Analysis of ecological effects of comprehensive treatment in the Tarim River Basin using remote sensing data

Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River.

Scale effects of eroded sediment transport in Wujiang River Basin, Guizhou Province, China

In recent years, research on spatial scale and scale transformation of eroded sediment transport has become a forefront field in current soil erosion research, but there are very few studies on the scale effect problem in Karst regions of China. Here we quantitatively extracted five main factors influencing soil erosion, namely rainfall erosivity, soil erodibility, vegetative cover and management, soil and water conservation, and slope length and steepness. Regression relations were built between these factors and also the sediment transport modulus and drainage area, so as to initially analyze and discuss scale effects on sediment transport in the Wujiang River Basin(WRB). The size and extent of soil erosion influencing factors in the WRB were gauged from: Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM), precipitation data, land use, soil type and Normalized Difference Vegetation Index(NDVI) data from Global Inventory Modeling and Mapping Studies(GIMMS) or Advanced Very High Resolution Radiometer(AVHRR), and observed data from hydrometric stations. We find that scaling effects exist between the sediment transport modulus and the drainage area. Scaling effects are expressed after logarithmic transformation by a quadratic function regression relationship where the sediment transport modulus increases before decreasing, alongside changes in the drainage area. Among the five factors influencing soil erosion, slope length and steepness increases first and then decreases, alongside changes in the drainage area, and are the main factors determining the relationship between sediment transport modulus and drainage area. To eliminate the influence of scale effects on our results, we mapped the sediment yield modulus of the entire WRB, adopting a 1 000 km^2 standard area with a smaller fitting error for all sub-basins, and using the common Kriging interpolation method.

Effects of reservoirs on seasonal discharge of Irtysh River measured by Lepage test

The Irtysh River is an intemational river partially joining the territories of China, Kazakhstan, and Russia. Cascade reservoirs have been constructed in the upper reaches of the river and their effects on the seasonal discharge of the middle and lower reaches were analyzed considering the mean and dispersion of the seasonal discharge. The Lepage test, which is a nonparametric, two-sample test for detecting location and dispersion, was used to measure the significance of difference between the pre-dam and post-dam seasonal discharge. The results show that the reservoirs＇ effects on the seasonal discharge varied with the season. In the middle reaches of the river, the summer and autumn discharge decreased significantly and their inter-annual variabilities also decreased significantly. The summer and autumn precipitation over the Irtysh River Basin changed little before and after the operation of the reservoir, which indicates that the discharge changes mainly due to water storage of the reservoirs. The reservoirs store water in summer and autumn and store more water in a wet year, which leads to the reduction of the mean and dispersion of the summer and autumn discharge. The winter discharge increased significantly because the reservoirs released water for power generation. The spring discharge changed slightly. In the lower reaches, only the winter discharge increased significantly, and the other seasonal discharge changed slightly. The reservoirs＇ effects on the seasonal discharge are more significant in the middle reaches than in the lower reaches.

An Evaluation of Artificial Fish Nest for Assessment Enhancement Effects of Fishery Resources of in Xiangjiang River

Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × 4 and a unit frame area of 60 m2. A total of 58,201 eggs were collected by 24 monitoring times, of which 30,441 were from Lukou and 27,760 from Hengyang. 3831 fish eggs identify 8 fish species using morphological or molecular biological methods. The results showed that the number of eggs peaked from the 8th day to the 24th day after the nest entered the water, and then decreased rapidly. There was significant negative correlation between egg number in per m2 fish nest and days of fish nest (P < 0.01). The economic benefits of artificial fish nests were RMB 11.81 million. The artificial fish nest can not only increase the population of fish, but also has significant economic benefits.

河湖长制背景下复苏河湖生态环境路径探析

河湖长制是一项基于我国政治制度和国家治理结构而设计的重大制度创新,实施7年多来,取得了显著成效。复苏河湖生态环境是推动新阶段水利高质量发展的六条实施路径之一,不仅涉及工程技术问题,更重要的是面临着理念、制度和管理层面突破创新的挑战。在分析河湖长制制度效能的基础上,从体制机制、保护治理和制度政策3个维度探讨了复苏河湖生态环境的路径选择问题。研究建议:以河湖长制为复苏河湖生态环境的有力手段和重要的体制机制保障,将河湖长制的制度优势转化为河湖治理效能,统筹各方力量共同推进河湖保护治理;以建设幸福河湖为目标,通过系统治理、综合治理、源头治理,推动复苏河湖生态环境各项任务落实;将健全复苏河湖生态环境的制度和标准体系作为复苏河湖生态环境的政策制度路径。

水土保持生态建设下的黄土高原典型流域水沙响应

为探讨黄土高原多沙粗沙区流域水沙关系演变特征及其对水土流失治理的响应,以黄河中游无定河流域为研究对象,综合采用水沙关系曲线、数理统计等多种方法,系统分析1956—2019年间无定河流域水沙关系多时间尺度演变特征及其与水土流失治理的协同响应。研究结果表明:1)研究时段内,无定河流域年径流及年输沙量呈锐减趋势(P<0.05),且均在1970年左右发生减少突变;2)流域水沙关系在年际和场次洪水尺度上均发生深刻变化。2010年以后,暴雨频发导致流域内侵蚀物源头供应明显增加,流域河道泥沙输送能力小幅提高;3)水土保持措施实施对流域水沙锐减影响较大。2000年前后在相似降雨条件下,单位降雨量径流量和单位降雨量输沙量较20世纪70年代减少47%和62%。水土保持措施面积增加与流域径流输沙减少呈现较好的一致性,流域水土流失治理在提高黄河多沙粗沙区流域下垫面抗侵蚀能力等方面发挥重要作用。研究结果可为科学认知区域水土流失治理成效及入黄泥沙锐减成因提供参考。

基于河网水动力模型的水系连通性对水环境质量的影响分析研究

平原河网地区地势平坦流速较缓,水体抗污染能力弱,改善水系连通性对水环境质量提升至关重要。以水系连通性较差的盛泽镇跃进联圩为研究对象,通过开展引调水试验,构建圩区河网水动力模型,探索圩区水利工作调度运行规则、河网水系连通方法以及相应的水环境变化规律。研究以水龄作为水系连通性的一种时间尺度参量,建立了跃进联圩水动力-水质-水龄的河网水环境模型,模拟了5种引调水方案下,圩内水系连通性及水质改善情况,并构建了压力、状态与响应的引调水连通效果评估体系,实现了对水系连通性变化与水环境改善水平的定量分析。结果表明:从水体交换时长来看,研究区域主要河道水体交换时间在5天以内,水体连通性越好的河道,水龄越短;从水质指标变化来看,调水实验中圩内的水环境氨氮变化最为明显,对引调水响应度高,模拟结果显示水龄与氨氮浓度变化趋势基本一致,水体连通性越好,水龄越短,有利于氨氮的削减;从引调水方案来看,单一调度方式对圩内水系连通性改善能力有限,特别是在河网内水体流动性弱的区域,同时使得圩区内水体流动性差异增大,更容易造成河网内水系连通性以及水质的空间分布差异,形成局部的滞水区或死水区。因此,采用多源引水与多区域排水相配合的调度方式,可以加强水系连通性,改善水环境质量。

长三角地区联合河长制政策效果模拟与仿真研究

基于DPSIR理论,运用系统动力学的方法,构建长三角地区联合河长制政策仿真模型,从水资源保护、水污染防治、水生态修复、水环境治理等维度,通过模拟与仿真,纵横对比联合河长制的政策效果,分析联合河长制政策2023—2035年的政策效果。研究结果表明:(1)长三角地区联合河长制政策整体效果比较显著,在水资源保护、水污染防治、水生态修复、水环境治理四个方面的政策效果明显;(2)自2023年起的未来十多年,联合河长制政策效果呈减弱趋势,并不具有较强的可持续性,要持续实现联合河长制较好的政策效果,需要进一步深化完善与联合河长制政策相配套的协作机制、动力机制、保障机制、监督机制等政策体系。论文为解决长三角地区流域治理中上下游,干支流、左右岸不协同,优化流域单元与行政单元间的“条”“块”协同机制,推进长三角地区协同大保护与高质量发展具有十分重要的理论意义和实践价值。

Downstream effects of reservoirs in areas suffering from water deficiency-the case of Hutuo River, China

The Hutuo River is located in the semi-arid areas in China. Due to fat of water resources in these areas, changes in flow regime, mainly reduction in runoff downstream from the reservoirs, have been tremendous. As a result of decrease in flow power and sediment load, the post-dam river showed a less change in channel morphology and the change varied reach by reach. Comparatively, the channel shrinkage may contribute to the flood disasters in the lower reaches of the river in recent years. An obvious increase of channel's hydraulic roughness, the main cause for reduction of flood transmission capacity of the channel, is attributed to vegetation encroachment in the channel. The effects of reservoir construction on ground water level and other environmental aspects are also discussed in the paper.

黄河口泥沙的治理实践与评价

基于1855年以来黄河口的来沙量及其不同时期河口泥沙的输移分布特征,从入海流路、防洪安全、下游河道淤积和航道建设等4个方面对黄河口泥沙的灾害效应进行了论证分析。在总结黄河口泥沙治理历史的基础上,从防洪工程体系建设、强化河口河段泄洪排沙能力、减少河口来沙等3个方面对20世纪70年代中期以来黄河口所采取的泥沙处理对策进行了概括总结。结合国内外相关典型河口泥沙的治理经验和发展态势,从水沙关系调控、入海流路格局优化、利用海洋动力输沙和泥沙资源化利用等方面提出了今后黄河口泥沙的治理方向和主要策略。

水稻驯化与中华文明的起源——中国地理教学中的思政教育

作为世界文化遗产,良渚文化确证了中华民族的5 000年文明史.这与水稻的起源密切有关.水稻起源的讨论始于19世纪,由瑞士植物学家阿方斯·德康多尔基于文献证据认为起源于中国和印度,历经不同国家学者的反复认证,起源于长江中下游已成基本共识.大致说来,水稻起源于10 000年前的长江中下游,后历经尝鲜、补充,直到5 000年前才正式成为当地食物供应的主体.大体上,10 000年前的上山遗址,表明了水稻的驯化和稻作农业的起源,仍然处在最初阶段.到了7 000~8 000年前的河姆渡文化时期,人类社会依然处于由采集狩猎向稻作农业社会的转变过程中,人类还没有进入到真正的稻作农业社会阶段.良渚文化时期,中国的长江下游地区已经进入到了稻作农业社会阶段,完成了从采集狩猎向稻作农业的转变过程.水稻和小麦为全球两大主粮.约10 000年前,小麦起源于两河流域,后扩散至埃及和印度河流域.在四大古文明中,唯有中华文明的生产基础是水稻,其余三个文明均是小麦.从西至东,古埃及文明、古两河文明、古印度文明以及中华文明(良渚文化),非常巧合的是它们均恰好位于北纬30°线上,体现出5 000年前古代文明出现的规律性.

小浪底水库减淤调度模式探讨

小浪底水库在黄河中下游防洪格局中发挥着重要作用,长期保持库区较大库容、延长拦沙运用期,对黄河防洪保安具有重大意义。基于小浪底水库运用以来入库水沙条件变化以及调度实践分析,提出了近期小浪底水库减淤调度模式:前汛期洪水期考虑下游河道淤积和主槽过流能力,尽量利用大流量过程开展降低水位排沙运用,冲刷库区河槽新增淤积物,以恢复河槽过流能力,保持库区高效输沙通道;水库排沙运用过后,运用水位宜不高于库区较大滩地滩面,利用河槽输沙调沙能够有效减缓滩面淤积;后汛期在保证防洪安全的前提下,根据上游来沙情况择机开展水库回蓄,尽早将库水位蓄至HH37断面附近滩面以上,利用HH37断面以上库段临时调沙,减缓滩面淤积。

Possible effect of climate changes on the coastal zone of the Yangtze River Delta

A coastal historical evolution of the Yangtze River Delta was discussed in this paper on the basis of the historical data of the coastal zone and an estimation was made for the future change of the coast The emphasis was put on the future climate change that will have influence on the sea wall, coastal navigation and freshwater resources in the Delta It was also pointed out that the global warming and precipitation increase in the Yangtze River Valley may exert more impact on the zone In addition, some measures describing how to adapt to the climate change and reduce its impact were put forward

Integrating Downstream Ecological, Social and Economic Effects of Hydropower to Hydraulic Modeling: A Review

Hydropower gains increasing importance as a steerable and controllable power source in a renewable energy mix and deregulated markets. Although hydropower produces fossil-free energy, it has a significant impact on the local environment. This review investigates the effects of flow alterations by hydropower on the downstream river system and the possibilities to integrate these effects into hydraulic modeling. The results show that various effects of flow regulation on the ecosystem, but also social and economic effects on related communities were observed in the last decades. The application of hydraulic models for investigations of ecological effects is common. Especially hydraulic effects and effects on fish were extensively modeled with the help of hydraulic 1D- and 2D-simulations. Current applications to investigate social and economic effects integrated into hydraulic modeling are meanwhile limited. Approaches to realizing this integration are presented. Further research on the economic valuation of ecosystems and integration of social and economic effects to hydraulic models is necessary to develop holistic tools to support decision-making on sustainable hydropower.

超薄层稠油油藏有效开发方式研究

大庆WE区块萨尔图稠油油藏属于低丰度超薄层稠油油藏,此前仅开展过小规模蒸汽吞吐现场试验,开发程度较低,经济效益不过关,未形成有效的开发技术体系,不同砂体规模布井模式及有效动用方式不明确。为此,基于储层流体渗流特征,通过岩心驱油实验和数值模拟、经济评价研究,对比分析弹性开发、热水驱、蒸汽吞吐、弹性开发转蒸汽吞吐、蒸汽驱的开发效果,建立超薄层稠油油藏开发方式及布井模式优化设计方法,评价不同河道砂体规模下直井和水平井的井控储量,计算不同开发方式技术经济井距。结果表明:弹性开发有效期为240~300d,弹性开发转蒸汽吞吐采收率较高、内部收益率最高。将研究成果用于指导区块分四期编制开发布井方案,设计开发井493口(水平井155口),设计产能32.59×10^(4)t,河道宽度大于250m、有效厚度大于2.3m的区域部署水平井,河道宽度小于250m、有效厚度大于2.7m的区域部署直井,采用140m井距,采取前期弹性开发后期转蒸汽吞吐开发方式。截至目前已完钻并投产292口井,累积产油量32.7×10^(4)t,实现了当年增储、当年建产、当年拿油。

数字经济赋能长三角制造业高质量发展——空间溢出与机制识别

基于2011—2021年长三角地区41个城市的面板数据,采用主成分分析法和空间杜宾模型等方法实证检验数字经济对长三角制造业高质量发展的赋能效应及多重路径的综合作用效果。结果表明:长三角地区数字经济不仅能显著赋能本地制造业高质量发展,还对邻近地区制造业高质量发展有显著的促进作用,空间溢出效应占比为79.4%;数字经济赋能制造业高质量发展主要依赖于人力资本和物质资本积累,且人力资本与物质资本呈协同效应,消费能力路径与人力资本、物质资本均呈背离效应。

长江流域绿色金融、产业结构与低碳发展的协调效应测度研究

长江流域是中国经济发展的重要支撑和国家生态安全的关键区域。以长江沿岸的省份为研究对象,选取2012—2021年经济、产业等数据进行分析,研究绿色金融、产业结构与低碳发展三者耦合协调的状况。结果表明,目前,长江流域的产业结构仍以传统的重工业和高能耗型产业为主,碳排放量较高,资源利用率较低。绿色金融的综合得分较低,但呈现上升的趋势。

微塑料在黄河流域的污染现状与治理研究进展

我国是世界最大的塑料制品生产和消费国,而黄河流域人口密集,其水质安全极其重要。针对黄河流域水体中微塑料,通过调研大量黄河流域微塑料污染相关文献,从微塑料的来源特征、形状与粒径、空间与季节分布特征等方面系统归纳了黄河流域微塑料污染现状,结合不同地区人口密度、地理环境和季节变化进行深入分析,进一步对比了黄河流域和国内其他主要河流微塑料污染状况,结果表明:微塑料在黄河流域的丰度整体呈现西低东高的态势,黄河流域干流微塑料粒径大部分集中在200μm以下,黄河流域枯水期微塑料丰度大于丰水期的。此外,还系统阐述了微塑料的生物毒性及治理技术研究进展。

产业链韧性对经济高质量发展的影响

基于2011—2022年长三角地区41个城市的面板数据,运用计量模型,分析研究了产业链韧性对经济高质量发展的影响效果及作用机制,并构建空间杜宾模型探索了产业链韧性对经济高质量发展的空间效应影响。结果表明:产业链韧性对经济高质量发展有显著正向作用;产业链韧性可以通过产业结构升级和产业创新两条路径来促进经济高质量发展;产业链韧性对于都市圈内城市和区位更具优势的城市的经济高质量发展的促进效果更明显;产业链韧性提升对周边城市经济高质量发展存在正向溢出效应。认为应从产业链延链补链强链、改善创新环境、做大产业集群等方面提升产业链韧性,推动产业转型升级和产业创新,促进经济高质量发展。