Research History and Opportunities in the Luquillo Experimental Forest

Spatial and seasonal dynamics of surface soil carbon in the Luquillo Experimental Forest, Puerto Rico

“…Nevertheless, the moderate correlation between simulated and observed SOC (R 2 =0.71) indicated that our spatial version of the CENTURY model was capable of capturing the essential geographic and topographic variability in SOC storage and fluxes within the LEF. The lower simulation accuracy for the Tabonuco forest compared to the Colorado, Palm and Elfin forests is probably the results of more heterogeneous pattern of soil physical and chemical properties resulting from past human disturbances (deforestation, agriculture and other activities) that were much more prevalent at low elevations than at higher elevations (Brown et al 1983; Relationship between elevation and simulated soil moisture index, defined here as the ratio of rainfall plus soil available water to potential evapotranspiration (PET) in December in the Luquillo Experimental Forest (LEF), Puerto Rico. At a given elevation, variation in SMI is due to variation in topographic features: valleys tend to have higher SMI values than ridges especially for palm forest between 500 and 800 m. Scatena and Lugo, 1995).…”

“…Mountains in the LEF are characterized by steep, highly dissected topography with slopes varying between 2 and 75°(22°on average) and they contain geomorphologically complex combinations of ridge, slope, upland valley and riparian valley (Garcia-Montiel and Scatena, 1994;Scatena and Lugo, 1995). Soils within the LEF are derived from the volcanoclastic sediments and are taxonomically diverse (Brown et al, 1983;Silver et al, 1999).…”

“…In the LEF, necromass turnover time was available only for the Tabonuco forest (9350 days). We assigned this turnover rate to the slow carbon pool, and assigned turnover rates to the active and passive pools by multiplying this rate by the relative proportion of the base settings of the CENTURY model (Brown et al, 1983, and Table 2). We used the fixed turnover rates for each soil carbon pool for the entire LEF.…”

Soil‐atmosphere nitrogen oxide fluxes: Effects of root disturbance

“…Soils at the this site belong to the Los Guineos-Yunque association; the clay soil, classified as a Tropohumult, formed from fine textured residuum weathered from volcanic rock [Bocceciamp, 1977]. We worked in native subtropical wet forest vegetation generally dominated by Dacryodes excelsa [Brown et al, 1983]. At our particular site the palm Prestoea montana was abundant.…”

“…Annual precipitation at Sabana is approximately 2900 mm [Scatena, 1989]; mean monthly temperatures vary little, ranging from 23.5 ø to 27.0øC [Brown et al, 1983]. Soils at the this site belong to the Los Guineos-Yunque association; the clay soil, classified as a Tropohumult, formed from fine textured residuum weathered from volcanic rock [Bocceciamp, 1977].…”