Environmental Engineering Reference
In-Depth Information
covered by lush vegetation and leaf litter. When a rain forest loses its trees, the soil is exposed to direct sun-
light and dries out. With vegetation gone, roots and leaf litter are not available to hold the soil in place. This
starts the process of desertification.
Rangeland Management
Grazing of cattle on rangeland can be sustainable when managed properly. Historically, in the United States,
public lands have been open to grazing, and ranchers have been paid subsidies for their cattle to graze lands, so
there has been little motivation to conserve. Now range managers control the use of rangeland by rotating use
and continually monitoring carrying capacity of the land. This, combined with the creation of overgrazing laws
and the efforts of ranchers to compromise with concerned parties, has led to more sustainable use of rangeland.
Internationally, the issue of overgrazing is even more dramatic, due to issues such as lack of available land. A
variety of initiatives are used to support better land-use practices globally. For example, the Farmer-Centered
Agricultural Resource Management Program (FARM) run by the United Nations helps farmers in eight Asian
countries use proven sustainable farming practices. Also, in China the Farmland Protection Law (1994) man-
dates that businesses building on farmland create equal farmland in another area.
Conservation-Related Laws
Because of the serious soil depletion and erosion issues the United States has faced, laws have been enac-
ted to protect this precious resource. In 1935, in response to the Dust Bowl, Congress enacted the Soil
Conservation Act, which established the Soil Conservation Service to monitor soil erosion. Now called the
Natural Resources Conservation Service, the agency has expanded to include water quality and pollution
control.
Other conservation-related acts include the Food Security Act (1985), the Conservation Reserve Program
(1985), the Taylor Grazing Act (1934), the National Environmental Policy Act (1969), the Endangered
Species Act (1973), the Federal Land Policy and Management Act (1976), the Public Rangelands Im-
provement Act (1978), and the Federal Agriculture Improvement and Reform Act (1996). For more in-
formation about U.S. laws, please refer to Appendix D.
Other Land Use
While much human land use involves extracting resources, ecosystems are impacted by other human actions as
well. The resources we harvest are used to develop and build products in a process that uses space, consumes
resources, and creates waste. Increasingly, modern humans are exploring ways to do so sustainably.
Urban Land Development
As human society has shifted from a rural, agricultural society to an urban, industrialized society, land use has
changed. Industrialization centralized many new jobs in urban areas, and since technological advancements
also made agricultural processes more efficient, fewer people were needed to produce the needed food. This
movement of people from rural to urban lifestyles is termed
urbanization.
Increased manufacturing and the associated developments in technology, along with increasing population
density in urban centers, have had both positive and negative consequences for the environment.
Advantages and Disadvantages of Urbanization
