59 research outputs found
Möglichkeiten und Grenzen geostatistischer Verfahren in den Fischereiwissenschaften : Analyse räumlicher und zeitlicher Variabilität von Fischpopulationen
Análisis espacial de la concentración de metales en el camarón gris Crangon crangon (Linnaeus, 1758) en el Mar del Norte meridional
Spatial distributions of Cu, Pb, Cd, Ni and Zn concentrations in brown shrimps Crangon crangon (Linnaeus, 1758) collected on a cruise of FRV Walther Herwig III to the southern North Sea in January 2004, were investigated on a scale of 18 x 18 km to evaluate the range of spatial autocorrelations for the different variables under study. Semivariogram models obtained by geostatistical procedures indicated a distinct increase in variability for most variables with sampling distance. Only if samples are taken at distances above the estimated values for the practical range of the semivariogram can stochastic independence of the data be assumed. These are 6.6 km for Cd, 3.0 km for Ni and 5.2 km for Pb. Contour plots revealed a clear coincidence of high values for Cd, Ni and Pb with low shrimp mean body wet weight. Nevertheless, spatial autocorrelations were rather weak, since classical and geostatistical population estimates for the means and the 95% confidence intervals were in good agreement. The low detected concentrations of Pb in C. crangon were in good agreement with reported data for decapod crustaceans from other regions. For Zn reported values were distinctly below our 95% confidence intervals, while for Cu they were slightly above and for Cd distinctly above concentrations in C. crangon from this study. For Ni no comparative values exist. We conclude that with this integrated biomonitoring approach metal concentrations could be assessed more precisely and relations between biotic and abiotic variables could be evaluated.Se analiza la distribución espacial de las concentraciones de Cu, Pb, Cd, Ni y Zn en el camarón gris Crangon crangon (Linnaeus, 1758) en muestras recolectadas durante una campaña a bordo del BO “Walther Herwig II” en el Mar del Norte meridional en Enero de 2004, en un área de 18 x 18 km. Se investiga el alcance de las funciones de autocorrelación espacial de las distintas variables estudiadas. El análisis de los modelos de semivariograma obtenidos mediante técnicas geostadísticas indica un aumento de la variabilidad para la mayoría de las variables con la distancia. Sólo cuando se toman las muestras a distancias superiores al alcance práctico del semivariograma se puede asumir independencia estocástica entre los datos. Los alcances calculados son 6.6 km para Cd, 3.0 km para Ni y 5.2 km para Pb. Los mapas de isodensidad muestran una clara coincidencia de altos valores de Cd, Ni y Pb con valores bajos de peso medio húmedo de camarón. Sin embargo, las autocorrelaciones espaciales observadas son relativamente débiles, ya que las estimaciones obtenidas para la media y el intervalo de confianza al 95% mediante técnicas geostadísticas y técnicas clásicas coinciden. Los bajos valores de concentración de Pb detectados en C. crangon concuerdan con los datos obtenidos para crustáceos decápodos en otras regiones. Para Zn los valores medidos en otras regiones se encuentran de manera consistente por debajo del intervalo de confianza del 95%, mientras que para Cu los valores observados son ligeramente superiores a los nuestros. Para la concentración de Cd en C. crangon los valores que se indican en la literatura son claramente superiores a la concentraciones medidas en nuestro estudio, mientras que para Ni no existen valores de comparación. Se concluye que con esta aproximación integrada a la valoración biológica, las concentraciones de metales pueden evaluarse de manera más precisa, así como las relaciones entre variables bióticas y abióticas
Co-location of passive gear fisheries in offshore wind farms: Fairytale or future marine spatial planning approach?
Fishing within offshore wind farms in the North Sea:Stakeholder perspectives for multi-use from Scotland and Germany
Offshore wind power generation requires large areas of sea to accommodate its activities, with increasing claims for exclusive access. As a result, pressure is placed on other established maritime uses, such as commercial fisheries. The latter sector has often been taking a back seat in the thrust to move energy production offshore, thus leading to disagreements and conflicts among the different stakeholder groups. In recognition of the latter, there has been a growing international interest in exploring the combination of multiple maritime activities in the same area (multi-use; MU), including the re-instatement of fishing activities within, or in close proximity to, offshore wind farms (OWFs). We summarise local stakeholder perspectives from two sub-national case studies (East coast of Scotland and Germany's North Sea EEZ) to scope the feasibility of combining multiple uses of the sea, such as offshore wind farms and commercial fisheries. We combined a desk-based review with 15 semi-structured qualitative interviews with key knowledge holders from both industries, regulators, and academia to aggregate key results. Drivers, barriers and resulting effects (positive and negative) for potential multi-use of fisheries and OWFs are listed and ranked (57 factors in total). Factors are of economic, social, policy, legal, and technical nature. To date, in both case study areas, the offshore wind industry has shown little interest in multi-use solutions, unless clear added value is demonstrated and no risks to their operations are involved. In contrast, the commercial fishing sector is proactive towards multi-use projects and acts as a driving force for MU developments. We provide a range of management recommendations, based on stakeholder input, to support progress towards robust decision making in relation to multi-use solutions, including required policy and regulatory framework improvements, good practice guidance, empirical studies, capacity building of stakeholders and improvements of the consultation process. Our findings represent a comprehensive depiction of the current state and key stakeholder aspirations for multi-use solutions combining fisheries and OWFs. We believe that the pathways towards robust decision making in relation to multi-use solutions suggested here are transferable to other international locations
The Status of Coastal Benthic Ecosystems in the Mediterranean Sea: Evidence From Ecological Indicators
The Mediterranean Sea is subject to multiple human pressures increasingly threatening its unique biodiversity. Spatially explicit information on the ecological status of marine ecosystems is therefore key to an effective maritime spatial planning and management, and to help the achievement of environmental targets. Here, we summarized scientific data on the ecological status of a selection of marine ecosystems based on a set of ecological indicators in more than 700 sites of the Mediterranean Sea. For Posidonia oceanica seagrass beds, rocky intertidal fringe, and coastal soft bottoms, more than 70% of investigated sites exhibited good to high ecological conditions. In contrast, about two-thirds of sites for subtidal rocky reefs were classified to be in moderate to bad conditions, stressing the need for prioritizing conservation initiatives on these productive and diverse environments. Very little quantitative information was available
for the southern Mediterranean Sea, thus monitoring programs and assessments in
this area are essential for a representative assessment of the health of marine coastal
ecosystems in the whole basin. This overview represents a first step to implement a
baseline that, through georeferenced data on ecological status, could help identifying
information gaps, directing future research priorities, and supporting improvements to
spatial models of expected cumulative impacts on marine ecosystems
The Status of Coastal Benthic Ecosystems in the Mediterranean Sea: Evidence From Ecological Indicators
The Mediterranean Sea is subject to multiple human pressures increasingly threatening its unique biodiversity. Spatially explicit information on the ecological status of marine ecosystems is therefore key to an effective maritime spatial planning and management, and to help the achievement of environmental targets. Here, we summarized scientific data on the ecological status of a selection of marine ecosystems based on a set of ecological indicators in more than 700 sites of the Mediterranean Sea. For Posidonia oceanica seagrass beds, rocky intertidal fringe, and coastal soft bottoms, more than 70% of investigated sites exhibited good to high ecological conditions. In contrast, about two-thirds of sites for subtidal rocky reefs were classified to be in moderate to bad conditions, stressing the need for prioritizing conservation initiatives on these productive and diverse environments. Very little quantitative information was available for the southern Mediterranean Sea, thus monitoring programs and assessments in this area are essential for a representative assessment of the health of marine coastal ecosystems in the whole basin. This overview represents a first step to implement a baseline that, through georeferenced data on ecological status, could help identifying information gaps, directing future research priorities, and supporting improvements to spatial models of expected cumulative impacts on marine ecosystems
Position paper on lessons‐learned for the improvement of the generic concept and the necessary tools. Deliverable 3.4 of Project MESMA, Monitoring and Evaluation of Spatially Managed Areas, EU FP7
Challenges and Opportunities for Ecosystem-Based Management and Marine Spatial Planning in the Irish Sea
Ecosystem-Based Management (EBM) integrates the connections between land, air, water and all living things including human beings and their institutions. The location of the Irish Sea, between major historical industrial centres, its history of use and exploitation, combined with its hydrographic characteristics, have led to the current patterns of use. EBM efforts have been ongoing for over a decade but political boundaries have led to fragmented governance. The forthcoming UK exit from the European Union (EU) may pose further challenges. This chapter examines articulations between political boundaries, spatial scales of Marine Spatial Planning and nested social-ecological systems including the gyre in the western Irish Sea, and Dublin Bay. Examples of emerging best practices are provided and the challenges of data availability for ecosystem services are considered
Advancing marine conservation in European and contiguous seas with the MarCons Action
Cumulative human impacts have led to the degradation of marine ecosystems and the decline of biodiversity in the European and contiguous seas. Effective conservation measures are urgently needed to reverse these trends. Conservation must entail societal choices, underpinned by human values and worldviews that differ between the countries bordering these seas. Social, economic and political heterogeneity adds to the challenge of balancing conservation with sustainable use of the seas. Comprehensive macro-regional coordination is needed to ensure effective conservation of marine ecosystems and biodiversity of this region. Under the European Union Horizon 2020 framework programme, the MarCons COST action aims to promote collaborative research to support marine management, conservation planning and policy development. This will be achieved by developing novel methods and tools to close knowledge gaps and advance marine conservation science. This action will provide support for the development of macro-regional and national policies through six key actions: to develop tools to analyse cumulative human impacts; to identify critical scientific and technical gaps in conservation efforts; to improve the resilience of the marine environment to global change and biological invasions; to develop frameworks for integrated conservation planning across terrestrial, freshwater, and marine environments; to coordinate marine conservation policy across national boundaries; and to identify effective governance approaches for marine protected area management. Achieving the objectives of these actions will facilitate the integration of marine conservation policy into macro-regional maritime spatial planning agendas for the European and contiguous seas, thereby offsetting the loss of biodiversity and ecosystem services in this region
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