scholarly journals Diversity, Population Structure, and Above Ground Biomass in Woody Species on Ngomakurira Mountain, Domboshawa, Zimbabwe

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Clemence Zimudzi ◽  
Christopher Chapano

The diversity, structure, species composition, and above ground biomass of woody plants on Ngomakurira mountain in Zimbabwe were studied. A systematic random sampling approach was adopted to establish 52 sampling plots measuring 10 × 10 m across 3 study strata in the 1266 ha study area. Woody species occurring in each plot were identified and the circumferences of trees with diameters >8.0 cm at 1.3 m height were measured. A total of 91 species belonging to 74 genera and 39 families were identified in the sample plots. A Shannon-Wiener index mean value of 3.12 was obtained indicating high species diversity on the mountain. The DBH size class distribution showed inverse J distribution patterns across the three study strata, but with only 3 individual plants with DBH > 30 cm. Mean basal area was 15.21 m2 ha−1 with U. kirkiana and J. globiflora contributing approximately 30% of the basal area. The estimated above ground biomass ranged from 34.5 to 65.1 t ha−1. Kruskal-Wallis-H test showed no significant differences in species richness, stem density, basal area, above ground biomass, and evenness, across the study strata (p<0.05). Ngomakurira woodland has potential to regenerate due to the presence of many stems in the small diameter size classes.

2008 ◽  
Vol 24 (4) ◽  
pp. 355-366 ◽  
Author(s):  
Jérôme Chave ◽  
Jean Olivier ◽  
Frans Bongers ◽  
Patrick Châtelet ◽  
Pierre-Michel Forget ◽  
...  

AbstractThe dynamics of tropical forest woody plants was studied at the Nouragues Field Station, central French Guiana. Stem density, basal area, above-ground biomass and above-ground net primary productivity, including the contribution of litterfall, were estimated from two large permanent census plots of 12 and 10 ha, established on contrasting soil types, and censused twice, first in 1992–1994, then again in 2000–2002. Mean stem density was 512 stems ha−1 and basal area, 30 m2 ha−1. Stem mortality rate ranged between 1.51% and 2.06% y−1. In both plots, stem density decreased over the study period. Using a correlation between wood density and wood hardness directly measured by a Pilodyn wood tester, we found that the mean wood density was 0.63 g cm−3, 12% smaller than the mean of wood density estimated from the literature values for the species occurring in our plot. Above-ground biomass ranged from 356 to 398 Mg ha−1 (oven-dry mass), and it increased over the census period. Leaf biomass was 6.47 Mg ha−1. Our total estimate of aboveground net primary productivity was 8.81 MgC ha−1 y−1 (in carbon units), not accounting for loss to herbivory, branchfalls, or biogenic volatile organic compounds, which may altogether account for an additional 1 MgC ha−1 y−1. Coarse wood productivity (stem growth plus recruitment) contributed to 4.16 MgC ha−1 y−1. Litterfall contributed to 4.65 MgC ha−1 y−1 with 3.16 MgC ha−1 y−1 due to leaves, 1.10 MgC ha−1 y−1 to twigs, and 0.39 MgC ha−1 y−1 to fruits and flowers. The increase in above-ground biomass for both trees and lianas is consistent with the hypothesis of a shift in the functioning of Amazonian rain forests driven by environmental changes, although alternative hypotheses such as a recovery from past disturbances cannot be ruled out at our site, as suggested by the observed decrease in stem density.


2019 ◽  
Vol 8 (1) ◽  
pp. 20
Author(s):  
Randall W. Myster

Igap&oacute; forests are a key part of the Amazon.&nbsp; And so, it is important to know their floristics and physical structure, and how they may be influenced by their soil.&nbsp; The floristics and physical structure of 16 primary [1o] and secondary [2o] igap&oacute; forest plots in Loreto Province, Peru was described and linear regressions were computed to explore whether soil bulk density could predict structural parameters. In the 1o forest, Fabaceae, Malvaceae and Rubiaceae were the most common families and Calycophyllum spruceanum, Ceiba samauma, Inga spp., Cedrela odorata, Copaifera reticulata, Phytelephas macrocarpa, Guazuma rosea, and Piptadenia pteroclada were the most common species. And as flooding increased, bulk density, stem density, stem size, species richness, Fishers &alpha;, basal area and above-ground biomass all decreased. In the 2o forest, Urticaceae, Rubiaceae and Euphorbiaceae were the most common families and Cecropia membranacea, Sapium glandulosum, Pourouma guianensis and Byrsonima arthropoda were the most common species. The number of stems was greatest in the island 2o forest and lowest in the 1o forest under water for more than four months, and mean stem size, species richness, Fishers &alpha;, basal area and above-ground biomass was lowest in the sandy beach 2o forest and highest in the 1o forest under water one to two months. Soil bulk density predicted mean stem size, species richness and Fishers &alpha; well, where all three decreased as soils became more sandy. I conclude that as soil becomes less sandy with more clay content there is an increase in forest structural complexity, unpredictable flooding in 2o forests reduces structure more than the predictable flood pulse 1o forests receive, and soil bulk density may have a causal role for diversity in igap&oacute; forests.


2016 ◽  
Vol 8 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Sudam Charan SAHU ◽  
H.S. SURESH ◽  
N.H. RAVINDRANATH

The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB) of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters) were laid. The study showed the presence of 71 tree species belonging to 57 genera and 30 families. Dominant tree species was Shorea robusta with an importance value index (IVI) of 40.72, while Combretaceae had the highest family importance value (FIV) of 39.01. Mean stand density was 479 trees ha-1 and a basal area of 15.20 m2 ha-1. Shannon’s diversity index was 2.01 ± 0.22 and Simpson’s index was 0.85 ± 0.03. About 54% individuals were in the size between 10 and 20 cm DBH, indicating growing forests. Mean above ground biomass value was 98.87 ± 68.8 Mg ha-1. Some of the dominant species that contributed to above ground biomass were Shorea robusta (17.2%), Madhuca indica (7.9%), Mangifera indica (6.9%), Terminalia alata (6.9%) and Diospyros melanoxylon (4.4%), warranting extra efforts for their conservation. The results suggested that C-stocks of tropical dry forests can be enhanced by in-situ conserving the high C-density species and also by selecting these species for afforestation and stand improvement programs. Correlations were computed to understand the relationship between above ground biomass, diversity indices, density and basal area, which may be helpful for implementation of REDD+ (reduce emissions from deforestation and forest degradation, and foster conservation, sustainable management of forests and enhancement of forest carbon stocks) scheme.


2008 ◽  
Vol 65 (3) ◽  
pp. 447-468 ◽  
Author(s):  
A. Giriraj ◽  
M. S. R. Murthy ◽  
B. R. Ramesh

The composition, abundance, population structure and distribution patterns of the woody species having a girth at breast height of ≥ 10 cm were investigated in the tropical wet evergreen forests of the Kalakad-Mundanthurai Tiger Reserve in the southern Western Ghats, India. A 3 ha plot was established with an altitudinal range of 1170 to 1306 m. In the study plot 5624 individuals (mean density 1875 ha−1) covering 68 woody species belonging to 52 genera and 27 families were enumerated. The mean basal area was 47.01 m2 ha–1 and the Shannon and Simpson diversity indices were 4.89 and 0.95, respectively. Of these woody species nearly 51% are endemic to the Western Ghats. The four dominant species, Cullenia exarillata, Palaquium ellipticum, Aglaia bourdillonii and Myristica dactyloides, account for 34% of the trees and 67% of the basal area, and therefore constitute the main structure of the forest. Within this forest type, five species assemblages corresponding to altitudinal gradient were identified using correspondence analysis. Management of such mid elevation evergreen forests necessarily depends on knowledge of recognisable community types and their environmental variables. The present study provides essential background for formulating strategies for sustainable conservation of forest communities at the local level.


2000 ◽  
Vol 48 (6) ◽  
pp. 707 ◽  
Author(s):  
W. H. Burrows ◽  
M. B. Hoffmann ◽  
J. F. Compton ◽  
P. V. Back ◽  
L. J. Tait

Allometric equations are presented relating stem circumference to branch, leaf, trunk, bark, total above-ground and lignotuber biomass for Eucalyptus crebra F.Muell. (woodland trees), E. melanophloia Sol. Ex Gaerth. (both woodland and regrowth community trees) and E. populnea F.Muell. (woodland trees). There were no significant differences (P > 0.05) between the slopes of individual lognormal regression lines plotting stem circumference against total above-ground biomass for E. crebra, E. melanophloia and E. populnea. Root-to-shoot ratios and leaf area indices were also determined for the stands contributing to each regression. The regressions were then applied to measured eucalypt stems in the associated plant community to give estimates of each stand’s component (eucalypt tree fraction only) biomass per hectare. These eucalypt regressions were next applied to measured stems of each species on a total of 33 woodland sites in which these eucalypts individually contributed > 75% of total site basal area. Above-ground biomass/basal area relationships averaged 6.74 0.29 t m–2 basal area for 11 E. crebra sites, 5.11 0.28 t m–2 for 12 E. melanophloia sites and 5.81 0.11 t m–2 for 10 E. populnea sites. The mean relationship for all sites was 5.86 0.18 t m–2 basal area. The allometric relationships presented at both individual tree and stand levels, along with calculated biomass : basal area relationships, enable ready estimates to be made of above-ground biomass (carbon stocks) in woodlands dominated by these eucalypts in Queensland, assuming individual stem circumferences or community basal areas are known. However, to document changes in carbon stocks (e.g. for Greenhouse Gas Inventory or Carbon Offset trading purposes), more attention needs to be placed on monitoring fluxes in the independent variables (predictors) of these allometric equations.


2020 ◽  
Vol 13 (1) ◽  
pp. 165-174
Author(s):  
R Puc-Kauil ◽  
G Ángeles-Pérez ◽  
JR Valdéz-Lazalde ◽  
VJ Reyes-Hernández ◽  
JM Dupuy-Rada ◽  
...  

2022 ◽  
Author(s):  
K. A Sreejith ◽  
M. S Sanil ◽  
T. S Prasad ◽  
M. P Prejith ◽  
V. B Sreekumar ◽  
...  

Tropical forests have long been accepted for their productivity and ecosystem services on account of their high diversity and stand structural attributes. In spite of their significance, tropical forests, and especially those of Asia, remain understudied. Until recently, most forest inventories in Asia have concentrated on trees 10 cm in diameter. Floristic composition, plant species diversity, above-ground biomass, basal area, and diversity were investigated across different life forms and two-diameter classes in a large-scale 10-ha plot, in the undisturbed tropical seasonal rain forest of Southern Western Ghats, Kerala, India. The regeneration pattern of the study area was examined by evaluating fisher's alpha and IVI (Important Value Index) across three layers of vegetation (seedling, sapling, and tree). Within the plot, we recorded 25,390 woody plant species ≥1 cm dbh from 45 families, 91 genera, and 106 species. Plant density was 2539 woody individuals per hectare, with a basal area of 47.72 m2/ha and above-ground biomass of 421.77 Mg/ha. By basal area, density, and frequency, the Rubiaceae, Sapotaceae, and Malvaceae families were the most important. Small-diameter trees (1 cm ≤ dbh ≤10 cm) were found to be 78 percent of the total tree population, 20.2 percent of the basal area, and 1.4 percent of the aboveground biomass. They also possessed 6 percent more diversity at the family level, 10% more diversity at the genus level, and 12% more diversity at the species level than woody individuals under 10 cm dbh. Woody individuals of treelets life form and small-diameter classes were much more diverse and dense than the other groups, indicating that results based only on larger canopy trees and larger diameter class maybe not be an appropriate representation of the diversity status of a particular tropical forest type. The lower density of individuals in the initial girth class indicates the vulnerability of the forest system to anthropogenic, natural disturbance and a changing climate. Reduce the minimum diameter limit down to 1 cm, in contrast to 10 cm limit used in most of the evergreen forest inventories, revealed a high density and diversity in the lower stories.


2020 ◽  
Author(s):  
Rahul Kumar ◽  
Amit Kumar ◽  
Purabi Saikia

Abstract Background Above ground biomass (AGB) is a useful measure for assessing changes in forest structure and functional, and play a significant role in studying carbon stocks, the effect of deforestation and carbon sequestration on the global carbon balance. The present study aimed to study the relationship between AGB and community parameters in Sal forests of Eastern India through stratified random sampling by lying 92 belt transects each of 0.5 ha size. Results It recorded a high AGB (410.70 Mg ha-1), and carbon stock (Cp) (193.06 Mg C ha-1), and forest wise AGB ranged from 0.19 to 24.75 Mg ha-1 (mean 4.45 ± 0.45 SE). The spatial pattern of AGB showed that maximum studied forests (65%) had very low AGB (<5.00 Mg ha-1), and only one forests (1%) located in the northwest corner of Ranchi had very high AGB (>20 Mg ha-1). Species wise AGB ranged from 0.001 to 7074.94 Mg ha-1 (mean 106 ± 71 SE) and Shorea robusta with maximum basal area (120.81 m2 ha−1) contributed maximum AGB (64.87% of the total AGB), however, no similar trends have been observed in any other tree species. A significant positive correlation was observed between AGB and Cp (r=1.00, p<0.01), H’ (r= .58, p<0.01), Dmg (r= .31, p<0.01), Dmn (r= .49, p<0.01), ENS (r= .57, p<0.01), E (r= .26, p<0.05), and basal area (r= 0.71, p<0.05). However, a negative correlation of AGB was evident with CD (r= -.57, p<0.01), and density (r= - 0.17). Conclusions The relationships differed greatly among plant diversity attributes, basal area, density, AGB, and Cp within and among various forests and the strongest relationships within each forests were always those having greater richness (Dmg, Dmn), diversity (H, ENS), basal area or evenness (E). Estimation of forest Cp enables us to assess the amount of carbon loss during deforestation or the amount of carbon stored during forest regeneration. The present study will directly help in studying the response of climate change on ecosystem productivity, energy and nutrient flow, and for assessing the patterns of carbon sequestration in Indian forests under global climate change.


2016 ◽  
Vol 64 (1) ◽  
pp. 70-92 ◽  
Author(s):  
Mait Lang ◽  
Ando Lilleleht ◽  
Mathias Neumann ◽  
Karol Bronisz ◽  
Samir G. Rolim ◽  
...  

Abstract A generic regression model for above-ground biomass of forest stands was constructed based on published data (R2 = 0.88, RSE = 32.8 t/ha). The model was used 1) to verify two allometric regression models of trees from Scandinavia applied to repeated measurements of 275 sample plots from database of Estonian Network of Forest Research (FGN) in Estonia, 2) to analyse impact of between-tree competition on biomass, and 3) compare biomass estimates made with different European biomass models applied on standardized forest structures. The model was verified with biomass measurements from hemiboreal and tropical forests. The analysis of two Scandinavian models showed that older allometric regression models may give biased estimates due to changed growth conditions. More biomass can be stored in forest stands where competition between trees is stronger. The tree biomass calculation methods used in different countries have also substantial influence on the estimates at stand-level. A common database of forest biomass measurements from Europe in similar to pan-tropical tree measurement data may be helpful to harmonise carbon accounting methods.


1982 ◽  
Vol 60 (2) ◽  
pp. 117-125 ◽  
Author(s):  
V. J. Lieffers ◽  
Jennifer M. Shay

Shoots of Scirpus maritimus var. paludosus sprout from overwintered tubers in May. Stem growth is rapid and within 2–3 weeks lateral rhizomes extend outwards and produce tillers with new tubers at their bases. By August up to four new shoots are produced in a rhizome–shoot series. All aboveground biomass is dead by late October but tubers overwinter to develop the following growing season. The ratio of below- to above-ground biomass of the rhizome–shoot series increased from 0.20 to 0.76 from early to late summer. The ratio of below- to above-ground biomass of individual stems was highest at the youngest end of the rhizome–shoot series.Stem density and inflorescence and total biomass were monitored at three sites over three growing seasons. The sites had large fluctuations in salinity in response to changes in water depth. Among all sites, maximum stem density reached 380 stems/m2 by late July, slightly before the maximum standing crop of 625 g/m2 was attained. At one site, changes in water levels and salinity increased the peak aboveground standing crop 22-fold (from 27 to 600 g/m2) from 1978 to 1979. A mathematical equation predicting the seasonal aboveground standing crop of S. maritimus was developed using water depth and conductivity as predictor variables.


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