Southeast Asian countries are confronting climate variability, challenging agricultural sustainability and rural livelihoods. However, little research effort has been devoted to exploring how farmers in those countries perceive climate variability and how the perceptions link to adaptive responses. This paper deploys information from three focus group discussions with 30 male farmers; and six in-depth interviews with one female and five male agricultural officers in the Mekong Delta, Vietnam. Recorded 34-year meteorological data in the delta from 1978 to 2011 is also incorporated to demonstrate the actual climate variability of the region. We find that farmers are becoming increasingly conscious of local climate variability issues. However, they have limited understanding of the importance of adaptation to their livelihoods. They also have limited knowledge of where and who to contact for appropriate climate change adaptation information. No opinions about the link between global warming and local climate variability and change were observed. Casual observation via public media and personal experience dominated farmers’ sources of information. Barriers to farmers’ adaptation are not exclusively restricted to socio-economic factors and resource constraints; e.g. land tenure, technical knowledge, market, social relationship, credit, information, health care, and demographics. Maladaptation, habit, and the perception of the importance of climate variability and adaptation are found as additional constraints. Observed differences in farmers’ and agricultural officers’ perspectives regarding barriers to farmers’ adaptation suggest important policy implications. 相似文献
The attraction of sexual partners is a vital necessity among insects, and it involves conflict of interests and complex communication systems among male and female. In this study, we investigated the developing of sexual attractiveness in virgin queens (i.e., gynes) of Melipona flavolineata, an eusocial stingless bee. We followed the development of sexual attractiveness in 64 gynes, belonging to seven age classes (0, 3, 6, 9, 15, 18 days post-emergence), and we also evaluated the effect of different social interactions (such as competition between queens and interactions with workers) on the development of attractiveness in other 60 gynes. We used the number of males that tried to mate with a focal gyne as a representative variable of its sexual attractiveness. During the essays, each gyne was individually presented to 10 sexually mature males, and during 3 min, we counted the number of males that everted their genitalia in response to the presence of a gyne. Here, we show that M. flavolineata gynes are capable to (i) maintain their sexual attractiveness for long periods through adult life, (ii) they need a minimum social interaction to trigger the development of sexual attractiveness, and (iii) that gynes express this trait only within a social context. We conclude that the effective occurrence of matings is conditional on potential social interactions that gynes experienced before taking the nuptial flight, when they are still in the nest. These findings bring insights into the factors determining reproductive success in social insects. 相似文献
Journal of Material Cycles and Waste Management - This paper utilizes desulfurization ash (DA), fly ash (FA) and ordinary Portland cement (OPC) to prepare unfired high-strength road-base stones by... 相似文献
Human-induced urban growth and sprawl have implications for greenhouse gas (GHG) emissions that may not be included in conventional GHG accounting methods. Improved understanding of this issue requires use of interactive, spatial-explicit social–ecological systems modeling. This paper develops a comprehensive approach to modeling GHG emissions from urban developments, considering Stockholm County, Sweden as a case study. GHG projections to 2040 with a social–ecological system model yield overall greater emissions than simple extrapolations in official climate action planning. The most pronounced difference in emissions (39% higher) from energy use single-residence buildings resulting from urban sprawl. And this difference is not accounted for in the simple extrapolations. Scenario results indicate that a zoning policy, restricting urban development in certain areas, can mitigate 72% of the total emission effects of the model-projected urban sprawl. The study outcomes include a decision support interface for communicating results and policy implications with policymakers.
Fishponds are man-made shallow water bodies that are still little studied because of their small size. They represent high value ecosystems, both environmentally (biodiversity hotspot) and economically (fish production). They can have a high place on the hydrographic network, so their influence on water quality is of first importance for rivers and water bodies located downstream and monitored under the Water Framework Directive. These small water bodies can be a source of contaminants during draining period or an efficient buffer for pesticides. We wanted to evaluate whether these ponds could also be a remediation tool against metals by following the annual evolution of upstream/downstream flows. Cadmium, copper, lead and zinc concentrations were quantified in the dissolved phase upstream and downstream of three ponds, each one having a specific agricultural environment (traditional or organic). Metal concentration was quantified in sediments and water. For the dissolved phase, the predictive non-effect concentration was often exceeded, suggesting an environmental risk. Results highlighted also greater quantity of metals at the downstream of the pond compared to the upstream, suggesting remobilization into the ponds or direct cross-sectional contributions from the watershed (e.g. runoff from crops) or even remobilization. Regarding sediments, minimal contamination was shown but a high mineralogical variability. No buffer effect of ponds, which could reduce the risk of acute or chronic toxicity, was detected.
Environmental Science and Pollution Research - The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17... 相似文献