ISSN:
1572-9915
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Energy, Environment Protection, Nuclear Power Engineering
,
Ethnic Sciences
Notes:
Abstract The net primary production of the biosphere is about 160×10 9 tons/year, with 34% of this in marine, 0.8% in freshwater, and 66% in terrestrial ecosystems. World biomass (in the year 1950) is estimated as 1840×109 tons of dry matter, strongly concentrated on the continents (99.8%) and mostly in forests (90%). The total chlorophyll of the biosphere is about 240×106 tons; with about 90% of this on land. Land communities typically have 3–8 m2 of leaf surface and 1–4 g of chlorophyll per m2 of ground surface; chlorophyll in the oceans ranges mostly downward from 0.5 g/m2. Terrestrial and marine communities are in contrast in their mean ratios of biomass to net annual productivity (17.3 and 0.07) and of net annual productivity to chlorophyll (473 and 3100g/g). Man harvests about 1.3×109 tons/year of food from the land surface, about 17×106 tons/year from water bodies, with 88% of this from the seas. Despite the immensity of the biosphere, man has reduced its biomass and is beginning, with pollution, to affect its productivity. The relation of an exponentially increasing human population and industry to the biosphere is thus unstable. Some characteristics of this instability and the different consequences of overgrowth for poor or developing and rich or developed countries are considered.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01536732
