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21.
Characterization of water extractable organic matter in a deep soil profile   总被引:5,自引:0,他引:5  
The aim of this study was to identify qualitative and quantitative differences of water extractable organic matter (WEOM) isolated from each horizon along a deep soil profile and to evaluate any relationship between the WEOC and the total organic carbon (TOC) content. The soil profile "Monte Pietroso" is located in the Murge area, Apulia region in Southern Italy. Samples from the eight horizons (Ap1, Ap2, Ab1, Ab2, Bt1, 2B, 2Bt2, and 2B/C) were collected in October 2002. The WEOM characterization was carried out by means of UV absorbance, fluorescence spectroscopy in the emission and excitation/emission matrix (EEM) modes, and additional spectroscopic derived indexes. Soil organic carbon was shown to accumulate in the top horizons (Ap) and, in general, to decrease with depth, whereas, the WEOM/TOC ratio increases with increasing depth. The aromaticity and the humification index of the WEOM decrease dramatically downward the soil profile, whereas the fluorescence efficiency index tends to increase markedly. The WEOM fractions feature three main fluorophores with different wavelength and relative intensity. In general WEOM transport phenomena are suggested to occur downward the soil profile, depending on the nature of the organic material and on the chemical and mineral characteristics of the various horizons.  相似文献   
22.
One of the main limitations for a wider application of surfactants in soil remediation is the lack of knowledge about environmental fate and toxicity of surfactant itself especially for in situ application. Sorption behaviour, biodegradability, toxicity of parent compound and its metabolites are important processes that affect environmental fate of surfactants in site remediation applications. Tween 80 (poly(oxyethylene)(20)-sorbitane monooleate) and Aerosol MA+80 (dihexyl sodium sulfosuccinate) are surfactants that have been tested in laboratory and field scale remediation of soil and groundwater. In this work, the sorption and biodegradability of these surfactants were assessed to provide conditions and limitations for their use. The soil used in this experimentation was analysed for organic carbon content, soil bacteria, and size fraction and resulted to be a good model because is characterised by mean values for almost all considered parameters. Tween 80 showed high degree of biodegradability but a high affinity for soil matrix. Results suggest that Tween 80 could find its best application in ex situ solid phase remediation like ex situ bioremediation; its high affinity to soil could limit in situ applications. Biodegradation tests for Aerosol MA+80 show low degree of biodegradability and mineralisation. Biodegradation experiments, coupled with analysis of toxicity, could support the hypothesis that degradation of Aerosol MA+80 is not complete and leads to an accumulation of intermediates with at least the same toxicity of the parental compound. Therefore, aquifer remediation application with Aerosol MA+80 has to be conducted with necessary precautions to avoid product loss and excess surfactant should be flushed from the soil.  相似文献   
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The need for mental health resources to provide care to the community following large‐scale disasters is well documented. In the aftermath of the World Trade Center (WTC) disaster on September 11, 2001, many local agencies and organizations responded by providing informal mental health services, including disaster mental health training for practitioners. The quality of these programmes has not been assessed, however. The National Center for Disaster Preparedness at Columbia University's School of Public Health reviewed disaster mental health training programmes administered by community‐based organizations, professional associations, hospitals, and government agencies after September 11. Results indicate that the quality and the effectiveness of programmes are difficult to assess. A wide range of curricula and a widespread lack of recordkeeping and credentialing of trainers were noted. Most of the training programmes provided are no longer available. Recommendations for improving the quality of disaster mental health training programmes are provided.  相似文献   
25.
The Arctic is nutrient limited, particularly by nitrogen, and is impacted by anthropogenic global warming which occurs approximately twice as fast compared to the global average. Arctic warming intensifies thawing of permafrost-affected soils releasing their large organic nitrogen reservoir. This organic nitrogen reaches hydrological systems, is remineralized to reactive inorganic nitrogen, and is transported to the Arctic Ocean via large rivers. We estimate the load of nitrogen supplied from terrestrial sources into the Arctic Ocean by sampling in the Lena River and its Delta. We took water samples along one of the major deltaic channels in winter and summer in 2019 and sampling station in the central delta over a one-year cycle. Additionally, we investigate the potential release of reactive nitrogen, including nitrous oxide from soils in the Delta. We found that the Lena transported nitrogen as dissolved organic nitrogen to the coastal Arctic Ocean and that eroded soils are sources of reactive inorganic nitrogen such as ammonium and nitrate. The Lena and the Deltaic region apparently are considerable sources of nitrogen to nearshore coastal zone. The potential higher availability of inorganic nitrogen might be a source to enhance nitrous oxide emissions from terrestrial and aquatic sources to the atmosphere.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01665-0.  相似文献   
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Many vertebrates grow up in the company of same or different-age siblings, and relations among them can be expected to significantly influence individual life histories and the development of individual morphological, physiological, and behavioral phenotypes. Although studies in birds still dominate and have stimulated most theoretical considerations, the increasing number of mammalian studies promises to broaden our understanding of this complex field by enabling interesting comparisons with the rather different bird system. It therefore seems timely to bring together recent studies of sibling relations in mammals and to demonstrate what these can offer in the way of fresh insights. In this brief review, intended to accompany a series of papers on a diverse range of mammals, we outline the current state of sibling research in mammals, comparing it to the better studied birds. Most obviously, in mammals, mother and young are in much closer contact during early life than in birds, and siblings can influence each other’s development as well as the mother’s physiology while still in utero. During nursing, mammalian young also encounter a very different feeding situation to bird siblings. These contrasts should help stimulate further debate, as well as provide further opportunities to study the relative importance of maternal versus sibling effects on individual development. Finally, we discuss the need to balance studies of sibling competition and conflict with a consideration of the benefits accruing to individuals from sibling presence and the need for long-term studies of the influence of early sibling relations on individual development and life histories. This contribution represents the introduction to the special issue “Sibling competition and cooperation in mammals”.  相似文献   
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The Australian environment and agriculture is suffering from land degradation and declining biodiversity. Laws protecting native vegetation are aimed at addressing these problems but have been resisted by farmers, compromising the social agreement necessary for regulatory success. A case study drawing on farmer interviews in central northern New South Wales reveals that the laws are considered to be under-achieving environmental outcomes since they are ill-suited to local conditions. The low feasibility of the rules is also undermining rule and state legitimacy. Regulatory resistance is due to the lack of recognition of place-specifics by government and laws that impose universal requirements. There is an epistemic distance between the bureaucratic knowledge held by government and the vernacular knowledge (place-based knowledge) of heterogeneous environments held by farmers. Incorporating vernacular knowledge so that laws are more geographically sympathetic may close vernacular disjunctures and cure regulatory failure.  相似文献   
29.
China has made some remarkable achievements in sustainable development,but the constant deterioration of the overall trend of the environment has not yet been effectively curbed.To achieve the goal of sustainable development,we must first ensure coordination and coherence of national development goals in different areas and adhere to green development road.To achieve the objectives related to green development,and to clarify the direction of green development in the next 20years,a road map is needed to guide and coordinate the process.This paper describes the concept of the green development road map,introduces a green development road map for the western region,and further elaborates it The road map clarifies the objectives and guiding principles of green development in the western region,points the areas that deserve more concern and institutional innovation,and builds a green development monitoring and evaluation(M&E)framework.Finally,the paper provides corresponding policy recommendations based on the established road map.  相似文献   
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