ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
ILLUSTRATED FLORA OF EAST TEXAS - Brit - Botanical Research ...
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ORIGIN AND DIVERSITY <strong>OF</strong> <strong>EAST</strong> <strong>TEXAS</strong> <strong>FLORA</strong>/INTRODUCTION 199<br />
presents both an unparalleled conservation opportunity and the potential for widespread<br />
loss of forest land through various types of development. As a result of these concerns, the<br />
National Parks Conservation Association recently named the Big Thicket National Preserve<br />
as one of its “Ten Most Endangered Parks” (National Parks Conservation Association 2003;<br />
Warchut 2003).<br />
A longer-term concern is the effect rising atmospheric CO2 levels and possible global<br />
climate change will have on the Big Thicket and its species. The local consequences of such<br />
climate change are particularly difficult to predict, but the Big Thicket and East Texas as a<br />
whole could see substantial effects. As noted by Cameron et al. (1997), the boundaries of<br />
the Big Thicket National Preserve are static, while many of the habitats and species being<br />
protected may face significant shifts in their ranges in response to climate change (e.g.,<br />
northern movement of climatic zones). In an area such as the Big Thicket, where most areas<br />
outside the Preserve have been highly modified by human activities, the ability of species to<br />
move and thus survive changes in climate is highly limited. Emphasizing this point,<br />
Cameron et al. (1997) noted that while global climate change “is a serious threat to the<br />
integrity of all natural systems and nature preserves, natural habitats in east Texas along with<br />
their associated fauna are particularly vulnerable to environmental change because of their<br />
extreme fragmentation.…”<br />
Faced with these challenges, conservationists are actively working in a variety of ways.<br />
Numerous individuals, both inside and outside of government, are involved in efforts to<br />
secure the remainder of the funding for the previously approved “additions” to the national<br />
preserve. Because of the large amount of timber company land now for sale, efforts are being<br />
made at this critical juncture to purchase some of the available acreage to increase the area<br />
permanently protected. For example, organizations such as the Conservation Fund are<br />
attempting to buy areas adjacent to the preserve, including a 1,000 acre (405 hectare) plot<br />
which will provide a buffer zone around the new visitor center. The Big Thicket Association<br />
(www.btatx.org) still actively engages in conservation activities, including publication of the<br />
Big Thicket Reporter (through which information on preservation and related efforts can be<br />
obtained), co-hosting Big Thicket Science Conferences, and supporting efforts to expand the<br />
national preserve. Numerous other organizations and individuals are involved in various<br />
activities to focus attention on the preserve and the larger ecosystem, with the goal ultimately<br />
being to protect the Big Thicket. These activities range from creating and managing small preserves<br />
(e.g., Watson Pineland Preserve), to research (e.g., Paul Harcombe), writing and publishing<br />
(e.g., James Cozine, Pete Gunter, Maxine Johnston), fund-raising, and political action—all<br />
are important. One specific example is Lamar University’s Center for the Study of the Big<br />
Thicket (http://dept.lamar.edu/artssciences/BIGTHICKET/home.htm), which is promoting<br />
the study of the natural and cultural history of the Big Thicket.<br />
Such varied conservation approaches are essential, since what is done now and in the<br />
next few years will forever determine the fate of the ecosystem, and future generations will<br />
look back to this time as a turning point in efforts to save the Big Thicket of East Texas.<br />
ORIGIN AND DIVERSITY <strong>OF</strong> THE <strong>EAST</strong> <strong>TEXAS</strong> <strong>FLORA</strong><br />
INTRODUCTION TO THE <strong>EAST</strong> <strong>TEXAS</strong> <strong>FLORA</strong><br />
The flora of East Texas, like that of any relatively large region, has a complex and varied origin.<br />
Ultimately, it is the result of the evolutionary and distributional history of each of the component<br />
species, as well as a reflection of past and present climate and soil conditions.<br />
However, several influences can be observed which together allow at least a broad understanding<br />
of how the present flora originated. East Texas contains components of four major<br />
floristic provinces as defined by Thorne (1993d): the Appalachian Province, the Atlantic and<br />
Gulf Coastal Plain Province, the North American Prairies Province, and the Sonoran Province.