Land-use history and the or igins and effects of lianas on tree-communities. The case of secondary forests in Northeastern Yucatan Peninsula, Mexico

Abstract:

Abstract: Economic problems generate large secondary tropical forests due to crop abandonment; lianas (woody vines climbing upon trees) proliferate there. Lianas generally retard the growth and carbon capture of trees , potentially enhancing global change. It is not known whether all liana species play such a role and which land-use disturbances determined the current species composition of liana communities. We surveyed all lianas ≥1 cm diameter at ground level and all trees ≥3.16 cm diameter at 1.3 m above ground in twelve plots 20 × 20-m each in semi-evergreen tropical forests in Northeastern Yucatan Peninsula, Mexico, re-measuring the trees 15 mo later. Lianas were classified into two anatomic types: "hard " (typical stem with compact xylem masses) and "soft" (with much parenchyma and wide xylem vessels). History, archaeology, anthropology, and remote sensing studies, as well as non-formal interviews were used to determine the land-use history y of each stand. Increasing densities of the hard liana Dalbergia glabra (Leguminosae), but not of soft lianas - Arrabidaea spp, Cydista sp, MellIoaspp (Bignoniaceae) and Serjania sp (Sapindaceae), were related to more rapid relative growth rates of trees (Linear regression, R2 = 0.680, P = 0.001). Where D. glabra dominated, the trees hosting it grew more rapidly, but trees with large liana-tangles grew more slowly where soft lianas were dominant (Kruskall Wallis, P > 0.01 in both cases). The anatomy of soft lianas suggests that they are less able to survive burn after slash during shifting cultivation than D. glabra - the previous land use where D. glabra dominated. Soft-liana dominated stands were not burnt but subjected to liana-cut during logging and extraction of lianas, palm leaves and latex from Manilkara %apota trees. Our results suggest that some lianas enhance carbon capture mitigating global change, whereas others do not and that the dominance of one liana species is a legacy of previous land use, which is better understood by combining natural and social sciences.

Año de publicación:

2009

Keywords:

• Lianas
• Secondary forest
• Burn
• tree growth
• Yucatán
• Relative abundance
• Slash
• Injury-recovery

Fuente:

scopus