LAI and Leaf Biomass Allometric Equations for Three Common Tree Species in a Hyrcanian Temperate Forest

Despite the importance of Hyrcanian forests for biodiversity conservation, a few studies with biomass destruction has been done to predict biomass and carbon pools from this forest and there is a lack of knowledge in our country. Biomass and leaf area index (LAI) are important variables in many ecological and environmental applications and forest management. In this paper, allometric biomass and leaf area equations were developed for three common Hyrcanian tree species, Oriental Beech (Fagus orientalis Lipsky), Hornbeam (Carpinus Betulus Lipsky) and Chestnut- leaved Oak (Quercus castaneifolia C. A. Mey). To evaluate and estimate the leaf biomass and leaf area index of Oriental Beech, Horbeam and Chestnut-leaved Oak, 21, 27 and 17 individuals were selected and felled down, respectively. Tree characteristics such as diameter at breast height, total height, crown length and perpendicular diameters were measured. Destructive sampling was applied for determination of leaf biomass and LAI. Allometric equations were calculated for estimation of leaf biomass and LAI using simple linear regression and nonlinear regression analysis. The equations were compared based on several modelling parameters. Model comparison and selection were based on R2, Akaike’s information criterion (AIC), prediction error sums of squares, model standard error estimate (SEE), ΔAIC, and a correction factor. Based on the results, the mean values of leaf area, leaf biomass and LAI for Oriental Beech were 53.05 cm2, 0.176 gr, 2.16, for Hornbeam were 27.2 cm2, 0.128 gr, 1.13 and for Chestnut-leaved Oak were 62.419 cm2, 0.401 gr, 2.26, respectively. The highest significant correlation for Oriental Beech was found between LAI and total height (R2adj= 0. 931), the highest significant correlation for Hornbeam was found between LAI and Dbh (R2adj = 0. 956) and the highest significance for Chestnut-leaved Oak was found between LAI and SqrtDbh (R2adj = 0. 956). Also, the best equations were obtained by means of an exponential regression model for Oriental Beech, the Log-transformed regression model for Hornbeam and of a transformed regression model for Chestnut-leaved Oak.

Carbon storage in biomass,litter,and soil of different native and introduced fast-growing tree plantations in the South Caspian Sea

Replantation of degraded forest using rapidgrowth trees can play a significant role in global carbon budget by storing large quantities of carbon in live biomass,forest floor,and soil organic matter.We assessed the potential of 20-year old stands of three rapid-growth tree species,including Alnus subcordata,Populus deltoides and Taxodium distichum,for carbon(C) storage at ecosystem level.In September 2013,48 replicate plots(16 m × 16 m) in 8 stands of three plantations were established.36 trees were felled down and fresh biomass of different components was weighed in the field.Biomass equations were fitted using data based on the 36 felled trees.The biomass of understory vegetation and litter were measured by harvesting all the components.The C fraction of understory,litter,and soil were measured.The ecosystem C storage was as follows: A.subcordata(626.5 Mg ha) [ P.deltoides(542.9Mg ha) [ T.distichum(486.8 Mg ha)(P \ 0.001),of which78.1–87.4% was in the soil.P.deltoides plantation reached the highest tree biomass(206.6 Mg ha),followed by A.subcordata(134.5 Mg ha) and T.distichum(123.3 Mg ha).The highest soil C was stored in theplantation of A.subcordata(555.5 Mg ha).The C storage and sequestration of the plantations after 20 years were considerable(25–30 Mg hayear) and broadleaves species had higher potential.Native species had a higher soil C storage while the potential of introduced species for live biomass production was higher.

Above- and below-ground biomass and carbon stocks of different tree plantations in central Iran

In arid and semi-arid lands using industrial wastewater for irrigating tree plantations offers a great opportunity to fulfill the purpose of Clean Development Mechanism by sequestering carbon in living tissues as well as in soil. Selection of tree for plantation has a great effect on the goal achievements, especially when the managers deal with afforestation projects rather than reforestation projects. The objective of this study was to quantify the above- and below-ground biomass accumulation and carbon storages of the 17-year-old monoculture plantations of mulberry (Morus alba L.), black locust (Robinia pseudoacacia L.), Eldar pine (Pinus eldarica Medw.) and Arizona cypress (Cupressus arizonica Greene) planted in central Iran. To assess the potential carbon storage, we destructively measured individual above- and below-ground tree biomass and developed and scaled models at stand level. Furthermore, carbon content at three soil depths (0–15, 15–30, 30–45 cm), the litter and the understory were assessed in sample plots. The results showed that the total amount of carbon stored by Eldar pine (36.8 Mg/hm2) was higher than those stored by the trees in the other three plantations, which were 23.7, 10.0, and 9.6 Mg/hm2 for Arizona cypress, mulberry and black locust plantations, respectively. For all the species, the above-ground biomass accumulations were higher than those of the below-ground. The root mass fractions of the deciduous were larger than those of the coniferous. Accordingly, the results indicate that the potential carbon storages of the coniferous were higher than those of the deciduous in arid regions.

Early differentiation in biomass production and carbon sequestration of white poplar and its two hybrids in Central Iran

We assessed the potential of white poplar（Populus alba L.） and its inter-sectional hybridization with euphrates poplar（P. euphratica Oliv.） for carbon storage and sequestration in central Iran. Trials were established at planting density of 2,500 trees per hectare in block randomized design with three replicates. After 6 years, we measured the above-ground biomass of tree components（trunk, branch, bark, twig and leaf）, and assessed soil carbon at three depths. P. alba 9 euphratica plantation stored significantly more carbon（22.3 t ha-1） than P. alba（16.7 t ha-1） and P. euphratica 9 alba（13.1 t ha-1）.Most of the carbon was accumulated in the above-ground biomass（61.1 % in P. alba, 72.4 % in P. alba 9 euphratica and 56.0 % in P. euphratica 9 alba）. There was no significant difference in soil carbon storage. Also, biomass allocation was different between white poplar P. alba and its inter-sectional hybridization. Therefore, there was a yield difference due to genomic imprinting, which increased the possibility that paternally and maternally inherited wood production alleles would be differentially expressed in the new crossing.