Geoscience Reference
In-Depth Information
illustrated how people became involved in one way or another as participants in the
research teams or as residents in the study sites. Their learning from each other and
their sharing information and ideas, especially with diverse students, were critical
given that there was little previous information on which to build in these early
studies. Many of these programs that began decades ago are still working on new
Box 29.1. Luquillo, Puerto Rico
One of the fi rst large-scale tropical ecosystem research projects was located in
the Luquillo Mountains of Puerto Rico, where Golley collaborated with a
group of ecologists organized by H.T. Odum in the early 1960s. The project
followed an earlier study funded by the Rockefeller Foundation with a focus
on large-scale measures of metabolism of mangrove forest and the rain forest
(Golley et al.
1962
; Odum and Jordan
1970
; Lugo
2004
). With a goal of
understanding the functioning of rainforest ecosystems, a large clear-plastic
cylinder was built to enclose a stand of trees. Oxygen production and con-
sumption were measured to track day and night metabolism and transpiration
(Jordan
2001
; Lugo
2004
). Solar energy, rainfall, temperature, and soil nutri-
ents were measured to determine variations over time in the total metabolism
of the soil and the forest trees.
The project was part of a response to international concern about the safe
development of nuclear power and its peaceful applications (Creager
2013
).
A main objective of the El Verde research was to measure the effects of a brief
release of gamma ray radiation from a cesium-137 source on a small area of
the Luquillo Experimental Forest (now also known as the El Yunque National
Forest), part of the US National Forests. The US Atomic Energy Commission
supported this study of an “acute exposure” (that might occur from an acci-
dental release of radiation from a power plant) to compare effects with a slow,
“chronic release” of cesium-137 in a temperate forest on Long Island,
New York at the Brookhaven National Laboratory (Woodwell
1962
), and
related studies at Oak Ridge, Tennessee (Creager
2013
). Beginning in 1960,
research in Puerto Rico included collections of leaf litter and fauna before and
after the radiation release, to quantify how the biota (encompassing a high
diversity of trees) might differ in daily and monthly leaf-fall rates. These data
on primary productivity allowed for a wide range of comparisons with other
tropical forests (Jordan
1983
; Lugo and Heartsill-Scalley
2014
).
Additional collections of leaf litter, gas exchange measurements, and studies
on the diversity the biota continue as part the US National Science Foundation's
Long-Term Ecological Research Program. The early baseline data remain use-
ful several decades later (Harris et al.
2012
; Lugo and Heartsill-Scalley
2014
).
Current studies focus on the long-term effects of variable rainfall and the effects
of changes in the frequency of hurricanes and droughts (Brokaw et al.
2012
;
(continued)
Search WWH ::
Custom Search