Efficiency Of Groundwater Use Research Articles

Nitrogen Fertilization Effects on Soil Nitrate, Water Use, Growth Attributes and Yield of Winter Wheat under Shallow Groundwater Table Condition

Shallow groundwater plays a vital role in water use and the yield of winter wheat. Nitrogen (N) application significantly affects crop uptake and utilization of water from irrigation, but little is known about groundwater use. More importantly, excessive N application will also bring a series of environmental problems. An experiment was carried out in micro-lysimeters at 0, 150, 240, and 300 kg/ha N fertilization rates based on 0.6 m groundwater depth with relatively strong alkaline soil in the winter wheat growing season. The results showed that increasing the N application rate significantly increased the sensitivity of the daily groundwater evaporation velocity of winter wheat to environmental meteorological factors (soil surface moisture, humidity, atmospheric pressure and atmospheric temperature), and promoted crop water use, crop growth and yield under the 0.6 m groundwater depth. From 150 kg/ha to 300 kg/ha N fertilization, LAI and yield increased by 26.95–82.02%, and evapotranspiration (ET) and groundwater use efficiency (GUE) increased by 11.17–14.38%. However, a high N application rate would sharply induce surface soil drought, leading to a rapid increase in nitrate accumulation in the vadose zone and a significant decrease in partial factor productivity of applied N (PFPN). With the N application of 150–300 kg/ha, the accumulation of nitrate in the vadose zone increased by 8.12 times, and soil moisture in 0–20 cm and PFPN significantly decreased by 19.16–57.53%. N fertilization had a significant effect on water transfer and could promote the consumption and utilization of groundwater at 0.6 m depth. Considering yield, water use, the accumulation of nitrate, and PFPN, the optimal N application was 219.42–289.53 kg/ha at 0.6 m depth.

An economic analysis of groundwater markets and water use efficiency in hard rock area of Hosur union Krishnagiri district of Tamil Nadu

Groundwater selling is a guarantee against deficiency rains in areas where farmers do not have access to surface water irrigation. Therefore, examination of groundwater market development and the efficiency of groundwater use under different water regimes needs to be studied. The objective of the study was (a) to analyse the structure and contact of groundwater markets and (b) to estimate the cost of ground water extraction and selling price in Hosur and Kaveripatinam taluks of Krishnagiri district, Tamil Nadu. Based on the Primary survey, water structures were analysed using simple statistics and measured efficiency by Data Envelopment Analysis. The groundwater market structure demonstrated that the number of irrigation water buyers grows as the size of the farm decreases, while the number of irrigation water sellers grows as the size of the farm increases. The efficiency of groundwater use is estimated by data envelop analysis. According to the data, in a sample of groundwater markets, the seller-buyer concentration ratio was 1:1.13. The cropping intensity and irrigation intensity were highest (89.13 and 93.19 %, respectively) for the self-user+seller category. The selling price of groundwater (Rs. 50 per tank) was marginally higher than the total cost of water extraction (Rs. 28.27 per tank), thereby implying the exploitative nature of groundwater markets. According to findings on input consumption and landholdings, water buyers are resource-strapped farmers who are unlikely to be able to afford the large investments required to install a well.

Assessment of groundwater resources in Siwa Oasis, Western Desert, Egypt

One of the major challenges facing Egypt is limited water resources associated with rapid increase in population. In 1960s, Egyptian government started to use groundwater from the Nubian Sandstone Aquifer System (NSAS) in the Western Desert to expand agricultural sector. Siwa Oasis is the focus of this study to assess the efficiency of groundwater use and corresponding impacts from 1980 to 2012. Results show that from 1980 to 1998, withdrawal from poorly designed wells increased rapidly causing an increase in excess water about 336%. The increase of excess water with the usage of poor drainage produced lakes. Remote Sensing showed in 2000, there were 21,348 acres of lakes with an increase of 89% since 1987 due to unmanaged withdrawal. After management intervention, excess water decreased about 94.7% from 1998 to 2012 causing a decrease in lakes area by 24%. Groundwater electrical conductivity (EC) increased from 4.5 to 10.5 ds/m in 1996 and 2013, respectively. Yields of olives and date palms decreased about 46% and 55%, respectively from 2000 to 2011 resulting in net revenue decrease of more than 60%. Results show that salinity has a strong negative correlation with yield and net revenue. Findings showed the importance of developing a meaningful groundwater resources management plan for Siwa region.

Building a System Dynamics Model to Achieve Optimal Economic Efficiency of Groundwater Use, Case Study: Wadi Al-Dawasir, Saudi Arabia

An agricultural hydro-economic System Dynamics model is built to study optimal solutions for economic efficiency of groundwater use and to achieve water and food sustainability in Wadi Al-Dawasir. Seven scenarios are proposed for the period (2017-2030). These scenarios are designed to study the anticipated effects of the government’s decision to stop growing fodder crops by 2019. The results showed that the implementation of this decision would reduce the cumulative depletion of water by 21 billion m3. In addition, the transfer from fodder to vegetable farming is the least water consuming and offers higher value agricultural products than other scenarios.

Groundwater facilitated water-use efficiency along a gradient of groundwater depth in arid northwestern China

Groundwater strongly impacts ecosystem performance in arid regions by driving vegetation structure and species distribution. It is unknown how water use efficiency varies along a gradient of depth to groundwater (DWT). In this study, we developed a framework to estimate water use efficiency (WUE), groundwater use efficiency (GUE), and rain use efficiency (RUE), and to examine the contribution of rainfall to transpiration in groundwater-dependent ecosystems (GDEs). The method was applied to an arid region in northwest China with a gradient of groundwater depth from 0.5 to 12m. The results indicate that the above-ground primary production, evapotranspiration, plant transpiration, WUE, and GUE decreased significantly from riparian forest, wetland, oasis edge, desert-oasis ecotone, and to sandy desert along a gradient of increasing DWT. RUE is found to be 0.26gm−2mm−1 at the sandy desert without groundwater contribution where 21% of rainfall is used for transpiration. Water use efficiency increases to 0.85gm−2mm−1 at the riparian site where groundwater is about 0.5m depth. The fraction of rainfall consumed by plants increases with a decreasing DWT from a threshold of 6.3m, suggesting groundwater enhances rain use efficiency in GDEs.

Yield production and water-use efficiency of wheat (Triticum aestivum L.) cultivars under shallow groundwater use in semi-arid region

As a free water resource, groundwater is extensively used for agricultural purposes. This is sometimes referred to as underground irrigation. Two-year lysimetric experiments from 2009 to 2011 were conducted in order to determine the effects of different shallow water table levels without any supplementary irrigation on water requirements, yield production and water-use efficiencies of three wheat cultivars namely W33g, Cross Alborz and Bahar. The experiments were carried out in a randomized complete block factorial experiment design with three replicates at the Razi University Lysimetric Research Station, Iran. Nine treatments were applied to each experiment by maintaining groundwater EC of 5 dS m−1, with different water table levels of 0.6, 0.80 and 1.10 m, respectively. The results showed the highest and lowest groundwater uses by wheat for water table depths of 0.6 m and 1.10 m, during the experimental years, respectively. For all wheat cultivars, the average groundwater contributions were found to be 70.90% (5 mm day−1), 67.85% (4.3 mm day−1) and 63.4% (3.6 mm day−1) for water table levels of 0.60, 0.80 and 1.10 m, respectively. Finally, the results showed the highest yield production and groundwater-use efficiency under water table levels of 0.80 m for all the three wheat cultivars.

Estimating the causal effect of water scarcity on the groundwater use efficiency of rice farming in South India

There is no consensus among researchers on the influence of scarcity on common pool resource use: some suggest that scarcity leads to prudent use, whereas others suggest that it will cause over-extraction of resources. This issue is particularly of interest for developing countries, where natural resources are becoming scarce at an alarming rate. This paper investigates the causal association between water scarcity and groundwater use efficiency in a rice based cropping system in south India, where groundwater is increasingly becoming a scarce resource. Contextualization of the work is done under the premise of reported contradictions concerning the scarcity — efficiency nexus. Using a two stage approach the causality is estimated: first, farm level groundwater use efficiency (GWUE) scores are calculated using non-parametric efficiency analysis, and then these inefficiencies are linked to farm level scarcity indicators using the Inverse Probability Weighting method. Our results showed a negative causal association between farm level water scarcity and GWUE, indicating the existence of competitive appropriation behavior in the face of scarcity. Hence, policy measures to conserve groundwater should include supply enhancement to remove the threat of immediate scarcity on farm to avoid inefficient pumping in addition to demand management measures and improved governance.

Groundwater Demand Management in the Great Lakes Basin—Directions for New Policies

Demand-side management should be used to maximize the efficiency of groundwater use. Implementation of conservation measures would decrease the volume of water use and also exert less pressure on the water distribution system as well as the wastewater treatment system. Allocation of ground water in the Great Lakes basin must conform to priorities established at the community level. Groundwater pricing should reflect the full costs arising from ground water use. A differential pricing structure would help conserve water in the residential and industrial sectors. A user-friendly database on ground water use, quality and quantity for the entire Great Lakes basin is also essential. New policies for sustainable groundwater allocation, regulating water prices for water conservation, conservation education, pollution prevention, recycling and reuse of water as well as effective information management provide new directions for managing the groundwater demand in the Great Lakes basin.

An Analysis of Production and Financial Performance of Baitfish Production

Indicators of performance efficiency provide benchmarks for measuring and comparing fish farm performance over time. A set of production and financial performance analysis indicators was developed specifically for commercial baitfish production and was utilized on commercial farms from 1996-1997. Results provide an in-depth and comprehensive financial portrait of baitfish production. This study measured the high degree of variation across baitfish farms in both production practices and in production performance. Yields averaged 370 ±117 kg/ha, 1,697 ±1,584 kg/ha, and 182 ±78 kg/ha for golden shiners (Notemigonus crysoleucas) goldfish (Carassius auratus) and fathead minnows (Pimephales promelas) respectively. On average, 1 ha of brood pond was required for each 13.6 ha of growout ponds. Water use ranged from 2.2 ±3.0 m/ha of water surface area for golden shiners, 0.40 ±0.55 m/ha for goldfish, and 0.72 ±0.72 m/ha for fathead minnows. Labor represented the greatest single cost item in baitfish production, and its efficiency ranged from 5.0 ±1.2 kg of fathead minnows per hour of labor to 26.9 ±35.5 kg of goldfish per hour of labor. Total operating cost per kg of fish produced was $2.64 ±1.21, $1.25 ±0.66, and $6.5 ±5.1 for golden shiners, goldfish, and fathead minnows. These indicators can be used to compare farm efficiencies from one year to the next and allow baitfish farmers to measure and evaluate the farm-level impacts of new spawning, hatching, and production technologies. Measured indicators of pond productivity, efficiency of ground water use, and labor and economic efficiency are expected to show significant improvement as new spawning, hatching, and pond management technologies become more widely adopted.