scholarly journals Floristic and structure of an Amazonian primary forest and a chronosequence of secondary succession

2016 ◽  
Vol 46 (2) ◽  
pp. 133-150 ◽  
Author(s):  
Camila Valéria de Jesus SILVA ◽  
João Roberto dos SANTOS ◽  
Lênio Soares GALVÃO ◽  
Ricardo Dal'Agnol da SILVA ◽  
Yhasmin Mendes MOURA

ABSTRACT The analysis of changes in species composition and vegetation structure in chronosequences improves knowledge on the regeneration patterns following land abandonment in the Amazon. Here, the objective was to perform floristic-structural analysis in mature forests (with/without timber exploitation) and secondary successions (initial, intermediate and advanced vegetation regrowth) in the Tapajós region. The regrowth age and plot locations were determined using Landsat-5/Thematic Mapper images (1984-2012). For floristic analysis, we determined the sample sufficiency and the Shannon-Weaver (H'), Pielou evenness (J), Value of Importance (VI) and Fisher's alpha (α) indices. We applied the Non-metric Multidimensional Scaling (NMDS) for similarity ordination. For structural analysis, the diameter at the breast height (DBH), total tree height (Ht), basal area (BA) and the aboveground biomass (AGB) were obtained. We inspected the differences in floristic-structural attributes using Tukey and Kolmogorov-Smirnov tests. The results showed an increase in the H', J and α indices from initial regrowth to mature forests of the order of 47%, 33% and 91%, respectively. The advanced regrowth had more species in common with the intermediate stage than with the mature forest. Statistically significant differences between initial and intermediate stages (p<0.05) were observed for DBH, BA and Ht. The recovery of carbon stocks showed an AGB variation from 14.97 t ha-1 (initial regrowth) to 321.47 t ha-1 (mature forests). In addition to AGB, Ht was also important to discriminate the typologies.

2018 ◽  
Vol 53 (10) ◽  
pp. 1109-1118
Author(s):  
Reginaldo Antonio Medeiros ◽  
Haroldo Nogueira de Paiva ◽  
Flávio Siqueira D’Ávila ◽  
Helio Garcia Leite

Abstract: The objective of this work was to evaluate the growth and yield of teak (Tectona grandis) stands at different spacing and in different soil classes. Twelve spacing were evaluated in an Inceptisol and Oxisol, in plots with an area of 1,505 or 1,548 m2, arranged in a completely randomized design with nine replicates. The teak trees were measured at 26, 42, 50, and 78 months of age. Total tree height was less affected by spacing. Mean square diameter was greater in wider spacing, whereas basal area and total volume with bark were greater in closer spacing. An increase in volume with bark per tree was observed with the increase of useful area per plant. For teak trees, growth stagnation happens earlier, the growth rate is higher in closer spacing, and the plants grow more in the Inceptisol than in the Oxisol.


Author(s):  
Tatiana Stankova ◽  
Veselka Gyuleva ◽  
Dimitar Dimitrov ◽  
Hristina Hristova ◽  
Ekaterina Andonova

Species of the genus Paulownia have been introduced to Bulgaria since the beginning of the XXthcentury and their multipurpose uses - as ornamental trees, for wood and biomass production- have been tested ever since. We present a study, which examines the early growth of four Paulowniaclones at southern locations in Bulgaria and derives biometric models for dendromass estimationof juvenile Paulownia trees.The data originated from two experimental plantations established on nursery land using one-yearoldin vitro propagated plant material. Forty six, 1 to 3 year-old saplings from two clones of P. tomentosaand two P. elongata × P. fortunei hybrids were sampled. Their stem biomass was modeledas a function of the breast height tree diameter and total tree height or the stem diameter aloneand a set of goodness-of-fit criteria was applied to select the most adequate among the 29 testedformulations. The regression models were fitted in log-transformed form to the logarithm of thestem biomass and MM correction factor for bias was applied to the back-transformed predictiondata. Two allometric relationships were derived, which adequately assess stem dendromass ofyoung Paulownia sp. from easily measurable tree characteristics. Both models are applicable forstem biomass estimation of juvenile Paulownia trees of diameter up to 5 cm and total height upto 3.5 m.


1988 ◽  
Vol 3 (4) ◽  
pp. 123-125 ◽  
Author(s):  
J. P. McTague ◽  
W. F. Stansfield

Abstract Total outside and inside bark cubic foot volume equations are presented for southwestern ponderosa pine (Pinus ponderosa) that are functions of total tree height, diameter breast height, and Girard form class. These equations are appropriate for trees of any size or age, and no distinction is made between "blackjack" and "yellow pine" trees. Equations are included to predict merchantable volume to any upper stem diameter or merchantable height. Taper and merchantable height functions are indirectly derived from the merchantable volume equations. West. J. Appl For. 3(4):123-125, October 1988.


2017 ◽  
Vol 26 (2) ◽  
pp. 148 ◽  
Author(s):  
Grant Wardell-Johnson ◽  
Liam Crellin ◽  
Casey Napier ◽  
Garrett Meigs ◽  
Alyssa Stevenson ◽  
...  

Tall eucalypt old-growth forests are notable for their large, old (i.e. venerable) trees and have both significant conservation value and high carbon stores. We investigated whether canopy height and biomass had recovered in an old-growth red tingle (Eucalyptus jacksonii) forest 78 years after a high-intensity fire. We recorded species, diameter, hollow butting and height of all 596 trees >10-cm diameter at breast height, as well as fine and coarse woody debris, in a 3.55-ha plot near Nornalup, south-western Australia. Pre-fire canopy height was estimated by allometrics derived from tree height and diameter, and diameter and length of recently fallen branches. Of the basal area (75.0 m2 ha–1), 92.7% was eucalypt (chiefly E. jacksonii), with regeneration accounting for only 8.5% of the total. Although canopy species composition apparently did not change following fire, stand height and biomass had not recovered to pre-1937 levels by 2015. Canopy height remained 5.06 m (11%) less and biomass 25% less, 78 years after the fire. The combination of intense fire and a warmer, drier climate appears to have prevented recovery of forest height and structure at this site. These findings indicate that ecologically important, venerable trees are increasingly vulnerable to canopy fire and climate change.


Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1104
Author(s):  
Zdeněk Adamec ◽  
Radim Adolt ◽  
Karel Drápela ◽  
Jiří Závodský

Research Highlights: Determination of merchantable wood volume is one of the key preconditions for sustainable forest management. This study explores accuracy of calibrated predictions of merchantable wood volume of Norway spruce (Picea abies (L.) H. Karst.) using stem taper curves (STC) in a form of a mixed model. Background and Objectives: The study is devoted to the determination of merchantable wood volume (over bark) of individual standing stems based on the integration of an STC model calibrated using upper diameter measurements. Various options of upper diameter measurement were tested and their impact on the accuracy of merchantable wood volume prediction was evaluated. Materials and Methods: To model stem taper curves, a Kozak 02 function was applied in a form of a nonlinear, mixed effects model. Accuracies of calibrated merchantable wood volume predictions obtained through remote (optical) upper diameter measurements were compared to accuracies corresponding to contact measurements by a caliper. The performance of two alternative methods used in the Czech National Forest Inventory (NFI) and forestry practice, involving diameter at breast height and total tree height as the only predictors, were also tested. The contact measurements were performed at identical stem positions after felling the respective sample tree. The calibration was done in order to account for factors inherent in particular location, and, optionally, also in a particular sample stem (within the respective location). Input data was sourced as part of a dedicated survey involving the entire territory of the Czech Republic. In total, 716 individual spruce trees were measured, felled and analysed at 169 locations. Results: In general, the best merchantable volume predictions were obtained by integrating the STC fitted (and calibrated) by minimising errors of stem cross-sectional areas instead of diameters. In terms of calibrated predictions, using single-directional, caliper measurement of upper diameter at 7 m (after felling) led to the best accuracy. In this case, the observed mean bias of merchantable volume prediction was only 0.63%, indicating underestimation. The best optical calibration strategy involved upper diameter measurements at two heights (5 and 7 m) simultaneously. Bias of this volume prediction approach was estimated at 2.1%, indicating underestimation. Conclusions: Concerning the prediction of merchantable stem volume of standing Norway spruce trees, STC calibration using two optical upper diameter measurements (at 5 and 7 m) was found to be practically applicable, provided a bias up to 3.7% can be accepted. This method was found to be more accurate than the existing national alternatives using diameter at breast height and the total tree height as the only predictors.


2008 ◽  
Vol 34 (3) ◽  
pp. 137-143
Author(s):  
Jan Lukaszkiewicz ◽  
Marek Kosmala

This article evaluates the possibility of determining tree age based simultaneously on diameter at breast height (dbh) (1.3 m [4.3 ft]) and total tree height using common lime, common ash, and horsechestnut species. The first step was the identification and measuring groups of trees growing in similar conditions (streetside trees in Warsaw area, Poland) in which planting ages were known (mainly from archives). Next, multifactorial regression model was developed describing the growth of both tree parameters (dbh and height) over time. In the majority of cases, plotting tree age against diameter and height yielded a regression coefficient r value and determination coefficient r 2value above 0.9. For graphic interpretation of elaborated multifactorial models, nomograms were applied. This kind of graph allows explaining tree age based on both dbh and height of trees. Another step was verification. The resulting model was applied to unrelated groups of trees of known age. Mean bias values were established for each model. The difference between the actual age and mean age calculated with the model was less than ±15%. Presented model, although not meant for application to individual trees, might be useful to determine the age of groups of trees growing along streets and roads.


2011 ◽  
Vol 59 (7) ◽  
pp. 640 ◽  
Author(s):  
J. H. Jonson ◽  
D. Freudenberger

In the south-western region of Australia, allometric relationships between tree dimensional measurements and total tree biomass were developed for estimating carbon sequestered in native eucalypt woodlands. A total of 71 trees representing eight local native species from three genera were destructively sampled. Within this sample set, below ground measurements were included for 51 trees, enabling the development of allometric equations for total biomass applicable to small, medium, and large native trees. A diversity of tree dimensions were recorded and regressed against biomass, including stem diameter at 130 cm (DBH), stem diameter at ground level, stem diameter at 10 cm, stem diameter at 30 cm, total tree height, height of canopy break and mean canopy diameter. DBH was consistently highly correlated with above ground, below ground and total biomass. However, measurements of stem diameters at 0, 10 and 30 cm, and mean canopy diameter often displayed equivalent and at times greater correlation with tree biomass. Multi-species allometric equations were also developed, including ‘Mallee growth form’ and ‘all-eucalypt’ regressions. These equations were then applied to field inventory data collected from three locally dominant woodland types and eucalypt dominated environmental plantings to create robust relationships between biomass and stand basal area. This study contributes the predictive equations required to accurately quantify the carbon sequestered in native woodland ecosystems in the low rainfall region of south-western Australia.


2012 ◽  
Vol 51 (No. 4) ◽  
pp. 147-154 ◽  
Author(s):  
E. Cienciala ◽  
M. Černý ◽  
J. Apltauer ◽  
Z. Exnerová

This material describes parameterization of allometric functions applicable to biomass estimation of European beech trees. It is based on field data from destructive measurements of 20 full-grown trees with diameter at breast height (dbh) from 5.7 to 62.1 cm. The parameterization was performed for total tree aboveground biomass (AB; besides stump), stem and branch biomass, respectively. The allometric functions contained two or three parameters and used dbh either as a single independent variable or in combination with tree height (H). These functions explained 97 to 99% of the variability in the measured AB. The most successful equation was that using both dbh and H as independent variables in combination with three fitted parameters. H, as the second independent variable, had rather a small effect on improving the estimation: in the case of AB, H as independent variable improved prediction accuracy by 1&ndash;2% whereas in the case of branch biomass by about 5%. The parameterized biomass equations are applicable to tree specimens of European beech grown in typically managed forests.


1981 ◽  
Vol 113 (3) ◽  
pp. 199-203
Author(s):  
T. E. Nebeker ◽  
O. P. Hackney ◽  
R. R. Hocking

AbstractA technique is presented that requires no direct measurement of gallery length to estimate the total gallery length. Required to obtain the estimate are: (1) an appropriate model for time of year, sample period, and host, (2) tree diameter at breast height, (3) length of infested bole, (4) total tree height, and (5) inner bark thickness. The technique is accurate, less time consuming, and less expensive than direct estimation techniques.


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