Marine quality assessment by use of benthic species-abundance distributions: a proposed new protocol within the European Union Water Framework Directive   总被引：3，自引：0，他引：3  

Rosenberg R  Blomqvist M  C Nilsson H  Cederwall H  Dimming A 《Marine pollution bulletin》2004,49(9-10):728-739

The aim of this study is to develop a new method for classification of marine benthic quality according to the European Union Water Framework Directive. Tolerance values to environmental disturbance were determined in an objective analysis for benthic species along the Swedish west coast by using 4676 samples from 257 stations. Based on a combination of the species tolerance values, abundance and diversity, a benthic quality index (BQI) was calculated for the assessment of environmental status at a particular station. The qualification of BQI was evaluated in relation to known spatial and temporal gradients of disturbance.  相似文献   

A uniform terminology on bioinvasions: a chimera or an operative tool?   总被引：4，自引：0，他引：4  

Occhipinti-Ambrogi A  Galil BS 《Marine pollution bulletin》2004,49(9-10):688-694

A consensual set of definitions regarding bioinvasions is essential in order to facilitate discourse among the science, policy and management communities dealing with the issue. Considering both the mode of entry and the extent of the impact of an alien species into a new environment, a set of key terms is proposed as an operative tool for marine scientists.  相似文献   

A simulation of Asian dust events in March 2010 by using the ADAM2 model     

Soon-Ung Park  Anna Choe  Moon-Soo Park 《Theoretical and Applied Climatology》2012,107(3-4):491-503

Asian dust events occurred in Asia during March 2010 were simulated using the Asian Dust Aerosol Model 2 (ADAM2). The performance of the model for simulations of surface dust concentrations and dust event occurrences was tested at several monitoring sites located in the dust source region and the downstream region of Korea. The observed and modeled dust event occurrences at each monitoring site were defined with the hourly observed and modeled dust concentrations that were used to evaluate the performance of the model by constructing a contingency table for the dust event occurrence. It was found that the model simulated quite well the starting and ending times of dust events with their peak dust concentrations for most dust events occurred both in the dust source region and the downstream region of Korea. However, the model failed to simulate a few dust events observed in both regions mainly due to the inaccurate simulations of the meteorological fields. Inaccurate simulations of wind speeds have caused for the model to simulate dust events poorly in the dust source region whereas poor simulations of precipitation of the fifth-generation mesoscale model (MM5) model have led to miss dust events in the downstream region of Korea. The contingency table made with the hourly data for the dust event occurrence made it possible to evaluate the ADAM2 model for the simulation of the dust event occurrence. It was found that the model has the probabilistic simulation capability for dust events of about 78% with the hit rate of more than 83% and the false alarm rate of about 27% for the dust events occurred during March in 2010. The probabilistic capability of the model could be much improved by improving the meteorological model (MM5 model).  相似文献   

The Asian Dust Aerosol Model 2 (ADAM2) with the use of Normalized Difference Vegetation Index (NDVI) obtained from the Spot4/vegetation data   总被引：1，自引：0，他引：1  

Soon-Ung Park  Anna Choe  Eun-Hee Lee  Moon-Soo Park  Xingzhuo Song 《Theoretical and Applied Climatology》2010,101(1-2):191-208

The operational Asian Dust Aerosol Model (ADAM)1 in Korea Meteorological Administration has been modified to the ADAM2 model to be used as an operational forecasting model all year round not only in Korea but also in the whole Asian domain (70-160°E and 5-60°N) using the routinely available World Meteorological Organization (WMO) surface reporting data and the Spot/vegetation Normalized Difference Vegetation Index (NDVI) data for the period of 9 years from 1998 to 2006. The 3-hourly reporting WMO surface data in the Asian domain have been used to re-delineate the Asian dust source region and to determine the temporal variation of the threshold wind speed for the dust rise. The dust emission reduction factor due to vegetation in different surface soil-type regions (Gobi, sand, loess, and mixed soil) has been determined with the use of NDVI data. It is found that the threshold wind speed for the dust rise varies significantly with time (minimum in summer and maximum in winter) and surface soil types with the highest threshold wind speed of 8.0 m?s^?1 in the Gobi region and the lowest value of 6.0 m?s^?1 in the loess region. The statistical analysis of the spot/vegetation NDVI data enables to determine the emission reduction factor due to vegetation with the free NDVI value that is the NDVI value without the effect of vegetation and the upper limit value of NDVI for the dust rise in different soil-type regions. The modified ADAM2 model has been implemented to simulate two Asian dust events observed in Korea for the periods from 31 March to 2 April 2007 (a spring dust event) and from 29 to 31 December 2007 (a winter dust event) when the observed PM₁₀ concentration at some monitoring sites in the source region exceeds 9,000 μg m^?3. It is found that ADAM2 model successfully simulates the observed high dust concentrations of more than 8,000 μg m^?3 in the dust source region and 600 μg m^?3 in the downstream region of Korea. This suggests that ADAM2 has a great potential for the use of an operational Asian dust forecast model in the Asian domain.  相似文献   

A three-tiered approach to participatory vulnerability assessment in the Solomon Islands   总被引：1，自引：0，他引：1  

Ioan Fazey  Mike Kesby  Anna Evely  Ian Latham  Daniel Wagatora  Jude-Edward Hagasua  Mark S. Reed  Mike Christie 《Global Environmental Change》2010,20(4):713-728

Greater recognition of the seriousness of global environmental change has led to an increase in research that assesses the vulnerability of households, communities and regions to changing environmental or economic conditions. So far, however, there has been relatively little attention given to how assessments can be conducted in ways that help build capacity for local communities to understand and find their own solutions to their problems. This paper reports on an approach that was designed and used to work with a local grass roots organization in the Solomon Islands to promote inclusivity and participation in decision-making and to build the capacity of the organization to reduce the vulnerability of communities to drivers of change. The process involved working collaboratively with the organization and training its members to conduct vulnerability assessments with communities using participatory and deliberative methods. To make best use of the learning opportunities provided by the research process, specific periods for formal reflection were incorporated for the three key stakeholders involved: the primary researchers; research assistants; and community members. Overall, the approach: (1) promoted learning about the current situation in Kahua and encouraged deeper analysis of problems; (2) built capacity for communities to manage the challenges they were facing; and (3) fostered local ownership and responsibility for problems and set precedents for future participation in decision-making. While the local organization and the communities it serves still face significant challenges, the research approach set the scene for greater local participation and effort to maintain and enhance livelihoods and wellbeing. The outcomes highlight the need for greater emphasis on embedding participatory approaches in vulnerability assessments for communities to benefit fully from the process.  相似文献   

The STAGES view of red spirals and dusty red galaxies: mass-dependent quenching of star formation in cluster infall     

Christian Wolf  Alfonso Aragón-Salamanca  Michael Balogh  Marco Barden  Eric F. Bell  Meghan E. Gray  Chien Y. Peng  David Bacon  Fabio D. Barazza  Asmus Böhm  John A. R. Caldwell  Anna Gallazzi  Boris Häußler  Catherine Heymans  Knud Jahnke  Shardha Jogee  Eelco van Kampen  Kyle Lane  Daniel H. McIntosh  Klaus Meisenheimer  Casey Papovich  Sebastian F. Sánchez  y Taylor  Lutz Wisotzki  Xianzhong Zheng 《Monthly notices of the Royal Astronomical Society》2009,393(4):1302-1323

We investigate the properties of optically passive spirals and dusty red galaxies in the A901/2 cluster complex at redshift ∼0.17 using rest-frame near-ultraviolet–optical spectral energy distributions, 24-μm infrared data and Hubble Space Telescope morphologies from the STAGES data set. The cluster sample is based on COMBO-17 redshifts with an rms precision of  σ _cz ≈ 2000 km s⁻¹  . We find that 'dusty red galaxies' and 'optically passive spirals' in A901/2 are largely the same phenomenon, and that they form stars at a substantial rate, which is only four times lower than that in blue spirals at fixed mass. This star formation is more obscured than in blue galaxies and its optical signatures are weak. They appear predominantly in the stellar mass range of  log  M _*/M_⊙=[10, 11]  where they constitute over half of the star-forming galaxies in the cluster; they are thus a vital ingredient for understanding the overall picture of star formation quenching in clusters. We find that the mean specific star formation rate (SFR) of star-forming galaxies in the cluster is clearly lower than in the field, in contrast to the specific SFR properties of blue galaxies alone, which appear similar in cluster and field. Such a rich red spiral population is best explained if quenching is a slow process and morphological transformation is delayed even more. At  log  M _*/M_⊙ < 10  , such galaxies are rare, suggesting that their quenching is fast and accompanied by morphological change. We note that edge-on spirals play a minor role; despite being dust reddened they form only a small fraction of spirals independent of environment.  相似文献   

The rise and fall of galaxy activity in dark matter haloes     

Anna Pasquali  Frank C. van den Bosch  H. J. Mo  Xiaohu Yang  Rachel Somerville 《Monthly notices of the Royal Astronomical Society》2009,394(1):38-50

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Pedogenetic processes coeval with Neogene faults evolution in the Barcelona's Plain,NE Spain     

Irene Cantarero  Anna Travé  Gemma Alías 《Journal of Geochemical Exploration》2009

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The Method of Measurements of Celestial Coordinates in Wide-Field TV-Frames     

Anna P. Kartashova 《Earth, Moon, and Planets》2012,108(3-4):165-173

We present a method for calculations of equatorial coordinates of any point in the single frame of the wide-field TV systems. This method can be applying for the different television systems [wide-field cameras, all-sky cameras, the cameras with the hybrid TV-system (the system with coupled of the Image Intensifier) et al.]. In that system the calculations of distortions are difficult. Therefore, we devised this method which helps decrease errors (due to distortion and the electro-optical system).The method can be used for measuring of equatorial coordinates of meteor tracks under difficult conditions during the observations such as partial cloudiness, small number of stars and large distortions of the coordinate grid in the frame. These restrictions cannot be overcome by other methods. In the case of the small number of stars the present method using of the reference stars received on a series of frames during the observation period. The accuracy of the method has been estimated to be 4′–8′ (for cameras with fov 50°?×?40° at the CCD 720?×?576 pixels) for maximum number of reference points in the frame. The method used 3 reference points for calculation of the equatorial coordinates of the object. One can use this method if the camera was re-oriented as well. We use this method for our wide field of view cameras.  相似文献   

Subarctic catchment water storage and carbon cycling – Leading the way for future studies using integrated datasets at Pallas,Finland     

Hannu Marttila  Annalea Lohila  Pertti Ala-Aho  Kashif Noor  Jeffrey M. Welker  Danny Croghan  Kaisa Mustonen  Leo-Juhani Meriö  Anna Autio  Filip Muhic  Hannah Bailey  Mika Aurela  Jussi Vuorenmaa  Timo Penttilä  Valtteri Hyöky  Eric Klein  Anton Kuzmin  Pasi Korpelainen  Timo Kumpula  Anssi Rauhala  Bjørn Kløve 《水文研究》2021,35(9):e14350

Subarctic ecohydrological processes are changing rapidly, but detailed and integrated ecohydrological investigations are not as widespread as necessary. We introduce an integrated research catchment site (Pallas) for atmosphere, ecosystems, and ecohydrology studies in subarctic conditions in Finland that can be used for a new set of comparative catchment investigations. The Pallas site provides unique observational data and high-intensity field measurement datasets over long periods. The infrastructure for atmosphere- to landscape-scale research in ecosystem processes in a subarctic landscape has recently been complemented with detailed ecohydrological measurements. We identify three dominant processes in subarctic ecohydrology: (a) strong seasonality drives ecohydrological regimes, (b) limited dynamic storage causes rapid stream response to water inputs (snowmelt and intensive storms), and (c) hydrological state of the system regulates catchment-scale dissolved carbon dynamics and greenhouse (GHG) fluxes. Surface water and groundwater interactions play an important role in regulating catchment-scale carbon balances and ecosystem respiration within subarctic peatlands, particularly their spatial variability in the landscape. Based on our observations from Pallas, we highlight key research gaps in subarctic ecohydrology and propose several ways forward. We also demonstrate that the Pallas catchment meets the need for sustaining and pushing the boundaries of critical long-term integrated ecohydrological research in high-latitude environments.  相似文献