Ecosystems
a species that spreads rapidly across large areas and causes harm
invasive species
ecological succession occurring on surfaces with bare rock and no soil
primary succession
a resource that a population cannot live without and that occurs in quantities lower than the population would require to increase in size
limiting resource
an area below the ocean where tectonic plates move away from each other
divergent boundary
a method of harvesting trees that involves removing all or almost all of the tree within an area
clear-cutting
a warm and wet biome found between 20 degree N and 20 degree S of the equator, with little seasonal temperature variation and high precipitation
tropical rainforest
the study of how species are distributed and interacting on islands
island biogeography
a factor that influences an individual's probability of survival and reproduction in a manner that depends on the size of the population
density-dependent factor
permeability
a shift in agricultural practices in the 20th century that included new management techniques and mechanization, as well as the triad of fertilization, irrigation, and improved crop varietes, that resulted in increased food output
the upper layer of ocean water in the ocean that receives enough sunlight for photosynthesis
photic zone
the number of species in a region or in a particular ecosystem
species diversity
an estimate of the average number of children that each woman in a population will bear throughout her childbearing year
total fertility rate
A horizon (topsoil)
an agricultural practice that uses a variety of techniques to minimize pesticide inputs
integrated pest management
the energy captured by producers in an ecosystem minus the energy producers respire
net primary productivity
the rate at which an ecosystem returns to its original state after a disruption
resilience
the number of years it takes a population to double
doubling time
the percentage of incoming sunlight reflected form a surface
albedo
plowing and harvesting parallel to the topographic contours of the land
contour plowing
fungi and bacteria that complete the breakdown process by converting organic matter into small elements and molecules that can be recycled back into the ecosystem
a species that is not very abundant but has large effects on an ecological community
keystone species
a theory that states that a country moves from high to lower birth and death rates as development occurs and that country moves from a preindustrial to an industrialized economic system
theory of demographic transition
a convection current in the atmosphere that lies between Hadley cells and polar cells
Ferrell cell
when a fire is deliberately set under controlled conditions, thereby decreasing the accumulation of dead biomass on the forest floor
prescribed burn