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991.
The persistence of fenamiphos (nematicide) in five soils collected from different geographical regions such as Australia, Ecuador and India under three temperature regimes (18, 25 and 37°C) simulating typical environmental conditions was studied. The effect of soil properties (soil pH, temperature and microbial biomass) on the degradation of fenamiphos was determined. The rate of degradation increased with increase in temperature. Fenamiphos degradation was higher at 37°C than at 25 and 18°C (except under alkaline pH). The degradation pathway differed in different soils. Fenamiphos sulfoxide (FSO) was identified as the major degradation product in all the soils. Fenamiphos sulfone (FSO2), and the corresponding phenols: fenamiphos phenol (FP), fenamiphos sulfoxide phenol (FSOP) and fenamiphos sulfone phenol (FSO2P) were also detected. The degradation of fenamiphos was faster in the alkaline soils, followed by neutral and acidic soils. Under sterile conditions, the dissipation of the pesticide was slower than in the non-sterile soils suggesting microbial role in the pesticide degradation. The generation of new knowledge on fenamiphos degradation patterns under different environmental conditions is important to achieve better pesticide risk management.  相似文献   
992.
ABSTRACT

The study found that encountering new information in an online chat rather than information that participants already knew and were familiar with was more likely to reduce support for the view that climate change is due to anthropogenic causes, even though the majority of the presented information supported anthropogenic causes. Participants reported feeling more competent and knowledgeable about the topic and felt less ostracized from others in the chat when participants were already familiar with information others discussed than when information discussed by others in the chat was new information. However, they viewed other chat members as more competent and knowledgeable when those others mentioned new information. Results are discussed within knowledge deficit model of science communication and the bias for common information.  相似文献   
993.
Abstract: Species that have temperature‐dependent sex determination (TSD) often produce highly skewed offspring sex ratios contrary to long‐standing theoretical predictions. This ecological enigma has provoked concern that climate change may induce the production of single‐sex generations and hence lead to population extirpation. All species of sea turtles exhibit TSD, many are already endangered, and most already produce sex ratios skewed to the sex produced at warmer temperatures (females). We tracked male loggerhead turtles (Caretta caretta) from Zakynthos, Greece, throughout the entire interval between successive breeding seasons and identified individuals on their breeding grounds, using photoidentification, to determine breeding periodicity and operational sex ratios. Males returned to breed at least twice as frequently as females. We estimated that the hatchling sex ratio of 70:30 female to male for this rookery will translate into an overall operational sex ratio (OSR) (i.e., ratio of total number of males vs females breeding each year) of close to 50:50 female to male. We followed three male turtles for between 10 and 12 months during which time they all traveled back to the breeding grounds. Flipper tagging revealed the proportion of females returning to nest after intervals of 1, 2, 3, and 4 years were 0.21, 0.38, 0.29, and 0.12, respectively (mean interval 2.3 years). A further nine male turtles were tracked for short periods to determine their departure date from the breeding grounds. These departure dates were combined with a photoidentification data set of 165 individuals identified on in‐water transect surveys at the start of the breeding season to develop a statistical model of the population dynamics. This model produced a maximum likelihood estimate that males visit the breeding site 2.6 times more often than females (95%CI 2.1, 3.1), which was consistent with the data from satellite tracking and flipper tagging. Increased frequency of male breeding will help ameliorate female‐biased hatchling sex ratios. Combined with the ability of males to fertilize the eggs of many females and for females to store sperm to fertilize many clutches, our results imply that effects of climate change on the viability of sea turtle populations are likely to be less acute than previously suspected.  相似文献   
994.
Abstract: Predicting whether the ranges of tropical species will shift to higher elevations in response to climate change requires models that incorporate data on topography and land use. We incorporated temperature gradients and land‐cover data from the current ranges of species in a model of range shifts in response to climate change. We tested four possible scenarios of amphibian movement on a tropical mountain: movement upslope through and to land cover suitable for the species; movement upslope to land‐cover types that will not sustain survival and reproduction; movement upslope to areas that previously were outside the species’ range; and movement upslope to cooler areas within the current range. Areas in the final scenario will become isolated as climate continues to change. In our scenarios more than 30% of the range of 21 of 46 amphibian species in the tropical Sierra Nevada de Santa Marta is likely to become isolated as climate changes. More than 30% of the range of 13 amphibian species would shift to areas that currently are unlikely to sustain survival and reproduction. Combined, over 70% of the current range of seven species would become thermally isolated or shift to areas that currently are unlikely to support survival and reproduction. The constraints on species’ movements to higher elevations in response to climate change can increase considerably the number of species threatened by climate change in tropical mountains.  相似文献   
995.
Researchers are looking for an effective solution to mitigate climate change along with the growth of global average temperature and the frequent occurrence of extreme climate disasters. However, after the ratification of Kyoto Protocol, which is the international agreement dedicated to solve the problem, climate change is getting more serious in the recent decade. It is considered that the ultimate reason is not from the limitation of current technology or policy instrument but from the cognition part, which is the basis guiding people to comprehend problems and search for solutions. Until now, the research on the climate change issue is consistently based on a deficient assumption that climate change is a kind of “the tragedy of the commons.” This phenomenon could be considered as the “Pluto phenomenon” and directly cause the inefficiency of current solution. Therefore, the cognition's reconstruction is vital to guide researchers and relevant stakeholders to search for an efficient approach to mitigate climate change.  相似文献   
996.
997.
Abstract: Even under the most optimistic scenarios, during the next century human‐caused climate change will threaten many wild populations and species. The most useful conservation response is to enlarge and link protected areas to support range shifts by plants and animals. To prioritize land for reserves and linkages, some scientists attempt to chain together four highly uncertain models (emission scenarios, global air–ocean circulation, regional circulation, and biotic response). This approach has high risk of error propagation and compounding and produces outputs at a coarser scale than conservation decisions. Instead, we advocate identifying land facets—recurring landscape units with uniform topographic and soil attributes—and designing reserves and linkages for diversity and interspersion of these units. This coarse‐filter approach would conserve the arenas of biological activity, rather than the temporary occupants of those arenas. Integrative, context‐sensitive variables, such as insolation and topographic wetness, are useful for defining land facets. Classification procedures such as k‐means or fuzzy clustering are a good way to define land facets because they can analyze millions of pixels and are insensitive to case order. In regions lacking useful soil maps, river systems or riparian plants can indicate important facets. Conservation planners should set higher representation targets for rare and distinctive facets. High interspersion of land facets can promote ecological processes, evolutionary interaction, and range shift. Relevant studies suggest land‐facet diversity is a good surrogate for today's biodiversity, but fails to conserve some species. To minimize such failures, a reserve design based on land facets should complement, rather than replace, other approaches. Designs based on land facets are not biased toward data‐rich areas and can be applied where no maps of land cover exist.  相似文献   
998.
The results of regression and correlation analyses of long-term data (1971–2005) on the dates of arrival of 16 bird species to the Il’men State Nature Reserve (the Southern Urals) show that they have not changed in most of these birds, unlike in many countries of Europe and North America. This is explained primarily by the absence of any significant trends in the dynamics of spring air temperatures in the study region. Only the herring gull Larus argentatus and the lapwing Vanellus vanellus have shown a significant tendency to arrive earlier, while the garganey Anas querquedula has shown a tendency to arrive on later dates in the past two decades. Nevertheless, interannual fluctuations in the dates of arrival are well manifested in both early arriving species wintering in Europe and late-arriving species wintering in Africa. These fluctuations largely depend on temperature conditions in spring. As a rule, almost all species studied—from waterbirds to passerines—appear in the Il’men Reserve earlier in years with early and warm springs than in cold years. Hence, spring weather is the key factor determining the dates of arrival of migratory birds to the study region.  相似文献   
999.
Establishing positive and urgent targets for CO2 reduction and emission peak, and promoting energy conservation and energy structure adjustment are among the strategies to address global climate change and CO2 emissions reduction. They are also means to break through the constraints of domestic resources and environment, and internal needs, to achieve sustainable development. Generally speaking, a country's CO2 emission peak appears after achieving urbanization and industrialization. By then, connotative economic growth will appear, GDP will grow slowly, energy consumption elasticity will decrease, and energy consumption growth will slow down – dependent mainly on new and renewable energies. Fossil fuel consumption will not increase further. When CO2 emission reaches its peak, the annual reduction rate of CO2 intensity of GDP is greater than GDP annual growth rate; and the annual reduction rate of CO2 intensity of energy use is greater than the annual growth rate of energy consumption. Therefore, three important approaches to promotion of CO2 emission peak can be concluded: maintaining reasonable control of GDP growth, strengthening energy conservation to significantly reduce the GDP energy intensity, and optimizing the energy mix to reduce the CO2 intensity of energy use. By around 2030, China will basically have completed its rapid development phase of industrialization and urbanization. Connotative economic growth will appear with the acceleration of industrial structure adjustment. The target of GDP energy intensity will still be to maintain an average annual reduction of 3% or higher. The proportion of non-fossil fuels will reach 20–25%, and the aim will be to maintain an average annual growth rate of 6–8%. The total annual energy demand growth of 1.5% will be satisfied by the newly increased supply of non-fossil fuels. The annual decline in CO2 intensity of GDP will reach 4.5% or higher, which is compatible with an average annual GDP growth rate of approximately 4.5% in order to reach CO2 emission peak. This corresponds to the level of China's potential economic growth. Achieving CO2 emission peak will not impose a rigid constraint on economic development, but rather promote economic development and accelerate the transformation of green, low-carbon development. The CO2 emission peak can be controlled with a cap of 11 billion tons, which means that CO2 emission will increase by less than 50% compared with 2010. The per capita emission peak will be controlled at a level of less than 8 tons, which is lower than the 9.5 tons in the EU and Japan and much lower than the 20 tons in the US, future economic and social development faces many uncertainties in achieving the CO2 emission peak discussed above. It depends on current and future strategies and policies, as well as the pace and strength of economic transformation, innovation, and new energy technologies. If the economic transformation pattern fails to meet expectations, the time required to reach CO2 emission peak would be delayed and the peak level would be higher than expected. Therefore, we need to coordinate thoughts and ideas and deploy these in advance; to highlight the strategic position of low-carbon development and its priorities; to enact mid- to long-term energy development strategies; and to establish and improve a system of laws, regulations, and policies as well as an implementation mechanism for green, low-carbon development. Oriented by positive and urgent CO2 reduction and peak targets, the government would form a reversed mechanism to promote economic transformation and embark on the path of green, low-carbon development as soon as possible.  相似文献   
1000.
ABSTRACT

Does climate change lead to violent conflict? This article reviews the existing literature connecting climatic conditions to conflict. It finds that the existing literature has not detected a robust and general effect from climate to conflict onset. Moreover, there exists scientific agreement that climatic changes can contribute to conflict under some conditions and through certain pathways. In particular, the recent literature offers considerable suggestive evidence that climatic changes can lead to conflict in countries and/or regions, which are dependent on agriculture, host politically excluded groups, and have ineffective institutions. Future research should focus not only on understanding of the pathways and contexts in which climatic changes are most likely to increase or exacerbate the risk of conflict but also work to understand the mechanisms by which climate variability and change might cause conflict.  相似文献   
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