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991.
Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants’ ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants’ rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results.  相似文献   
992.
Ecological and biological characteristics of Cyclachaena xanthiifolia (Nutt.) Fresen., have been studied in four regions of the Southern Urals and Cisural region. Communities including this species have been attributed to association Ivetum xanthiifoliae Fija?kowski 1967 of the class Stellarietea mediae R.Tx., Lohmeyer et Preising 1950. It has been shown that ecological habitat conditions have a significant effect on the majority of morphometric parameters of C. xanthiifolia, accounting for 1.3 to 51.4% of their total variance. Seed production averages 6500 seeds per plant. Extensive dispersal of the species over the Southern Ural region is predicted.  相似文献   
993.
Research in the area of media coverage on climate change communication represents one of the most prolific areas of inquiry within communication and mass communication studies. This body of literature, which ranges from empirical to critical studies, continues to expand. Much research has focused on representations of climate change causes, effects, and human actions, while some has assessed the impacts of these representations. What is broadly missing from this literature, however, is a discussion of how we might integrate media analysis into transdisciplinary collaborative research aimed at creating solutions to the social, environmental, and economic issues intertwined with climate change. Given the magnitude of problems the society and science are currently grasping with, it behooves us to understand how media studies can contribute most effectively to characterizing and solving problems. We maintain that the move toward integrating media studies into transdisciplinary collaborative research marks an essential transition for environmental communication in general, but climate change communication in particular, given the urgency and magnitude of creating meaningful adaptation and mitigation strategies to address this pressing, complex challenge. Drawing on our work as part of a large transdisciplinary sustainability science team, we provide a case study for understanding what collaborations are key to moving media studies into a transdisciplinary context and the key opportunities and barriers that come along with that move. We argue that media studies must increasingly engage directly in collaboration with other researchers, stakeholders, and communities to serve on-the-ground decision-making and enhance society's ability to take action.  相似文献   
994.
One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data‐deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data‐deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data‐deficient assessments. To develop this, we reviewed 2879 data‐deficient assessments in 6 animal groups and identified 8 main justifications for assigning data‐deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data‐deficient species slipping unnoticed toward extinction.  相似文献   
995.
This study deals with the question of how winegrowing in Spain may be altered by anthropogenic climate change. The present state and expected future development of three bioclimatic indices relevant for winegrowing were assessed by observation, and four regional climate models from the EU-ENSEMBLES project were investigated. When comparing the 2061–2090 scenario period to the 1961–1990 reference period, the models unanimously indicate a significant increase in the mean of the two considered thermal indices over the entire study region. However, for the index based on temperature and precipitation, the models are heavily biased when verified against observations and generally disagree on the size of the projected future change. For this index, unanimous model agreement was only found for northwestern Spain where all models indicated a significant decrease in the mean. From these results, regional climate change is expected to negatively affect the quality of wine in the growing regions of central and southern Spain, and the Ebro valley, whereas positive effects should be expected in the northwest. No significant changes in the risk of mildew infestation are to be expected except for the northwest, where this risk is projected to decrease.  相似文献   
996.
Mercury is a well-known toxic element, and flue gas streams emitted from coal-fired utilities are one of the largest anthropogenic sources of this element. This study briefly reviews the proposed technologies for reducing mercury emissions from coal combustion, focusing on an emerging process which involves the use of regenerable sorbents and especially those loaded with noble metals. Among the mercury species formed during coal combustion, elemental mercury is the most difficult to remove from the flue gases due to its low reactivity and insolubility in water. The widespread interest in using regenerable sorbents with metals is due to their ability to retain elemental mercury. With this technology, not only can efficiencies of 100 % be reached in the retention of elemental mercury but also a way to avoid the generation of new wastes loaded with mercury. This study considers the main aspects that must be taken into account when developing effective regenerable sorbents for mercury capture, with special attention to sorbents containing noble metals. The characteristics of this process are compared with those of other processes in a more advanced state of development.  相似文献   
997.
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999.
Nematode communities in the rooted soil layer under the crowns of introduced tree species on Valaam Island (Republic of Karelia) have been studied by conventional nematological methods to evaluate their taxonomic diversity, population density, and eco-trophic structure. On the whole, 49 nematode genera have been recorded, with their total abundance varying from 1209 to 2548 ind./100 g soil. The abundance and proportion of plant parasites in the soil nematode assemblage have proved to be higher under introduced trees, compared to natural forest biocenoses.  相似文献   
1000.
We develop a landscape stewardship classification which distinguishes between farmers’ understanding of landscape stewardship, their landscape values, and land management actions. Forty semi-structured interviews were conducted with small-holder (<5 acres), medium-holders (5–100 acres), and large-holders (>100 acres) in South-West Devon, UK. Thematic analysis revealed four types of stewardship understandings: (1) an environmental frame which emphasized the farmers’ role in conserving or restoring wildlife; (2) a primary production frame which emphasized the farmers’ role in taking care of primary production assets; (3) a holistic frame focusing on farmers’ role as a conservationist, primary producer, and manager of a range of landscape values, and; (4) an instrumental frame focusing on the financial benefits associated with compliance with agri-environmental schemes. We compare the landscape values and land management actions that emerged across stewardship types, and discuss the global implications of the landscape stewardship classification for the engagement of farmers in landscape management.  相似文献   
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