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471.
In the Segara Anakan lagoon, Java, 21 tree species and 5 understorey genera have been identified. Average tree density is
0.80 ± 0.99 Ind./m2 with 48.71% seedlings and an average basal area of 9.86 ± 10.54 cm2/m2. Tree density and diversity are
high in the eastern part of the lagoon, located near the city of Cilacap. There, the dominant tree species are Aegiceras corniculatum, Nypa fruticans and Rhizophora apiculata, of which the two latter are characteristic for mature forests. By contrast, understorey species and the pioneer species (Avicennia alba,
Aegiceras corniculatum and Sonneratia caseolaris) dominate the central lagoon where several rivers discharge. Compared to former studies, seedling density and tree diameter
in the central lagoon has declined considerably and tree species dominance has changed. The high sedimentation rates and deforestation
are likely to prevent the formation of a mature forest there. Tree communities are more equilibrated in the eastern lagoon
which points to a more stable and less disturbed mangrove forest. 相似文献
472.
473.
I. Offenthaler R. Bassan G. Jakobi N. Kräuchi K.-W. Schramm P. Simon?i? P. Weiss 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3280-3289
PCDD/F and PCB concentrations in remote mountainous spruce stands of the Central European Alps show strong geographic variation. Independent of the matrix (0.5 year old needles, humus or mineral soil), the highest pollutant levels were always found at the lateral zones of the mountain range. High levels coincided with strong precipitation, particularly along the northern margin of the study region. The most volatile PCB congener propagated farther into the colder, drier central Alps than the heavier species. Matrices with different accumulation history (needles and humus) repeatedly reflected different spatial immission patterns. Consistent with its much longer exposure, pollutant levels in humus exceeded those of needles by up to two orders of magnitude. Needle contamination varied with altitude but the vertical trends were highly variable between transsects and changed between years, too. 相似文献
474.
Moses Makonjio Okello Simon K. Ole Seno Rita Wairimu Nthiga 《Natural resources forum》2009,33(2):123-133
Two of the eight Millennium Development Goals (MDGs) adopted by the United Nations General Assembly in September 2000 are: eradication of extreme poverty and hunger; and ensuring environmental sustainability. The link between depressed livelihoods and unsustainable use of land and natural resources can be seen in Kenyan rangelands. Here, the local community is dependent on land and its resources for livelihoods, but the demand and competition is increasing, endangering both the resources they depend on and threatening environmental health. Amboseli is an Arid and Semi-Arid Land (ASAL) area that experiences ecological constraints, resource limitations, and low economic investment. Local communities in such landscapes are resource-dependent for their daily livelihoods, and have few socio-economic opportunities. Pastoralism, which is the main source of their wealth, continues to decline and exploitation by a few local elites and poor local leadership further depresses livelihoods. Other challenges to these poor rural landscapes are increasing human population which increases demands on natural resources and environment; persistent hunger; low universal primary education; poor gender equality and empowerment of women; environmental degradation; and lack of local and global partnership for development. This paper focuses on the two Millennium Development Goals mentioned above. Linkages, challenges and opportunities in enhancing rural livelihoods while promoting environmental sustainability in rural landscapes of the Amboseli Rural Landscape are discussed. 相似文献
475.
Evidence abounds attesting to changes in the global climate. In Ghana, climate change and climate variability have brought several exposure-sensitivities on different people and at different times. Due to the multiplicity of climate change and climate variability effects, adaptation strategies invariably could be influenced by several factors. This paper assesses the adoption of adaptation strategies in the rural northern savannah zone of Ghana as a result of climate change and variability. Using two villages each from Savelugu Nanton, West Mamprusi and Kassena Nankana East Districts, which are slightly different as case studies, the paper unearthed panoply of varied adaptation strategies in each of them including intensification of irrigation; integration of livestock production; changes in tillage practices; fertiliser application on farms; shift from agriculture to non-farm jobs; seasonal migration and purchase of drought insurance for maize. The results indicate that the relativity in adoption and utilisation of the different adaptive strategies are interlinked with geographical, social, economic, institutional and political factors and processes in the villages. The findings drum home the essentiality of location-specific planned adaptation strategies for climate change through a bottom-up approach, in order to ensure their effectiveness and sustainability. 相似文献
476.
477.
This paper evaluates the feasibility of establishing a multiple-use marine protected area. The methodology was applied to evaluate three proposed sites in Chile with diverse conservation needs, social stress and poverty levels, and different economic activities (small-scale fishing, heavy industry, and mining activities). We use two broad categories for the evaluation: socio-economic and political–institutional. The methodology uses a combination of secondary data with personal interviews, workshops, and focus groups with stakeholders (e.g., fishermen, unions, politicians, social organizations) from different political, social, and economic backgrounds to characterize current and potential natural and social resources and to evaluate in an ordinal scale the feasibility of establishing the protected area. The methodology allows us to correctly identify the challenges faced in each site and can be used to develop appropriate strategies for balancing economic, social, and environmental objectives. This methodology can be replicated to evaluate the feasibility of other marine or terrestrial protected areas. 相似文献
478.
Guozhong Wu Cedric Kechavarzi Xingang Li Hong Sui Simon J.T. Pollard Frédéric Coulon 《Chemosphere》2013,90(8):2240-2246
A laboratory microcosm study was carried out to assess the influence of compost amendment on the degradation and bioavailability of PAHs in contaminated soils. Three soils, contaminated with diesel, coal ash and coal tar, respectively, were amended with two composts made from contrasting feedstock (green waste and predominantly meat waste) at two different rates (250 and 750 t ha?1) and incubated for 8 months. During this period the treatments were sampled for PAH analysis after 0, 3, 6 and 8 months. Total and bioavailable fractions were obtained by sequential ultrasonic solvent extraction and hydroxypropyl-β-cyclodextrin extraction, respectively, and PAHs were identified and quantified by GC–MS. Bioavailability decrease due to sorption was only observed at the first 3 months in the diesel spiked soil. After 8 months, compost addition resulted in over 90% loss of total PAHs irrespective of soil types. Desorption and degradation contributed to 30% and 70%, respectively, of the PAH loss in the spiked soil, while PAH loss in the other two soils resulted from 40% enhanced desorption and 60% enhanced degradation. Compost type and application rates had little influence on PAH bioavailability, but higher PAH removal was observed at higher initial concentration during the early stage of incubation. The bioavailable fraction of PAH was inversely correlated to the number of benzene rings and the octanol–water partition coefficient. Further degradation was not likely after 8-month although over 30% of the residual PAHs were bioavailable, which highlighted the application of bioavailability concept during remediation activities. 相似文献
479.
G. Simon Sylvestre 《Journal of environmental science and health. Part. B》2013,48(5):511-523
Abstract The results of the experiment reported in this paper demonstrate the influence of the soil sampling date on soil nitrifying activity, estimated in the laboratory. Treatment with propamocarb leads to parallel and reduced variations of this activity. 相似文献
480.
Dongli Wang Paramjit Behniwal Ruifang Fan Ho Sai Simon Ip Jianwen She 《Journal of environmental science and health. Part. B》2013,48(3):177-182
Urinary dialkyl phosphate metabolites (DAPs) are used as biomarkers to evaluate human exposure to organophosphate pesticides. The objective was to evaluate potential artifacts in urinary DAPs analysis during sample preparation and method calibration. Diluted urine pools were commonly used to prepare calibration standards to minimize the effects due to the complexity of urine matrix. Matrix effects on measurements of DAPs were evaluated by spiking known amount of standards into distilled water, synthetic urine and diluted urine pool. Different matrices resulted in similar concentrations detected for all target compounds, except dimethylphosphate (DMP) with the deviation of measurement as large as eight times the spiked amount. In this study, we also found that urinary particles, which usually appeared after thawing frozen human urine samples, could affect the measurements of DAPs, especially DMP and diethylthiophosphate (DETP). Results of DAPs measurements in three types of sample matrices, i.e. urine without particles, urine with particles and particles only were compared. DETP could be subject to large error during this preparation step. The use of deuterated and 13C12-labeled DAPs as internal standards is also evaluated. Overall, these issues can cause misidentification and inaccuracies, which may significantly affect the data quality. 相似文献