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1.
The industrialization of the Paraíba Valley, Brazil has been driven since the 1950s by an intense urbanization process, while municipalities located far from the valley's economic center stagnated. Despite the economic differences and unequal population distribution in the region, the municipalities share similar topographic characteristics with a predominance of hilly terrains. The depletion of the soils' productive capacity after numerous land use cycles without adequate management practices was a common cause of land use abandonment. This research analyzes land use/cover data, environmental policies, census-based data, and interviews with stakeholders, to understand the factors that account for a forest transition in the Paraíba Valley where gains in forest cover more than offset any remaining deforestation. Local conditions, such as topography, land use history, environmental policies, engagement of society in complying with legal regulations, commodity markets, and the action of enforcement agencies, represent dimensions which, combined, have boosted forest transitions. 相似文献
2.
Andressa Cristhy Buch Maria Elizabeth Fernandes Correia Daniel Cabral Teixeira Emmanoel Vieira Silva-Filho 《环境科学学报(英文版)》2015
The increasing levels of mercury (Hg) found in the atmosphere arising from anthropogenic sources, have been the object of great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the atmosphere. The major input of Hg to ecosystems is through atmospheric deposition (wet and dry), being transported in the atmosphere over large distances. The forest biomes are of strong importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transference to the soil through litter, playing an important role as sink of this element. Soil microarthropods are keys to understanding the soil ecosystem, and for such purpose were characterized by the soil fauna of two Units of Forest Conservation of the state of the Rio de Janeiro, inwhich one of the areas suffer quite interference from petrochemicals and industrial anthropogenic activities and other area almost exempts of these perturbations. The results showed that soil and litter of the Atlantic Forest in Brazil tend to stock high mercury concentrations, which could affect the abundance and richness of soil fauna, endangering its biodiversity and thereby the functioning of ecosystems. 相似文献
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Andressa Cristhy Buch Maria Elizabeth Fernandes Correi Daniel Cabral Teixeir Emmanoel Vieira Silva-Filho 《环境科学学报(英文版)》2015,27(6):217-227
The increasing levels of mercury (Hg) found in the atmosphere arising from anthropogenic sources, have been the object of great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the atmosphere. The major input of Hg to ecosystems is through atmospheric deposition (wet and dry), being transported in the atmosphere over large distances. The forest biomes are of strong importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transference to the soil through litter, playing an important role as sink of this element. Soil microarthropods are keys to understanding the soil ecosystem, and for such purpose were characterized by the soil fauna of two Units of Forest Conservation of the state of the Rio de Janeiro, inwhich one of the areas suffer quite interference from petrochemicals and industrial anthropogenic activities and other area almost exempts of these perturbations. The results showed that soil and litter of the Atlantic Forest in Brazil tend to stock high mercury concentrations, which could affect the abundance and richness of soil fauna, endangering its biodiversity and thereby the functioning of ecosystems. 相似文献
4.
Marcia Marques Monica Ferreira da Costa Maria Irles de O. Mayorga Patricia R.C.Pinheiro 《Ambio-人类环境杂志》2004,33(1):58-66
发展中国家中正面临经济发展挑战的那些人口密集的流域盆地和海岸带地区可能会在各种问题上受到中度或严重的环境影响.这些由巴西东北部至南部流向大西洋海岸的汇水盆地包括广阔的气候带和多种生态系统.盆地边界以内分布着大西洋雨林、大范围的半干旱热带旱生林(caatinga)、广阔的树木及灌木林地(cerrado)、巴西6670km 海岸线的一大部分及其海洋生态系统.在过去的几十年中,这些自然资源上的人类活动不断发展.海滨化已给沿海生境及生物群落造成了沉重的负担.caatinga和cerrado中的大部分原生植被遭到了破坏,仅存留了7%的大西洋原始雨林.河口、海湾和沿海泻湖也遭到了无法恢复的破坏.土地使用、筑坝和分水等活动已成为造成生境丧失和水生生态系统改变的主要原因.尽管巴西东北部地区的干旱和东南部及南部地区的富庶和工业化之间形成明显反差,但给上述两种地区的生境和生物群落造成的影响是同样严重的.阻止环境恶化的努力没有见到效果.为此建议,应该实行将重点集中在水生生态系统完整性的一些更加综合性的环境政策,而不是把重点单独地集中在自然资源上. 相似文献
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The bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), searches in mixed conifer and deciduous forests of northern Europe for suitable branches of its host, Scots pine (Pinus sylvestris). We tested whether odors from several diverse nonhost trees and plants common in the habitat (e.g., mountain ash, Sorbus aucuparia; oak, Quercus robur; alder buckthorn, Frangula alnus; blueberry, Vaccinium myrtillus; raspberry, Rubus idaeus; and grass, Deschampsia flexuosa) would reduce the attraction of the bark beetle to traps releasing its aggregation pheromone components in the field. Volatiles from the leaves or bark of each of these plants significantly reduced the attraction of the beetles to their pheromone. Odors collected from these nonhosts and analyzed by GC/MS contained monoterpenes, sesquiterpenes, and green-leaf alcohols, several of which (e.g., 1-octene-3-ol and -caryophyllene) reduced the attraction to pheromone in the field and elicited electroantennographic responses. In the laboratory, reproduction by the beetle was marginal in nonhost Norway spruce, Picea abies, and was absent in the other nonhost trees. Olfactory avoidance of unsuitable nonhosts may have evolved due to advantages in avoiding mistakes during host selection. 相似文献
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Marize Pereira Miagostovich Flávia Ramos Guimarães Carmen Baur Vieira Tulio Machado Fumian Nilson Porto da Gama Matias Victoria Jaqueline Mendes de Oliveira Anna Carolina de Oliveira Mendes Ana Maria Coimbra Gaspar José Paulo Gagliardi Leite 《Food and environmental virology》2014,6(2):110-115
The preservation of water resources is one of the goals of the designation of parks that act as natural reservoirs. In order to assess the impact of the presence of humans in an environmental preservation area bordering urban areas, the presence of four pathogenic enteric viruses [group A rotavirus (RV-A), norovirus (NoV), human adenoviruses (HAdV), and hepatitis A virus (HAV)], as well as the physico-chemical parameters, and Escherichia coli levels were assessed in riverine water samples. From June 2008 to May 2009, monthly monitoring was performed along the Engenho Novo River. RV-A, NoV, and HAdV were observed in 29 % (31/108) of the water samples, with concentrations of up to 103 genome copies/liter. The natural occurrence of infectious HAdV was demonstrated by Integrated Cell Culture-PCR (ICC-PCR). This study confirms the suitability of using the detection of fecal-oral transmitted viruses as a marker of human fecal contamination in water matrices and indicates the spread of pathogenic viruses occurring in an alleged area of environmental protection. 相似文献
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Hirokatsu Akagi Koichi Haraguchi Yoshihide Kinjo Olaf Malm Fernando J. P. Branches Jeans R. J. Guimaraes 《环境科学学报(英文版)》2000,(Z1)
IntroductionSincetheearly 1980’s,rapidincreasesingoldminingactivitiesusingmercuryamalgamationtechniqueinmanydevelopingcountrieshasbeenoneofthemainsourcesofmercurypollution ,particularlyintheAmazonandothertropicalregions(Malm ,1990 ;Ramel,1996;Ikingura,1996;Lacerda,… 相似文献
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Yuan Li Yanqun Zu Qixian Fang Zhaohua Gao Christian Schvartz 《Frontiers of Environmental Science & Engineering in China》2009,3(3):325-333
This paper studied the relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining
sites in Yunnan, China. 50 herbaceous plant samples of 9 plant species from 4 families and 50 soil samples were collected
and then ana1yzed for the tota1 concentrations of Pb, Cd, and Zn. The results showed that the average concentrations of Pb,
Cd, and Zn in soil samples were 3772.83, 168.81, and 5385.65 mg/kg, respectively. The average concentrations of Pb, Cd, and
Zn were 395.68, 28.14, and 1664.20 mg/kg in the shoots, and 924.12, 57.25, and 1778.75 mg/kg in the roots, respectively. Heterospecific
plants at the same site and conspecific plants at various sites had different average levels of Pb, Cd, and Zn, both in the
shoots and the roots. Enrichment coefficients of Pb, Cd, and Zn were greater than 1 in 2, 3, and 9 herbaceous plant samples,
respectively. Translocation factors of Pb, Cd, and Zn were greater than 1 in 10, 17, and 25 herbaceous plant samples, respectively.
In all 50 samples, the concentrations of Pb, Cd, and Zn between the shoots and the roots, the shoots, and the soils, and the
roots and the soils had significant positive relationships. 相似文献
9.
《Atmospheric Environment. Part A. General Topics》1991,25(10):2371-2383
Expressions are derived to readily compare contributions to overall mass transport limitation by gas-phase diffusion, interfacial transport and aqueous-phase diffusion to the overall rate of reaction in liquid droplets. The three criteria previously derived by Schwartz (1986, in Chemistry of Multiphase Atmospheric Systems, pp. 415–471, Springer) for the absence of mass transport limitation are shown to be special cases of the more general criterion obtained here. Sensitivity of the characteristic time to achieve steady state to the accommodation coefficient is examined. Inequalities are established that give lower and upper bounds of mass transport limitation in cases of non-first-order chemical kinetics. 相似文献
10.
Joseane Simone de Oliveira Pereira Lidiane Rodrigues da Silva Amanda de Meireles Nunes Silas de Souza Oliveira Eliane Veiga da Costa Edson Elias da Silva 《Food and environmental virology》2016,8(1):27-33
Wild polioviruses still remain endemic in three countries (Afghanistan, Pakistan, and Nigeria) and re-emergency of wild polio has been reported in previously polio-free countries. Environmental surveillance has been used as a supplementary tool in monitoring the circulation of wild poliovirus (PVs) and/or vaccine-derived PVs even in the absence of acute flaccid paralysis cases. This study aimed to monitor the presence of polioviruses in wastewater samples collected at one wastewater treatment plant located in the municipality of Rio de Janeiro, Brazil. From December 2011 to June 2012 and from September to December 2012, 31 samples were collected and processed. RD and L20B cell cultures were able to isolate PVs and non-polio enteroviruses in 27/31 samples. Polioviruses were isolated in eight samples (type 1 Sabin = 1, type 2 Sabin = 5, and type 3 Sabin = 2). Vaccine-derived polioviruses were not detected nor evidence of recombination with other PVs or non-polio enterovirus serotypes were observed among the isolates. The Sabin-related serotypes 2 and 3 presented nucleotide substitutions in positions associated with the neurovirulent phenotype at the 5′-UTR. Changes in important Amino acid residues at VP1 were also observed in the serotypes 2 and 3. Environmental surveillance has been used successfully in monitoring the circulation of PVs and non-polio enteroviruses and it is of crucial importance in the final stages of the WHO global polio eradication initiative. Our results show the continuous circulation of Sabin-like PVs and non-polio enteroviruses in the analyzed area during the study period. 相似文献
11.
2012年-2016年乐亭酸雨变化特征及影响因素分析研究 总被引:1,自引:0,他引:1
利用2012年-2016年乐亭国家基本气象站气象观测资料,分析了乐亭酸雨变化特征和降水量、风向、风速等气象因素对酸雨的影响.结果表明:年平均降水pH值和年酸雨频率呈下降趋势、平均K值呈上升趋势;秋季酸雨程度在四季中最严重,平均pH值为4.50,酸雨频率为38.4%;月平均pH值和酸雨频率呈现波动;酸雨平均pH值随降水量的增加而下降,酸雨频率随降水量的增加不断上升;月平均风速越大,月平均pH值越大,酸雨频率越小;酸雨发生时地面主导风向为NE、ENE、E,与上游地区燃煤型钢铁企业有一定关系. 相似文献
12.
通过对来宾市城区降水的主要金属元素K,Na,Ca,Mg浓度值测试分析,初步摸清来宾市城区降水中4种金属元素的浓度范围和污染状况. 相似文献
13.
Grace B. Villamor Febrina Desrianti Ratna Akiefnawati Sacha Amaruzaman Meine van Noordwijk 《Mitigation and Adaptation Strategies for Global Change》2014,19(6):733-755
This study explores the role of gender as a factor in decision making about alternative land use options and in responses to new investment opportunities, which has received little attention to date. An observational study to determine the different factors affecting male and female decisions to change land use at the individual level in a forest margin landscape in Jambi (Sumatra, Indonesia) was combined with a set of role playing games (RPGs) designed to assess participant responses in a simulated social setting of women-only and men-only groups. The RPG included simulated agents offering new opportunities to convert or conserve agroforest. In the study area, rubber (Hevea braziliensis) agroforests that support high biodiversity and carbon storage are giving way to monoculture rubber and oil palm (Elaeis guineensis) plantations. When women from both the upland and lowland villages played the RPGs, external investors proposing logging or oil palm conversion were approached very positively and the resulting land use change was more dynamic and extensive than in the equivalent men-only groups. Consequently, women outperformed men in achieving income targets. In lowland areas gender is strongly associated with land use change, while in the uplands the level of conservation awareness plays a more crucial role in the maintenance of rubber agroforests. Based on the data, and contrary to expectations and gender stereotypes, it is expected that the greater involvement of women in landscape level decision making will increase emissions from deforestation and forest degradation in the area, posing further challenges to efforts to reduce such emissions. 相似文献
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依据湖南省1993-2000年监测酸雨的数据资料,对湖南省酸雨的变化特征、分布及目前的状况和成因进行了分析.结果表明,湖南省降水pH值小于5.0的强酸性降水地区主要分布在湘中南和西南部,弱酸性降水区则分布在湘中地区;除怀化和洪江两地外,湖南降水阴阳离子基本平衡;湖南地区降雨为典型的硫酸型降雨,酸雨的形成主要受局地源的影响,其次是土壤、地形、气候和中远距离的输送等自然因素的作用.笔者认为能源结构和工业污染物等社会因素在酸雨的形成中具有决定性的作用. 相似文献
16.
Saiful Arif Abdullah 《环境科学学报(英文版)》2003,15(2):267-270
This paper presents the pattern and changes of fragmented forest in relation with changes of total forest cover in the state of Selangor in three decades.In this study,inventoried forest cover maps of Selangor in 1971/1972,1981/1982 and 1991/1992 produced by the Forestry Department of Peninsular Malaysia were digitized to examine the changes in area and number of fragmented forest.Results showed that in 1971/1972,16 fragmented forests were identified in Selangor.All fragmented forests were identified as diptercoarp forest.A decade later the number of fragmented forests increased by approximately 44%(23).Of the 23 fragmented forests,two were peat swamp forests whereas the remaining were dipterocarp forests.In 1991/1992 the number of fragmented forests(12)was reduced by 47.8%.Two of the fragmented forests were Fragmentation of both dipterocrp and peat swamp forests occurred profoundly during the period between 1971/1972and 1981/1982,which consequently increased the number of fragmented forests compared with before the period of 1971/1972 where fragmentation happened only at dipterocarp forests.However,many fragmented forests vanished between the 1981/1982 and 1991/1992 periods. 相似文献
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Chaowei Lai Zhen Ma Zaihua Liu Hailong Sun Qingchun Yu Fan Xia Xuejun He Qian Bao Yongqiang Han Xing Liu Haibo He 《环境科学学报(英文版)》2023,(9):68-83
The eutrophication of lakes is a global environmental problem. Regulating nitrogen(N) and phosphorus(P) on phytoplankton is considered to be the most important basis of lake eutrophication management. Therefore, the effects of dissolved inorganic carbon(DIC) on phytoplankton and its role in mitigating lake eutrophication have often been overlooked. In this study, the relationships between phytoplankton and DIC concentrations, carbon isotopic composition, nutrients(N and P), and hydrochemistry in... 相似文献
20.
绿色发展、循环发展、低碳发展是生态文明建设的重要途径和手段。本文阐述了绿色发展、循环发展、低碳发展的兴起及其在我国的发展。结合国情和发展阶段,分析了我国应如何认识和定位绿色发展、循环发展、低碳发展,并从理念先行、顶层设计和制度建设等方面提出了对策建议。 相似文献