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951.
Effects of Natural Disasters on Conservation Policies: The Case of the 2008 Wenchuan Earthquake,China 总被引:1,自引:0,他引:1
Conservation policies are increasing in response to human-induced ecosystem degradation, but little is known about their interplay
with natural disasters. Through an analysis of satellite imagery and field data we evaluated the impacts of a devastating
earthquake on forest recovery and avoided forest loss estimated to have been obtained by two of the largest conservation programs
in the world. Results show that more than 10% of the forests in Wenchuan County, Sichuan province, China were immediately
affected by the 2008 earthquake, offsetting some gains in forest cover observed since the enactment of the conservation programs.
But without the enactment of these conservation programs, the combined effects of human disturbance and earthquake-induced
landslides could have severely reduced the region’s forest cover. The continuation—and enhancement—of incentives for participation
in conservation programs will be important for reducing the environmental impacts of the combined effects of human disturbance
and natural hazards not only in the study area but also in many disaster-prone regions around the world. 相似文献
952.
Ammonium nitrate is one of the most widespread contaminants related with the viability of natural amphibian populations. In this study we have evaluated in terms of mortality and total length the effects that a previous sublethal pulse to ammonium nitrate generates in Epidalea calamita. Experiments were divided in two phases. In the first one, tadpoles were exposed to two different treatments, with and without a low ammonium nitrate concentration (22 mg NH4NO3 L−1). The second phase consisted in static toxicity experiments from both origin treatments with five different nominal concentrations (0, 22, 45, 90 and 180 mg NH4NO3 L−1). Results showed that tadpoles that had experienced a previous sublethal exposure showed a negative effect on survival (57% of reduction in the LC50 value) and total length, throughout an increase in their sensitivity. These results could help us to understand the situation of amphibian populations inhabiting aquatic ecosystems exposed to discontinuous and variable pulses of pollutants. 相似文献
953.
Lindahl P Maquet A Hult M Gasparro J Marissens G González de Orduña R 《Journal of environmental radioactivity》2011,102(2):163-169
The distribution of natural radionuclides was studied in winter wheat plants collected from three sites in Belgium during 2004-2007. Activity concentrations of 40K, 226Ra, 228Ra and 228Th in organically and conventionally grown wheat, and in the corresponding soil samples, were determined using ultra low-level gamma-ray spectrometry. The observed soil-to-wheat concentration ratios were calculated for the different parts of the wheat plant (root, stem and grain) in the two agricultural systems (organic and conventional). There were large variations in radionuclide activity concentrations between the sites and fields, but no significant difference between conventionally and organically grown wheat plants was observed. 相似文献
954.
Organochlorine concentrations in franciscana dolphins, Pontoporia blainvillei, from Brazilian waters
Lailson-Brito J Dorneles PR Azevedo-Silva CE Azevedo Ade F Vidal LG Marigo J Bertozzi C Zanelatto RC Bisi TL Malm O Torres JP 《Chemosphere》2011,84(7):882-887
Blubber samples were collected from ten franciscana dolphins either incidentally captured in fishing operations or stranded on São Paulo (SP) and Paraná (PR) states littoral, Southeastern and Southern Brazilian coast, respectively. Determination of PCB, DDT and HCB concentrations were performed by capillary gas chromatograph coupled to electron capture detector (ECD). ΣDDT, ΣPCB and HCB concentrations ranged from 264 ng g−1 to 5811 ng g−1 lipid, from 909 ng g−1 to 5849 ng g−1 lipid and from 10 ng g−1 to 61 ng g−1 lipid, respectively. Regarding DDTs, the distribution of the mean percentages decreased in the following order: p,p′-DDE > p,p′-DDD > p,p′-DDT. The ΣDDT/ΣPCB ratio varied between 0.27 and 0.42 in Northern and Central SP coast, while in Southern SP and PR coast the values were 1.6 and 1.9, respectively. Dissimilarities in ΣDDT/ΣPCB ratios point to different sources of organochlorine compounds to franciscana dolphins in the study area. Considering the endocrine disruptive action of organochlorine compounds, the concentrations found in franciscana dolphins from Brazilian waters may represent an additional obstacle to the conservation of this endangered cetacean species. 相似文献
955.
Marta Doval Miñarro Enrique González Ferradás Jonathan Barberá Rico Fernando Díaz Alonso Francisco J. Marzal Martínez Cristina Romero Trigueros 《Environmental science and pollution research international》2011,18(3):436-445
Introduction
The change in light intensity that takes place when an ambient air sample is drawn into the detection chamber of a chemiluminescence monitor generates changes in the concentrations of several species, such as NO2, NO and O3. Although this phenomenon has been known for several decades, there is still no commonly accepted approach on when or how to correct for it in NO2 and O3 readings. 相似文献956.
Josep Peñuelas Angela Ribas B.S. Gimeno Iolanda Filella 《Environmental monitoring and assessment》1999,56(2):221-224
Evaluation of visual symptoms of ozone damage was conducted in the network of bioindicator rural stations of Catalonia (NE Spain) every 14 days from May to October. Damage rates of ozone (and consequently, ozone biomonitoring capacity of bioindicators) were found to vary highly in time and space depending on the local environmental and meteorological conditions. Lower ozone damage to foliage was produced when meteorological conditions favour stomata resistance. Modulatory effects of meteorological conditions need to be considered in biomonitoring and when modeling plant ozone doses and damage. 相似文献
957.
Influence of vegetation on the removal of heavy metals and nutrients in a constructed wetland 总被引:1,自引:0,他引:1
A free water surface wetland was built to treat wastewater containing metals (Cr, Ni, Zn) and nutrients from a tool factory in Argentina. Water, sediment and macrophytes were sampled in the inlet and outlet area of the constructed wetland during three years. Three successive phases of vegetation dominance were developed and three different patterns of contaminant retention were observed. During the Eichhornia crassipes dominance, contaminants were retained in the macrophyte biomass; during the E. crassipes+Typha domingensis stage, contaminants were retained in the sediment and in the T. domingensis dominance stage, contaminants were retained in sediment and in the macrophyte biomass. Removal efficiency was not significantly different among the three vegetation stages, except for NH(4)(+) and i-P(diss). Because of its highest tolerance, T. domingensis is the best choice to treat wastewater of high pH and conductivity with heavy metals, a common result from many industrial processes. 相似文献
958.
Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced. 相似文献
959.
Different formats of imprinted polymers for determining organotin compounds in environmental samples 总被引:2,自引:0,他引:2
Organotin compounds and their degradation products enter the environment mainly as a result of their use as biocides and antifouling paints. Analysis of these compounds in environmental samples has to be very sensitive and selective so that their concentrations corresponding to the low environmental target values can also be detected. Generally, analysis of a complex matrix leads to high interferences during the different process steps; clean-up procedures are recommended to overcome this problem. For the past many years, solid phase extraction by employing imprinted materials has been extensively used for many organic substances that are used for pre-concentration and clean-up purposes with excellent results. Here, we present three different imprinted polymers prepared via bulk, precipitation, and emulsion polymerization methods that use similar compositions. The synthesized polymer particles were characterized morphologically by employing scanning electron microscopy and Brunauer-Emmett-Teller analysis. Binding properties were calculated using the Langmuir-Freundlich isotherm. Depending on the properties of the materials, different analytical applications for complex matrices are proposed. These applications are mainly used on tributyltin and its degradation products for environmental analysis. 相似文献
960.
Cíntia Melazo Dias Kristina Stenström Igor Luiz Bacelar Leão Roberto Ventura Santos Iêda Gomes Nícoli Göran Skog Peter Ekström Rosangela da Silveira Corrêa 《Journal of environmental radioactivity》2009
Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental 14C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3 M NaOH solution. The trapped CO2 was analyzed for 14C by using a single stage accelerator mass spectrometry (SSAMS). 相似文献