基于生态-景观视角的城镇河岸带风貌特征评价——以晋江市河溪为例

基于生态与景观双视角初步构建了河岸带风貌(RV,riparian view)综合评价指标体系,选取全域型城镇化典型代表地区晋江市12条主要河溪的120个河段进行数据取样与河岸带风貌综合评价值的计算,以此分析了晋江河溪河岸带风貌的现状,并从整体最优与各项影响因子最优两个层面探讨了河岸带风貌的指标优化控制值,结果表明:(1)受城镇化影响晋江目前河溪河岸带风貌整体情况并不乐观,目前已不存在状态非常好的河段,且96.67%河溪的河岸带风貌已经处于消失、丧失、破坏的状态,3.33%河溪的河岸带风貌也受到了消极的影响;(2)滩涂特征与岸线特征处于非常差状态的河段比例分别达到了57.5%与29.17%,植被特征无明显的非常好与非常差的极端状态,基本集中在36.67%较差、50%一般、13.33%较好的状态,而水体特征(除水质)总体相对较好的河段数量比例为56.67%;(3)浅滩保有率、滩涂宽度、自然滩涂保有度、滨河土地硬度、河道硬度、视线阻隔、植被带高度因子评分值为0的比例分别达到了89.17%、50.83%、64.17%、40.83%、52.50%、63.33%、51.67%,均高于其他评分值比例,这些因子的状态以非常差为主,是目前晋江河溪河岸带风貌短板;(4)从整体最优化与各项因子最优化两个角度提出20项指标优化控制值,若实现这些目标值,RV综合评价的得分值将由原有的1.59分别提升至1.96和3.85,晋江河溪河岸带风貌能够从较差的现状提高到一般或非常好的水平。     

三峡库区河流生境质量评价

三峡水库建成蓄水后,库区流水生境的大幅度减少及垂直落差最高可达30 m的消落带的形成,使库区支流生境发生了剧烈变化,因此对库区河流生境质量评价十分必要。基于水文情势、河流形态和河岸带生境3个方面18个指标的河流生境评价指标体系,对三峡库区36条重要支流254个样点河段进行河流生境质量评价。结果表明,4.72%的样点河流生境质量处于优等,30.31%为良好等级,49.61%为一般等级,15.35%为较差等级,没有最差等级的样点。对于表征河流生境状况的水文情势、河流形态和河岸带生境3个类别,254个河段总体上河岸带生境状况最好,其次为水文情势,河流形态最差。从总体上来看,三峡库区支流生境质量是自然环境和人类活动相互作用的结果,其中河岸带植被状况、消落带宽度、人为干扰、河床底质状况、水文情势自然性等为主要的驱动因子。     

三峡库区河流生境质量评价

三峡水库建成蓄水后,库区流水生境的大幅度减少及垂直落差最高可达30 m的消落带的形成,使库区支流生境发生了剧烈变化,因此对库区河流生境质量评价十分必要。基于水文情势、河流形态和河岸带生境3个方面18个指标的河流生境评价指标体系,对三峡库区36条重要支流254个样点河段进行河流生境质量评价。结果表明,4.72%的样点河流生境质量处于优等,30.31%为良好等级,49.61%为一般等级,15.35%为较差等级,没有最差等级的样点。对于表征河流生境状况的水文情势、河流形态和河岸带生境3个类别,254个河段总体上河岸带生境状况最好,其次为水文情势,河流形态最差。从总体上来看,三峡库区支流生境质量是自然环境和人类活动相互作用的结果,其中河岸带植被状况、消落带宽度、人为干扰、河床底质状况、水文情势自然性等为主要的驱动因子。     

大汶河水生态环境健康状况与土地利用的相关性

为了解大汶河水生态环境现状及河岸带土地利用类型对其影响,基于2017年4月大汶河流域水生态调查数据,采用主成分分析和相关分析方法对流域地形、水文、水环境因子、主要水生生物因子和栖息地质量5个方面共19个候选指标进行筛选和优化,构建了大汶河生态系统健康评价多指标体系并用于大汶河水生态健康评价。结果表明:水环境因子和水生生物类型指标在健康评价指标体系中所占权重较大;大汶河水生态系统健康状况评价结果主要以一般和较差为主,分别占总采样点的58.33%和20.83%,仅瀛汶河上段、大汶河南支上段和大汶河干流下段部分断面处于健康或亚健康水平;城镇村及工矿用地、耕地和交通用地与大汶河生态健康综合指数呈负相关,是该流域水生态系统受到破坏的主要因素。     

大汶河水生态环境健康状况与土地利用的相关性

为了解大汶河水生态环境现状及河岸带土地利用类型对其影响,基于2017年4月大汶河流域水生态调查数据,采用主成分分析和相关分析方法对流域地形、水文、水环境因子、主要水生生物因子和栖息地质量5个方面共19个候选指标进行筛选和优化,构建了大汶河生态系统健康评价多指标体系并用于大汶河水生态健康评价。结果表明:水环境因子和水生生物类型指标在健康评价指标体系中所占权重较大;大汶河水生态系统健康状况评价结果主要以一般和较差为主,分别占总采样点的58.33%和20.83%,仅瀛汶河上段、大汶河南支上段和大汶河干流下段部分断面处于健康或亚健康水平;城镇村及工矿用地、耕地和交通用地与大汶河生态健康综合指数呈负相关,是该流域水生态系统受到破坏的主要因素。     

图们江流域河流生态系统健康评价

河流是重要的自然生态系统,也是重要的生态廊道之一,图们江流域河流生态系统的健康状况,对维护跨国界流域的水环境的管理和可持续发展有着重要的意义。基于河流水文、河流形态、河岸带状况、水体理化参数以及河流生物5个层面选取22个指标构建了图们江流域河流生态系统健康评价指标体系,运用层次分析法和加权平均法对其进行了健康评价。评价结果表明,虽然该地区处于"健康"级别,但也有28%的地区处于"亚健康"状态。河流健康综合指数(RHI`)与河流生物指标、水体理化指标、河流形态指标、河岸带指标等4项呈显著相关(P0.05),相关系数依次为0.847、0,757、0.740、0.547。研究结果表明图们江流域水生生物的生存环境遭到严重破坏、水体污染严重,河岸带生态退化、城市化影响严重等一系列影响河流健康的问题。     

基于B-IBI指数的温榆河生态健康评价

基于温榆河底栖动物和水质采样数据,采用底栖动物完整性指数(B-IBI)方法,进行温榆河生态健康评价,并探求河流水质与B-IBI指数的相关性。通过分布范围、判别能力以及相关性分析等,确定研究区B-IBI指标体系,包括总分类单元数、总生物量、优势分类单元个体相对丰度、敏感类群分类单元数、生物指数和粘附者个体丰度6个指标。根据参照点25%分位数确定温榆河底栖动物完整性评价标准,即B-IBI>1.821为健康,1.366—1.821为亚健康,0.910—1.366为一般,0.455—0.910为较差,0—0.455为极差。结果表明,温榆河27.3%河段处于健康状态,9.1%河段处于亚健康状态,13.6%河段处于一般状态,50%河段处于较差和极差状态。河流水质与B-IBI指数的相关系数为-0.549,表明生物指标作为水体评价的补充指标十分必要。     

太湖流域宜兴片河流生境质量评价

建立包含河道生境、河岸生境和滨岸带生境3方面共10项的河流生境质量评价指标体系,对太湖流域宜兴片42个样点进行生境评价及空间差异比较,分析不同土地利用类型下河流生境各参数的差异性,探讨河流生境质量指数与富营养化综合指数的相关关系。结果表明:河流生境质量指数分值介于29～79,31.0%样点生境质量处于较差和很差等级,57.1%样点为一般等级,表明整体上生境退化明显;南部丘陵山区河流的生境质量状况好于广大的平原河网区;不同土地利用类型下河流生境质量差异显著,林地区域的生境质量明显好于耕地和建设用地;河流生境质量指数与富营养化综合指数显著负相关,说明水质状况对河流生境质量具有较大贡献。     

城镇化背景下河流生境评价——以深圳市为例

城镇化背景下,河流生态系统退化趋势明显,有效评价河流生境状况是修复和保护河流生态系统健康的重要基础。深圳市作为全国经济发展的窗口城市,河流生境的调查研究十分匮乏。因此,为阐明深圳市不同城镇化程度的流域河流生境的差异与主要影响因素,对深圳市两个代表性流域的河流生境展开了研究。针对深圳市河流的生境特点,于2019年丰水期（8月）和枯水期（11月）对城镇化程度较高的深圳河流域的13个样点和城镇化程度较低的坪山河流域12个样点河段的生境状况进行定量调查与评价。采用综合评价法,从河床、河道和河岸带3个方面选取10个生境指标,构建深圳市河流生境评价指标体系和评价方法。结果表明：深圳河流域河流生境质量总体较差,生境评价等级为"良"、"中"、"差"的样点河段分别占7.7%、38.5%、53.8%;坪山河流域河流生境质量总体较好,生境评价等级为"优"、"良"、"中"、"差"的样点河段分别占8.3%、41.7%、41.7%、8.3%。方差分析结果表明两次调查河流生境状况无显著性差异,短时间跨度内河流生境状况变化较小;两个流域河流生境状况差异显著,城镇化程度较低的坪山河流域河流生境质量显著好于城镇化程度较高的深圳河流域。河流生境评估指标主成分分析结果表明人类活动强度、河岸稳定性、河道变化、底质、河岸土地利用及植被多样性是影响深圳市河流生境变化的主要因子。本文对河床、河道、河岸带3个方面分别提出针对性的修复建议,对深圳市河流的生境修复和保护具有重要的指导作用。     

辽河干流河流化学完整性评价方法对比研究

基于河流水环境和河岸带生境状况进行河流化学完整性评价,可以全面综合的判断河流水体及河岸带化学污染情况,对有效控制水体污染,科学制定整治计划,恢复河流自身的环境承载力及生态系统功能以及对河流生态系统的修复都具有重要意义。以辽河干流为研究对象,探讨了化学完整性的概念、评价指标、评价标准及评价方法,从河流水环境和河岸栖息地环境两方面选取了19个指标,构建了河流化学完整性评价指标体系。同时采用模糊综合评价法、贴近度法和综合指数法分别对辽河干流化学完整性进行评价,最终筛选并确定综合指数法更适合河流化学完整性评价。综合指数法评价结果表明,辽河干流化学完整性评价结果总体表现为“一般”,河流水环境总体评价为“一般”,哈大高铁、达牛和盘山闸评价为“差”。其中哈大高铁和达牛地处交通节点,受人为干扰较大。另外盘山闸长期处于施工状态且靠近市区,施工废料与城市污水污染不断。评价结果为研究者及管理者开展辽河干流生态修复与后评估等工作提供指标与方法参考。     

河岸无脊椎动物多样性维持机制研究进展

河岸是河流与陆地之间重要的生态界面,生物多样性丰富,但受到人为活动的严重威胁。无脊椎动物在河岸生物多样性中占有重要地位,发挥着非常重要的生态功能,也是水生生态系统和陆地生态系统之间物质和能量联系的重要纽带。尽管已有很多学者对河岸无脊椎动物群落进行了研究,但缺乏对河岸无脊椎动物多样性维持机制的总结。本文结合洪水和干旱、营养物质、微生境多样性、河岸植被、微气候梯度、食物资源以及河流空间梯度等影响因素,初步讨论和归纳了河岸无脊椎动物多样性的维持机制。周期性洪水和干旱引发了无脊椎动物的繁殖和迁移等行为,增加了河岸无脊椎动物群落周转率,为无脊椎动物创造了理想的条件。充足的营养物质使河岸具有较高的初级生产力,支撑了较高的无脊椎动物多样性。较高的微生境多样性为无脊椎动物提供了多样的生态位空间,孕育了特殊的河岸无脊椎动物种类。复杂的河岸植物群落不但是河岸无脊椎动物的食物来源之一,也为河岸无脊椎动物提供了多样的生态位空间和重要的避难场所。微气候环境的空间分异提供了复杂多样的生境条件,为水生无脊椎动物和陆生无脊椎动物种类在河岸共存创造了条件。跨越界面的资源补给增加了河岸无脊椎动物的食物可利用率,为河岸无脊椎动物提供了特殊的食物来源。这些因素在空间上呈现出明显的纵向梯度和侧向梯度,从更大尺度上为河岸无脊椎动物的多样化提供了条件。因此,探讨河岸无脊椎动物多样性的维持机制对于河岸生物多样性保护以及河流生态系统综合管理具有重要的指导意义。     

河岸带生态系统退化机制及其恢复研究进展

恢复和重建自然和人为干扰导致的退化河岸带生态系统是目前恢复生态学、流域生态学等学科研究的重要内容之一．对河岸带生态系统的干扰表现在河流水文特征改变、河岸带直接干扰和流域尺度干扰3个方面,分别具有不同的影响机制．河流水文特征改变通过改变河岸土壤湿度、氧化还原电位、生物生存环境以及沉积物传输规律对河岸带生态系统产生影响;河岸带直接干扰通过人类活动及外来物种入侵而直接影响河岸带植被多样性;流域尺度干扰则主要表现在河道刷深、河道淤积、河岸带地下水位降低和河流冲刷过程改变等．河岸带生态恢复评价对象包括河岸带生态系统各要素,评价指标已从单一的生态指标转向综合性指标．河岸带生态恢复应在景观或者流域尺度上进行考虑,识别对其影响的生物和物理过程以及导致其退化的干扰因子,通过植被重建与水文调控来进行．扩展研究尺度和研究对象及采用多学科的研究方法将是今后相关研究中的重要问题．     

Development of a reference-based method for identifying and scoring indicators of condition for coastal plain riparian reaches

Indicators of riparian ecosystem condition for headwater coastal plain streams were identified from data obtained from a reference population of reaches ranging widely in ecological condition. Each indicator was associated with some facet of hydrologic, biogeochemical, and/or habitat functioning and to channel condition, riparian zone condition, or both. Variation in the condition of the indicators among reference reaches provided a framework for developing narratives that could be used to partition and score the condition of the indicators from 0 (severely altered) to 100 (relatively unaltered). The developed narratives were the basis for creating a scoring approach for assessing stream condition at the reach scale (100-m long × 60-m wide segment). This approach was designed to be a rapid, field-based assessment method (<1 h/site) that could be applied by resource professionals with several days of training in the method. Although most alterations to riparian reaches usually affect both channels and riparian zones together, the ability to score channel and riparian zone condition separately is useful for diagnosing problems and suggesting viable restoration options at the reach scale. The assessment method is also useful for comparing the condition of reaches relative to one another, thus offering guidance for prioritizing restoration efforts at a watershed scale.     

LiDAR derived ecological integrity indicators for riparian zones: Application to the Houille river in Southern Belgium/Northern France

Riparian zones are central landscape features providing several ecosystem services and are exceptionally rich in biodiversity. Despite their relatively low area coverage, riparian zones consequently represent a major concern for land and water resource managers confirmed within several European directives. These directives involve effective multi-scale monitoring to assess their conditions and their ability to carry out their functions. The objective of this research was to develop automated tools to provide from a single aerial LiDAR dataset new mapping tools and keystone riparian zone attributes assessing the ecological integrity of the riparian zone at a network scale (24 km).Different metrics were extracted from the original LiDAR point cloud, notably the Digital Terrain Model and Canopy Height Model rasters, allowing the extraction of riparian zones attributes such as the wetted channel (0.89 m; mean residual) and floodplain extents (6.02 m; mean residual). Different riparian forest characteristics were directly extracted from these layers (patch extent, overhanging character, longitudinal continuity, relative water level, mean and relative standard deviation of tree height). Within the riparian forest, the coniferous stands were distinguished from deciduous and isolated trees, with high accuracy (87.3%, Kappa index).Going further the mapping of the indicators, our study proposed an original approach to study the riparian zone attributes within different buffer width, from local scale (50 m long channel axis reach) to a network scale (ca. 2 km long reaches), using a disaggregation/re-agraggation process. This novel approach, combined to graphical presentations of the results allow natural resource managers to visualise the variation of upstream–downstream attributes and to identify priority action areas.In the case study, results showed a general decrease of the riparian forests when the river crosses built-up areas. They also highlighted the lower flooding frequency of riparian forest patches in habitats areas.Those results showed that LiDAR data can be used to extract indicators of ecological integrity of riparian zones in temperate climate zone. They will enable the assessment of the ecological integrity of riparian zones to be undertaken at the regional scale (13,000 km, completely covered by an aerial LIDAR survey in 2014).     

Importance of scalar and riparian habitat effects for assessment of ecological status using littoral diatoms

The classification of waterbodies under the Water Framework Directive is dependent on the ability of monitoring programmes to reflect habitat quality using biotic elements including benthic diatom communities. This study investigated the influence of specific riparian habitats, of mixed woodland, grassland and lake artificial structures such as jetties and slipways, on benthic diatom assemblages in nine lakes across gradients of total phosphorus, alkalinity and in the presence or absence of Dreissena polymorpha. The heterogeneity of the benthic diatom assemblages at riparian and lake scale was assessed by taking three replicates per site category per lake, following standard European Union protocols. Canonical correspondence analysis (CCA) and mixed effect modelling was used to investigate the main environmental controls on assemblage structure. Non-metric Multidimensional Scaling (NMDS) was used to examine patterns in assemblage structure. No single environmental gradient was found to control benthic diatom composition, with differences among assemblages influenced both by riparian habitat type within lakes and interaction of multiple environment gradients, including presence of D. polymorpha. Greater control was exerted on community structure at the lake than local riparian scale. The influence of scalar factors on diatom assemblages increased with increasing scale. We recommend that for effective monitoring and assessment of ecological status, standard sampling protocols should include localised littoral habitats with individual samples pooled across riparian habitat types, thereby accounting for both multiple environmental and spatial controls on community structure.     

Applicability of macrobenthos indexes in health assessment upstream of a large river: A case study in the Babian River of the Red River Basin,China

Biological assessment is an important component of river health assessments. With the thorough growth of river health assessment in China, the scientific verification and screening of straightforward, easily quantifiable, and widely used bio-assessment indexes has emerged as a significant scientific challenge that needs to be resolved immediately in river health assessment. In 2019, 28 sections of the Babian River were examined for water quality, macrobenthos, status of the riparian zone and societal value. Based on the presence of macrobenthos in river health assessments, the applicability of 17 indexes was analyzed. The indexes that could differentiate between reference sites and impaired sites were B-IBI, S₂, S₃, and BMWP, which had good correlation with environmental factors. Although there was no significant link with riparian conditions, B-IBI, S₂, S₃, and BMWP had strong negative correlations with total ammoniacal nitrogen, total nitrogen, and total phosphorus but S₂, S₃, and BMWP are effective alternatives for B-IBI in river health assessment since their results were comparable to those of B-IBI, which covered all the assessment grades. Moreover, when constructing and selecting a bio-assessment index, more attention should be paid to the role of dominant and rare species, as well as the appropriate condition of indexes. In addition, riparian condition is a necessary aspect of river health assessment, but it is challenging to reflect the influence of land components on river health because of the small scale of riparian investigation. Therefore, it is necessary to introduce basin-scale indexes to optimize river health assessment systems. By doing this, watershed system management and overall governance will be supported more effectively.     

九龙江源头山地河流河岸带植物区系研究

在野外调查、标本采集和综合分析国内有关山地河流河岸带植被研究的基础上,探讨山地河流河岸带植物区系特征。调查表明：九龙江源头山地河流共有维管植物145科390属574种,其中蕨类植物29科54属80种,裸子植物6科8属10种,被子植物110科328属484种。综合分析表明,山地河流（以九龙江源头河段为例）河岸带植被具有如下典型特征：（1）植物区系组成丰富,优势科、属明显,单型属、单种属和少种属,单种科、少种科比例大;（2）植物区系起源古老,珍稀、孑遗植物众多;（3）区系地理成分复杂,联系广泛,能充分反映区域气候、地形地貌和人为活动等自然和人为干扰条件。表明山地河流河岸带在区域生物多样性保护中具有极其重要的价值。     

Assessing Riparian Quality Using Two Complementary Sets of Bioindicators

Biological indicators are being increasingly used to rapidly monitor changing river quality. Among these bioindicators are macroinvertebrates. A short-coming of macroinvertebrate rapid assessments is that they use higher taxa, and therefore lack taxonomic resolution and species-specific responses. One subset of invertebrate taxa is the Odonata, which as adults, are sensitive indicators of both riparian and river conditions. Yet adult Odonata are not necessarily an umbrella taxon for all other taxa. Therefore, we investigated whether the two metrics of aquatic macroinvertebrate higher taxa and adult odonate species might complement each other, and whether together they provide better clarity on river health and integrity than one subset alone. Results indicated that both metrics provide a similar portrait of large-scale, overall river conditions. At the smaller spatial scale of parts of rivers, Odonata were highly sensitive to riparian vegetation, and much more so than macroinvertebrate higher taxa. Odonate species were more sensitive to vegetation structure than they were to vegetation composition. Landscape context is also important, with the odonate assemblages at point localities being affected by the neighbouring dominant habitat type. Overall, benthic macroinvertebrates and adult Odonata species provide a highly complementary pair of metrics which together provide large spatial scale (river system) and small spatial scale (point localities) information on the impact of stressors such as riparian invasive alien trees. As adult Odonata are easy to sample and are sensitive to disturbance at both small and large spatial scales, they are valuable indicators for rapid assessment of river condition and riparian quality.