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101.
We examined the long-term effects of a single application of potassium (K) fertilizer (100 kg K ha−1) in 1992 on 137Cs uptake in a forest ecosystem in central Sweden. 137Cs activity concentrations were determined in three low-growing perennial shrubs, heather (Calluna vulgaris), lingonberry (Vaccinium vitis-idaea) and bilberry (Vaccinium myrtillus), and in four wild fungal species (Cortinarius semisanguineus, Lactarius rufus, Rozites caperata and Suillus variegatus). Uptake of 137Cs by plants and fungi growing on K-fertilized plots 17 years after application of the K fertilizer was significantly lower than in corresponding species growing in a non-fertilized control area. The 137Cs activity concentration was 21-58% lower in fungal sporocarps and 40-61% lower in plants in the K-fertilized area compared with the control. Over the study period, this decrease in 137Cs activity concentration was more consistent in plants than in fungi, although the effect was statistically significant and strongly pronounced in all species. The effect of K fertilization in reducing 137Cs activity concentration in fungi and plants decreased over time but was still significant in 2009, 17 years after fertilization. This suggests that application of K fertilizer to forests is an appropriate and effective long-term measure to decrease radiocaesium accumulation in plants and fungi.  相似文献   
102.
103.
Spatial and temporal variations of sediment quality in Matanzas Bay (Cuba) were studied by determining a total of 12 variables (Zn, Cu, Pb, As, Ni, Co, Al, Fe, Mn, V, CO3 2?, and total hydrocarbons (THC). Surface sediments were collected, annually, at eight stations during 2005–2008. Multivariate statistical techniques, such as principal component (PCA), cluster (CA), and lineal discriminant (LDA) analyses were applied for identification of the most significant variables influencing the environmental quality of sediments. Heavy metals (Zn, Cu, Pb, V, and As) and THC were the most significant species contributing to sediment quality variations during the sampling period. Concentrations of V and As were determined in sediments of this ecosystem for the first time. The variation of sediment environmental quality with the sampling period and the differentiation of samples in three groups along the bay were obtained. The usefulness of the multivariate statistical techniques employed for the environmental interpretation of a limited dataset was confirmed.  相似文献   
104.
Photocatalytic degradation of bisphenol A (BPA) in waters and wastewaters in the presence of titanium dioxide (TiO2) was performed under different conditions. Suspensions of the TiO2 were used to compare the degradation efficiency of BPA (20 mg L?1) in batch and compound parabolic collector (CPC) reactors. A TiO2 catalyst supported on glass spheres was prepared (sol–gel method) and used in a CPC solar pilot plant for the photodegradation of BPA (100 μg L?1). The influence of OH·, O2 ·?, and h + on the BPA degradation were evaluated. The radicals OH· and O2 ·? were proved to be the main species involved on BPA photodegradation. Total organic carbon (TOC) and carboxylic acids were determined to evaluate the BPA mineralization during the photodegradation process. Some toxicological effects of BPA and its photoproducts on Eisenia andrei earthworms were evaluated. The results show that the optimal concentration of suspended TiO2 to degrade BPA in batch or CPC reactors was 0.1 g L?1. According to biological tests, the BPA LC50 in 24 h for E. andrei was of 1.7?×?10?2 mg cm?2. The photocatalytic degradation of BPA mediated by TiO2 supported on glass spheres suffered strong influence of the water matrix. On real municipal wastewater treatment plant (MWWTP) secondary effluent, 30 % of BPA remains in solution; nevertheless, the method has the enormous advantage since it eliminates the need of catalyst removal step, reducing the cost of treatment.  相似文献   
105.
The Convention on Biological Diversity is defining the goals that will frame future global biodiversity policy in a context of rapid biodiversity decline and under pressure to make transformative change. Drawing on the work of Indigenous and non-Indigenous scholars, we argue that transformative change requires the foregrounding of Indigenous peoples’ and local communities’ rights and agency in biodiversity policy. We support this argument with four key points. First, Indigenous peoples and local communities hold knowledge essential for setting realistic and effective biodiversity targets that simultaneously improve local livelihoods. Second, Indigenous peoples’ conceptualizations of nature sustain and manifest CBD’s 2050 vision of “Living in harmony with nature.” Third, Indigenous peoples’ and local communities’ participation in biodiversity policy contributes to the recognition of human and Indigenous peoples’ rights. And fourth, engagement in biodiversity policy is essential for Indigenous peoples and local communities to be able to exercise their recognized rights to territories and resources.  相似文献   
106.
This paper discusses international aid issues related to energy supply and sustainable development in the Pacific Islands. Certain foreign donors have focused their aid to the region mainly on poverty alleviation, and have failed to support critical sectors, such as the energy sector, which is one of the main driving forces in socio-economic development. As an example, this paper analyses the international aid program of Australia for renewable energy in the Pacific Island region. It is recommended that, in future, foreign aid take up the challenge of promoting recipient countries' capabilities in sustainable development. A key strategy to be adopted by foreign aid should be strengthening recipients' energy sectors, particularly renewable energy systems. It is argued that this approach will assist the long-term socio-economic development and environmental management of the region.  相似文献   
107.
Objective: According to the World Health Organization, the global burden of road traffic mortality exceeds 1.27 million people annually; over 90 percent occur in low- and middle-income countries. Brazil's road traffic mortality rate of ~20 per 100,000 is significantly higher than nearby Chile or Argentina. To date, there has been very little information published on road traffic fatalities among vulnerable road users (VRUs) in Brazil. Methods: Road traffic fatality data from 2000 to 2008 were extracted from Brazil's Mortality Information System (SIM). Road traffic deaths were extracted using the International Classification of Diseases (ICD-10) V-codes (V01-V89) and then subcategorized by VRU categories. Information was then disaggregated by gender, age, and region. Results: In 2008, 39,211 deaths due to road traffic injuries were recorded in Brazil, resulting in a crude mortality rate of 20.7 per 100,000 inhabitants. Pedestrian mortality averaged 5.46 deaths per 100,000 between 2000 and 2008. The mortality rate for elderly pedestrians (80+ years) is 20.1 per 100,000, over 10 times that of 0- to 9-year-olds. In the past decade, motorcycle occupant mortality has dramatically increased by over 300 percent from 1.5 per 100,000 in 2000 to 4.7 per 100,000 in 2008. The 20- to 29-year age group remains most affected by motorcycle deaths, with a peak fatality rate of 10.76 per 100,000 in 2008. The north and northeast regions, with the lower per capita gross domestic product (GDP), have higher proportions of VRU deaths compared with other regions. Conclusions: Vulnerable road users are contributing an increasing proportion of the road traffic fatalities in Brazil. Nationally, elderly pedestrians are at particularly high risk and motorcycle fatalities are increasing at a rapid rate. Less prosperous regions have higher proportions of VRU deaths. Understanding the epidemiology of road traffic mortality in vulnerable road user categories will better allow for targeted interventions to reduce these preventable deaths.  相似文献   
108.
The aim of this work was to study possible binding of 137Cs to various organic components in the soil and fungi, by using various sequential extraction procedures. The retention and binding of 137Cs has been studied in two horizons Of/Oh and Ah/B of a Ukrainian forest soil. The exchangeable fractions 137Cs from soil (sum of H2O and 1 M NH4OAc fraction) were found to be 12% in the organic-rich layer (range 11-14%) and 23% in the organic-poor (range 20-29%). The hydrolysis with 10% H2SO4 resulted in an additional release of 30% of 137Cs from the organic-rich soil (range 30-35%) and 38% from the organic-poor soil horizon (range 27-53%). Extraction with 30% H2O2 released 11 and 15% of the 137Cs activity from organic-rich and organic-poor soil horizons. The corresponding values for treatment with 98.8% NaOCl were about 27% in both types of soil. About 11% of the total 137Cs activity was found in the humic acid fraction, about 5% in the fulvic fraction and 46% in the residue fraction. Relatively high level of 137Cs activity in soil (ca. 50%) was thus still left unsolved in the residue fraction. About 29% of 137Cs activity concentration in fungal mycelia was found as water soluble with a range of 11 to 41%. Additionally 24% of the 137Cs activity from mycelia was released by 1 M ammonium acetate extraction. Together, water and 1 M ammonium acetate extraction released about 53% of the total 137Cs activity in the mycelia. In fruit bodies of mycorrhizal fungi, 68% of the total 137Cs inventory was found to be water soluble at room temperature and 93% at 80 degrees C.  相似文献   
109.
Experiments have been carried out on cultures of native algae of Andalucía (Spain) with effluents from the biological treatment of urban wastewaters by anaerobiosis, using continuous and discontinuous systems.The influence of different hydraulic retention times of the wastewater on the algal cultures has been determined: on the level of algal biomass reached, and on the degree of purification achieved, measured from the evolution of various quality parameters.  相似文献   
110.
Caprella scaura (Templeton in Trans Entomol Soc Lond 1:185–198, 1836) is a native species to the western Indian Ocean. It was first described from Mauritius and later reported from several regions of the world. During the last decade, the species spread out of the Adriatic Sea, and in 2005, C. scaura was reported in Gerona, on the north-eastern coast of Spain. The present study shows the recent rapid expansion of the species to the East Atlantic. During a sampling survey of harbours along the Strait of Gibraltar (Dec 2009–June 2010), we found high densities of C. scaura associated with the bryozoans Zoobotryon verticillatum Della Chiaje, 1822, in Chipiona and Bugula neritina (L.) in Cádiz, Atlantic coast of southern Spain; on the other hand, during May 2009, an important population of C. scaura was also found in the Canary Islands (Tenerife) associated with aquaculture resources. A total of 1,034 individuals of C. scaura were studied, and we confirm that the populations are effectively established, with high densities and reproducing females during the whole year. The population from Cádiz was characterised by smaller specimens but a higher number of eggs per female. These differences could be related to environmental conditions, mainly sea water temperature and to other factors such as competition with other species, or availability of food or substrate. Significant correlation was found between female size and number of eggs in the three populations, but egg size did not vary with female body length. The morphometric relation length/width of the second gnathopod was also calculated and compared between sexes: larger males presented longer gnathopods at the three sites. The most probable introduction vector of this species is shipping; in fact, the Strait of Gibraltar is characterised by an intense shipping traffic. Also, we have observed that the native Caprella equilibra Say, 1818, is being displaced by C. scaura in the harbour of Cádiz, where this species reach densities of 35,945 ind/1,000 g of B. neritina. Further experimental studies are necessary to explore the potential danger of this species, which might spread into natural habitats too.  相似文献   
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