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131.
Given the excessive use pressure on forests, characterisation of the major users of forest resources can help guide conservation efforts. This study examines whether socio-economic variables explain domestic wood use in an area of Atlantic forest in the community of Três Ladeiras (Pernambuco, north-east Brazil). Socio-economic data were collected from 62 households, and geometric measurements of wood products in each household were taken to calculate the wood volume. An informant in each household indicated the average replacement time for each type of wood use. Data were analysed for static volume (wood volume found at the time of the visit) and dynamic volume (rate of wood consumption, calculated as the ratio between volume and replacement time). Multiple regression analyses were performed to determine the relationships between wood volume (static and dynamic) and the number of species used; independent variables including monthly family income, number of residents, average age of heads of the household, age of oldest household member, average residence time of heads of the household, average education level of heads of the household and education level of the most educated household member. Monthly income was inversely related to the static wood volume (adjusted R 2 = 17.6%, p < 0.001), rate of wood consumption (adjusted R 2 = 23.0%, p < 0.001) and number of species used (adjusted R 2 = 22.3%, p < 0.001) and was the most important predictive variable for these three outcomes. Other factors such as average education level and average age of heads of the household were also explanatory variables of the total rate of wood consumption, as these two variables, together with monthly family income, explain 31.3% of the total dynamic volume. Given the high importance of income in our study, we suggest that future conservation strategies give special attention to the poorest members of the community.  相似文献   
132.
Environmental and Ecological Statistics - This paper presents an extension of the Geostatistical model under preferential sampling in order to accommodate possible local repulsion effects. This...  相似文献   
133.
Understanding the climate and its variability, in particular with regard to their socioeconomic impact, requires specific measurements of precipitation and temperature and their circulations. This becomes more important in applications to diverse systems. In order to improve knowledge about temporal changes and trends in temperature, we analyzed series of maximum and minimum daily surface temperatures at eight reference stations in southeastern South America during variable periods, with the longest periods of around 100 years. To study the evolution of the temperature series and to reduce the number of parameters, a nonhierarchical cluster analysis was performed. The algorithm assigns each day to one of four groups: warm, wet, cold and dry. Low frequency variations were found in these groups and their association with circulation structure, circulation patterns and precipitation. We concluded that the set of wet days is one of the main factors driving secular variations of maximum and minimum temperature and variations in precipitation. We also inferred that after 1920 till 1930, a low frequency oscillation is observed in the form of linear trends (increase of warm days and decrease of cold days).  相似文献   
134.
This work addresses increasing concerns about water management for rural productive activities in the vast dry regions of Latin America by assessing renewable energy technologies (RETs) that could be suitable for localized needs. Forecasted trends in climate change and variability make this analysis very relevant, in an area where very little published work exists. While Argentina is widely known for its fertile pampas, around 75 % of the country consists of dry lands. In addition, erosion is increasing by up to 650,000 hectares each year. The coordinated adoption of a set of actions, including land use planning and strengthening productive activities that guarantee access to water and improve water and soil management is needed. Renewable energies could help towards achieving these aims, if water is made available at affordable costs and with suitable technologies. This paper evaluates experiences with three RETs—photovoltaic pumping from deep wells, small wind turbine pumping, and high-power wind turbines, and discusses a potential role for use in rural Argentina. Although cheaper and more reliable renewable alternatives to energy sources such as diesel could be used for pumping from groundwater resources in isolated locations, limitations arise when pumping head and/or water volume requirements are large or highly seasonal. The cost increases and technical challenges of accessing this deeper water, as indicated by case studies, emphasize the importance of planning and support schemes development.  相似文献   
135.
Journal of Polymers and the Environment - This study was developed a novel nanostructured membrane by electrospinning process, from polyacrylonitrile (PAN) modify by hydroxypropyl methylcellulose...  相似文献   
136.
Environment Systems and Decisions - In this paper, we analyzed the association among trends in COVID-19 cases, climate, air quality, and mobility changes during the first and second waves of the...  相似文献   
137.
Environmental Science and Pollution Research - Wastewater tertiary treatment has been pointed out as an effective alternative for reducing the concentration of antibiotic resistant bacteria and...  相似文献   
138.
The aim of this study was to develop an objective method to determine the incidence of pleiomorphisms and its influence on the distribution of sperm morphometric subpopulations in ejaculates of howling monkeys (Alouatta caraya) by using a combination of computerized analysis system (ASMA) and principal component analysis (PCA) methods. Ejaculates were collected by electroejaculation methods on a regular basis from five individuals maintained under identical captive environmental, nutritional, and management conditions. Each sperm head was measured for dimensional parameters (Area [A, (square micrometers)], Perimeter [P, (micrometers)], Length [L, (micrometers)], and Width [W, (micrometers)]) and shape-derived parameters (Ellipticity [(L/W)], Elongation [(L???W)/(L?+?W)], and Rugosity [(4лA/P 2)]). PCA revealed two principal components explaining more than the 96 % of the variance. Clustering methods and discriminant analyzes were performed and seven separate subpopulations were identified. There were differences (P?<?0.001) in the distribution of the seven subpopulations as well as in the incidence of abnormal pleiomorphisms (58.6 %, 49.8 %, 35.1 %, 66.4 %, and 55.1 %, P?<?0.05) among the five donors tested. Our results indicated that differences among individuals related to the incidence of pleiomorphisms, and sperm subpopulational structure was not related to the captivity conditions or the sperm collection method, since all individuals were studied under identical conditions. In conclusion, the combination of ASMA and PCA is a useful clinical diagnostic resource for detecting deficiencies in sperm morphology and sperm subpopulations in A. caraya ejaculates that could be used in ex situ conservation programs of threatened species in Alouatta genus or even other endangered neotropical primate species.  相似文献   
139.
140.
Assessment of carcinogenic heavy metal levels in Brazilian cigarettes   总被引:1,自引:0,他引:1  
Total mercury (Hg(T)) and bioavailability Hg (Hg(HCl)) concentrations in soil were determined in five districts in Wuhu urban area. Spatial pattern of soil Hg concentration was generated through kriging technology. Results showed that Hg concentration in soil ranged from 0.024 to 2.844 mg kg(?-1) with an average of 0.207 mg kg(?-1). Hg concentration in soil appeared to have a block distribution and decreased from downtown to surrounding district. And Hg concentrations appeared to have a medium scale spatial auto correlation, strongly affected by human activity. The maximal Hg average concentration (0.332 mg kg(?-1)) in soil appeared in Jinghu district, where the high intensity of human activities is. Second highest Hg average concentration (0.263 mg kg(?-1)) in soil appeared in development district, where the intensive industrial activities are. Bioavailability Hg concentration in soil ranged from 2.6 to 4.9 μg kg(?-1) with an average of 3.8 μg kg(?-1), which had a ratio of 0.28~6.44% to total Hg. The ratios of bioavailability Hg to total Hg in vegetable soil were bigger than those of park soil. Correlation analysis showed that total Hg, organic matter, total phosphorus, and bioavailability Hg concentrations in soil were significantly positively correlated. Hg concentration in vegetable ranged from 2.7 to 15.2 μg kg(?-1) with an average of 6.5 μg kg(?-1). Hg concentration in vegetable was positively correlated with Hg(HCl) concentration in soil. According to the calculation on hazard quotient (HQ) for children, inhalation of Hg vapor from soil is the main exposure pathway, in which HQ is 2.517 × 10(?-2), accounting for 80.3% of the four exposure pathways. Hazard index (HI) of the four exposure pathways is lower than the "safe" level of HI = 1; therefore, exposure of soil Hg exhibited little potential health risk to children in Wuhu urban area.  相似文献   
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