Encyclopedia of Global Resources part 16 provides a wide variety of perspectives on both traditional and more recent views of Earth's resources. It serves as a bridge connecting the domains of resource exploitation, environmentalism, geology, and biology, and it explains their interrelationships in terms that students and other nonspecialists can understand. The articles in this set are extremely diverse, with articles covering soil, fisheries, forests, aluminum, the Industrial Revolution, the . Department of the Interior, the hydrologic cycle, glass, and placer mineral deposits. . | 120 Biosphere Global Resources gradually blend into one another. The biome concept finds use in the biosphere reserve program which is based on environmental planning aimed at saving substantial portions of each unique biome. Energy Entering the Biosphere The biosphere concept ser ves an accounting function by placing all living systems on one enclosed spaceship Earth a concept that became far easier for the public to visualize when the space program provided actual photographs of Earth as a planet. It became obvious that energy input was limited and that nutrients must be recycled. The Earth intercepts about billion billion horsepower of energy per year as sunlight. Most reflects back into space or temporarily heats surfaces. Because photosynthetic leaves and algae intercept less than 1 percent of this light there is a limit on the amount of plant life that can be supported and on the amount of animal life and decomposers that can be fed. Ecologists have estimated that the maximum amount of living tissue both animals and plants that can be supported in the biosphere each year is about 370 billion metric tons consisting of about 260 billion metric tons of plants and 110 billion metric tons of consumers. Cycles in the Biosphere Water in the biosphere is stable at about billion cubic kilometers all but 3 percent of which is salt water in oceans. Three-quarters of fresh water has been estimated to be frozen in glaciers and polar ice caps. The Earth s water cycle hydrologic cycle then involves less than 1 percent of the total water which evaporates from ocean surfaces or transpires through plant leaves and then precipitates back down as rain snow and so on. While water is involved in the photosynthesis reaction water is far more important in plant transpiration where on average a hundred units of water must flow through a plant to produce one unit of plant tissue. More than any other factor the pace of the water cycle and the uneven distribution ofwater account
