Current and Future Ecological Status Assessment: A New Holistic Approach for Watershed Management

The Paiva River catchment, located in Portugal, integrates the Natura 2000 network of European Union nature protection areas. Resorting to topography, climate and land-use data, a semi-distributed hydrological model (Hydrological Simulation Program–FORTRAN) was run in order to simulate the hydrological cycle of the river and its tributaries. The model was calibrated over a 25-year period and validated within a 31-year period. Its performance was verified by comparing the recorded and simulated daily flows. The values of the Nash–Sutcliffe coefficient of efficiency of 0.95 and 0.76, and coefficient of determination of 0.95 and 0.82, were achieved for calibration and validation, respectively, thus showing a quite satisfactory model performance. Subsequently, the climate change impacts on temperature and precipitation, as well as their extremes, and on the flowrates were also assessed for a future period (2041–2070) under two anthropogenic forcing scenarios (representative concentration pathways 4.5 and 8.5). A procedure for selecting the most relevant metrics for assessing the ecological condition of the Paiva River was developed based upon a set of 52 invertebrate families sampled. Correspondence analyses were carried out for biological datasets (traits/metrics) with physicochemical and land use/land cover matrices separately. Out of all variables, water quality and flow and agriculture land use explained most of the variance observed. The integrated analysis undertaken in the present study is an important advance when compared to previous studies and it provides key information to stakeholders and decision-makers, particularly when planning suitable adaptation measures to cope with changing climates in the forthcoming decades.

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Flood Simulation of Urbanizing Watershed by Coupling Land Use/Cover Changes with Distributed Hydrological Model: A Case Study of Buji River in Southern China

Watershed Management 2020 ◽

10.1061/9780784483060.023 ◽

2020 ◽

Author(s):

Yangbo Chen ◽

Zexing Liu

Keyword(s):

Land Use ◽

Hydrological Model ◽

Southern China ◽

Distributed Hydrological Model ◽

Flood Simulation ◽

Urbanizing Watershed

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Land-use and agriculture in Denmark around year 1900 and the quest for EU Water Framework Directive reference conditions in coastal waters

AMBIO ◽

10.1007/s13280-021-01536-8 ◽

2021 ◽

Author(s):

Bent T. Christensen ◽

Birger F. Pedersen ◽

Jørgen E. Olesen ◽

Jørgen Eriksen

Keyword(s):

Land Use ◽

Water Framework Directive ◽

Coastal Waters ◽

Root Zone ◽

Reference Conditions ◽

Ecological Status ◽

Agricultural Activity ◽

Eu Water Framework Directive ◽

Alternative Approach ◽

The Eu

AbstractThe EU Water Framework Directive (WFD) aims to protect the ecological status of coastal waters. To establish acceptable boundaries between good and moderate ecological status, the WFD calls for reference conditions practically undisturbed by human impact. For Denmark, the nitrogen (N) concentrations present around year 1900 have been suggested to represent reference conditions. As the N load of coastal waters relates closely to runoff from land, any reduction in load links to agricultural activity. We challenge the current use of historical N balances to establish WFD reference conditions and initiate an alternative approach based on parish-level land-use statistics collected 1896/1900 and N concentrations in root zone percolates from experiments with year 1900-relevant management. This approach may be more widely applicable for landscapes with detailed historic information on agricultural activity. Using this approach, we find an average N concentration in root zone percolates that is close to that of current agriculture. Thus, considering Danish coastal waters to be practically unaffected by human activity around year 1900 remains futile as 75% of the land area was subject to agricultural activity with a substantial potential for N loss to the environment. It appears unlikely that the ecological state of coastal waters around year 1900 may serve as WFD reference condition.

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Mixtures of chemicals are important drivers of impacts on ecological status in European surface waters

Environmental Sciences Europe ◽

10.1186/s12302-019-0247-4 ◽

2019 ◽

Vol 31 (1) ◽

Cited By ~ 10

Author(s):

Leo Posthuma ◽

Werner Brack ◽

Jos van Gils ◽

Andreas Focks ◽

Christin Müller ◽

...

Keyword(s):

Water Quality ◽

Quality Management ◽

Surface Waters ◽

Water Quality Management ◽

Ecological Status ◽

Ecological Impacts ◽

Chemical Pollution ◽

Individual Species ◽

Integrated Analysis ◽

Chemical Mixtures

Abstract The ecological status of European surface waters may be affected by multiple stressors including exposure to chemical mixtures. Currently, two different approaches are used separately to inform water quality management: the diagnosis of the deterioration of aquatic ecosystems caused by nutrient loads and habitat quality, and assessment of chemical pollution based on a small set of chemicals. As integrated assessments would improve the basis for sound water quality management, it is recommended to apply a holistic approach to integrated water quality status assessment and management. This allows for estimating the relative contributions of exposure to mixtures of the chemicals present and of other stressors to impaired ecological status of European water bodies. Improved component- and effect-based methods for chemicals are available to support this. By applying those methods, it was shown that a holistic diagnostic approach is feasible, and that chemical pollution acts as a limiting factor for the ecological status of European surface waters. In a case study on Dutch surface waters, the impact on ecological status could be traced back to chemical pollution affecting individual species. The results are also useful as calibration of the outcomes of component-based mixture assessment (risk quotients or mixture toxic pressures) on ecological impacts. These novel findings provide a basis for a causal and integrated analysis of water quality and improved methods for the identification of the most important stressor groups, including chemical mixtures, to support integrated knowledge-guided management decisions on water quality.

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Hydro-Meteorological Trends in an Austrian Low-Mountain Catchment

Climate ◽

10.3390/cli9080122 ◽

2021 ◽

Vol 9 (8) ◽

pp. 122

Author(s):

Gerald Krebs ◽

David Camhy ◽

Dirk Muschalla

Keyword(s):

Hydrological Cycle ◽

Potential Evapotranspiration ◽

Remote Sensing Data ◽

Kendall Test ◽

Adaptation Measures ◽

Mitigation And Adaptation ◽

Regional Impacts ◽

Long Term Trends ◽

Annual Scale

While ongoing climate change is well documented, the impacts exhibit a substantial variability, both in direction and magnitude, visible even at regional and local scales. However, the knowledge of regional impacts is crucial for the design of mitigation and adaptation measures, particularly when changes in the hydrological cycle are concerned. In this paper, we present hydro-meteorological trends based on observations from a hydrological research basin in Eastern Austria between 1979 and 2019. The analyzed variables include air temperature, precipitation, and catchment runoff. Additionally, the number of wet days, trends for catchment evapotranspiration, and computed potential evapotranspiration were derived. Long-term trends were computed using a non-parametric Mann–Kendall test. The analysis shows that while mean annual temperatures were decreasing and annual temperature minima remained constant, annual maxima were rising. Long-term trends indicate a shift of precipitation to the summer, with minor variations observed for the remaining seasons and at an annual scale. Observed precipitation intensities mainly increased in spring and summer between 1979 and 2019. Catchment actual evapotranspiration, computed based on catchment precipitation and outflow, showed no significant trend for the observed time period, while potential evapotranspiration rates based on remote sensing data increased between 1981 and 2019.

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Integrative hydrogeo-ecological assessment of the quantitative and qualitative response of groundwater to hydrological extremes

10.5194/egusphere-egu21-13111 ◽

2021 ◽

Author(s):

Steffen Birk ◽

Johannes Haas ◽

Alice Retter ◽

Raoul Collenteur ◽

Heike Brielmann ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Ecological Status ◽

Urban Land Use ◽

In Situ Monitoring ◽

Drought Indices ◽

Groundwater Levels ◽

Hydrological Conditions ◽

Hydrological Extremes ◽

Observation Wells

An integrative interdisciplinary approach is currently developed to investigate groundwater systems in alpine and prealpine environments and how they respond to hydrological extremes such as droughts, heavy rain and floods in terms of water quantity, hydrochemical quality, and ecological status. The new approach is aimed at improving the understanding of the interaction between physical, chemical, and biological processes in groundwater responses to extreme events as well as developing indicators suitable for an integrative monitoring and management of the aquifers. For this purpose, observation wells of the existing state hydrographic monitoring net have been selected within the Austrian part of the Mur river basin, stretching from the alpine origin to the national border in the foreland. The investigation area thus comprises diverse hydrogeological settings and land-use types. The selected observation wells have long-term records of groundwater levels and are used for sampling campaigns under different hydrological conditions. Groundwater level fluctuations are evaluated using drought indices and statistical approaches, such as auto-correlation and cross-correlation with precipitation and stream stages. Our hydrochemical analyses of groundwater and surface waters also consider compounds indicative of agricultural sources (e.g., nitrate), wastewater-borne micro-pollutants, and stable isotopes of water. These indicators are used to identify different drivers controlling water origin and quality. The ecological status is characterized using microbiological measures, such as total number of bacteria and microbial activity, groundwater fauna, and the qualitative composition of dissolved organic matter (DOM). First results demonstrate a deterioration of water quality from groundwater to surface water and from the alpine region towards the foreland, corresponding to the more intense agricultural and urban land use in the foreland. Linkages between water quality and hydrological conditions are currently being evaluated and will be further examined using UV-Vis spectrometry for high-resolution in-situ monitoring of water quality changes (DOM and nitrate) at selected observation wells.

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Climate and land use change impacts on water resources in Sardinia (Italy)

10.5194/egusphere-egu21-10894 ◽

2021 ◽

Author(s):

Dario Ruggiu ◽

Salvatore Urru ◽

Roberto Deidda ◽

Francesco Viola

Keyword(s):

Land Use ◽

Water Resources ◽

Land Use Change ◽

Hydrological Cycle ◽

Potential Evapotranspiration ◽

Regional Scale ◽

Annual Runoff ◽

Annual Rainfall ◽

Land Use Scenarios ◽

Near Future

The assessment of climate change and land use modifications effects on hydrological cycle is challenging. We propose an approach based on Budyko theory to investigate the relative importance of natural and anthropogenic drivers on water resources availability. As an example of application, the proposed approach is implemented in the island of Sardinia (Italy), which is affected by important processes of both climate and land use modifications. In details, the proposed methodology assumes the Fu&#8217;s equation to describe the mechanisms of water partitioning at regional scale and uses the probability distributions of annual runoff (Q) in a closed form. The latter is parametrized by considering simple long-term climatic info (namely first orders statistics of annual rainfall and potential evapotranspiration) and land use properties of basins.In order to investigate the possible near future water availability of Sardinia, several climate and land use scenarios have been considered, referring to 2006-2050 and 2051-2100 periods. Climate scenarios have been generated considering fourteen bias corrected outputs of climatic models from EUROCORDEX&#8217;s project (RCP 8.5), while three land use scenarios have been created following the last century tendencies.Results show that the distribution of annual runoff in Sardinia could be significantly affected by both climate and land use change. The near future distribution of Q generally displayed a decrease in mean and variance compared to the baseline. &#160;&#160;The reduction of&#160; Q is more critical moving from 2006-2050 to 2051-2100 period, according with climatic trends, namely due to the reduction of annual rainfall and the increase of potential evapotranspiration. The effect of LU change on Q distribution is weaker than the climatic one, but not negligible.

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STUDIES OF THE EFFECTS OF CHANGES IN LAND USE ON THE HYDROLOGICAL CYCLE IN EAST AFRICA BY MEANS OF EXPERIMENTAL CATCHMENT AREAS

International Association of Scientific Hydrology Bulletin ◽

10.1080/02626666509493424 ◽

1965 ◽

Vol 10 (4) ◽

pp. 63-75 ◽

Cited By ~ 16

Author(s):

M. DAGG ◽

J. R. BLACKIE

Keyword(s):

Land Use ◽

East Africa ◽

Hydrological Cycle ◽

Catchment Areas

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Spatially differentiated management-revised discharge scenarios for an integrated analysis of multi-realisation climate and land use scenarios for the Elbe River basin

Regional Environmental Change ◽

10.1007/s10113-012-0279-4 ◽

2012 ◽

Vol 12 (3) ◽

pp. 633-648 ◽

Cited By ~ 20

Author(s):

Tobias Conradt ◽

Hagen Koch ◽

Fred F. Hattermann ◽

Frank Wechsung

Keyword(s):

Land Use ◽

River Basin ◽

Integrated Analysis ◽

Elbe River ◽

Land Use Scenarios ◽

Elbe River Basin ◽

The Elbe River ◽

Spatially Differentiated

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The basin-landscape approach to the protection and condition optimization of the lakes of the national parks

Geology Geography Ecology ◽

10.26565/2410-7360-2020-53-18 ◽

2020 ◽

Keyword(s):

National Parks ◽

Practical Importance ◽

Ecological Status ◽

Nature Management ◽

Lake Basin ◽

Landscape Approach ◽

Nature Protection ◽

Landscape Characteristics ◽

Condition Optimization ◽

Basin System

The essence of the basin-landscape approach to the protection of the lakes of the national parks as an actual direction of research, which is formed at the junction of nature protection landscaping, hydrology and geoecology has been substantiated. The research algorithm, peculiarities of analysis and assessment of the status of the lake-basin system (LBS) have been found out, the factors that worsen the geo-ecological state in the lake and basin subsystems have been revealed, optimization measures in the objects of the nature reserve fund located within the natural reserve have been substantiated. The purpose of the study is to determine the parameters of the structure of lake-basin landscapes (on the example of Zasvitske lake, Nobel National Natural Park, Ukraine), liminary and landscape-metric indicators of the geo-ecological status of the LBS and the factors influencing it as an information and analytical basis for ensuring the protection and management of the LBS located in nature conservation area. The materials of the study were the long-term field landscape-limnological and geo-ecological studies of the authors within the Polesia region of Ukraine and, in particular, the LBS of the Nobel National Nature Park. The research methodology was based on complex physical-geographical methods, hydrological profiling and creation of bathymetric models of reservoirs, hydrochemical diagnostics of water masses of the lakes, geochemical analyses of bottom sediments, landscape mapping using GIS-technologies. The results of geo-ecological (landscape-ecological) researches of the lake-basin system of Zasvitske lake have been presented, in particular, original profiles and bathymetric model of the reservoir, landscape maps of the aqual complex and the lake catchment, limno- and landscape characteristics of the LBS have been shown. Considering the level of anthropogenic transformations of the LBS and the presence of a high proportion of ecologically-stabilizing lands (forests, reservoirs of natural origin), the level of sustainability of the LBS is estimated as high. An assessment of the hydrological characteristics of the reservoir and hydrochemical characteristics allows to attribute this lake to an oligotrophic type. The results of a comprehensive analysis of the geo-ecological parameters of the state of Zasvitske lake and its landscape-limnological functioning indicate the expediency of recreational specialization of nature management in the Nobel National Park, that includes this lake. Scientific novelty. The application of proposed landscape-basin approach and the algorithm of the LBS study increase the possibilities of functional zoning of national parks with high index of lakes, as well as solving the problems of nature protection and optimization of nature management. Practical importance. The created electronic landscape maps and the base of limnometric parameters can be used as reference documents for the certification and cadastral evaluation of the transboundary protected areas of Ramsar type, geo-ecological monitoring and an integrated management of lakes by the basin approach in conditions of intense climate change.

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