Suchergebnisse

The Schelde is a lowland river originating in the northern part of France (St. Quentin), and entering the North Sea near Vlissingen, The Netherlands. The estuary covers about half of its length (355 km) as the tidal influence is stopped by sluices near Gent 160 km upstream. We focused on the Zeeschelde, the estuarine part in Flanders comprising a mesohaline, an oligohaline and a freshwater tidal zone. The Zeeschelde is subject to severe eutrophication as it receives high inputs from domestic, industrial and agricultural activities. The ecological values and nature conservation interests of the Zeeschelde are taken into consideration by a series of (inter)national policy instruments, aiming at a sustainable management and conservation of this aquatic environment. As a result several management plans apply also to the Zeeschelde or to parts of it. The most far-reaching plans are the Long Term Vision for the Schelde estuary (LTVS) and the updated Sigmaplan which combine ecological rehabilitation and sustainable habitat creation with flood control measures and navigation requisites. Compliance with almost all national and international agreements requires monitoring of biota. In the WFD fish is one of the biotic quality elements to be used in order to assess the ecological status of transitional waters. Species composition, abundance and the proportion of disturbance-sensitive species should be quantified. Any distortion attributable to anthropogenic impact is calculated by means of the Ecological Quality Ratio (EQR), representing the difference between monitored data and reference conditions. The fish-based assessment tool that we developed was designed to comply with these criteria. In addition it can be used on a metric level to assess fish species of special interest under the Habitats Directive. The fish assemblages in the Zeeschelde were described based on sampling results recorded over a period of 13 years. An overview was provided of the temporal and spatial variation in those assemblages along the salinity gradient in the Zeeschelde estuary (Chapter 2). The species richness and abundance increased over these years in the different salinity zones of the Zeeschelde. Between 1991 and 2008 a total of 71 fish species were recorded within this part of the estuary. Each salinity zone is characterised by a typical fish assemblage, although some species are shared between all three zones. The observed increase since 2007 in species richness in the freshwater and oligohaline zones coincides with a remarkable increase in dissolved oxygen. Guild specific qualitative Maximal and Good Ecological Potential (MEP/GEP) lists were composed for the different zones within the Zeeschelde estuary and its tidal tributaries (Chapter 3). The geographical range and ecological demands of the detected fish species were assessed. The outcome was decisive for acceptance within these lists, which served to develop a fish-based index for the Zeeschelde. In chapter 4 the ecological goals and associated habitat needs were described for fish populations in estuaries. The Zeeschelde was presented as a case study for the description of ecological goals for the fish species listed in the MEP/GEP lists. In order to make the method more widely applicable we first classified fishes into guilds, relevant for the formulation of ecological goals. Next we described guild-specific ecological goals and defined habitat needs linked with a proper functioning of the estuarine ecosystem. The habitat needs ensure the completion of all lifecycle stages: spawning, breeding, feeding and growth to maturity. A hierarchical approach was adopted to define the goals and habitat needs: from a regional scale to habitat level. On a regional and basin wide scale the essential habitat need is connectivity, on an estuarine scale this is space and on a habitat scale diversity is most important. The proposed ecological goals need further quantification. However in general the rehabilitation of marshes and mudflats and the enhancement of flood control areas as fish habitats, with special attention for connectivity with the estuary, will significantly increase the carrying capacity of the Zeeschelde for most of the relevant populations. In Chapters 5 and 6 two essential habitat needs are discussed in detail. In chapter 5, we modelled the environmental constraints controlling the movements of anadromous and catadromous fish populations that migrate through the tidal watershed of the river Schelde. For remaining diadromous populations (flounder, three-spined stickleback, twaite shad, thinlip mullet, European eel and European smelt) a data driven logistic model was parameterized. We modelled the presence/absence of fish species in samples taken between 1995 and 2004 as a function of temperature, dissolved oxygen, river flow and season. We demonstrated that it is possible to make acceptable predictions about the future spatiotemporal distribution of migrant fishes, even if only relatively limited information is available. An important management issue that derived from our study is that it is essential to avoid at all times DO concentrations below 5 mg l-1 in the freshwater and brackish tidal estuary of the watershed. Restoration of habitats such as marshes and mudflat areas will enhance aeration of the water and help to avoid severe DO drops. The use of tidal marshes for fish and the influence of creek characteristics on the visiting fish assemblages were assessed (Chapter 6). As expected the influence of the salinity gradient is reflected in the different fish assemblages. We caught a high proportion of juveniles suggesting that the creeks are a juvenile habitat. The highest fish abundance was recorded in summer (after hatching) because then juveniles seek shelter in the creeks. It was also observed that the visit frequency was related to creek dimensions and inundation time. Larger creeks, lower in the tidal frame and with a more complex structure, as they include side creeks and permanent pools, are of higher interest for fish. We also observed a positive effect of rivulets on the mudflat adjoining the tidal marsh as they guide the fish towards the creeks. These observations are important for the design of tidal wetland restoration projects. In chapters 7 and 8 different approaches to define a fish-based evaluation tool to assess the ecological quality status of an estuary (the Zeeschelde) were described. The fish index comprises metrics which are ecologically relevant variables that are sensitive to human pressures. A first step in the selection of these metrics consisted in assessing how they evolve along a pressure gradient (graphical selection). In chapter 7 a new concept in the index development was introduced i.e. the balance between type I (false positive) and type II (false negative) errors. The magnitude of these errors was expressed as the area under the curve (AUC). Graphical screening assured the selection of metrics responsive to anthropogenic degradation. We scored metrics by judging the metric value variation in the best available site (quintiles). A forward stepwise regression selected the metric with the best balance between the type I and type II error. Metric selection was continued until the lowest AUC was obtained. To define the EBI thresholds we fixed the maximum type I error of each integrity class threshold at 10%. It was a major concern that not all quality classes can be discriminated because of unbalanced pre-classification data. Secondly the final index had a high type II error, although we believe both types of error should be small. Therefore in the next chapter a different approach was used in order to obtain a better index. In chapter 8 we described the development of a Zone specific fish-based multimetric Estuarine index of Biotic Integrity (Z-EBI) based on fish surveys data from the Zeeschelde estuary (Chapter 2). Again we pre-classified sites using indicators of anthropogenic impact and selected metrics showing a monotone response with pressure classes for further analysis. Metric values were calculated using pooled annual data within one salinity zone and expressed as catch per unit effort. Metrics were selected using a Principal Component Analysis (PCA) combined with a redundancy test. We defined thresholds for the Good Ecological Potential (GEP) from salinity zone specific references developed in chapter 3. andapplied a modified trisection for the other thresholds (moderate, poor and bad). The Z-EBI is defined by the average of the metric scores calculated over a one year period within each zone and translated into an Ecological Quality Ratio (EQR) to comply with the European Water Framework Directive (WFD). The indices integrate structural and functional qualities of the estuarine fish communities and can be used to assess the ecological quality of the Zeeschelde. We successfully validated the Z-EBI performances for habitat degradation in the various habitat zones. With this new index we encompass small temporal and spatial variations within the estuary. It accounts for the seasonal variation and covers the complete salinity zone, which is an improvement compared to the previous index. The developed indices are able to make the distinction between impacted and unimpacted (GEP) status. Our results showed that the ecological status of the Zeeschelde at present varies from bad to moderate. A comparison of the average scores obtained with EBI and Z-EBI indicated that in those cases where a different appreciation appeared, the EBI scores lower. This confirms our view that local and temporal appreciations are too sensitive to small variations, which do not necessarily represent an overall negative impact on the ecosystem functioning. Implementing rehabilitation and conservation measures will improve the ecological quality status of the Zeeschelde. At present the Z-EBI corresponds best with the demands from the different legislations and provides the most holistic information from an ecological point of view. ; De Schelde ontspringt in St. Quentin (Frankrijk) en mondt 355 km verder uit in de Noordzee nabij Vlissingen (Nederland). Tussen Gent en de monding is de Schelde over zowat 160 km onderhevig aan getijdewerking. In deze studie concentreerden we ons op de Zeeschelde (Belgisch estuarium) met haar drie saliniteit zones: een mesohaline zone, een oligohaline zone (inclusief de Rupel) en een zoetwater zone (inclusief de Durme, Dijle, Zenne, Grote en Kleine Nete). De Zeeschelde wordt vervuild door huishoudelijk en industrieel afval en ten gevolge van landbouwactiviteiten. Toch heeft de Zeeschelde een hoog ecologisch potentieel en een natuurwaarde die door nationale en internationale richtlijnen worden gewaarborgd. Voor het verzekeren van natuurherstel, gecombineerd met veiligheid en toegankelijkheid, werd gekozen voor het wenselijk alternatief van het geactualiseerd Sigmaplan. Als onderdeel van de studies die nagaan of aan de verschillende richtlijnen wordt voldaan, is in de meeste gevallen ook een beoordeling vereist van de status van biota. In de Kaderrichtlijn Water wordt vis vooropgesteld als een kwaliteitselement voor het beoordelen van de ecologische status van overgangswater. Een verschuiving tengevolge van menselijke activiteiten in de soortensamenstelling, abundantie en aantal gevoelige soorten wordt weergegeven in een ecologische kwaliteitsratio, die het verschil aantoont tussen de actuele en de referentietoestand. Daarom ontwikkelden we een visindex die gevoelig is voor dergelijke verschuivingen en die tevens elementen opneemt die van belang zijn voor de habitatrichtlijn. Op basis van vangstgegevens, verzameld over 13 jaar, beschreven we de vissamenstelling in de Zeeschelde langsheen de zoutgradiënt (Hoofdstuk 2). In totaal vingen we voor de drie saliniteitszones 71 verschillende soorten. Elke zone was gekenmerkt door een typische visgemeenschap, die we verder onderverdeelden in gildes of ecologische groepen. De toename van het aantal soorten in de verschillende zones viel samen met een verbetering van de waterkwaliteit (opgeloste zuurstof). Op basis van de recente en historische visstandgegevens stelden we referentielijsten samen diebeantwoorden aan het Maximaal Ecologisch Potentieel (MEP) en het Goed Ecologisch Potentieel (GEP) van de drie saliniteitzones in de Zeeschelde vis (Hoofdstuk 3). De geografische spreiding en ecologische vereisten van elke vissoort waren bepalend om deze al dan niet in de lijst op te nemen. Deze referentielijsten werden gebruikt voor het ontwikkelen van een zone specifieke visindex voor het Zeeschelde estuarium. We groepeerden de vissen uit de referentielijsten in gildes en expliciteerden hun ecologische doelstellingen en de ermee geassocieerde habitateisen (Hoofdstuk 4). De aanwezigheid van de vereiste habitatten garandeert dat de betrokken vissen hun levenscyclus kunnen voltooien. Op regionale en bekkenschaal houdt dat ondermeer ecologische connectiviteit in, op estuariene schaal is dat voornamelijk ruimte en op habitatniveau diversiteit. De bescherming en de maatregelen natuurherstel waarbij slikken, schorren en gecontroleerde overstromingsvlaktes worden gerealiseerd, verhogen de draagkracht van de Zeeschelde voor vis. De habitateisen beschreven in hoofdstuk 4 zijn kwalitatief. Om de connectiviteit te kwantificeren modelleerden we omgevingsvariabelen die een belangrijke invloed uitoefenen op de migratie van diadrome vispopulaties in de Zeeschelde (Hoofdstuk 5). Zo modelleerden we de aan- en afwezigheid van migratoren in de Schelde in functie van temperatuur, opgeloste zuurstof, stroomsnelheid en seizoen. We toonden aan dat met relatief weinig informatie aanvaardbare voorspellingen konden gemaakt worden van de ruimtelijke en tijdelijke verspreiding van migrerende vissoorten. Dat in het zoetwater- en brakwatergedeelte een zuurstofconcentratie van minstens 5 mg l-1 een noodzakelijke habitatvereiste blijkt te zijn, is belangrijk voor het estuariumbeheer. De realisatie en bescherming van afdoende oppervlakten slikken en schorren zijn noodzakelijk om de zuurstofuitwisseling te verbeteren. Het gebruik van schorren door vissen en het belang van kreekeigenschappen voor de bezoekende visgemeenschappen verduidelijkten we in hoofdstuk 6. Naargelang het zoutgehalte troffen we in de schorkreken andere visgemeenschappen aan. In alle schorkreken vingen we hoofdzakelijk juveniele exemplaren met een piek in de zomer. De positie van de kreek in het getijdevenster beïnvloedt de bezoekfrequentie van de vissen, dit is ook het geval bij aanwezigheid van een geul op het slik vóór het schor. Kreken die relatief lager liggen, breed zijn en vertakkingen hebben met permanente poelen worden het meest bezocht door vissen. In hoofdstuk 7 beschreven we de ontwikkeling van een op vis gebaseerd scoresysteem: de visindex (EBI). Deze visindex bevat metrieken of ecologisch relevante variabelen die gevoelig zijn voor verstoring. Een metriek die een staalnameplaats bijna altijd een zelfde status geeft als deze bepaald op basis van de omgevingsindicatoren is een goede metriek met een kleine foutenmarge. Het evenwicht tussen type I- en type II- fout kan met een curve weergegeven worden en het oppervlak onder deze lijn (AUC: area under the curve) is een maat voor de performantie van de metriek: hoe kleiner de oppervlakte hoe performanter. Met een stapsgewijze regressieanalyse selecteerden we eerst de metriek met de laagste AUC, waarna we de volgende metriek selecteerden die in combinatie met de eerste een nog kleinere AUC geeft tot uiteindelijk de AUC niet verder afnam. Finaal selecteerden we vijf metrieken en de spreiding van hun gemiddelde waarde werd gebruikt om de grenswaarden van de index te bepalen. Deze index is in staat op basis van één afvissing de kwaliteit van een staalnameplaats vast te leggen. Hij vertoont echter nog enkele tekortkomingen en daarom ontwikkelden wemet een alternatieve benadering nog een andere visindex voor de Zeeschelde (Hoofdstuk 8). Bij de alternatieve benadering opteerden we om voor het berekenen van de metriekwaarden alle gegevens per jaar binnen één zone te combineren. Dat impliceerde dat de resulterende index (Z-EBI) de Zeeschelde per saliniteitzone evalueert, gebaseerd op jaargegevens. Metrieken werden geselecteerd met behulp van statistische analyses, gecombineerd met ecologische achtergrondkennis. De referentielijsten werden gebruikt om grenswaarden voorelke geselecteerde metriek te bepalen. Het gemiddelde van de metriek scores berekend voor één jaar gaf de indexwaarde aan. Deze werd vertaald in een ecologische kwaliteitsratio (EQR) in overeenstemming met de Kaderrichtlijn Water. In elke zone beoordeelt de index structurele en functionele kwaliteiten en bepaalt hij de staat van de ecologische kwaliteit van de Zeeschelde. Door het gebruik van jaargegevens hielden we rekening met seizoensverschillen en door het beoordelen van een totale zone werden eveneens ruimtelijke verschillengeïntegreerd. De indexwaarden toonden aan dat de ecologische status van de Zeeschelde naargelang de zone varieert tussen slecht en matig. Bij een vergelijking van de EBI en Z-EBI scores stelden we vast dat bij een verschil de EBI steeds lager scoorde. Dit bevestigde onze hypothese dat het gebruik van locale en tijdelijke beoordelingen te gevoelig is voor kleine veranderingen die daarenboven niet noodzakelijk een negatieve invloed hebben op het functioneren van het ecosysteem. Momenteel beantwoordt de Z-EBI het best aan de criteria van verschillende richtlijnen en vanuit een ecologisch perspectief verschaft ze de meest holistische beoordeling.

AbstractEvaluation of the ecological health of rivers requires a focused examination of how biological indicators respond to chemical stressors to offer key insights for effective conservation strategies. We examined the influence of stressors on aquatic ecosystems by analyzing various ecological entities and biotic integrity metrics of fish communities. A nonmetric multidimensional scaling (NMDS) approach was applied to determine scores based on 19 fish ecological entities (FEs) and a fish-based multi-metric index of biotic integrity (mIBI-F). The composition of fish communities in reference clusters differed from the disturbed clusters due to instream chemical stressors. These chemical stressors, including high levels of nutrients, organic matter, and ionic/suspended solids, were linked to variation in the key indicator FEs, whose guild identities were closely associated with instream chemical degradation. The scores of FEs (abundance weighted) and mIBI-F metrics in the first NMDS axis (NMDS1) were significantly linked with chemical health indicators (p < 0.001), such as total phosphorus (R2 = 0.67 and 0.47), electrical conductivity (R2 = 0.59 and 0.49), and chlorophyll-a (R2 = 0.48 and 0.25). These NMDS1 scores showed better accuracy than the conventional mIBI-F score in capturing river ecological health linked with chemical health status as determined by a multi-metric index of water pollution. Our study suggests that based on the ordination approach, the biological integrity of these systems reflected the chemical health.

Due to their sensitivity and dramatic declines, freshwater mussels are prime targets for conservation and environmental monitoring. For this, however, information is needed on life history and ecological traits, which is lacking in many taxa, including threatened species. Species recently described or recognized as valid are of particular concern, due to the shortage of even basic knowledge. A case in point is the recently recognized and Near Threatened dolphin freshwater mussel Unio delphinus Spengler, 1793, which is endemic to the western Iberian Peninsula and has suffered marked population declines. To overcome information gaps for U. delphinus, we carried out a holistic biological study across the species range, aiming to: i) estimate the area of occupancy (AOO) and extent of occurrence (EOO) based on updated distribution data taken from the literature and recent surveys; ii) estimate growth patterns from biometrical (shell dimensions and growth annuli) measurements taken on specimens from seven populations; iii) estimate sex ratios from gonad tissue biopsies collected on specimens from eight populations; iv) estimate gametogenesis and sex ratio through histological examination of gonad and gill tissues collected monthly for a year, from a single population; and v) determine host species from infestation trials of glochidia with co-occurring fish species. We estimated an EOO of 706 km2 and an AOO of 61 km2, which together with data on declines assigns the species to the Endangered category using IUCN criteria. Unio delphinus was found to grow faster and to be shorter-lived (up to 11 years, maturity at around 2 years old) than other European freshwater mussels. Growth and life span are similar across the range in lotic habitats, but different from that in lentic habitats. The larvae of U. delphinus may attach to most co-occurring fish species, but only native species were effective hosts. Native cyprinids, especially those from the genus Squalius, seem to be the primary hosts. Overall, the information provided contributes to a better conservation status assessment, selection of conservation and rehabilitation areas, guidance for the establishment of propagation programs and better timing for specimens' manipulation including monitoring and possible translocations. The framework presented here highlights the importance of basic biological studies to define good ecological and physiological status. ; This work was supported by Portuguese FCT – Foundation for Science and Technology, Projects FRESHCO: Multiple implications of invasive species on Freshwater Mussel co-extinction processes (PTDC/ AGR-FOR/1627/2014-04/SAICT/2015), MUSSELFLOW: Host-dependent evolution, ecology and conservation of freshwater mussels under varying hydrological conditions: consequences of climate change (PTDC/BIA-EVL/29199/2017), and ConBiomics: The missing approach for the Conservation of freshwater Bivalves Project N° NORTE-01-0145- FEDER-030286, co-financed by COMPETE 2020, Portugal 2020 and the European Union through the ERDF. FCT also supported MLL under grant (SFRH/BD/115728/2016), CM under grant (SFRH/BD/111133/ 2015) and also through Strategic Funding UID/Multi/04423/2019. PB was supported by EDP Biodiversity Chair. ; info:eu-repo/semantics/publishedVersion

It has been analyzed the system of social and ecological monitoring, which allows expanding indicator set of characteristics of the state and dynamics of society to the limits covering not only social processes, but all aspects of relationship between society and nature. The system of social and ecological monitoring allows obtaining the sociological information promoting sustainable development of society. It allows to consider in detail socially ecological processes and the phenomena, quickly to find changes and general tendencies of transformation of such processes and phenomena, to analyze simultaneously all social subjects according to their role in the development of social and ecological processes, to provide use of new methods of environmental and social assessments. Indicator set of characteristics of state and change of society in the course of social and ecological monitoring extends to the limits covering not only social processes, but also all aspects of communications between society and nature. Object of studying of social and ecological monitoring is a society and its life environment. The society loses signs of totality and alignment. It is shown as changeable set of local fragments which are poorly conformed to each other and therefore they comprise variety of scenarios of further development. As perceptible improvement of ecological situation is inseparable from rationalization of economy and growth of social involvement of citizens at the specific level of local community, this level is considered to be optimum for research. At this level features and possibilities of solution of local problems can be considered; its cultural, ethnic and religious features are taken into account, lasting experience of aboriginal population and its tradition is considered, equitable distribution of environmental risk in community is provided. Receiving reliable information about changes in public consciousness, in public orientations, their influence on ecological consciousness of people on extent of their concern in the ecological situation, on ecological activity and factors inducing to this activity is possible only when performing large-scale social and ecological monitoring. Early warning of growth of social tension in regions and in the country in general, formations of the new ecological consciousness corresponding to the modern period of development of world civilization requires studying of public opinion by state bodies, public organizations, parties and political movements, scientists and experts, members of media and education systems. Ecological awareness is a basis of ecological thinking formation. It will allow changing focus of consumer society from thoughtless ruin and exploitation of nature to careful attitude to its resources, understanding of their authentic value. Studying of public opinion on environmental problems by means of mass survey is necessary, but it is insufficient condition of forecasting of people social behavior. When considering public opinion as one of regulators of social behavior in the conditions of social and ecological intensity it is necessary to consider also the possibility of its change under influence, first of all media, rumors, activities of system of ecological education. Value of social and ecological monitoring is that it, except for fixing of changes of public opinion of the population, allows determining efficiency of specific actions for impact on public opinion of such factors as orientation and intensity of massmedia appeals to ecological subject.

Current environmental degradation and resource depletion challenge our societies in their fundaments. Scientific evidence show that the negative impacts of our economies are growing, while wellbeing doesn't seem to follow this trend. Degrowth theories - i.e. a transitional period to reach global sustainability - tries to solve the ecological and social crisis through a shift in our socio-economic paradigm. To support political and societal decision-making processes, some indicators could be helpful. In all societies, the agricultural world can be seen as the most important sector of production. We are not completely reinstituting Physiocrats' view, but agriculture is well presented as the foundation of the activities, due to many implications in others sectors. Our way to be farmer can determine the quality of soils, water and food. Health is strongly related to what we eat. More, here we can find precious indications about our relation with Nature and the way we consider it: fight or collaboration. The global crisis occurring in the farmer world - plenty of farms disappear every year around the world - is not a detail. Optimistically, many considerations are dedicated on tomorrow agriculture: it should be free from petrol use (as inputs and energy), extensive, local and environmentally sound. Farmers have to live directly from what they produce but this sector should be away from global profit focus. We can see it as a public service, providing many implications in other sectors and pushing them into the transitional period. Another application of the precautionary principle is the upholding of GMO on laboratories. This kind of seeds is directly linked with an intensive, centralized and profit-oriented agriculture. In this article, we propose a set of indicators focused on the agricultural world in a degrowth transition period. These indicators could next be aggregated in one index, able to launch the debate and its appropriation by the Civil Society. We propose to construct such an index with a kind of pyramidal approach, highlighting a gradation inside the different levels. The current paper represents the beginning of a work in progress. The indicators are submitted to the debate, in a way to underline his abilities to engage the paradigm shift.

Current environmental degradation and resource depletion challenge our societies in their fundaments. Scientific evidence show that the negative impacts of our economies are growing, while wellbeing doesn't seem to follow this trend. Degrowth theories - i.e. a transitional period to reach global sustainability - tries to solve the ecological and social crisis through a shift in our socio-economic paradigm. To support political and societal decision-making processes, some indicators could be helpful. In all societies, the agricultural world can be seen as the most important sector of production. We are not completely reinstituting Physiocrats' view, but agriculture is well presented as the foundation of the activities, due to many implications in others sectors. Our way to be farmer can determine the quality of soils, water and food. Health is strongly related to what we eat. More, here we can find precious indications about our relation with Nature and the way we consider it: fight or collaboration. The global crisis occurring in the farmer world - plenty of farms disappear every year around the world - is not a detail. Optimistically, many considerations are dedicated on tomorrow agriculture: it should be free from petrol use (as inputs and energy), extensive, local and environmentally sound. Farmers have to live directly from what they produce but this sector should be away from global profit focus. We can see it as a public service, providing many implications in other sectors and pushing them into the transitional period. Another application of the precautionary principle is the upholding of GMO on laboratories. This kind of seeds is directly linked with an intensive, centralized and profit-oriented agriculture. In this article, we propose a set of indicators focused on the agricultural world in a degrowth transition period. These indicators could next be aggregated in one index, able to launch the debate and its appropriation by the Civil Society. We propose to construct such an index with a kind of pyramidal approach, highlighting a gradation inside the different levels. The current paper represents the beginning of a work in progress. The indicators are submitted to the debate, in a way to underline his abilities to engage the paradigm shift.

The call for ecosystem considerations in marine management has instigated the use of ecosystem indicators. Many ecosystem indicators have been suggested under new policy frameworks such as the EU Marine Strategy Framework Directive or the Common Fisheries Policy. But many of these indicators are still under development and cannot be considered as yet operational for environmental assessments. A common reason for this lack of operationability is the absence of valid assessment benchmarks. This study introduces a two-stage approach for the benchmarking and assessment of time series (TSBA) against apriori chosen rationale of improvement or maintenance of current conditions. TSBA uses breakpoint- and trend-analysis to obtain long-term benchmarks and assess short term progress. Depending on the outcome of both analyses the action requirements for management can be determined. The method is exemplified on a case study on the size-structure of large North Sea gadoid stocks, which are considered as being sensitive to the impacts of fishing. Three out of six stocks reached their assessment benchmarks, while the three other stocks failed. TSBA is generic and can be applied to any indicator used within any marine policy assessment framework. A strength–weaknesses–opportunity–threat analysis (SWOT)investigated the advantages and disadvantages of TSBA in the context of the currently high political demand of operational ecosystem indicators. Contrary to benchmarks derived from ecological conceptsor pressure-state relationship TSBA benchmarks are not specifically linked to limits of resilience or sustainability. However, TSBA may be especially useful in situations where assessment benchmarks from other sources will not be readily available or are associated with high uncertainty.

Environmental positive externalities from public provision, such as the benefits yielded from the public measure of nature conservation, are often not internalized. Potential sub-optimal public service provision can be expected from such a condition, leading to inefficiency, if the benefits at a greater territorial scale are not acknowledged. This holds particularly true for intergovernmental fiscal relations in a decentralizing multi-tiered governmental system. Moreover, in developing countries the fiscal capacities to perform measures of ecological public functions are limited with their fiscal needs for these functions often appearing to outweigh their fiscal capacities. Research at the interface of the economic theory of fiscal federalism, the sustainability concept, and policies related to conservation and the environment is relatively new. Furthermore, in the literature on environmental federalism the emphasis tends to be comparatively less on the benefits of positive environmental externalities. The essential contribution of this study is an extension of this research field that is still in its infancy by applying the specific case of Indonesia as the context, on account of this tropical country"s ecological significance as well as its recent developments during the fiscal decentralization process. The overall aim of this study is to assess the possibilities of ecological fiscal transfers as a set of instruments in the public sector to internalize environmental externalities. To this end, the study traces the development as well as the current state of intergovernmental fiscal transfers in Indonesia in terms of ecological purposes. On the basis of this knowledge, the study offers new policy perspectives by proposing a number of policy options for ecological fiscal transfers in the context of the functioning fiscal transfer system and institutions between the national and the subnational (province and local) governments as well as among jurisdictions at the same governmental level. The incorporation of an explicit ecological indicator into general-purpose transfers is the first option. The second option is derived from a revenue-sharing arrangement. In this arrangement, two sub-options are proposed: first, shared revenues from taxes are distributed on the basis of the ecological indicator and, second, shared revenues from natural resources are earmarked for environmental purposes. Finally, the third option suggests an extension of existing specific-purpose transfers for the environment. The potential and limitations of the respective options are addressed. Additionally, a short treatment is given to the discourse on the possible mobilization of fiscal resources in the context of tropical deforestation and global climate change. The research concentrates mainly on the first option, namely the incorporation of an ecological indicator into the structure of general-purpose transfer allocation. In order to substantiate an explicit ecological dimension in the transfer, it extends the present area-based approach by introducing a protected area indicator while maintaining the remaining socio-economic indicators in the fiscal need calculation. The parameter values of area-related indicators are adjusted and subject to the properties of the existing formula. The simulation at the provincial level yields the following results. First, more provinces lose rather than gain from the introduced ecological fiscal transfer when compared to the fiscal transfer that they received in the reference fiscal year. Second, on average the winning provinces obtain a higher level of transfer from the introduction of an ecological indicator in the fiscal need calculation. The extent of the average decreases for the losing provinces, however, it is lower compared to the extent of the average gain by their winning counterparts. In terms of spatial configurations of the general-purpose transfer with an ecological indicator, provinces in Papua would benefit most from the new fiscal regime whereas provinces in Java and Sulawesi, with a few exceptions, would suffer a transfer reduction. Kalimantan and Sumatera show a mixed pattern of winning and losing provinces. The analysis on the equalization effects of the general-purpose transfers makes the following important contributions. It suggests that, first, the transfers are equalizing and, second, the introduction of the protected area indicator into the structure of these transfers plays a significant role in the equalizing effect, particularly in the presence of provinces with a very high fiscal capacity and when the area variable is also controlled. All of these new insights are imperative in the design of fiscal policy which intends to integrate explicit ecological aspects into the instruments of intergovernmental fiscal transfers. Since a formula-based fiscal transfer distribution is intrinsically zero-sum, the aforementioned configuration of winning and losing jurisdictions is conceivable. Among other future perspectives, it is the task of further research to explore ecological fiscal transfer instruments and associated measures that on the one hand seek to induce the losing provinces to join their winning counterparts and, on the other hand, are still subject to the requirements of the rational fiscal transfer mechanism.