30 results on '"Lemm, J.U."'
Search Results
2. Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems
- Author
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Birk, S., Chapman, D., Carvalho, L., Spears, B.M., Andersen, H.E., Argillier, C., Auer, S., Baattrup-Pedersen, A., Banin, L., Beklioglu, M., Bondar-Kunze, E., Borja, A., Branco, P., Bucak, T., Buijse, A.D., Cardoso, A.C., Couture, R.M., Cremona, F., Zwart, D. de, Feld, C.K., Ferreira, M.T., Feuchtmayr, H., Gessner, M.O., Gieswein, A., Globevnik, L., Graeber, D., Graf, W., Gutiérrez-Cánovas, C., Hanganu, J., Iskin, U., Järvinen, M., Jeppesen, E., Kotamäki, N., Kuijper, M., Lemm, J.U., Lu, S., Solheim, A.L., Mischke, U., Moe, S.J., Noges, P., Noges, T., Ormerod, S.J., Panagopoulos, Y., Phillips, G., Posthuma, L., Pouso, S., Prudhomme, C., Rankinen, K., Rasmussen, J.J., Richardson, J., Sagouis, A., Santos, J.M., Schäfer, R.B., Schinegger, R., Schmutz, S., Schneider, S.C., Schülting, L., Segurado, P., Stefanidis, K., Sures, B., Thackeray, S.J., Turunen, J., Uyarra, M.C., Venohr, M., Ohe, P.C. von der, Willby, N., Hering, D., Birk, S., Chapman, D., Carvalho, L., Spears, B.M., Andersen, H.E., Argillier, C., Auer, S., Baattrup-Pedersen, A., Banin, L., Beklioglu, M., Bondar-Kunze, E., Borja, A., Branco, P., Bucak, T., Buijse, A.D., Cardoso, A.C., Couture, R.M., Cremona, F., Zwart, D. de, Feld, C.K., Ferreira, M.T., Feuchtmayr, H., Gessner, M.O., Gieswein, A., Globevnik, L., Graeber, D., Graf, W., Gutiérrez-Cánovas, C., Hanganu, J., Iskin, U., Järvinen, M., Jeppesen, E., Kotamäki, N., Kuijper, M., Lemm, J.U., Lu, S., Solheim, A.L., Mischke, U., Moe, S.J., Noges, P., Noges, T., Ormerod, S.J., Panagopoulos, Y., Phillips, G., Posthuma, L., Pouso, S., Prudhomme, C., Rankinen, K., Rasmussen, J.J., Richardson, J., Sagouis, A., Santos, J.M., Schäfer, R.B., Schinegger, R., Schmutz, S., Schneider, S.C., Schülting, L., Segurado, P., Stefanidis, K., Sures, B., Thackeray, S.J., Turunen, J., Uyarra, M.C., Venohr, M., Ohe, P.C. von der, Willby, N., and Hering, D.
- Abstract
Contains fulltext : 228877pub.pdf (Publisher’s version ) (Closed access) Contains fulltext : 228877pos.pdf (Author’s version postprint ) (Open Access)
- Published
- 2020
3. Identification of Individuals of Two Takin Subspecies Using Biological and Ecological Criteria in Eastern Himalayas of China.
- Author
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Wang, Yuan, Lv, Yonglei, Wang, Guanglong, Liu, Feng, Ji, Yingxun, Liu, Zheng, Zhao, Wanglin, Liu, Wulin, Dun Zhu, Pu Bu, and Jin, Kun
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ANIMAL diversity ,ECOLOGICAL surveys ,ENDANGERED species ,MOUNTAIN ecology ,ECOLOGICAL models - Abstract
Simple Summary: Takins in the Eastern Himalayas of China are very diverse; however, species research in this region is lacking. Therefore, limited background data are available on the different subspecies present in this region. Using ecological models and surveys, this study examined the factors of two subspecies in this region, including phenotypic characteristics, population, activity, and distribution range, to provide species identification and classification references. The results revealed that the Mishmi takin and Bhutan takin could be differentiated using camera trapping. Their distribution areas, population densities, and population sizes could be determined in all human-accessible areas of the Eastern Himalayas in China. Thus, this study contributes to basic animal diversity knowledge and provides detailed information and references for species identification, distribution ranges, and population characteristics of the Mishmi and Bhutan takins. Moreover, this study provides resource data for subspecies classification that can be used to promote effective protection measures for endangered species. Limited background data are available on the Mishmi takin (Budorcas taxicolor taxicolor) and Bhutan takin (Budorcas taxicolor whitei) subspecies in the Eastern Himalayas of China because of the lack of systematic field investigations and research. Therefore, mature-animal ecological methods were used to evaluate these takin subspecies' phenotypic characteristics, distribution range, activity rhythm, and population size. From 2013 to 2022, 214 camera traps were installed for wild ungulate monitoring and investigation in all human-accessible areas of the Eastern Himalayas, resulting in 4837 distinguishable takin photographs. The external morphological characteristics were described and compared using visual data. Artificial image correction and related technologies were used to establish physical image models based on the differences between subspecies. MaxEnt niche and random encounter models obtained distribution ranges and population densities. Mishmi takins have a distribution area of 17,314 km
2 , population density of 0.1729 ± 0.0134 takins/km2 , and population size of 2995 ± 232. Bhutan takins have a distribution area of 25,006 km2 , population density of 0.1359 ± 0.0264 takins/km2 , and population size of 3398 ± 660. Long-term monitoring data confirmed that the vertical migration within the mountain ecosystems is influenced by climate. Mishmi takins are active at 500–4500 m, whereas Bhutan takins are active at 1500–4500 m. The two subspecies were active at >3500 m from May to October yearly (rainy season). In addition, surveying combined with model simulation shows that the Yarlung Zangbo River is not an obstacle to migration. This study provides basic data that contribute to animal diversity knowledge in biodiversity hotspots of the Eastern Himalayas and detailed information and references for species identification, distribution range, and population characteristics. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Exploring the Response of Ecosystem Services to Socioecological Factors in the Yangtze River Economic Belt, China.
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Zhang, Zhiming, Fang, Fengman, Yao, Youru, Ji, Qing, and Cheng, Xiaojing
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ECOSYSTEM services ,ECOSYSTEM management ,RANDOM matrices ,RANDOM forest algorithms ,RESTORATION ecology ,SEX ratio - Abstract
Understanding the response of the mechanisms driving ecosystem services (ESs) to socioecological factors is imperative for regional sustainable ecosystem management. However, previous studies of the mechanisms driving ESs have focused more on the degree and direction (positive and negative) of effects on ES supply or the supply–demand balance, while their nonlinear response processes have not been fully considered. In this study, a theoretical framework was developed through integrating land use/land cover data and supply and demand matrices with random forest models to assess response processes, including the relative importance and marginal effects, of essential factors that drive ES demand, supply, and supply–demand balance. Using the Yangtze River Economic Belt (YREB) as an example, our results indicated that the ES deficit regions (332 of 1070 counties or 14.45% of the area) of the YREB were located mainly in the three national urban agglomerations. Moreover, this study indicated that natural environmental factors (such as slope and precipitation) significantly influence the supply and supply–demand balance of ESs, while socioeconomic factors (such as cropland ratios and population density) profoundly influence the demand for ESs. However, cropland ratios were the most important drivers of ES supply, demand, and supply–demand balance in the YREB. Moreover, three types of response processes were identified in this study: logarithmic increase, logarithmic decrease, and volatility increase. Specific driving factors (e.g., proportion of cropland area, precipitation, population density, and slope) had significant threshold effects on the supply–demand balance of ESs. The turning points that can be extracted from these response processes should be recommended for ecosystem restoration projects to maintain regional sustainable ecosystem management. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Forecasting and Anomaly Detection in BEWS: Comparative Study of Theta, Croston, and Prophet Algorithms.
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Grekov, Aleksandr N., Vyshkvarkova, Elena V., and Mavrin, Aleksandr S.
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ANOMALY detection (Computer security) ,WATER management ,WATER pollution ,ALGORITHMS ,WATER quality - Abstract
Evaluation of water quality and accurate prediction of water pollution indicators are key components in water resource management and water pollution control. The use of biological early warning systems (BEWS), in which living organisms are used as biosensors, allows for a comprehensive assessment of the aquatic environment state and a timely response in the event of an emergency. In this paper, we examine three machine learning algorithms (Theta, Croston and Prophet) to forecast bivalves' activity data obtained from the BEWS developed by the authors. An algorithm for anomalies detection in bivalves' activity data was developed. Our results showed that for one of the anomalies, Prophet was the best method, and for the other two, the anomaly detection time did not differ between the methods. A comparison of methods in terms of computational speed showed the advantage of the Croston method. This anomaly detection algorithm can be effectively incorporated into the software of biological early warning systems, facilitating rapid responses to changes in the aquatic environment. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Landscape Changes in the Bavarian Foothills since the 1960s and the Effects on Predicted Erosion Processes and Control.
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Höfler, Sarah, Ringler, Gerald, Gumpinger, Clemens, Reebs, Felix, Schnell, Johannes, and Hauer, Christoph
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EROSION ,UNIVERSAL soil loss equation ,CLIMATE change ,LANDSCAPE changes ,SOIL erosion ,FOOTHILLS - Abstract
Socio-economic changes, technical progress, and a variety of funding and planning interventions have significantly changed land use in Central Europe since World War II. The aim of this study was to illustrate these changes in the Alpine foothills in Bavaria and to calculate the effects of these changes on soil erosion. This was performed in a two-step procedure: a GIS-based orthophoto evaluation and a cause–effect model using the revised universal soil loss equation (RUSLE). Key findings were that field sizes (+370%) and lengths (+35%) have changed significantly since the 1960s. Moreover, the uninterrupted runoff paths on arable land have increased in length by about 70% on average, with corresponding effects on soil erosion. The discussion shows that the possibilities for erosion control measures in the field are already severely limited due to the effects of the climate crisis and structural changes in agriculture. Furthermore, the often-assumed rule, according to which only a small part of the arable land causes a large share of the eroded material, was largely confirmed. The findings underline the overlapping impacts of land use change and climate crisis on agriculture erosions rates with the need for integrative and adaptive management. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Effects of Land Use Characteristics, Physiochemical Variables, and River Connectivity on Fish Assemblages in a Lowland Basin.
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Zhang, Zhiming, Gao, Junfeng, and Cai, Yongjiu
- Abstract
Human disturbances can have severe environmental impacts on freshwater ecosystems. The main aim of this study is to detect the influences of physiochemical variables, land-cover characteristics, and river connectivity on fish assemblages in the Lake Chaohu Basin, China. A cluster analysis of river connectivity variables identified four groups of sites characterized by significantly different connectivity gradients at a local scale. These four groups of sites showed increasing connectivity from the upper reaches to the lower reaches. At the same time, among the four groups, the values of environmental variables generally increased from the upper reaches with less human activities towards the lower reaches with more human activities. For instance, some main physiochemical variables (e.g., river width, water depth, nitrate, phosphate) significantly increased among the four groups. In contrast, fish taxa richness and diversity indices were not significantly different among the four connectivity groups. However, fish assemblages showed significant variations among the connectivity groups (p = 0.026). In addition, the study determined that upper riparian land uses (e.g., woodland and grassland), flow velocity, and elevation were environmental variables regulating the variance of fish communities. As for the connectivity variables, only river order and the number of branches along a path to the left of the main stem affected the variance of fish communities. Therefore, new practices aimed at maintaining and even increasing riparian canopy coverage and the flow velocity of rivers should be integrated into local conservation planning for freshwater ecosystems, especially in the upper reaches of the basin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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8. Simulating Phosphorus Load Reductions in a Nested Catchment Using a Flow Pathway-Based Modeling Approach.
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Adams, Russell and Quinn, Paul
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WATER management ,WATERSHEDS ,WATER quality ,PHOSPHORUS ,RUNOFF - Abstract
Catchment models are essential tools to identify and predict water quality problems linked to excessive nutrient applications (in this case phosphorus (P)). The Catchment Runoff Attenuation Flux Tool (CRAFT) has been successfully used to model nutrient fluxes and concentrations in north-western European catchments. The model is extremely parsimonious due to the relatively small number of parameters. However, an improvement to the representation of soluble P and particulate P fluxes in the fast-subsurface and surface runoff flow pathways was required. A case study in the north of Ireland applied the original and the new, enhanced (Dynamic) version of the CRAFT to the trans-border Blackwater catchment (UK and Republic of Ireland) covering nearly 1500 km
2 , with the land use predominantly livestock grazing. The larger size of the Blackwater also required a nested modeling approach to be implemented using a multiple sub-catchment variant (MultiCRAFT). P load reductions in the different sub-catchments were first identified using a simple approach based on the gap between the Water Framework Directive (WFD) limits for "Good" ecological status for soluble reactive P (SRP) concentrations and the recently observed concentrations. Modeling of different mitigation scenarios was then conducted using the MultiCRAFT framework with the best-performing variant of the CRAFT model embedded. The catchment was found to have flashy, episodic delivery of high concentrations of SRP and PP during runoff events which will require different sources (i.e., diffuse and point) of P to be targeted to achieve the WFD targets by the end of the decade. The modeling results thus showed that the required SRP load reductions could be best achieved using a combined scenario of mitigation measures that targeted diffuse sources contributing to both the surface runoff and fast-subsurface flow pathways, with point sources also identified as needing reduction in some sub-catchments. [ABSTRACT FROM AUTHOR]- Published
- 2023
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9. Eukaryotes contribute more than bacteria to the recovery of freshwater ecosystem functions under different drought durations.
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Li, Chaoran, Miao, Lingzhan, Adyel, Tanveer M., Huang, Wei, Wang, Jianjun, Wu, Jun, Hou, Jun, and Wang, Zhiyuan
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DROUGHTS ,DROUGHT management ,EXTREME weather ,EPHEMERAL streams ,RIVER channels ,CLIMATE change ,ECOSYSTEMS - Abstract
Global climate change mostly impacts river ecosystems by affecting microbial biodiversity and ecological functions. Considering the high functional redundancy of microorganisms, the unknown relationship between biodiversity and ecosystem functions obstructs river ecological research, especially under the influence of increasing weather extremes, such as in intermittent rivers and ephemeral streams (IRES). Herein, dry–wet alternation experiments were conducted in artificial stream channels for 25 and 90 days of drought, both followed by 20 days of rewetting. The dynamic recovery of microbial biodiversity and ecosystem functions (represented by ecosystem metabolism and denitrification rate) were determined to analyse biodiversity–ecosystem–function (BEF) relationships after different drought durations. There was a significant difference between bacterial and eukaryotic biodiversity recovery after drought. Eukaryotic biodiversity was more sensitive to drought duration than bacterial, and the eukaryotic network was more stable under dry–wet alternations. Based on the establishment of partial least squares path models, we found that eukaryotic biodiversity has a stronger effect on ecosystem functions than bacteria after long‐term drought. Indeed, this work represents a significant step forward for further research on the ecosystem functions of IRES, especially emphasizing the importance of eukaryotic biodiversity in the BEF relationship. [ABSTRACT FROM AUTHOR]
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- 2023
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10. Drivers of the Structure of Mollusc Communities in the Natural Aquatic Habitats along the Valley of a Lowland River: Implications for Their Conservation through the Buffer Zones.
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Lewin, Iga, Stępień, Edyta, Szlauer-Łukaszewska, Agnieszka, Pakulnicka, Joanna, Stryjecki, Robert, Pešić, Vladimir, Bańkowska, Aleksandra, Szućko-Kociuba, Izabela, Michoński, Grzegorz, Krzynówek, Zuzanna, Krakowiak, Maja, Chatterjee, Tapas, and Zawal, Andrzej
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RIVER conservation ,AQUATIC habitats ,BIOTIC communities ,MOLLUSKS ,CONSERVATION of natural resources ,HABITATS ,FISH communities - Abstract
The objectives of our survey were to determine the most important environmental factors within buffer zones that influenced mollusc communities and to evaluate the ecological conservation value of natural aquatic habitats (NAHs) that support mollusc species. Analysis of the spatial structure of buffer zones and catchments was based on a set of landscape metrics. Land cover classes were determined, and buffer zones within a radius of 500 m from a sampling point were marked out. Mollusc samples were collected from each NAHs. Our results showed that the number of patches and mean patch size were most associated with the distribution of mollusc species. Within patches of buffer zones, the length of the catchment boundaries with low-density housing, an increasing area of forest and pH of the water were also significant. Our results proved that landscape metrics provide essential information about catchment anthropogenic transformation. Therefore, landscape metrics and the designated buffer zones should be included in restoration plans for the river, water bodies and adjacent habitats as elements of modern, sustainable water management. NAHs located along a valley of a lowland river provide refuges for molluscs, play an essential role in the dispersal of IAS, create important protective biogeochemical barriers for rivers, constitute necessary sources of moisture and water and support microhabitats for distinct mollusc communities, especially in the context of global warming. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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11. Microplastic Contamination and Ecological Status of Freshwater Ecosystems: A Case Study in Two Northern Portuguese Rivers.
- Author
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Ribeiro, Andreia, Gravato, Carlos, Cardoso, João, Ribeiro, Carlos Alexandre, Vieira, Maria Natividade, and Rodrigues, Carolina
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- 2022
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12. Response of Chironomids to Key Environmental Factors: Perspective for Biomonitoring.
- Author
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Rossaro, Bruno, Marziali, Laura, and Boggero, Angela
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BIOLOGICAL monitoring ,ENVIRONMENTAL indicators ,WATER quality ,RELATIONAL databases ,BIOINDICATORS ,ENVIRONMENTAL quality ,CRONBACH'S alpha - Abstract
Simple Summary: Benthic macroinvertebrates of inland waters, including running waters and lakes, are frequently used in biomonitoring. Sometimes, environmental data associated with species lists are not available; in this situation traits or functional adaptations of species to environment can be considered as a tool to translate the list of species into a useful index to evaluate the environmental quality a body of water. Chironomids are the species-richest family among macroinvertebrates and are often used as indicators of ecological conditions in inland waters. High taxonomic expertise is needed for identification and new species are still being described even in the well-known West Palearctic region. Our Microsoft Access relational database comprises data on Chironomid species collected in rivers and lakes in Italy and some other European countries over a period of about 50 years, often associated with physical-chemical data, but in some cases, only data on Chironomids are available with no associated environmental data. The aim of the present paper was to propose the calculation of ecological traits of Chironomid species as a tool to derive information on water quality, when only data on Chironomid species composition are present, while environmental data are lacking. Traits summarizing the species' response to environmental variables were evaluated, with emphasis on natural and man-influenced factors: current velocity, water temperature, conductivity, dissolved oxygen, and nutrients. Traits calculations were carried out in the R environment using a subset of our data, including both environmental data and Chironomid abundances. The relations between sites, Chironomid, species and traits were evaluated using correspondence analysis and other multivariate methods. The response of species showed an interaction among different factors, with the possibility of ordering species along a single environmental gradient, extending from cold running waters to warm standing waters, with few exceptions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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13. Ecological Quality Assessment of Greek Lowland Rivers with Aquatic Macrophytes in Compliance with the EU Water Framework Directive.
- Author
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Stefanidis, Konstantinos, Dimitrellos, Georgios, Sarika, Maria, Tsoukalas, Dionysios, and Papastergiadou, Eva
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WATER management ,ECOLOGICAL assessment ,ENVIRONMENTAL monitoring ,MACROPHYTES ,AQUATIC plants ,MULTIVARIATE analysis - Abstract
Aquatic macrophytes are one of the four biological quality elements (BQE) used for assessing the ecological status of inland waters according to the EU Water Framework Directive (WFD 2000/60). With this article, we present the methodological approach for the implementation of a WFD compliant macrophyte index to the riverine systems of Greece. In addition to the definition and harmonization of the ecological quality class boundaries, the results from the pilot application of the index and the ecological classification of the monitored river reaches are also presented. Aquatic plants and environmental parameters were sampled from 93 river reaches between 2012 and 2015. A multivariate analysis with optimal scaling (MVAOS) was conducted to define the main stressor gradient and to identify the least disturbed sites and the reference conditions that are required for the derivation of the ecological quality classes. The Macrophyte Biological Index IBMR for Greek rivers (IBMR
GR ) was calculated for all the sites and the boundaries for the five quality classes were derived according to the methodology proposed by the Mediterranean Geographic Intercalibration Group (MedGIG). The main findings showed that the hydromorphological modifications were the main environmental stressors that correlated strongly with the IBMRGR , whereas physicochemical stressors were of lesser importance. More specifically, the first principal component explained 51% of the total variance of the data, representing a moderately strong gradient of hydromorphological stress, whereas the second component explained 22.5%, representing a weaker gradient of physicochemical stress. In addition, the ecological assessment showed that almost 60% of the sites failed the WFD target of the "Good" ecological quality class, which agrees with classification assessments based on other BQEs for Greece and many Mediterranean countries. Overall, this work provides a first assessment of the ecological classification of Greek rivers with the BQE of aquatic macrophytes with significant implications for ecological monitoring and decision making within the frame of the WFD implementation. [ABSTRACT FROM AUTHOR]- Published
- 2022
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14. A Simple Index of Lake Ecosystem Health Based on Species-Area Models of Macrobenthos.
- Author
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Wu, Junyan, He, Yajing, Zhao, Yongjing, Chen, Kai, Cui, Yongde, and Wang, Hongzhu
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- 2022
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15. Ecological River Health Assessment Using Multi-Metric Models in an Asian Temperate Region with Land Use/Land Cover as the Primary Factor Regulating Nutrients, Organic Matter, and Fish Composition.
- Author
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Mamun, Md, Jargal, Namsrai, Atique, Usman, and An, Kwang-Guk
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- 2022
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16. A Comparative Evaluation of Hydromorphological Assessment Methods Applied in Rivers of Greece.
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Stefanidis, Konstantinos, Kouvarda, Theodora, Latsiou, Anna, Papaioannou, George, Gritzalis, Konstantinos, and Dimitriou, Elias
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WATER management ,ECOLOGICAL assessment ,BIOLOGICAL monitoring ,BODIES of water - Abstract
The ecological assessment of all surface water bodies in Europe according to the Water Framework Directive involves the monitoring of biological, physicochemical and hydromorphological quality elements. For the hydromorphological assessment in particular, there are numerous methods that have been developed and adopted by EU member countries. With this study, we compared three different methods (River Habitat Survey, Morphological Quality Index and River Hydromorphology Assessment Technique) applied in 122 river reaches that are part of the National Monitoring Network of Greece. The main objectives were (a) to identify whether different assessment systems provide similar classifications of hydromorphological status and (b) to distinguish strengths and weaknesses associated with the implementation of each method. Our results show that the River Hydromorphology Assessment Technique (RHAT) and the Morphological Quality Index (MQI) resulted in the same classification for 58% of the studied reaches, while 34% of the remaining cases differed by only one quality class. Correlations between the two indices per river type (ICT) showed that the two indices were strongly correlated for water courses located at low altitudes. Concerning the HMS index of the River Habitat Survey (RHS), which is an index that reflects the overall hydromorphological pressure, it showed larger differences with the other two indices, mainly because it classified more sites as "Poor" and "Bad" quality classes. Based on our results, we recommend that the two indices, RHAT and MQI, can be implemented complementary to the RHS for providing a rather easy and quick assessment of the overall hydromorphological status, at least until a national hydromorphological database is compiled that will allow for the proper adaptation of the Habitat Quality Assessment (HQA) index. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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17. A river classification scheme to assess macroinvertebrate sensitivity to water abstraction pressures.
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Lathouri, Maria, England, Judy, Dunbar, Michael J., Hannah, David M., and Klaar, Megan
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WATER pressure ,STREAMFLOW ,BIOINDICATORS ,MULTILEVEL models ,CLASSIFICATION - Abstract
The concept of environmental flows has been developed to manage human alteration of river flow regimes, as effective management requires an understanding of the ecological consequences of flow alteration. This study explores the concept of macroinvertebrate sensitivity to river flow alteration to establish robust quantitative relationships between biological indicators and hydrological pressures. Existing environmental flow classifications used by the environmental regulator for English rivers were tested using multilevel regression modelling. Results showed a weak relationship between the current abstraction sensitivity classification and macroinvertebrate response to flow pressure. An alternative approach, based on physically derived river types, was a better predictor of macroinvertebrate response. Intermediate sized lowland streams displayed the best model fit, while upland rivers exhibited poor model performance. A better understanding of the ecological response to flow variation in different river types could help water resource managers develop improved ecologically appropriate flow regimes, which support the integrity of river ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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18. Effects of multiple stressors on the dimensionality of ecological stability.
- Author
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Polazzo, Francesco, Rico, Andreu, and Isbell, Forest
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ECOLOGICAL disturbances ,INSECTICIDES ,HERBICIDES ,HERBICIDE resistance ,BIOTIC communities ,PESTICIDES - Abstract
Ecological stability is a multidimensional construct. Investigating multiple stability dimensions is key to understand how ecosystems respond to disturbance. Here, we evaluated the single and combined effects of common agricultural stressors (insecticide, herbicide and nutrients) on four dimensions of stability (resistance, resilience, recovery and invariability) and on the overall dimensionality of stability (DS) using the results of a freshwater mesocosm experiment. Functional recovery and resilience to pesticides were enhanced in nutrient‐enriched systems, whereas compositional recovery was generally not achieved. Pesticides did not affect compositional DS, whereas functional DS was significantly increased by the insecticide only in non‐enriched systems. Stressor interactions acted non‐additively on single stability dimensions as well as on functional DS. Moreover we demonstrate that pesticides can modify the correlation between functional and compositional aspects of stability. Our study shows that different disturbance types, and their interactions, require specific management actions to promote ecosystem stability. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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19. Assessing the Ecological Status of European Rivers and Lakes Using Benthic Invertebrate Communities: A Practical Catalogue of Metrics and Methods.
- Author
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Vitecek, Simon, Johnson, Richard K., and Poikane, Sandra
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INVERTEBRATE communities ,WATER management ,ECOSYSTEM management ,HUMAN settlements ,ECOLOGICAL assessment - Abstract
The Water Framework Directive requires that the ecological status of surface waters be monitored and managed if necessary. A central function in ecological status assessment has the Biological Quality Elements—organisms inhabiting surface waters—by indicating human impact on their habitat. For benthic invertebrates, a wide array of national methods are used, but to date no comprehensive summary of metrics and methods is available. In this study, we summarize the benthic invertebrate community metrics used in national systems to assess the ecological status of rivers, (very) large rivers, and lakes. Currently, benthic invertebrate assemblages are used in 26 national assessment systems for rivers, 13 assessment systems for very large rivers, and 21 assessment systems for lakes in the EU. In the majority of systems, the same metrics and modules are used. In the Red Queen's race of ecosystem management this may be a disadvantage as these same metrics and module likely depict the same stressors but there is growing evidence that aquatic ecosystems are subject to highly differentiated, complex multiple stressor impacts. Method development should be fostered to identify and rank impacts in multi-stressor environments. DNA-based biomonitoring 2.0 offers to detect stressors with greater accuracy—if new tools are calibrated. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Use of Monitoring Approaches to Verify the Predictive Accuracy of the Modeling of Particle-Bound Solid Inputs to Surface Waters.
- Author
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Allion, Katharina, Gebel, Michael, Uhlig, Mario, Halbfass, Stefan, Bürger, Stephan, Kiemle, Lisa, and Fuchs, Stephan
- Subjects
PREDICTION models ,BODIES of water ,SPATIAL resolution ,SOIL moisture ,SEDIMENTS ,SOIL erosion - Abstract
For particle-bound substances such as phosphorus, erosion is an important input pathway to surface waters. Therefore, knowledge of soil erosion by water and sediment inputs to water bodies at high spatial resolution is essential to derive mitigation measures at the regional scale. Models are used to calculate soil erosion and associated sediment inputs to estimate the resulting loads. However, validation of these models is often not sufficiently possible. In this study, sediment input was modeled on a 10 × 10 m grid for a subcatchment of the Kraichbach river in Baden-Wuerttemberg (Germany). In parallel, large-volume samplers (LVS) were operated at the catchment outlet, which allowed a plausibility check of the modeled sediment inputs. The LVS produced long-term composite samples (2 to 4 weeks) over a period of 4 years. The comparison shows a very good agreement between the modeled and measured sediment loads. In addition, the monitoring concept of the LVS offers the possibility to identify the sources of the sediment inputs to the water body. In the case of the Kraichbach river, it was found that around 67% of the annual sediment load in the water body is contributed by rainfall events and up to 33% represents dry-weather load. This study shows that the modeling approaches for calculating the sediment input provide good results for the test area Kraichbach and the transfer for a German wide modeling will produce plausible values. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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21. Assessing the Effects of Multiple Stressors on Aquatic Systems across Temporal and Spatial Scales: From Measurement to Management.
- Author
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Segurado, Pedro, Ferreira, Teresa, and Branco, Paulo
- Subjects
ECOSYSTEM services ,FRESHWATER biodiversity ,LIFE sciences ,SCALING (Social sciences) ,WATER management ,ECOLOGICAL integrity ,INVERTEBRATE communities ,RANGE management - Abstract
10.3390/w12030621 20 Lange K., Townsend C., Matthaei C. Inconsistent Relationships of Primary Consumer N Stable Isotope Values to Gradients of Sheep/Beef Farming Intensity and Flow Reduction in Streams. In contrast, the SB 15 sb N of the two analyzed snail species either showed a positive response to farming intensity ( I Physella i spp.) or no significant response ( I Potamopyrgus i spp.). These habitats have long been affected by a wide range of co-occurring environmental stressors that disrupt freshwater biodiversity and ecosystem functioning, hence menacing the provision of ecosystem services that are vital to human well-being, including water supply and food security [[2], [4]]. Freshwater habitats are home to a disproportionately high biodiversity, given the total area they cover worldwide, hosting 10% of all species while occupying less than 1% of the Earth's surface [[1]]. [Extracted from the article]
- Published
- 2021
- Full Text
- View/download PDF
22. Anthropogenic Stressors in Upland Rivers: Aquatic Macrophyte Responses. A Case Study from Bulgaria.
- Author
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Gecheva, Gana, Pall, Karin, Todorov, Milcho, Traykov, Ivan, Gribacheva, Nikolina, Stankova, Silviya, and Birk, Sebastian
- Subjects
UPLANDS ,VASCULAR plants ,MACROPHYTES ,AQUATIC plants ,SPECIES diversity - Abstract
Upland rivers across Europe still exhibit undisturbed conditions and represent a treasure that we cannot afford to lose. We hypothesize that the combination of pristine and modified conditions could demonstrate biological responses along the stressor gradients. Thus, the response of aquatic macrophyte communities to anthropogenic stressors along upland rivers in Bulgaria was studied. Six stressors were selected out of 36 parameters grouped into hydromorphological, chemical variables and combined drivers (catchment land use). The stressors strongly affected species richness on the basis of biological type (bryophytes vs. vascular plants) and ecomorphological type (hydrophytes vs. helophytes). Hydrological alteration expressed by the change of the river's base flow and altered riparian habitats has led to a suppression of bryophytes and a dominance of riverbank plant communities. Seventy-five percent of mountain sites were lacking bryophytes, and the vegetation at semi-mountainous sites was dominated by vascular plants. It can be concluded that hydropeaking, organic and inorganic pollution, and discontinuous urban structures caused important modifications in the aquatic macrophyte assemblages. Macrophyte abundance and the biological and ecomorphological type of aquatic macrophytes reflect multi-stressor effects in upland rivers. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Best Practices for Monitoring and Assessing the Ecological Response to River Restoration.
- Author
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England, Judy, Angelopoulos, Natalie, Cooksley, Susan, Dodd, Jennifer, Gill, Andrew, Gilvear, David, Johnson, Matthew, Naura, Marc, O'Hare, Matthew, Tree, Angus, Wheeldon, Jennifer, and Wilkes, Martin A.
- Subjects
ENVIRONMENTAL monitoring ,RESTORATION ecology ,BEST practices ,STREAM restoration ,CONSERVATION & restoration ,BIOTIC communities ,FRESHWATER biodiversity - Abstract
Nature-based solutions are widely advocated for freshwater ecosystem conservation and restoration. As increasing amounts of river restoration are undertaken, the need to understand the ecological response to different measures and where measures are best applied becomes more pressing. It is essential that appraisal methods follow a sound scientific approach. Here, experienced restoration appraisal experts review current best practice and academic knowledge to make recommendations and provide guidance that will enable practitioners to gather and analyse meaningful data, using scientific rigor to appraise restoration success. What should be monitored depends on the river type and the type and scale of intervention. By understanding how habitats are likely to change we can anticipate what species, life stages, and communities are likely to be affected. Monitoring should therefore be integrated and include both environmental/habitat and biota assessments. A robust scientific approach to monitoring and appraisal is resource intensive. We recommend that appraisal efforts be directed to where they will provide the greatest evidence, including 'flagship' restoration schemes for detailed long-term monitoring. Such an approach will provide the evidence needed to understand which restoration measures work where and ensure that they can be applied with confidence elsewhere. [ABSTRACT FROM AUTHOR]
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- 2021
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- View/download PDF
24. Do Water Bodies Show Better Ecological Status in Natura 2000 Protected Areas Than Non-Protected Ones?—The Case of Greece.
- Author
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Stefanidis, Konstantinos, Oikonomou, Anthi, Stoumboudi, Maria, Dimitriou, Elias, and Skoulikidis, Nikolaos Theodor
- Subjects
WATER management ,PROTECTED areas ,BODIES of water ,HABITAT conservation ,LOGISTIC regression analysis ,BIRD habitats - Abstract
Regardless of the efforts of the European Union, freshwaters are in a state of environmental crisis. The Water Framework Directive has established a basis for the protection and restoration of European inland and coastal waters. In parallel, the Birds and Habitats Directives protect, maintain or restore, at favourable conservation status, selected species and habitats under a representative network of protected areas. Hence, the interplay between the EU regulations is of high scientific interest and practical relevance. In this article, Greece is used as a case study to explore whether anticipated synergies between the Water Framework Directive and the Nature Directives result in a better ecological status in the protected areas than in the non-protected ones. We investigated whether the ecological qualities that are defined by three biological quality elements (BQEs) differ between the WFD monitoring sites that are located within the Natura 2000 protected areas and those that are not. We identified a total of 148 river monitoring sites that are located within the Natura 2000 network, which corresponds to 30% of the WFD monitoring network. By employing ordered logit models for each BQE, we found that the ecological quality has the same likelihood to fail the WFD target of "good" quality for sites that are located within and outside the Natura 2000 protected areas. Our results confirmed our hypothesis that the EU directives have little synergy when it comes to restoration of ecological status of Greek running waters, according to the WFD. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
25. Applying Optimization to Support Adaptive Water Management of Rivers.
- Author
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Derepasko, Diana, Peñas, Francisco J., Barquín, José, Volk, Martin, and Hassanzadeh, Elmira
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WATER management ,ADAPTIVE natural resource management ,WATER diversion ,HYDROLOGIC cycle ,INSTREAM flow ,DECISION making - Abstract
Adaptive water management is a promising management paradigm for rivers that addresses the uncertainty of decision consequences. However, its implementation into current practice is still a challenge. An optimization assessment can be framed within the adaptive management cycle allowing the definition of environmental flows (e-flows) in a suitable format for decision making. In this study, we demonstrate its suitability to mediate the incorporation of e-flows into diversion management planning, fostering the realization of an adaptive management approach. We used the case study of the Pas River, Northern Spain, as the setting for the optimization of surface water diversion. We considered e-flow requirements for three key river biological groups to reflect conditions that promote ecological conservation. By drawing from hydrological scenarios (i.e., dry, normal, and wet), our assessment showed that the overall target water demand can be met, whereas the daily volume of water available for diversion was not constant throughout the year. These results suggest that current the decision making needs to consider the seasonal time frame as the reference temporal scale for objectives adjustment and monitoring. The approach can be transferred to other study areas and can inform decision makers that aim to engage with all the stages of the adaptive water management cycle. [ABSTRACT FROM AUTHOR]
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- 2021
- Full Text
- View/download PDF
26. Conservation of Dragonflies : Sentinels for Freshwater Conservation
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Michael J Samways and Michael J Samways
- Subjects
- Dragonflies--Conservation, Freshwater biodiversity conservation, Freshwater habitat conservation
- Abstract
Dragonflies are among the most familiar and popular of all insects, deeply embedded in human cultural history. They are iconic and tell us much about the environments in which we and they live. Their conservation is an important part of biodiversity conservation. One modern dragonfly species is listed as extinct, with many others currently threatened. It is now essential to increase conservation efforts towards saving these threatened species, with strategies now available for doing this. Recovery of dragonfly populations goes hand in hand with improvements to both freshwater conditions and bank vegetation quality. In contrast, some other dragonfly species have benefitted greatly from human transformation of the landscape, with artificial ponds in particular, increasing the population levels of many species. In turn, climate change is seeing many geographical range shifts. Dragonflies are variously sensitive to the health of freshwater systems, and the quality of vegetation along rivers and around ponds. Dragonflies are excellent indicators in these times of great concern over the quality of our freshwater supplies. Their wide range of sensitivities enables us to measure the extent to which freshwater ecosystems are either deteriorating or are improving when we undertake restoration. They enable us to gauge how well we are conserving freshwaters, whether ponds and lakes, streams or rivers. They are also good umbrellas for many other freshwater inhabitants, which altogether reflect the health of a freshwater system. Conservation of Dragonflies: Sentinels for Freshwater Conservation is for naturalists, citizen scientists, entomologists and conservation scientists, as well as practitioners and policy makers around the world.
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- 2024
27. Applied Freshwater Biology
- Author
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John S. Richardson and John S. Richardson
- Subjects
- Freshwater biology--Textbooks
- Abstract
Through rivers, wetlands, streams, and lakes, the flow of water sustains life. In addition to the myriad lifeforms that freshwater ecosystems support, including our own, they also provide opportunities for recreation and personal reflection. Unfortunately, our freshwaters have become seriously impacted and degraded by various stressors, including pollution, forestry, agriculture, urbanization, exploitation of species, and more. In this comprehensive book, Richardson lays out the origins and nature of the most prominent environmental stressors to freshwater systems. The first two chapters provide a review of freshwater biology and hydrology. Each of the next 12 chapters focuses on a particular class of stressors, interactions they may have with other stressors, and a range of solutions currently available to mitigate the problems they cause. The last two chapters pull together key concepts to focus on the restoration of freshwater ecosystems and the importance of long-term monitoring. This work is ideally suited for students in upper and graduate-level college courses focused on freshwater ecology, biology, environmental sciences, and environmental engineering, as well as practitioners in these respective fields. Today, more than ever, we need trained individuals who understand how to protect and restore freshwater ecosystems for both human and non-human use, and this book provides the essential information required to get there. Key Features:Provides 28 case studies demonstrating scientific applications for the mitigation of stressors/impacts on aquatic ecosystems and nearly 100 color illustrations and charts Delves into impacts from both point source and non-point source pollution Addresses issues with water withdrawals and transfers, as well as flow management and channelization Discusses solutions to problems resulting from erosion and sediment transport Designed for use as a one-term college course, with each chapter covering two class periods Chapters include thought-provoking homework activities for students Includes comprehensive references for additional reading and research WAV features selected graphs, tables, and images from the book—available from the Web Added Value Download Resource Center at jrosspub.com/wav
- Published
- 2024
28. The Biology and Ecology of Streams and Rivers
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Alan Hildrew, Paul Giller, Alan Hildrew, and Paul Giller
- Subjects
- Freshwater ecology, Stream ecology, Freshwater biology
- Abstract
The challenges that the world's running water systems now face have never been more numerous or acute; at the same time, these complex habitats remain absolutely crucial to human wellbeing and future survival. If rivers can ever be anything like sustainable, ecology needs to take its place as an equal among the physical sciences such as hydrology and geomorphology. A real understanding of the natural history and ecology of running waters must now be brought even more prominently into river management. The primary purpose of this textbook is to provide the up-to-date overview that students and practitioners will require to achieve this aim. The book's unifying focus is on rivers and streams as ecosystems in which the particular identity of organisms is not the main emphasis but rather the processes in which they are involved - specifically energy flow and the cycling of materials. It builds on the physicochemical foundations of the habitat templet and explores the diversity and adaptations of the biota, progressing from the population and community ecology of organisms and linking them to ecosystem processes and services in the wider biosphere via the complexities of species interactions and food webs. These include water quality and patterns of river discharge, as well as aesthetics, waste disposal, and environmental health. While the book is not primarily focused on application per se, each chapter addresses how humans affect rivers and, in turn, are affected by them. A final, future-oriented chapter identifies key strategic areas and sets a roadmap for integrating knowledge of natural history and ecology into policy and management. The Biology and Ecology of Streams and Rivers is an accessible text suitable for both senior undergraduate and graduate students taking courses in both lotic and general ecology as well as more established researchers, practitioners, managers, and conservationists requiring a concise and contemporary overview of running waters.
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- 2023
29. Rivers of Europe
- Author
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Klement Tockner, Christiane Zarfl, Christopher T. Robinson, Klement Tockner, Christiane Zarfl, and Christopher T. Robinson
- Subjects
- Stream ecology--Europe, Rivers--Europe, Water quality management--Europe, Integrated water development--Europe
- Abstract
Rivers of Europe, Second Edition, presents the latest update on the only primary source of complete and comparative baseline data on the biological and hydrological characteristics of more than 180 of the highest profile rivers in Europe. With even more full-color photographs and maps, the book includes conservation information on current patterns of river use and the extent to which human society has exploited and impacted them. Each chapter includes up to 10 featured rivers, with detailed information on their physiography, hydrology, ecology/biodiversity and human impacts. Rivers selected for specific coverage include the largest, the most natural, and those most affected by humans. This book provides the most comprehensive information ecologists and conservation managers need to better assess their management and meet the EU legislative good governance targets. - Includes comparison photos of rivers, along with information on the history and management of each river - Presents summary information on hydrological, ecological and freshwater biodiversity patterns and trends of each river - Highlights environmental issues of great importance to citizens and governments, including fragmentation by dams, pollution, introduction of nonnative species and reductions in biodiversity
- Published
- 2022
30. Nature-based Solutions im Wasserbau – Die Bedeutung natürlicher Prozesse zur Erzielung ökologischer und sozioökonomischer Ziele
- Author
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Flödl, Peter and Hauer, Christoph
- Published
- 2023
- Full Text
- View/download PDF
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