Evaluation on Current Situation of the Water Ecology of the Main Rivers and Lakes in the Liaohe River Basin

In this paper,15 rivers and 10 lake reservoirs in the Liaohe River basin were taken as research objects. Based on six indexes: satisfaction situation of ecological water demand,standard-reaching rate of water quality in water function area,eutrophication index of lakes and reservoirs,longitudinal connectivity of rivers,reserve rate of important wetlands and status of important aquatic habitat,water ecological conditions of main rivers and lakes in the basin were evaluated. The results showed that the rivers with better ecology were mainly distributed in east mountainous area of Liaoning,such as the upper reaches of the Hunhe River and the Taizi River;the problems of water pollution,ecological water shortage and habitat shrinkage were widespread in the Liaohe River basin,and the situation of water ecological security in the Liaohe River basin still faced great pressure.

Study on the Countermeasures to Improve the Public Outdoor Leisure and Fitness Function on the Two Rivers and Four Banks in the Main Urban Area of Chongqing

The main urban area of Chongqing is surrounded by two rivers and set against each other.With its unique waterfront landscape,it has the resource conditions to become a leisure tourism destination.Intending to enhance people’s happiness,improve city quality,and promote Chongqing’s main urban area to become a tourist destination,this paper finds out the existing problems in the construction of public outdoor leisure and fitness facilities on the two rivers and four banks of Chongqing’s main urban area through investigation and analysis based on relevant experiences at home and abroad,takes the value chain theory as the guidance,and to find solutions to the problem.On this basis,combined with the law of economic operation,this paper puts forward the guiding ideology,principles,development goals,functional orientation,and development path for the improvement of public outdoor leisure and fitness on two rivers and four banks in the main city of Chongqing,and accordingly puts forward the policy system and guarantee measures for its improvement.

Change trend analysis of ammonia nitrogen in Nenjiang River main stream under fluctuating precipitation

将2004-2010年嫩江流域沿途13个气象站的降水量作为径流的主要考察因子，以嫩江最下游的自沙滩水环境监测站获得的氨氮监测数据为流域总体氨氮污染水平表征，分析了降水波动对嫩江流域氨氮污染变化的影响。结果表明，嫩江流域在年度内的氨氮质量浓度以枯水期最高，平均为（0．99±0．48）mg／L，在丰水期最低，平均为（O．58±0．08）mg／L。从年际总体变化趋势来看，2004-2010年嫩江流域氨氮浓度总体呈增加趋势。降水量的年内分布格局对嫩江流域氨氮浓度的影响在不同时期略有差别。在平水期，降水量变化对氨氮浓度的影响不显著；但在枯水期、丰水期，降水量的波动对氨氮浓度有较显著（Sig．〈O．05）的影响。从年尺度上看，随降水量增加，嫩江流域中氨氮浓度总体呈下降趋势。

TEXTUAL RESEARCH ON THE MAIN SOURCE OF THE CHANGJIANG RIVER

The Chinese people began to research the main source of the Changjiang (Yangtze) River 2,400 years ago. Limited by the scientific level, they did not discover it.The Tuotuo River was determined as the main source of the Changjiang River in the 1970s. However, this was not correct, because when comparing the length of the Tuotuo River with the Dam River, the glacier length at the headwaters was added to the Tuotuo River, resulting in that the Tuotuo River is 1 km longer than the Dam River, keeping in mind that the glacier can not be regarded as part of the river.In the summer of 1986, we investigated the source of the Changjiang River, we accurately measured the length of both the Tuotuo and Dam rivers, we discovered that the Dam River was 353.1 km long, and the Tuotuo River was 346.3 km long, the Dam River thus being 6.8 km longer than the Tuotuo River. The discharge of the Dam River is 196.18 m3/ sec., 2.6 times as large as that of the Tuotuo River, that of the Tuotuo River is 75.10 m3/sec. The

FUZZY COMPREHENSIVE EVALUATION OF CONTAINER TRANSPORTATION MODES ALONG THE CHANGJIANG RIVER MAIN LINE AND ITS DELTA AREA

The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in China. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifically in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.

Analysis of Micro Organic Compound Pollution in Major City River Reaches of the Main Stem of the Changjiang River

It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system.

Seasonal variation of tidal prism and energy in the Changjiang River estuary： a numerical study

Tidal rivers are intrinsically complex because tidal propagation is influenced by river discharge. This study aims to examine the seasonal variation of tidal prism and energy variance in the tidal river of the Changjiang(Yangtze) River estuary in China. In order to quantify the behaviour of river and tide,we use numerical modelling that has been validated using measured data. We conduct our analysis by quantifying the discharge and energy variance in separate components for both the river and the tide,during wet and dry seasons. We note various definitions of tidal prism and explore the difference between tidal discharge on the flood and ebb and tidal storage volume. The results show that the river discharge attenuates the tidal motion and reduces the tidal flood discharge but the tidal storage volume is approximately constant with different riverine discharge since part of the fresh water discharge is intercepted and captured in the estuary due to the backwater effect. It appears that the tidal discharge adjusts according to the variation of river discharge to keep a constant tidal storage volume. An analysis of the hydraulics shows that the transition from tidal dominance(at the mouth) to river dominance(upstream) depends on the location of tidal current reversal which varies from wet season to dry season. Duringthe wet season,the Changjiang River estuary is totally dominated by energy from fresh water discharge.

区域一体化能够促进城市高质量发展吗?--来自长三角一体化国家战略的准自然实验

以长三角一体化国家战略的实施为准自然实验,在探究政策对高质量发展影响机制的基础上,基于2011-2021年114个城市的样本数据,运用渐进双重差分模型评估了该政策对于高质量发展的影响。研究表明:长三角一体化国家战略总体上显著提高了城市的高质量发展水平,且主要体现在经济层面,部分体现在社会层面;长三角一体化国家战略对高质量发展的影响,在不同规模城市和不同市场一体化程度城市中存在显著差异;长三角一体化国家战略通过降低市场分割和产业同构促进城市的高质量发展;交通运输能力和技术水平在长三角一体化国家战略对城市高质量发展影响中发挥着正向的调节效应作用。长三角一体化国家战略的实施,为生态发展、兼顾小城市利益和政策推广拓展了空间。

农业生态效率的演变特征与空间收敛——基于黄河流域47个城市的实证

基于2000—2020年黄河流域47个地级市的面板数据,构建黄河流域农业生态效率的投入产出指标体系,运用非期望产出的超效率SBM模型测算各市的农业生态效率,结合GIS空间分析、Moran’s I指数、ML指数等方法分析农业生态效率的演变特征,并进行空间收敛性分析。结果表明:黄河流域农业生态效率水平整体偏低,但正处于由低水平迈向高水平的“爬坡”阶段,其中下游地区的效率增长最快;效率增长的主要来源为技术进步,流域内农业规模化水平仍有较大提升空间;在空间关联格局上,效率的空间依赖性不固定,但空间聚集性总体增强;黄河流域农业生态效率呈现显著的空间收敛特征,且工业化水平、农业经济发展水平、农业机械化密度、财政支农力度、农业市场化程度会促进效率的空间收敛。

长江经济带养老服务均等化建设水平及收敛性研究

为准确把握长江经济带养老服务均等化建设现状,确保区域养老服务协调发展,构建养老服务均等化建设评价指标体系,以长江经济带11个省市最新面板数据为样本,运用熵值法、泰尔指数对长江经济带养老服务均等化建设水平进行测评,并基于σ收敛、绝对β收敛和条件β收敛模型实证检验其收敛效应。研究发现:样本考察期内,长江经济带养老服务均等化建设差距逐渐缩小,且区域间差异小于区域内差异。长江经济带上下游地区养老服务均等化建设水平存在显著的σ收敛特征,下游地区绝对β收敛程度最高,且在上述模型下,存在上下游地区对中游地区的“追赶”效应;不同驱动因素的条件β收敛情况各不相同:65岁以上的人口数量显著促进了长江经济带上下游地区养老服务均等化建设呈条件β收敛,卫生机构数量显著促进了中游地区呈条件β收敛,城乡居民基本养老保险基金支出显著促进了长江经济带整体及各地区养老服务均等化建设呈条件β收敛。实证分析结论为应对人口老龄化和提升养老服务均等化建设水平提供了重要政策启示。

黄河流域水生态文明建设水平的时空格局及空间收敛性

水生态文明建设是实现黄河流域生态保护和高质量发展的重要支撑。基于2010—2021年黄河流域地级市面板数据,采用时空极差熵值法、核密度估计法、探索性空间数据分析和空间面板模型对黄河流域水生态文明建设水平的时空格局及收敛性进行了实证分析。研究发现:黄河流域及上中下游城市水生态文明建设水平均呈现稳步提升态势,但水节约、水生态和水环境建设仍为主要短板;全流域及上中下游水生态文明建设水平的演进脉络各异,但极化趋势日益加剧;全流域水生态文明建设水平呈现显著的正向空间外溢效应和空间格局锁定特征,高高集聚区集中在下游城市,低低集聚区集中在上游城市;全流域及上中下游水生态文明建设水平均存在显著的绝对β收敛和条件β收敛,中游绝对β收敛最快,上游条件β收敛最快;人口密度、人力资本、经济发展水平、产业结构和城镇化水平对水生态文明建设水平的收敛性有显著影响,但存在明显的区域异质性。上述发现为协同推进黄河流域水生态文明建设提供了决策参考和经验证据。

黄河流域数字经济发展区域差异及动态演进

数字经济作为一种新经济形态,为社会经济发展带来了创新性的潜能和动力。黄河流域在发展中长期存在区域发展不平衡、产业结构不合理以及创新发展动力不足等问题,探讨和明晰数字经济对黄河流域区域发展的影响,对该区域高质量发展具有现实意义。本文以2011—2020年黄河流域73个地级及以上城市为研究对象,采用熵权法对各城市数字经济发展水平进行测度,在此基础上,采用Kernel密度估计法、Dagum基尼系数等方法对黄河流域数字经济发展的动态演进过程及其区域差异进行研究,并通过空间杜宾模型检验其收敛性。结果表明:在数字经济发展战略和行动的推动下黄河流域数字经济发展水平不断提高,且呈现下、中、上游梯度递减规律。黄河流域数字经济发展总体差异呈缩小的趋势,区域间差异是总体差异的主要来源。黄河流域整体以及上、中、下游地区均存在绝对β收敛和条件β收敛。

时空矢量场下人群活动聚散模式提取与分析

由于传统方法缺乏顾及人群在区域间的动态流动而无法反映人群在未来(下一时刻)的活动聚散趋势,因此,文中借助时空矢量场来建模人群活动的趋向性,通过矢量场理论中的散度算子来定量计算人群活动聚散强度,将人群活动聚散模式提取问题转化为时间序列聚类问题识别出主要聚散模式。在海口市滴滴出行数据集上进行实验,选取角度偏态系数证明了主体方向计算方法的有效性,提取出了4种主要人群活动聚散模式,并结合POI类型的分布情况对4种模式进行了语义解释,为探索人类移动性提供研究思路和方法支持。

关于黄河与河套古湖河湖关系演变的假说性分析——兼论对黄河内蒙古段生态治理的启示

黄河曾经在流经河套盆地过程中形成吉兰泰、乌兰布和、巴彦淖尔、呼包4个古湖,且在高湖面时期连成统一的“河套古大湖”,其后4湖分离并分别演绎了自己的河湖关系。在研习前人相关成果基础上,通过建立整体假说性解释框架,试图按照历史顺序与逻辑顺序统一的要求对该河段河湖关系的演变过程进行重建,并为与之相关的生态系统的治理提供借鉴。研究认为:主河道构建是黄河主动实施填湖、建堤、造槽并“甩湖”的过程与结果;冲积扇是黄河填湖的主要模式,而冲积扇顶附近凸起则是湖口淤塞、移动并最终筑成黄河自然堤的主要原因;巴彦木仁与磴口两地控制点对形成鄂尔多斯一侧黄河主河道起到了关键性作用;黄河西派在高湖面期间从巴彦木仁湖口注入吉兰泰-乌兰布和古湖,与从北面入湖的黄河水共同促成贺日木西尼古砂嘴及其延伸砂脊生长,并在低湖面期将这两个湖分离。基于对所述黄河历史过往的认识,须尽可能立足高效集成利用有限水资源这一观念,将减灾与适度重造沿河湖泊和绿洲结合,营建可持续的内蒙古段黄河生态体系。

黄河流域制造业高质量发展的空间格局演化、地区差异及收敛性分析

基于2010-2020年黄河流域73个地市面板数据,通过AHP-熵值法测算各地市制造业高质量发展水平,综合运用标准差椭圆、Dagum基尼系数及β收敛模型考察流域内制造业高质量发展的空间格局演化、地区差异及其空间收敛特征.研究结果表明:1)黄河流域制造业高质量发展水平呈波动上升趋势,但存在显著的空间非均衡性,始终保持“下强上弱”的空间分布格局.2)制造业高质量发展的重心向西南方向偏移,并表现为东西向集聚、南北向扩散趋势.3)制造业高质量发展的总体差异略有增加,组间差异是总体差异的主要来源.4)流域整体及上、下游地区支持条件β收敛和绝对β收敛机制,但不同地区的收敛速度和影响因素存在差异.基于实证结果,从提升黄河流域制造业高质量发展水平、缩小地区差距、促进区域差异化发展等方面提出建议.

北方主要河流水沙变异及其成因

为研究我国北方河流的水沙变异及主要成因,本文利用M-K检验法和水文量累积曲线法,分析了1950—2020年我国北方河流代表站径流量和输沙量的变化特征,探讨了影响北方河流水沙变化的主要因素。结果表明,淮河代表站年径流量没有明显的变化趋势,其他北方河流的年径流量具有减小或显著减小趋势;松花江代表站年输沙量无趋势变化,其他北方河流代表站年输沙量都有显著减少趋势;影响北方河流水沙变化的主要因素包括水土保持、水库拦沙、流域降水变化、引水引沙与泥沙综合利用、工程建设等,其中水土保持是北方河流流域保水减沙的主要措施,水库拦沙在江河水沙态势变异中发挥重要作用,流域降水变化也是北方河流水沙变异的影响因素,引水引沙与泥沙综合利用也对北方平原河流水沙变化发挥一定的作用。

珠江流域地域主体功能时空演化特征及驱动机制

为构建珠江流域高质量国土空间格局,推动上-中-下游协调发展。文章以主体功能区战略为切入视角,运用交叉转换矩阵和多尺度地理加权回归模型,对1990—2020年珠江流域“三区空间”演化特征与驱动机制进行分析。结果表明:1)近30年间珠江流域城镇空间剧烈扩张,生态空间微增,但农业空间大量减少,上-中-下游“三区空间”演化空间差异显著;全域农业空间面积大幅减少,主要在下游地区转换为城镇空间,在上、中游地区恢复为生态空间;2)不同主体功能区中,城市化地区城镇空间增长最为剧烈,生态功能区生态空间恢复显著,农产品主产区农业空间大量减少;3)珠江流域“三区空间”演化受社会经济要素、自然地理要素和道路交通要素的共同驱动,不同驱动因子对于不同类型空间演化的作用强度存在明显差异,其中,产业发展大幅推动了城镇空间的扩张,而生态环境保护政策有力地推动重点生态区地生态空间恢复。

“双碳”目标下黄河流域农业生态效率的动态演进与收敛特征

“双碳”目标下推进黄河流域农业生态效率提升,是推动实施黄河流域生态保护和高质量发展战略的重要途径。在农业减排固碳的发展要求下,以落实农业“双碳”目标为着力点,运用超效率SBM模型、Dagum基尼系数和收敛检验方法,测度2006-2021年黄河流域农业生态效率的时序演进、空间差异和收敛特征。结果表明:黄河流域农业生态效率整体呈波动上升趋势,但整体农业生态效率水平偏低,形成了“下游领跑、中游追赶、上游落后”的空间格局;黄河流域内农业生态效率差异逐渐扩大,差异主要源自超变密度,区域内差异由低到高依次为上游、下游和中游;黄河流域整体及上、中、下游的农业生态效率不存在σ收敛现象,但都存在显著的β绝对收敛和β条件收敛,种植业产值、机械化水平、农业产业集聚度、产业结构高级化水平等因素对β条件收敛的影响具有异质性。

长江干流沿江地区土壤重金属的分布、来源及潜在生态风险

为掌握长江干流沿江地区土壤重金属状况,开展土壤表层样品采集和重金属空间分布研究,使用PMF(positive matrix factorization)模型解析土壤重金属来源,并选取地累积和潜在生态风险等方法,评估重金属的污染状况和生态风险。结果表明:1)土壤重金属的积累程度不同,As、Cd和Cu的超标率高,污染明显。Cd和Cu的变异系数高于1.0,分布不匀,受某些污染源的影响显著。2)各重金属含量呈现条带状的空间格局,在多个地区出现高值,土壤环境质量受到人类活动的负面影响。3)土壤重金属积累主要来源于自然、工业排放、交通运输和农业生产,贡献率分别为36.65%、28.48%、20.07%和14.80%。其中Cd与工业活动有关,Pb和Zn来自交通排放,Cr和Ni与自然源密切相关,As和Cu来源于农业生产。4)Cd的污染程度最高,81.88%的点位达到轻度污染。40%以上的点位受到As、Cu、Ni和Pb污染。75%以上点位的Cr和Zn含量较低,污染程度不高。单项生态风险指数的均值从大到小依次为:Cd、As、Ni、Cu、Pb、Zn、Cr。综合生态风险指数均值为63.17,处于轻微风险水平。该研究作为土壤生态调查的核心,可为土壤环境管理和重金属污染修复提供科学依据。

黄河流域城市生态韧性时空分异及收敛研究——基于七大城市群61个城市的实证分析

科学测度黄河流域城市群城市生态韧性的发展现状及收敛趋势,对于黄河流域城市生态保护及高质量发展具有重要意义。选取2011—2020年黄河流域七大城市群61个地级市面板数据,以演化韧性为研究视角,从“抵抗-响应-创新”等维度,构建城市生态韧性评价指标体系,利用核密度估计和自然断裂法考察城市生态韧性的空间分异,借助不同类型收敛模型解析城市生态韧性的收敛趋势。研究表明:(1)黄河流域城市生态韧性总体均值为0.093,且呈缓慢发展趋势。(2)城市生态韧性表现为“下游城市群强、上中游城市群弱”的空间格局,城市群内部形成了“核心及省会城市—外围及边缘城市”递减的空间分布。(3)黄河流域和各城市群内部均存在绝对β收敛,其中晋中城市群收敛最快。加入控制变量后,黄河流域和各城市群内部呈现显著条件β收敛趋势,且收敛速度均有提升。此外,经济发展水平、人口密度等变量对城市生态韧性收敛的影响具有显著异质性。