Maximum Ecological Potential Research Articles

Abiotic–Biotic Interrelations in the Context of Stabilized Ecological Potential of Post-Mining Waters

The creation of man-made reservoirs has become more common globally and provides many important technical, biological, and socio-economic functions. The study focused on abiotic–biotic and trophic interrelations responsible for ecological potential and biodiversity in potentially stabilized conditions of the aquatic ecosystem. Therefore, the analyses concerned 2014–2015 and 2018–2019, assuming repeatable hydrochemical conditions, in three chambers (C1–C3) of the Kamień sedimentation pond supplied through opencast mine drainage. The studies indicated eutrophic levels and at least good ecological potential. Phytoplankton were quite abundant at an average biomass of 10.0 mg L−1, while zooplankton and planktivorous fish were estimated at 0.51 mg L−1 and 74.3 g m−2, respectively The general order of the growth level in chambers was C-1 > C-2 > C-3, C-1 < C-2 < C-3, and C-1 < C-3 < C-2 for phytoplankton, zooplankton, and planktivorous fish, respectively, and indicated clear differences. Both mechanisms of the top-down and bottom-up effects were revealed in all chambers. Some significant differences between abiotic and biotic (i.e., fish density and biomass, phytoplankton density) factors were recorded on a temporal scale, whereas the density and biomass of planktivorous fish were significantly differentiated on a spatial scale. The stabilized conditions concerned relatively high biodiversity but quite abundant phytoplankton and lower zooplankton abundances, trophic efficiency, and eutrophy under the maximum ecological potential.

Defining Maximum Ecological Potential for heavily modified lowland streams of Northern Italy

In relation to hydromorphological alteration the Water Framework Directive (WFD), a major piece of European legislation, has introduced the concept of Heavily Modified Water Bodies (HMWB). In water bodies falling in this category, hydromorphological modifications are permanent, significantly alter the character of the river and cannot be removed without compromising the use of the water body. In HMWBs a dedicated approach to the evaluation of their status is set, and their Ecological Potential must be assessed. Crucial to the process is the definition of Maximum Ecological Potential (MEP) as the reference conditions for HMWB. In the present paper we aim to define MEP conditions for Italian heavily modified lowland rivers, affected by strong bank protection (i.e. levees or bank reinforcement) in reason of flood protection and land drainage uses. The approach applied to identify MEP conditions follows the one considered for natural (not heavily modified) rivers in Italy and large part of Europe and bases on the identification of ‘reference sites’ representative for the river category and alteration. For the selection of MEP sites environmental features representing mitigation measures and/or expected natural features were considered. The ability of such features in discriminating MEP and disturbed sites was verified by multivariate analyses run on abiotic features (Principal Component Analysis) and biological communities (non-metric multidimensional scaling). We demonstrated differences both in terms of invertebrate community and biological metrics used to assess ecological status (and potential) between MEP and impaired river stretches. Finally, we recognized relevant habitat features able to clearly separate MEP reaches from nonMEP reaches with indication on the type and quantity of measures significant for benthic invertebrates and applicable in lowland Heavily Modified Water Bodies.

A BIOLOGICAL WATER QUALITY ASSESSMENT BASED ON PHYTOBENTHOS AND MACROINVERTEBRATES AT THREE STATIONS ON THE RIVER NERETVA

UDK: 556.115:574.587(282.249 Neretva)
 This paper presents the research results of benthos community (phytobenthos and macroinvertebrates) on three locations of the Neretva River: Glavatičevo, Žitomislići and Višići. According to typology of rivers, the site Glavatičevo belongs undertype 10a, while sites Žitomislići and Višići are undertype JIVT (heavily modified water bodies). Research of the benthos community has been done in December 2016 with the simultaneous monitoring chemical parameters of water. All research states showed a great number and a high diversity of benthic taxa, although sampling was spent in December. The saprobic values of benthos community at the site Glavatičevo indicates to oligosaprobic level, the water unloaded with organic substances. The site Žitomislići points to oligo/betamesosaprobic level, the water a bit loaded with organic substances. The site Višići according to phytobenthos demonstrates to oligo/betamesosaprobic level, while according to benthic macroinvertebrates point to betamesosaprobic level (the water loaded with organic substances). Based on saprobic values and chemical parameters of water in keeping with The decision on the characterization of the surface and underground water, reference conditions and parameters for the detection of water state and water monitoring (Official newspapers FBiH, No. 1/14), a maximum ecological potential has been registered on sites Žitomislići and Višići, while a high ecological status has been registered on the site Glavatičevo.

Predicting the impact of seasonal fluctuations on the potential ecotoxicological risk of multiple contaminants in the River Scheldt discharge into the Western Scheldt estuary

The study site, Land van Saeftinghe, is an area within the Western Scheldt estuary with Special Protection Area (SPA) status for the EU Birds directive. We used a combination of hydrodynamic and water quality monitoring, hydrodynamic and water quality and modeling, ecotoxicity modeling and observations on the ecological status to correlate the water quality to the observed ecological status of the study site.The monitoring and modeling results show that the copper concentrations are elevated above the Maximum Tolerable Concentration (MTR) during the whole year, while zinc and cadmium show a spring peak (>MTR). Other metals, and all the measured organic contaminants where below the MTR.The peak in the three metals during springtime translates into an increase in the ecotoxicity, as expressed by the calculated multi-substance Potentially Affected Fraction (ms-PAF). The ms-PAF peaked at 25% for all organisms, and 30% for benthic invertebrates. The observed ecological status for the study site at the time of monitoring (2000) was Maximum Ecological Potential (MEP). This result seems to be in contradiction with the exceedance of the MTR for three metals during spring time. However the calculated ms-PAF during the spring peak of 25% is deemed acceptable based on current policy, therefore potential ecotoxic stress is within acceptable boundaries. The ms-PAF results therefore do not contradict the MEP status.The evaluation of the ecological status versus the water quality within the EU Water Framework Directive (WFD) can be improved by using the calculated ecotoxicity (ms-PAF) instead of the water quality. We propose an additional step for water bodies which are currently ‘at risk’, based on their chemical status. In this additional step, the ms-PAF is calculated for all contaminants in the water phase, not discriminating between priority and non-priority substances. The outcome of this calculation defines if the water body is at risk.

Gastropods and periphytic algae relationships in the vicinity of a small hydroelectric plant on the Pas³êka River in northeast Poland

Abstract This study of periphytic algae and gastropods differentiation on macrophytes, stones, and dam substrates and the relationships between these communities in the vegetative season of 2001-2003 was conducted in the vicinity of a hydroelectric plant on the Pasłeka River. Damming the river caused decreased water discharge upstream from the plant, and increased it downstream. Thus, oxygen conditions downstream from the plant improved, but high nutrient concentrations were also recorded. Generally, increased orthophosphate concentrations do not allow river waters to be classified as having good or maximum ecological potential. Damming contributed to changes in the growth conditions of the periphytic algae and gastropods and their differentiation. The highest biomass of periphytic algae was noted on the dam, while the highest gastropods biomass was noted on macrophytes. The periphytic algae was dominated by the diatoms Diatoma vulgaris and Melosira varians (epiphyton, dam) and the chlorophytes Ulothrix tenuissima and Spirogyra sp. (epilithon), while the gastropods were dominated by Lymnea stagnalis (macrophytes), Theodoxus fluviatilis (stones), and Radix balthica (dam). The relationship between the gastropods and the periphytic algae on macrophytes and the dam in spring and summer revealed an increase in gastropods biomass and a decrease in periphytic algae biomass. This was indicated by the negative correlation between the biomass of these communities.

Diatoms of the lower Vistula River phytoseston

Abstract This paper presents the results of research on the phytoseston of the Vistula River along a distance of 163 km. The research was conducted between 1994 and 2010. A total of 218 diatom taxa were identified in the phytoseston. A large number of diatoms were represented by only a few specimens, and, in some cases, only in one of the 312 samples examined. Only nine species had the highest constancy of occurrence in the lower Vistula River; however, mostly periphyton and benthos species predominated the phytoseston in the Vistula River at all of the stations. Most of the species were cosmopolitan. The eutrophic conditions of the Vistula River were confirmed by the great number of eutraphentic diatom taxa. The 86 diatom species identified that have high or very high oxygen requirements confirm that oxygen conditions in the river are good. The ecological potential of the Vistula River was rated based on concentrations of chlorophyll a. The worst state, which was moderate, was recorded in 1998 at positions above the dam in Włocławek. Research on the river segment in Torun in the 2007-2010 period indicated the ecological potential had improved from good to maximum. Despite high anthropogenic pressure and major engineering projects, the Vistula River is characterized by good and maximum ecological potential and great biodiversity.

A pragmatic approach to define the ecological potential of water bodies heavily modified by the presence of ports

Abstract Due to the great number of ports along the European coast, defining the ecological potential of heavily modified water bodies (HMWBs) by the presence of ports is crucial in the development of river management plans. Numerous approaches have dealt with the assessment of the ecological status of natural water bodies, but there are few which specifically cover HMWBs. This contribution proposes pragmatic approaches to define the ecological potential of port areas. Besides being coherent with the hydromorphological alterations, the methodologies developed ensure the functioning of the ecosystem while recognizing that the communities and conditions found in HMWBs are highly determined by the major hazards associated to port activities. The main output is a versatile site-specific approach able to identify the best possible indicators and reference conditions (maximum ecological potential; MEP) to evaluate the ecological potential in port areas. The implementation at the port of Santander stressed the importance of considering water, sediments and biological indicators to evaluate the ecological potential, confirming sediments as the main testimony of the contaminant episodes.

Setting the maximum ecological potential of benthic communities, to assess ecological status, in heavily morphologically-modified estuarine water bodies

Investigations on setting benthic macroinvertebrates reference conditions in natural waters have increased recently. Under the European Water Framework Directive, importance is given to research in morphological heavily-modified water bodies (HMWBs), which are very common in countries with high human pressure. However, research has not been undertaken on setting the maximum ecological potential (MEP), as a reference in HMWB. The objective of the present investigation is to set the MEP of two metrics (diversity and richness), used in assessing the ecological status in different benthic indices. The Oiartzun estuary (Basque Country) is used as a case study, which changed morphologically in the 19th Century, following harbour construction. Data obtained from 1874 and the present were used to model changes in currents, water residence time, salinity, volume, and intertidal area. Benthic macroinvertebrate data, from 1995 to 2011, were used to predict 19th Century and present MEP. Changes in the estuary were described: loss of all of the intertidal areas; doubling of the volume; residence time, changing from 2 to 95days; current velocity reduced by 50%; salinity increase. All these factors have led to changes in the benthic communities and the structural variables. Predicted richness and diversity, for 1874, were lower (48–76%) than those at present. Taking into account the differences between natural and modified waters, it is proposed to utilize 75% of the natural reference conditions, as the MEP values for Basque HMWB.

Maximum ecological potential of tropical reservoirs and benthic invertebrate communities

The Reference Condition Approach (RCA) is now widely adopted as a basis for the evaluation of the ecological quality of water bodies. In accordance with the RCA, the integrity of communities found in a given location should be analyzed according to their deviation from the communities that would be expected in the absence of anthropogenic disturbances. The RCA was used here with the aim of defining the Maximum Ecological Potential (MEP) of tropical reservoirs located in the hydrographical basin of the Paraopeba River in the state of Minas Gerais, Brazil. Among the reservoirs, Serra Azul is used as a water supply and is located in a core area of environmental protection where tourism is not allowed and the native vegetation is conserved. The benthic macroinvertebrate communities at 90 sites located in three reservoirs were analyzed and sampled every 3months over 2years. The temporal patterns of the communities in the three reservoirs were analyzed (2nd-STAGE MDS and ANOSIM) and were not significantly related to seasonal fluctuations in temperature and precipitation. Twenty-eight sites belonging to the Serra Azul reservoir were selected to define the MEP of these reservoirs because these sites had the lowest human disturbance levels. The macroinvertebrate taxa present in the selected MEP sites are similar to those of natural lakes and different from the communities of disturbed sites. The biological classification of these sites revealed two groups with distinct macroinvertebrate communities. This distinction was related to climatic variables, bottom substrate type, the presence of gravel/boulders, coarse sand, silt, clay or muck, depth, and the shoreline substrate zone. These two subsets of biological communities and respective environmental conditions can serve as a basis for the future implementation of ecological quality monitoring programs for tropical reservoirs in the study area. This approach can also, however, be implemented in other geographic areas with artificial or heavily modified water bodies.

Development and test of a statistical model for the ecological assessment of tropical reservoirs based on benthic macroinvertebrates

Reservoirs are heavily modified lentic ecosystems. In spite of their differences from natural lakes, it is important to maintain and improve their chemical and ecological status. In the present study, we tested the value of an assessment tool based on the structure of benthic macroinvertebrate communities, to evaluate the Ecological Potential (EP) of tropical reservoirs. We designed a conceptual assessment scheme based on the Reference Condition Approach, and developed a statistical model based on 28 sites classified as having Maximum Ecological Potential, localized in the reservoir of Serra Azul, Minas Gerais, Brazil. Sixty-two disturbed sites from three reservoirs were used to test the model. A classification system based on three EP classes was found to be the best option, and tracked different levels of total dissolved solids, turbidity, total nitrogen and trophic status. This study confirmed the utility of benthic macroinvertebrates as an indicator group of biological quality in reservoirs, and the statistical model applied was effective in providing a measure of the ecosystem health of the reservoirs. As a further improvement, the level of taxonomic resolution for certain groups such as chironomids could be increased, because knowledge of the species composition may provide a better discrimination of intermediate degradation levels.

A method to assess ecosystem services developed from soil attributes with stakeholders and data of four arable farms

Ecosystem-service indicators and related accounting units are crucial for the development of decision frameworks for sustainable land management systems. With a management concept using ecosystem services, land-use expectations can be linked to quantifiable soil features in a defendable and transparent way. A method to define a set of site-specific ecosystem services and indication system for quantification was set-up and run. First, we interviewed a wide group of land users profiting from ecosystem services of the soil at four arable farms in the polder Hoeksche Waard (S-SE of Rotterdam, the Netherlands). Subsequently, site-specific ecosystem services were defined and weighted according to land use expectations at different spatial and temporal scales. Second, a practical set of indicators was taken from 'Best Professional Judgment' and used to quantify the performance of the ecosystem services for these four farms. The indicators were derived from biotic and abiotic soil parameters. The performance of ecosystem services was related to a reference situation (MEP: maximum ecological potential) with the same land use and soil type combination (i.e., arable fields on silt loam) taken from the database of our national soil survey. In many cases, the performance of ecosystem services was relatively poor if compared to MEP. However, the performances of natural attenuation and/or climate-related services were better. In addition, the different management of these farms (i.e. conventional, intensive and organic farming) was reflected in the performance of the ecosystem services of their soils. Third, land management measures to improve the targeted ecosystem services were incorporated in the outlined method, but not worked out with illustrative field data in this study. Together with concordant data, we show opportunities for a quantification of ecosystem services to improve land-users' awareness and to assess management sustainability.

Development of Classification System and Biological Reference Conditions for Bulgarian Rivers and Lakes According to the Water Framework Directive

ABSTRACTThe study focused on sampling procedures and analysis of biological and physico-chemical quality elements (according to the EU Water Framework Directive (WFD)) and aimed at defining reference conditions and sites, maximum ecological potential, specific physico-chemical and hydromorphological conditions for assessed surface water types of “rivers” and “lakes” categories. Biological quality elements (BQE) and their metrics were selected in compliance with WFD requirements and its additional guidelines. All five compulsory BQEs were surveyed (phytoplankton, macrophyte flora, phytobenthos, macrozoobenthos, fish fauna) towards establishing rivers and lakes ecological status and potential. Current research indicates a certain necessity for integration of all assessments and analysis of ecological status/potential and their direct link to the measurement and monitoring programmes in Bulgaria.

Reference condition and maximum ecological potential of macrophyte-rich floodplain lakes along the Lower Rhine

Reference condition and maximum ecological potential of macrophyte-rich floodplain lakes along the Lower Rhine