As climates change across already stressed ecosystems, there is no doubt that species will be affected, but to what extent and which will be most vulnerable remain uncertain. The fossil record suggests that most species persisted through past climate change, whereas forecasts of future impacts predict large-scale range reduction and extinction. Many species have altered range limits and phenoty...

climate is the most important factor which control desertification .in order to detect climate changes in desert zones, time trend analysis is applied to extreme indices in kashan station using extreme climate index software (ecis). results show significant trends in extreme indices during the past decade 1995-2004 and the pronounced warming is associated with a negative trend in cold extremes....

climate change is a complicated issue with many factors playing role in its formation and distribution. considering this complication, a comprehensive and holistic approach is needed for a better understanding and management of those factors. the causal frameworks are among systemic and integrated methods for addressing the causes of environmental problems and the relationships that exist betwe...

Species can either adapt to new conditions induced by climate change or shift their range in an attempt to track optimal environmental conditions. During current range shifts, species are simultaneously confronted with a second major anthropogenic disturbance, landscape fragmentation. Using individual-based models with a shifting climate window, we examine the effect of different rates of clima...

the agricultural sector was affected by climate change more than every other sectors, because it is close to nature. in other words, the effects of climate change were been on the farmers’ livelihood. farmers need to entrepreneurial changes for adaptation to climate change in their livelihood. hence, investigation of farmers’ entrepreneurial behavior in response to climate change was the main p...

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â â â  â â  â  abstract â  this paper examines the two most important current efforts to devise new rules binding all nations the negotiations in the wto of trade rules and the negotiations under the un framework convention on climate change to devise rules restricting the annual emissions of greenhouse gases. both negotiations have failed after several years of intensive effort. there are rema...