Examining Rate of Built-Up Areas on the Vegetation Cover along River Riara Riparian within Kiambu Town, Kenya

Urban river riparian spaces and their natural systems are valuable to urban dwellers;but are increasingly affected and ruined by human activities and in particular, urbanization processes. In this research, land sat and sentinel satellite imagery apt for change detection in vegetation cover, both landsat and sentinel imagery, covering the period between 1970 and 2021 in epochs of 1973, 1984, 1993, 2003, 2015 and 2021 years were used to establish the correlation between vegetation cover and built-up area along River Riara river reserve. The images were analysed to extract the built-up areas along the river reserve, including the buildings, and the rate of human settlements, which influenced vegetation cover. Normalized Difference Built-Up Index (NDBI) and Normalized Difference Vegetation Index (NDVI) were computed using the Short-Wave Infrared (SWIR) and the Near Infra-Red (NIR) bands to show the rate of change over the years. Results indicate NDVI values were high, compared to NDBI values along river Riara in the years 1973 and 1993 implying that there was more vegetation cover then. However, in the year 2021, the NDVI indicated the highest value at 0.88, with the complementary NDBI indicating the highest NDBI value at 0.47. This represents a significant increase in built-up areas since 2015 more than in previous epochs. Either, there was a significant increase in NDBI values, from 0.24 in 1993 to 0.47 in 2021. More so, the R-squared value at 0.80 informed 80% relationship between NDBI and NDVI values indicating a negative correlation.

平原沙土区河岸带不同植被类型对土壤团聚体稳定性的影响

[目的]明晰不同植被类型对土壤团聚体稳定性及团聚体有机碳含量的影响,为平原沙土区河岸带土壤团聚体稳定性和抗蚀能力提升提供基础数据。[方法]以江苏省平原沙土区丰县复新河河岸带15年生杨树纯林、柳树纯林、杨柳混交林3种植被类型及对照为对象,用湿筛法对0—20 cm, 20—40 cm, 40—60 cm^(3)个层次土壤颗粒进行物理分级,测定了>0.25 mm团聚体含量(R0.25)、平均重量直径(MWD)、几何平均直径(GMD)、分形维数(D)及有机碳等主要指标,并利用线性回归对各指标相关性进行分析。[结果](1)试验地各土层团聚体以<0.25 mm微团聚体为主,占总团聚体含量的50.33%~80.00%。3种植被类型>2 mm和0.25~2 mm粒径团聚体含量高于对照,各土层中杨树纯林>2 mm大团聚体含量最高。(2)与对照相比,3种植被类型R0.25,MWD和GMD分别提高了41.77%~91.28%,29.89%~79.08%和37.60%~94.32%,其中杨树纯林效果最好。杨树纯林和柳树纯林D显著低于对照(p<0.05)。(3)试验地土壤团聚体有机碳含量范围为1.51~6.48 g/kg。与对照相比,3种植被类型下土壤团聚体有机碳含量提高了31.67%~71.68%,杨树纯林团聚体有机碳含量显著高于柳树纯林和杨柳混交林(p<0.05)。杨树纯林在0—20 cm土层各粒径团聚体有机碳含量最高。(4)线性回归分析表明土壤团聚体稳定性与有机碳显著相关,尤其是与大团聚体有机碳含量显著相关。此外,细根生物量、全氮含量、碳氮比和含水率也是影响团聚体稳定性的重要因素。[结论]平原沙土区河岸带杨树纯林更有利于提高土壤团聚体稳定性,增加土壤抗蚀能力。

人类活动对河岸湿地植物群落的影响

人类活动干扰是河岸带外来植物侵入的主要原因之一.选取唐河县乡村段和城市段,对比研究河岸湿地外来植物群落特征,旨在探明不同类型人类活动对外来植物的影响程度.研究发现,6个处理中乡村段河岸上乡土植物的比例最高(65.38%).乡村段的乡土植物比城市段多,乡村段的入侵植物明显低于城市段.无论是乡村段还是城市段,乡土植物优势度都最高,乡村段河岸的乡土植物优势度高于城市段,而乡村段河岸外来植物的优势度明显低于城市段,乡村段河岸的入侵植物优势度也显著高于城市段.在乡村段的外来植物中,多年生旱生草本植物的比例最高(38.29%),而在城市段的外来植物中,一年生中生草本植物的比例最高(29.45%).乡村段与城市段的本土植物相似度最高(0.823),其次是乡村段与城市段的外来植物(0.692).随着人类活动干扰强度不断增加,物种的更替变化导致不同区域的植物群落构成呈现出很大的差异,降低了区域之间植物物种的相似性.唐河县段河岸带外来植物种类的构成特点,反映出人类活动对河岸带外来植物干扰逐渐扩大的趋势,包括快速城市化和农业活动等.

Hydraulic Properties of Rocky Mountain First-Order Alluvial Systems and Diurnal Water-Level Fluctuations in Riparian Vegetation： An Analysis in Hay Creek, Whitetail Basin, Montana

The hydrogeology of first-order streams have been evaluated from 2007 to 2009 as part of the Whitetail Basin Watershed Restoration Project in Hay Creek Canyon located 25 km north of Whitehall Montana, USA. An in-depth study of the riparian area hydrogeology started in the fall of 2007 with the installation of more than 40 hand-augered deeper （〉 1 m） wells to complement preexisting driven metal pipe piezometers （± 1 m） installed in four first-order drainages. Two zones within the shallow alluvial systems were identified. This paper presents the results of a concentrated study conducted in the Hay Creek drainage within the tWO zones. Data loggers placed in some of the wells led to a gradual understanding of the water-level patterns in different vegetative types （Douglas Fir, Aspen, Willow-Alder. and Grass-Sagebrush） over the various seasons. The deeper water-level responses change from seasonal patterns to strongly diurnal during summer months. Diurnal patterns continue until leaves drop from riparian vegetation. This was expected, however, the Douglas fir trees show the same pattern. Near the end of the study a full year of water-level data showing the seasonal behavior changes were collected. Resaturation of the upper zone occurs in the fall with sources of recharge coming from up-drainage. A detailed evaluation of water-level responses from up-drainage to down-drainage piezometers occurs in a ＂wave-like＂ resaturation phenomenon that allows one to estimate the bulk hydraulic conductivity of the ＂alluvial system＂ aquifer using principles of Darcy＇s Law. The methods used to evaluate the hydraulic properties and seasonal water-level patterns are presented.

Effects of Sand-Harvesting on River Water Quality and Riparian Soil Physico-Chemical Properties

The widespread distribution of river sand-harvesting activities continues to degrade river water quality and the surrounding riverine environments. This study determined practical effects of sand-harvesting on two rivers in Kakamega County Kenya. Water samples were tested for turbidity and total suspended solids (TSS). For riparian soils, nitrogen (N), phosphorus (P), pH, organic carbon (OC), moisture content and textural class were determined on composite samples obtained from the field. Two control sites not affected by sand-harvesting were also used for comparison. Results indicate TSS concentrations increased during the rainy season when sand-harvesting was occurring, with significant differences between the control and sand-harvesting sample groups. Between seasons—dry and wet—in natural circumstances, the riparian soil moisture and phosphorus contents increased significantly. The study shows that river sand-harvesting degrades the aesthetic value of riparian areas, and makes rivers prone to bank erosion, and silt. This increases river water turbidity. The study concludes that sand-harvesting does not directly affect the riparian soil moisture content, total N, P, pH, OC or textural class, but reduces productivity of riparian land and puts the riverine ecosystems at risk.

小浪底库区河岸带植物物种多样性与土壤因子的关系

以黄河中游末端地段小浪底库区河岸带为研究对象,采用典型对应分析法(CCA),对物种分布和多样性与土壤因子的关系进行研究。结果表明,小浪底库区河岸带共发现植物31种,17科28属,其中禾本科、菊科、蓼科和锦葵科植物最多,苍耳和狗牙根为优势种。随着河流流向小浪底库区南北两岸的有效磷和有机质呈下降趋势;速效钾、含水量和全氮无显著变化。从变异系数看,土壤含水量、有机质、速效钾、全氮及有效磷均属于中等变异程度(0.1≤C≤1),表明土壤养分分布总体上呈现中度不均匀的特征。在6个土壤环境因子中,含水量、pH与有机质含量对小浪底库区河岸带物种多样性的影响较大,土壤速效钾、有效磷及全氮对各种多样性指数影响均不明显。其中,香农-维纳指数与含水量和有机质具有显著相关性(P<0.05);均匀度指数和含水量之间具有显著的相关性;丰富度指数与pH之间具有显著的相关性(P<0.05)。CCA排序显示土壤全氮、pH、有机质和含水量是影响群落分布的主要因子。香附子、牵牛花和荔枝草的分布主要受到全氮的影响;春蓼、野菊等主要受到pH的影响;柳树、牛筋草、大狼杷草主要在含水量和全氮高的环境下分布较多;椿树、榆树等主要在有机质和pH相对较高的区域分布。苍耳、狗牙根、狗尾草等物种广泛分布在样地内,受土壤因子影响较小,对范围的适应较强。

Estimation of soil reinforcement by the roots of four postdam prevailing grass species in the riparian zone of Three Gorges Reservoir, China

Soil erosion and bank degradation is a major post-dam concern regarding the riparian zone of the Three Gorges Reservoir. The development and succession of vegetation is a main countermeasure,especially to enhance bank stability and mitigate soil erosion by the root system. In this study, the roots of four prevailing grass species, namely, Cynodon dactylon, Hemarthria altissima, Hemarthria compressa, and Paspalum paspaloides, in the riparian zone were investigated in relation to additional soil cohesion. Roots were sampled using a single root auger. Root length density（RLD） and root area ratio（RAR） were measured by using the Win RHIZO image analysis system. Root tensile strength（TR） was performed using a manualdynamometer, and the soil reinforcement caused by the roots was estimated using the simple Wu＇s perpendicular model. Results showed that RLD values of the studied species ranged from 0.24 cm/cm3 to20.89 cm/cm3 at different soil layers, and RLD were significantly greater at 0–10 cm depth in comparison to the deeper soil layers（＆gt;10 cm）. RAR measurements revealed that on average 0.21% of the reference soil area was occupied by grass roots for all the investigated species. The measured root tensile strength was the highest for P. paspaloides（62.26MPa） followed by C. dactylon（51.49 MPa）, H.compressa（50.66 MPa）, and H. altissima（48.81MPa）. Nevertheless, the estimated maximum root reinforcement in this investigation was 22.5 k Pa for H.altissima followed by H. compressa（21.1 k Pa）, P.paspaloides（19.5 k Pa）, and C. dactylon（15.4 k Pa） at0–5 cm depth soil layer. The root cohesion values estimated for all species were generally distributed at the 0–10 cm depth and decreased with the increment of soil depth. The higher root cohesion associated with H. altissima and H. compressa implies their suitability for revegetation purposes to strengthen the shallow soil in the riparian zone of the Three Gorges Reservoir. Although the soil reinforcement induced by roots is only assessed from indirect indicators, the present results still useful for species selection in the framework of implementing and future vegetation recovery actions in the riparian zone of the Three Gorges Reservoir and similar areas in the Yangtze River Basin.

How changes of groundwater level affect the desert riparian forest ecosystem in the Ejina Oasis,Northwest China

Groundwater is a key factor controlling the growth of vegetation in desert riparian systems. It is important to recognise how groundwater changes affect the riparian forest ecosystem. This information will not only help us to understand the ecological and hydrological process of the riparian forest but also provide support for ecological recovery of riparian forests and water-resources management of arid inland river basins. This study aims to estimate the suitability of the Water Vegetation Energy and Solute Modelling(WAVES) model to simulate the Ejina Desert riparian forest ecosystem changes,China, to assess effects of groundwater-depth change on the canopy leaf area index(LAI) and water budgets, and to ascertain the suitable groundwater depth for preserving the stability and structure of desert riparian forest. Results demonstrated that the WAVES model can simulate changes to ecological and hydrological processes. The annual mean water consumption of a Tamarix chinensis riparian forest was less than that of a Populus euphratica riparian forest, and the canopy LAI of the desert riparian forest should increase as groundwater depth decreases. Groundwater changes could significantly influence water budgets for T. chinensis and P. euphratica riparian forests and show the positive and negative effects on vegetation growth and water budgets of riparian forests. Maintaining the annual mean groundwater depth at around 1.7-2.7 m is critical for healthy riparian forest growth. This study highlights the importance of considering groundwater-change impacts on desert riparian vegetation and water-balance applications in ecological restoration and efficient water-resource management in the Heihe River Basin.

辽河保护区河岸带植被类型对土壤性质的影响

2010年于辽河铁岭段构建河岸植被缓冲带,设置了杞柳、水蜡、紫穗槐、刺槐、草本和农田撂荒地6种植被带,对不同植被缓冲带下土壤的理化性质进行分析。结果表明:1)不同植被恢复模式下,辽河保护区内河岸带土壤pH值总体呈中性,刺槐地的土壤pH值最高,属于弱碱性土壤,农田地的土壤pH值最低,属于弱酸性土壤。杞柳、水蜡植被带土壤含水率、孔隙度、有机质、阳离子交换量、全氮和碱解氮以及全磷和速效磷相对较高,土壤容重较小;水蜡、刺槐植被带土壤全钾和速效钾相对较高;与其他几种植被恢复模式相比,草本地和农田地的土壤容重相对较大,且土壤养分指标基本偏低。2)土壤理化性质相关性分析显示,土壤容重与含水率和孔隙度呈极显著负相关;土壤含水率和孔隙度呈极显著正相关;土壤有机质与阳离子交换量、氮、磷等指标之间存在显著正相关关系。3)土壤质量综合得分结果表明,水蜡、杞柳植被带土壤质量相对较高;自然草本和农田撂荒地土壤质量较低,说明杞柳、水蜡灌木林对于提高河岸土壤肥力,改善土壤结构具有很好的作用。

密云水库岸边带不同高程土壤中多环芳烃的污染特征及其对水体的生态风险

受南水北调及季节性降雨影响,密云水库水位逐年抬升并形成周期性涨落,导致岸边带土壤生态环境发生变化,影响土壤中多环芳烃(PAHs)的储存与释放。为探究其对水体环境的潜在风险,研究采集了高程130~150 m之间的岸边带表层土壤及沉积物,采用GC-MS气相色谱和质谱联用仪,分析了16种优控PAHs的含量水平及组成特征,并对其不同高程分布特征、来源及潜在生态风险进行了研究。结果表明:(1)水库岸边带表层土壤及沉积物中普遍存在16种PAHs,PAHs总含量水平(∑16PAHs)为66.74~481.34 ng·g^(-1),污染水平较库区沉积物低。(2)与库区沉积物中PAHs组成相似,水库岸边带土壤及沉积物中PAHs主要以中低环为主,萘、菲、蒽、芘为优势化合物;源解析表明,库区岸边带土壤及沉积物中PAHs的主要来源为当地生物质(农田残渣、草木)燃烧,与人类活动有密切联系。其中白河入库处表现出混合源的特征,来源与石油排放污染有关。(3)130~140、>140~145、>145~150 m的3个高程范围内∑16PAHs分别为177.06、223.86和212.63 ng·g^(-1),且低环PAHs为主要组成组分。(4)生态风险评估表明,水库岸边带土壤大部分样点产生负面生态效益的可能性较低,仅有白河入库淹没区、库北淹没带及库东区具有潜在生态风险。

辽河流域河岸带植被多样性特征与空间分布规律研究

河岸带生物多样性对治理河流及水土污染、排流截污、调节水量、稳定河岸、调节局部气候发挥着重要作用,也具有重要的景观功能.本文通过对辽河干流上下游8个研究区的河岸带植被多样性、均匀度、丰富度等多样性指标进行调查,分析了辽河干流植被多样性空间分布特征.结果表明,辽河干流河岸带植被共51科128属165种,以菊科、禾本科为主.2020年辽河干流研究区域Shannon-Weiner多样性指数平均为2.54,2021年为2.38.2020年均匀度指数0.20~0.61,2021年为0.77~3.17.2020—2021年辽河河岸带植被多样性波动不大,中游段植物多样性等特征较好,与人为干扰较少、封育措施较好有关,下游多样性较低,因与城市较近,受到干扰较多有关.本研究为辽河河岸带生态功能恢复与保护提供理论依据.

三峡库区消落带草本植物根际细菌群落季节变化特征及功能预测

为了研究三峡库区消落带人工修复植被下不同季节根际细菌群落特征,选取位于三峡库区核心地带的忠县石宝镇汝溪河流域消落带生态修复示范基地内两种适生草本狗牙根(Cynodon dactylon)、牛鞭草(Hemarthria altissima)根际土壤进行16S rDNA高通量测序。研究结果显示:在消落带退水后的春季、夏季、秋季3个季节共检测到细菌60门、151纲、403属,主要优势门为变形菌门、酸杆菌门、拟杆菌门;放线菌门和芽单胞菌门的相对丰度在季节水平上存在差异,夏季芽单胞菌门丰度较高,秋季放线菌门相对丰度显著减少。适生草本的根际土壤细菌α多样性表现出一定的季节变化规律,即秋季>夏季>春季;通过冗余分析发现,影响细菌群落结构的环境因子主要有土壤全磷(TP)、速效钾(AK)、含水量(SWC)、有机质(OM)。基于未观测状态重建的群落系统发育研究(PICRUSt2)功能预测共发现6个一级功能层和45个二级功能层;代谢功能在一级功能层中占比最高,其有利于提高消落带适生草本植物抑制病原菌的能力,促进植物的生长;一级功能层中有两个功能基因表现出季节差异,二级功能层中有14个子功能的相对丰度在不同季节存在显著差异。由此可见,根际细菌群落对狗牙根、牛鞭草两种草本植物能够广泛分布且适生于三峡库区消落带的土壤环境起到了重要的促进作用。

平原沙土区河岸带不同植被类型对土壤氮组分及酶活性的影响

[目的]明晰河岸带不同植被类型对土壤氮含量及酶活性的影响程度,以期为平原沙土区河岸带的植被构建和土壤养分固持提供依据。[方法]以江苏省平原沙土区丰县复新河河岸带15年生杨树纯林、柳树纯林和杨柳混交林为研究对象,测定5个土层深度(0—20 cm,20—40 cm,40—60 cm,60—80 cm,80—100 cm)的氮组分含量及酶活性,探讨不同植被类型中土壤氮含量和酶活性与土壤环境因子间的关系。[结果](1)各植被类型中,土壤全氮、铵态氮、硝态氮和微生物生物量氮含量均高于对照,60—100 cm深层土壤氮含量在垂直分布上没有表现出明显规律。土壤全氮含量变化范围为0.20~0.75 g/kg,大小顺序为杨树纯林>柳树纯林>杨柳混交林,总体上均随着土层深度的增加而降低,在0—20 cm土层中的含量显著高于其他4个土层。土壤铵态氮和硝态氮含量在杨树纯林中最高,且在杨树纯林中整体上随着土层深度的增加而降低。土壤微生物生物量氮含量在杨柳混交林中最高,在杨树纯林中最低。(2)土壤脲酶、硝酸还原酶、亚硝酸还原酶活性变化范围为0.30~4.35,0.05~0.21,0.46~0.59 mg/(g·d),3种酶活性在杨树纯林中最高,在不同植被类型和土层中存在显著差异(p<0.05)。(3)冗余分析表明土壤有机碳含量、细根生物量和凋落物生物量是影响土壤氮含量和酶活性的主导因子。[结论]试验地杨树纯林由于土壤有机碳含量、细根生物量和凋落物生物量较高导致土壤氮含量和酶活性最高,因此在平原沙土区河岸带选取适宜的植被类型可以提高土壤氮素的固持能力,进而可能会减少土壤养分的流失。

密云水库2022年营养盐时空分布与原因分析

2020年9月,南水北调工程停止向密云水库反向输水,库区水体来源相对稳定。对库区整体营养盐时空分布的探究,可以揭示库区水环境变化,对指导密云水库水质安全管理调度具有重要意义。通过对密云水库2020-2022年总氮(TN)、总磷(TP)、氨态氮(NH_(4)^(+)-N)、硝态氮(NO_(3)^(-)-N)四项营养盐成分的对比分析,可以看出:2022年库区水体营养盐呈上升趋势,NH_(4)^(+)-N和NO_(3)^(-)-N变化趋势相似,表现为浅水区域较高,深水区域较低;TN与TP的变化趋势相似,表现为浅水区域较低,深水区域较高。上游入库水体携带高营养盐可能是库区水体营养盐升高的原因之一;蓄水量对库区营养盐的影响具有多面性;浮游藻类对营养盐的利用对营养盐浓度以及分布的影响较小;新增淹没区土壤营养盐物质的释放对库区水体的营养盐含量影响较小;库滨带植被的淹没致死在一定程度上推动了密云水库营养盐含量的升高。

湘江长沙城区段河岸带植物区系分析

为促进湘江流域河岸带生态恢复与重建及生物多样性保护,运用样地调查、植物区系和统计分析的方法,对该区域植物物种的基本构成、地理成分进行分析。结果表明,研究区共有维管植物30科58属62种,其中有蕨类植物1种,种子植物61种,分属29科57属,占湖南种子植物比例较低,说明该区域植物种类相对较少。单属科和单型属所占比例大、优势科明显,反映出水陆交错带的复杂环境对植物的干扰。科可分为4个分布型和2个变型,属可分为11个分布型和4个变型,说明该区域植物区系地理联系广泛。科和属的分布型说明该河岸带种子植物区系泛热带亲缘性,反映出湘江地处亚热带季风气候的特征,也说明其在本区域植物区系中占有一定地位。

太湖五里湖非点源污染物的来源与控制对策

现场调查显示,五里湖非点源污染物来源于城区道路、居民区、农业和绿化施肥等方面,在降雨时通过河道、湖周散流和大气沉降方式入湖.根据流域环境特点,将五里湖流域划分为西南山地风景旅游管理区,北部新城污染控制区和东南农业、渔业综合整治区3个区域类型,并对各区提出了如下的非点源污染控制对策:西南山地风景旅游管理区需采取陆上植被保护和滨水植被恢复工程;北部新城污染控制区需采取滨水区、河口区、河道区植被恢复工程以及人工湿地工程;东南农业、渔业综合整治区需采取有机农业工程、污水处理工程、植物塘净化工程和河道生态净化工程.

二道白河河岸带植物群落最小面积与物种丰富度

河岸带是森林小流域单元的重要组成部分之一 .由于河水的影响和边缘效应等因素的综合作用 ,河岸带植物群落与远离河岸带的森林群落在组成、结构和分布格局等方面存在较大差异 ,其群落最小面积也不同 .本文对长白山原始阔叶红松林河岸带植物群落最小面积和物种丰富度进行了探讨 .结果表明 ,河岸带植物群落的最小面积均小于远离河岸带的森林群落的最小面积 .在河岸带 ,阔叶红松林群落的 6 0、80和 90 %植物种类时的平均最小面积分别约为 80、180和 32 0m2 ;而远离河岸带的森林内部 ,相应的平均最小面积分别为 2 6 0、380和 480m2 左右 .

辽宁太子河河岸带草本植物特征研究

应用样方法研究了辽宁太子河河岸带草本物种组成特征。结果表明:1)太子河河岸带共有草本植物207种,隶属于36科125属。其中菊科物种最多,水蓼出现的频率最高;2)太子河河岸带草本植物属级区系组成丰富,以温带分布区类型为主,其次为热带分布区类型;3)所有物种中,水生或湿生植物120种,旱生或中生植物87种,分别占总物种数的58.0%和42.0%;4)根据物种在样方中出现与否,将样点分为2类;一类分布于高海拔地区,物种以旱生或中生植物为主,物种数多,而另一类分布于低海拔地区,物种以水生或湿生植物为主,物种数较少;5)河岸带草本物种中有杂草和人类伴生种出现,且频率较高,表明太子河河岸带受到人类活动,如农田开发、挖沙和人类居住的影响。

祁连山黑河源区八一冰川—黄藏寺段河水水文地球化学特征

黑河源区河水水文地球化学特征的研究有助于了解黑河源区河水沿流域水质变化概况,对黑河源区生态环境的保护具有积极意义。以黑河源区干流为研究对象,对河水进行取样检测,结果显示:河水化学组成以K^+、Na^+、Ca^(2+)、Mg^(2+)和Cl^-、NO_3^-、HCO_3^-、SO_4^(2-)为主。通过聚类分析、舒卡列夫分类和Piper三线图分析发现主要离子中,阳离子主要来源于石灰岩风化产物,SO_4^(2-)主要来源于蒸发岩矿物风化产物和人类活动,HCO_3^-主要来源于纯碳酸盐风化产物。通过对重金属污染调查发现,V、Co、Cu、Pb、Cr、Mn和Zn含量较高,矿山开采是重金属污染的主要来源。

城市化地区河岸带植被特征及其与河岸硬度的关系——以晋江市为例

确立了滨河河道硬度与滨河土地硬度两个指标,用以研究城市化地区河岸带的植物构成、多样性与均匀度、优势植物等特征与河岸硬度的关系。选定晋江市都市区12条主要河流作为研究对象,通过样地调查收集数据,并采用相应指数进行数据处理分析,结果表明:(1)调查河流的河岸带植被物种共计70科143属159种,其中乔木20科30属41种,灌木15科15属20种,草本35科98属98种,草本居主导地位,河流间种类分布不均衡;(2)河岸带植物乔灌草区系均以广义热带性成分居多,其次为世界性成分、温带性成分,无中国特有分布类型,乔木中广义热带成分占绝对主导,直观反映地带性特征,灌木与草本中的温带成分多于乔木中的温带成分,类型趋于多元,种类更丰富;(3)从河岸植被优势植物构成来看,主要优势乔木与灌木基本为本土植物,而主要草本中外来植物入侵严重,对地带性植物景观的指示显然不及乔木与灌木;(4)从河岸植被的人工美学属性来看,灌木优势植物中园林观赏植物的种类数显著多于乔木、草本优势植物,反映出晋江人工审美主导的滨河景观空间主要改变与塑造了灌木层植被景观;(5)从河岸植物的人居需求属性来看,龙眼、杨桃等多见于庭院林、水岸林的水果树种也在河岸植被中频繁出现,反映出人口密集区由于对植物生产用途的重视而对河岸植被产生的影响;(6)滨河土地硬度与河道硬度对河岸带灌木植物的影响最强烈,二者均对河岸带植物多样性造成威胁,且前者具有更大的影响力,而后者直接影响了河岸植物的分布形态,出于生产与审美目的的人为干扰对河岸带植物优势种的影响力随滨河硬度的增加而加强,低滨河硬度有助留存原生植被群落;(7)天然弯曲的河流形态对河流植被特征具有积极影响,有助于保留更多本土植被类型,并能在某种程度上丰富乔灌草的植物种类,但这种缓和作用无法根本扭转河岸硬化对植物多样性的胁迫影响。研究表明,城市化地区河流的岸带植被特征与沿线人为干扰类型和强度密切相关,恢复与塑造河岸生态景观要以乡土植被为主,通过乔木景观塑造地带性景观,并以灌木与草本丰富植被景观。