Rainwater Harvesting Techniques Research Articles

Water conflict analysis in the Balangan Irrigation Area: causes, impacts, and management strategies

The Balangan irrigation area has grappled with a 20-year water shortage due to disorganized canal systems, causing water scarcity in droughts and floods during the rainy season. Conflicts between upstream and downstream users compound these challenges. This study analyzes water conflicts, their causes, impacts, and resolution strategies. Employing descriptive approaches, it identifies factors triggering conflicts, their societal and agricultural effects, and sustainable solutions. Findings reveal that the narrowing of water channels, exacerbated by concrete structures, has caused an imbalance in water distribution between Subak Balangan and Subak Palean. Sedimentation and irregular channel regulation exacerbate water loss and prolonged scarcity. The study underscores the necessity of comprehensive management strategies, prioritizing Water Rights and Allocation Policies, Community Participation, and Rainwater Harvesting and Conservation. These strategies promise practical, feasible, sustainable, and impactful solutions. Regulating water rights and allocations provides a framework, and community engagement ensures local perspectives are considered, while rainwater harvesting and conservation techniques reduce water stress and foster agricultural resilience. Integrating these strategies can achieve a comprehensive approach to sustainable water management in the Balangan Irrigation area.

Optimizing the planting time and stand density of sunn hemp intercropping for biomass productivity and competitiveness in a maize-based system

ContextOptimizing cover crop intercropping should aim to be sustainable, economically feasible and environmentally benign. Significant consideration must be given to cover crop plant timing and stand density adjustments to complement the resource demands of the dominant crop, while ensuring optimal biomass yields. ObjectiveThe study assessed a range of intercropping indices to evaluate the influence of different planting times and stand densities of sunn hemp (Crotalaria juncea L.) when intercropped with maize (Zea mays L.). The evaluation focused on interspecies interactions in relation to aboveground biomass production. MethodsA split-plot experiment was conducted using the in-field rainwater harvesting (IRWH) technique. The main plot factors included three intercropping times: simultaneous with maize planting, at the V15 and the R1 maize growth stages. The subplot factors consisted of three stand densities (16, 32 and 48 plants m−2), with three replicates for both the 2019/20 and 2020/21 seasons. Intercropping indices, including land equivalent ratio and coefficient, area time equivalent ratio, land use efficiency, system productivity index, percentage yield difference, relative crowding coefficient, aggressivity, competitive ratio and actual yield loss were employed to assess interspecific interactions and their impact on biomass productivity. ResultsResults show that intercropping sunn hemp at maize planting or the V15 maize growth stage can reduce stand density to 32 plants m−2 without reducing sunn hemp biomass yield. The land equivalent ratio was highest (2.20), with intercropping at the V15 maize growth stage and lowest (2.09) with simultaneous intercropping at maize planting. The relative crowding coefficient was highest (34.4) at the V15 maize growth stage at 32 plants m−2 stand density and lowest (−45.9) with simultaneous intercropping at planting at the same stand density. Intercropping during the R1 maize growth stage influenced competition on sunn hemp with the highest actual yield loss of − 0.07. Competitive ratios were significantly higher for maize (26.19) and sunn hemp (0.16) with R1 and V15 maize growth stage intercropping, respectively. However, sunn hemp's actual yield loss was higher (0.25) with intercropping during the V15 maize growth stage than in sole cropping. ConclusionsIntercropping sunn hemp both simultaneously with maize planting and during the V15 maize growth stage with a stand density of 32 plants m−2 demonstrated enhanced biomass productivity, thereby offering viable intensification choices. The utilization of multiple intercropping indices can contribute to a more comprehensive and precise evaluation of interspecies interactions, consequently leading to improved decision-making.

Planting time and stand density effect on radiation interception and use efficiency of maize and sunn hemp intercropping in semi-arid South Africa

Solar radiation must be efficiently utilised to enhance dry matter accumulation and carbon sequestration capacity within dryland agroecosystems. The study evaluated the effects of sunn hemp (Crotalaria juncea L.) intercropping time and stand density on radiation interception and radiation use efficiency (RUE) in a maize-based system. Field experiments were conducted under the in-field rainwater harvesting (IRWH) technique for two consecutive growing seasons, 2019/20 and 2020/21. Radiation interception and productivity were measured and calculated for maize and sunn hemp, sole and intercrops. The intercrops were identified by the sunn hemp intercropping times [simultaneous with maize planting (P1), at V15 maize growth stage (P2), at R1 maize growth stage (P3)] and stand densities [16 plants m–2 (D1-low), 32 plants m–2 (D2-medium), 48 plants m–2 (D3-high)]. Total radiation interception was calculated using a row-crop radiation transmission (RCRT) model from strip width of component crops, extinction coefficient (k), plant height, and leaf area index (LAI) measurements taken throughout the growing season. The results showed that the LAI of sunn hemp was high when intercrop was planted simultaneous with maize planting and at 48 plants m–2. The overall k for the sole sunn hemp (SSH) cropping system was 0.37. The correlations (r2) between the modelled and measured fractions of photosynthetic active radiation (PAR) in simultaneous maize planting, V15 maize growth stage, and R1 maize growth stage intercropping treatments were 0.87, 0.97 and 0.93, respectively. Simultaneous planting of sunn hemp intercrop with maize captured the most growing season PAR of 798.70 MJ m–2 and had the highest RUE of 1.42 g MJ−1. These results suggest that intercropped sunn hemp planted simultaneously with maize would help to increase production through the more efficient use of solar radiation. Optimising planting time and density can help plan the planting time to increase radiation utilisation in maize/sunn hemp intercropping systems.

In-Field Rainwater Harvesting Tillage in Semi-Arid Ecosystems: II Maize-Bean Intercrop Water and Radiation Use Efficiency.

The purpose of this study was to evaluate alternative management practices such as in-field rainwater harvesting (IRWH) and intercropping techniques through conducting on-farm demonstrations. Seven homestead gardens in Thaba Nchu rural communities in the central part of South Africa were selected as demonstration trials. Two tillage systems, conventional (CON) and IRWH, as the main plot, and three cropping systems as sub-plot (sole maize and beans and intercropping) were used to measure water use and radiation use parameters. The water productivity (WP) of various treatments was positively related to the radiation use efficiency (RUE), and the degree of associations varied for different tillage systems. The water use in IRWH was higher by 15.1%, 8.3%, and 10.1% over the CON for sole maize and beans and intercropping, respectively. Similarly, the intercropping system showed water use advantages over the solely growing crops by 5% and 8% for maize and by 16% and 12% for beans under IRWH and CON tillage, respectively. Maximum RUE was found for sole maize and beans under IRWH, higher by 13% and 55% compared to the CON tillage, respectively. The RUE under IRWH tillage was estimated to be 0.65 and 0.39 g DM MJ-1 in sole maize and intercropping, respectively. However, in sole and intercropped beans, the RUE showed higher values of 1.02 g DM MJ-1 and 0.73 g DM MJ-1, respectively. WP and RUE were associated with water deficits and proportional to lower radiation use. This relationship indicates that the intercepted radiation by plants for photosynthesis is directly related to the transpiration rate until radiation saturation occurs. Therefore, the higher water deficit and lesser efficiency in using the radiation available during the season can be improved by practicing IRWH techniques. Furthermore, in semi-arid areas, to enhance the efficiency of water and radiation usage in intercropping management, it is crucial to adjust plant population and sowing dates based on water availability and the onset of rainfall.

Urban Floods and Suitability Analysis of Rainwater Harvesting Potential Areas in Lahore City, Pakistan

There is a growing threat of urban flooding, particularly in Pakistan that needs attention and requires effective management strategies. The chief trigger for urban flooding is the rapid and unplanned urbanization in areas where impermeable surface inhibits rainwater diffusion and changes the natural water flow. In many developed countries, a technique of rainwater harvesting is implemented as a sustainable strategy to manage urban stormwater. Most studies and projects chiefly focused on the potential use of the Rainwater harvesting technique for water conservation in arid and semi-arid climates. In the present work, GIS and remote sensing methodologies are utilized for the suitability of rainwater harvesting structures. This study was conducted in Lahore, the second most populated city of Pakistan and the capital of Punjab. Generally, the water harvesting technique depends on topographical areas with water accumulation, where there is an availability of open spaces in the form of green areas and barren lands, rainfall, drainage network density, and rainfall distribution, particularly in the urban environment. The SRTM DEM data were used for finding high water accumulated areas, and the Landsat OLI image is used to retrieve land use information i.e. vacant land and open green spaces, existing drainage network density, and rainfall distribution. All these layers were integrated through AHP to detect the potentially suitable sites for the construction of rainwater harvesting structures. Results concluded 94 suitable sites with categorization from highly to critically suitable for the construction of rainwater harvesting structures in which 6 were highly suitable areas in Data Gunj Bakhsh Town and Ravi Town. Besides, residential areas are having a maximum site suitability percentage, followed by roads, agricultural and open spaces in the area under consideration. Considering the suitable sites, further rainwater harvesting methods can be identified in the study area to alleviate urban flooding and improve the urban environment.

Pemanfaatan Teknik Rainwater Harvesting sebagai Pemenuhan Kebutuhan Air Domestik di Desa Cot Mee

The use of artesian wells or drilled wells is still the main choice of the people of Cot Mee Village, one of the areas in Nagan Raya Regency, where this is done to meet the needs of raw water sources as domestic needs. In addition to the expensive cost of installing borewells, this also adversely affects the environment due to excessive use of groundwater and raises the potensial for land subsidence. Under these circumstances, in order to solve the problem of raw water for individual lives, alternative solutions are needed that are more effective and efficient. One of alternative is to create a rainwater harvesting system from the roof of the building by maximizing high rainfall or known as rainwater harvesting technique. Field studies show the building area in Cot Mee Village is currently in good condition and livable and the entire roof is made of zinc. Of course, this condition will be very maximum in the process of harvesting rainwater. Analysis of the potensial for rain harvesting in Cot Mee Village is 64,685.61 liters/day, with the potential for rainwater harvesting per house of 743,512 liters/day. The ratio between the total water harvested amounted to 64,685.61 liters/day with the total use of raw water for needs of the people of Cot Mee Village of 43,399.8 liters/day. Research shows that rainwater harvesting technique will be adequate and able to be an alternative in providing raw water for domestic needs.

Scaling Up Indigenous Rainwater Harvesting: A Preliminary Assessment in Rajasthan, India

Rainwater harvesting (RWH) has the potential to enhance the sustainability of ground and surface water to meet increasing water demands and constrained supplies, even under a changing climate. Since arid and semi-arid regions frequently experience highly variable spatiotemporal rainfall patterns, rural communities have developed indigenous RWH techniques to capture and store rainwater for multiple uses. However, selecting appropriate sites for RWH, especially across large regions, remains challenging since the data required to evaluate suitability using critical criteria are often lacking. This study aimed to identify the essential criteria and develop a methodology to select potential RWH sites in Rajasthan (India). We combined GIS modeling (multicriteria decision analysis) with applied remote sensing techniques as it has the potential to assess land suitability for RWH. As assessment criteria, spatial datasets relating to land use/cover, rainfall, slope, soil texture, NDVI, and drainage density were considered. Later, weights were assigned to each criterion based on their relative importance to the RWH system, evidence from published literature, local expert advice, and field visits. GIS analyses were used to create RWH suitability maps (high, moderate, and unsuited maps). The sensitivity analysis was also carried out for identified weights to check the inadequacy and inconsistency among preferences. It was estimated that 3.6%, 8.2%, and 27.3% of the study area were highly, moderately, and unsuitable, respectively, for Chauka implementation. Further, sensitivity analysis results show that LULC is highly sensitive and NDVI is the least sensitive parameter in the selected study region, which suggests that changing the weight of these parameters is more likely to decide the outcome. Overall, this study shows the applicability of the GIS-based MCDA approach for up-scaling the traditional RWH systems and its suitability in other regions with similar field conditions, where RWH offers the potential to increase water resource availability and reliability to support rural communities and livelihoods.

Contribution of homestead food garden towards food availability in Tshwane Metropolitan Municipality - Region 7, Gauteng Province of South Africa

The government of South Africa has a political and economic incentive to guarantee that people have access to enough nutritious food to always meet their needs, but many households in the nation still struggle to attain food security. Among its various initiatives, the South African government has introduced a Homestead Food Garden (HFG) program that aims to increase food production to combat hunger, malnutrition, and food insecurity. Even though the struggle to achieve food security at household level in peri-urban areas of Gauteng Province dates back a long period, it has remained as a challenge goal even today. The study's objective was to determine how much HFG contributes to the availability of food in households in region 7 in the City of Tshwane and the factors that influence this availability using the Ordered Logistic Regression (ORD) model. A total of eleven explanatory variables were included in the pragmatic model. To ensure a representative sample size, 258 individuals were chosen at random from the study's survey design, which was quantitative in nature. Face-to-face interviews were conducted to gather data using a semi-structured questionnaire. The results showed that 83% of the participants continued to cultivate their homestead gardens after receiving support from HFG program; thus, the program improved food availability in the households of the gardeners. Food availability was positively and significantly influenced by age, other support program received, and the availability of homestead gardens (p<0.01). From seasonal perspectives, there were more food available from domestic gardens in the summer than in the winter. In addition, more food was available in spring season gardens than in summer and winter. The type of food crops cultivated by majority (65%) of the participants was spinach. As such, HFG program improved household food availability mostly during spring and summer. Therefore, it is advised that policymakers should encourage targeted communities and youth to utilize vacant space in their backyards for food gardening. As part of HFG program, government should provide training about rainwater harvesting techniques to enable gardeners to conserve water for sustainable production throughout the year. Key words: Homestead Food Garden, Food availability, Food security, Households, Gauteng Province

Multi-criteria decision support system for selecting the rainwater harvesting technique in wadi systems, Sinai, Egypt

Abstract Recently, some areas are exposed to water scarcity and floods, and rainwater harvesting (RWH) is a practical solution, particularly in arid and semi-arid regions. The Wadi Watier basin located in South Sinai, Egypt was selected to identify the appropriate RWH techniques. Five alternatives were proposed: a dam with a reservoir, a storage pond, an underground tank, wadi bed cultivation, or a Jessor system. The hydrological model was built using the WMS software to determine the runoff volume at the proposed RWH sites. Multiple criteria were identified and classified based on their suitability degree. Then, an analytic hierarchy process (AHP) was used to assign the effective weight of each evaluation criterion. The AHP revealed that the wadi slope and initial cost have the highest evaluation influence of 20%, followed by the wadi width of 15%. The rainfall volume, social acceptance, and cost revenue have moderate influences with weights from 8 to 11%. Finally, the storage ponds and underground tanks recorded the highest-suitability evaluations at the selected RWH sites, at 65.4 and 62.7%, respectively. The dam with a reservoir recorded 49.3%, which is considered medium suitability, while wadi bed cultivation and Jessor systems were classified as low-suitability evaluations with 42.7 and 41.7%, respectively.

Risk Mitigation Practices in Urban Gardening: A Case of Small Minority Producers in Maryland

Urban gardening (UG) serves to increase the production and consumption of fresh produce in urban and semi-urban areas. A project was implemented in 2022 to enhance the technical, allocative, and economic efficiency of small, socially disadvantaged minority farmers engaged in UG. Data were collected from 22 of the project’s participating producers. The findings revealed that farmers operated rationally, and cultivated diversified specialty and ethnic crops and medicinal herbs, with an average of 20 crops on 1.2 acres. As rational producers, based on data-driven evidence, farmers practiced integrated alley and mixed cropping systems (crops such as leafy, root, climbers, cash, herbs, and fruits), adopted a rainwater harvesting technique, expanded compost-making, maintained high cropping diversity, and introduced a tier system of production to mitigate production, marketing, and financial risks. Besides the socio-economic and health benefits, an increase in the production of vegetables locally will eventually help to lower the carbon footprint.

Rain Water Harvesting Technique Implementation for the Chhadvel Korde Village, Maharashtra

Water is one of the most important resources on Earth. In every way, water is crucial to our daily existence. The amount of water that is available in cities is never enough to meet the entire demand. We must rely on water from underground sources because surface water is not readily available. The amount of rainwater that soaks into the subsurface and replenishes ground water has significantly decreased as a result of rapid urbanisation. In this instance, there must be additional supply to satisfy the demand. When it rains, pure rainwater can be gathered "wherever it falls" to instantly replace the water supply. The act of gathering and organising rainwater in a systematic way for later use is referred to as "rainwater harvesting". Two types of rainwater harvesting that could be used in the research region are rooftop and surface runoff harvesting. By adopting a rainwater harvesting system and constructing natural percolation pits, the groundwater level, soil moisture, and soil fertility can all be increased for plantations. Therefore, using this simple strategy typically leads to more vegetation, which raises the aesthetic value. This article examines every rainwater harvesting system established in the Maharashtra district of Sakri in Chhadvel Korde.

Design of Water Source Alternative Based on SWAT Model Simulation

Water shortage problem was often happened in many places in Indonesia. Water availability is very important not only for domestic needs, but also for other activities particularly for agricultural activities. To solve water shortage problem, this study aimed to design a water source alternative. The rain is a free water source and collecting rain in the small dam or reservoir is one of the effective rainwater harvesting technique that can increase water availability. This research was conducted at Sekaran Village and the analysis had done using SWAT (Soil and Water Assessment Tools) model. The planned rainfall and discharge were analysed by 5 years return period to calculate the water potential for reservoir charging. The results of this study indicated that the location of the reservoir was planned in a forest area with a slope of 8-25%, on coordinates 111º38'11.39"E and 7º6'14.22"S and has a storage volume of 13737 m3. The reservoir has 4356 m2 surface area with a depth of 3 m. Based on the SWAT model simulation, the highest average discharge potential occured in February with a discharge of 0.312 m3/s and the lowest average discharge occured in October with a discharge of 0.044 m3/s. The total volume of potential annual water that can fill the reservoir is 61.166 m3/s per year based on a planned rainfall of 115.38 mm and a planned flood discharge of 2.54 m3/s with a return period of 5 years. The reservoir construction required a cost of IDR 1,200,747,000. Keywords: Cost, Location, Rainwater Harvesting, Reservoir, SWAT

Enhancing Sorghum bicolor (L.) grain yield with the use of field edge rainwater harvesting and NPK fertiliser in a dry region of Zimbabwe

AbstractBackgroundFarmers in marginalised areas across Africa are mainly resource poor and have limited capacity to procure enough inorganic fertilisers. This contributed immensely towards declining crop productivity causing food insecurity. Soil moisture stress is another key factor which has led to a decline in crop yields across semi‐arid areas. This experiment determines the effects of field edge rainwater harvesting and NPK fertiliser microdosing on sorghum grain yields and agronomic nutrient use efficiency of two sorghum varieties (Macia and SV1). Rainwater harvesting techniques was the main plot factor with three levels (tied contour, infiltration pits and standard contour), sorghum variety was used as subplot factor with two levels (Macia and SV1) and NPK fertiliser as sub‐sub plot factor with five levels (0, 25, 50, 100 and 150 kg ha−1) with all treatments replicated three times. A randomised complete block design arranged in split‐plot was used.ResultsPhosphorous was significantly increased from 3.32 to 3.52 mg kg−1 with no significant (p > 0.05) increase in total nitrogen and soil organic carbon. Sorghum grain yields were statistically (p < 0.05) influenced by main treatment factors. Tied contour had considerably higher grain yield (861 kg ha−1) than infiltration pits and standard contours. Highest grain yield of 909 kg ha−1 was observed from plots applied 150 kg ha−1 NPK fertiliser. Macia variety performed significantly (p < 0.05) higher than SV1. Grain yields show significant (p < 0.05) increase with increasing fertiliser levels. Interaction of tied contour + Macia+ 150 kg ha−1 NPK fertiliser had significant grain yields (1150 kg ha−1) compared to other treatments. Treatments applied NPK fertiliser show significant differences (p < 0.05) than unfertilised plots. Agronomic nutrient use efficiencies were significantly higher (p < 0.05) from all treatments applied 25 kg ha−1 NPK fertiliser. Sorghum variety Macia had better nutrient use efficiency than SV1 in 2017/18 and 2018/19 seasons except during 2019/20 where results show insignificant differences.ConclusionIt can be concluded that farmers adopt the use of tied contour and Macia variety using 150 kg ha−1 to achieved higher yields. Combining rainwater harvesting method of tied contour and mineral fertiliser can increase sorghum grain yields in dry regions.

Evaluation of different rainwater harvesting techniques for improved maize productivity in semi‐arid regions of Zimbabwe with sandy soils

AbstractBackgroundMaize production in semi‐arid areas has been hindered by moisture stress and poor soil fertility. Long frequent droughts and shortening of growing seasons have been causing yield reduction. Limited knowledge of soil water management by farmers is another key contributor to poor maize yields in the smallholder sector. Therefore, the objective of the study was to investigate the effects of contour‐based and field‐based water harvesting technologies on maize grain yield and rainwater use efficiency under rain‐fed conditions on three farms (Jera, Kudzeeta and Manjengwa) with sandy soils in the Marange smallholder farming area of Zimbabwe. The experiment was laid out as a split plot in a randomised complete block design with three replications at each site. Contour‐based rainwater harvesting structures were the main treatments comprising tied contour (TC), standard contour (STDC) and infiltration pits (IP). Field‐based rainwater harvesting structures were the subplot treatments comprising tied ridges (TR), pot holing (PH) and the flat system (FLAT).ResultsResults showed that the contour‐based water harvesting structures significantly influenced (p < 0.05) maize grain yields. TCs had the highest maize grain yields compared with infiltration pits and STDCs over two cropping seasons. Maize yields on field‐based TR were significantly higher (p < 0.05) than on the FLAT but were not different (p > 0.05) with what was obtained on PH. The combination of TC and TR water harvesting technologies resulted in significantly higher maize yields (p < 0.05) than other combinations. TR and STDC also gave higher maize grain yield at Jera farm which was significantly different from other two farms. Rainwater use efficiency followed the same trend as maize grain yields, with TC having higher values but not significantly different (p > 0.05) from STDC.ConclusionIt can be concluded that farmers in semi‐arid areas adopt a combination of TC with either TR or PH to improve rainwater use efficiency and maize yields.

Socio-economic status for qualitative and quantitative assessment towards crop diversification and sustainable agriculture under different components Punjab

The study is based mainly on primary data collected through socio-economic survey schedule from nearby villages of Kharar town falling under Municipal Corporation of Sahibzada Ajit Singh Nagar (Mohali) Punjab. Different components of socio-economic survey include socio-economic status soil agronomic practices cropping status and soil sampling to achieve the target of qualitative and quantitative data for Crop diversification, economic status and socio-economy of farmers from Punjab. There were various parameters related to cropping pattern, livestock production and other suitable parameters related to Agriculture farming for the livelihood status and economic viability. The study was conducted under Rural Agricultural Work Experience programme by the students of Agriculture from University Institute of Agriculture Sciences, Chandigarh University Gharuan (Mohali) Punjab. In this study more than two hundred farmers were involved with proper questionnaire and thorough interaction of students. Questionnaire contains the information about the Socio-economic profile, Crop diversity and economic viability of farmers. Socio-economic profile includes the farmer’s family composition, academic qualifications, caste system, income per-cent, and land holding capacity and other important information, social participation, source of information about agricultural information, extension activities. Proper surveys were conducted in which the interaction was done with the farmers at their houses in the form of interview from the survey conducted it is concluded that the literacy rate of the different villages is about ninety per cent. Nearly forty five per cent (45%) of the village farmers are medium farmers and 30% of the farmer’s marginal farmers and other farmers have leased the land for farming. About 90% were present on social media platforms and 10% are not present on social media. Besides that main focus was to identifying problem of the area and their solution. Therefore to sustain agriculture and solve some of the visible problems different campaigns rallies and farmers awareness cum training program were organised by our students in collaboration with Krishi Vigyan Kendra, Kurali (GADVASU, Ludhiana) and department of agriculture Punjab by presenting different models various extension activities and providing nourishment at University level. The farmers were addressed for their major crop issues and were made aware about various innovative ideas promoted by Students, KVKs, rural societies and other NGOs. Majority of the farmers are lacking knowledge about latest technologies, rain water harvesting techniques and application of bio-control. Adequate policies prioritization of agricultural components and utmost utilization of resources are prime need.

The Effect of Agronomic Management on Micronutrients of Vegetables Grown by Smallholders in Free State and KwaZulu-Natal Provinces of South Africa

The production of nutritious food amongst rural farmers has been a challenge for m Cany years. Challenges can be attributed to many factors, including poor access to water, use of old planting methods, financial challenges, etc. Therefore, new climate-smart technologies (CSTs) were introduced to the farmers. The CSTs implemented in the study were in-field rainwater harvesting (IRWH) techniques compared with conventional production (CON). These technologies were applied in combination with sound agronomic management practices, such as mulching and fertilizer application, to produce cabbage, beetroot, spinach and orange-fleshed sweet potato. The vegetables produced were harvested and their nutritional composition analysed to assess whether or not agronomic treatments, water-use technology and season affected their micronutrient levels, with a particular focus on provitamin A and mineral levels. The main finding of the study was that the nutrient levels of the vegetables can be enhanced by adopting IRWH technology combined with different agronomic treatments, especially including mulching as one of the treatment combinations. Limitations: Farmer research participants did not always adhere to research agreements, particularly regarding reserving vegetable samples for analyses. As a result, some experiment replicates are missing. Value: The study findings are of socio-economic significance as they demonstrate that rural, small-scale farmers can apply local, accessible and appropriate agronomic treatments and water-use technologies to achieve economically viable yields of nutritive vegetables to enhance food and nutrition security and household livelihoods of the farmers.

Estimating soil water evaporation as influenced by “dry-and green-mulch” cover beneath maize canopy

Soil evaporation reduction can improve rainfed crop production in semi-arid climates. The purpose of this study was to develop empirical models to estimate cumulative soil evaporation (∑Es) from a maize field across the basin and runoff area (BA and RA) of the in-field rainwater harvesting (IRWH) technique as influenced by different levels of stover mulch ("dry-mulch") and canopy shading ("green-mulch"). Soil water evaporation (Es) was measured with micro-lysimeters 300 mm deep and 71 mm in diameter in the BA and RA sections for three consecutive drying cycles. Four different runoff strip lengths, RSL (RSL-1, 1.5, 2 and 3m) and three mulching levels (ML) of bare, 39%, and 96% were used to estimate the Es. The coefficient crop cover (Kcover) values for full and partial canopy shade (FC and PC) on the RA were in the range of 0.46–0.97 and 0.43–0.94, respectively, while in the BA the Kcover values ranged between 0.33 and 0.92. Under IRWH, the ∑Es values from a basin area beneath a maize canopy averaged 42% of the seasonal rainfall. ∑Es proportion of seasonal rainfall is about 62, 64, and 66 percent for bare soil, but as low as 28, 30 and 32 percent for FC, PC, and unshaded canopy (UC), respectively. In conclusion, the microclimate of the cropping system changes according to surface treatments, which greatly affect the Es losses for the IRWH technique and contributes to ET partitioning. Hence, reducing unproductive water losses in dryland crop production improves water use efficiency by storing more water in the root zone for transpiration.

Effects of intercropping sunn hemp into maize at different times and densities on productivity under rainwater harvesting technique

Maize is a major food crop in Sub-Saharan Africa (SSA), and its productivity is affected by climate change-adaptive sustainable management practices. A 2-year field study (2019/20 and 2020/21 growing seasons) was carried out to evaluate the effect of sunn hemp (Crotalaria junceaL.) living mulch management on maize (Zea maysL.) production. Three sunn hemp planting periods were simultaneous with maize planting (P1), V15 maize growth stage (P2), and R1 maize growth stage (P3) and three densities 16.1 plants m−2(D1-low), 32.1 plants m−2(D2-medium), and 48.1 plants m−2(D3-high). The intercrop components were planted in a split-plot treatment arrangement as an additive series with three replications and laid out in a randomized complete block design under the in-field rainwater harvesting (IRWH) technique. The growing season conditions revealed significant differences in rainfall distribution. Therefore, the planting period had highly significant (p< 0.001) effects on sunn hemp biomass, with an LSD value of 610.2 kg ha−1, showing that the highest was obtained in P2 (2636.7 kg ha−1) compared to P3 (811.3 kg ha−1). However, the P3 treatment resulted in maize grain yield penalty, with yields as follows: P3 (2775.2 kg ha−1), sole maize (3263.8 kg ha−1), P2 (3281.9 kg ha−1), and P1 (3287.8 kg ha−1). P2 yielded a significantly (p< 0.05) high-income equivalent ratio of 2.09, indicating a 109% advantage for increasing farmers' income by integrating sunn hemp under the no-till area of IRWH. P1 and P2 sunn hemp planting periods are viable options for smallholder farmers in summer rainfall regions to improve economic benefits.

Design and investigation on rain saucer: The technique of roofless rainwater harvesting

In many developing countries the most common problem encountered by them is the scarcity of water. The solution to avoid crisis is rainwater harvesting. Rainwater harvesting is a technique in which the rainwater is directly collected into a system during yielding rain periods. As the rainwater harvesting technique is mainly concerned with roofs and we harvest rainwater with different techniques, but through those techniques, we can’t use that water directly for drinking or good purpose without a major Hassel less filtration process. This paper describes the design and investigation on a rain saucer which is a roofless rainwater harvesting technique comprised of different components such as Rain Saucer, simple and mesh filter integrated with the main system. The technique is very useful for catching the rainwater directly without any contact with impurities and it is highly user convenient to store the collected rainwater as per user need. The paper describes the technique that allows us to directly use the harvested water for drinking and any good/domestic purpose without any major filtration processes. And the major benefit is, it is a roofless technique, so we can catch the rainwater anywhere regardless of the roof. Normally the rainwater harvesting techniques don’t contain the purification concept integrated, but we have provided an integrated purification in the project. The technique proved that it is very economical and portable as the system is made up of material that is available at a cheaper cost. Also, the technique is found to be very efficient in collecting rainwater directly without contact with any contamination and regardless of roof.

Assessing Suitable Techniques for Rainwater Harvesting Using Analytical Hierarchy Process (AHP) Methods and GIS Techniques

The objective of this study is to produce suitability maps for potential rainwater harvesting techniques (RWHT) in the West Bank (WB), Palestine. These techniques aim to reduce water scarcity, which is a major problem for the conservation of water resources in the area. Based on literature reviews and expert recommendations, seven RWHts were selected (runoff basin system, contour ridges, cisterns, eyebrow terrace, check dam, on-farm pond, and bench terraces). Analysis methods performed in the Arc GIS environment include spatial analysis and data reclassification. Other calculations include multi-criteria analysis for assigning suitability. Five criteria (rainfall, runoff, land use, slope, and soil texture) for RWHt were analyzed to produce a suitability map for each technique. The results show that runoff basin systems in the northeast and southwest of WB are the most suitable, with about 50% of the area of WB moderately suitable for this technique, while 70% of the area of WB is very suitable for the contour ridge technique. Furthermore, this analysis shows that almost 50% of the WB is very suitable for cisterns. Sixty percent of the area is very suitable for on-farm puddling, especially in the north and southwest of WB. The areas with high suitability for the different techniques comprehensively cover the WB, as shown in the RWHt suitability maps and the integrated map. Nevertheless, this approach can help decision makers in making an initial selection of RWH techniques suitable for their region.