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111.
Commodity distributions, the predominant relief response, are subject to growing criticism, while donors and humanitarian actors are increasingly viewing cash-based interventions as a viable alternative. This paper aims to contribute to the current debate on cash-based interventions by drawing on the experience of Action Contre la Faim in southern Somalia, where it has implemented cash for work programmes since 2004. The authors conclude that cash-based interventions are a feasible option in complex emergencies as well as in highly insecure environments as long as appropriate modalities are employed and objectives are clearly set in accordance with the needs and the context. Cash as a relief response offers wide-reaching possibilities for the future from both the perspective of the donor/agency and the standpoint of the beneficiary. It enables the beneficiaries to take control of the relief themselves and to adapt it to their individual requirements in a timely manner. 相似文献
112.
The rate and extent of deforestation determine the timing and magnitude of disturbance to both terrestrial and aquatic ecosystems. Rapid change can lead to transient impacts to hydrology and biogeochemistry, while complete and permanent conversion to other land uses can lead to chronic changes. A large population of watershed boundaries (N=4788) and a time series of Landsat TM imagery (1975-1999) in the southwestern Amazon Basin showed that even small watersheds (2.5-15 km2) were deforested relatively slowly over 7-21 years. Less than 1% of all small watersheds were more than 50% cleared in a single year, and clearing rates averaged 5.6%/yr during active clearing. A large proportion (26%) of the small watersheds had a cumulative deforestation extent of more than 75%. The cumulative deforestation extent was highly spatially autocorrelated up to a 100-150 km lag due to the geometry of the agricultural zone and road network, so watersheds as large as approximately 40000 km2 were more than 50% deforested by 1999. The rate of deforestation had minimal spatial autocorrelation beyond a lag of approximately 30 km, and the mean rate decreased rapidly with increasing area. Approximately 85% of the cleared area remained in pasture, so deforestation in watersheds of Rond?nia was a relatively slow, permanent, and complete transition to pasture, rather than a rapid, transient, and partial cutting with regrowth. Given the observed landcover transitions, the regional stream biogeochemical response is likely to resemble the chronic changes observed in streams draining established pastures, rather than a temporary pulse from slash-and-burn. 相似文献
113.
Pair bonds can end in two different ways: either death of the partner or divorce, where the frequency of divorce varies enormously
among bird species, from 0% to 100%. To better understand this variation, we created and analyzed the largest dataset so far,
consisting of 158 species and 20 variables that quantify the species’ body size, life history, diet, and other characteristics.
Our results suggest that species with a high divorce rate have a high mortality rate, tend to be ornamented and sexually dichromatic,
live colonially, and form part-time rather than continuous partnerships. Traits quantifying body size or life history are
often nonlinearly related with divorce rate. These nonlinearities might (partly) be caused by nonlinear relationships of the
same traits with mortality rate which is, in turn, linearly related with divorce rate. In contrast to what has been found
previously, mortality rate appears as a key factor for divorce rate in our study. This makes sense, as the likelihood that
a partner survives from one year to the next decreases with increasing mortality rate, diminishing the likely success of a
partner that attempts to locate its previous partner. We also found taxonomic differences in divorce rate. Specifically, Anseriformes
have an exceptionally low divorce rate, which, however, can be explained by the generally important determinants of divorce
rate: They also have a lower mortality rate, lower degree of ornamentation and coloniality, and more continuous partnerships
than members of other orders.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
114.
Pawlik-Skowrońska Barbara Toporowska Magdalena Mazur-Marzec Hanna 《Environmental science and pollution research international》2019,26(12):11793-11804
Environmental Science and Pollution Research - Cyanobacterial blooms in eutrophic water bodies are a worldwide problem. Combined effects of mixtures of secondary metabolites produced by different... 相似文献
115.
Coal-based power generates large quantities of coal ash in South Korea. However, coal ash recycling is still inactive and most wasted coal ash is buried in landfills. Recently, beneficial uses of coal ash such as in mine reclamation sites has been increasingly considered; however, as a result of legal limitations due to environmental concerns, the utilization of coal ash at mine reclamation sites has procrastinated. Consequently, to resolve this issue, the relevant environmental impact of coal ash must be considered. Therefore, a leaching assessment framework to assess the environmental impact of coal ash utilization at South Korean mine reclamation sites is presented. The framework was used to identify leaching mechanisms and support an assessment of the environmental impact of coal ash usage at mine reclamation sites in South Korea. This framework could provide guidance with regard to designing more realistic leaching procedures appropriate for all mine conditions and could support the development of regulations and protocols for future environment-friendly coal ash usage. 相似文献
116.
Meraj Alam Khan Ayaz Mahmood Dar Mohd Arsalan 《Journal of Polymers and the Environment》2017,25(3):717-727
A series of organic–inorganic conducting nano polymer-matrix composite cation-exchanger have been synthesized via sol–gel method and characterized through FTIR, XRD, TGA-DTA, SEM, and TEM studies. The structural studies confirm the semi-crystalline nature of the material but the morphology of the exchanger gets changed after incorporation of inorganic moiety. The particle size of the nano-composite was found to be 19.2 nm. The observed band gap for the different samples was found to be in the range of 3.70–4.61 eV which shows that nano-composite material covers semiconducting range but the resistivity of samples is highly dependent on the percentage of inorganic part in the composite. Further the oxidative degradation of the polymer backbone begins after the removal of trapped water successively followed by dopant and low molecular weight oligomers. During the antimicrobial screening, the nano-composite was found to be active against different strains of bacteria and fungi. Gel electrophoresis and molecular docking studies were carried out to check the interaction and mechanism of inhibition of microbial growth, respectively by studying the effect of the nano-composite with DNA-Topoisomerase-1. 相似文献
117.
Fujiwara F Dos Santos M Marrero J Polla G Gómez D Dawidowski L Smichowski P 《Journal of environmental monitoring : JEM》2006,8(9):913-922
A four-step chemical sequential extraction procedure was used to evaluate the distribution of Al, As, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn in airborne particulate matter collected on glass fibre filters using a high-volume sampler. Two sets of samples were collected in 2001 (winter and summer campaigns) in representative zones of an industrial city of Argentina. The leaching scheme was applied to PM-10 particles and consisted in extracting the elements in four fractions, namely soluble and exchangeable elements; carbonates, oxides and reducible elements; bound to organic matter and sulfidic metals; and residual elements. Metals and metalloids at microg g(-1) level were determined in each fraction by inductively coupled plasma optical emission spectrometry (ICP OES). Analyte concentration varied from 14 microg g(-1) (equivalent to 1.0 ng m(-3)) for As to 11.8 mg g(-1) (equivalent to 2,089 ng m(-3)) for Al. Seven elements, namely Al, Cr, Fe, Mn, Pb, Ti and Zn showed similar distributions in both seasons while As was distributed in a significantly different manner in each season. The results exhibited low As contents in the first and second fractions that could be associated with routine coal combustion and a high content in the third and fourth fractions of the summer samples that could be linked to the use of pesticides. Aluminium, As, Cu, Mn, Ni, Ti, V and Zn were found in different percentages in the more bioavailable aqueous fraction with As, Mn, V and Zn exhibiting solubilities greater than 1% while Cr and Pb being insoluble. The content of Al, Cr, Cu, Fe, Ni, Pb, and Zn in the residual fraction was, in average, higher than 50%. A comparative assessment of the use of the underlying information available from fractionation studies compared to that obtained from total element content was done for Fe and Mn. It showed that the results obtained using chemical sequential extraction procedures allowed further discrimination of the potential air pollution sources. 相似文献
118.
Tore Sderqvist Hanna Nathaniel Daniel Franzn Frida Franzn Linus Hasselstrm Fredrik Grndahl Rajib Sinha Johanna Stadmark sa Strand Ida Ingmansson Sofia Lingegrd Jean-Baptiste Thomas 《Ambio》2022,51(5):1302
Harvesting beach-cast can help mitigate marine eutrophication by closing land-marine nutrient loops and provide a blue biomass raw material for the bioeconomy. Cost–benefit analysis was applied to harvest activities during 2009–2018 on the island of Gotland in the Baltic Sea, highlighting benefits such as nutrient removal from the marine system and improved recreational opportunities as well as costs of using inputs necessary for harvest. The results indicate that the activities entailed a net gain to society, lending substance to continued funding for harvests on Gotland and assessments of upscaling of harvest activities to other areas in Sweden and elsewhere. The lessons learnt from the considerable harvest experience on Gotland should be utilized for developing concrete guidelines for carrying out sustainable harvest practice, paying due attention to local conditions but also to what can be generalized to a wider national and international context.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01641-8. 相似文献
119.
Mechanical and Thermal Properties of Bamboo Microfibril Reinforced Polyhydroxybutyrate Biocomposites
R. Krishnaprasad N. R. Veena Hanna J. Maria Rathish Rajan Mikael Skrifvars Kuruvilla Joseph 《Journal of Polymers and the Environment》2009,17(2):109-114
In the present investigation, microfibrils were extracted from raw bamboo and characterized using scanning electron microscope.
Composites based on polyhydroxybutyrate (PHB) and bamboo microfibril were prepared with various microfibril loading. The mechanical
and thermal properties of the resulting composites were measured. Tensile strength and impact strength of the composites were
found to be increasing with increase in the loading of bamboo microfibrils, reached an optimum and thereafter decreased with
further increase in microfibril loading. Percentage crystallinity was found to be increasing with increase in fibril loading.
Thermal stability of the composite was higher than that of pure PHB. The composite could be developed further for various
structural applications. 相似文献
120.
Wenyu Huang Marcello Brigante Feng Wu Khalil Hanna Gilles Mailhot 《Environmental science and pollution research international》2013,20(1):39-50
The main disadvantage of using iron mineral in Fenton-like reactions is that the decomposition rate of organic contaminants is slower than in classic Fenton reaction using ferrous ions at acidic pH. In order to overcome these drawbacks of the Fenton process, chelating agents have been used in the investigation of Fenton heterogeneous reaction with some Fe-bearing minerals. In this work, the effect of new iron complexing agent, ethylenediamine-N,N'-disuccinic acid (EDDS), on heterogeneous Fenton and photo-Fenton system using goethite as an iron source was tested at circumneutral pH. Batch experiments including adsorption of EDDS and bisphenol A (BPA) on goethite, H2O2 decomposition, dissolved iron measurement, and BPA degradation were conducted. The effects of pH, H2O2 concentration, EDDS concentration, and goethite dose were studied, and the production of hydroxyl radical (?OH) was detected. The addition of EDDS inhibited the heterogeneous Fenton degradation of BPA but also the formation of ?OH. The presence of EDDS decreases the reactivity of goethite toward H2O2 because EDDS adsorbs strongly onto the goethite surface and alters catalytic sites. However, the addition of EDDS can improve the heterogeneous photo-Fenton degradation of BPA through the propagation into homogeneous reaction and formation of photochemically efficient Fe-EDDS complex. The overall effect of EDDS is dependent on the H2O2 and EDDS concentrations and pH value. The high performance observed at pH 6.2 could be explained by the ability of O 2 ?? to generate Fe(II) species from Fe(III) reduction. Low concentrations of H2O2 (0.1 mM) and EDDS (0.1 mM) were required as optimal conditions for complete BPA removal. These findings regarding the capability of EDDS/goethite system to promote heterogeneous photo-Fenton oxidation have important practical implications for water treatment technologies. 相似文献