The impact of weather, sea action, and human action on Louisiana's coastal wetlands has become more than a theoretical problem since the recent hurricanes. Coastal erosion of wetlands along the Gulf Coast is at least one factor involved in the current plight of New Orleans and other portions of the metropolitan region along the Mississippi River and Lake Pontchartrain.

At the Louisiana Natural Resources Symposium sponsored by the LSU AgCenter in Baton Rouge earlier this year, a report on a special Science Working Group commissioned by Governor Kathleen Babineaux outlined the status of coastal wetlands, and the impact of forestry and other activities.

Following is a portion of the report, detailing research on the coastal forests and other factors affecting the coastal region.

The Futrure of Our Coastal Wetlands Forests

The continued existence of coastal cypress-tupelo forest depends on replacement of trees following disturbance, especially the replacement following logging or other disturbances such as tropical storms and hurricanes.

A number of studies (DeBell and Naylor 1972, Hook 1984, Kozlowski 1997) have shown that bald cypress and water tupelo swamps must have dry periods for the seed to germinate and establish. Coppice reproduction of bald cypress is possible, but current data indicate that in many cases, the majority of sprouts die within several years and thus do not contribute as a reliable means of regeneration (Kennedy 1982, Conner et al. 1986, Conner 1988, Conner and Toliver 1990, Ewel 1996, Keim et al. 2005).

If water levels continue to rise, death of trees and failure of regeneration and establishment within coastal forest areas will eventually lead to replacement by scrub-shrub stands, marsh, or open water.

Even with current restoration efforts, the area of swamps in Louisiana's Deltaic Plain is projected to decrease by 93,845 hectares by the year 2050. This represents 27% of the existing wetland forest in the Deltaic Plain and, in other areas, three of the nine basins will lose from 30% to 55% of their remaining swamps. Adding sediments and nutrients to these degraded coastal wetland forests is an essential component of sustaining the coastal wetland forest ecosystem (Day et al. 1999,2000,2003, Woods, 2004).

Continued water level rise will subject coastal forests to more prolonged and deeper flood events. Even though many of the forest species growing in these areas are adapted to prolonged inundation, extended flooding during the growing season can cause mortality and loss of productivity of these tree species (Mitsch & Ewel 1979, Conner & Brody 1989, Conner & Day 1992, Megonigal et a1. 1997, Pezeshki et al. 1990, Young et al. 1995).

Many of the trees in these areas are showing evidence of severe stress (Hoeppner 2002, Shaffer et al. 2003, Conner et al. 1993). Even bald cypress and water tupelo, two of the dominant species In Louisiana's coastal forests, can slowly die when exposed to prolonged, deep water flooding of longer than normal duration. Impoundments have been shown to have detrimental effects on adult trees through reduced growth, crown dieback, increased susceptibility to insects and pathogens, decreased root mass and increased tree mortality (Conner et al. 1981, King 1995, Keeland et al. 1997).

The hydrologic changes produced by impoundment are rapid in comparison to those caused by subsidence and sea-level rise, and effects on forest productivity and turnover rates may differ between natural sites and artificial impoundments. With increased subsidence and sea-level rise, saltwater intrusion into coastal wetland forests reduces productivity and can kill bald cypress and water tupelo (Allen 1992, Krauss et al. 2000, Pezeshki et al. 1990).

Bald cypress appears to tolerate salinity up to 8 ppt, but productivity and survival decline 1" with salinity above 4 ppt (Pezeshki et al. 1990, Conner and Askew 1992, Conner 1994, Pezeshki et al. 1995, Allen et al. 1996, Conner and Ozalp 2002). Also of critical importance is the fact that these permanently flooded forests fail to regenerate and become established when trees are removed either by logging or natural disturbance.

Together, these impacts are so substantial that loss of coastal wetland forests is nearly assured in some areas of coastal Louisiana without active measures to ameliorate problems.

Regeneration is a critical process of specific concern in maintaining coastal wetland forest resources. Successful natural regeneration of this resource in the 1920s and 1930s was caused by fortuitous conditions existing at that time. Bald cypress seeds cannot germinate in standing water, and seedlings must grow tall enough during short drawdown periods for their crowns to extend above the water surface to survive flooding during the growing season. Bald cypress seedlings can withstand complete inundation for up to 45 days, but long-term flooding above the foliage results in high mortality. Bald cypress is exacting in its needs, but regenerates well in swamps where there is ample sunlight and the seedbed is moist but not flooded during the period of seed germination and seedling establishment. Currently, there is a lack of regeneration in coastal cypress-tupelo forests that is a direct result of factors identified in this paper and their interactions with regeneration processes.

Since regeneration is a critical key to coastal forest protection and conservation, the SWG developed a set of regeneration condition classes for the dominant wetland forest type, Louisiana's coastal cypress-tupelo forests.

Basically, Condition Class I includes 1. seasonally flooded forests with a pulsing of fresh water and sufficient flood free period that natural regeneration can establish a new forest stand.

Condition Class II has standing water for such a long period each year that natural regeneration is unlikely to succeed, but water levels of 120 cm or less make artificial regeneration feasible.

Finally, Condition Class III includes either forests that are flooded deeper than 120 cm on a permanent basis or those sites affected by salinity levels that make even artificial regeneration improbable or impractical. Development of methods of analyzing sites for, these attributes will allow recommendations regarding regeneration where possible.

Those forests in Condition Class III must have a restored hydrological regime before they can be regenerated in a practical way. Therefore, these forest stands should not be harvested under the current set of conditions.

WHAT CAN BE DONE TO CONSERVE AND PROTECT LOUISIANA'S COASTAL WETLAND FORESTS?

• What the State Can Do

The SWG on Coastal Wetland Forest Conservation and Use made recommendations to the Governor's Office regarding actions that the state could take to conserve and protect these forests. For details on the recommendations by the SWG, see the report at 126.

In general terms, the SWG recommended the following:

Place priority on conserving, restoring, and managing these coastal wetland forests.

Recognize the set of condition classes that the SWG outlined relative to regeneration ability of specific sites.

Place priority on maintaining the hydrological regime of the most productive sites and avoid loss of the more sensitive sites, including placement of a delay in harvesting those not likely to regenerate until conditions are changed.

Help to ensure proper management and regeneration through recommendations on written forest management plans with specifics on regeneration.

Develop spatially explicit database and long-term monitoring efforts with regular updating to guide management.

Recognize an expanded area of coastal forests.

Ensure that all agencies and organizations share and coordinate information, develop practices to prevent coastal forest loss, and actively pursue restoration of degraded forests.

Enhance ecosystem functions through hydrological management decisions related to construction and other activities in wetland areas.

• What Professional Foresters Can Do

It is the inherent responsibility of all professional foresters to ensure forest sustainability and strive to meet the landowner's objectives. Professional foresters can do much to conserve and protect Louisiana's coastal wetland forests and act in the long-term best interest of landowners, including the following:

Recommend harvesting of healthy forest areas only when the forest stand can readily be regenerated, leading to long-term establishment of stands that will maintain sustainable productivity into the next generation of forests.

Create written forest management plans that are explicit about how management will be sustainable and how regeneration and long-term wetland forest establishment Will be guaranteed.

Indicate what necessary and feasible alterations to site hydrological regime may help ensure future productivity .

Explore alternative revenues or management options for sites not likely to regenerate and become established.

Work with scientists to develop more reliable regeneration for a range of difficult site conditions.

Look to see how the Sustainable Forestry Initiative can help protect and conserve these forests for the landowners and future generations.

• What Research Scientists Can Do

Research in Louisiana's coastal forest has not kept pace with past problems, much less those that are now upon us. Part of the reason is that we have not always appreciated their importance to our coast and have not understood the many functions and services they provide. We are only now beginning to see the worth of coastal wetland forests and will continue to increase our understanding of their values and importance through new and expanding research. Detailed numbers of coastal wetland forest acreage and the condition of these forests are still not available. Some coastal forests are rapidly disappearing, and many others are degrading. We know that some cannot regenerate and become established, if harvested. Research scientists t can assist in ensuring the future of these forests in a number ofways, by:

Continuing to reveal and interpret the data that exists-

Establishing new research related to the effects of hydrologic regime and soils on the growth and productivity of these forests, both young and old.

Establishing research to provide better information on seedling and coppice regeneration and stand establishment under a variety of site conditions and harvesting regimes; This research may also help establish new methods of regeneration for difficult sites.

Discerning new methods of evaluating and mapping condition classes and forest health both on the ground and by remote sensing techniques-

Evaluating what the public knows and how much they are interested in conserving and protecting these forests.

Conducting additional research in coastal forests to understand the important links to other functions and services that are crucial to wildlife, fisheries, clean water, and coastal processes.

Investigate conservation alternatives acceptable to forest landowners, including set-asides, easements, and sale of timber rights.

• What Coastal Forest Landowners Can Do

Perhaps the most important and crucial key to protecting, conserving, and continuing to use Louisiana's coastal wetland forests lies with the landowners and their families.

They have a great personal connection to these lands, and they hold the public's many values of these lands in their hands. Coastal forest landowners can do much to see that these lands are protected and conserved through the following actions:

Recognize the serious nature of the problem.

Work to ensure that proper forest management techniques are used on lands that can be regenerated on a sustainable basis and that regeneration occurs;

ApplIcatIon of BMPs (Best Management Practices) assists in reducIng non-point source sediment to waterways but has little to do with proper stand management and regeneration at this time.

Demand to know the correct state of their lands and the condition they are in relative to regeneration, if harvested.

On hydrologically degraded lands, work with the state and others to further efforts to restore them, so as to regain productivity .

Be willing, when necessary , to temporarily forgo timber harvesting on those portions of their land that will not regenerate and become established under current conditions.

Insist that professional foresters provide a written management plan that details how the lands will be regenerated after harvest and how a new forest of equal or better productivity will be established; Get a second independent opinion when lands are frequently flooded for long periods, especially during the growing season; Stump sprouting is not a reliable means of regeneration for bald cypress or tupelo.

Provide research scientists with information on how the flood frequency, flood depth, and forest conditions have changed over time and allow them access to land for research on this problem.

Look for alternative income sources (instead of timber harvests in coastal forests). Often, other sources of income can be steadier and offer a way to keep the trees, while enjoying an income and the other benefits forests provide.

Consider placing your lands in a "forest reserve" system or some other category of compensation, if developed by the State.

Consider donating your land to a conservation organization that will provide protection and allow you to reap tax benefits.

Contact your local Cooperative Extension Service county/Parish agent for 1 educational materials and programs.

What Everyone Can Do

Recognize the serious nature of the problem with Louisiana's coastal wetland forests.

Contact federal and state senators and representatives, as well as local officials about helping to save existing and restore degraded coastal wetland forests in Louisiana.

Recognize that we can continue to conserve and protect these resources only for those coastal forests that are sustainable.

Voice your support for efforts to conserve and protect these forests in surveys of opinion and to the news media, friends, and those at work.

SUMMARY AND CONCLUSIONS

The functions and ecosystem services of Louisiana's coastal wetland forests are threatened by both large- and small-scale hydrologic and geomorphic alterations and by conversion of these forests to other uses. Over the last hundred years, Louisiana has lost a considerable amount of coastal forest and the current condition of many remaining forests is not good. Sustainability has been compromised in large part by man-made alterations to the landscape and the natural processes that result. Once flood pulsing from leveed rivers was stopped, sediments and nutrients were excluded from associated coastal Iwetland forests and the conditions necessary for sustaining forests were disrupted. In some areas, land subsidence and altered hydrological regime have caused permanent or near permanent flooding that prevents forest regeneration and establishment. To ensure the sustainability of Louisiana's coastal wetland forest it is time to take action. The Governor's Science Working Group has made recommendations to ensure the sustainability of Louisiana's coastal wetland forests. An Advisory Panel to the Science Working Group was also established by the Governor's office. This panel is composed of a diverse group consisting of federal agency, state agency, non-governmental organizations, and landowners. The Advisory Panel will also provide input to the Governor's office relative to the Science Working Group's recommendations. There are many things that various groups and the general public can do to hep ensure the siustainability pof these forests. It is the hope of the authors and many others that everyone will get involved in the protection and conservation of this valuable forest ecosystem.

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