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31.
Duarte B  Reboreda R  Caçador I 《Chemosphere》2008,73(7):1056-1063
The influence of salt marsh sediment extracellular enzymatic activity (EEA) on metal fractions and organic matter cycling was evaluated on a seasonal basis, in order to study the relation between organic matter cycles and the associated metal species. Metals in the rhizosediment of Halimione portulacoides were fractioned according to the Tessier's scheme and showed a similar pattern regarding the organic-bound fraction, being always high in Autumn, matching the season when organic matter presented higher values. Both organic-bound and residual fractions were always dominant, being the seasonal variations due to interchanges between these two fractions. Phenol oxidase and beta-N-acetylglucosaminidase had higher activities during the Spring and Summer, contrarily to peroxidase which had higher activity during Winter. Protease showed high activities in both Spring and Winter. These different periods of high organic matter hydrolysis caused two periods of organic metal bound decrease. Sulphatase peaks (Spring and Winter) matched the depletion of exchangeable metal forms, probably due to sulphides formation and consequent mobilization. This showed an interaction between several microbial activities affecting metal speciation.  相似文献   
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33.
Sustainable labels are considered the best way for consumers to identify brands with environmental or social attributes on the shelves, and therefore promoted as a means to develop the so-called “ethical markets”. However, little is known about how consumers use these brands. This paper tries to offer complementary theoretical insights on the determinants of sustainable label use by drawing on the economic model of information search; in particular, it examines the influence of two factors on the purchase of such labels: motivation and knowledge. Information was gathered through a structured questionnaire in personal interviews with 289 primary buyers. The study found that education influences directly knowledge, while Motivation influences Label use both directly and indirectly, via Label knowledge. This study concludes that Motivation is the most powerful factor to explain Label use; knowledge is a necessary but not sufficient condition. Even more, consumers may not have a good understanding of sustainable labels and still use them in their purchasing decisions. This suggests that there is a dual processing mode of sustainable labels, both systematic and heuristic.  相似文献   
34.

Introduction

The Consolider-Ingenio 2010 project SCARCE, with the full title ??Assessing and predicting effects on water quantity and quality in Iberian Rivers caused by global change?? aims to examine and predict the relevance of global change on water availability, water quality, and ecosystem services in Mediterranean river basins of the Iberian Peninsula, as well as their socio-economic impacts. Starting in December 2009, it brought together a multidisciplinary team of 11 partner Spanish institutions, as well as the active involvement of water authorities, river basin managers, and other relevant agents as stakeholders.

Methods

The study areas are the Llobregat, Ebro, Jucar, and Guadalquivir river basins. These basins have been included in previous studies and projects, the majority of whom considered some of the aspects included in SCARCE but individually. Historical data will be used as a starting point of the project but also to obtain longer time series. The main added value of SCARCE project is the inclusion of scientific disciplines ranging from hydrology, geomorphology, ecology, chemistry, and ecotoxicology, to engineering, modeling, and economy, in an unprecedented effort in the Mediterranean area. The project performs data mining, field, and lab research as well as modeling and upscaling of the findings to apply them to the entire river basin.

Results

Scales ranging from the laboratory to river basins are addressed with the potential to help improve river basin management. The project emphasizes, thus, linking basic research and management practices in a single framework. In fact, one of the main objectives of SCARCE is to act as a bridge between the scientific and the management and to transform research results on management keys and tools for improving the River Basin Management Plans. Here, we outline the general structure of the project and the activities conducted within the ten Work Packages of SCARCE.  相似文献   
35.

Introduction  

A Microcoleus sp. consortium, obtained from the Ebro delta microbial mat, was maintained under different conditions including uncontaminated, lead-contaminated, and acidic conditions.  相似文献   
36.
Using the focusing event framework, a comprehensive analysis of private households’ and businesses’ preparedness was undertaken in the aftermath of the 2002 and 2006 flood events on the Elbe River in Germany. In August 2002, preparedness of households (n = 235) and businesses (n = 103) was low: 30% of the households and 54% of the businesses took no precautionary measures before the flood event. Many undertaken emergency measures were ineffective, since only 26% of all households knew how to react when the flood warning came, and only 9% of businesses had an emergency plan in place. Due to this extreme flood, double-loop learning occurred in many households and businesses, so that many did implement precautionary measures. The distribution of adopted precautionary measures for households fits well to Preisendörfer’s low-cost hypothesis, but does not apply for businesses. Only 10% of the households (n = 112), but still 29% of the businesses (n = 41) were unprepared before the flood in 2006. Significant improvement in flood preparedness activities is still necessary. Particularly for businesses, regulatory programs and programs encouraging proactive behaviour should be implemented. The focusing event framework proofed to be a useful tool for a differentiated analysis of the responses to and learning due to a disaster also in the commercial and private sector.  相似文献   
37.
The global urban population is increasing rapidly, but patterns of urban expansion differ greatly among countries. Urban transition theory predicts that the shift from low to high urbanization depends on a country’s history and level of economic development. This study describes urban expansion in Colombia, Ecuador, Peru, and Bolivia between 1992 and 2009. Urban dynamics were analyzed by combining nighttime lights and census data from 4032 municipalities. High-lit areas (>52–63 pixel values) were correlated with urban populations across municipalities and years (R 2 > 0.90). Analyses showed that between 1992 and 2009 Bolivia and Ecuador had rapid population growth and rapidly increasing high-lit areas, while Peru and Colombia had lower rates of population growth and urbanization (i.e., expansion of high-lit areas). We demonstrate how nighttime lights can be a useful tool, providing a homogeneous platform for multi-scale analyses of urban growth.  相似文献   
38.
Balanced reciprocal translocation is one of the known causes of recurrent spontaneous abortions. Cytogenetic studies of unbalanced miscarriages are difficult due to the growth failure of early loss and usually macerated abortions. We present a molecular study of an abortion in which the father carries a balanced reciprocal translocation t(2;17)(q32.1;q24.3) using QF-PCR and CGH techniques. DNA analysis showed the presence of a trisomy 2 due to a 3:1 interchange segregation. Recombinant events could also be investigated by comparing DNA samples from the family. We propose QF-PCR in addition to CGH as an efficient diagnostic method to improve our knowledge of unbalanced offspring in balanced translocation carriers. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
39.

Climate change is a global phenomenon that affects biophysical systems and human well-being. The Paris Agreement of the United Nations Framework Convention on Climate Change entered into force in 2016 with the objective of strengthening the global response to climate change by keeping global temperature rise this century well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 °C. The agreement requires all Parties to submit their “nationally determined contributions” (NDCs) and to strengthen these efforts in the years ahead. Reducing carbon emissions from deforestation and forest degradation is an important strategy for mitigating climate change, particularly in developing countries with large forests. Extensive tropical forest loss and degradation have increased awareness at the international level of the need to undertake large-scale ecological restoration, highlighting the need to identify cases in which restoration strategies can contribute to mitigation and adaptation. Here we consider Brazil as a case study to evaluate the benefits and challenges of implementing large-scale restoration programs in developing countries. The Brazilian NDC included the target of restoring and reforesting 12 million hectares of forests for multiple uses by 2030. Restoration of native vegetation is one of the foundations of sustainable rural development in Brazil and should consider multiple purposes, from biodiversity and ecosystem services conservation to social and economic development. However, ecological restoration still presents substantial challenges for tropical and mega-diverse countries, including the need to develop plans that are technically and financially feasible, as well as public policies and monitoring instruments that can assess effectiveness. The planning, execution, and monitoring of restoration efforts strongly depend on the context and the diagnosis of the area with respect to reference ecosystems (e.g., forests, savannas, grasslands, wetlands). In addition, poor integration of climate change policies at the national and subnational levels and with other sectorial policies constrains the large-scale implementation of restoration programs. The case of Brazil shows that slowing deforestation is possible; however, this analysis highlights the need for increased national commitment and international support for actions that require large-scale transformations of the forest sector regarding ecosystem restoration efforts. Scaling up the ambitions and actions of the Paris Agreement implies the need for a global framework that recognizes landscape restoration as a cost-effective nature-based solution and that supports countries in addressing their remaining needs, challenges, and barriers.

  相似文献   
40.
In a preceding study it has been reported that the freshwater sponge Lubomirskia baicalensis, living in Lake Baikal (East Siberia), is composed of spicules forming a characteristic pattern which follows radiate accretive growth. Here we report that the spicules are synthesized by the enzyme silicatein, a protein which is related to cathepsin L. The cDNAs for silicatein and the related cathepsin L were isolated and used as probes to show that the mRNA levels of silicatein in the bases of the spicule skeleton of the animals are low, while the mRNA level of cathepsin L in this region exceeds that of the growing zone. This is the first comprehensive study on the importance of the axial filament/silicatein as an essential structural and functional component determining the growth and stability of demosponge spicules.Note: Sequences from Lubomirskia baicalensis have been deposited in the EMBL/GenBank; cDNAs for the putative silicatein (LBSILICA) are deposited under the accession no. AJ786771 and for cathepsin L (LBCATL) under the accession no. AJ786770.  相似文献   
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