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Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Big Data Research (2096-0271) is the property of Beijing Xintong Media Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(Objective) Over-extraction of groundwater over the past decades has resulted in shallow groundwater table dropping at an alarming rate in most regions in Hebei province. Reducing groundwater extraction for wheat winter irrigation has been proposed as a remedy to reverse this trend. Quantitative understanding of wheat yield reduction due to the restricted groundwater extraction and its consequence for groundwater dynamics is essential. Taking a piedmont plain of Taihang Mountain as an example, this paper investigates how to minimize the wheat yield loss by optimizing irrigation frequency when the irrigation amount is the same. (Method) The study was based on numerical simulation. We designed three scenarios with the irrigation amount kept the same at 90 mm, but the crop was irrigated at different frequencies. For each frequency, we simulated the winter wheat yield, variation in shallow groundwater table and soil water balance in the 0~200 cm of soil using the modified SWAT model. We divided the simulation area into 22 sub-basins, and the optimal irrigation frequency for each subbasin was calculated based on the index of crop-groundwater irrigation productivity. (Result) 1 Irrigating the crop twice, one at jointing and one at the heading stages, at equal irrigation amount (45 mm) gave the highest winter wheat yield, with the average yield reduced approximately by 20% compared to business-as-usual irrigation method. 2 Irrigating all 90mm of water at the jointing stage led to largest irrigation water leaching. 3 Increasing the irrigation frequency from two to three with the same irrigation amount in each (30 mm) did not noticeably change water leaching and evapotranspiration, but increased soil evaporation at the expense of transpiration. 4 To minimize yield reduction, 13 subbasins (approximately 54% of the studied area) should irrigate once only, 8 subbasins (approximately 40% of the studied area) should irrigate twice each with 45 mm of water, and one subbasin (approximately 6% of the studied area) should irrigate three times each with 30 mm of water. (Conclusion) Reducing groundwater extraction for winter wheat irrigation to 90 mm could mitigate shallow groundwater table falling by 60%~75% at the price of yield reduction of 20%~25%. To minimize the yield reduction, different regions should adjust the irrigation frequencies based on its heterogeneous aquifers. Optimizing irrigation frequency should consider the trade-off effect of irrigation on groundwater conservation and crop production, as well as irrigation water use efficiency. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Public Art is the property of Shanghai Fine Arts Publisher Ltd. co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Geomechanics is the property of Journal of Geomechanics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The maximum operating pressure for underground gas storage facilities designed for oil and gas reservoirs, both constructed and under construction in China, is currently set at the original formation pressure. There have yet to be successful cases of overpressure operation, which significantly impacts the economic benefits of converting depleted oil and gas reservoirs into underground gas storage facilities. This article aims to evaluate the maximum operating pressure and storage capacity of the Nanpu 1-29 gas storage facility from the perspective of the ultimate bearing capacity of cap layers and faults, with the goal of effectively enhancing the construction benefits of the facility. [Methods] The evaluation of the maximum operating pressure for the Nanpu 1-29 gas storage facility in eastern Hebei is based on the minimum principal stress measured in situ in the mining wells. Different effective porosity calculation methods are employed to quantitatively evaluate the effective storage capacity of gas and oil reservoirs, as well as the incremental capacity after pressure boosting operation, based on their development differences. [Results] The evaluation of the maximum operating pressure for the Nanpu 1-29 gas storage facility indicates that the minimum principal stress of the cap layers determined by the in-situ measurements in the mining wells is 34.00 MPa. Based on the tensile failure criteria determined by the minimum principal stress, the maximum operating pressure for the tensile failure of the cap layer is 27.20 MPa. Combined with the maximum safe injection pressure corresponding to shear failure of the cap layer (30.60 MPa) and the maximum safe injection pressure corresponding to unstable slip of the fault (27.60 MPa), the final maximum operating pressure for the Nanpu 1-29 gas storage facility is determined to be 27.20 MPa. Based on the effective storage capacity calculation model, considering factors such as the water content of the gas reservoir, residual water and edge porosity as well as the coefficient of influence, the efficiency of gas-driven fluid, and the utilization rate of oil-containing space, the maximum operating pressure increased from the original formation pressure of 22.50 MPa to 27.20 MPa. The practical storage capacity of the gas storage facility increased from 15.46x108 m³ to 18.14x108 m³, an increase of approximately 17.3%. [Conclusion] (1) The construction of gas storage facilities can be re-evaluated for the maximum operating pressure based on the minimum principal stress measured in situ in the mining wells, and overpressure design can be conducted under appropriate conditions. (2) Overpressure design can effectively increase storage capacity and improve the economic benefits of reservoir construction. [Significance] The research results have a certain reference value for the quantitative evaluation of the maximum operating pressure and storage capacity of other underground gas storage facilities, and are expected to significantly improve the economic benefits of overpressure-designed reservoir-type gas storage facilities in China. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rock & Mineral Analysis is the property of Editorial Board of Rock & Mineral Analysis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)