News Update on Tropical Forest Research: Jan – 2020

Beta-Diversity in Tropical Forest Trees

The high alpha-diversity of tropical forests has been amply documented, but beta-diversity—how species composition changes with distance—has seldom been studied. We present quantitative estimates of beta-diversity for tropical trees by comparing species composition of plots in lowland terra firme forest in Panama, Ecuador, and Peru. We compare observations with predictions derived from a neutral model during which habitat is uniform and only dispersal and speciation influence species turnover. we discover that beta-diversity is higher in Panama than in western Amazonia which patterns in both areas are inconsistent with the neutral model. In Panama, habitat variation appears to extend species turnover relative to Amazonia, where unexpectedly low turnover over great distances suggests that population densities of some species are bounded by so far unidentified processes. [1]

Gap‐Phase Regeneration in a Tropical Forest

Gap—phase regeneration of trees was described for the primary 5—6 yr of regrowth in 30 treefall gaps (20—705 m2) in tropical moist forest on Barro Colorado Island, Panama. Trees were classified as pioneers (saplings found only in gaps) or primary species (saplings found in gaps and within the understory of mature forest). In most of the gaps studied, stem densities rose rapidly after gap formation, then levelled off or declined by years 3—6. This pattern was particularly marked in some large gaps (>150 m2), where pioneers attained high densities, then experienced heavy mortality. Stem density of primary species didn’t vary with gap size. In large gaps the mean rate of growth tall was greater for pioneers than for primary species, size—class distribution broadened more for pioneers than for primary species, and early recruits of both regeneration types grew faster than later ones. [2]

Tropical forest and its environment.

The purpose of this book is “to assemble a dynamic picture of the trees and other plants of the forest, and therefore the climatic and other conditions which surround them”. This interacting system of forest and environment is viewed from the standpoints of plant ecology and physiology, and an effort is formed to synthesize the results of experiments in controlled environments with field measurements and observations. the most chapters deal with: analysis of the environment; the features, structure and classification of the tropical forest community; and therefore the physiology of tree growth in tropical forest. [3]

Tropical forest soils serve as substantial and persistent methane sinks

Although tropical forest soils contributed substantially global soil methane uptake, observations on soil methane fluxes in tropical forests are still sparse, especially in Southeast Asia , resulting in large uncertainty within the estimation of worldwide soil methane uptake. Here, we conducted two-year (from Sep, 2016 to Sep, 2018) measurements of soil methane fluxes during a lowland tropical forest site in Hainan island, China. At this tropical forest site, soils were substantial methane sink, and average annual soil methane uptake was estimated at 2.00 kg CH4-C ha−1 yr−1. [4]

Variability in Soil Physicochemical Properties and Microbial Population in an Indian Subtropical Forest

Aim: The below ground biota in forest ecosystems determine and regulate the supply of nutrients in soil and is probably going to point variation in population and metabolism with reference to the soil quality. Therefore, this study was undertaken to review the physico-chemical characteristics, bacterial-fungal population and soil respiration in several land use zones of a sub tropical Indian forest.

Methodology: Soil samples were collected from 0-20 cm depth employing a core sampler (5 cm diameter) and from 12 sub plots and three regions for physicochemical and microbiological studies. For measurement of soil respiration 20 cm x 20 cm soil blocks were cut from the sub plots. Sampling was done 3 times during a month for 2 months in natural sal (Shorea robusta) forest, bamboo plantation and wet land of the Chandaka-Dampara wild life sanctuary, India within the season (March-April). The samples were carried to the laboratory for experimental purpose. [5]


[1] Condit, R., Pitman, N., Leigh, E.G., Chave, J., Terborgh, J., Foster, R.B., Núnez, P., Aguilar, S., Valencia, R., Villa, G. and Muller-Landau, H.C., 2002. Beta-diversity in tropical forest trees. Science, 295(5555), (Web Link)

[2] Brokaw, N.V., 1985. Gap‐phase regeneration in a tropical forest. Ecology, 66(3), (Web Link)

[3] Longman, K.A. and Jeník, J., 1974. Tropical forest and its environment. Longman Group Ltd.. (Web Link)

[4] Tropical forest soils serve as substantial and persistent methane sinks
Jun-Fu Zhao, Shu-Shi Peng, Meng-Ping Chen, Guan-Ze Wang, Yi-Bin Cui, Li-Guo Liao, Ji-Guang Feng, Biao Zhu, Wen-Jie Liu, Lian-Yan Yang & Zheng-Hong Tan
Scientific Reports volume 9, (Web Link)

[5] Mishra, C. S. K., Samal, S., Acharya, P., Biswal, B. and Majhi, M. (2018) “Variability in Soil Physicochemical Properties and Microbial Population in an Indian Subtropical Forest”, Current Journal of Applied Science and Technology, 30(6), (Web Link)