The estimation of temporal processes in tropical rain forest: a study of primary mixed dipterocarp forest in Indonesia

1985 ◽  
Vol 1 (2) ◽  
pp. 171-182 ◽  
Author(s):  
Soedarsono Riswan ◽  
J. B. Kenworthy ◽  
Kuswata Kartawinata
Keyword(s):  
Time Scale ◽  
Rain Forest ◽  
Tropical Rain Forest ◽  
Gap Formation ◽  
Growth Rings ◽  
Secondary Species ◽  
East Kalimantan ◽  
Forest Sites ◽  
Time Required ◽  
Individual Trees

ABSTRACTIn the absence of growth rings it is difficult to give a precise time scale for processes associated with the re-establishment of tropical rain forest. This paper explores other methods by which a time scale may be constructed. The proportions of primary and secondary species, an index of similarity, biomass measurements, girth dimensions and gap size are all considered from sites in East Kalimantan, Indonesia. Data from primary, secondary and experimentally cleared forest sites are compared to estimate the minimum time required for various phases involved in the re-establishment of tropical rain forest after disturbance. A simple model is proposed to accommodate the data and other estimates in the literature. The model predicts a minimum period for the stablization of secondary species numbers as 60–70 years and the replacement of primary species as 150 years at which point gap formation is initiated. After approximately 220–250 years biomass stabilizes while individual trees exist for over 500 years.

scholarly journals Tree seedling performance in canopy gaps in a tropical rain forest at Nouragues, French Guiana

1998 ◽  
Vol 14 (2) ◽  
pp. 119-137 ◽  
Author(s):  
PETER J. VAN DER MEER ◽  
FRANK J. STERCK ◽  
FRANS BONGERS
Keyword(s):  
Rain Forest ◽  
Tropical Rain Forest ◽  
French Guiana ◽  
Environmental Heterogeneity ◽  
Canopy Gaps ◽  
Gap Formation ◽  
Tree Seedling ◽  
Growth And Survival ◽  
Closed Forest ◽  
Forest Conditions

The effect of natural canopy gaps on the performance of naturally occurring tree seedling populations was studied in a tropical rain forest in French Guiana. This was done at two levels of scale. Firstly, on a 20 m × 250 m forest transect intersecting four canopy gaps, it was investigated how patterns of recruitment, growth and survival of seedlings of Cecropia obtusa, Dicorynia guianensis and Pourouma bicolor differed between canopy gaps and closed forest. Secondly, for one large natural canopy gap, performance of seedling cohorts established before (‘pre-gap’ cohorts) and after (‘post-gap’ cohorts) gap formation was studied in relation to environmental heterogeneity. The direct site factor (DSF) was used as an indicator of light availability in the gap zone. Cecropia specialised in large gaps, and also in specific sites within the large gap: seedling performance was increased by light, and by dead wood. Pourouma mainly germinated under closed forest conditions, where it can survive for a long period until a canopy gap is formed nearby. Pourouma seedlings adjusted well to the new gap environment but they did not specialise in specific places within the gap. Seedling location of Pourouma seedlings was mainly determined by accidental positioning before gap formation. Dicorynia was able to germinate both in gaps and under closed forest conditions. Although the number of gaps studied in this study was low, the results show that seedling establishment, early growth and survival of the three tree species were affected by canopy gaps and by the environmental heterogeneity within a large gap.

scholarly journals Classification of Tropical Rain Forest East Kalimantan Using Image Processing and Backpropagation Neural Network Algorithm

2019 ◽  
Vol 8 (2S11) ◽  
pp. 2586-2589
Keyword(s):  
Neural Network ◽  
Image Processing ◽  
Rain Forest ◽  
Tropical Rain Forest ◽  
Backpropagation Neural Network ◽  
East Kalimantan ◽  
Network Algorithm ◽  
Neural Network Algorithm ◽  
High Level

Tropical Rain Forest located in East Kalimantan has a high level of biodiversity, with a high level of biodiversity in east kalimantan then it needs a method to classify the existing plants there. In the research, the researchers tried to classify 5 plants found in tropical rainforests, namely ShoreaBalangeran, Dryobalanopsbeccarii Dyer, Eusideroxylonzwageri, Duriokutejensis, Cerberamanghas. Classification is done by using backpropagation neural network algorithm combined with image processing, where the image used is the image of plant leaf. The result of this research is the classification of 5 species of this plant with precision value above 90% in order to become a supporter of botanical decision in determining the type of plant and become alternative reference to classify plants in tropical rain forest area.

scholarly journals Observations of total peroxy nitrates and total alkyl nitrates during the OP3 campaign: isoprene nitrate chemistry above a south-east Asian tropical rain forest

2012 ◽  
Vol 12 (2) ◽  
pp. 4797-4829
Author(s):  
E. Aruffo ◽  
P. Di Carlo ◽  
C. Dari-Salisburgo ◽  
F. Biancofiore ◽  
F. Giammaria ◽  
...  
Keyword(s):  
Dry Deposition ◽  
Rain Forest ◽  
Tropical Rain Forest ◽  
Thermal Dissociation ◽  
Ozone Production ◽  
Alkyl Nitrates ◽  
Direct Excitation ◽  
Forest Sites ◽  
New Instrument ◽  
Peroxy Nitrates

Abstract. Measurements of total peroxy nitrates (ΣRO2NO2, ΣPNs), total alkyl nitrates (ΣRONO2, ΣANs) and nitrogen dioxide (NO2) were made above the surface of a Malaysian tropical rain forest in Borneo, using a laser-induced fluorescence instrument developed at the University of L'Aquila (Italy). This new instrument uses the direct excitation of NO2 at 532 nm in order to measure its concentrations detecting by the NO2 fluorescence at wavelengths longer than 610 nm. ΣPNs and ΣANs are indirectly measured after their thermal dissociation into NO2. Observations showed enhanced levels of NO2 during nighttime, an increase of ΣPNs during the afternoon and almost no evident diurnal cycle of ΣANs. The diurnal maximums of 200 pptv for ΣPNs and ΣANs are well below the peaks reported in other forest sites. A box model constrained with measured species, reproduces well the observed ΣPNs, but overestimates ΣANs concentrations. The reason of this model-observation discrepancy could be a wrong parameterization in the isoprene nitrates (INs) chemistry mechanism. Sensitivity tests show that: (1) reducing the yield of INs from the reaction of peroxy nitrates with NO to almost the lowest values reported in literature (5%), (2) reducing the INs recycling to 70% and (3) keeping the INs dry deposition at 4 cm s−1, improve the agreement between modelled and measured ΣANs of 20% on average. These results imply that in the tropical rain forest, even if ΣPNs and ΣANs concentrations are lower than those observed in other North American forests, the yield and dry deposition of INs are similar. Another comparable result is that in the INs oxidation its recycling dominates with only a 30% release of NO2, which has implications on tropospheric ozone production and aerosol budget.

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