Organic Phosphorus in Shallow Lake Sediments in Middle and Lower Reaches of the Yangtze River Area in China

Thirteen sediment core samples(0-10 cm) were taken from the seven lakes in the middle and lower reaches of the Yangtze River to determine the contents and distributions of organic phosphorus(P) fractions in the sediments of the shallow lakes in the area.The organic P fractions in the sediments were in the order of moderately labile organic P(MLOP) > moderately resistant organic P(MROP) > highly resistant organic P(HROP) > labile organic P(LOP),with average proportional ratios of 13.2:2.8:1.3:1.0.LOP,MLOP,and MROP were significantly related to the contents of total organic carbon(TOC),water-soluble P(WSP),algal-available P(AAP),NaHCO3-extractable P(Olsen-P),total P(TP),organic P(OP),and inorganic P(IP).However,HROP was significantly related to OP and weakly correlated with TOC,WSP,AAP,Olsen-P,TP or IP.This suggested that organic P,especially LOP and MLOP in sediments,deserved even greater attention than IP in regards to lake eutrophication.In terms of organic P,sediments were more hazardous than soils in lake eutrophication.Although OP concentrations were higher in moderately polluted sediment than those in heavily polluted sediment,LOP and MLOP were higher in the heavily polluted sediment,which indicated that heavily polluted sediment was more hazardous than moderately polluted sediment in lake eutrophication.

A Preliminary Study on the Rational Utilization of Land Resources in the Poverty-Stricken Mountainous Areas in the Upper Reaches of the Yangtze River:A Case Study of Xueshan Township

As one of the most fragile alpine plateau and canyon areas in China,the upper reaches of the Yangtze River are the key areas of ecological construction in China.It is also a key area for poverty alleviation in the country.Therefore,it is necessary to take into account the dual goals of poverty reduction and ecological environment construction,and explore a win-win road of ecological construction and poverty alleviation in line with the reality of the upper reaches of the Yangtze River.Taking Xueshan Township,Luquan Yi and Miao Autonomous County,Yunnan Province,which is located in the poor mountainous area of the upper reaches of the Yangtze River as an example,based on many field investigations and existing investigation and statistical data,this paper analyzes the current situation and main problems of land use in Xueshan Township,and then puts forward measures and suggestions for rational utilization of land resources in Xueshan Township.This can provide a necessary reference for the next implementation of rural revitalization strategy and ecological construction.

The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas

The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits.

Floristic Study of Vascular Plants in Typical Plant Communities in the Middle and Upper Reaches of the Yarlung Zangbo River

[Objective] Species composition and flora of vascular plants in the middle and upper reaches of the Yarlung Zangbo River were analyzed,to provide scientific basis for the estimation and protection of plant diversity,construction of ecological security shelter for the Tibetan Plateau.[Methods] In the middle and upper reaches of the Yarlung Zangbo River,quadrat (line transect) method was applied to investigate the phytocoenoses in sample plots,and relative literature was used to analyze the floristic composition and floristic element of vascular plants in the middle and upper reaches of the Yarlung Zangbo River.[Results]① There are 96 species (including subspecies and variations),69 genera of 35 vascular plant families,accounting for 16.83%,5.48%,1.66% and 11.63%,2.02%,0.31% of total vascular plant families,genera and species in Tibet and China.② There are 24 monotypic-genus families,accounting for 68.57% of the total family number in the local area;22 monotypic-species families,accounting for 62.86% of the total family number in the local area.Local flora shows the characteristics of ancient relict,such as Euphorbiaceae,Rubiaceae,Liliaceae and Ranunculaceae,they are all ancient primitive groups of the third flora and the fourth flora.③ Local vascular plant genera fall into 10 areal types and 8 variations.④ Temperate elements are much more than tropical elements,R/T is 0.19,indicating that vascular plants have typical temperate nature and residual tropical nature.There are only a few endemic genera,but more endemic species to the local area,and these species are closely related,of which there are some transitional species,indicating that local flora is too young to experience more differentiation and specialization.⑤ There are 24 Chinese endemic species,accounting for 25% of total number of species in the local area;among which there are 12 endemic species to Tibet,accounting for 50% of endemic species to China,12.5% of total number of species in the local area.Four key wild plant species are included in the second batch of national key protection.[Conclusions]① There are scarce plant groups in the local area.② Among the obvious advantages,single-genus (species) families possess the absolute advantage,and the flora has ancient origins.③ The local flora has diversified distribution types,and the complicated geographical elements.④ Temperate species possess obvious advantages,and the flora is young.⑤ Rich unique and rare species have high species diversity protection and research value.

Analysis on Landscape Pattern in the Upper and Middle Reaches of Yarlung Zangbo River:Taking Zhongba County,Angren County, Rikaze City as Example

Taking Zhongba County, Angren County, Rikaze City located at the Upper and Middle Reaches of Yarlung Zangbo River as landscape units , this paper studied the difference of the landscape pattern under various degrees of human disturbance in the three areas. The results showed that： the three areas all reflected the same characteristic of landscape pattern in Qinghai-Tibet Plateau, the natural landscapes were in the absolute dominant position. However, from Zhangba to Rikaze, with human disturbance intensity increasing, anthropogenic features of landscapes became more and more outstanding, In Zhongba, the landscape structure appeared to be simpler with coarse grains and a less rich diversity, Conversely, in Rikaze, the landscape showed a complicated shape with finer grains and a relatively richer diversity, This reflected that the impact of human activities to natural landscape behaved a gradually-growing trend from the upper reach to the middle one of Yarlung Zangbo River Basin.

Unsteadiness of COD in the Upper and Middle Reaches of Minjiang River

This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by the Water Quality Monitoring Station,Minjiang River Bridge,Leshan City,Sichuan Province.The results of the wavelet analysis indicate that the COD index oscillates alternatively and differently at each time-scale in an oneyear cycle,and the density of COD,subjected to the runoff volume,the effects of Wenchuan Earthquake and agricultural seeding and industrial construction,etc.,is high in winter and spring,mild in summer and autumn.

The SIA method for spatial analysis of precipitation in the upper-middle reaches of the Yangtze River

Using geographic information system (GIS) techniques and the newest seasonal and annual average precipitation data of 679 meteorological stations from 1971 to 2000, the multiple regressions equations of the precipitation and topographical variables are established to extract the effect of topography on the annual and seasonal precipitation in the upper-middle reaches of the Yangtze River. Then, this paper uses a successive interpolation approach (SIA), which combines GIS techniques with the multiple regressions, to improve the accuracy of the spatial interpolation of annual and seasonal rainfall. The results are very satisfactory in the case of seasonal rainfall, with the relative error of 6.86%, the absolute error of 13.07 mm, the average coefficient of variation of 0.070, and the correlation coefficient of 0.9675; in the case of annual precipitation, with the relative error of 7.34%, the absolute error of 72.1 mm, the average coefficient of variation of 0.092, and the correlation coefficient of 0.9605. The analyses of annual mean precipitation show that the SIA calculation of 3-5 steps considerably improves the interpolation accuracy, decreasing the absolute error from 211.0 mm to 62.4 mm, the relative error from 20.74% to 5.97%, the coefficient of variation from 0.2312 to 0.0761, and increasing the correlation coefficient from 0.5467 to 0.9619. The SIA iterative results after 50 steps identically converge to the observed precipitation.

Impact of vegetation restoration on hydrological processes in the middle reaches of the Yellow River,China

Sediment discharge from the Yellow River originates mainly from the drainage area between Hekouzhen and Longmen, i.e., the Helong area. Spatial-temporal variations of the vegetation cover in this area during the 1981-2007 period have been investigated using GIMMS and SPOT VGT NDVI data. We have also analyzed the interannual variations in vegetation cover and changes in annual runoff and sediment discharge, the consequences from precipitation change and the Grain for Green Project （GGP）. The results show that vegetation cover of the Helong area has increased during the 1981-2007 period. The northwestern part the Helong area, where the flat sandy lands are covered by grass, has experienced the largest increase. The region where the vegetation cover has declined is largely found in the southern and southeastern Helong area, which is a gullied hilly area or forested. Although precipitation was relatively low during the 1999-2007 period, the vegetation cover showed a significant increase in the Helong area, due to the implementation of the GGP. During this period, the most significant improvement in the vegetation cover occurred mainly in the gullied hilly areas of the Loess Plateau, such as the drainage basins of the Kuyehe and Tuweihe rivers and the middle and lower reaches of the Wudinghe and Yanhe rivers. A comparison of the average annual maximum NDVI between the earlier （1998-2002） stage and the next five years （2003-2007） of the GGP indicates that the areas with increases of 10% and 20% in NDVI account for 72.5% and 36.4% of the total area, respectively. Interannual variation of annual runoff and sediment discharge shows a declining trend, especially since the 1980s, when the decrease became very obvious. Compared with the 1950-1969 period, the average runoff during the 1980-2007 period was reduced by 34.8 × 10^8 m3 and the sediment discharge by 6.4 ×10^8 t, accounting for 49.4% and 64.9% of that in the 1950-1969 period, respectively. There is a positive correlation between the annual maximum NDVI and annual runoff and sediment discharge. This correlation was reversed since the implementation of the GGP in 1999 and vegetation cover in the He- long area has increased, associated with the decrease in runoff and sediment discharge. Less precipitation has been an important fac- tor driving the decrease in runoff and sediment discharge during 1999 2007. However, restoration and improvement of the vegetation cover may also have played a significant role in accelerating the decrease in annual runoff and sediment discharge by enhancing evapotranspiration and alleviating soil erosion.

Two series of copper-gold deposits in the middle and lower reaches of the Yangtze River area (MLYRA) and the hydrogen, oxygen, sulfur and lead isotopes of their ore-forming hydrothermal systems

Based on studies on the geological characteristics of the copper-gold deposits in the middle and lower reaches of the Yangtze River area (MLYRA) and their hydrogen, oxygen, sulfur and lead isotope compositions, it is concluded that there existed two series of copper-gold deposits. They are evolutional products of two ore-forming hydrothermal systems in different geodynamic settings and geological era. Series I is stratiform or stratabound copper-gold deposits. These deposits were formed by submarine exhalation and sedimentation of hydrothermal solutions in Her-cynian tensional tectonic environment after bot brine ascending along contemporaneous faults and exhaled into the sea-floor. Series II consists of copper-gold deposits related to medium and acidic magmatic intrusions. Their mineralizations took place in Yanshanian in a tensional or a transitional period to the tensional tectonic environment from the composite of the tethys tectonic regime and the Paleo-Pacific ocean tectonic regime, as well as in the upper mantle doming and crustal thinning environment. Copper-gold deposits were formed from the hydrothermal fluids, mixtures of magmatic water and part of meteoric water, by complex water-rock interactions and coupling dynamic processes of transport-chemical reactions. Superposition is an important condition for the formation of the large-scale copper-gold ore deposits.

Quantitative Classification and Ordination of Plant Communities in the Upper and Middle Reaches of the Yarlung Zangbo River Basin

Based on vegetation survey data and environmental data of the Yarlung Zangbo River Basin, we conducted a quantitative ecological analysis of the vegetation community composition and the relationship between species and the environment in the study area. The results showed that 44 sampling sites and 68 plant species in the study area can be classified into seven subtypes: Artemisia minor + Stipa purpurea;Artemisia demissa + Stipa purpurea + Artemisia wellbyi;Kobresia pygmaea;Trikeraia hookeri;Sophora moorcroftiana + Cotoneaster multiflorus + Pennisetum centrasiaticum;Artemisia frigida;Potentilla fruticosa + Orinus thoroldii. Detrended correspondence analysis(DCA) indicated that both longitude and altitude play important roles in site and species distribution patterns. In addition, canonical correspondence analysis(CCA) revealed that in the upper and middle reaches of the Yarlung Zangbo River Basin, changes in temperature and precipitation caused by longitude are the main factors controlling the formation and transition of vegetation community types. Moreover, natural vegetation could be divided into three types: desert steppe community(source area), alpine steppe community(middle reaches region), and shrub community(confluence of Yarlung Zangbo River and Nyangqu River).

Corridor effect of the spatial changes of landscape patterns in arid areas:A case study of the river corridor areas in the middle and lower reaches of Tarim River

在 Tarim Riverare 的中间、更低的活动范围的河走廊区域在 Ruoqiang 从 Qara 水库 inYuli 县沿着河节由传统的绿走廊统治了到泰泰马·莱克县，它在 Tarim 河分水岭在社会、经济的发展起一个重要作用与一极其重要的生态的功能。对水路垂直的缓冲区地区从水路在 5-kminterval 开始沿着两个河边被定义(10 km 更宽) 用缓冲区地区分析的方法。每个缓冲区地区的风景模式索引被计算，并且主要风景模式的索引被分析以便在风景和补丁层次上揭示放射的效果和河走廊的特征。放射的宽度通常是在学习区域的 30 km 的结果表演，和罐头直到在潜水艇的 50-70 km -- 区域 FG1 因为学习区域位于二排水盆，与在他们之间的一个生态的空隙的地区。树林和沼泽地的 Thelandscapes 通常在 10 km 缓冲区地区以内被散布(它意味着缓冲区地区是离开水路的 5 km；一样此后) 沿着两个河边。而且，缓冲区地区越靠近到水路，补丁密度和最大的补丁索引是越多 higher。在为学习区域的生态、环境的新生，河走廊的生态的效果的程度必须充分被考虑，并且工程必须科学地并且讲道理地被计划并且设计。

数字经济产业区域协同发展机理及路径研究--基于江西与粤港澳、长三角、长江中游城市群协同发展视角

数字经济产业区域协同发展对推动区域经济效率变革、质量变革和动力变革具有积极推动作用。近年来,江西充分发挥毗邻粤港澳大湾区、长三角以及位居长江中游城市群的地理优势,积极推动数字经济产业区域协同发展,打造了赣深电子信息产业集聚区、承接长三角数字产业转移示范区、赣湘电子信息产业园等,为江西数字经济产业高质量发展奠定了扎实基础,但是在数字经济产业区域协同发展过程中仍然存在协同规划缺乏、协同层次偏低、协同结构失衡、产业数字化滞后、数字技术协同创新弱和数据要素共建共享不畅等问题。这需从强化规划引领、提高协同层次、优化协同结构、加快数字化转型、推动数字技术协同创新和促进数据互联互通共用等方面加以破解。

长江中上游重要渔业水域环境质量评估

为准确评估长江中上游重要渔业水域水环境质量现状及变化趋势,提高水质评价效率,本研究基于11个水质参数,采用水质指数法(water quality index,WQI)对2006-2021年长江中上游三个重要渔业水域水质进行了综合评价,建立WQI min综合评价模型。结果显示:(1)长江中上游重要渔业水域的水温和高锰酸盐指数呈上升趋势;基于地表水环境质量标准(GB38338-2002),单因素水质评价结果表明监测水域内整体水质处于地表水Ⅴ类水标准,部分年份达劣Ⅴ类,主要污染指标为总氮。(2)通过综合评价方法分析,长江中上游重要渔业水域整体为“良”;2006~2021年长江中上游重要渔业水域水质质量呈逐年改善的趋势,且上游保护区的改善较大。(3)基于WQI方法,确定了长江中上游重要渔业水域的关键水质参数为:总氮、高锰酸盐指数、汞、溶解氧、氨氮、悬浮物以及水温,分别构建了上游保护区、中华鲟保护区以及四大家鱼保护区的WQI_(min)模型;考虑权重和不考虑权重的WQI min模型对比分析表明,考虑权重的WQI min模型的水质评价结果更加准确,该方法可有效评估长江中上游重要渔业水域的水质变化特征并可扩展用于其他水域。

1951—2020年黄河上中游径流变化特征及归因分析

【目的】河川径流是地表重要的水资源,对其变化特征和原因进行解析,是流域水资源科学管理规划的前提。【方法】本文采用Mann-Kendall趋势检验、Pettitt突变检验、Budyko弹性系数法等方法分析了黄河上游和中游近70年(1951—2020年)径流变化的趋势和成因。【结果】(1)1951—2020年黄河上游年降水量呈不显著增加趋势(4.04 mm/(10 a),P> 0.05),中游呈不显著减少趋势(4.90 mm/(10 a),P> 0.05);上游、中游年潜在蒸散发均呈不显著增加趋势(1.77、2.23 mm/(10 a),P> 0.05);(2)黄河上游和中游1980—2020年土地利用/覆盖变化明显,主要表现在林草面积的增加,上游、中游年NDVI分别以0.025/(10 a)、0.042/(10 a)的速率显著增加(P <0.01);(3)1951—2020年,上游和中游年径流量分别以3.46、7.46 mm/(10 a)的速率显著减少(P <0.01),并分别在1986年、1990年发生突变;(4)上游和中游径流对降水变化最为敏感,其次是土地利用/覆盖变化、潜在蒸散发变化,且径流对各影响因子的敏感性逐年增强,即气候和土地利用/覆盖的变化将更容易引起径流的变化;(5)土地利用/覆盖变化是导致黄河上游和中游径流减少的主要原因,其次是降水和潜在蒸散,但各影响因子对径流变化的影响性质和程度在上游和中游不同区间存在一定的差异。其中,上游地区降水、潜在蒸散发、土地利用/覆盖变化对径流的影响性质和程度分别为-14.04%、1.30%、112.73%;中游地区分别为21.54%、3.63%、74.83%。【结论】1951—2020年黄河上游和中游径流变化是气候变化和土地利用/覆盖变化共同作用的结果,但主要影响因素为人类活动主导的土地利用/覆盖变化,且各因子对径流的影响在不同区间存在一定的差异。本研究结果可为黄河上游和中游不同区间的水资源管理和综合治理提供理论支持。

长江中下游小麦新品系条锈病抗性评估与抗病基因分析

由小麦条锈菌(Puccinia striiformis West. f. sp.tritici Eriks.&Henn.)引起的条锈病是世界范围内小麦的重要病害。长江中下游麦区是中国小麦主产区之一和重要的小麦商品粮基地,也是中国小麦条锈病流行的重点防控地区。准确评价该地区小麦品种(系)对当前小麦条锈病流行小种的抗性,了解抗条锈基因在各个品种及所处麦区内的分布状况,对及时调整抗病育种目标、指导抗病品种及抗病基因的合理布局与应用具有重要意义。本研究收集了2019-2021年间苏、皖、鄂等长江中下游麦区103份小麦材料,包括34份当地主栽品种和69份参加新品种区域审定试验的高代品系,于2021年分别在陕西杨凌混合小种(CYR32、V26-lab)人工病圃及四川江油自然诱发病圃进行成株期抗条锈性鉴定;以当前流行条锈菌小种条中32(CYR32)和G22致病类群(V26-lab)对参鉴品系进行苗期分小种鉴定,利用16个已知抗条锈基因的19个SNP标记进行分子检测,其中包括11个全生育期抗病基因[Yr5a、Yr5b (YrSP)、Yr6、Yr7、Yr9、Yr15、Yr26、Yr28、Yr81、YrZH84和YrAS1676]和5个成株期抗病基因(Yr18、Yr30、Yr78、Yr86和YrLT26),推测小麦品系可能携带的抗病基因。结果表明,34份主栽品种中,23份表现成株期抗病。在69份高代品系中,苗期对CYR32和V26-lab小种表现抗病的品系分别有11份和13份,对CYR32和V26-lab均表现免疫或者近免疫的品系仅有2份。根据品系成株期抗病DS值的聚类热图结果表明,在杨凌表现抗病的品系有44份,在江油表现抗病的品系有25份,在两地均表现环境稳定抗病的品系有17份。分子检测表明,参鉴品系中可能携带Yr5b、Yr6、Yr7、Yr9、Yr30、Yr78、Yr81、Yr86、YrZH84、YrLT26和YrAS1676,其中只有Yr6、Yr81和YrLT26显著影响抗病性,没有发现可能携带Yr5a、Yr15、Yr18、Yr26和Yr28的品系。此外,Yr78、Yr81、Yr86和YrAS1676组合表现可有效抗条锈病。长江中下游麦区小麦品系对小麦条锈菌当前流行小种的抗性整体水平较2010年前明显提高,抗病基因的使用呈多样化趋势。

黄河中上游区土地使用结构与布局复合优化

黄河中上游地区生态环境脆弱,空间发展问题突出,探索该区域土地使用结构和布局优化配置是实现黄河流域生态保护和高质量发展的有效途径。该研究以黄河中上游地区为研究对象,基于该区域土地使用、社会经济等数据,运用多目标规划(multi-objective programming,MOP)和PLUS模型模拟了惯性发展、生态保护、经济优先和生态-经济均衡4种情景下研究区未来土地格局和变化趋势,并在平衡生态与经济的目标下提出最优土地使用结构和布局方案。结果表明:1)4种情景下,土地使用比例结构存在较大差异;2)均衡情景下的区域土地使用结构和空间布局方案为最优,其综合效益值最高且达到19481.00亿元,与生态保护情景相比其经济效益(12223.88亿元)增长了4.07%,与经济优先情景相比其生态价值(7257.12亿元)增长了2.32%;经济优先情景下综合效益值为20273.96亿元,是4种情景下最高的。研究可为黄河中上游区域未来土地使用规划编制和土地可持续利用规划提供依据。

考虑径流过程矢量化的机器学习洪水预报模型

准确的超前洪水预报有利于开展防洪减灾工作和优化水资源调度。本文提出一种针对场次洪水的径流过程矢量化方法(Runoff Process Vectorization, RPV),并耦合3种机器学习(Machine Learning, ML)模型构建了RPV-ML洪水预报系列模型。以黄河中上游孤山川、佳芦河和祖厉河3个典型流域为研究区,分别基于43、28、37场洪水的降雨径流数据,按照洪水场次7∶3的比例进行模型训练和验证。研究表明:(1)相同预见期条件下RPV-ML模型在孤山川、佳芦河和祖厉河流域洪水预报纳什效率系数更高、均方根误差和洪峰相对误差更低,RPV-ML模型比ML模型具有更好的预报性能,在预见期为4~6 h时优势更显著;(2) RPV-ML和ML模型预报精度会随着预见期增加逐渐下降,但RPV-ML预报精度呈现缓慢下降趋势,具有更好的鲁棒性;(3)基于RPV改进的时间卷积网络(Temporal Convolutional Network, TCN)可以更好地克服预报误差问题,RPV-TCN模型在3个流域预报性能最好。

晚清长江中上游民船运输状况——以《长江三峡及重庆游记》为中心的考察

1883年英国商人立德乐通过实勘实测的方法记录了其在长江中上游流域乘坐民船的航行情况,并留下数万字的旅行记录——《长江三峡及重庆游记》,生动再现了晚清我国长江中上游流域传统民船的运输状况。通过对行记的考察可以厘清我国民船的运输情形,自从清代前期长江流域全面贯通以来,逐渐积累了成熟的造船技术、完善的民船运营结构、丰富的行船经验等,都促进了长江民船运输专业化,高效率水运系统的形成。与近代轮船运输相比,传统民船在运输价格、航行范围、运营的灵活性上都具有优势,即使在晚清长江中上游开通轮船运输后,民船运输仍在持续发展。

基于文献计量分析的长江中上游鱼类资源研究综述

针对长江中上游鱼类资源领域研究,以主题“长江上游”“长江中游”“金沙江下游”“鱼类资源”“鱼类早期资源”为检索条件,筛选了2023年7月前中国知网及Web of Science核心合集数据库收录的503篇文献,利用CiteSpace进行文献计量分析并绘制科学知识图谱,在此基础上从文献数量分布、研究机构及代表作者分布、研究主题内容、研究热点及演变趋势方面对长江中上游鱼类资源领域研究进行了综述。结果表明:中国科学院和中国水产科学研究院等是该领域的领军机构;从发展趋势上看,该领域已形成了鱼类资源现状及变化趋势、鱼类资源的影响机制以及鱼类资源的保护对策3个重要的研究热点和方向。后面需进一步完善江段鱼类资源的长期动态监测方法、梯级开发背景下鱼类资源的变动情况以及鱼类资源的协同保护方法等方面的研究。

大渡河上游某河段鱼类栖息地适宜性评价

以大渡河上游某水电站坝下13 km大渡河干流河段和坝下支流入大渡河汇合口以上4 km支流河段鱼类栖息地为研究河段,从鱼类有效栖息地面积计算、支流河底连通性模拟两方面开展栖息地适宜性评价,重点分析评价了产卵期齐口裂腹鱼和重口裂腹鱼两种目标鱼类对流速与水深的适宜性指标,得到了研究河段鱼类栖息地适宜性指数和等级:坝下干流鱼类栖息地适宜性指数为0.68,适宜性等级为适宜;支流河口以上4 km河段鱼类栖息地适宜性指数为0.58,适宜性等级为一般适宜评价。