What Is The Condition of California Wetlands?
Knowing how many wetlands we have is critical, but it is not the entire story. Effective protection and management decisions also require that we know something about the condition, or health, of wetlands. A healthy wetland can be defined as one that provides the needed levels of natural functions, goods, and services. The biological diversity of a wetland (number of species present) is often considered a proxy for its ability to persist over time, and can be used as another measure of health.
Poor wetland health is typically the result of human stressors, such as changes to water inputs, introduction of invasive species, pollution, climate change, or fragmentation. In particular, slight changes to water inputs can have large impacts on wetlands, particularly on seasonal wetlands that depend heavily on the arrival of seasonal water flows. Water inputs can change as a result of reservoirs, diversions, and levees, groundwater pumping and irrigation activities, and through altered climate regimes in the future.