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91.
Obtaining quantitative information about the recovery of fire-affected ecosystems is of utmost importance from the management and decision-making point of view. Nowadays the concern about natural environment protection and recovery is much greater than in the past. However, the resources and tools available for its management are still not sufficient. Thus, attention and precision is needed when decisions must be taken. Quantitative estimates on how the vegetation is recovering after a fire can be of help for evaluating the necessity of human intervention on the fire-affected ecosystem, and their importance will grow as the problem of forest fires, climate change and desertification increases.This article performs a comparison of methods to extract quantitative estimates of vegetation cover regrowth with Landsat TM and ETM+ data in an area that burned during the summer of 1998 in the Liguria region (Italy). In order to eliminate possible sources of error, a thorough pre-processing was carried out, including a careful geometric correction (reaching RMSE lower than 0.3 pixels), a topographic correction by means of a constrained Minnaert model and a combination of absolute and relative atmospheric correction methods. Pseudo Invariant Features (PIF) were identified by implementing an automated selection method based in temporal Principal Component Analysis (PCA), which has been called multi-Temporal n-Dimensional Principal Component Analysis (mT-nD-PCA).Spectral Mixture Analysis (SMA) was compared against quantitative vegetation indices which are based on well known traditional vegetation indices like Normalized Difference Vegetation Index (NDVI) and Modified Soil Adjusted Vegetation Index (MSAVI). Accuracy assessment was performed by regressing vegetation cover results obtained with each method against field data gathered during the fieldwork campaign carried out in the study area. Results obtained showed how vegetation cover fractions extracted from the NDVI based quantitative index were the most accurate, being superior to the rest of the techniques applied, including SMA.  相似文献   
92.
Journal of Material Cycles and Waste Management - Predicting municipal solid waste (MSW) generation is fundamental in choosing and scaling the processes involved in municipal management. The...  相似文献   
93.
Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade‐offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat‐based approach to estimate the spatial distribution of opportunity cost to fishers in data‐poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no‐take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade‐offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation.  相似文献   
94.
This study addresses the means local administrators and legislators in emerging economies dispose of to implement directives passed down to them by international environmental agreements. Specific reference is made to agreements and policies dealing with fresh water supply and waste management. Although the Johannesburg Summit asked that the proportion of people without access to drinking water and basic sanitation be halved by 2015, actions need to be developed on a local scale to reach the target. They need to consider the existence of supply limits for water and the subtle difference between sanitation and waste collection. The concepts of reactive and proactive legislation are confronted. Proactive legislation, already used in the industrialized World, is proposed to introduce new patterns of behavior into emerging economy communities. The proposed legal texts have the capacity to be self-fulfilling in the quest for local compliance with international targets.  相似文献   
95.
96.
Activity profiles of excess 210Pb determined in three sediment cores from Amazon River mouth, Macapá city, Brazil, provided the evaluation of sedimentation rates, contributing to a better knowledge of the hydrological conditions in the site that is the capital of Amapá State and is drained by the waters of the huge Amazon River. Chemical data were also determined in the sediments, allowing identify signatures coupled to anthropogenic inputs held in the past in Amapá State. Significant direct relationships between LOI (loss on ignition) and organic matter were found for all sediments profiles. Silica was found to be inversely related to organic matter in the three profiles; its decrease accompanied an increase on the specific surface of the sediments. This relationship was confirmed by a great number of inverse significant correlations among silica and oxides Na2O, K2O, CaO, MgO, Al2O3, P2O5, Fe2O3 and MnO. It was possible to identify the role of organic matter on adsorption of several oxides in the core sediments profiles. Apparent sediment mass accumulation rates corresponding to values between 450 and 2510 mg cm−2 yr−1 were obtained, and are compatible with the results of others studies. The 210Pb activities in one sampling point suggested the occurrence of anthropogenic inputs related to the initial period of the mining activities conducted in Serra do Navio, Amapá State, for the commercialization of Mn ores. This was reinforced by the abrupt fluctuations in chemical data obtained for the sediments and composition of the interstitial waters occurring there. The Atlantic hurricane activity also appeared to affect the sedimentation rates in the area, as two different values were recorded in each profile.  相似文献   
97.
Hydrodynamic cavitation (HC)-based treatments have been proposed for the degradation of phenol as a toxic pollutant. The present work aimed to optimize the degradation of phenol using HC by means of Doehlert experimental design, which has not been previously addressed. Initially, operational parameters of hydraulic characteristics of the pump, inlet pressure, solution pH, and initial concentration were optimized; later, the effects of pH solution and H2O2 loading or initial pollutant concentration on phenol degradation were explored using the Doehlert experimental design. It was observed that phenol degradation is strongly dependent on the pH of the solution. Also, the acidic condition favors the formation of hydroxyl radicals and thus, the degradation of phenol. Based on the Doehlert matrix, the 94.1% phenol degradation and 68.60% total organic carbon (TOC) were obtained in 180 min at 304.5 mg/L of hydrogen peroxide at an initial concentration of 20 mg/L, 2.0 pH, and 90 psi inlet pressure, providing a cavitational yield of 6.33 × 10−6 mg/J and minimum treatment cost of US$/L 0.13. Overall, it has been observed that HC can be a promising route for the removal of pollutants (phenol) effectively using hydrogen peroxide as an additive.  相似文献   
98.
Environmental Science and Pollution Research - Bisphenol A (BPA) is a high production volume chemical that has wide industrial applications, especially as a color developer in thermal papers. The...  相似文献   
99.
The solid waste accumulation patterns on Tamandaré beach, Pernambuco State (Brazil), was assessed from February 2001 to July 2002. This beach is easily accessible, frequently used, and there is a public cleaning service. The beach is under the influence of three small coastal drainage basins. The study visually divided the beach into 15 segments according to the level of solid waste contamination into absent (A), trace (B), unacceptable (C) and objectionable (D). The lowest levels of contamination were found at the middle part of the study area, the most vulnerable in respect to coastal erosion presenting numerous interventions on the beach, absence of native vegetation and lesser width. The highest levels of contamination were at the northern and southern ends of the area, where there are no developments, the beach morphology favours deposition of sediments, there is native vegetation and the beach is wider. The D level did not occur within the area.  相似文献   
100.
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