Assessment on eco-environmental quality of the Yellow River Basin by considering desertification index

Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact.

Coordination of Urbanization and Water Ecological Environment in Shayinghe River Basin,China

During the rapid industrialization and urbanization of China,urban agglomeration in river basin areas raises the problems of over-use of water resources and pollution of the water environment.Related research in China has mainly focused on the conflicts among economic growth,urban expansion and water resource shortages within admin-istrative boundaries.However,water environments are much more dependent on their physical boundaries than their administrative boundaries.Consistent with the nature of water environment,this study aims at analyzing coordination relationships between urban development and water environment changes within physical river basin boundaries.We chose the Shayinghe River Basin,China,as our case study area which is facing serious challenges related to water en-vironment protection.Then we classified 35 county-level administrative units into upstream,midstream and down-stream regions based on their physical characteristics;analyzed the coordination degree of urban agglomeration using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method;and constructed cooperative models using the Linear Programming (LP function) to simulate four scenarios of the coordination relationship be-tween urban population increase and water environment protection based on existing water resources and water pollu-tion data.The results show that the present coordinative situation in Shayinghe River Basin is not sustainable.In gen-eral,more than 50% administrative units are in the bad coordinative situation.In particular,the downstream region is under worse condition than the upstream and midstream regions.Cooperative models in scenario analyses indicate that the population scale set in existing urban master plannings is not coordinated with the water environment protection.To reach the goal of regional sustainable development,the total population needs to be controlled such that it will re-main at 4.5×10 7 or below by 2020 given the capacity of water environment.

Three Gorges Project:a project for ecological improvement and environmental protection in Yangtze River Basin

Seeking water and earning their livelihoods is the natural selection of human beings.Like other rivers on the earth,the Yangtze River is the birthplace of human civilization and survival.As an ecosystem,the Yangtze River Basin is evolving under the influences of natural factors and human activities.Because of soil erosion,pollution and human activities,the imbalance of secondary environment is exacerbated and the ecological environment has become more vulnerable,so it is urgent to mitigate and prevent the ecological crisis.The practice has proved that implementation of engineering measures is an effective way to improve the ecological environment.The Three Gorges Project (TGP) has a flood control storage capacity of 22.15 billion m 3,effectively storing the flood water upstream of Yichang,and protects 15 million people and 1.5 million hm 2 farmland.Furthermore,the project can prevent or slow down the sedimentation and shrinkage of the lakes in the middle Yangtze River such as Dongting Lake;with an average annual power generation of about 90 billion kW· h,it can significantly reduce the emissions of harmful gas like CO 2.In general,the construction of TGP is conducive to the ecological and environmental protection in the Yangtze River Basin and China,even the world.

A research on urban ecological environment evaluation system:Taking the Yangtze River Delta as an example

In this paper,we establish the evaluation index system of urban ecological environment from the perspective of urban ecological environment.We established two criteria level indicators and fourteen index layer program and calculate the level of each program index weight with the help of analytic hierarchy process.We take twenty-seven cities of Yangtze River Delta in 2013 and 2014 as an example and then analyze and rank them.The final results show that Shanghai,Suzhou,Hangzhou have relatively good ecological environment in the twenty-seven cities.

Conservation Grading of Water Ecological Spaces in the Muling River Basin

Along with the urban construction and industrial development, the original continuous riverway of the Muling River has been dammed into river sections of different lengths, which has seriously destroyed ecological environment of the basin. In view of this, it is urgent to protect water ecological environment of the basin. This paper took the national ecological environment conservation instructions as the guidance, combined with the administrative division, planning and actual conditions of the basin, proposed principles and schemes for the grading of water spaces in the basin, as well as the hierarchic control requirements, to provide instructions for the conservation of the river basin.

Analysis on Strategic Future of Application of Agricultural Ecological Source in Control on Agricultural Nonpoint Source Pollution in Xi River Area in Guangxi

Non-point source pollution has become a hot issue on aquatic ecological environment at home and abroad. The research analyzed the challenges confronted by Xi River and proposed to construct agricultural ecological source in middle and upper reaches of the Xi River from the perspectives of scientific layout, legal construction, routine monitoring, technology integration, and coordination system in order to promote sustainable development of eco-environment in Xi River.

Ecological health analysis of wetlands in the middle reaches of Yangtze River under changing environment

Changes in wetland ecosystems have a critical impact on the local ecology and species diversity.Different development scenarios and policies are key factors influencing their changes.Therefore,we studied changes of wetlands in the middle Yangtze River basin(MYRB)in 2001-2020,and a patch-generated land use simulation(PLUS)model and random forest(RF)method were applied to predict and analyze the changes under different scenarios in the MYRB in the future(i.e.2035-2095).The results indicated that:(1)The regions with high wetland proportions were concentrated in the central and eastern MYRB in 2001-2020,with a 1.5%decrease in overall wetland area;(2)The RF could simulate the future ecological quality with training and testing accuracies of 0.98 and 0.92,respectively;(3)Remote Sensing Ecological Index(RSEI)less than 0.5 in the central and eastern regions and 13.3%reduction in the northwest in the SSP245 scenario.In general,the study provides a basis for future regional studies of ecosystem quality and provides data to support wetland conservation and management.

Comparative study of carbonic anhydrase activity in waters among different geological eco-environments of Yangtze River basin and its ecological significance

This study provides the presence of carbonic anhydrase（CA） activity in waters of the Yangtze River basin, China, as well as the correlation of CA activity with HCO-3 concentration and CO2 sink flux. Different degrees of CA activity could be detected in almost all of the water samples from different geological eco-environments in all four seasons. The CA activity of water samples from karst areas was significantly higher than from non-karst areas（PP3-concentration（r = 0.672, P2 sink flux（r = 0.602, P = 0.076） in karst areas. This suggests that CA in waters might have a promoting effect on carbon sinks for atmospheric CO2 in karst river basins. In conditions of similar geological type, higher CA activity was generally detected in water samples taken from areas that exhibited better eco-environments, implying that the CA activity index of waters could be used as an indicator for monitoring ecological environments and protection of river basins. These findings suggest that the role of CA in waters in the karst carbon sink potential of river basins is worthy of further in-depth studies.

Mechanism of Ecological Compensating and Carbon Sink Trade in Qinghai-Tibet Plateau

The Tibetan, Han and other ethnic people in Tibetan Autonomous Region labored hard to protect the forests and steppes and produce invisible ecological products. The forests and steppes in Qinghai -Tibet Plateau conserved water and added the Jinsha River. In order to achieve sustainable development, it needs to construct compensating mechanism inter Provinces between the upper Yangtze River and the middle and lower Yangtze River, to implement carbon sink trading, and to assist farmers and herdsmen in the Tibet to get rich as soon as possible.

永定河流域水文演变与多水源联合优化调度

水资源是保护修复永定河生态环境功能、维护河流生命健康的控制性因素。永定河流域水资源极为紧缺,且地表水资源量呈显著衰减态势。为实现紧缺严苛的水资源条件下永定河生态水量的有效保障,系统解析了流域水文演变特征,核算了分河段基本生态水量和多水源生态补水潜力,建立了耦合水资源供用耗排过程和水工程群联合运用的多水源优化调度模型,提出了常规和极端情况下的多水源生态水量调度方案和基于降水年型研判的调度方案运用方式。研究成果为有效保障永定河生态水量、提升应对变化环境的韧性提供了关键方法和模型,为华北地区其他河流生态保护修复和综合治理提供技术参考。

长江流域微塑料生态风险综合评估

建立了涵盖长江流域43个城市、366个采样点的微塑料数据集来探究微塑料空间分布变化,并基于二维风险评估矩阵和蒙特卡洛模拟分别评估流域内部各采样点微塑料的绝对生态风险和流域整体微塑料的相对生态风险,进而确定了长江流域微塑料的优先控制地区和优先控制因子。结果表明:长江流域微塑料丰度平均值为(2.52±11.60)万个/m^(3),生产生活消费和船舶运输等人为因素、地形地势等自然因素可能是造成其分布不均的原因;长江流域各采样点所在城市微塑料的绝对生态风险指数范围为1~20,应重点关注鄱阳湖流域和太湖流域的微塑料生态风险;在相对生态风险评估中,流域内90.8%的微塑料污染负荷风险处于低风险等级,63.4%的聚合物危害风险处于高风险等级,65.5%的潜在生态风险处于低风险等级,微塑料丰度、聚氯乙烯和聚氨酯对生态风险的贡献较高。

“三水”统筹的流域水生态环境分区管控技术与实践

基于“三水”(水生态、水环境、水资源)统筹,开展流域空间精细化管控对推进新时代流域协同保护与治理具有重要意义。按照“‘三水’问题识别—‘三水’分区划定—质量目标确定—管控单元集成”的思路,构建了流域水生态环境分区管控技术方法。以白洋淀流域为实践对象,识别出流域性突出生态环境问题;衔接现有水生态环境管理分区与政策要求,划定生态保护红线、环境质量底线及资源利用上线;明确“三水”分区域差异化生态环境管理目标与资源环境承载约束,聚类叠“三水”分区并综合划定水生态环境综合管控单元、制定结构化生态环境准入清单。

黄河流域水资源-生态-城市-产业协同演进研究

为考察黄河流域水资源-生态-城市-产业协同的动态演进及其地区差异和来源,基于2016—2020年黄河流域76个主要地级市数据,采用协同度模型、核密度估计和Dagum基尼系数及其分解方法进行实证测度。结果表明:处于初级、中级和良好协同的城市数量分别为30个、33个和13个。各城市协同度水平呈现上升趋势,但城市间绝对差异在扩大,相对差异在缩小;除呼包鄂榆城市群外,其他六大城市群协同度绝对差异均呈扩大趋势。黄河上游和下游内部差异呈下降趋势,中游内部差异呈上升趋势;上游和中游间差异最大,且呈现进一步扩大趋势,上游和下游间差异逐渐缩小。呼包鄂榆城市群群内差异最小,关中城市群群内差异最大;关中城市群与山东半岛城市群群间差异最小,晋中城市群与山东半岛城市群群间差异最大。未来应进一步加强要素协同、区域协同,发挥各地区动态比较优势,因地制宜推进黄河流域生态保护和高质量发展重大国家战略深入实施。

长江经济带水生态环境治理区域协同立法的检视及完善途径

为充分发挥法律对区域环境发展和利益协调的保障作用,基于长江经济带水生态环境治理现状对部分省市已出台的相关规范性文本进行了梳理。结果表明,各地采取的立法模式主要以松散型立法模式为主,尚存在松散型立法模式与水生态环境治理需求不匹配、区域间主体协调机制未建立、协同立法后评估和清理工作机制不完善等问题。因此提出了将现有的松散型立法模式转变为紧密型立法模式,构建区域协同立法利益协调机制和完备协同立法后评估和清理机制等长江经济带水生态环境治理区域协同立法的完善路径。

环境DNA技术发展及其在长江流域水生生态学领域的应用研究进展

长江流域鱼类资源丰富、生物多样性高。近年来,受人为干扰、环境变化等因素影响,鱼类资源急剧衰退,全面了解该流域水生生态学信息、进行长江大保护迫在眉睫。随着分子生物学技术的发展,环境DNA技术应运而生,其相比于传统调查方式更加高效、灵敏,应用领域更广;该技术的灵敏性使其非常适合于检测濒危物种、低密度物种入侵、瞬时和隐秘物种的存在,特别是当检测低密度物种的采样工作难以控制时,其敏感性、简便性和降低危害性的优势愈加显现出来。因此,该技术已被广泛应用于食品微生物、生物监测、群落生态学、古环境、保护生物学和生物入侵等领域的研究。介绍了环境DNA定义、发展史、研究方法与优劣势,在此基础上概述了其在长江流域水生生态学领域的应用研究进展,最后展望了环境DNA技术与环境RNA技术相结合的技术革新以及新一代测序手段、大数据及机器智能技术多技术结合助力该领域研究的前景,以期为长江流域持续性生态学监测提供借鉴和参考。

基于遥感生态指数改进模型的沱江流域生态环境质量时空变化及驱动力研究

[目的]沱江流域面临严重的水土流失、水环境污染和土壤侵蚀等生态环境问题,开展流域生态环境质量评价对推动长江上游生态环境保护和流域社会经济高质量可持续发展具有重要意义。[方法]基于谷歌地球引擎平台,选取2000-2020年的Landsat遥感影像,以绿度、湿度、热度、干度、生物丰度指数构建生态环境质量评价模型,采用变异系数、一元线性回归和空间自相关分析方法对流域内生态环境质量的时空演变格局进行分析,并运用最优参数地理探测器模型(optimal parameter geographic detector model,OPGD)对其驱动力进行探测。[结果](1)2000-2020年,沱江流域生态环境质量多年平均值为0.66,等级以良为主,占比为63.01%。成都周边区县、内江、自贡、泸州等城镇地区生态环境质量较差,呈现南北低中间高的空间分布格局。(2)沱江流域生态环境质量总体呈下降趋势,生态环境质量变差的趋势显著,轻微退化和显著退化面积占比分别为19.75%和5.88%。人口密度大,社会经济发展水平高的城镇化地区,生态环境质量以较高波动为主,占比为18.15%。(3)2000-2020年沱江流域全局自相关莫兰指数范围为0.769~0.870,主要分布在第1象限和第3象限,局部自相关的高-高集聚区和低-低集聚区范围随时间呈显著变化,景观斑块破碎化明显。(4)OPGD结果表明,土地利用类型、坡度、高程、夜间灯光为流域生态环境质量变化的主要驱动因子,人口密度、气温和GDP为次要驱动因子,降水量和坡向因子影响较小。土地利用类型与其他因子交互作用增强对流域内生态环境质量变化的影响。[结论]改进的遥感生态指数模型对开展区域生态环境质量评价提供新方法,研究结果为生态环境保护提供参考。

水网格局下流域生态流量保障调度研究——以永定河流域为例

水利部2022年起部署实施母亲河复苏行动,以生态流量和水量为保障目标,生态流量管理模式也转向以水量、流量和过程等多样化生态保障为目标的新模式。生态用水需求的多样化,对流域生态用水总量、水利工程调蓄能力提出了更高要求。在保证永定河流域防洪、供水安全前提下,充分发挥跨流域调水对流域生态流量的补偿作用,提出了水网格局下江河流域生态流量保障调度框架,包括生态流量保障目标确定、考虑跨流域调水的生态流量保障调度方案制定、考虑跨流域调水的生态流量保障调度方案执行3个方面,以永定河为例,分析了流域生态流量保障调度实践及效果,提出以贯通“调算—优化—优选”全过程的生态调度决策方法,构建以生态效益最优、补水效率最高、补水费用最小为调度目标的多目标生态流量优化调度模型,可为我国北方水资源短缺流域开展生态流量保障调度提供参考。

长江流域河湖生态流量监督管理标准体系研究

为适应生态文明建设、落实《长江保护法》关于生态流量管控的规定,亟需建立长江流域河湖生态流量监督管理标准体系。在阐述河湖生态流量监督管理标准体系建设必要性和相关标准发展现状的基础上,从生态流量管控目标的确定、生态流量泄放设施的实施、生态流量监测监控的建设、生态流量保障程度的评估、生态流量调度调控的应对等方面出发,探讨了河湖生态流量监督管理标准体系建设,使长江流域河湖生态流量监督管理都有统一可遵循的准则,切实保障河湖生态流量。研究成果对保护和改善长江流域生态环境具有重要意义。

松辽流域生态环境时空动态评价及驱动因素分析

目前,我国高度重视以流域为基础的生态文明建设。及时有效的评估流域生态环境质量时空变化并分析其驱动因素对于制定流域协同性保护以及以流域为基础的生态文明建设十分重要。本文基于以数据为关键要素的,依托于遥感产品得到的绿度指数、湿度指数、干度指数、热度指数四项指标运用主成分分析方法建立松辽流域生态环境评估模型,并探索生态环境质量变化情况及其原因。结果表明:①松辽流域的生态环境质量整体优良,呈“东北优,西南差”的空间分布。②2000-2020年,松辽流域生态质量总体呈变好局势。第一个十年生态质量得到巨大改善,第二个十年处于生态保护维护阶段。③从空间分布上看,生态评级较差及以下等级面积明显收缩,优良等级面积显著向外扩张。④人类的社会经济生产活动对于生态环境的质量评估有至关重要的作用,如何平衡社会经济生产与生态环境保护之间的关系是帮助生态环境恢复的关键。

双碳背景下流域横向生态补偿政策对碳排放的影响

基于2008—2021年长江经济带108个地级市面板数据,采用双重差分模型和中介效应模型,实证分析流域横向生态补偿政策对碳排放的影响及其作用机制。结果表明:流域横向生态补偿政策显著抑制碳排放量,政策实施力度每增加一个单位,碳排放量平均减少3.7701个单位,且经过一系列检验后结果仍然稳健;机制检验表明,政策实施通过提升金融发展水平和促进科学技术创新两条作用渠道实现碳减排;异质性分析结果验证政策实施效果受社会经济和创新创业双因素的影响,政策实施力度每增加一个单位,一般城市的碳排放量减少2.5230个单位,与低创新创业环境城市相比,高创新创业环境城市在碳减排效果上表现出更明显的优势。据此,建议中小流域因城施策,在推广创新技术和建立监测评估机制、强化政策和资金投入等方面予以支持。