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Capturing spatial variability of factors affecting the water allocation plans—a geo-informatics approach for large irrigation schemes
2022
Waqas, M. M. | Waseem, M. | Ali, S. | Hopman, J. W. | Awan, Usman Khalid | Shah, S. H. H. | Shah, A. N.
Capturing spatial variability of factors affecting the water allocation plans—a geo-informatics approach for large irrigation schemes
2022
Waqas, M. M. | Waseem, M. | Ali, S. | Hopman, J. W. | Awan, Usman Khalid | Shah, S. H. H. | Shah, A. N.
The livelihoods of poor people living in rural areas of Indus Basin Irrigation System (IBIS) of Pakistan depend largely on irrigated agriculture. Water duties in IBIS are mainly calculated based on crop-specific evapotranspiration. Recent studies show that ignoring the spatial variability of factors affecting the crop water requirements can affect the crop production. The objective of the current study is thus to identify the factors which can affect the water duties in IBIS, map these factors by GIS, and then develop the irrigation response units (IRUs), an area representing the unique combinations of factors affecting the gross irrigation requirements (GIR). The Lower Chenab Canal (LCC) irrigation scheme, the largest irrigation scheme of the IBIS, is selected as a case. Groundwater quality, groundwater levels, soil salinity, soil texture, and crop types are identified as the main factors for IRUs. GIS along with gamma design software GS + was used to delineate the IRUs in the large irrigation scheme. This resulted in a total of 84 IRUs in the large irrigation scheme based on similar biophysical factors. This study provided the empathy of suitable tactics to increase water management and productivity in LCC. It will be conceivable to investigate a whole irrigation canal command in parts (considering the field-level variations) and to give definite tactics for management.
Mostrar más [+] Menos [-]Occurrence and spatial variation of antibiotic resistance genes (ARGs) in the Hetao Irrigation District, China
2019
Shi, Wei | Zhang, Hong | Li, Junjian | Liu, Yong | Shi, Rui | Du, Hongyu | Chen, Jianwen
The prevalence and proliferation of antibiotic resistance genes (ARGs) has been identified as an emerging contaminant of concern and a crucial threat to public health worldwide. To determine the occurrence and distribution of ARGs in artificial agricultural irrigation systems, we designed eight sample sites of farmland drainage in the Hetao Irrigation District, Inner Mongolia, China. Results indicated that the distribution of ARGs in sub-drainage canals is influenced by the local urban area, agriculture, and animal husbandry structure. The blaTEM gene was predominant in the water samples (up to 8.98 ARG copies/16S rRNA genes). The average ARG abundance in drainage channel sampling sites was significantly higher than the influent water from the Yellow River, which means that the artificial agricultural irrigation system enhances the abundance of resistance genes in the study area. Moreover, the effluent water of the whole irrigation system presented a lower abundance of ARGs than the influent water. This demonstrates that the Wuliangsuhai watershed ecosystem plays an important role in regulating the abundance of ARGs in the area. In our study, the mobile gene elements correlated with trB, emrD, mexF, and vanC (P < 0.001) in the irrigation system. Additionally, different correlations exist between other special subtypes of ARGs. These findings provided deeper insights into mitigating the propagation of ARGs and the associated risks to public health.
Mostrar más [+] Menos [-]A simulation study of techno-economics and resilience of the solar PV irrigation system against grid outages
2022
Chowdhury, Hemal | Chowdhury, Tamal | Rahman, Md Salman | Masrur, Hasan | Senjyu, Tomonobu
Water is the most fundamental need for better yield in agriculture. Worldwide, diesel and electricity are typically used to pump water which contributes to atmospheric pollution. Besides, a power outage affects the irrigation process badly. Without water, the crop may wither away, causing a substantial economic loss. This paper discusses the resilience of a solar PV system during a power outage. HOMER Pro software was used to perform the techno-economic analysis of solar-based irrigation for four major divisions of Bangladesh, while 1-hour power outage was assigned in REopt lite to model the survivability of the system against the grid outage. The simulation outcomes showed that the energy cost is $0.1496/kWh, $0.1502/kWh, $0.1557/kWh, and $0.1576/kWh for Rajshahi, Sylhet, Dhaka, and Chattogram, respectively. About 45% of excess electricity can be stored after fulfilling all requirements. The system is more economical than a microgrid-based water pumping system and a diesel-based system, and the photovoltaic system is technically and economically suitable to pump water if the nearest grid connection is impossible. When connected to the main utility grid, the system can survive without grid power for several hours, subject to daytime outages.
Mostrar más [+] Menos [-]A Novel Method for Combined Biowaste Stabilization and Production of Nitrate-Rich Liquid Fertilizer for Use in Organic Horticulture
2012
Gross, Amit | Guy, Ofer | Posmanik, Roy | Fine, Pinchas | Nejidat, Ali
A novel system for organic waste stabilization and reuse, combined with production of nitrate-rich liquid fertilizer was developed by manure digestion followed by volatilization of ammonia-rich gas (originating in manure extract) and its nitrification and recovery. This approach has several advantages, including biowaste stabilization and high recovery (over 60%) of manure N mainly as nitrate which is a better N form for many plants as compared to ammonium as the sole fertilizer N. Moreover, the potential utilization of different wastes as N sources in organic horticulture is possible as well as removal of suspended particles and microorganisms (including pathogens) that might otherwise clog the irrigation system and pose health risks, respectively. In a pilot-scale study, the system yielded several hundred liters of nitrate-rich (ca. 11 g N L−1) liquid fertilizer using guano as substrate. In a fertilization experiment, lettuce fertigated with the nitrate-rich extract exhibited better growth and quality compared to the common organic practice of fertigation with guano extract. The resulting stabilized biowaste was estimated as “low-risk” according to current guidelines and may be used for liming or land application.
Mostrar más [+] Menos [-]Evolution and the drivers of water use efficiency in the water-deficient regions: a case study on Ω-shaped Region along the Yellow River, China
2022
Liu, Gang | Najmuddin, Omaid | Zhang, Fan
Enhancement of water use efficiency (WUE) is considered highly important to cope with the water scarcity challenges in dry regions. Therefore, this study evaluated spatiotemporal characteristics of WUE and its related drivers in the Ω-shaped Region along the Yellow River aiming to provide decision support information for alleviating water shortages in this region. We employed the SBM-DEA (slacks-based measure-data envelopment analysis) model to calculate the WUE considering undesired outputs, analyze temporal and spatial variation based on GIS and statistical methods, and investigate the various factors that influence WUE based on the generalized method of moment (GMM) model. The results are as follows. (1) The WUE followed an increasing–decreasing-increasing trend, suggesting that the expanding agricultural and the second industrial structures are largely dominated by water-intensive activities which add further pressure on the water resources. (2) The spatial discrepancy of WUE among the cities is significant; however, the spatial pattern changes were stable during 2010 to 2019. (3) Analysis of influencing factors provides solutions for improving WUE in the Ω-shaped Region. Irrigation system and water conservancy infrastructure development and the acceleration of industrial transformation are necessary for improving the WUE in the Ω-shaped Region.
Mostrar más [+] Menos [-]Feasibility of growing Salicornia species in a coastal environment through planting date and density management in a direct seawater irrigation system
2022
Ranjbar, Gholamhassan | Pirasteh-Anosheh, Hadi | Dehghanie, Farhad | Keshtkar, Sardar | Race, Marco
Two field experiments were conducted to evaluate six Salicornia species (Salicornia bigelovii Torr., S. europaea L., S. persica Gorgan ecotype, S. persica Urmia ecotype, S. sinus persica Bushehr ecotype, and S. persica Central Plateau ecotype) at different planting dates and densities under irrigation with Persian Gulf water. Evaluated planting dates were 14 November and 18 December 2016 and 16 January, 8 February, 8 March, and 28 March 2017. Examined planting densities included 13, 20, and 40 plant m⁻². Only S. bigelovii and S. europaea produced measurable yield in all planting dates. The highest dry weight (651.1 gm⁻²) was obtained in S. sinus persica (Bu) planted on 8 February. Dry weight of S. bigelovii, S. europaea, S. sinus persica Bushehr, S. persica Central Plateau, S. persica Gorgan, and S. persica Urmia planted on 8 March were 174.2, 220.7, 542.5, 240.9, 158.0, and 147.5 g m⁻², respectively. The ash contents of S. bigelovii, S. europaea, S. sinus persica Bushehr, S. persica Central Plateau, S. persica Gorgan, and S. persica Urmia were 46.3%, 45.0%, 49.6%, 49.6%, 50.0%, and 53.1%, respectively. Sodium and chloride contents of different Salicornia species varied from 13–15% and 16–17%, respectively. The oilseed content of S. bigelovii and S. sinus persica Bushehr was about 24.0% for both species. The highest and lowest dry weight, from the second experiment, were for S. sinus persica Bushehr and S. persica Central Plateau, respectively, in all planting density. The highest dry weight equal to 1336.2 gm⁻² was obtained for S. sinus persica Bushehr in 40 plant m⁻² density. Under such conditions, forage production potential of Salicornia is more achievable rather than seed production. Nevertheless, high ash content is a serious constraint to direct consumption by livestock; therefore, determining the nutritional value of Salicornia fodder requires further evaluations.
Mostrar más [+] Menos [-]Optimizing cropping pattern to improve the performance of irrigation network using system dynamics—Powell algorithm
2022
Azadi, Saeed | Nozari, Hamed | Ghanbarian, Behzad | Marofi, Safar
One of the strategies for agricultural development is the optimal use of irrigation and drainage networks, which leads to higher productivity and economic benefits. In this regard, quantitative and qualitative studies of drainage water from networks are essential for efficient water management. In the present study, we develop a model using a system dynamics approach to simulate the cropping pattern of an irrigation and drainage network as well as the discharge and salinity of drainage water from network farms. We apply the Powell algorithm to optimize the economic profitability of cultivated crops by considering the salinity and discharge of drainage water from the fields. With three aims, i.e., (1) maximizing benefit–cost ratio, (2) minimizing drainage water salinity and discharge of network, and (3) economic and environmental considerations simultaneously, the optimization of cropping pattern within the Kosar irrigation and drainage network is performed. Results based on five consecutive years under different scenarios showed that some crops, such as watermelon, are not economically recommened for production due to high costs, water consumption, and low selling price causes environmental pollution. On the other hand, wheat, grain maize, silage maize, sorghum, and alfalfa have different conditions, and their production is suitable by considering all scenarios. By comparing with experimental data, we find that the proposed model is accurate to simulate and optimize the irrigation network and to detect its cropping pattern.
Mostrar más [+] Menos [-]Performance enhancement of solar photovoltaic system for roof top garden
2021
Prasad, Arani Rajendra | Shankar, Ramalingam | Patil, Chandrashekhar K. | Karthick, Alagar | Kumar, Amit | Rahim, Robbi
The photovoltaic (PV) for irrigation system is an emerging technology to harness the solar energy. The performance of the PV modules depends on the incident solar radiation, geographical location, and the surface temperature of the modules. The performance of the PV system needs to be monitored by manually or embedded controllers. The commercially available technologies for monitoring the system are costlier and need to be optimized. The Arduino controller is used to monitor the performance of the photovoltaic (PV) system in Coimbatore (11.016° N, 76.9558° E), Tamilnadu, India. The PV surface temperature is monitored and controlled by flowing the water above the module by setting the mean ambient temperature as a reference temperature 34 °C when the system exceeds the reference temperature. PV surface temperature is reduced up to 16°C thus improved the electrical efficiency by 17% compare to the reference module. The Arduino controller control the relay to switch on the motor to control the mass flow rate of the water at 0.0028kg/s. The various parameters are measured such as voltage, current, and solar radiation of the location and analyzed. The estimated cost of monitoring system and various sensor is 10$ which cost comparatively 50% lower than the other PV monitoring controllers. This method can be employed in the medium and large-scale irrigation system.
Mostrar más [+] Menos [-]Field Monitoring of 2010-Tsunami Impact on Agricultural Soils and Irrigation Waters: Central Chile
2016
Casanova, Manuel | Salazar, Osvaldo | Oyarzún, Irene | Tapia, Yasna | Fajardo, Mario
An in situ post tsunami study was conducted to assess the effect of water management and rainfalls in soil properties and water quality at a low-lying coastal area of central Chile affected by Mw8.8 Earthquake Tsunami the night of 27 February 2010. Soil samples were taken at two depths (0 to 20 and 20 to 40 cm) during 2010 and late 2012. Water quality in a local shallow well was also monitored in 2010 and 2012. High soil salinity was recorded 2 months later than tsunami occurs, closely associated to water-soluble chloride and cations (Cl⁻ > > Na⁺ > > Ca²⁺ > Mg²⁺ > K⁺), ionic toxicities, and vegetal inhibition (Vasconcellea pubescens) by less available water to plants. An initial reduction in soil pH due to ionic strength and coarse-textured class of soil was observed and the sodium adsorption ratio (SAR) in soil varied between 5.7 and 11.2 (mmol L⁻¹)⁰.⁵ showing to be saline. Although SARw values are very high (>18 (mmol L⁻¹)⁰.⁵), it does not exist risks of reduction on soil infiltration rates according to ECw (>5 dS m⁻¹) obtained. After 2 years, soil salinity was drastically reduced in the affected areas due to high soil permeability and natural attenuation (rainfalls and leaching effects), with sulfate and bicarbonate concentrations showing excessive values. Further, irrigation water quality returned to pre-tsunami situation, with only levels of sodium slightly exceeding desirable range from health point of view. Finally, it is suggested a proper design of irrigation systems before implementing other management practices.
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