生物生产量的研究是六十年代以来兴起的一个崭新领域,它以有机物的重量或能量为指标,研究各种生态系统中物质与能量的数量及其固定、消耗、分配、积累与转化的特点,并探讨其与生态因素间的相互关系,制定生物生产力的数学模型,为合理保护、管理和开发利用生物资源,创造稳产高产的生态系统提供理论依据。随着生产的发展和对自然资源开发利用的需要,生物生产量的研究已愈来愈引起人们的关注,不但成为当代生物学研究的中心问题之一,而且对其他学科的发展亦产生重大影响。

During 1963-1972, a large-scale "International Biology Plan" was led and organized by UNESCO. Quite a few countries and a great number of scientists took part in the plan. The plan accumulated many data about primary biological production in the different regions of the world. But it also costs a great deal of time and money. Therefore, several scientists started to set up various models to calculate the biological productivity and to draw up biological productivity maps. The Miami Model is one of them.The Miami Model consists of two formulas that described a large number of mutual relationships between the real survey value of biological productivity and the local average temperature and average rainfall of different zones on the earth. The two formulas are:where: y1 = Primary biological productivity according to temperature (g/m2/year); y2 = Primary biological productivity according to rainfall (g/m2/year); t = Local annual average temperature (°G); p = Local annual average rainfall (mm); and e = The base of natural logarithm.Finally, according to Liebig's restrictive factor law, the local productivity is either y1 or y2 whichever is smaller. We collected some 600 meteorological data, and culcalated them using Miami Model, and then, drew up" Miami Model Productivity Map (Isogram) in China".Due to the map, the total primary biological productivity in China is 8.27×109t per year. It is 6.64% of the total world's primary productivity (124.5 X 10't per year). China's per km2 productivity is 861.45t per year which is equal to the world's level. China's per capita productivity is 8.14t per year which is only one-third of world's average (28.55 t per year).