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选取我国东北、西南、西北及中北部地区的10个典型湖泊,调查了表层沉积物生物硅含量变化情况,并通过区域对比分析了生物硅含量变化的原因,寻找我国湖泊生物硅变化的空间规律。结果表明,西北及中北部地区湖泊生物硅含量平均值整体低于东北和西南地区湖泊,可能是由于西北及中北部地区较低的温度和较少的降水量导致硅藻生长受限,从而造成生物硅含量偏低。东北湖泊与西南湖泊生物硅含量相对较高,但其形成原因不同。东北2个湖泊均靠近人类聚居区,属富营养型湖泊,虽然东北地区年均温较低,但充足的营养盐为硅藻生长提供了必要因素。而西南地区湖泊大多为中贫营养型湖泊,其生物硅含量整体较高可能主要归因于较高的温度和较多的降水。
Ten typical lakes in northeastern, southwestern, northwestern and central-northern regions of China were selected to investigate the changes of biosilica content in surface sediments. The reasons for the changes in biosilica content were analyzed by regional comparison and the spatial rules of bio-silicon changes in lakes in China . The results showed that the mean values of bio-silica in lakes in the northwest and central-north regions were lower than those in northeastern and southwestern regions, possibly due to the limited growth of diatoms due to the lower temperature and less precipitation in the northwest and central-north regions Low biological silicon content. The biogenic silicon content in northeast lakes and southwestern lakes is relatively high, but their formation causes are different. The two lakes in northeast China are close to the human settlements and belong to the eutrophic lakes. Although the average annual temperature is relatively low in the northeast, adequate nutrients provide the necessary factors for the growth of diatoms. Most lakes in Southwest China are poor and nutrient-poor lakes. The high overall biosilica content may be mainly due to the higher temperature and more precipitation.