A5056524848- Plant and soil sciences
- Agroforestry and silvopastoral systems
- Soil Carbon and Nitrogen Dynamics
- Scarabaeidae Beetle Taxonomy and Biogeography
- Soil Management and Crop Yield
- Forest ecology and management
- Peatlands and Wetlands Ecology
- Conservation, Biodiversity, and Resource Management
- Fire effects on ecosystems
- Botanical Research and Applications
- Plant Water Relations and Carbon Dynamics
- Iron oxide chemistry and applications
- Ecology and Vegetation Dynamics Studies
- Soil Science and Environmental Management
- Environmental and biological studies
- Coastal wetland ecosystem dynamics
- Amazonian Archaeology and Ethnohistory
- Mine drainage and remediation techniques
- Geochemistry and Elemental Analysis
- Soil and Water Nutrient Dynamics
- Arsenic contamination and mitigation
- Clay minerals and soil interactions
- Botany and Geology in Latin America and Caribbean
- Tree-ring climate responses
- Oil Palm Production and Sustainability
Center for International Forestry Research
2020-2023
International Potato Center
2021-2023
Instituto Venezolano de Investigaciones Científicas
2006-2022
Instituto de Ecología
2012
Academia Nacional de Medicina Venezuela
2005
University of the Andes
2005
Pennsylvania State University
1988
Abstract. Forest structure and dynamics vary across the Amazon Basin in an east-west gradient coincident with variations soil fertility geology. This has resulted hypothesis that may play important role explaining Basin-wide forest biomass, growth stem turnover rates. Soil samples were collected a total of 59 different plots analysed for exchangeable cations, carbon, nitrogen pH, several phosphorus fractions likely plant availability also quantified. Physical properties additionally examined...
Abstract. Soil samples were collected in six South American countries a total of 71 different 1 ha forest plots across the Amazon Basin as part RAINFOR project. They analysed for and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties examined an index soil physical quality proposed. A diverse range soils was found. For western areas near Andean cordillera southern northern fringes, tend to be distributed among lower pedogenetic levels, while central...
In a 1—ha plot of old—growth tierra firme forest near San Carlos de Rio Negro, Venezuela (northwest Amazon Basin), 88 trees ≥ 10 cm dbh out 786 die over 10—yr period. Most deaths resulted in the formation small (5—100 m 2 ) canopy openings (gaps). Occasionally, large gaps are formed this region when strong winds topple many together. five (single—treefall) and one (multiple—treefall) gap we studied changes soil fertility nutrient leaching, also plant establishment, mortality, growth during...
Abstract. Forest structure and dynamics have been noted to vary across the Amazon Basin in an east-west gradient a pattern which coincides with variations soil fertility geology. This has resulted hypothesis that may play important role explaining Basin-wide forest biomass, growth stem turnover rates. To test this assess importance of edaphic properties affect dynamics, plant samples were collected total 59 different plots Basin. Samples analysed for exchangeable cations, C, N, pH various P...
Abstract Tropical peat swamp forests are major global carbon (C) stores highly vulnerable to human intervention. In Peruvian Amazonia, palm swamps, the prevalent ecosystem, have been severely degraded through recurrent cutting of Mauritia flexuosa palms for fruit harvesting. While this can transform these C sinks into significant sources, magnitude fluxes in natural and disturbed conditions remains unknown. Here, we estimated emissions from degradation along a gradient comprising undegraded...
Abstract Mauritia flexuosa palm swamp, the prevailing Peruvian Amazon peatland ecosystem, is extensively threatened by degradation. The unsustainable practice of cutting whole palms for fruit extraction modifies forest's structure and composition eventually alters peat‐derived greenhouse gas (GHG) emissions. We evaluated spatiotemporal variability soil N 2 O CH 4 fluxes environmental controls along a swamp degradation gradient formed one undegraded site (Intact), moderately degraded (mDeg)...
Abstract. Soil samples were collected in six South American countries a total of 71 different 1 ha forest plots across the Amazon Basin as part RAINFOR project. They analysed for and exchangeable cations, C, N, pH with various P fractions also determined. Physical properties examined an index soil physical quality proposed. A diverse range soils was found. For western areas near Andean cordillera southern northern fringes, tend to be distributed among lower pedogenetic levels, while central...
There have been several ecological studies in forests of the Guayana Shield, but so far none had examined changes structure and composition evergreen with altitude. This study describes analyzes structure, species soil characteristics forest stands at different altitudinal zones Southeastern Venezuelan Guayana, order to explain patterns main factors that determine along gradient. Inventories 3 948 big (>10cm DBH) 1 328 small (5-10cm woody stems were carried out eleven plots, ranging from 0.1...
We evaluated changes of different soil nitrogen forms (total N, available ammonium and nitrate, total N in microbial biomass, mineralization) after conversion semideciduous dry tropical forest 5- 18-year-old pastures (YP OP, resp.) the western Llanos Venezuela. This evaluation was made at early rainy season, end during season. With few exceptions, no significant differences were detected three study sites. Compared to soils, YP showed losses from 4.2 62.9% nitrate 20.0 77.8%, depending on...
<p>Mauritia flexuosa palm swamp, the prevailing Peruvian Amazon peatland ecosystem, is</p><p>extensively threatened by degradation. The unsustainable practice of cutting whole</p><p>palms for fruit extraction modifies forest's structure and composition eventually</p><p>alters peat-derived greenhouse gas (GHG) emissions. We evaluated spatio-temporal</p><p>variability...
Abstract Background Amazon palm swamp peatlands are major carbon (C) sinks and reservoirs. In Peru, this ecosystem is widely threatened owing to the recurrent practice of cutting Mauritia flexuosa palms for fruit harvesting. Such degradation could significantly damage peat deposits by altering C fluxes through fine root productivity, mortality, decomposition rates which contribute regulate accumulation. Along a same formation, we studied an undegraded site (Intact), moderately degraded...