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Extending the Economic Life of the Ogallala Aquifer with Water Conservation Policies in the Texas Panhandle 被引量:1
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作者 Lal K. Almas Bridget L. Guerrero +3 位作者 David G. Lust Hina Fatima Rachna Tewari Robert Taylor 《Journal of Water Resource and Protection》 2017年第3期255-270,共16页
The continued decline in the availability of water from the Ogallala Aquifer in the Texas Panhandle has led to an increased interest in conservation policies designed to extend the life of the aquifer and sustain rura... The continued decline in the availability of water from the Ogallala Aquifer in the Texas Panhandle has led to an increased interest in conservation policies designed to extend the life of the aquifer and sustain rural economies. Four counties were chosen for evaluation. This study evaluates the effectiveness of five policies in terms of changes in the saturated thickness, crop mix, water use per acre, and the net present value of farm profits over a 60-year planning horizon. The dynamic optimization models were developed using GAMS for the baseline as well as one for all five of the policy alternatives for each county. Results indicate that the policy scenarios of biotechnology adoption and a water use restriction will conserve the most water among the policies analyzed. In terms of economic returns, the biotechnology adoption policy by far provides the greatest benefit to producers due to yield increases that are estimated with current annual growth rates in new seed varieties. The water use restriction policy, on the other hand, has the lowest net present value of returns, indicating that conservation is accompanied with significant costs to producers. The irrigation adoption technology scenario is the next best policy in terms of net present value of returns (following biotechnology);however, it ranks last in terms of reducing aquifer depletion. It is important to note that while the models do not perfectly predict the factors being evaluated, it is the basis for comparison between the policy scenarios which are important. These comparisons will aid policy makers in determining the most effective strategy to conserve water while simultaneously considering the economic costs to producers. In addition, the results of this study can be applied to other areas facing similar conditions, either currently or in the future, throughout the Texas Panhandle. 展开更多
关键词 GROUNDWATER Conservation IRRIGATED Agriculture Ogallala AQUIFER Texas panhandle Water Management Policy
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Saving Child Panhandlers
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作者 YIN PUMIN 《Beijing Review》 2011年第9期18-19,共2页
Netizens launch an Internet campaign helping authorities save children forced into begging for money On February 8, Peng Gaofeng reunited with his son who had been
关键词 Saving Child panhandlers
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绿僵菌NTL基因上游调控序列的克隆及分析 被引量:3
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作者 胡宗利 陈国平 +4 位作者 王中康 彭国雄 殷幼平 蔡绍皙 夏玉先 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第4期73-76,共4页
实验室已经克隆了金龟子绿僵菌中性海藻糖酶基因(NTL)的编码序列(GenBank登录号:AY557612),为了解该基因的上游调控信息,采用Panhandle Polymerase Chain Reaction Amplification方法获得了长为982bp的中性海藻糖酶基因上游序列。序列... 实验室已经克隆了金龟子绿僵菌中性海藻糖酶基因(NTL)的编码序列(GenBank登录号:AY557612),为了解该基因的上游调控信息,采用Panhandle Polymerase Chain Reaction Amplification方法获得了长为982bp的中性海藻糖酶基因上游序列。序列分析表明,该序列含有5个CAAT启动子元件和一个压力反应元件(CCCCT).经PCR和Southern杂交验证表明,利用panhandle PCR法成功地获得了金龟子绿僵菌CQMa102中性海藻糖酶基因上游序列,并且该基因在金龟子绿僵菌基因组中以单拷贝形式存在. 展开更多
关键词 panhandle PCR 金龟子绿僵菌 中性海藻糖酶基因(NTL)
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适用能源互联网非线性气流方程组的线性优化求解模型 被引量:8
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作者 贾文皓 丁涛 +3 位作者 曲明 白佳文 贺元康 陈天恩 《中国电机工程学报》 EI CSCD 北大核心 2020年第24期7938-7949,共12页
能源互联网通过多能源互补、协调优化实现能源高效利用和可再生能源消纳提升,具有重要的经济和环保意义。天然气、氢气等作为能源互联网的重要元素可通过管网进行传输,其传输过程需满足一定的非线性物理方程限制(如,Weymouth方程、Panha... 能源互联网通过多能源互补、协调优化实现能源高效利用和可再生能源消纳提升,具有重要的经济和环保意义。天然气、氢气等作为能源互联网的重要元素可通过管网进行传输,其传输过程需满足一定的非线性物理方程限制(如,Weymouth方程、Panhandle A方程、Panhandle B方程)。然而,非线性的气流方程给多能流的求解计算带来一定挑战。该文将非线性气流方程组精确同构成凸优化模型,从而使凸优化的最优解精确满足管道气流方程组,进一步采用分段线性化的方法将其转化为线性规划模型进行求解。选取多个天然气、氢气系统进行算例分析,给出的数值优化结果验证了模型的可行性与有效性,并在此基础上分析了不同分段数的选取对模型的求解精度与计算效率的影响。 展开更多
关键词 能源互联网 气流方程 Weymouth方程 panhandle方程 分段线性化
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Finger Millet: An Alternative Crop for the Southern High Plains
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作者 Prasanna H. Gowda P. V. Vara Prasad +2 位作者 Sangamesh V. Angadi Umesh M. Rangappa Pradeep Wagle 《American Journal of Plant Sciences》 2015年第16期2686-2691,共6页
In the Southern High Plains, dairies are expanding to take advantage of favorable climatic conditions. Currently, corn (Zea mays L.) and forage sorghum [Sorghum bicolor (L.) Moench] are the two major crops grown in th... In the Southern High Plains, dairies are expanding to take advantage of favorable climatic conditions. Currently, corn (Zea mays L.) and forage sorghum [Sorghum bicolor (L.) Moench] are the two major crops grown in the region to meet silage demands for the expanding dairy industry, but they have relatively large water requirements of about 840 and 690 mm, respectively, to achieve desirable results. With rising energy costs and declining water levels in the underlying Ogallala Aquifer, crops that use less water, like finger millet (Eleusine coracana (L.) Gaertn) could become alternate forage crops for dairies to corn or forage silage. In this study, we evaluated the adaptability of five finger millet accessions to the Southern High Plains and compared nutritional quality of their forage to that of corn and sorghum. Results indicated that finger millet can be grown in the Southern High Plains. Comparison of nutrient composition has shown that the quality of finger millet is relatively higher than that of corn and sorghum in terms of calcium, potassium, and phosphorus levels in their forage. However, potential forage yield of most commonly grown corn and sorghum in the region is higher than that of finger millet. Therefore, finger millet may provide a unique opportunity to improve the dairy-fed silage quality by mixing it with corn or sorghum silage while meeting the growing regional forage demand. Further field research is needed to measure its water requirements in the Southern High Plains. 展开更多
关键词 Ogallala AQUIFER Region SEMI-ARID FORAGE Texas panhandle
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