问题 填空题 案例分析题

研究发现,每升天然水中含0.01毫克汞或者0.1毫克的杀虫剂,就会对人体造成危害。某研究小组开展了某湖泊中环境问题的研究,他们首先选取了该湖泊中5种不同的生物A、B、C、D、E,并对其进行消化道内食物组成的分析;然后又请当地湖泊研究所的专家对这5种生物体内2种污染物的含量进行了测定,如下表所示。分析回答:

 

分析上表,你认为这一湖泊面临的主要环境问题是什么?()。针对这一问题,你将提出什么样的保护或改善建议?()。

答案

参考答案:重金属离子和杀虫剂污染;防止重金属离子、杀虫剂等有害物质进入水体

解析:(1)从表中的统计可看出小球藻是生产者,被水蚤和河蚌所捕食,而水蚤又是鱼(乙)和河蚌的食物,鱼(乙)又被鱼(甲)所捕食,由此形成的食物链是:,河蚌(B)和水蚤(E)的关系是捕食和竞争。(2)从B出发,设当食物比例为C∶E=1∶1时,B的能量为x,需要的C为(1/2)x×10+(1/2)x×10×10=55x;设当食物比例调整为C∶E=2∶1时,B的能量为y,需要的C为(2/3)y×10+(1/3)y×10×10=40y,由于两种情况下,生产者的数量是一定的,所以55x=40y,则y=1.375x。(3)由图2可知甲是生产者、乙是消费者、丙是分解者、丁是无机环境;①是光合作用,②⑤⑥是呼吸作用,③是乙摄食甲,④⑦是分解者的分解作用。(4)从表中可以看出,该湖泊重金属离子和杀虫剂污染严重,应采取措施防止重金属离子、杀虫剂等有害物质进入水体。考点:本题考查种间关系、食物链和食物网、生态系统的成分、生态系统的能量流动和物质循环以及环境问题的知识。意在考查能理解所学知识的要点,把握知识间的内在联系,把握知识间的内在联系,能用文字、图表以及数学方式等多种表达形式准确地描述生物学方面的内容的能力

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Burkina Faso student teacher Hema Cecile has a lot more time to crack the books thanks to a recent initiative from the World Bank and the International Finance Corporation (IFC). The launch of the Lighting Africa program by the two organizations this year has made it possible for Cecile to swap kerosene lamps for a solar-powered LED lantern.

Lighting Africa is a $12 million project which intends to bring light to the poorest regions across sub-Saharan Africa. The program works with the lighting industry to develop clean, affordable lighting and energy solutions for millions without access to electric grids. Its aim is to accelerate the market and to develop education programs that inform off-grid populations currently dependent on costly, inefficient and hazardous fuel-based lighting about modern alternatives.

Cecile used to spend $3-4 a month on kerosene for her lamp. That is a large proportion of her earnings—like 70 percent of the population she lives on less than $2 a day. In the weeks since buying her lantern she has managed to read four books including Madame Bovary. by Gustave Flaubert and Emile Zola’s Germinal. She is among the most learned in a society which has the world’s lowest literacy rate, according to a 2007 UN Human Development Report. When she graduates next year she will teach in a local junior school She makes ends meet by holiday jobs as a cleaner and an IT trainer. To earn her daily ration of cornmeal she does shifts from May to September in a corn field.

The lanterns are designed to look like the kerosene ones they are replacing in order to increase adoption among the population. Each has a small solar panel on the top and costs an average $30, although some cost $100, depending on the size of the battery and the number of LED lights it contains.

Because of the large number of sunlight hours in Burkina Faso, the lamps can be relied on to work whenever needed. The battery life is 2-4 years, and can be replaced once they lose their storage capacity. The LED lights last 5-10 years.

Although it is barely out of its trial period the project, Chabanne said there are signs the project is a boon for the population in areas other than household savings and education. "There are fewer people reporting eye problems to the local hospital.

The word "swap" ( Line 4, Para. 1 ) most probably means ()

A. to exchange

B. to destroy

C. to invent

D. to copy