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Fleischer S 《Ambio》2003,32(1):2-5
Evidence is provided for an internal CO2 sink in forest soils, that may have a potential impact on the global CO2-budget. Lowered CO2 fraction in the soil atmosphere, and thus lowered CO2 release to the aboveground atmosphere, is indicated in high N-deposition areas. Also at forest edges, especially of spruce forest, where additional N-deposition has occurred, the soil CO2 is lowered, and the gradient increases into the closed forest. Over the last three decades the capacity of the forest soil to maintain the internal sink process has been limited to a cumulative supply of approximately 1000 and 1500 kg N ha(-1). Beyond this limit the internal soil CO2 sink becomes an additional CO2 source, together with nitrogen leaching. This stage of "nitrogen saturation" is still uncommon in closed forests in southern Scandinavia, however, it occurs in exposed forest edges which receive high atmospheric N-deposition. The soil CO2 gradient, which originally increases from the edge towards the closed forest, becomes reversed. 相似文献
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Andrea M. Hofmaier Siegfried M. G. Schwirzer Friedrich J. Wiebel Karl-Werner Schramm Martin Wegenke und Antonius A. F. Kettrup 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(1):2-8
Zusammenfassung Polychlorierte aromatische Kohlenwasserstoffe (PHAK), z.B. 2,3,7,8-Tetrachlordibenzo-p-dioxin (TCDD), weisen eine Vielzahl von toxischen Wirkungen und biologischen Effekten auf. Die Substanzklasse der PHAK besitzt
die Eigenschaft der Bindung an ein cytosolisches Rezeptor-Protein, gefolgt von der Synthese bestimmter Genprodukte, u.a. von
Cytochrom P450 1A1 (CYP 1A1). In dieser Arbeit wird ein Bioassay beschrieben, der erlaubt, die Induktion von CYP 1A1 als Summenparameter
für die biologische Wirksamkeit der kritischen, halogenierten Verbindungen in komplexen Umweltmatrizes zu bestimmen. Zur Abtrennung
von Substanzen aus den Extrakten von Umweltproben (z. B. Naturstoffe und polyzyklische aromatische Kohlenwasserstoffe), die
den Bioassay st?ren k?nnen, wurde ein Ein-S?ulen-Clean-up entwickelt. Die biologisch ermittelten TEQ-Werte stimmen gut mit
den Resultaten der chemischen Analytik überein. Der Bioassay in Kombination mit dem Clean-up bietet eine zeitsparende und
kostengünstige M?glichkeit zur Untersuchung von Umweltproben.
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Enrico Di Minin Christoph Fink Anna Hausmann Jens Kremer Ritwik Kulkarni 《Conservation biology》2021,35(2):437-446
Social media data are being increasingly used in conservation science to study human–nature interactions. User-generated content, such as images, video, text, and audio, and the associated metadata can be used to assess such interactions. A number of social media platforms provide free access to user-generated social media content. However, similar to any research involving people, scientific investigations based on social media data require compliance with highest standards of data privacy and data protection, even when data are publicly available. Should social media data be misused, the risks to individual users' privacy and well-being can be substantial. We investigated the legal basis for using social media data while ensuring data subjects’ rights through a case study based on the European Union's General Data Protection Regulation. The risks associated with using social media data in research include accidental and purposeful misidentification that has the potential to cause psychological or physical harm to an identified person. To collect, store, protect, share, and manage social media data in a way that prevents potential risks to users involved, one should minimize data, anonymize data, and follow strict data management procedure. Risk-based approaches, such as a data privacy impact assessment, can be used to identify and minimize privacy risks to social media users, to demonstrate accountability and to comply with data protection legislation. We recommend that conservation scientists carefully consider our recommendations in devising their research objectives so as to facilitate responsible use of social media data in conservation science research, for example, in conservation culturomics and investigations of illegal wildlife trade online. 相似文献
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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