Hydrological conditions in many Louisiana baldcypress swamps are changing because of river flow regulation, channelization, and manipulation of sediment. How is this management affecting productivity of the forest? Do changes in plant communities in turn affect hydrology of the wetland?

Caddo Lake, Texas/Louisiana

► Microtopography determines site suitability. Productivity is greater in shallow water (right background) than in deep water (left) where trees, though more than 100 years older, are much smaller. Deep water is a stressor that reduces vigor.

Atchafalaya River swamp, Louisiana

► Dying old-growth baldcypress are tangible examples of how changing site conditions affect ecosystems.

Baldcypress tree rings

► Dendrochronology and dendrochemistry are tools to unravel the complex relationship between site and forest growth.

Wetlands perform important functions in river hydrology, water quality, while also supporting important ecosystems. River management affects these processes by changing the rate and magnitude of water and nutrient exchanges between river channels and adjacent wetlands. It is important to develop tools that allow us to predict how changing management will affect the connections between wetlands and rivers.

Lafourche Parish, Louisiana

► River water dominates off-channel wetlands during overbank flow, but are subsurface connections to groundwater important for water quality and aquatic ecosystems when river levels are lower?

Pearl River, Louisiana/Mississippi

► Seasonally flooded bottomland hardwoods are regionally important wetlands. Flooding frequency and depth control, for example, site productivity, nutrient cycling, and plant species.