Restoration and Mycorrhizae
in Seasonal Tropical Forest in Mexico
Edith Allen
UC Riverside
Dept. of Botany & Plant Sci.
Riverside CA 92521-0124 USA
tel: (909) 787-2123
fax: (909) 787-4437
email: edith.allen@ucr.edu
UC Riverside
Dept. of Botany and Plant Sciences
Riverside CA 92521 USA
tel: (909) 787-4686
fax: (909) 787-4748
email: floramex@ucrac1.ucr.edu
and
San Diego State University
Dept. of Biology & Systems Ecology Group
San Diego CA 92182 USA
The proposed research combines two areas
of research, mycorrhizae and restoration ecology, that have special relevance
to the tropics. The dry seasonal tropical forests have received less attention
than the humid tropical forests, but they have been destroyed at a greater
rate.
 
Less than 10 percent of the Mesoamerican
seasonal tropical forest remains, so restoration must supplement conservation
for the protection of diversity and ecosystem functioning. We propose
to set up forest restoration research plots at two seasonal tropical
sites in Mexico, one on the central west coast at the Chamela Ecological
Reserve and one on the east coast at the El Eden Ecological Reserve
in northern Quintana Roo.
 Many
of the Pacific Coast forests have been converted to pasture, and the
remaining Quintana Roo forests are subject to hurricanes and frequent fires. Pteridium aquilinum (bracken
fern) has been invading the burned sites and slowing the time for natural
succession. The sites have many plant species and genera in common and
a similar seasonal dry climate, but have very different
soils.
 The Yucatan Peninsula
has calcareous, phosphorus-fixing
soils, while the Chamela area has geologically young soils with high
available P. This suggests that mycorrhizae may be more important for
P nutrition at El Eden than Chamela. Our preliminary surveys show that
the bracken fern fields have very low mycorrhizal activity immediately
after a fire, and Chamela pastures have changed species composition
of mycorrhizal fungi.
Thus we propose to examine the role of mycorrhizal inoculation
and tree planting on succession during three years. Our field experiments
will be replicated at both reserves, with 10 tree species from each
reserve planted into fields that have been experimentally burned. Different
sources of inoculum will be used, including forest, field, and commercial
inoculum, as well as an noninoculated control.
A greenhouse experiment will be done at the Chamela Reserve using local seeds and soil from both reserves
in pots inoculated with the same mycorrhizal treatments as in the field.
We will monitor naturally occurring species of mycorrhizal fungi and
root infection in different disturbance types at each reserve, mycorrhizal
and plant recolonization into the restored and control plots, and measures
of soil nutrient pools and turnover of N over time.
In addition, we will study tree growth
and succession after anthropogenic disturbance, both of which are little
understood for these forests.
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