per plant, leaf length and leaf width of 60, 59, 65, 91, 91, 52 and 52%, respectively, compared to surface irrigation with an equivalent water volume of wick irrigation. In conclusion, the wick irrigation method, as a new method, can save water and improve seed yield and net income.

Irrigation canals are the main systems that convey water from sources to demand nodes. Their performance is affected by climate change. In this research, the effect of climate change on temperature and precipitation was investigated in the Aghili irrigation network over the base period 1994–2017, and the Aghili east canal performance was consequently assessed. To this end, the climate data were first assessed by the Mann–Kendall test to determine trends. Then, changes in temperature and precipitation were simulated using HadGEM2-ES in the Long Ashton Research Station Weather Generator (LARS-WG) under two representative concentration pathways (RCPs) of 2.6 and 8.5 over the periods 2021–2040 and 2041–2060. CROPWAT8 was used to calculate the crop water requirement and irrigation hydromodule, and the turnout flow in the considered canal was calculated next. Finally, the canal was simulated and assessed. The results showed that the maximum temperature, evapotranspiration and turnout flow increases are 3.7°C, 1.45 mm/day and 39 L/s, respectively, related to the base timescale. Additionally, the adequacy performance decreased to 0.768 from 0.986, leading to a maximum extra water requirement of 15.1 million m³/year in the Aghili east canal under a pessimistic scenario.

The assessment of land suitability is the key to sustained agricultural output. This study evaluates the suitability of land for irrigated sugar cane cultivation and crop water requirements in the Kuraz Irrigation Scheme, Ethiopia. To accomplish this, the geographic information system–analytical hierarchy process (GIS–AHP) tool combination was employed to identify land suitability classes and aid in decision-making using various factors, such as soil pH, texture, temperature, rainfall, land use–land cover and slope. The AquaCrop model simulated the current and future scenarios for biomass, canopy cover, yield, maximum evapotranspiration and evapotranspiration water productivity for sugar cane crops. AquaCrop was calibrated for irrigated sugar cane in the 2015–2016 crop season, and the results showed that most of the study area is highly suitable for sugar cane cultivation. Highly suitable areas cover 28%, moderately suitable areas 38%, marginally suitable areas 21%, and unsuitable areas 13%. The findings indicate the potential for expanding sugar cane cultivation and increasing yields and profits. However, it is crucial to consider the potential environmental degradation caused by water usage and soil degradation resulting from agricultural expansion. Furthermore, the social implications of expanding sugar cane cultivation should also be considered, including labour practices and the possible displacement of local communities.

Recent climatic variations have hindered the potential of irrigation in Sub-Saharan Africa (SSA). This study presents a suitability analysis of irrigable areas for irrigation using spatial techniques. The focus of this paper was to examine regions that may be viable for irrigation for four small reservoirs constructed under the ‘One Village One Dam’ (1V1D) initiative. The thematic factors used were distance to water, soil type, soil depth, slope, pH, electrical conductivity, hydraulic conductivity, land use–land cover, organic carbon and organic matter. The land cover was classified using high-resolution imagery from SAS Planet because of the small land size. The pairwise ranking found soil type to have an overall higher weight of approximately 15% and electrical conductivity to have the lowest weight. The highly suitable areas were found very close to the dam, and the permanently not suitable areas were located at the far end of the dam. From the area computation, it was found that the highly suitable regions in Kataa, Degri, Napaadi and Zansibulga were 10.52, 55.41, 1.01 and 3.77 ha, respectively. In conclusion, it was found that the majority of irrigable land was within the marginally to highly suitable class.

Natural and socio-economic development under climate change has affected the distribution of surface water resources (SWRs) in many deltas worldwide. The dynamics in the SWRs has negatively impacted agricultural production, which is one of the growing issues in the Vietnamese Mekong Delta (VMD) as the national rice bowl. Our study aims to assess SWR dynamics related to its effects on rice production in the upper VMD. We applied Mann–Kendall, linear regression and Pettit tests to statistically determine trends of SWRs in terms of water level, total water volume and rainfall in 1996–2020. The findings show that high water level trends decrease significantly after 2011, and this reduction has been due to climate variability and dam development upstream of the Mekong River. Moreover, rice yield data analysis from 1996 to 2020 indicated a decreasing trend in the yield of the winter–spring rice crop in the An Phu district of An Giang Province after 2011. Our interviews with 33 water experts and 90 local farmers revealed 80% agreement that the decline in water resources has affected rice yield. This study provides empirical evidence and a platform for knowledge sharing and learning across different deltas and initiatives worldwide.

The irrigated perimeter of Jaíba-MG is located in a semi-arid region of Brazil, which makes irrigation practices necessary in order to guarantee agricultural production. This need occurs in the context of limited water resources and, therefore, it is necessary to study ways to optimize water use efficiency (WUE). For this, it is necessary to obtain local and precise estimates of the crop coefficient (K_c) and the reference evapotranspiration (ET₀). The objective of this study was to evaluate the water requirements and WUE of banana, lemon and mango crops in the irrigated perimeter region of Jaíba using satellite images and meteorological data. Landsat 8 satellite images from 2020 and 2021 were used to estimate the local K_c of these crops. Three methodologies for estimating local K_c were adopted: METRIC, NDVI and NDVI 2. The K_c NDVI method stood out when compared with the standard method (FAO Bulletin 56), with RMSEs of 0.11, 0.16 and 0.20 for banana, lemon and mango, respectively, showing the potential of this methodology. The overall average WUE values for banana, lemon and mango crops were 2.19, 1.58 and 1.58 kg m⁻³, respectively. The results could allow important advances in water management for fruit crops under semi-arid conditions.

Biochar application, as a kind of soil amendment, significantly influences soil physical and mechanical properties. This study revealed the effects of biochar application on the physical and mechanical properties of a clay-type soil at different irrigation levels. Soil was treated with three levels of biochar application: B0 (0 t ha⁻¹), B1 (25 t ha⁻¹) and B2 (50 t ha⁻¹), and three levels of irrigation: T0 (1.2 pan evaporation E_p), T1 (1.0 E_p) and T2 (0.8 E_p). The results indicated that other treatments reduced the soil bulk density compared with the control treatment (CK) (B0T1). Compared to CK, the highest reduction in soil bulk density was 18%. Irrigation did not improve the soil bulk density and porosity at the same biochar application in the short term. Biochar enhanced the stability of the soil aggregates. Compared to CK, the largest MWD (mean weight diameter) was enhanced by 9%. The addition of biochar and decreasing irrigation could decrease soil cohesion. The addition of biochar and increasing irrigation could increase the soil internal friction angle. The soil cohesion first increased and then decreased as the soil water content increased. According to the fitting formula, the soil cohesion was found to be minimum at B2T2, which was a decrease of 39% compared to B0T1. At the same irrigation level, the soil internal friction angle decreased with increasing soil water content. Soil penetration resistance showed a decreasing trend with the application of biochar. The more irrigation there is, the larger the soil penetration resistance.

This paper proposes a new methodology for investigating water management options in agricultural irrigation that accounts for the heterogeneity of irrigation system characteristics and limitations in existing water resources. The process uses a random data matching method to obtain operational management methods and system features using remote sensing data and water resource management optimization to evaluate different management methods. Regional modelling was performed, using the SWAP model under deterministic–stochastic conditions. Inputs such as sowing dates, irrigation procedures, soil characteristics, groundwater depth and water quality were treated as distributed data. To estimate these data, residual minimization was used between the field-scale evapotranspiration distributions modelled in the SWAP model and two Landsat 8 ETM+ images, as well as the Surface Energy Balance Algorithm for Land (SEBAL). The investigation of water management methods using distributed data as input was performed, and optimization of water management and data assimilation was achieved by applying the improved coyote algorithm. The case study was conducted in Mashhad during the dry season of 2018–2019. The results suggest that simultaneous consideration of crop and water management methods, rather than an independent evaluation, can lead to further improvement in regional wheat yield under water shortage conditions.

This study examined the existing cropping patterns, yield, irrigation water and energy use and carbon emission responses to explore the best cropping pattern based on the optimum water–energy–food and carbon emission nexus. The study consisted of field visits, questionnaire surveys among 510 farmers, 10 key informant interviews, one focused group discussion and subsequent analysis of collected data. The result of the research indicated that the best existing cropping pattern was rice–wheat–no crops with a net benefit of USD 491 ha⁻¹, benefit–cost ratio: 1.33, water use: 8830 m³ ha⁻¹, energy use: 43 GJ ha⁻¹ and carbon emission: 2420 kg CO₂-eq ha⁻¹. This study found spring rice to be the most appropriate agricultural commodity in the third season of the crop calendar and rice–wheat–spring rice, as the recommended cropping pattern in the selected area based on maximum production: 13.3 t ha⁻¹, the largest net income: USD 668 ha⁻¹, the highest benefit-cost ratio: 1.27 and the least use of energy 802 GJ ha⁻¹ with release of

3840 kg CO₂-eq ha⁻¹ of carbon. After applying the recommended cropping pattern of this study, there will be significant growth in the benefit per unit use of water and energy and a substantial reduction in carbon emission per tonne of food production.

This study numerically investigated the lining effect on the discharges and seepage losses of five reaches which belong to the El-Sont Canal, Asyut, Egypt, using FLOW-3D and Slide2 models, respectively. Two lining materials were considered, cement concrete (CC) and CC with low-density polyethylene (LDPE) film. A cost analysis was performed to explore the feasibility of the proposed lining materials. Moreover, a parametric study was conducted by the Slide2 model to investigate the effect of canal geometry and liner properties on seepage losses. An artificial neural network (ANN) model was developed based on the Slide2 model scenarios to estimate the seepage losses from lined irrigation canals. The results showed that reach the discharge calculated from the FLOW-3D model increased by 92%–97% and 149%–156%, while the calculated seepage losses from the Slide2 model decreased by 81%–87% and approximately 97% under CC and CC with LDPE film liners, respectively. Cost analysis revealed that the overall cost of CC with LDPE film was higher by 14% than CC. Relying on the importance of saving irrigation water and conveying water to the last reaches, CC with LDPE film is recommended for lining irrigation canals. A parametric study showed that the seepage losses were reduced by more than 96% when the ratio between liner and soil hydraulic conductivities was less than 0.01. A thick liner could maximally decrease the seepage losses by 68%, regardless of the canal geometry. As the developed ANN model showed a close agreement with the Slide2 results with coefficient of determination (R²) and mean squared error values of 0.99 and 0.05, respectively, the ANN model is recommended as a robust and rapid tool for estimating seepage losses from lined irrigation canals.