scholarly journals Allometric Relationships for Estimation of Above-Ground Biomass in Young Turkey Oak (Quercus cerris L.) Stands in Albania

2018 ◽  
Vol 14 (1) ◽  
pp. 65-81 ◽  
Author(s):  
Erion Istrefi ◽  
Elvin Toromani ◽  
Nehat Çollaku

Abstract The study objective was the determination of allometric relationships to estimate aboveground biomass in young Q. cerris stands growing in various sites in Albania. The equations described here are developed for Q. cerris forest stands managed as coppice. The total aboveground biomass of sampled trees varied from 10.67 to 19.71 kg with a stem diameter at 1.3 m (DBH) from 7.65 to 9.7 cm, and height from 5.26 to 7.6 m. Stem biomass comprised, on average, 69.6 %, while branch biomass was 24.3 %, and leaf biomass,6% on the total aboveground biomass of the sampled oak trees. Total aboveground biomass was predicted with the highest accuracy from linear and non-linear regression equations. Total aboveground biomass and the biomass of tree compartments were predicted with a notable accuracy from DBH where the allometric model efficiency exceeded 93%. Biomass expansion factors (BEFs) showed a stronger dependency on diameter at breast height and a weaker relationship with age. The age-dependence relationship found in our study was closely related to site productivity. The variability in aboveground biomass among sampled sites indicated that local site conditions cause this difference. These new equations for Q.cerris might be applicable in the framework of the Albanian National Forest Inventory for estimation of carbon accounting from forest ecosystems and will contribute to the sustainable management of oak forests.

2021 ◽  
Vol 22 (2) ◽  
Author(s):  
Karyati Karyati ◽  
Kusno Yuli Widiati ◽  
Karmini Karmini ◽  
Rachmad Mulyadi

Abstract. Karyati, Widiati KY, Karmini, Mulyadi R. 2021. The allometric relationships for estimating aboveground biomass and carbon stock in an abandoned traditional garden in East Kalimantan, Indonesia. Biodiversitas 22: 751-762. The existence of traditional gardens after abandonment process has a role based on ecological and economic aspects. To estimate the biomass and carbon stock in the abandoned traditional gardens, specific allometric equations are required. The aim of this study was to develop allometric equations to estimate biomass of plant parts (leaf, branch, trunk, and aboveground biomass (AGB)) through tree dimensions variables (diameter at breast height (DBH), total tree height, and tree bole height). The relationships between stem biomass, AGB and tree dimensions were very strong indicated by the relatively high adjusted R2 value. The moderately strong relationships were shown between branch biomass and tree dimensions, meanwhile, the relationship between leaf biomass and tree dimensions was very weak. The specific allometric equations for estimating biomass and carbon stocks that are suitable for tree species and/or forest stands at a particular site are very useful for calculating the carbon stocks and sequestration. The appropriate biomass and carbon stock calculation are needed to determine policies related to global climate change.


1998 ◽  
Vol 63 ◽  
Author(s):  
P. Smiris ◽  
F. Maris ◽  
K. Vitoris ◽  
N. Stamou ◽  
P. Ganatsas

This  study deals with the biomass estimation of the understory species of Pinus halepensis    forests in the Kassandra peninsula, Chalkidiki (North Greece). These  species are: Quercus    coccifera, Quercus ilex, Phillyrea media, Pistacia lentiscus, Arbutus  unedo, Erica arborea, Erica    manipuliflora, Smilax aspera, Cistus incanus, Cistus monspeliensis,  Fraxinus ornus. A sample of    30 shrubs per species was taken and the dry and fresh weights and the  moisture content of    every component of each species were measured, all of which were processed  for aboveground    biomass data. Then several regression equations were examined to determine  the key words.


Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 234
Author(s):  
Linda Flade ◽  
Christopher Hopkinson ◽  
Laura Chasmer

In this follow-on study on aboveground biomass of shrubs and short-stature trees, we provide plant component aboveground biomass (herein ‘AGB’) as well as plant component AGB allometric models for five common boreal shrub and four common boreal short-stature tree genera/species. The analyzed plant components consist of stem, branch, and leaf organs. We found similar ratios of component biomass to total AGB for stems, branches, and leaves amongst shrubs and deciduous tree genera/species across the southern Northwest Territories, while the evergreen Picea genus differed in the biomass allocation to aboveground plant organs compared to the deciduous genera/species. Shrub component AGB allometric models were derived using the three-dimensional variable volume as predictor, determined as the sum of line-intercept cover, upper foliage width, and maximum height above ground. Tree component AGB was modeled using the cross-sectional area of the stem diameter as predictor variable, measured at 0.30 m along the stem length. For shrub component AGB, we achieved better model fits for stem biomass (60.33 g ≤ RMSE ≤ 163.59 g; 0.651 ≤ R2 ≤ 0.885) compared to leaf biomass (12.62 g ≤ RMSE ≤ 35.04 g; 0.380 ≤ R2 ≤ 0.735), as has been reported by others. For short-stature trees, leaf biomass predictions resulted in similar model fits (18.21 g ≤ RMSE ≤ 70.0 g; 0.702 ≤ R2 ≤ 0.882) compared to branch biomass (6.88 g ≤ RMSE ≤ 45.08 g; 0.736 ≤ R2 ≤ 0.923) and only slightly better model fits for stem biomass (30.87 g ≤ RMSE ≤ 11.72 g; 0.887 ≤ R2 ≤ 0.960), which suggests that leaf AGB of short-stature trees (<4.5 m) can be more accurately predicted using cross-sectional area as opposed to diameter at breast height for tall-stature trees. Our multi-species shrub and short-stature tree allometric models showed promising results for predicting plant component AGB, which can be utilized for remote sensing applications where plant functional types cannot always be distinguished. This study provides critical information on plant AGB allocation as well as component AGB modeling, required for understanding boreal AGB and aboveground carbon pools within the dynamic and rapidly changing Taiga Plains and Taiga Shield ecozones. In addition, the structural information and component AGB equations are important for integrating shrubs and short-stature tree AGB into carbon accounting strategies in order to improve our understanding of the rapidly changing boreal ecosystem function.


2021 ◽  
Vol 13 (8) ◽  
pp. 1595
Author(s):  
Chunhua Li ◽  
Lizhi Zhou ◽  
Wenbin Xu

Wetland vegetation aboveground biomass (AGB) directly indicates wetland ecosystem health and is critical for water purification, carbon cycle, and biodiversity conservation. Accurate AGB estimation is essential for the monitoring and supervision of ecosystems, especially in seasonal floodplain wetlands. This paper explored the capability of spectral and texture features from the Sentinel-2 Multispectral Instrument (MSI) for modeling grassland AGB using random forest (RF) and extreme gradient boosting (XGBoost) algorithms in Shengjin Lake wetland (a Ramsar site). We use five-fold cross-validation to verify the model effectiveness. The results indicated that the RF and XGBoost models had a robust and efficient performance (with root mean square error (RMSE) of 126.571 g·m−2 and R2 of 0.844 for RF, RMSE of 112.425 g·m−2 and R2 of 0.869 for XGBoost), and the XGBoost models, by contrast, performed better. Both traditional and red-edge vegetation indices (VIs) obtained satisfactory results of AGB estimation (RMSE = 127.936 g·m−2, RMSE = 125.879 g·m−2 in XGBoost models, respectively), with the red-edge VIs contributed more to the AGB models. Moreover, we selected eight gray-level co-occurrence matrix (GLCM) textures calculated by four processing window sizes using the mean value of four offsets, and further analyzed the results of three analysis sets. Textures derived from traditional and red-edge bands using a 7 × 7 window size performed better in biomass estimation. This finding suggested that textures derived from the traditional bands were as important as the red-edge bands. The introduction of textures moderately improved the accuracy of modeling AGB, whereas the use of textures alo ne was not satisfactory. This research demonstrated that using the Sentinel-2 MSI and the two ensemble algorithms is an effective method for long-term dynamic monitoring and assessment of grass AGB in seasonal floodplain wetlands, which can support sustainable management and carbon accounting of wetland ecosystems.


2010 ◽  
Vol 25 (4) ◽  
pp. 203-209 ◽  
Author(s):  
Thomas W. McGinnis ◽  
Christine D. Shook ◽  
Jon E. Keeley

Abstract Quantification of biomass is fundamental to a wide range of research and natural resource management goals. An accurate estimation of plant biomass is essential to predict potential fire behavior, calculate carbon sequestration for global climate change research, assess critical wildlife habitat, and so forth. Reliable allometric equations from simple field measurements are necessary for efficient evaluation of plant biomass. However, allometric equations are not available for many common woody plant taxa in the Sierra Nevada. In this report, we present more than 200 regression equations for the Sierra Nevada western slope that relate crown diameter, plant height, crown volume, stem diameter, and both crown diameter and height to the dry weight of foliage, branches, and entire aboveground biomass. Destructive sampling methods resulted in regression equations that accurately predict biomass from one or two simple, nondestructive field measurements. The tables presented here will allow researchers and natural resource managers to easily choose the best equations to fit their biomass assessment needs.


1983 ◽  
Vol 13 (5) ◽  
pp. 773-781 ◽  
Author(s):  
F. Stuart Chapin III

Seasonal patterns of biomass, nitrogen (N), and phosphorus (P) were determined for major plant parts of the deciduous shrub Vacciniumuliginosum L. and the evergreen shrub Ledumgroenlandicum Oeder. in a black spruce (Piceamariana (Mill.) B.S.P.) forest in interior Alaska. New growth comprised 52 ± 7% of aboveground biomass in Vaccinium compared with the evergreen Ledum for which a maximum of 38 ± 3% of aboveground biomass was new growth. In Vaccinium the spring decline in leaf N and P concentration was due to dilution by increasing leaf biomass, whereas the autumn decline in N and P concentration was due to retranslocation, at which time 68–72% of leaf N and P was retranslocated from leaves. In contrast, the entire decline in N and P concentration of new growth in Ledum was due to dilution by increasing leaf biomass. Uptake contributed 60–68% of the maximum N and P requirement for aboveground growth of Vaccinium, with the remainder coming from stored reserves. Ledum supported 71–79% of its aboveground nutrient requirement by direct uptake from soil and may have been less dependent upon stored nutrient reserves. Vaccinium and Ledum together comprised only 0.8–2.8% of the standing crop of aboveground vascular biomass and N and P pools at Washington Creek but contributed 16% of vascular aboveground production and 19–24% of the N and P cycled annually by vascular plants. The importance of understory shrubs is due to their small support structure and rapid turnover of biomass and nutrients (34–43% of aboveground pools annually) relative to that of the trees (2–5% annually). Understory shrubs at Washington Creek and in other evergreen forests are much more important in nutrient cycling than their small biomass would suggest.


Author(s):  
Radek Pokorný ◽  
Petra Rajsnerová ◽  
Jiří Kubásek ◽  
Irena Marková ◽  
Ivana Tomášková

Aboveground biomass, allometric relationships and early to late wood proportions were investigated in two even-aged monocultures of Norway spruce (Picea abies [L.] Karst) located at mountain and highland localities of the Czech Republic. However similar stand age and tree size, mountain trees comparing to them from highland showed less/tapering stems, lower aboveground biomass and lower stem wood density along the whole stem vertical profile as a result of different early to late wood proportion. These proportions were 79 % and 54 % for early wood, and 21 % and 46 % for late wood within mean stem annual circle in mountain and highland locality, respectively. These different proportions seem to reflected site specific growing conditions, particularly highly sufficient water availability during spring time in mountain region- support early wood growth, whereas elevated air temperature during summer time in highland region stimulate late wood growth.


Author(s):  
Jacob I. Levine ◽  
Perry de Valpine ◽  
John J. Battles

Accurate estimation of forest biomass is important for scientists and policymakers interested in carbon accounting, nutrient cycling, and forest resilience. Estimates often rely on the allometry of trees; however, limited datasets, uncertainty in model form, and unaccounted for sources of variation warrant a re-examination of allometric relationships using modern statistical techniques. We asked the following questions: (1) Is there among-stand variation in allometric relationships? (2) Is there nonlinearity in allometric relationships? (3) Can among-stand variation or nonlinearities in allometric equations be attributed to differences in stand age? (4) What are the implications for biomass estimation? To answer these questions, we synthesized a dataset of small trees from six different studies in the White Mountains of New Hampshire. We compared the performance of generalized additive models (GAMs) and linear models and found that GAMs consistently outperform linear models. The best-fitting model indicates that allometries vary among both stands and species and contain subtle nonlinearities which are themselves variable by species. Using a planned contrasts analysis, we were able to attribute some of the observed among-stand heterogeneity to differences in stand age. However, variability in these results point to additional sources of stand-level heterogeneity, which if identified could improve the accuracy of live-tree biomass estimation.


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