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231.
Soil erosion and associated off-site environmental impacts have attracted increasing attention in recent decades, and there is a growing need for reliable information on rates of soil loss. The potential for using 137Cs fallout to quantify rates and patterns of soil redistribution over medium-term timescales (ca. 45 years) has been successfully demonstrated in a wide range of environments around the world. The similar behaviour of fallout 210Pb in soils offers potential for its use as an alternative to 137Cs, in areas where 137Cs inventories are low or are complicated by additional fallout from the Chernobyl accident. There have, however, to date been few attempts to validate the use of fallout 210Pb measurements for assessing erosion rates. This paper reports an attempt to explore the use of fallout 210Pb to estimate rates of water-induced soil erosion on uncultivated land. It focuses on three small forest/rangeland catchments located in Calabria, southern Italy, for which measurements of sediment output are available. Comparison of the estimates of net soil loss from the catchments derived from 210Pb measurements with the measured sediment output, confirmed the validity of the 210Pb approach. The soil redistribution rates estimated using 210Pb measurements were also consistent with equivalent estimates obtained for the same study catchments using 137Cs measurements.  相似文献   
232.
Ecological Footprint Analysis (EFA) is an environmental accounting system, in physical unit, able to quantify the total amount of ecosystem resources required by a region or by a production process. This methodology is both scientifically robust and widely diffused for territorial and productive analysis. The application of EFA to agricultural systems are still uncommon and examples in the fruit sector rare.In this work a detailed application of EFA to an experimental trial in a commercial nectarine orchard in Piedmont (Italy) is presented. The field trial is focused on the evaluation of agronomical benefit of various kinds of swine manure for fertilizing orchards. Four productive systems were established from 2008: liquid slurry (LS), covered slurry (CS), solid fraction (SF), mineral nutrition (MN). All the environmental impacts of the four systems were quantified both directly on field and with extrapolations from farmer knowledge. As previous studies suggested, we considered not only the one-year field operations, but also the whole lifetime of the orchard. The environmental costs of each system are presented and related to each other on the basis of their relative footprint value.Results highlight almost the same ecological footprint for the three manure fertilized systems (LS, CS and SF) with average of 0.96 gha t−1) and the highest ecological footprint can be found in the MN system (1.14 gha t−1). Interesting remarks can be done comparing the contributions to the ecological footprint of the field operations related to fertilization in the four systems. In the manure fertilized systems the fertilizer contribution goes from 0.9% to 1.2% of the total ecological footprint; but in the MN system the fertilizer contribution is 6.6% of the total ecological footprint. Results support the hypothesis that internal recycle and connections among different systems increasingly resulted in high system benefit and sustainability.  相似文献   
233.
The current paper discusses the topic of marine storm impact along European coastlines, presenting results from two FP7 Projects currently focusing on this topic, one working on the physical aspects of the problem (MICORE) and the other one on the socio-economic implications (ConHaz).The MICORE Project aims to provide on-line predictions of storm-related physical hazards (hydrodynamic as well as morphodynamic). The ConHaz Project addresses the socio-economic implications should these (or other) hazards actually materialize. Together these projects aim to deliver crucial information for emergency response efforts, while realizing the practical limitations for information processing and dissemination during crisis situations.The MICORE Project has developed and demonstrated on-line tools for reliable predictions of the morphological impact of marine storm events in support of civil protection mitigation strategies. The project specifically targeted the development of early warning and information systems to support short term emergency response in case of an extreme storm event. The current paper discusses in detail the outcome of an activity of databasing historical storm data. No clear changes in storminess were observed, except for some storm proxies (e.g. surges) and only at some locations (e.g. northern Adriatic, southern Baltic, etc.).The ConHaz Project undertook a desktop study of the methods normally used for evaluating the impact of marine storms and the associated coastal hazards considering direct costs, costs due to disruption of production processes, indirect costs, intangible costs, and costs of adaptation and mitigation measures. Several methods for cost estimation were reviewed. From the review it emerged that normally end-users only evaluate direct costs after the storms, while the cost of adaptation and mitigation measures is only done strategically in the context of Integrated Coastal Zone Management plans. As there is no standardized method for cost evaluations in this field, it is suggested that clear guidelines should be produced on the basis of simplicity for use by end-users. The integration between historical databases of the physical parameters of storms and detailed cost evaluation information would support the development of a knowledge background in end-users and justify the development of adaptation strategies.  相似文献   
234.
The implementation of an adaptive cluster sampling design often becomes logistically challenging because variation in the final sampling effort introduces uncertainty in survey planning. To overcome this drawback, an inexpensive and easy to measure auxiliary variable could be used in a two-phase survey strategy, called adaptive cluster double sampling (Félix-Medina and Thompson in Biometrika 91:877–891, 2004). In this paper, a two-phase sampling strategy is proposed which combines the idea of adaptive cluster double sampling with the principle of post-stratification. In the first-phase an adaptive cluster sample is selected by means of an inexpensive auxiliary variable. Networks from the first phase sampling are then post-stratified according to their size. In the second-phase, the network structure is used to select a subsample of units by means of stratified random sampling. The proposed sampling strategy employs stratification without requiring an a priori delineation of the strata. Indeed, the strata sizes are estimated in the course of the two-phase sampling process. Therefore, it is suitable for situations where stratification is suspected to be efficient but strata cannot be easily delineated in advance. In this framework, a new type of estimator for the population mean which mimics the stratified sampling mean estimator and an estimator of the sampling variance are proposed. The results of a simulation study confirm, as expected, that the use of post-stratification leads to gain in precision for the estimator. The proposed sampling strategy is applied for targeting an epiphytic lichen community Lobarion pulmonariae in a forest area of the Northern Apennines (N-Italy), characterized by several species of conservation concern.  相似文献   
235.
Green public procurement (GPP) promises great potential for improving the environmental impact of many public organizations. However, the effects this instrument will have in the near future are unclear as there is little evidence on its exact level of engagement. This study thus aims to analyze the contents of tenders in terms of green criteria by specifically focusing on the building and construction sector. A total of 164 Italian public tenders were analyzed according to a protocol of analysis based on the GPP toolkit developed by the European Commission. Starting from a content analysis used in previous studies, a complete list of green criteria was developed in order to investigate their prevalence in the sample selected, with the aim of exploring their frequency, distribution and correlation. The results revealed a limited use of green criteria, which were mainly included as technical specifications and award criteria, thus shedding light on the difficulties that procurers are experiencing in the implementation of GPP practices. Several suggestions for policy makers and managers are identified for a better and faster implementation of green public procurement tools and methods.  相似文献   
236.
We respond to the paper of Kruse-Plass et al. (Environ Sci Eur 29:12, 2017), published in this journal, regarding the risk to non-target lepidopteran larvae exposed to pollen from one or more of three Bt maize events (MON810, Bt11 and 1507). We emphasise that what is important for environmental risk assessment is not the number of pollen grains per se, but the degree of exposure of a NT lepidopteran larva to Bt protein contained in maize pollen. The main text of this response deals with general issues which Kruse-Plass et al. have failed to understand; more detailed refutations of each of their claims are given in Additional file 1. Valid environmental risk assessment requires direct measurement of pollen on leaves at varying distances outside a source field(s); such measurements reflect the potential exposure experienced by an individual larva on a host plant. There are no new data in the Kruse-Plass et al. paper, or indeed any data directly quantifying pollen on actual host-plant leaves outside a maize field; only data gathered within or at the edge of maize crops were reported. Values quoted by Kruse-Plass et al. for deposition on host plants outside the field were estimates only. We reiterate the severe methodological criticisms made by EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016], which render this estimation procedure unreliable. Furthermore, criticisms of EFSA (EFSA J 2015(13):4127, 2015) and of EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016] made by Kruse-Plass et al. are shown in Additional file 1 to be without foundation. We therefore consider that there is no valid evidence presented by Kruse-Plass et al. to justify their conclusions.  相似文献   
237.
The present paper refers to the results of a research project on the polychlorinated dibenzyil-p-dioxin (PCDD) and polychlorinated dibenzofurans repartition in particulate and volatile phase in emissions from municipal solid waste incinerators. The distribution of such micropollutants between the different phases is analyzed in terms of absolute weights and in terms of 2, 3, 7, 8 TCDD Equivalents. This paper shows that more than half of the total content of PCDD/Fs emitted are adsorbed in the fly ash, with the remaining part in the volatile phase. Such repartition is inverted if the PCDD/Fs are expressed in terms of 2, 3, 7, 8 TCDD Equivalent.  相似文献   
238.
The aim of the study was to determine if an As-contaminated soil, stabilized using zerovalent iron (Fe0) and its combination with gypsum waste, coal fly ash, peat, or sewage sludge, could be used as a construction material at the top layer of the landfill cover. A reproduction of 2 m thick protection/vegetation layer of a landfill cover using a column setup was used to determine the ability of the amendments to reduce As solubility and stimulate soil functionality along the soil profile. Soil amendment with Fe0 was highly efficient in reducing As in soil porewater reaching 99 % reduction, but only at the soil surface. In the deeper soil layers (below 0.5 m), the Fe treatment had a reverse effect, As solubility increased dramatically exceeding that of the untreated soil or any other treatment by one to two orders of magnitude. A slight bioluminescence inhibition of Vibrio fischeri was detected in the Fe0 treatment. Soil amendment with iron and peat showed no toxicity to bacteria and was the most efficient in reducing dissolved As in soil porewater throughout the 2 m soil profile followed by iron and gypsum treatment, most likely resulting from a low soil density and a good air diffusion to the soil. The least suitable combination of soil amendments for As immobilization was a mixture of iron with coal fly ash. An increase in all measured enzyme activities was observed in all treatments, particularly those receiving organic matter. For As to be stable in soil, a combination of amendments that can keep the soil porous and ensure the air diffusion through the entire soil layer of the landfill cover is required.  相似文献   
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