A5032361089- Forest ecology and management
- Ecology and Vegetation Dynamics Studies
- Plant Water Relations and Carbon Dynamics
- Ruminant Nutrition and Digestive Physiology
- Pasture and Agricultural Systems
- Soil Carbon and Nitrogen Dynamics
- Plant and animal studies
- Bioenergy crop production and management
- Agroforestry and silvopastoral systems
- Remote Sensing in Agriculture
- Tree-ring climate responses
- Conservation, Biodiversity, and Resource Management
- Botany and Geology in Latin America and Caribbean
- Remote Sensing and LiDAR Applications
- Species Distribution and Climate Change
- Atmospheric and Environmental Gas Dynamics
- Rangeland and Wildlife Management
- Plant responses to elevated CO2
- Soil and Water Nutrient Dynamics
- Fern and Epiphyte Biology
- Wildlife Ecology and Conservation
- Climate variability and models
- Soil Moisture and Remote Sensing
- Library Science and Administration
- Animal Ecology and Behavior Studies
University of Missouri–St. Louis
2013-2023
Independent Dance
2022
Lindenwood University
2018-2021
Sheffield Hallam University
2013
Western Maine Health
2013
University of Virginia
2010
DairyNZ
2009
Dexcel Pharma (United Kingdom)
2001-2007
Florida International University
2007
Smithsonian Environmental Research Center
2004
There are pressing reasons for developing a better understanding of net primary production (NPP) in the world's forests. These ecosystems play large role carbon budget, and their dynamics, which likely to be responding global changes climate atmospheric composition, have major economic implications impacts on biodiversity. Although there is long history forest NPP studies ecological literature, current ecosystem-level remains limited. Forest cannot directly measured; it must approached by...
To assess the diversity of tropical tree life histories, a conceptual framework is needed to guide quantitative comparative study many species. We propose one such framework, which focuses on long—term performance through ontogeny and over natural range microsites. For 6 yr we annually evaluated survival, growth, microsite conditions six non—pioneer species in primary wet forest at La Selva Biological Station, Costa Rica. The were: Lecythis ampla, Hymenolobium mesoamericanum, Dipteryx...
Information on net primary production in tropical forests is needed for the development of realistic global carbon budgets, projecting how these ecosystems will be affected by climatic and atmospheric changes, evaluating eddy covariance measurements forest flux. However, a review database commonly used to address issues shows that it has serious flaws. In this paper we synthesize data literature NPP old-growth produce consistent set forests. Studies biome have addressed only few components,...
As a partial explanation for the maintenance of high tree diversity in wet tropical forests, Janzen (1970) and Connell (1971) independently hypothesized that natural enemies act to increase spacing within these populations through disproportionately attack on progeny near adults. Both authors also minimum critical distance effect, because 100% mortality given We describe necessary sufficient conditions testing hypotheses, show attempts evaluate them have been hampered by use inappropriate...
During 1984–2000, canopy tree growth in old-growth tropical rain forest at La Selva, Costa Rica, varied >2-fold among years. The trees' annual diameter increments this 16-yr period were negatively correlated with means of daily minimum temperatures. variations also covaried the net carbon exchange terrestrial tropics as a whole, inferred from nearly pole-to-pole measurements atmospheric dioxide (CO 2 ) interpreted by an inverse tracer–transport model. Strong reductions and large releases...
Tropical rain forests have the highest tree diversity on earth. Nonrandom spatial distributions of these species in relation to edaphic factors could be one mechanism responsible for maintaining this diversity. We examined prevalence nonrandom trees and palms soil type topographic position ("edaphic biases") over a mesoscale (573 ha) old-growth tropical forest (TRF) landscape at La Selva Biological Station, Costa Rica. All ≥10 cm diameter were measured identified 1170 circular 0.01-ha plots...
Significance People are fascinated by the amazing diversity of tropical forests and will be surprised to learn that robust estimates number tree species lacking. We show there at least 40,000, but possibly more than 53,000, in tropics, contrast only 124 across temperate Europe. Almost all restricted their respective continents, Indo-Pacific region appears as species-rich America, with each these two regions being almost five times rich African forests. Our study shows most extremely rare,...
NASA's Global Ecosystem Dynamics Investigation (GEDI) is collecting spaceborne full waveform lidar data with a primary science goal of producing accurate estimates forest aboveground biomass density (AGBD). This paper presents the development models used to create GEDI's footprint-level (~25 m) AGBD (GEDI04_A) product, including description datasets and procedure for final model selection. The fit our are from compilation globally distributed spatially temporally coincident field airborne...
1 Do local edaphic factors over short environmental gradients affect the distribution and abundance of tree species in tropical rain forests? We addressed this question by examining responses to soil type, topographic position slope angle an upland old‐growth forest landscape Costa Rica, Central America. 2 The study area covered 216 ha non‐swamp old growth included replicated units such as ridgetop swale catenas, small watersheds, alluvial terraces. An existing soils map was refined using...
Disjunct eddy covariance in conjunction with continuous in‐canopy gradient measurements allowed for the first time to quantify fine‐scale source and sink distribution of some most abundant biogenic (isoprene, monoterpenes, methanol, acetaldehyde, acetone) photooxidized (MVK+MAC, acetone, acetic, formic acid) VOCs an old growth tropical rain forest. Our revealed substantial isoprene emissions (up 2.50 mg m −2 h −1 ) light‐dependent monoterpene 0.33 at peak dry season (April May 2003)....
1 Symbiotic arbuscular mycorrhizal (AM) fungi produce a recalcitrant AM-specific glycoprotein, glomalin, which could be substantial contributor to soil carbon (C). In this study we made first assessment of the standing stocks glomalin in tropical lowland rain forest (the La Selva Biological Station, Costa Rica) and tested whether concentrations varied over strong fertility gradient forest. 2 Mean levels top 10 cm soils were 3.94 ± 0.16 mg cm−3 (1.45 Mg C ha−1), accounting for approximately...
ABSTRACT We evaluated occurrence and abundance of lianas woody hemiepiphytes on canopy emergent tree species in primary tropical wet forest at the La Selva Biological Station, Costa Rica. Two pioneers, Cecropia obtusifolia C. insignis , lacked both hemiepiphytes. The seven non-pioneer differed significantly their loads For all species, two measures liana hemiepiphyte (the percentage crown occupied combined basal area descending roots stems) increased with diameter. In most trees ∵ 70 cm...
Abstract Increased atmospheric [CO 2 ] could theoretically lead to increased forest productivity (‘CO fertilization’). This mechanism was hypothesized as a possible explanation for biomass increases reported from tropical forests in the last 30+ years. We used unique long‐term records of annually measured stands (eighteen 0.5 ha plots, 10 years) and focal tree species (six species, 24 assess effects rainfall, temperature, on annual wood production neotropical rain forest. Our study area...
(1) This study assesses the frequency, rates of occurrence, and consequences physical damage to individuals nine canopy tree species in primary tropical rain forest at La Selva Biological Station, Costa Rica. (2) For all combined, frequency varied from 9 27% among five size classes. Frequency was negatively correlated with diameter growth for stems 1-30cm diameter. (3) Rates due falling litter ranged 1 7% year-' trees up 30 cm Calculated half-lives until death or increased 10 years 63 10-30...
We studied the landscape—level spatial variation in distribution and abundance of seven species canopy subcanopy palms a neotropical rain forest. Within 568 ha nonswamp old—growth lowland forest at La Selva Biological Station, Costa Rica, we sampled 516 intersections reserve—wide grid to systematically assess species' distributions across major edaphic gradients. found mosaics community structure related marked within—forest variability both soil topography. Total stem density this guild...
In a recent (1998) publication of Science, data from large number forest inventory plots were used to estimate biomass trends in old-growth tropical forests. Although no evidence was found net change mature Paleotropical forests, old growth the humid Neotropics inferred have been substantial carbon sink decades. Methodological artifacts affected this analysis, however. Many Neotropical measured strictly at breast height, where trees frequently buttresses and other protruberances. Because...