Irrigation and Drainage最新文献

The use of the system of rice intensification (SRI), deficit irrigation and foliar fertilizer application has proven to be effective in enhancing water productivity (WP) individually. However, information on their combined effects is limited. Therefore, this study evaluated the effects of integrating deficit irrigation and carbonate foliar fertilizer (Lithovit) application into the SRI on WP. This study was conducted under the Mkindo Irrigation Scheme in Mvomero, Morogoro, Tanzania, during the dry and wet seasons (October 2020 to June 2021). The experiment was laid out in a split-plot design with three levels of irrigation for the main plots, which were 100% of the irrigation water requirement (40 mm) imitating the SRI alternate wetting and drying pattern and induced deficit irrigation applied at 80% and 50% of the irrigation water requirement as IR₁₀₀, IR₈₀ and IR₅₀, respectively. In addition, there were five subplot fertilizer treatments: (A) diammonium phosphate (DAP) and urea (normal practice); (B) DAP, urea and 100% of the recommended foliar fertilizer (Lithovit standard); (C) DAP, 50% (Lithovit and urea); (D) Lithovit standard only; and (E) no fertilizer. The combined irrigation and fertilizer treatments tested were IR100A, IR100B, IR100C, IR100D, IR100E, IR80A, IR80B, IR80C, IR80D, IR80E, IR50A, IR50B, IR50C, IR50D and IR50E. The highest and lowest WP were 0.851 kg/m³ and 0.562 kg/m³ for IR₈₀B and IR₈₀E, respectively, for the dry season. For the wet season, the highest and lowest WP were 0.540 kg/m³ and 0.306 kg/m³ for IR₅₀B and IR₅₀E, respectively. WP is attributed to the SRI and Lithovit, which act as long-term reservoirs for carbon dioxide, especially during water stress periods. Thus, integrating deficit irrigation and carbonate foliar fertilizers improves WP in rice cultivation. This study demonstrated that this approach can lead to significant water savings while improving rice yields. This integrated approach can be adapted and optimized based on the specific conditions and requirements of different agroecological contexts.

The area under irrigation in Malawi has increased, but productivity is still low due to farmers' lack of irrigation knowledge. This paper describes a ‘people-centred learning’ approach aimed at improving water management in smallholder irrigation schemes. The work was conducted in Malawi, where farmers at the Bwanje, Tadala, Nanzolo and Matabwa irrigation schemes were provided with soil water sensors that showed whether the soil was wet, moist or dry using colours, making it easy for farmers to understand. Indicators related to water management and soil water status were monitored during the 2017 and 2018 irrigation seasons. The yield and gross margins were then assessed. The results show that farmers can effectively identify irrigation-related problems and act on the information provided by the tools. The yield increased by more than 80%, and the gross margins increased by more than threefold across all the schemes. Based on the findings outlined, the use of soil water sensors enhances farmers' understanding of water management, prompting behavioural changes and measurable improvements in irrigation productivity. Furthermore, this study concludes that improving farmers' knowledge is essential for transforming smallholder irrigation schemes into profitable and sustainable investments.

The chemical clogging of water drips is the main obstacle to the adoption and spread of microirrigation technology. The aim of this research is to understand the scaling phenomenon by identifying the substances responsible for emitter clogging using a combination of different methods of characterization and to investigate the effectiveness of a new product ‘Melacide P/2’ as a calcium carbonate scale inhibitor. A non-electrochemical method from the Laboratory of Chemistry and Genie of the Environment (LCGE) was employed to investigate the effect of the inhibitor against calcium carbonate precipitation at 25°C. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study the effect of Melacide P/2 on the scale morphology and crystalline phases. Density functional theory (DFT) and Monte Carlo (MC) simulations were performed to support the experimental results. Characterization techniques revealed that the scale recovered from the drips consisted mainly of calcium carbonate, a variety of calcite. The experimental data indicate the likelihood of preventing calcium carbonate precipitation after the addition of a very small amount (0.30 mg L⁻¹) of Melacide P/2 under the conditions of the experiment. XRD and SEM revealed that the inhibitor tested has the potential to disrupt or block regular CaCO₃ crystal growth and transform a more stable and adherent scale of calcite to aragonite, which is easy to eliminate. The theoretical approach adopted supports the experimental findings. Therefore, Melacide P/2 could be used as a cost-effective green-scale inhibitor to protect microirrigation systems from unwanted scale formation.

Guiding environmental regulation plays a crucial role in the implementation of village-level river chief policies, and it is important to explore how guiding environmental regulations affect the policy implementation capacity of village-level river chiefs. This study focuses on village-level river chiefs as the research subjects and aims to measure the intensity of environmental regulation guidance from their own perspective. By combining theoretical analysis and empirical research, we delve into the effects of guiding environmental regulations on the policy implementation capacity of village-level river chiefs. Our findings demonstrate a significant positive impact of guiding environmental regulations on the policy implementation capacity of village-level river chiefs. Mechanism analysis reveals that environmental cognition, technical cognition and institutional trust play mediating roles in the relationship between guiding environmental regulations and policy implementation capacity. Furthermore, heterogeneity analysis at the village level indicates that the impact of guiding environmental regulations on policy implementation capacity is more pronounced in the western region, where villages have a shorter establishment time of the river chief system and have a greater number of non-governmental river chiefs. At the individual level, heterogeneity analysis reveals that the impact of guiding environmental regulations on policy implementation capacity is more significant among individuals in lower education groups and those serving as representatives in the people's congress. Based on our research findings, this paper proposes countermeasures and suggestions to enhance the effectiveness of guiding environmental regulations. These include formulating scientific and reasonable guiding environmental regulation requirements, providing village-level river chiefs with enhanced governance resources, and emphasizing the mediating roles of environmental cognition, technical understanding and institutional trust. Additionally, we highlight the importance of enhancing the pertinence and universality of the specific content of guiding environmental regulations.

Integrating surface and groundwater use is a crucial part of water management. When one type of water is depleted, the other follows suit because of the constant movement and interaction between them. Therefore, the primary objective of this research is to establish a method by which the water evaluation and planning system (WEAP) surface water model and the MODFLOW groundwater model can communicate with one another. This article aims to demonstrate the interdependence of groundwater and surface water. Here, we use MODFLOW to model the saturated soil region and the soil moisture method to model the unsaturated soil region. The interaction between surface water and groundwater will affect the region's water resources and how they will operate under the continuance of existing practices. The simulation of saturated and unsaturated soil zones using a connected model of surface and groundwater employing all the hydroclimatology balance components is one of the most significant accomplishments of this research. The findings show that the (Iran) Sonqor Plain's maximum aquifer recharge throughout the months of November to May during a period of 30 years (October 1991 to September 2020) ranges between 1.5 and 2.6 million m³. A lack of recharge from irrigation water infiltration occurs in some of these months in addition to rain. The highest rate of groundwater level increase in this area is 4.5 m yr⁻¹ as a result of the distribution of irrigation water provided from the dam in the north-western region.

An orthogonal experiment with three factors and three levels was conducted to study the seepage rate and uniformity of stalk composite pipe (SCP) under subsurface SCP irrigation (SSI). Furthermore, to determine the best application mode for SSI, the pipeline length, irrigation volume and inner–outer diameter of the SCP were considered at a 0.4 m working pressure. The three levels corresponding to each factor were 20, 40 and 60 m; 30, 45 and 60 L m⁻¹; and 28–60, 40–80 and 50–100 mm, respectively. The results indicated that the seepage rate gradually decreased with increasing pipeline length. The pattern of the change in the seepage rate with irrigation volume was not obvious. There was a positive correlation between the seepage rate and the inner–outer diameter of the SCP. The irrigation uniformity coefficient, which was calculated based on the width of the surface wetting front, gradually decreased with increasing pipeline length. The impact patterns of irrigation volume and inner–outer diameter on irrigation uniformity were ambiguous. The seepage rate reached its maximum at the pipeline length, irrigation volume and inner–outer diameter, which were 20 m, 30 L m⁻¹ and 50–100 mm, respectively. There was the highest irrigation uniformity, with a pipeline length, irrigation volume and inner–outer diameter of the SCP of 20 m, 60 L m⁻¹ and 40–80 mm, respectively.

Drought management in the agricultural sector requires monitoring and prediction of this phenomenon, as well as providing a suitable cropping pattern. In this study, the reconnaissance drought index (RDI) was used for drought monitoring in Fars Province, Iran. The status of water resources was predicted using a model that matches the time series of the RDI and the groundwater level. The optimal cropping pattern was obtained according to the predicted available water resources using a genetic algorithm. Generally, the actual and predicted changes in groundwater levels indicate the critical conditions of groundwater resources in the study area. Groundwater resource consumption should be lowered by implementing deficit irrigation scenarios that result in keeping crops with lower sensitivity to water deficit in cropping patterns such as barley, wheat, canola, forage corn and potato. The cropping pattern optimization results suggest an increase in the area allocated to more economical crops in the northern half of Fars Province due to the better temporal distribution of annual rainfall and better water resource conditions. However, with increasing water costs, the cultivation area and the optimal water reduction fraction of these plants decreased.

Using tapes in drip irrigation is associated with environmental problems due to the accumulation of tapes in agricultural areas. Farmers either leave them on the fields or burn them or bury them. All three of these methods pose dangerous environmental hazards. To address this issue, it is recommended that these materials be produced from or with biodegradable materials. In this study, a biodegradable additive was used as a degradation accelerator in the production of tapes. After the production of these tapes, they were used under real conditions and during a growing season and in two treatments: below and on the soil surface, along with a canopy and without shade (beans and radishes). After 6 and 11 months, the tapes were sampled to investigate their degradation. The results showed that tapes made with oxo as an additive began to degrade more quickly than did conventional tapes. A reduction in properties such as weight (p < 0.05), turbidity (p < 0.05), and mechanical properties such as tensile strength at the rupture point (p < 0.05), elongation at the rupture point (p > 0.05), Young's modulus (p < 0.05) and toughness (p < 0.05) in tapes produced with oxo additives shows more and faster degradation than conventional tapes. Therefore, the use of oxo master batches in the production of tapes is possible and useful.

The Imamoğlu Agricultural Irrigation Automation Project aims to revolutionize water management and allocation in agricultural irrigation through the establishment of a central management-based system. By integrating modern irrigation technologies and systems, the project seeks to optimize water usage by monitoring key variables such as irrigation methods and plant–water–yield relationships. The electronic water management system (ESYS), at the core of this initiative, employs a geographic information system (GIS)-based interface and real-time data to facilitate active participation of farmers and water stakeholders. Through the utilization of deep learning technology and real-time data analysis, the system enables timely and informed irrigation planning, resulting in significant water savings and increased productivity. The project's implementation, focused on the Imamoğlu Irrigation System, has gradually introduced a remote central management-based agricultural irrigation automation system to 2,240 farmers. Integrated with the ESYS, this system offers benefits including enhanced water supply security, remote access to irrigation control, soil moisture monitoring, weather-based irrigation planning and centralized plant pattern management. The project aims to promote efficient water usage, maximize food production and serve as a model for future irrigation projects. Key highlights include up to 65%–70% increase in water savings, up to 90% reduction in energy and fuel savings, up to 90% reduction in labour and personnel savings and more efficient irrigation management, among others.

The objective of this study was to evaluate growth and development in an irrigated forage cactus–sorghum intercropping system under different strategies for improving agricultural resilience. The research was carried out from 2018 to 2020 in Serra Talhada, Pernambuco, Brazil, in four experiments in a randomized block design, each with four replications. The first experiment consisted of different configurations for the cactus–sorghum intercropping system (Orelha de Elefante Mexicana [OEM]-single crop [SNG], IPA Sertânia [IPA]-SNG, Miúda [MIU]-SNG, OEM–SF11, OEM–Progenitor 288 [P.288], OEM–467, IPA–SF11, IPA–P.288, IPA–467, MIU–SF11, MIU–P.288 and MIU–467); in the second and third experiments, the cactus–sorghum system was planted under different planting densities (100,000; 50,000; 33,333; 25,000 and 20,000 plants ha⁻¹ for forage cactus and 200,000 plants ha⁻¹ for sorghum) in east–west and north–south orientations, respectively; and the fourth experiment consisted of different planting densities for the cactus and sorghum (50,000; 40,000; 33,333; and 28,571 plants ha⁻¹ and 200,000; 160,000; 133,333; and 114,285 plants ha⁻¹, respectively). The maximum values of the dry matter accumulation rate were observed in the cultivation configurations that contained the OEM clone and at the highest densities. The different cultivation configurations affected the duration and number of phenophases. The cutting time increases as the planting density increases (50,000 and 100,000 plants ha⁻¹) and when the OEM clone is used.