Anthropologists and biologists have generally reasoned that high concentrations of melanin arose in the skin of peoples in tropical areas because it protected them against skin cancer 人类学家与生物学家通常是这麽推论的：热带族群的皮肤里，黑色素浓度很高，因为黑色素能保护他们不会得皮肤癌。
These human remains , after preliminary examination by physical anthropologists , were found to bear general characteristics of the mongolian race as well as those of certain race in tropical areas 经人类学者初步鉴定，在这批人骨可以指出某些亚洲蒙古人种的一般特徵，同时亦呈现出某些热带地区种族相近的特徵。
This paper discusses the trends and issues concerning agricultural informization of tropical areas and analyzes the underlying reasons by using relevant economic models of information economics 摘要论述了我国热带区域农业信息化的发展趋势及存在的问题，并运用信息经济学的相关模型对产生这些问题的深层次原因进行了分析。
If the forecasts hold true , it will be the first major ice storm to hit this semi - tropical area since 1997 when a blanket of ice disrupted traffic and led to the closing of airports , schools and many businesses 如果预测准确，就将会是自1997年来亚热带的地区遭遇首次大规模风暴，那时冰雪覆盖造成交通中断，及使机场、学校及许多企业停业。
If the forecasts hold true , it will be the first major ice storm to hit this semi - tropical area since 1997 when a blanket of ice disrupted traffic and led to the closing of airports , schools and many businesses 如果天气预报准确，这将是自1997年以来第一次袭击此半热带地区的冰降过程，在当时，冰降使交通中断，机场、学校和许多企业闭门营业。
If the forecasts hold true , it will be the first major ice storm to hit this semi - tropical area since 1997 when a blanket of ice disrupted traffic and led to the closing of airports , schools and many businesses 如果天气预报属实，这将是1997年以来第一场大冰暴袭击亚热带地区，冰雪覆盖路面严重阻碍交通，机场、学校和许多商业机构都要停止运营。
If the forecasts hold true , it will be the first major ice storm to hit this semi - tropical area since 1997 when a blanket of ice disrupted traffic and led to the closing of airports , schools and many businesses 如果这些天气预报是正确的，那将会是这个亚热带地区自97年的首个大规模冰暴气候，那个时候遍地的冰冻中断了交通，并使机场，学校以及许多商业场所关闭掉。
Leptospirosis is caused by bacteria of the genus leptospira . they may be free - living or associated with animal hosts and survive well in fresh water , soil , and mud in tropical areas . animal hosts include cattle , pigs , horses , dogs , rodents and wild animals 端螺旋体病由端螺旋体属细菌引起，它们可独立生存或寄居于动物宿主，包括牛猪马狗老鼠及野生动物，此外，端螺旋体亦常见于热带地区的水源土地及淤泥中。
Abstract : soil fertility of the plantations of paramichelia baillonii , betula alnoides , acacia mangium and altingia excelsa in tropical area of yunnan does not decline rapidly , and the physical and chemical properties of forestland are not affected greatly if the plantations can be managed properly 文摘:在云南热区营造山桂花、西南桦、马尖相思、高阿丁枫等4种人工林，只要经营得当，对林地土壤理化性质并不造成重大影响，不会引起地力迅速衰退。
They have different properties from montmorillonite and fe oxyhydroxides such as larger specific area , different surface potential , etc . under the acidity , temperature and other conditions ( initial arsenate concentration , ion strength , duration of adsorption ) simulated to that of soil in tropical and sub - tropical area , the adsorption of arsenate on the prepared fe - oxyhydroxide - montmorillonite complexes were conducted 在参考实际土壤ph值和离子强度的条件下，分别以ph值、砷初始浓度、离子强度、吸附时间、吸附温度为影响因素，进行了低聚合羟基铁?蒙脱石复合体、蒙脱石原样及水合氧化铁吸附砷酸根离子的对比实验；并用正交实验方法，进一步研究了上述因素对复合体砷吸附能力的相对影响程度。
