Afrane Yaw A, Zhou Goufa, Lawson Bernard W, Githeko Andrew K, Yan Guiyun
Climate and Human Health Research Unit, Centre for Vector Biology and Control Research, Kenya Medical Research Institute, Kenya.
Am J Trop Med Hyg. 2006 May;74(5):772-8.
Land use changes have been suggested as one of the causes for malaria epidemics in the African highlands. This study investigated the effects of deforestation-induced changes in indoor temperature on the survivorship and reproductive fitness of Anopheles gambiae in an epidemic prone area in the western Kenya highlands. We found that the mean indoor temperatures of houses located in the deforested area were 1.2 degrees C higher than in houses located in the forested area during the dry season and 0.7 degrees C higher during the rainy season. The mosquito mortality rate was highly age-dependent regardless of study site or season. Mosquitoes that were placed in houses in the deforested area showed a 64.8-79.5% higher fecundity than those in houses located in the forested area, but the median survival time was reduced by 5-7 days. Female mosquitoes in the deforested area showed a 38.5-40.6% increase in net reproductive rate and an 11.6-42.9% increase in intrinsic growth rate than those in the forested area. Significant increases in net reproductive rate and intrinsic growth rate for mosquitoes in the deforested area suggest that deforestation enhances mosquito reproductive fitness, increasing mosquito population growth potential in the western Kenya highlands. The vectorial capacity of An. gambiae under study was estimated at least 106% and 29% higher in the deforested area than in the forested area in dry and rainy seasons, respectively.
土地利用变化被认为是非洲高地疟疾流行的原因之一。本研究调查了肯尼亚西部高地一个易发生疫情地区森林砍伐引起的室内温度变化对冈比亚按蚊生存和繁殖适应性的影响。我们发现，在旱季，位于森林砍伐地区房屋的室内平均温度比位于森林地区房屋的室内平均温度高1.2摄氏度，在雨季则高0.7摄氏度。无论研究地点或季节如何，蚊子的死亡率都高度依赖于年龄。放置在森林砍伐地区房屋中的蚊子的繁殖力比放置在森林地区房屋中的蚊子高64.8 - 79.5%，但中位生存时间减少了5 - 7天。森林砍伐地区的雌性蚊子的净繁殖率比森林地区的雌性蚊子高38.5 - 40.6%，内在增长率高11.6 - 42.9%。森林砍伐地区蚊子的净繁殖率和内在增长率显著增加，这表明森林砍伐提高了蚊子的繁殖适应性，增加了肯尼亚西部高地蚊子种群的增长潜力。在旱季和雨季，研究中的冈比亚按蚊的媒介能量估计在森林砍伐地区分别比在森林地区至少高106%和29%。
