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171.
Rui Rosa Marta S. Pimentel Miguel Baptista Katja Trübenbach Ricardo Calado Maria L. Nunes Ana Moreno João Pereira 《Marine Biology》2013,160(2):263-275
The present study provides a comprehensive analysis of the biochemical composition (proximate composition, amino acids and fatty acids in gonad, digestive gland and muscle) of the cirrate octopod, Opisthoteuthis calypso, collected off the coast of Portugal. Protein and energy contents of O. calypso were significantly lower (p < 0.05) than those observed for coastal octopods, suggesting that the gelatinous musculature of the cirrate octopus may not be a direct consequence of food limitation, but rather associated with reduced selective pressure for strong swimming ability in the deep sea. Moreover, principal component analyses of fatty acid (FA) data clearly separated coastal octopods from O. calypso. Saturated FA biomarkers (namely 16:0, 17:0, 18:0) and monounsaturated FA 22:1 suggest a higher phytodetrital influence on diet of O. calypso. A clear separation between groups was also observed with amino acid (AA) data. However, essential AA and non-essential AA designations (based on the flow of carbon through biochemical systems) do not necessarily provide an accurate picture of the origins of amino nitrogen in the deep-sea environment. Consequently, the interpretation of the present data is a challenging task but opens a new window of opportunity to unravel new trophic biomarkers in the deep sea. 相似文献
172.
Bailey H Benson SR Shillinger GL Bograd SJ Dutton PH Eckert SA Morreale SJ Paladino FV Eguchi T Foley DG Block BA Piedra R Hitipeuw C Tapilatu RF Spotila JR 《Ecological applications》2012,22(3):735-747
Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of leatherback turtles within both coastal and pelagic areas means they have a high risk of exposure to many different fisheries, which may be very distant from their nesting sites. The EP leatherbacks have more limited foraging grounds than the WP leatherbacks, which could make them more susceptible to any temperature or prey changes that occur in response to climate change. 相似文献
173.
174.
Goldstein Gary A. DeLaquil Pat Sikharulidze Anna Monroy Angela Ines Cadena Cadena Ricardo Delgado Charpentier Silvia De Leon Felipe Meza Andrea Suphachalasai Suphachol Rodriguez Marcos Castro 《Environmental Modeling and Assessment》2021,26(6):927-946
Environmental Modeling & Assessment - Costa Rica has set a very ambitious Nationally Determined Contribution (NDC). Despite the low-carbon footprint of its power sector, the goal set in its NDC... 相似文献
175.
Ricardo A. Correia Richard Ladle Ivan Jarić Ana C. M. Malhado John C. Mittermeier Uri Roll Andrea Soriano-Redondo Diogo Veríssimo Christoph Fink Anna Hausmann Jhonatan Guedes-Santos Reut Vardi Enrico Di Minin 《Conservation biology》2021,35(2):398-411
Ongoing loss of biological diversity is primarily the result of unsustainable human behavior. Thus, the long-term success of biodiversity conservation depends on a thorough understanding of human–nature interactions. Such interactions are ubiquitous but vary greatly in time and space and are difficult to monitor efficiently at large spatial scales. However, the Information Age also provides new opportunities to better understand human–nature interactions because many aspects of daily life are recorded in a variety of digital formats. The emerging field of conservation culturomics aims to take advantage of digital data sources and methods to study human–nature interactions and thus to provide new tools for studying conservation at relevant temporal and spatial scales. Nevertheless, technical challenges associated with the identification, access, and analysis of relevant data hamper the wider adoption of culturomics methods. To help overcome these barriers, we propose a conservation culturomics research framework that addresses data acquisition, analysis, and inherent biases. The main sources of culturomic data include web pages, social media, and other digital platforms from which metrics of content and engagement can be obtained. Obtaining raw data from these platforms is usually desirable but requires careful consideration of how to access, store, and prepare the data for analysis. Methods for data analysis include network approaches to explore connections between topics, time-series analysis for temporal data, and spatial modeling to highlight spatial patterns. Outstanding challenges associated with culturomics research include issues of interdisciplinarity, ethics, data biases, and validation. The practical guidance we offer will help conservation researchers and practitioners identify and obtain the necessary data and carry out appropriate analyses for their specific questions, thus facilitating the wider adoption of culturomics approaches for conservation applications. 相似文献
176.
Gerald C. Blount Cathleen C. Caldwell Joao E. Cardoso‐Neto Karen R. Conner G. T. Jannik Charles E. Murphy David C. Noffsinger Jeff A. Ross 《补救:环境净化治理成本、技术与工艺杂志》2002,12(3):43-61
Natural remediation is moving toward the forefront as engineers clean groundwater at the Savannah River Site (SRS), a major Department of Energy (DOE) installation near Aiken, South Carolina. This article reviews two successful, innovative remediation methods currently being deployed: biosparging to treat chlorinated solvents and phytoremediation to address tritium in groundwater. The biosparging system reintroduces oxygen into the groundwater and injects nutrient compounds for in‐situ remediation. The system has greatly reduced the concentrations of trichloroethylene (TCE) and vinyl chloride in wells downgradient from a sanitary landfill (SLF). Phytoremediation is an emerging technology that promises effective and inexpensive cleanup of certain hazardous wastes. Using natural processes, plants can break down, trap and hold, or transpire contaminants. This article discusses the use of phytoremediation to reduce the discharge of tritium to an on‐site stream at SRS. © 2002 Wiley Periodicals Inc. * 相似文献
177.
Geraldo Da Silva e Souza Ricardo Coelho De Faria Tito Belchior S. Moreira 《Journal of the American Water Resources Association》2007,43(5):1237-1244
Abstract: This paper assesses cost efficiencies of Brazilian public and private companies of water supply. To measure the efficiency, we used a stochastic frontier model derived from the translog family – a specification similar to a Cobb‐Douglas including a quadratic term in log output. The model parameters are estimated by maximum likelihood using Brazilian data for the year 2002. Statistical inference leads to the conclusion that there is no evidence that private firms and public firms are significantly different in terms of efficiency measurements. 相似文献
178.
Angéline?BertinEmail author Victor?H.?Ruíz Ricardo?Figueroa Nicolas?Gouin 《Die Naturwissenschaften》2012,99(3):225-232
Wildlife data often show spatial organization, demonstrating positive correlations either as a result of processes occurring
over the landscape or due to the influence of spatially structured environmental variables. It is, thus, essential to consider
non-random spatial structure when evaluating the underlying causes of biological variation. In this study, we analyzed the
population structure of Chilina dombeyana shell morphology of 14 populations that are close geographically and belong to the same hydrographic basin. We utilized a
variation partitioning approach to evaluate the importance of spatial processes, such as migration, acting over the landscape,
and environmental characteristics, including habitat and hydrologic characteristics, and the occurrence of aquatic predators
in promoting between population variation. Our results demonstrate spatially structured variation in C. dombeyana shell morphology, with populations living near each other having more similar shell sizes than populations living farther
apart. The shell size variation partition indicated that both spatially structured environmental factors and genetic relationships
resulting from migration or shared common ancestry may explain this pattern. Shell shape variation, in contrast, was found
to be essentially under the influence of non-spatially structured environmental factors, with habitat and water characteristics
accounting for about half of the total variation among populations. The large proportion of the variation in shell size that
is spatially structured demonstrates that spatial structure on morphological traits might be strong and highlights the need
to consider such phenomenon in intraspecific studies of phenotypic evolution. 相似文献
179.
Ricardo Diaz‐Diaz Keith Loague 《Journal of the American Water Resources Association》2000,36(4):823-832
ABSTRACT: Agriculture is the leading cause of regional‐scale non‐point source (NPS) pollution in the world today. Indices of pesticide leaching in the vadose zone are well suited for estimating the spatial accumulation and distribution of NPS pollutants in the near surface. In this study the Attenuation Factor (AF) and the Leaching index (Li) are used to assess the near‐surface leaching potential for 32 important agrochemicals for world average agricultural soil properties and recharge rates. The AF and Li indices both require the same input data and appear to work well for nonpolar chemicals. In the effort reported here the AF and Li indices produced similar results for the 32 agrochemicals. Pesticides with high and moderate leaching potential are identified. The AF estimates were more constant than the Li estimates for changes in the compliance depth and recharge rate. The AF index is simpler to use than the Li index and, therefore, is more likely to be employed in the future for screening/ranking agrochemicals relative to regional‐scale NPS ground water vulnerability. 相似文献
180.
The spatial distribution of phytoplankton assemblages, chlorophyll, primary production and physical and chemical parameters were studied in the Pontevedra Ria in Galicia (NW Iberian Peninsula) from October 1997 to October 1998. In addition to the usual oceanographic periods described for the Galician Coast, two other periods were observed: a Prebloom or winter bloom, occurring during calm, sunny days in winter and a Continental period, related to the allochthonous intrusion of low salinity water from the Miño River in late spring. The phytoplankton biomass and production in both periods reached values of up to 145 mgChl-a m?2 and 3.6 gC m?2 day?1, respectively, which were similar to those found in summer upwelling blooms. Throughout the year, the phytoplankton biomass and primary production gradients along the ria’s axis were highly dependent on the balance between upwelling and runoff. When the latter prevailed, increased values were measured toward the inner ria, while the opposite pattern was observed during summer upwelling blooms. According to projections derived from climate models and the analysis of wind patterns, temperature and precipitation trends in the area, a drop in the productivity of the ria would be expected as a result of reduced upwelling intensity in summer and decreasing rainfall in spring. In any case the estuarine part of the ria would be the most seriously affected. 相似文献