29
Aug
(Beyond Pesticides, August 29, 2007) Entomologists have recently begun studying whether increasing temperatures will attract more insects to the New England region, as scientists have begun reporting the appearance of new and more numerous unwanted insects. The colder winters of the New England region have historically limited insect populations, but in recent years as temperatures have warmed, the amount and variety of pests have increased. According to the government’s U.S. Global Change Research Program, in its New England Regional Assessment of the Potential Consequences of Climate Variability and Change, “A warming New England region (especially warming winters) will support the introduction and expansion of exotic pests into the region.” Although scientists cannot definitively say that there is a relationship between increasing temperatures in the region and an increase in the number of insects, Vermont entomologist Jon Turmel, points out that ticks carrying lyme disease, as well as mosquitoes with West Nile virus (WNv) and encephalitis have been reported in the state. The Aedes japonicus, an Asian mosquito species, was first reported in Vermont five years ago. These mosquitoes can spread Japanese and St. Louis encephalitis, which are viral brain infections that can result in death, along with WNv. Reported cases […]
Posted in Climate Change, Insect-Borne Disease | No Comments »
23
Jul
(Beyond Pesticides, July 23, 2007) New research finds several species of freshwater fish have lower temperature tolerances when exposed to the widely used pesticides endosulfan and chlorpyrifos. The discovery reveals another key pesticides issue in the global warming debate. The study, “The Effects of Three Organic Chemicals on the Upper Thermal Tolerances of Four Freshwater Fishes” (Environmental Toxicology and Chemistry, July 2007), is the work of Ronald Patra of Australia’s Department of Environment and Conservation and colleagues. The study establishes the upper temperature tolerances of both unexposed and exposed silver perch, eastern rainbowfish, western carp gudgeon and rainbow trout. Exposed fish were given sublethal doses of endosulfan, chlorpyrifos or phenol. The results show exposure to endosulfan cause a decrease of temperature tolerance in silver perch by 2.8 °C, eastern rainbowfish 4.1 °C, western carp gudgeon 3.1 °C, and rainbow trout 4.8 °C. Chlorpyrifos decreases temperature tolerance in silver perch by 3.8 °C, eastern rainbowfish 2.5 °C, western carp gudgeon 4.3 °C, and rainbow trout 5.9 °C. Phenol is not shown to cause a significant decrease in tolerance. The authors conclude, “The reduction in thermal tolerance of fish in the presence of endosulfan and chlorpyrifos suggest that, not only does temperature […]
Posted in Chlorpyrifos, Climate Change, Endosulfan, Wildlife/Endangered Sp. | No Comments »
29
Mar
(Beyond Pesticides, March 29, 2007) While it seems to allergy-sufferers that symptoms get worse year after year, most figure it’s all in our heads. However, research by Lewis Ziska, Ph.D., a plant physiologist with the USDA Agricultural Research Service’s Crop Systems and Global Change Lab and speaker at the upcoming National Pesticide Forum, shows that common pollen allergens – including the troublesome ragweed pollen – may be getting worse as a result of global climate change. The conventional response to unwanted plants is increased pesticide use, which raises concerns among environmental and public health advocates. According to Dr. Ziska’s research, elevated levels of carbon dioxide (CO2), the top greenhouse gas, and warmer temperatures appear to increase ragweed pollen production. Dr. Ziska’s research uses sealed growth chamber systems to simulate current levels of CO2 (370 parts per million by volume, ppmv) and that projected for the mid-21st century (600 ppmv). The ragweed increased pollen productivity by 131 and 3200% respectively, compared to ragweed grown at pre-industrial CO2 levels (280 ppmv). A recent two-year real-world observational study of ragweed also found that urbanization-induced increases in CO2 and temperature were associated with increased ragweed growth, pollen production and pollen allergenicity, suggesting a probable […]
Posted in Chemicals, Climate Change, Disease/Health Effects, Glyphosate | No Comments »
19
Mar
(Beyond Pesticides, March 19, 2007) Stanford University and Lawrence Livermore National Laboratory researchers are publishing a study saying that some of the world’s farms are yielding markedly fewer crops because of global warming, according to the San Jose Mercury News. Meanwhile, providing further evidence that the pace of global warming is accelerating, scientists announced last week that this winter was the hottest on record – and that surface temperatures around the world have been increasing at three times the rate they were before 1976. This warming most likely is costing the planet $5 billion annually in losses to three of the six major food crops, the Stanford and Lawrence Livermore researchers say. The study warns that wheat, corn and barley are especially affected, with 40 million fewer metric tons of the crops produced each year. For every 1 degree increase in temperature, the researchers say, crop yields drop by about 3 percent to 5 percent, and the decline is clearly caused by human activity. “Global warming is having real impacts – and we’re seeing their effects already,” said Chris Field, one of the authors of the crop study, and director of the department of global ecology at Stanford’s Carnegie Institution. […]
Posted in Climate Change, Insect-Borne Disease | 3 Comments »
