森林——你的健康醫(yī)師
來源:滬江聽寫酷
2011-01-24 01:14
眾所周知,保護雨林有益于保持生物多樣性??赡闶欠裰肋@也對人體健康大有益處?本周《新發(fā)傳染病》上刊登的一篇文章指出,這是因為砍伐樹木越少就有可能使瘧疾發(fā)作的越少。森林覆蓋面積僅減少4%就能使瘧疾發(fā)病率提高50%。
You know saving the rainforest is good for biodiversity. But it may also be a boon to human health. That's because less clear-cutting may mean less malaria, according to a paper out this week in the journal Emerging Infectious Diseases.
Researchers looked at stats for 2006 from 54 health districts in western Brazil. The sites had more than 15,000 cases of malaria. The investigators compared those cases to deforestation in the same health districts over the previous 10 years. They found that a loss of just four percent of forest cover was associated with nearly 50 percent more malaria cases. And malaria risk was highest five to 10 years after the jungle was cleared.
Not all mosquitoes carry malaria. But the human-loving species Anopheles darlingi does, and previous studies have shown that it thrives in disturbed areas. In fact, you're over 200 times more likely to find one of them biting you in a clearing than you are deep in the jungle, where other more benign species compete with them for blood.
So how much clear-cutting is too much? We don't know yet - but an intact swath of rainforest appears to provide free public health services.
-Christopher Intagliata
眾所周知,保護雨林有益于保持生物多樣性??赡闶欠裰肋@也對人體健康大有益處?本周《新發(fā)傳染病》上刊登的一篇文章指出,這是因為砍伐樹木越少就有可能使瘧疾發(fā)作的越少。
研究人員對巴西西部54個衛(wèi)生區(qū)在2006年的統(tǒng)計數(shù)據(jù)進行了研究,這些區(qū)域有15000多例瘧疾病患。研究人員將過去10年間同一衛(wèi)生區(qū)里的瘧疾病例與毀林開墾的情況作了比較,發(fā)現(xiàn)森林覆蓋面積僅減少4%就能使瘧疾發(fā)病率提高50%,而當這些熱帶叢林被砍伐殆盡的5至10年間,瘧疾的發(fā)病率升至最高點。
并非所有的蚊子都攜帶有瘧疾病毒。但酷愛叮人的達[林]氏按蚊可不是省油的燈,它們個個都攜帶瘧疾病毒,而且先前的研究表明它們在人類活動強干擾地區(qū)(林木砍伐嚴重地區(qū))更加肆虐。要知道,你在樹木全被砍伐而光的林地被這種蚊子叮上一口的幾率可是在叢林深處的200倍!密林莽叢中同樣嗜血的生物跟這些瘧蚊比起來可要仁慈得多。
那么,伐林砍木多少算是過度了呢?現(xiàn)在還不清楚——但是一片完整的雨林卻可以極大地改善公共健康哦。