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91.
The need for quick identification of priority areas for biodiversity protection makes rapid assessment methods important management tools for defining conservation strategies. An increasingly used rapid assessment method is rapid ecological assessment (REA), a fast and flexible survey directed toward selected indicator species and vegetation forms. The purpose of this study was to propose and test REA based on plant community features of the semideciduous Atlantic forest (SAF). Correlation tests were performed between data collected by REA and plant species diversity, richness, and abundance collected by conventional woody plant inventory methods. The study was conducted in 21 SAF patches in Northern Paraná State, Brazil. The phytosociological inventory was conducted along a single transect and required 2 days to complete (excluding time spent for herbarium identification), whereas REA was conducted along three to four transects per working day. REA results correlated positively with woody plant diversity, proving REA to be an efficient method for defining the conservation status of SAF fragments, but accuracy of evaluations of threats to biological integrity are relatively low. Both the selection of appropriate variables and the skill level of field staff are critical and can strongly influence REA results.  相似文献   
92.
The genotoxicity potential of silver nanowires synthesized via the solution-based polyol method has been investigated. They were found to be non-mutagenic in three Salmonella strains and were not genotoxic in a clastogenicity assay in mice. Residual surfactant was found to have an effect on the toxicological properties of the nanowires by increasing the rate of Ag+ release. Residual surfactant can be easily degraded via a UV treatment.  相似文献   
93.
Environmental Science and Pollution Research - Settleable particulate matter (SPM), especially coarser particles with diameters greater than 10 μm, has been found culprit of high...  相似文献   
94.
Carrot (Daucus carota L.) is a vegetable crop that is grown throughout the year across various regions of Brazil in rotation or in succession to other cultures. Herbicide residual effect has emerged as a concern, because of the possibility of carryover. Thus, the objective of this study was to evaluate the effect of tembotrione and atrazine residues – in mixture and isolated – on carrot planted in succession to corn. The experiment was designed in randomized blocks with five replications. Treatments consisted of tembotrione (50.4 g ha?1), tembotrione (100.8 g ha?1), tembotrione + atrazine (50.4 g ha?1+ 2 L ha?1), tembotrione + atrazine (100.8 g ha?1+ 2 L ha?1), and atrazine (2.00 L ha?1) applied eight months before carrot seeding, plus a control treatment with no herbicide application. Investigated variables were shoot dry mass, productivity, and classification of carrot roots. The presence of atrazine and tembotrione decreased dry mass in the area, and only tembotrione reduced total root productivity. Thus, there is a carryover effect to tembotrione application that reduces the dry matter accumulation of shoot and total productivity, and an atrazine + tembotrione (100.8 g ha?1) mixture reduces the total productivity after application of these herbicides to soil.  相似文献   
95.
The aim of this paper was to describe a new energy dependency score methodology and its consequent application to cars sold in twelve regions: Europe (EU-28) and eleven specific countries worldwide (Australia, Brazil, China, India, Japan, Norway, Portugal, Russia, Saudi Arabia, South Africa and USA). This methodology was developed as a potential tool to inform consumers of their choice impact on the country’s economy. This methodology is based on primary energy assessments and origins for each energy pathway associated with a gasoline-, diesel-, natural gas (used for H2 production)- or electricity (balanced with country electricity mix)-powered vehicle. An energy dependency index was attributed to the best-case (100 % endogenous production) and worst-case (0 % endogenous production) scenarios and consequently weighted with vehicle fuel consumption. This enabled obtaining an energy dependency index (10–0). This index could be assigned to an environmental and social index to provide a sustainability index and therefore complement a road vehicle environmental rating system, providing a combined index rating. Internal combustion engine vehicles and hybrid vehicles (that have oil products as energy source) rate the lowest for almost all locations, with the exception of regions that are energy independent (Norway, Saudi Arabia or Russia). Electric vehicles rank higher when comparing to the other technologies analyzed for all locations in this study. The plug-in hybrid electric vehicle shows generally a rank in an intermediate place, except for Japan where it scores lower than all other technologies.  相似文献   
96.
The increasing awareness of environmental issues attracts more attention on environmentally friendly energy sources. This leads to increasing research on effective use of renewable energy sources. Among them, wave energy offers a high potential. The wave energy converter systems used for transforming the wave energy into electrical energy have been a main research topic for decades. However, only a few of these systems has been successfully implemented. There seems to be some technical problems one of which is on their control applications. It has been reported that by means of appropriate control implementation, the performance of the wave energy converter system could be improved considerably. In literature, many different control techniques are reported. They appear to be weak due to implementation related restrictions. The present study proposes a novel control technique that is far more practical based on quantization of control settings. Various quantization levels and their effect on system power capture performance are studied. The technique assumes use of realistic off-the-shelf components with realistic features. The proposed method utilizes time-series-analysis technique with online parameter estimation feature. This new method does not require any knowledge of previous or future states of any of the system or sea state parameters, but only the currently available and measurable ones. The approach of the new control technique sets it apart from most of the previously reported ones. Therefore, the proposed technique is not only very much practical but also very much useful in improvement of the system power performance relative to passive techniques.  相似文献   
97.
Significant knowledge gaps exist regarding the fate and transport of persistent organic pollutants like dichlorodiphenyltrichloroethane (DDT) in tropical environments. In Brazil, indoor residual spraying with DDT to combat malaria and leishmaniasis began in the 1950s and was banned in 1998. Nonetheless, high concentrations of DDT and its metabolites were recently detected in human breast milk in the community of Lake Puruzinho in the Brazilian Amazon. In this work, we couple analysis of soils and sediments from 2005 to 2014 at Puruzinho with a novel dynamic floodplain model to investigate the movement and distribution of DDT and its transformation products (dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) and implications for human exposure. The model results are in good agreement with the accumulation pattern observed in the measurements, in which DDT, DDE, and DDD (collectively, DDX) accumulate primarily in upland soils and sediments. However, a significant increase was observed in DDX concentrations in soil samples from 2005 to 2014, coupled with a decrease of DDT/DDE ratios, which do not agree with model results assuming a post-ban regime. These observations strongly suggest recent use. We used the model to investigate possible re-emissions after the ban through two scenarios: one assuming DDT use for IRS and the other assuming use against termites and leishmaniasis. Median DDX concentrations and p,p′-DDT/p,p′-DDE ratios from both of these scenarios agreed with measurements in soils, suggesting that the soil parameterization in our model was appropriate. Measured DDX concentrations in sediments were between the two re-emission scenarios. Therefore, both soil and sediment comparisons suggest re-emissions indeed occurred between 2005 and 2014, but additional measurements would be needed to better understand the actual re-emission patterns. Monte Carlo analysis revealed model predictions for sediments were very sensitive to highly uncertain parameters associated with DDT degradation and partitioning. With this model as a tool for understanding inter-media cycling, additional research to refine these parameters would improve our understanding of DDX fate and transport in tropical sediments.  相似文献   
98.
The forest–grassland mosaics of southern Brazil have been subject to many land use and policy changes over the decades. Like many grasslands around the world, the Campos grasslands are declining with few conservation efforts underway. In contrast, forests receive much attention and many incentives. It is hypothesized that perception of land cover has the potential to shape ecosystems. Here we conduct a questionnaire to further our understanding of decision-making practices that alter landscapes (Campos grassland, Araucaria forest, agriculture and plantation) and direct land policies in the region. Our analysis reveals that plantations are significantly less desirable than the other landscape types. However, plantation land use has increased by 87 % over the past few decades, as a result of industry and government incentives. The proportions of other landscape types have remained consistent over the past two decades. Restoration of native vegetation is not a priority of landowners and restoration would require a financial incentive.  相似文献   
99.
Forest management today has to meet a number of objectives. Planning of multi-functional forest road networks is one essential for meeting the aims of the sustainable forest concept. Road construction damages the natural environment unless it is carefully thought out. As forest engineers we have to consider the protection of nature when designing forest roads. With this aim in mind, a new network planning approach was developed for wood-harvesting. A geographical information system (GIS) was used to evaluate the data and planning process. The new forest road network plan for Catak Forest District constituted the addition of a new 16-road segment, total length 59.067 km, to the existing road network plan, for the purpose of wood-harvesting operations. Forest road density value was determined as 22.8 m/ha: the opening-up rate of the area was increased to 77.8% and the opening-up rate of the existing stand value was increased to 94.3% after close examination. 90.2% of roads were planned for the forest areas where there is likely to be minimal negative environmental impact.  相似文献   
100.
The Mondego River estuary demonstrates signs of pollution, but the levels of endocrine disrupting compounds (EDCs), such as the natural (17β-estradiol and estrone) and pharmaceutical (17α-ethynylestradiol) estrogens, xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono- and diethoxylates and bisphenol A), phytoestrogens (formononetin, biochanin A, daidzein, and genistein), and sitosterol were either poorly or never measured in this area. Thus, to conclude about the influx of EDCs in this estuary, water samples were taken every 2 months, during 1 year (2010) in low tide, at eight sites distributed along the estuary. Water samples (1 L) were preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by GC-MS. In summer, potentially hazardous amounts of estrogens (≈26 ng L?1), alkylphenols (≈11.5 μg L?1), alkylphenolethoxylates (≈13 μg L?1), and phytoestrogens (≈5.6 μg L?1) were measured. These data suggest that changes in the hydrodynamics of the estuary coupled with the increase of water temperatures interfere with the amount of EDCs in the water. Complementary physicochemical parameters also point to high levels of anthropogenic pollution in this area. Globally, the estrogenic load, expressed in ethynylestradiol equivalents, attained 71.8 ng L?1 demonstrating that, all together, the measured EDCs pose important health risks for both biota and humans.  相似文献   
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