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1.
Alberto Doretto Francesca Bona Elisa Falasco Daniele Morandini Elena Piano Stefano Fenoglio 《河流研究与利用》2020,36(1):91-101
Droughts are affecting an increasing number of lotic ecosystems worldwide due to the combined effects of climatic and anthropogenic pressures. Unlike naturally intermittent rivers, where the drying phase is a part of the annual flow regime, water scarcity in Alpine rivers represents a relatively recent phenomenon and, therefore, a major threat for the biodiversity of these lotic ecosystems. However, Alpine stream community response to drought is still poorly investigated. Here, we assess the recovery of macroinvertebrates in two Alpine streams after a supraseasonal drought. As water returned, a total of 10 sampling sessions were carried out, and temporal patterns in diversity, density, and taxonomic composition of benthic communities, as well as in the percentage of functional feeding groups, were investigated. We found that the resistance of invertebrate communities in Alpine streams is generally low: drought markedly reduced the diversity and density of macroinvertebrates. Conversely, our results suggest that the passive dispersal by drift from the upstream river sections seems the most probable mechanism promoting the post‐drought recovery. Nevertheless, this resilience ability appears to be stream specific and influenced by intrinsic stream characteristics, including the flow permanence and distance from the nearest upstream perennial reach. This work sheds light on the ecological consequences of droughts on macroinvertebrate communities. As flow intermittency in Alpine areas is expected to intensify under current global change scenarios, results of this study provide important information to predict changes in the taxonomic composition and diversity of macroinvertebrate communities. 相似文献
2.
Recolonization by native species following reintroduction can affect resident species through a variety of processes. We examined the effects of natural recolonization by coho salmon Oncorhynchus kisutch on sculpin (Cottus rhotus and Cottus gulosus), small benthic fishes, in a small forest stream in Western Washington, USA. Provision fish passage around a small dam allowed coho access to habitat, which had been inaccessible for over 100 years. We found that density (g m?2 and number m?2) was unchanged, and body condition (the slope of the relationship between length and weight) of sculpin tended to increase from before relative to a 5‐year period following recolonization. The proportion of sculpin comprising the total fish assemblage decreased after coho colonization relative to before but remained stable for a 5‐year period after coho reintroduction, whereas coho density increased over fivefold. Additionally, we used Akaike's information criteria to evaluate the relative importance of physical and biological variables to predict sculpin density in pool habitats during the initial coho recolonization period. Physical microhabitat variables had little support for predicting sculpin density, whereas there was a significant support for stream temperature; cutthroat trout (Oncorhynchus clarkii) density and year were the most important predictors of sculpin density. Coho density was not significant in any model. Our results indicate coho introduction and subsequent recolonization have to date had minimal individual or population level effects on sculpin, therefore demonstrating that species reintroductions into their native range can have no measurable effect on resident organisms. Published 2013. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
3.
Alastair M. Suren Tenna Riis Barry J. F. Biggs Shelley McMurtrie Rachel Barker 《河流研究与利用》2005,21(4):381-401
Effects of stream enhancement on habitat conditions in five spring‐fed urban streams in Christchurch, New Zealand, were investigated. Stream enhancement consisted of riparian planting at three sites, and riparian planting and channel modifications at two sites, where a concrete dish channel and a timber‐lined channel were removed, and natural banks reinstated. Sites were surveyed prior to enhancement activities and 5 years after, and changes in riparian conditions (composition, horizontal and vertical cover), instream conditions (bank modifications, inorganic and organic material on the streambed), and hydraulic conditions (wetted perimeter, cross‐sectional area, depths and velocities) quantified. Enhanced sites generally had higher marginal vegetation cover, as well as increased overhanging riparian vegetation, reflecting planting of Carex sedges close to the water. Bed sediments changed at some sites, with the greatest change being replacement of a concrete channel with gravel and cobble substrate. Bryophyte cover declined at this site, reflecting loss of stable habitat where these plants grew. Bed sediments changed less at other sites, and cover of fine sediments increased in some enhanced sites, presumably from sediment runoff from nearby residential development. Filamentous algal cover decreased at one stream where shade increased, but increased in another stream where the removal of timber‐lined banks and creation of a large pond decreased shade. Stream enhancement increased variability in velocity at three of the five sites, but overall changes to stream hydraulics were small. Although enhancement activities altered the physical conditions of the streams, major changes occurred only to riparian vegetation and bank conditions. Lack of other major changes to instream physical conditions most likely reflected the limited range of channel morphology alterations undertaken. Moreover, the flat topography of Christchurch and naturally low stream discharge further constrained changes to instream physical conditions from enhancement activities. Sediment inputs from continuing urban development also negated the effects of adding coarse substrates. These over‐arching factors may constrain the success of future stream enhancement projects within Christchurch. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
4.
Invertebrates were compared upstream versus downstream from diversions on three small, headwater streams in the central Rocky Mountains, USA. Flow alteration of these streams varied from mild (some aspect of all natural flow components was transferred downstream) to severe (nearly 100% of the flow was diverted for 10–11 months of the year). The analysis was separated into periods of frequent (diversion gates often opened and closed; April–October) and infrequent flow fluctuations (stable low flows due to constant diversion; November–March). Invertebrates appeared resilient to mild flow alterations as neither the abundance, diversity, nor spatial and temporal variation in abundance and diversity differed upstream versus downstream during either period. In severely diverted streams, however, total invertebrate density downstream from the diversion was only 50% of upstream. Invertebrate diversity was also reduced; ten taxa abundant upstream were absent in downstream sections. Chironomids, ostracods and Ameletus spp. comprised 80% of total invertebrate density during constant, low flow conditions in the severely diverted streams. Although all taxa in the severely diverted streams recovered (drift) during the period of frequent flow fluctuations, spatial and temporal variation (coefficient of variation) in both density and the number of taxa was significantly greater downstream. Depending on the frequency with which free‐flowing conditions were re‐established, many invertebrate populations (especially mayflies and some stoneflies) declined or were even locally extirpated (e.g. Hesperoperla pacifica, Megarcys signata, Neothremma alicia, Polycelis coronata). Downstream communities in severely diverted tributaries appeared to fluctuate between two stable endpoints; a depauperate low‐flow community dominated by chironomids and ostracods and a more abundant and diverse natural‐flow community dominated by mayflies, chironomids, ostracods, stoneflies and caddisflies. Water abstraction (extent and timing of diversion) could be managed to minimize risks to downstream ecological resources. 相似文献
5.
Headwater stream morphology is a direct reflection of watershed characteristics and therefore can inform our understanding of anthropogenic influence on channel geometry and sediment dynamics. Little knowledge of the geomorphology of headwater streams in the Ozark Plateaus region of northwest Arkansas exists. The Illinois River watershed, in northwest Arkansas, is of critical interest within the region because of land use changes in the headwaters due to rapid population growth. A mixture of forest and agricultural (open pasture and poultry houses) land use dominates the watershed, but urban areas are rapidly expanding. These land use types: forest, agriculture and urban are an effective proxy for increasing anthropogenic disturbance. Analysis of longitudinal profile, cross‐section and sediment distribution in streams from each land use type shows a strong trend of increasing slope and channel cross‐sectional area with a greater degree of anthropogenic disturbance. Additionally, urban streams are characterized by the presence of exposed bedrock in the stream bed, while agricultural and forested streams are gravel mantled. These data have important implications for current and future stream management policies and practices regionally. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
6.
M. J. Feio W. R. Ferreira D. R. Macedo A. P. Eller C. B. M. Alves J. S. França M. Callisto 《河流研究与利用》2015,31(1):70-84
Here, we set target values to measure the ecological improvement of streams, based on invertebrate communities, riparian vegetation, instream habitat conditions and water chemistry. The study area is a large tropical catchment (Rio das Velhas, Minas Gerais, Brazil) affected by pastures, mining areas and a large urbanized area but also includes natural protected areas. Two stream types were found in the catchment, based on stream size, elevation, climate and geology with significantly different macroinvertebrate communities. In spite of a marked wet/dry seasons' climatic pattern, that does not result in the segregation of communities. Four classes of global degradation (IV—bad to I—good condition) were defined based on the available abiotic information, corresponding to a gradient in structure and biotic metrics of macroinvertebrate communities, matching the current knowledge on taxa sensitivity to pollution and general disturbance. Class I corresponds to target conditions to be achieved under restoration programmes. Using this approach, we were able to detect an improvement of abiotic conditions in four urban streams that benefited from enhancement measures in 2007–2008. However, invertebrate communities improved clearly in only one site (biotic metrics and community structure). Our study highlighted that good water quality alone is not enough and that only the combined effect of water quality, riparian vegetation and instream habitat condition enhancement resulted in the improvement of invertebrate communities. An important limiting factor for macroinvertebrate communities' recovery may be the distance to source populations. We concluded that the combined use of biological and abiotic target values for measuring the recovery of streams is needed to fully achieve an ecological restoration. This approach can also be valuable in the regular monitoring of streams to assess stream degradation. Target values based on other biological elements, such as fishes and algae, and functional processes could also contribute to define more global and realistic goals. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Flow intermittence occurs in an increasing number of streams, due to climate change, local land‐use alteration and water abstraction. In particular, droughts represent a new element in Alpine river regimes, and their ecological consequences are poorly explored. We here used artificial streams to investigate the resilience of macroinvertebrates to drought in Alpine streams based on the presence of pools (i.e., refuges) and drift (i.e., recolonization). Three flumes were selected: 1 with permanent flowing water (Control), whereas the other 2 (Drift+Pools, Only Drift) were subjected to 2 consecutive drought‐rewetting phases. Moreover, to better monitor the recolonization pattern by drift, quantitative samples of drifting taxa were collected using an additional flume (Incoming Drift). The effects of droughts on benthic invertebrate communities and their recovery were assessed in terms of composition, structure, diversity, and stability. Droughts dramatically reduced the taxa richness, especially with regard to the most sensitive and specialized macroinvertebrates, such as Ephemeroptera, Plecoptera, and Trichoptera taxa. Macroinvertebrate assemblages of the flumes that experienced drying phases were dominated by few generalist taxa and showed a higher degree of dissimilarity. Overall, no significant differences were observed in relation to the presence of pools, suggesting a limited role of this habitat in the recovery process. This finding suggests that in shallow and fast‐flowing Alpine lotic ecosystems the drift rather than pool availability represents the main driver of the macroinvertebrate resilience to droughts and provides insights into factors that can facilitate the recovery of aquatic communities after droughts. 相似文献
8.
A. Di Sabatino G. Cristiano D. Di Sanza P. Lombardo C. Giansante R. Caprioli P. Vignini F. P. Miccoli B. Cicolani 《河流研究与利用》2016,32(6):1242-1251
The ecological knowledge of large rivers is still scarce or highly fragmented mainly because of complex, laborious and expensive procedures to collect informative samples from the benthic biota. Standard sampling protocols for macroinvertebrates were mainly developed and calibrated for wadeable streams, while a number of heterogeneous non‐standard sampling procedures are available for large rivers. We propose the new, easy‐to‐build and cost‐effective leaf‐nets (LN) method to quantitatively sample benthic invertebrates in non‐wadeable waterways. The LN method uses Phragmites australis leaves as substrate and combines the characteristics of the leaf‐bags and the Hester–Dendy (HD) multiplates methods. We compared the effectiveness of the LN and HD methods in a near‐pristine and in an impacted stream‐reach (downstream an aquaculture plant) of a non‐wadeable second‐order stream of Central Apennines (Italy). Twenty‐five of the 34 cumulatively collected macroinvertebrate taxa were common to both methods, while seven taxa were found only on LN and two only on HD. Taxonomic richness and total macroinvertebrate abundance were higher for LN assemblages. Number of Ephemeroptera, Plecoptera and Trichoptera taxa (EPT) also tended to be higher on LN. Assemblage composition was different on LN and HD. Both methods documented a significant decrease in EPT taxa and a concomitant increase in the total abundance of more pollution‐tolerant taxa in the impacted stream‐reach, but the LN method was more sensitive to impact‐associated changes in macroinvertebrate assemblage structure. In contrast to the hardboard plates of HD, the assembled leaves of the LN may act as a direct or indirect food source and may better mimic the texture and composition of more heterogeneous natural substrates thus favouring the migration–colonization process from both bottom and littoral benthic invertebrates. The sampling efficiency, cost effectiveness and simplicity warrant the routine use of the new LN method in large‐river ecological assessment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
Large wood (LW) has important physical and ecological functions in streams. Riparian vegetation is extensively removed during urban expansion, and urban streams may experience enhanced fluvial transport of LW due to flashy hydrology. In this study, LW loads were assessed for three reaches on North Buffalo Creek, an urban stream located in Greensboro, North Carolina, United States. These three reaches have similar hydrology but different riparian vegetation densities. We measured the frequencies and sizes of both in-channel LW and riparian vegetation across the three reaches. Our results showed that the recently reforested reach had greater LW volume (22.5 m3/km) compared to the unmanaged forested site (16 m3/km) and the site with low riparian vegetation density (4.78 m3/km). The difference in LW frequency among reaches was statistically significant (). However, the difference in the volume of individual pieces was not significantly different across reaches (, indicating that a similar size of wood is recruited across the three sites. Our findings also showed that there is a positive relationship between riparian vegetation frequency and in-channel LW frequency, which are significantly related as a power function. Spatial lag models (integrating upstream riparian trees) did not show better results compared to a non-lagged model, suggesting that storage and recruitment were predominantly local and that the LW distribution at our reaches is limited by recruitment rather than dominated by fluvial transport. Our findings suggested that a fully forested watershed is not needed to provide some of the benefits of wood to urban streams. 相似文献
10.
The aim of this study was to describe the colonization of the biofilm during its early stages under different concentrations of nutrients and organic matter, specifically in urban streams influenced by agriculture and urbanization. We hypothesized that in a stream with higher concentrations of nutrients and organic matter, the initial biomass growth would be faster, and the changes in the structure of the community would be greater. Sterile glass substrates were placed in 2 urban streams that differed in nutrient and organic matter concentrations; samples were collected during their first week of colonization to measure total biomass, bacterial biomass, chlorophyll a, activity of the electron transfer system, and the community composition. Results show that biofilm development in both streams began within a few hours and differed under different conditions of nutrients; in the stream with a better water quality, the colonization dynamics consisted of 2 increments of bacterial biomass linked with an increase of algal biomass. In the urban stream with higher nutrient and organic matter concentrations, biofilm development was slower and consisted of a simultaneous increase of bacteria and algae, consistent with a lower electron transfer system activity. Therefore, the dynamics of the colonization process in addition to those characteristics of the fully developed biofilm could have potential applications in water monitoring of urban streams. 相似文献
11.
Artificial neural networks were used to pattern the use and partition of riverbed mesohabitats by four coexisting mayflies (Ephemera danica, Rhithrogena semicolorata, Caenis sp., and Serratella ignita), in a fast‐flowing stream. Sixty‐six samples were taken from the various mesohabitat types throughout a one‐year period. Water depth, current velocity, substratum composition, and particulate organic matter were used to describe the mesohabitats within each sample unit. The species and abiotic data were computed separately with the self‐organizing map (SOM) algorithm. Then, using the k‐means algorithm, clusters were detected on the maps and the sampling units were classified separately for each variable and for species densities. Four clusters could be identified on the SOM according to nine environmental variables, and this classification was related to the morphodynamic conditions, chiefly with respect to substrate composition and current velocity. Similarly, three subsets were derived from the SOM according to gradients of species densities. The coincidence between ‘abiotic’ and ‘mayfly’ clusters showed that: (1) E. danica, Caenis sp. and S. ignita used similar mesohabitats, but E. danica was temporally segregated; (2) competition for space was likely to occur between Caenis sp. and S. ignita; and (3) R. semicolorata was spatially segregated from the three other mayflies. The method is discussed with reference to two alternative techniques: habitat preference curves, and multivariate analyses. The former implies a greater computation effort and is rather convenient under applied perspectives. The second approach faces the basic assumption that non‐linear modelling methods should be preferred for dealing with ecological data which vary and covary in non‐linear fashions. By combining ordering and clustering abilities (and other advantages such as gradient analysis and detection of outliers), SOM provides a visual and efficient way to bring out structures in the distribution of co‐occurring species within multivariate microenvironments. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
12.
13.
In Portland (Oregon, USA), restoration actions have been undertaken at the watershed scale (e.g. revegetation and stormwater management) to improve water quality and, where water quality and quantity are adequate at the reach scale, to increase habitat heterogeneity. Habitat enhancement in urban streams can be important for threatened species, but challenging, because of altered catchment hydrology and urban encroachment on floodplains and channel banks. To evaluate reach‐scale restoration projects in the Tryon Creek watershed, we sampled benthic macroinvertebrates and conducted habitat quality surveys pre‐project and over 4 years post‐project. Species sensitive to pollution and diversity of trophic groups increased after restoration. Taxonomic diversity increased after restoration but was still low compared with reference streams. We found no significant changes in trait proportions and functional diversity. Functional diversity, proportion of shredders and semivoltine invertebrates were significantly higher in reference streams than in the restored stream reaches. We hypothesized that inputs of coarse particulate organic matter and land use at watershed scale may explain the differences in biodiversity between restored and reference stream reaches. Habitat variables did not change from pre‐project to post‐project, so they could not explain community changes. This may have been partly attributable to insensitivity of the visual estimate methods used but likely also reflects the importance of watershed variables on aquatic biota—suggesting watershed actions may be more effective for the ecological recovery of streams. For future projects, we recommend multihabitat benthic sampling supported by studies of channel geomorphology to better understand stream response to restoration actions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
14.
There is a great deal of interest in the literature on streamflow changes caused by climate change because of the potential negative effects on aquatic biota and water supplies. Most previous studies have primarily focused on perennial streams, and there have been only a few studies examining the effect of climate variability on intermittent streams. Our objectives in this study were to (1) identify regions of similar zero‐flow behaviour and (2) evaluate the sensitivity of intermittent streams to historical variability in climate in the USA. This study was carried out at 265 intermittent streams by evaluating (1) correlations among time series of flow metrics (number of zero‐flow events, the average of the central 50% and largest 10% of flows) with climate (magnitudes, durations and intensity) and (2) decadal changes in the seasonality and long‐term trends of these flow metrics. Results identified five distinct seasonality patterns in the zero‐flow events. In addition, strong associations between the low‐flow metrics and historical changes in climate were found. The decadal analysis suggested no significant seasonal shifts or decade‐to‐decade trends in the low‐flow metrics. The lack of trends or changes in seasonality is likely due to unchanged long‐term patterns in precipitation over the time period examined. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
15.
Urbanization and its associated stressors such as flow alteration, channel modification and poor water quality is a leading cause of ecological degradation to rivers and streams. Driven by public concern to address this issue, there has been a dramatic increase in urban restoration projects since 1990 using in‐stream structures. Attempts at restoring the ecological condition of urban streams using structures have produced varied results, but projects do not often meet planned ecological goals. A major challenge to improving the ecological health of urban streams is to better understand how to incorporate ecological assessments into a ‘restoration’ design framework with reasonable expectations for ecological recovery. A naturalization design framework was used in a project on a 0.62‐km reach of the North Branch of the Chicago River in Northbrook, Illinois. Initial surveys of channel morphology, habitat and biota identified poor pool‐riffle bed structure and fish biodiversity, which became the basis for research and development of a pool‐riffle structure specifically designed for constrained, low‐gradient channels. Habitat and fish surveys were conducted pre‐ and post‐construction. The project improved mesohabitat structure, and fish abundance, and biomass and diversity were greater for 2 years following construction (2002–2003) compared to 3 years prior to construction (1999–2001). However, the improved fish metrics were in the low range when compared to rural streams in the same ecoregion, and the fish community consisted primarily of tolerant, slow‐water species. Absent were intolerant and riffle dwelling species, such as insectivorous cyprinids and darters. Assessment of pre‐ and post‐project ecological condition and the use of species information provided a basis for ecologically informed design and expanded our understanding of the limitations to restoring urban streams. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
16.
Heejun Chang Deonie Allen Jennifer Morse Janardan Mainali 《Journal of Flood Risk Management》2019,12(4)
This study investigated the delivery of contaminated sediments to the channel network by urban drainage systems in Johnson Creek in Oregon, USA. Concentrations of five heavy metal concentrations measured in 136 samples collected from 37 stormwater outfalls and 99 bed sampling points were analysed. While concentrations of zinc, cadmium, and lead increased with distance downstream in Johnson Creek, this was not the case for chromium and copper. Zinc, copper, and cadmium concentrations in outfalls were significantly higher than those in the stream bed, indicating that stormwater runoff is responsible for delivering contaminated sediments to Johnson Creek. Zinc concentrations in outfalls were negatively associated with elevation and slope in the contributing subcatchment, and positively with impervious cover. However, no statistically significant relationships were found between the other heavy metal concentrations and subcatchment variables. These findings demonstrate that relationships between sediment‐related, heavy metal concentrations, and subcatchment characteristics in this heterogeneous, rural–urban catchment are more complex than those found in situations where land‐use is more segregated, questioning the applicability of commonly held assumptions regarding changes in the sources and delivery paths of flood‐related, sediment‐associated pollutants that accompany urbanisation. 相似文献
17.
Increased fine sediment deposition and entrainment in rivers can arise from a combination of factors including low flows, habitat modification and excessive sediment delivery from the catchment. Physical and visual methods have traditionally been used to quantify the volume of deposited fine sediment (<2 mm in size), but here we propose an alternative, the development and utilization of a sediment‐sensitive macro‐invertebrate metric (PSI — Proportion of Sediment‐sensitive Invertebrates) which provides a proxy to describe the extent to which the surface of river beds are composed of, or covered by, fine sediments. Where suitable biomonitoring data exists, the index can be calculated retrospectively to track trends in fine sediment deposition, and its ecological impact, through time. Furthermore, the utilization of reference condition models such as RIVPACS (River InVertebrate Prediction And Classification System), allows site‐specific unimpacted conditions to be defined, opening‐up the possibility of standard classification and assessment systems being developed. In Europe, such systems are vital if the Water Framework Directive is to be implemented. Knowledge regarding spatial differences in sediment/flow interdependencies may provide valuable information on diffuse sources of fine sediment to rivers and we illustrate this with an example from the UK (Laceby Beck). Further UK case studies are presented to show a range of applications, including the demonstration of improvements in habitat heterogeneity following river restoration (rivers Chess and Rib) and the detection of fine sediment impacts downstream of an impoundment (Eye Brook). The PSI metric offers a readily deployable, cost‐effective and hydroecologically relevant methodology for the assessment of fine sediment impacts in rivers. The technique has potential for application outside of the UK and an adaptation of the methodology for use in the Simandou Mountains (Guinea) is used to illustrate this. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
18.
Conversion of high mountain forests into pastures or croplands and changes in land uses have produced changes in hydrology, vegetation cover and terrestrial aquatic linkages, resulting in increased nutrient loads on water bodies. The developing countries today need to obtain an indicator response signature under multiple stressor scenario, to identify causes of water bodies impairment. Intermountain land use impact on a Subtropical Andean River was studied in Tucumán province, Northwestern Argentina. Benthic macroinvertebrates were used as indicators of diffuse alterations produced by anthropic activities on a small valley at ca. 1000 m.a.s.l. The objectives were: (a) test the effect of land use on macroinvertebrate assemblages; (b) test the response of benthic fauna to diffuse organic pollution and (c) test the accuracy of the current biological water quality indices. Nutrient levels were higher than international standards. First axis in multivariate analysis shows an important upstream–downstream gradient meanwhile the second axis shows seasonal effects. These effects are specially produced by monsoonal regime of rainfall (ca. 80% in summer). No effect of the land use or diffuse pollution was detected on the macroinvertebrate assemblage structure, probably due to the good oxygen availability. Of the several biotic indices (BI) and metrics tested, only one worked on acceptable levels being ‘affected’ by small oxygen variations. Dry winter, dry and warm spring with high sunlight exposure plus high levels of nutrients could be an undesirable combination for standing waters of a reservoir projected in this watershed. A correct monitoring of water quality and alternatives as management of reforested margins is the right beginning. These actions and more studies represent interesting alternatives for poor regions of undeveloped countries. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
19.
赵全举 《广东水利电力职业技术学院学报》2006,4(2):35-38
以地表堆积物中的Pb、Zn、Cu、Cd作为重点研究对象,在广州市分三个功能区(工业区、商业区、住宅区)进行地表堆积物样品的采集,从总含量、不同粒径级含量来分析堆积物中重金属的总体特性,并以研究结论为广州城市非点源的防治与管理提供理论依据。 相似文献