Evaluation of the triflumuron and the mixture of Bacillus thuringiensis plus Bacillus sphaericus for control of the immature stages of Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) in catch basins

INTRODUCTION: In Cali, Colombia, catch basins (streetside storm drains) are one of the main larval habitats of Aedes aegypti and Culex quinquefasciatus. Since 1999, these mosquitoes have been controlled by the Secretaría de Salud Municipal (Secretary of Municipal Public Health) using the larvicide triflumuron. Because of high densities of these mosquitoes that remain in the city, treatment failure was suspected -possibly insecticide resistance of the target species. OBJECTIVES: The efficacy of triflumuron and VectoMax (biorational mixture of Bacillus thuringiensis var. israelensis plus Bacillus sphaericus) were evaluated in the control of A. aegypti and C. quinquefasciatus in catch basins. The residual effect of a single application of the biorational formulation was determined in catch basins during periods of high and low rainfall. MATERIALS AND METHODS: The efficacy of the products was measured in 60 catch basins located in a residential neighborhood of Cali for a period of 90 days. The mean number of immature instars (A. aegypti and C. quinquefasciatus larvae and pupae of both species) was determined biweekly from 40 catch basins with insecticide intervention (20 treated with triflumuron, 20 with VectoMax) and 20 untreated (control group). The residual effect of the biorational larvicide was evaluated biweekly in 10 catch basins during each of the 2 climatic periods. Results. The catch basins treated with VectoMax presented a significantly lower mean number of immature instars of both species compared with the control ( p<0.01). In contrast, the triflumuron treatment significantly reduced only immature instars of A. aegypti compared with the control ( p<0.001). The residual effect of VectoMax was higher during low rainfall compared to the control ( p<0.001). Conclusion. The biorational formulation was the more effective treatment for the control of both species during the period of evaluation (15 days).     

Aedes albopictus (Diptera: Culicidae) in Rome: experimental study of relevant control strategy parameters

Since 1997, Aedes albopictus has colonised and then rapidly invaded the city of Rome (Italy) and its peripheral areas. Presently, the control of this mosquito in Italy relies mainly on larvicidal treatment of street storm sewer catch basins with the organophosphate temephos. We have therefore obtained baseline data on the susceptibility to temephos of the Roman Ae. albopictus population by laboratory bioassays on F1 fourth-instar larvae following standard WHO protocols. Estimated lethal concentrations were 0.014 mg/l (LC50) and 0.022 mg/l (LC90) indicating a lack of resistance to this compound. The persistence of temephos in sewer catch basins was evaluated by follow-up of catch basins treated with a dose of 1.5 mg of active ingredient. Mosquito larvae were recovered in 10% and 50% of the treated basins at 9 and 18 days posttreatment, respectively. In order to understand the relative contribution of this larval habitat to adult populations, we conducted a survey in the Zoo of Rome to estimate the larval density of mosquitoes breeding in sewer catch basins. A complete census of a 16.5 ha area mapped 243 catch basins, but only 25 (10.3%) contained water; of the latter 8 (32.0%) hosted mosquito larvae. All positive catch basins contained larvae of Culex pipiens, which were associated with Culiseta longiareolata and/or Ae. albopictus in 6 and 3 cases, respectively. A longitudinal survey of one catch basin over 4 months showed that the mean larval density of Ae. albopictus was markedly lower than that of Cx pipiens and Cs. Iongiareolata, ranging between 0 and 1.3 larvae/dip as compared to 0-33.2 and 0-22.7 larvae/dip, respectively. However, adult densities of Ae. albopictus in this area estimated during the same period with 20 ovitraps showed consistently high values (proportion of positive ovitraps around 100%). These preliminary observations suggest that whenever alternative larval biotopes other than sewer catch basins are widely available, they might be more productive and/or preferred substrates to catch basins for Ae. albopictus breeding.     

Variation in Aedes aegypti (Diptera: Culicidae) container productivity in a slum and a suburban district of Rio de Janeiro during dry and wet seasons

Seasonal variation in container productivity and infestation levels by Aedes aegypti were evaluated in two areas with distinct levels of urbanization degrees in Rio de Janeiro, a slum and a suburban neighborhood. The four most productive containers can generate up to 90% of total pupae. Large and open-mouthed containers, such as water tanks and metal drums, located outdoors were the most productive in both areas, with up to 47.49% of total Ae. aegypti pupae collected in the shaded sites in the suburban area. Water-tanks were identified as key containers in both areas during both the dry and rainy seasons. Container productivity varied according to seasons and urbanization degree. However, the mean number of pupae per house was higher in the suburban area, but not varied between seasons within each area (P > 0.05). High infestation indexes were observed for both localities, with a house index of 20.5-21.14 in the suburban and of 9.56-11.22 in the urban area. This report gives potential support to a more focused and cost-effective Ae. aegypti control in Rio de Janeiro.     

绿洲景观中居民地空间分布特征及其影响因子分析

以张掖绿洲居民地为研究对象,用景观格局分析软件FRAGSTATS计算了5个景观格局指标,用GIS计算了形状指数、景观类型空间邻接比例、最邻近指数、最近距离以及居民地的耕作半径,借鉴聚落地理学中的居民地分布研究方法,分析了居民地的空间格局特征及其影响因子。结果表明：①耕地是张掖绿洲内的景观基质,居民地是绿洲内分布最广、斑块数最多的景观类型;居民地的平均斑块面积小、形状简单、聚集度高,与耕地的空间邻接长度和数目均最高,其空间分布类型存在空间差异;②耕地是影响居民地分布格局的重要因子。缓冲区分析方法可以从理论上确定居民地的耕作半径,耕作半径与居民地的空间分布类型紧密相关;③居民地到渠系的平均最临近距离为215m,75．6％的居民地中有渠系穿过;④居民地分布受中心城市——张掖市的影响程度极其明显,两者呈指数相关;⑤景观格局分析、居民地分布研究方法和GIS空间分析方法的有效结合,可以较好的反映居民地的空间分布特征及其影响因子的相关性;⑥借鉴聚落地理学的最近邻点指数具有明确的生态含义,可以作为量化景观聚集度的指标。     

Hydroseral development in southern Ontario: patterns and controls

Palaeoecological data from a range of wetland types were synthesized in order to study the development of wetland ecosystems in southern Ontario. The present-day nature of the wetland system occurring in a topographically defined basin was shown to be controlled in part by basin morphology. Stratigraphic and vegetational (pollen and macrofossil analysis) data were used to compare the sequence of communities occupying basins during the postglacial. In systems where terrestrial peat overlies lake sediment, the broad stages of development were relatively uniform (from a lake to a shallow open water wetland to a herbaceous marsh or fen to a woody plant-dominated community), although the exact nature of each stage varied widely between basins. The accumulation rate of sediment within such basins varied by up to two orders of magnitude during the postglacial. Allogenic and autogenic factors have been acting on these systems throughout the postglacial, and the sensitivity of individual sites to changes in these environmental conditions will also have varied. Even the widespread land clearance associated with European settlement in the area in recent centuries has not affected some wetland systems detectably, while others have either been destroyed or profoundly changed. The patterns of hydroseral development, both timing and direction, were compared with known regional environmental changes.     

Genetic pattern of the recent recovery of European otters in southern France

We investigated how landscape affects the population genetic structure and the dispersal of the elusive European otter Lutra lutra in a contemporary colonization context, over several generations and at the level of hydrographic basins. Our study area included 10 basins located in the Cévennes National Park (CNP), at the southern front of the natural otter recovery in France. Each basin comprised 50 to 300 km of permanent rivers that were surveyed for otter presence from 1991 to 2005. Faecal samples collected in 2004 and 2005 in this area were genotyped at 9 microsatellite loci, resulting in the identification of 70 genetically distinct individuals. Bayesian clustering methods were used to infer genetic structure of the populations and to compare recent gene flow to the observed colonization. At the regional level, we identified 2 distinct genetic clusters (NE and SW; FST=0.102) partially separated by ridges, suggesting that the CNP was recolonized by 2 genetically distinct otter populations. At the basin level, the genetic distance between groups of individuals in different basins was positively correlated to the mean slope separating these basins. The probable origins and directions of individual movements (i.e. migration between clusters and basin colonization inside clusters) were inferred from assignment tests. This approach shows that steep and dry lands can stop, impede or divert the dispersal of a mobile carnivore such as the otter.     

Life cycle, horizontal microdistribution and current resistance of Allogamus auricollis Trichoptera: Limnephilidae in an Austrian mountain brook

SUMMARY. 1. The life history, horizontal distribution at the sediment surface and the effect of water flow on the microdistribution of Allogamus auricollis (Pictet, 1834), a case-bearing caddisfly, was investigated in a mountain brook near Lunz, Lower Austria.
2. The average head-width increment per moult was proportionately constant at c . 48%; therefore Dyar's rule was applicable.
3. Allogamus auricollis has a 1-year life cycle with first and second instars most abundant in October. It overwinters primarily as third and fourth instars; pupae were observed in August.
4. Horizontal distribution patterns were investigated by means of bimonthly samples taken along the stream profile. All instars were most abundant near the banks: 86.5% of the total catch 1987–88 were collected 0–1.5 m from the banks.
5. Current speeds were measured at the sites of 2191 larvae (including all instars) and eighty-six pupae. Larvae were most abundant at current speeds of 0–5 cm s⁻¹ (i.e. 86.6% of the total catch 1987–88).
6. Laboratory data on different stages of resistance to drift in A. auricollis (Waringer, 1989) were tested for their application to field conditions. 90% of the total catch 1987–88 preferred areas at the substrate surface where they could remain fully retracted within their cases, unattached, even when the large lateral case surface area was directed towards the water flow. This was also true at times of high discharge where the size of these areas was considerably reduced.     

Variability of Anthropogenic and Natural Compounds in High Altitude–high Accumulation Alpine Glaciers

Mid-latitude glaciers represent one of the most important archive of environmental and atmospheric data. In the absence of summer melting, the accumulation of snow on the upper part of mountain chains can allow preservation of the chemical, isotopic and insoluble mineral dust composition of the atmosphere in stratigraphic sequence. The European Alps are located in an area of intense human impact, lying in between some of the most industrialized countries of the world (Italy, France, Germany) and facing the Mediterranean basin. Ice cores recovered from alpine sites above 4000 m a.s.l., where the mean annual temperature is normally below −10 °C, allow obtaining precious environmental records. While low-accumulation high-altitude sites provide the longest alpine sequences (Colle Gnifetti, Italian Alps), high-accumulation sites as Col du Dome (CDD, French Alps) and Colle del Lys (CDL, Italian Alps), both located about 4250 m a.s.l. are suitable for obtaining information about the seasonal variability of some compounds. We synthesize in this work the main results from alpine ice cores investigations held by various authors, focusing on high-altitude–high-accumulation sites in particular. Behind the seasonal natural variability of the data, all records point out an unequivocal anthropogenic contribution to mid-troposphere pollution during the second half of the 20th century. These changes could have been associated also to modifications of the mean long-range atmospheric circulation patterns within the Mediterranean basin.     

The measurement of aerosolized endotoxin from land application of Class B biosolids in Southeast Arizona

The purpose of this study was to determine aerosolized endotoxin concentrations downwind of a biosolids land application site. Aerosol samples were collected from biosolids land application sites, tractor operation, and an aeration basin located within an open-air wastewater treatment plant. Aerosolized endotoxin above background concentrations was detected from all sites, at levels ranging from below detection up to 1800 EU m-3 of air. Biosolids loading operations resulted in the greatest concentrations of endotoxin (mean 344 EU m-3). As downwind (perpendicular to wind vector) distance increased from sources (2-200 m), levels of endotoxin decreased to near background (without biosolids application) concentrations. Overall, the detected levels of aerosolized endotoxin were within past proposed aerosolized endotoxin limits (250-2000 EU m-3) by other occupational exposure studies. Occasionally, peak concentrations were found to be above these limits. Sites in which soil was being aerosolized resulted in greater concentrations of endotoxin with or without biosolids, which suggested that the majority of endotoxin may in fact be of soil origin. This study evaluated the presence of aerosolized endotoxin from the land application of biosolids and showed that these levels were within ranges for concern suggested by other studies and that this area of research needs further investigation.     

Comparative study of additive basal area of conifers in forest ecosystems along elevational gradients

We examined the basal area of two life forms (conifers vs. broadleaf trees) along elevational gradients on Yakushima Island, Japan and on two series of geological substrate on Mount Kinabalu, Borneo. On Yakushima, total stand basal area abruptly increased from 700 to 1,050 m in accordance with the high dominance of conifers, indicating the presence of additive basal area of conifers in conifer–broadleaf mixed forests at higher elevations (1,050–1,300 m). Along two substrate series on Kinabalu, some forests at higher elevations (1,860–3,080 m) showed relatively high dominance of conifers, but conifer basal area did not appear to be additive. Conifers were emergents above the canopy of broadleaf trees in mixed forests on Yakushima, but two life forms usually coexisted in the single-story canopy in mixed forests on Kinabalu. Litterfall rate as a surrogate of productivity decreased with decreasing temperature along elevation on both the sites, but the rate of decrease was slower on Yakushima, where mixed forests at higher elevations showed relatively high rates. Thus, we suggest that additive basal area of conifers was linked to their emergent status, and that it enhanced productivity by complementary use of light by two life forms that occupy different stories. On Yakushima, typhoons are a major disturbance, but do not severely limit the height growth of conifers, allowing the development of two-story mixed forests. On Kinabalu, a major disturbance is El Niño-driven drought, and hydraulic limitation to tree height may explain the non-additive and non-emergent nature of conifers.     

The influence of temperature and habitat on the distribution of chiselmouth, Acrocheilus alutaceus, in British Columbia

We intensively sampled fish in rivers and streams within a single major drainage basin (the Blackwater River) and across major drainages in British Columbia to assess the factors influencing distribution of chiselmouth, Acrocheilus alutaceus, and to develop models for predicting chislemouth presence. Chiselmouth were typically absent from sites with maximum temperatures below 20°C or 2100 annual degree days, both within a single drainage and between larger drainages. Indices of stream size (bankfull channel width and basin area) were the most significant predictors of chiselmouth presence within the Blackwater drainage (p=0.016 and p=0.032, respectively), and inclusion of thermal variables only marginally increased classification success. In contrast, bankfull channel width and basin area were poor predictors of chiselmouth presence in mainstem habitat within larger drainage basins throughout British Columbia. Inclusion of thermal variables (particularly degree days > 12°C) doubled correct classification rates of chiselmouth presence across larger drainage basins. These habitat associations suggest that water temperature is the primary constraint on presence of chiselmouth populations in larger drainages across a landscape, while selection of different habitat types (mainstem habitat over smaller tributaries) determines distribution within any given basin.     

Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska*

We examined biotic and physiochemical responses in urbanized Anchorage, Alaska, to the percent of impervious area within stream basins, as determined by high-resolution IKONOS satellite imagery and aerial photography. Eighteen of the 86 variables examined, including riparian and instream habitat, macroinvertebrate communities, and water/sediment chemistry, were significantly correlated with percent impervious area. Variables related to channel condition, instream substrate, water chemistry, and residential and transportation right-of-way land uses were identified by principal components analysis as significant factors separating site groups. Detrended canonical correspondence analysis indicated that the macroinvertebrate communities responded to an urbanization gradient closely paralleling the percent of impervious area within the subbasin. A sliding regression analysis of variables significantly correlated with percent impervious area revealed 8 variables exhibiting threshold responses that correspond to a mean of 4.4 – 5.8% impervious area, much lower than mean values reported in other, similar investigations. As contributing factors to a subbasin's impervious area, storm drains and roads appeared to be important elements influencing the degradation of water quality with respect to the biota.     

Comparative Effectiveness of Three Release Rates for a Pteromalid Parasitoid (Hymenoptera) of House Flies (Diptera) in Beef Cattle Feedlots

Muscidifurax zaraptor Kogan and Legner (Hymenoptera: Pteromalidae) was released at three rates in nine beef cattle feedlots in eastern Nebraska to measure dosage response. Dosage response was measured by the percentage parasitism of sentinel house fly pupae. Releases were made from a single location near the center of the pen at three feedlots, from two locations within the pen at three feedlots, and from four corners of the pen at three feedlots. One-time releases initiated held propagation of M. zaraptor using freeze-killed house fly pupae as hosts. Three treatment rates, averaging 4480, 20,300, and 37,100 parasitoids, were released weekly over a 15-week period with each of the three release methods receiving a low, medium, or high treatment rate. All nine release sites produced significantly higher levels of parasitoid emergence and sentinel host mortality than sentinel hosts at two control facilities. The three sites receiving the high treatment rate averaged 38% host mortality, compared with 26% for the medium treatment rate and 17% for the low treatment rate. The two control sites averaged 2% host mortality. No significant differences could be detected in the number of release stations except at the four-station method using the low treatment rate. High temperatures during at least two of the weekly periods were detrimental to the released parasitoids.     

Low diversity and high levels of population genetic structuring in introduced eastern mosquitofish (<Emphasis Type="Italic">Gambusia holbrooki</Emphasis>) in the greater Melbourne area,Australia

Eastern mosquitofish (Gambusia holbrooki) were introduced into Australia in 1925 and released to control mosquitoes. Gambusia holbrooki rapidly became invasive in recipient environments and now threaten native fauna. In this study, we used five polymorphic microsatellite loci and sequence from two mitochondrial genes, cytochrome b and cytochrome oxidase I, to evaluate genetic variation, colonisation and movement patterns of introduced G. holbrooki in the greater Melbourne area, and to assist in identifying the feasibility of local eradication. Microsatellite variation was consistently low within populations and there was evidence of bottleneck events for several populations. Populations displayed significant structuring associated with river basins rather than geographic distance, suggesting that habitat connectivity is important for dispersal. However, a few populations within river basins were more closely related to populations in other river basins than within their own basin, most likely reflecting a role of human-assisted dispersal in population establishment. Mitochondrial sequencing revealed only a single haplotype and suggested all populations were founded by individuals from a common source. These genetic data help delineate boundaries for local management strategies.     

BIODIVERSITY RESEARCH: Native and introduced fish species richness in Mediterranean streams: the role of multiple landscape influences

Aim To examine the role of multiple landscape factors on the species richness patterns of native and introduced freshwater fish. Location Mediterranean streams, south‐western Iberian Peninsula, Europe (c. 87,000 km²). Methods We used a dataset of fish occurrences from 436 stream sites. We quantified the incremental explanatory power of multiple landscape factors in native, introduced, and overall local species richness using regression analysis. First, we related variation in local species richness across river basins to regional species richness (here, the basin species pool), area and factors of climate and topography. Second, we related within‐river basin local species richness to site’s climate and topography, and spatial structure derived from Principal Coordinates of Neighbour Matrices approach, after testing for species richness spatial autocorrelation; predicted local richness was mapped. Results Patterns of local species richness across river basins were strongly associated with regional species richness for overall, native and introduced species; annual rainfall showed a significant incremental contribution to variation in introduced species richness only. Within river basins, environmental factors were associated with local richness for the three species groups, though their contributions to the total explained variation were inferior to those of spatial factors; rainfall seasonality and stream slope were the most consistent environmental correlates for all species groups, while the influence of spatial factors was most prevalent for native species. Main conclusions Landscape factors operating among and within river basins seem to play a relevant role in shaping local species richness of both native and introduced species, and may be contingent on basin‐specific contexts. Nevertheless, local factors, such as habitat characteristics and biotic interactions and human‐induced disturbances may also be at play. Multiscale approaches incorporating a multitude of factors are strongly encouraged to facilitate a deeper understanding of the biodiversity patterns of Mediterranean streams, and to promote more effective conservation and management strategies.     

基于精细尺度的冬季南乔治亚岛南极磷虾渔获率时空与环境效应

南乔治亚岛水域不仅是南极磷虾渔业的主要渔场之一,同时该水域的南极磷虾也是许多以该岛为栖息地的捕食者(如海豹、鲸鱼等)的饵料,因此对该岛南极磷虾资源丰度的研究对于深入理解南极生态系统有着非常重要的作用.本研究基于精细尺度渔业数据,利用广义可加模型(GAM)对2013年冬季南极磷虾渔获率与环境因子之间的关系进行研究.结果表明: 该模型对渔获率总偏差解释率为32.0%,其中贡献最大的为旬别,贡献率为21.4%;其次为纬度,但贡献率显著降低,仅为4.4%.7月上旬至9月上旬,渔获率总体上呈下降趋势.渔场东侧渔获率较高,尤其是中东部海域,而北侧的渔获率相对偏低.随着地形变化程度的增大,平均渔获率呈下降趋势.风力处于4级以下的情况不仅适宜捕捞作业,且渔获率也处于较高的水平.风向并不会对渔获率产生显著的影响.在表温0.5~2.0 ℃范围内,随着表温的增加,平均渔获率呈上升趋势.     

Ranging behaviour and foraging habitats of breeding Sparrowhawks Accipiter nisus in a continuous forested area in Norway

The ranging behaviour and foraging habitats of Sparrowhawks Accipiter nisus were studied in a continuous forest area in southern Norway by use of radiotelemetry in 1995 and 1996. The mean size of the home ranges was 9.2 km² for males (sd ± 3.7, n = 6) and 12.3 km² for females (sd ± 6.4, n = 6), but the difference was not significant. Females ranged farther away from nests (mean 1824 m) than did males (mean 1240 m). None of the Sparrowhawks were located outside forest habitats. For the three pairs where both mates were radiotracked in 1996, habitat use did not differ between the sexes. Habitat composition in the home ranges differed from that of the study area. The most important difference was a higher proportion of medium-aged forest and a lower proportion of old forest in home ranges than in the study area. The selection for medium-aged forests was probably a response to high food supply and good hunting opportunities. Mixed regeneration and old forests were used more than clear-fell areas, which were seldom used. Mixed regeneration was also used more than coniferous replanting. The large home ranges in this study compared with those in studies in Great Britain is probably due to lower land productivity and associated lower densities of prey species in the present study. The study indicates that the Sparrowhawk benefits from modern forestry, which has created an increased proportion of medium-aged stands in the forest landscape.     

Cadmium contamination in various environmental materials in an industrial area,Hangzhou, China

Abstract

Due to the location of manufacturing in north Hangzhou, many residential areas are close to trunk roads and factory areas. This potentially exposes citizens to pollution sources such as industrial emissions and vehicle exhaust. Because pollution by cadmium (Cd) is of great concern, an extensive survey was conducted in north Hangzhou city to study the current condition of Cd contamination and any resulting hazard. Environmental materials including water, bottom mud, urban green-land soil, street dust and moss were collected. Cd concentration and chemical partitioning in the samples were determined. The results indicate that all the media in north Hangzhou have elevated Cd concentrations, the Cd conten trend being: factory area >traffic area > residential area. The chemical partitioning results show that Cc in topsoil and street dust presents are mobile (9–61% Cd are bound in acetic acid extractable phase) which suggests a high ecological hazard potential. Environmental bioindicator moss samples were found to be loaded with Cd revealing high bioavailability of Cd in various media in north Hangzhou This confirms the possibility of Cd being a potential biohazard in this location.     

Landscape ecotoxicology of coho salmon spawner mortality in urban streams

In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to spawn in urban basins of the Puget Sound region have been prematurely dying at high rates (up to 90% of the total runs) for more than a decade. The current weight of evidence indicates that coho deaths are caused by toxic chemical contaminants in land-based runoff to urban streams during the fall spawning season. Non-point source pollution in urban landscapes typically originates from discrete urban and residential land use activities. In the present study we conducted a series of spatial analyses to identify correlations between land use and land cover (roadways, impervious surfaces, forests, etc.) and the magnitude of coho mortality in six streams with different drainage basin characteristics. We found that spawner mortality was most closely and positively correlated with the relative proportion of local roads, impervious surfaces, and commercial property within a basin. These and other correlated variables were used to identify unmonitored basins in the greater Seattle metropolitan area where recurrent coho spawner die-offs may be likely. This predictive map indicates a substantial geographic area of vulnerability for the Puget Sound coho population segment, a species of concern under the U.S. Endangered Species Act. Our spatial risk representation has numerous applications for urban growth management, coho conservation, and basin restoration (e.g., avoiding the unintentional creation of ecological traps). Moreover, the approach and tools are transferable to areas supporting coho throughout western North America.     

Response of biota to land use changes and water quality degradation in two medium-sized river basins in southwestern Greece

To assess biotic responses to anthropogenic pressures, a seasonal monitoring of benthic macroinvertebrates, physicochemical and hydromorphological parameters has been applied in 11 sites along two highly impacted river basins in southwestern Greece, mainly during the year 2006. In the first river basin, the upper reaches were covered by thick riparian forest, replaced by intensive agriculture and livestock in the mid-reaches, while the lower parts were characterized mainly by agroindustrial activities. The second river basin was impacted by the discharge of raw cheese whey effluents in the mid-reaches, while the lower parts were protected by thick riparian vegetation. The mid- and lower parts of the first river basin (Peiros–Parapeiros rivers) were impaired by dam constructions, agricultural intensity and urbanization. In the second river basin (Vouraikos river), the 3/5 of the river length, located in the mid-reaches, was degraded due to the discharge of untreated cheese whey effluents. Water quality of the lower reaches was highly recovered due to the presence of thick riparian vegetation. Macroinvertebrate diversity was strongly correlated to pollution, as sites with major physicochemical and hydromorphological degradation presented low taxonomic richness and diversity values, while non-impacted sites were characterized by a considerable presence of E.P.T. taxa and higher diversity. The current study indicates the significant impact of land use changes to the water quality, which consequently influence the distribution of biota, pointing out the critical role of the riparian vegetation to the detoxification of surface waters.