Within the development of the relationship of population, resource and environment, it is obvious to find …show more content…
Land is the material basis of human survival. In the demand of the food sources of the survival of human beings, crops cultivated land accounts for 88%, 10% of grasslands and pastoral areas and 2% counted for marine. With the development and utilization of ocean, energy applied by sea food for human beings will increase. At present, the cultivated land of the world is about 1.37 x 109 hm2, which shows per capital is about 0.26 hm2. But due to the increase of the non-agricultural land, land desertification, soil erosion, soil pollution and so on, it prompts the contradiction between population increase and reduce land resources becoming more and more sharp. What’s more, the pressure of increase in population on land is becoming bigger and bigger. According to the United Nations food and agriculture organization, nowadays, about 500 million people around the world are in a state of super land bearing capacity. Population overload on the ecological environment, especially the agricultural ecological environment is a real …show more content…
So the fresh water is going to run out. To discover and to make use of new sources are necessary within two aspects. One is to find fresh water resource which hasn 't been found or used. The other way is to thoroughly look for fresh water from where other than the fresh water resource it self. This is mainly asked to turn which is not fresh water purification into fresh water. Since sea water accounts a lot of the total water resources of the earth. The key means to turn them into the water we can drink is to purify and desalinate. Although it is not because that there is no water desalination plant in the world, why we still worry about water resources drying up? That is mainly due to the desalination technology which is not very mature and completed. Not to mention, the cost is very high as well. Ordinary people can not afford such high price. That explains why this technique is not popularized worldwide, but most concentrated in the developed countries. That is to say, if we want to fade in seawater batches, the most important is to rely on science technology to improve the efficiency of desalination, reduce the desalination cost and let ordinary people be able to use the desalinate water under a proper price. Besides, there is still a solution which is to improve technical level to make full use of polar glaciers storing a large amount of fresh water resources. This is what can be considered later. At the same time, we can not ignore that to improve the