International Energy Agency (IEA) Task 40. Sustainable International Bioenergy Trade: Securing Supply and Demand. Country Report-United States

摘要

The United States population as of August 2008 was 304,967,620, and the gross domestic product (GDP) was $14,256.5 billion (2008 dollars). The United States has a total land area of nearly 2.3 billion acres with an approximate breakdown of land use as follows: Forest land, 651 million acres (28.8%); Grassland pasture and range land, 587 million acres (25.9%); Crop land, 442 million acres (19.5%); Special uses (primarily parks and wildlife areas), 297 million acres (13.1%); Miscellaneous other uses, 228 million acres (10.1%) and Urban land, 60 million acres (2.6%). The most consistent trends in major uses of land (1945 to 2002) have been upwards in special-use and urban areas and downwards in total grazing lands. Forest-use area generally declined from 1949 to 1997 but increased by about 1% from 1997 to 2002. Total cropland area has declined over this 57-year period, but it has not done so consistently. Total cropland area increased in the late 1940s, declined from 1949 to 1964, increased from 1964 to 1978, and then declined again from 1978 to 2002.