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991.
We present a methodology for using a domestic water use time series that were obtained from Yellow River Conservancy Commission, together with the climatic records from the National Climate Center of China to evaluate the effects of climate variability on water use in the Yellow River Basin. A suit of seven Global Circulation Models (GCMs) were adopted to anticipate future climate patterns in the Yellow River. The historical records showed evidences of rises in temperature and subsequent rises in domestic water demand in the basin. For Upstream of Longyangxia region, the impact was the least, with only 0.0021?×?108 m3 for a temperature increase of 1 °C; while for Longyangxia-Lanzhou region, domestic water use was found to increase to 0.18?×?108 m3 when temperature increases 1 °C. Downstream of Huayuankou was the region with the most changes in temperature that gave the highest increase of 1.95?×?108 m3 in domestic water demand for 1 °C of change of temperature. Downstream of Huayuankou was identified as the most vulnerable area, where domestic water demand increases nearly by 42.2 % with 1 °C increase of temperature. Judging from the trends of temperature range, we concluded that future temperature in Yellow River Basin has an increasing tendency. This could worsen the existing issues of domestic water demand and even more to trigger high competition among different water-using sectors.  相似文献   
992.
There is a growing demand for alternatives to Sweden’s current dominant silvicultural system, driven by a desire to raise biomass production, meet environmental goals and mitigate climate change. However, moving towards diversified forest management that deviates from well established silvicultural practices carries many uncertainties and risks. Adaptive management is often suggested as an effective means of managing in the context of such complexities. Yet there has been scepticism over its appropriateness in cases characterised by large spatial extents, extended temporal scales and complex land ownership—characteristics typical of Swedish forestry. Drawing on published research, including a new paradigm for adaptive management, we indicate how common pitfalls can be avoided during implementation. We indicate the investment, infrastructure, and considerations necessary to benefit from adaptive management. In doing so, we show how this approach could offer a pragmatic operational model for managing the uncertainties, risks and obstacles associated with new silvicultural systems and the challenges facing Swedish forestry.  相似文献   
993.
GOAL, SCOPE AND BACKGROUND: Pentachlorophenol (PCP) is the second highest volume pesticide used in the United States. It is a mutagenic compound whose exposure poses significant health effects, One of the most desirable, environmentally friendly treatment methods is bioremediation. For soil-based contamination, the effectiveness of bioremediation will also be affected by the presence of an active indigenous population, sorption of the contaminant onto the soil, and environmental parameters. METHODS: Two pure strains and their mixed culture were used to evaluate PCP biodegradation in two different field soils, Columbia (CO) and New Mexico (NM). Biostimulation of the indigenous microbes was evaluated by adding nutrients. The efficiency of adding bacteria strains (bioaugmentation) for degrading PCP was determined with Arthrobacter sp., Flavobacterium sp. and a 50:50 mixture of the two bacteria strains. RESULTS: In CO soil, only 24%, 12% and 25% of the initial PCP concentration were degraded by Flavobacterium sp., Arthrobacter sp. and mixed culture, respectively. Arthrobacter sp. was used in NM soil with two initial concentrations and achieved degradation efficiencies of 57% and 61% for 361 and 95 mg kg- concentrations, respectively. Discussion. Analysis via statistical methods showed that the bacteria had different efficiencies on PCP degradation in each soil. 2 CONCLUSIONS: All bacteria catalyzed a higher PCP degradation when present in NM soil. Second, Flavobacterium sp. degraded more PCP than Arthrobacter sp. in CO soil. The mixed culture achieved the highest degradation efficiency regardless of the initial concentration or soil origin. RECOMMENDATIONS AND PERSPECTIVES: The effect of the soil properties, such as the soil organic matter (SOM) on PCP biodegradation should be investigated. Future work can also investigate the effect of aging time on biodegradation.  相似文献   
994.
This article measures the changes in energy use, blue water footprint, and greenhouse gas (GHG) emissions associated with shifting from current US food consumption patterns to three dietary scenarios, which are based, in part, on the 2010 USDA Dietary Guidelines (US Department of Agriculture and US Department of Health and Human Services in Dietary Guidelines for Americans, 2010, 7th edn, US Government Printing Office, Washington, 2010). Amidst the current overweight and obesity epidemic in the USA, the Dietary Guidelines provide food and beverage recommendations that are intended to help individuals achieve and maintain healthy weight. The three dietary scenarios we examine include (1) reducing Caloric intake levels to achieve “normal” weight without shifting food mix, (2) switching current food mix to USDA recommended food patterns, without reducing Caloric intake, and (3) reducing Caloric intake levels and shifting current food mix to USDA recommended food patterns, which support healthy weight. This study finds that shifting from the current US diet to dietary Scenario 1 decreases energy use, blue water footprint, and GHG emissions by around 9 %, while shifting to dietary Scenario 2 increases energy use by 43 %, blue water footprint by 16 %, and GHG emissions by 11 %. Shifting to dietary Scenario 3, which accounts for both reduced Caloric intake and a shift to the USDA recommended food mix, increases energy use by 38 %, blue water footprint by 10 %, and GHG emissions by 6 %. These perhaps counterintuitive results are primarily due to USDA recommendations for greater Caloric intake of fruits, vegetables, dairy, and fish/seafood, which have relatively high resource use and emissions per Calorie.  相似文献   
995.
Deforestation and oil palm expansion in Central Kalimantan province are among the highest in Indonesia. This study examines the physical and monetary impacts of oil palm expansion in Central Kalimantan up to 2025 under three policy scenarios. Our modelling approach combines a spatial logistic regression model with a set of rules governing land use change as a function of the policy scenario. Our physical and monetary analyses include palm oil expansion and five other ecosystem services: timber, rattan, paddy rice, carbon sequestration, and orangutan habitat (the last service is analysed in physical units only). In monetary terms, our analysis comprises the contribution of land and ecosystems to economic production, as measured according to the valuation approach of the System of National Accounts. We focus our analysis on government-owned land which covers around 97 % of the province, where the main policy issues are. We show that, in the business-as-usual scenario, the societal costs of carbon emissions and the loss of other ecosystem services far exceed the benefits from increased oil palm production. This is, in particular, related to the conversion of peatlands. We also show that, for Central Kalimantan, the moratorium scenario, which is modelled based on the moratorium currently in place in Indonesia, generates important economic benefits compared to the business-as-usual scenario. In the moratorium scenario, however, there is still conversion of forest to plantation and associated loss of ecosystem services. We developed an alternative, sustainable production scenario based on an ecosystem services approach and show that this policy scenario leads to higher net social benefits including some more space for oil palm expansion.  相似文献   
996.
This study analyzes the sources of income inequality among ethnic minorities in the Northwest region—the poorest and highest inequality region of Vietnam. Using an analysis of Gini decomposition by income source, the results show that while agricultural income, notably crop income, considerably decreases income inequality, off-farm income sources (wage and non-farm self-employment incomes) are found to increase inequality. This can be explained that in comparison with other income sources, agricultural income is more equally distributed and the main income source for most poor households. However, off-farm income sources are more unequally distributed and flow disproportionately toward the better-off. The findings support the hypothesis that income diversification in non-farm activities results in either greater inequality if opportunities for these activities are skewed toward to the better-off or less inequality if such opportunities are accessible to the poorer part of the population.  相似文献   
997.
When reproductive success is constant in one breeding phase, different tactics that increase variation in reproductive success among individuals may evolve in other phases. For instance, in shorebirds, which usually have a limited clutch size of four eggs, variation in reproductive tactics among individuals is expected either before egg-laying (e.g. diverse mating systems) or after hatching of the young (e.g. diverse parental care). In this paper, I studied the pied avocet (Recurvirostra avosetta), a shorebird with a modal clutch size of four eggs, to test whether post-hatch chick adoption as an alternative tactic can be linked to increased variation in annual reproductive success. When predation was high, naturally adopting pairs produced more filial fledglings than did pairs not adopting chicks and not losing chicks to adoption. The number of filial fledglings increased with the number of adopted young, possibly through diluting the chances of predation on filial young. Experimental chick addition did not lead to more fledged young due to low brood integrity as shown by the frequent loss of chicks from some experimental broods. When predation was low, larger broods occupied feeding territories with higher prey abundance than smaller broods, possibly due to their dominance over smaller ones. Pairs that lost chicks to adoption (donors) fledged as many filial young in their broods as did non-adopters/non-donors, whereas the total number of donors’ filial fledglings, including those raised in adopting broods, approached that of adopters. These findings show, for the first time, that post-hatch alternative reproductive tactics can lead to variation in annual reproductive success and to higher success for some pairs even in species where past adaptations limit variation in reproductive success in a certain phase of reproduction.  相似文献   
998.
We studied the removal mechanism and affecting factors of Fe2+-based replacement–precipitation process for treating CuEDTA-containing wastewaters. Since Fe2+ was easily oxidized to Fe3+ in the presence of oxygen, the chelated copper was removed by the synergetic effect of Fe3+ replacement and NaOH precipitation. Our experiments showed that the copper removal efficiency was considerably dependant on pH conditions of the solution and molar ratio of Fe2+/Cu2+.  相似文献   
999.
Distribution, abundance and age of diapause eggs from three species of calanoid copepods (in particular from Acartia spp. most likely Acartia tonsa, and Centropages hamatus and less numerous from Temora longicornis) were recorded in sediment profiles by enumerating hatched nauplii from incubated sediment samples. Phytoplankton pigments and 210Pb and 137Cs analyses indicated that the sedimentation regimes were different between two southern and two northern stations of the island Funen, Denmark. Significant variations in vertical distribution, abundance and mortality of diapause eggs were found between the stations. Dating of the sediment cores suggested a ~70-year maximum age of viable eggs on the northernmost stations, and ~28 year at the southernmost stations. The eggs exhibited a significantly higher mortality rate at the southernmost stations compared with the northernmost, 0.35–0.53 year−1 vs. 0.07–0.08 year−1 with no systematic pattern among species. The differences in abundance, mortality and age of the diapause eggs are suggested to be due to the sediment characteristics in which they are buried.  相似文献   
1000.
Environmental Science and Pollution Research - Solar energy is a vast renewable energy source, but uncertainty in the demand and supply of energy due to various geographical regions raises a...  相似文献   
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