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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   
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Evidence of diseases on vertebrate fossil bones can provide detailed information on many aspects of extinct animals. This study focused on pathological craniodental remains (left maxilla and dentary) referred to the canid Cuon alpinus unearthed from a Late Pleistocene karst filling deposit at San Sidero (Apulia, southern Italy). These fossils show clear evidence of a chronic periodontitis that caused the animal’s death. Clinical diagnosis of the disease and the timing of its development have been defined on the basis of a veterinary odontostomatology approach, in addition to radiographic and tomographic techniques. From the initiation of the infection until death, a time span of at least 6 months occurred, and three main steps have been defined: (1) the bacterial infections of the buccal cavity turning into severe periodontitis, (2) the fracture of the lower carnassial and (3) the loss of teeth due to the worsening infection that deformed and/or eroded maxillary and mandibular bones and enlarged alveoli. The analysis of the palaeopathology also provides information about the biomechanics of the bite, on the feeding behaviour and on the relationships of injured members in a pack of Late Pleistocene canids.  相似文献   
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Many new forms of water governance are emerging in response to economic and social needs and wants, as well as water-related problems such as scarcity, injustice, and conflict. However, there is little evidence on how sustainable these governance regimes are, which would be critical for making progress toward sustainable and just water governance. In this article, we present the results of a transdisciplinary multi-criteria sustainability assessment of alternative governance regimes for Guanacaste Province, Costa Rica. The assessment specifies differences between sustainable and unsustainable governance regimes, while also pinpointing how the current water governance regime performs in comparison to those alternatives. The findings indicate that those governance regimes with just and deliberative stakeholder involvement, secure groundwater reserves, and healthy dry tropical ecosystems were considered sustainable and just. In contrast, the current state of water governance was found to be at high risk of digressing toward unsustainable systems where rural communities lack rights and influence, where economies favor agro-industry and high impact tourism at the expense of rural livelihoods, and where water scarcity overwhelms weak governance. This assessment study clarifies water sustainability goals, asserts the need for transformational change, and offers a pragmatic foundation for actions toward sustainable water governance.  相似文献   
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In developing countries where economies and livelihoods depend largely on ecosystem services, policies for adaptation to climate change should take into account the role of these services in increasing the resilience of society. This ecosystem-based approach to adaptation was the focus of an international workshop on “Adaptation to Climate Change: the role of Ecosystem Services” held in November 2008 in Costa Rica. This article presents the key messages from the workshop.  相似文献   
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An extended Life Cycle Assessment (LCA) is performed for evaluating the impacts of a woody biomass supply chain for heating plants in the alpine region. Three main aspects of sustainability are assessed: greenhouse gas emissions, represented by global warming potential (GWP) impact category, costs and direct employment potential. We investigate a whole tree system (innovative logging system) where the harvest of logging residues is integrated into the harvest of conventional wood products. The case study is performed in Valle di Fiemme in Trentino region (North Italy) and includes theoretical and practical elements. The system boundary is the alpine forest fuel system, from logging operations at the forest stand to combustion of woody biofuels at the heating plant. The functional unit is 1 m3 solid over bark of woody biomass, delivered to the district heating plant in Cavalese (Trento). The relative sustainability of traditional and innovative systems is compared and energy use is estimated. Results show that the overall GWP and costs are about 13 kg CO2equivalent and 42 euro per functional unit respectively for the innovative system. Along the product supply chain, chipping contributes the greatest share of GWP and energy use, while extraction by yarder has the highest financial costs. The GWP is reduced by 2.3 ton CO2equivalent when bioenergy substitutes fuel oil and 1.7 ton CO2equivalent when it substitutes natural gas. The sensitivity analysis illustrates that variations in fuel consumption and hourly rates of costs have a great influence on chipping operation and extraction by cable yarder concerning GWP and financial analysis, respectively. This is confirmed by sensitivity analysis. Better technologies, the use of biofuels along the product supply chain and more efficient systems might reduce these impacts. Replacing the traditional system with the innovative one reduces emissions and costs. A low energy input ratio is required for harvesting logging residues. The direct employment potential is a conflicting aspect and needs further investigations.  相似文献   
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An integrated biomonitoring program for marine and coastal ecosystems quality assessment combines the chemical characterization of a site with the evaluation of the possible structure alterations of its living communities. This can be considered an useful tool for better identifying the summarized effects of all the components interacting with the biota. Such an integrated procedure was carried out for the assessment of the quality of the Lesina Lagoon (Southern Adriatic Coast, Italy). The water parameters levels showed a high primary production (2-6 μg l-1); the sediment and pore water toxicity bioassays recorded a low or moderate diffused toxicity. Besides, the benthic meiofauna community structure was characterized by prevalent Nematoda taxa with a homogeneous spatial distribution. On these basis, the Lesina Lagoon seems to be characterized by a prevalent organic pollution mainly related to agricultural and zootechnical activities which, due to the lagoon's conformation, presents a homogeneous spatial distribution.  相似文献   
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Background, aim and scope  

Landfill gas (LFG) tends to escape from the landfill surface even when LFG collecting systems are installed. Since LFG leaks are generally a noticeable percentage of the total production of LFG, the optimisation of the collection system is a fundamental step for both energy recovery and environmental impact mitigation. In this work, we suggest to take into account the results of direct measurements of gas fluxes at the air–cover interface to achieve this goal.  相似文献   
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