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871.
[目的] 分析淤地坝拦泥蓄水及其水资源利用潜力,为淤地坝水资源利用及管理提供依据。[方法] 本文通过调查法对甘肃省多沙粗沙区淤地坝建设现状、拦沙数量及空间分布、水资源利用效益和利用潜力进行分析。[结果] 截至2019年底甘肃省共建成淤地坝1 600座,其中大、中、小型坝各为559,452,589座;坝控面积4 101 km2,总库容4.82×108 m3,其中设计拦泥库容2.29×108 m3。目前拦泥库容1.43×108 m3,占设计拦泥库容的62.37%;拦泥库容中,大、中、小型坝各占80.86%,13.21%和5.93%;泾河流域、黄河干流、渭河流域、洮河流域各占71.46%,13.91%,12.72%,1.91%。由于流域产沙量减少,大型坝平均淤积17 a后(平均设计淤积年限15 a)剩余拦泥库容占设计拦泥库容的43.88%;中型坝平均淤积后(平均设计淤积年限10 a)剩余拦泥库容占设计拦泥库容的38.81%。全省淤地坝剩余拦泥库容8.62×107 m3,可作为今后蓄水利用的潜在库容。目前,淤地坝蓄水主要用于应急抗旱、农业及果园高效节水灌溉、土地多种经营及经济综合开发、畜禽养殖、淤地坝田园综合开发利用等。庆阳、平凉、天水和定西市安定区今后可开发用于人饮备用水源地、提灌补灌工程水源地、水体养殖(鱼塘)的淤地坝数量共147座。[结论] 为满足当地乡村振兴与高质量发展对淤地坝的社会需求,对有蓄水用水需求的区域,应提高新建坝的设计标准,建设可长期蓄水的高标准淤地坝;对已建成的大中型淤地坝进行提质改造,保证淤地坝坝体、防洪及水资源利用的安全性,同时建立淤地坝风险管控预警机制,有效化解缺水地区淤地坝蓄水用水与防汛管理的矛盾。  相似文献   
872.
[目的]研究新时期国际、国内科技和气候变化背景条件下中国沙漠地区综合治理的现状、问题及发展战略,为制定沙漠地区生态保护、资源合理开发利用规划和有关科学研究提供参考。[方法]以中国沙漠地区为研究区,分析了其分布与中国国情、气候变化和碳中和之间关系。基于新时期中国沙漠治理及生态恢复、沙漠资源开发利用等领域的最新研究进展,针对目前中国沙漠地区综合治理中存在的生态环境破坏等问题,提出了中国沙漠地区的发展战略。[结果]阐明了新时期中国沙漠地区的发展战略、基本原则及设计理念,提出中国沙漠地区综合发展战略及其实施路径、目标及愿景规划,并讨论了它与国家总体发展战略和世界大趋势之间的关系。[结论]在新形势下,很有必要对沙漠地区重新定位,在生态优先的原则下,科学充分地发掘沙漠地区的综合潜能,使之为中华民族伟大复兴服务,为构建人类命运共同体贡献中国智慧和力量。  相似文献   
873.
基于湿润指数,利用黄河流域及周边1960-2020年113个气象站点日值气候数据,通过气候倾向率、Morlet小波、简单相关分析和Hurst指数等方法,分析近61a黄河流域干湿状况时空演变特征,预估黄河流域未来干湿变化趋势,以期为流域防旱减灾、合理利用气候资源提供科学依据。结果表明:(1)空间上,黄河流域年和季节湿润指数呈现为东南部高、西北部低。流域年、春秋两季以变干为主,湿润指数呈显著下降的站点占总站点的比例分别为5.31%、7.96%、6.19%;流域夏、冬季以变湿为主,湿润指数呈显著上升的站点占比分别为10.62%、13.27%。(2)年际变化上,1960-2020年黄河流域年和季节湿润指数均无显著变化趋势。流域全年、春、夏、秋、冬季分别处于半湿润、半干旱、半湿润、半湿润和半干旱状态。黄河流域年和季节湿润指数存在多时间尺度的周期振荡特征,第一主周期分别为3a、26a、14a、3a和15a。(3)降水量、相对湿度与湿润指数呈极显著正相关,日照时数与湿润指数呈极显著负相关,均为黄河流域湿润指数的主要驱动因素。(4)黄河流域年和季节湿润指数的Hurst指数均大于0.50,表明流域年、春季和秋季气候将持续变干,夏季和冬季气候将持续变湿。  相似文献   
874.
为提高生姜产量和品质,给甘肃省生姜产业的发展提供技术支撑,结合生姜栽培的生产实践,总结出了生姜种植技术,包括品种选择、姜种催芽、整地施肥、田间管理、病虫害防治、采收等环节。  相似文献   
875.
As important freshwater resources in alpine basins, glaciers and snow cover tend to decline due to climate warming, thus affecting the amount of water available downstream and even regional economic development. However, impact assessments of the economic losses caused by reductions in freshwater supply are quite limited. This study aims to project changes in glacier meltwater and snowmelt of the Urumqi River in the Tianshan Mountains under future climate change scenarios (RCP2.6 (RCP, Representative Concentration Pathway), RCP4.5, and RCP8.5) by applying a hydrological model and estimate the economic losses from future meltwater reduction for industrial, agricultural, service, and domestic water uses combined with the present value method for the 2030s, 2050s, 2070s, and 2090s. The results indicate that total annual glacier meltwater and snowmelt will decrease by 65.6% and 74.5% under the RCP4.5 and RCP8.5 scenarios by the 2090s relative to the baseline period (1980-2010), respectively. Compared to the RCP2.6 scenario, the projected economic loss values of total water use from reduced glacier meltwater and snowmelt under the RCP8.5 scenario will increase by 435.10×106 and 537.20×106 CNY in the 2050s and 2090s, respectively, and the cumulative economic loss value for 2099 is approximately 2124.00×106 CNY. We also find that the industrial and agricultural sectors would likely face the largest and smallest economic losses, respectively. The economic loss value of snowmelt in different sectorial sectors is greater than that of glacier meltwater. These findings highlight the need for climate mitigation actions, industrial transformation, and rational water allocation to be considered in decision-making in the Tianshan Mountains in the future.  相似文献   
876.
Topography plays an important role in determining the glacier changes. However, topography has often been oversimplified in the studies of the glacier changes. No systematic studies have been conducted to evaluate the relationship between the glacier changes and topographic features. The present study provided a detailed insight into the changes in the two branches (east branch and west branch) of Urumqi Glacier No. 1 in the Chinese Tianshan Mountains since 1993 and systematically discussed the effect of topography on the glacier parameters. This study analyzed comprehensive recently observed data (from 1992/1993 to 2018/2019), including mass balance, ice thickness, surface elevation, ice velocity, terminus, and area, and then determined the differences in the changes of the two branches and explored the effect of topography on the glacier changes. We also applied a topographic solar radiation model to analyze the influence of topography on the incoming shortwave radiation (SWin) across the entire glacier, focusing on the difference in the SWin between the two branches. The glacier mass balance of the east branch was more negative than that of the west branch from 1992/1993 to 2018/2019, and this was mainly attributed to the lower average altitude of the east branch. Compared with the west branch, the decrease rate of the ice velocity was lower in the east branch owing to its relatively increased slope. The narrow shape of the west branch and its southeast aspect in the earlier period resulted in a larger glacier terminus retreat of the west branch. The spatial variability of the SWin across the glacier surface became much larger as altitude increased. The SWin received by the east branch was slightly larger than that received by the west branch, and the northern aspect could receive more SWin, leading to glacier melting. In the future, the difference of the glacier changes between the two branches will continue to exist due to their topographic differences. This work is fundamental to understanding how topographic features affect the glacier changes, and provides information for building different types of relationship between the glacier area and ice volume to promote further studies on the basin-scale glacier classification.  相似文献   
877.
Glaciers are known as natural 'solid reservoirs', and they play a dual role between the composition of water resources and the river runoff regulation in arid and semi-arid areas of China. In this study, we used in situ observation data from Urumqi Glacier No. 1, Xinjiang Uygur Autonomous Region, in combination with meteorological data from stations and a digital elevation model, to develop a distributed degree-day model for glaciers in the Urumqi River Basin to simulate glacier mass balance processes and quantify their effect on streamflow during 1980-2020. The results indicate that the mass loss and the equilibrium line altitude (ELA) of glaciers in the last 41 years had an increasing trend, with the average mass balance and ELA being -0.85 (±0.32) m w.e./a (meter water-equivalent per year) and 4188 m a.s.l., respectively. The glacier mass loss has increased significantly during 1999-2020, mostly due to the increase in temperature and the extension of ablation season. During 1980-2011, the average annual glacier meltwater runoff in the Urumqi River Basin was 0.48×108 m3, accounting for 18.56% of the total streamflow. We found that the annual streamflow in different catchments in the Urumqi River Basin had a strong response to the changes in glacier mass balance, especially from July to August, and the glacier meltwater runoff increased significantly. In summary, it is quite possible that the results of this research can provide a reference for the study of glacier water resources in glacier-recharged basins in arid and semi-arid areas.  相似文献   
878.
为阐明施氮对枸杞的光合日变化特性及产量的影响,选择黑果枸杞(Lycium ruthenicum)和宁夏枸杞(Lycium barbarum)两个物种,设置0(CK)、50(F1)、100(F2)、150(F3)和200 (F4)g·株-1共5个施氮处理,研究移栽至干旱区甘肃省武威市的黑果枸杞和宁夏枸杞的净光合速率(net photosynthetic rate,Pn)、蒸腾速率(transpiration rate,Tr)、气孔导度(stomatal conductance,Gs)、胞间CO2浓度(intercellular CO2 concentration,Ci)、瞬时水分利用率(water use efficiency,WUE)和气孔限制值(stomatal limitation,Ls)的日变化及产量,并通过光合作用提高产量的角度对最佳施氮量进行拟合。结果表明,施氮能提高黑果枸杞和宁夏枸杞1 d内各时间段的Pn、Tr、Gs、WUE及产量,降低两种枸杞1 d内各时间段的Ci和Ls,有利于光合作用的进行;施氮对黑果枸杞各光合参数的影响较宁夏枸杞更显著。F3处理下黑果枸杞的日平均净光合速率(PnA)和产量最佳,分别为9842 μmol·m-2·s-1和173.621 g;施氮187.730 g·株-1的宁夏枸杞的PnA最佳,为11.616 μmol·m-2·s-1;F3处理的宁夏枸杞的产量最佳,为205.264 g·株-1。因此,施氮150 g·株-1有利于提高黑果枸杞和宁夏枸杞的光合作用,进而获得最大产量。  相似文献   
879.
靳艳玲  赵海  曾凡逵 《农学学报》2021,11(11):98-103
中国是世界第一大甘薯生产国,目前甘薯主要加工利用方式为生产淀粉及淀粉制品,但加工过程中伴随淀粉同时产生大量副产物——甘薯渣,因未能得到有效的回收利用而导致了农村面源环境污染,已成为制约甘薯淀粉加工业可持续发展的主要因素之一。为了探讨甘薯渣资源化利用的方式,本文以其基本成分作为切入点,分析了近年来针对甘薯渣中淀粉、纤维、果胶、蛋白质以及全原料开展高值化利用的技术要点、主要产品及应用效果等,并提出了避免二次污染、开展全组分生物炼制、重视可溶性膳食纤维以及着力攻关鲜甘薯渣配套利用技术的建议。  相似文献   
880.
采用二因子旋转回归设计,研究了灌溉和N肥用量对玉米生育期、生物量和产量的影响。结果表明,在干旱的沙坡头绿洲农田生态系统中,水分是影响玉米生长的首要因素,在一定的灌溉范围内,灌水量的增加能促使玉米生育期提前、生物量和产量增加;N肥对玉米性状的影响较灌溉处于次要地位,但是在一定的灌溉条件下,N肥对玉米的生长仍然起重要作用,大喇叭口期追肥的作用最为显著。  相似文献   
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