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1.
The evolution of sustainability   总被引:1,自引:0,他引:1  
Six separate but related strains of thought have emerged prominently since 1950 in discussions of such phenomena as the interrelationships among rates of population growth, resource use, and pressure on the environment. They are the ecological/carrying capacity root, the resources/environment root, the biosphere root, the critique of technology root, the no growth/slow growth root, and the ecodevelopment root.Each of these strains of thought was fully developed before the word sustainable itself was used. Many of the roots are based on fundamentally opposing assessments of the future of mankind. Many of the roots, such as the ecology/carrying capacity root, are based on physical concepts, and they exclude normative values. Others, such as the ecodevelopment root, include such values as equity, broad participation in governance, and decentralized government.When the word sustainability was first used in 1972 in the context of man's future, in a British book,Blueprint for Survival, normative concepts were prominent. This continued to be the case when the word was first used in 1974 in the United States to justify a no growth economy.Sustainability was first used in a United Nations document in 1978. Normative concepts, encapsulated in the term ecodevelopment, were prominent in the United Nations publications.After about 1978, the term sustainability began to be used not only in technological articles and reports but also in policy documents culminating in the use of the term in the report of the summit meeting of the Group of Seven in 1989.The roots of the term sustainability are so deeply embedded in fundamentally different concepts, each of which has valid claims to validity, that a search for a single definition seems futile. The existence of multiple meaning is tolerable if each analyst describes clearly what he means by sustainability.  相似文献   
2.
西印度洋(WIO)地区以其迷人的海岸带、丰富的海洋生物多样性以及富饶的海洋和海岸带资源而著称.但是地处WIO地区的许多国家像肯尼亚、莫桑比克、索马里、南非、坦桑尼亚、科摩罗、马达加斯加、毛里求斯、留尼旺、塞舌尔等却极度贫困,特别是近二三十年以来,该地区的环境退化现象以及自然资源和生物多样性的下降越来越明显.  相似文献   
3.
This paper is part of a two-year study to investigate the feasibility of initiating a Clean Development Mechanism (CDM) project in an indigenous community of Eastern Panamá, Ipetí-Emberá. We use participatory mapping and matrices as well as household surveys to develop a land-use/land-cover baseline scenario and examine the role of local participation in assessing land-use change. In Ipetí, land-use change has not occurred in a linear way over the last decades, and our data unveils socio-economic factors as potential key drivers of change. The concordance that we observed between geographic information and individual and collective perceptions of land-use change substantiates the possibility of using local knowledge in the establishment of baseline data for CDM projects. Our calculations suggest that the total carbon (C) stocks in the Tierra Colectiva (TC) of Ipetí-Emberá in 2004 represents a 47% reduction from the estimated C stock at the onset of settlement in the early 1970’s. Results from the participatory assessments predict that, in 2024 and in absence of a CDM project, the C stocks will decline from 301,859 t C in 2004 to 155,730 t C, which constitutes a reduction of 52%. The scenario with CDM estimates C stocks of 305,853 t C for 2024, a value slightly superior to the 2004 value. In the TC there is ground to believe that cattle ranching is likely to become an ever more important activity as the population is young and growing and cannot easily move elsewhere. Forests tend to be cleared for cultivation while pastures are established on short fallows. Our baseline scenario underlines the potential for a CDM project to make a significant difference in the future C stocks of this landscape.  相似文献   
4.
Cadmium solubility and sorption in an arable clay loam soil that had received sewage sludge for 41 years were compared to an unsludged control in batch studies. Soil pH dominated Cd sorption, explaining >92% of the variation in Kd values in both treatments. At any pH, Cd sorption was apparently slightly but significantly (p < 0.05) smaller in the sludge-amended soil compared to the control, even though the organic carbon content was 70% larger and the ammonium oxalate-extractable iron content was roughly doubled. Correction for dissolved organic carbon (DOC) complexation with the speciation model WHAM reduced the difference in sorption between treatments, but the sludged soil still had significantly smaller Kd values (p < 0.01). Batch equilibrations without addition of Cd showed that there was no significant difference in the solubility of "native" cadmium (defined as EDTA-extractable Cd) in sludged and control soils. The reason for the lack of increase in Cd sorption in the sludge-amended soil has not been established, but it may be due to competition for sorption sites on humic compounds with sludge-derived Fe and trace metals such as zinc. The fact that the pyrophosphate-extractable (i.e., organically associated) iron content was seven times larger in the sludged soil provides some supporting evidence for this hypothesis.  相似文献   
5.
6.
There are fears that global warming will lead to degradation of peatlands, higher emissions of greenhouse gases from peat, and accelerated warming. Anaerobic decomposition of organic soils produces methane (CH4), a potent greenhouse gas. Two peat bogs differing in mean annual temperature, Velke Darko (VD, Czech Republic, 7.2 °C), and Stor Åmyran (SA, Sweden, 4.0 °C), were selected for a comparative study of how organic soils in different climatic zones will respond to warmer and drier conditions. Twenty peat cores from each bog were incubated in growth chambers. Under present-day summer conditions, VD produced 14 times more CH4 than SA. Two different warming scenarios were used. Peat-core replicates were kept at temperatures of 11 versus 16 °C, and 11 versus 22 °C. From 11 to 16 °C, the CH4 production slightly decreased at SA, and slightly increased at VD. From 11 to 22 °C, the CH4 production increased 9 times at SA, but slightly decreased at VD. After an 8-month incubation, peat cores under drying conditions (water table at ?14 cm) were compared to samples with original water table (?2 cm). Drying conditions led to a steeper reduction in CH4 production at VD, compared to SA. The CH4 production decreased more than 100 times at VD. Then, the combined effect of simultaneous warming and drying at 11 and 22 °C was studied. We did not find any significant effect of interactions between increasing temperature and decreasing water table level. Overall, the warmer site VD responded more strongly to the simulated climate change than the colder site SA.  相似文献   
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8.
Amendment of agricultural soils with municipal sewage sludges provides a valuable source of plant nutrients and organic matter. Nevertheless, addition of heavy metals and risks of eutrophication continue to be of concern. Metal behaviour in soils and plant uptake are dependent on the nature of the metal, sludge/soil physico-chemical properties and plant species. A pot experiment was carried out to evaluate plant production and heavy metal uptake, soil heavy metal pools and bioavailability, and soil P pools and possible leaching losses, in agricultural soils amended with sewage sludge for at least 10 years (F20) compared to non-amended soils (control). Sewage sludge application increased soil pH, N, Olsen-extractable-P, DOC and exchangeable Ca, Mg and K concentrations. Total and EDTA-extractable soil concentrations of Cu and Zn were also significantly greater in F20, and soil metal (Cu, Mn and Zn) and P fractionation altered. Compared to the control, in F20 relative amounts of acid-extractable (Mn, Zn), reducible (Mn, Zn) and oxidisable (Cu, Zn) metal fractions were greater, and a dominance of inorganic P forms was observed. Analyses of F20 soil solutions highlighted risks of PO4 and Cu leaching. However, despite the observed increases in metal bioavailability sewage sludge applications did not lead to an increase in plant shoot concentrations (in wild plants or crop species). On the contrary, depending on the plant species, Mn and Zn tissue concentrations were within the deficiency level for most plants.  相似文献   
9.
The occurrence of five pharmaceuticals, consisting of four anti-inflammatory and one antiepileptic drug, was studied by passive sampling and grab sampling in northern Lake Päijänne and River Vantaa. The passive sampling was performed by using Chemcatcher® sampler with a SDB-RPS Empore disk as a receiving phase. In Lake Päijänne, the sampling was conducted during summer 2013 at four locations near the discharge point of a wastewater treatment plant and in the years 2013 and 2015 at four locations along River Vantaa. The samples were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in the multiple reaction monitoring mode. The concentrations of carbamazepine, diclofenac, ibuprofen, ketoprofen, and naproxen in Lake Päijänne determined by passive sampling ranged between 1.4–2.9 ng L?1, 15–35 ng L?1, 13–31 ng L?1, 16–27 ng L?1, and 3.3–32 ng L?1, respectively. Similarly, the results in River Vantaa ranged between 1.2–40 ng L?1, 15–65 ng L?1, 13–33 ng L?1, 16–31 ng L?1, and 3.3–6.4 ng L?1. The results suggest that the Chemcatcher passive samplers are suitable for detecting pharmaceuticals in lake and river waters.  相似文献   
10.
Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops: the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields. Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model 4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge, on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions of climate change, which increased from 7.47 t DW ha−1 a−1 under the recent climate to 9.26 t DW ha−1 a−1 at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha−1 a−1 under the recent climate and could rise up to 0.93 t C ha−1 a−1 under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations are a suitable contribution to regional CO2 mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget are possible.  相似文献   
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