Growth Characteristics, Biomass and Chlorophyll Fluorescence Variation of Garhwal Himalaya’s Fodder and Fuel Wood Tree Species at the Nursery Stage

Fodder and fuel wood deficiency in the Himalayan region is well recognized. Rural inhabitants are exploiting these forest resources for their livelihood for generations which leads to severe deforestation. The aim of this study was to identify the fast growing fodder and fuel wood tree species of Garhwal Himalayas at nursery stage with wider relevance and great potential for extensive afforestation programmes. Seed of Bauhinia purpurea L., Bauhinia retusa Roxb., Bauhinia variegate L., Celtis australis L., Ficus nemoralis Wall., Ficus roxburghii Wall., Grewia optiva Drummond, Leucaena leucocephala (Lam.) de Wit, Melia azedarach L., Ougeinia oojeinensis (Roxb.) Hochr., Quercus leucotrichophora A. Camus, Terminalia alata Heyne ex Roth. and Toona ciliate M. Roem. were collected from the superior trees and seedlings were raised. After one year and one month of establishment at the nursery, the growth characteristics, biomass and chlorophyll fluorescence (dark-adopted Fv/Fm) of each species were also recorded. G. optiva had shown the highest growth in terms of height, basal diameter increment and number of branches, while production of leaves was more on O. oojeinensis. Biomass and chlorophyll fluorescence (maximum quantum yield or photochemical efficiency of PSII) was found highest in Q. leucotrichophora which indicates photosynthetically this species was most active among the studied fodder and fuel wood tree species. The information in this communication could be utilized for developing various conservation and sustainable strategies in the Garhwal Himalayas to mitigate

Cluster planting impact on cotton growth, yield and biomass accumulation in an arid region oasis

The cluster planting pattern （3 plants per hole） for cotton （Gossypium hirsutum L.） may increase economic yield over those of the traditional planting pattern （1 plant per hole） in arid regions of China. This increase in yield depends on either increased biomass production or greater partitioning to fruit. This study was conducted to determine whether differences in biomass accumulation or partitioning to reproductive growth contributed to higher yield in the cluster planting pattern compared with the traditional one. Growth parameters, biomass accumulation, crop growth rate and partitioning between cluster planting pattern and traditional planting pattern was compared in northwest of China. The biomass production and partitioning in cluster planting plot was higher than in traditional planting one. Biomass accumulation was faster early in the clustered treatment, and it was also higher at harvest time. Total dry matter production per unit area was significantly higher than in the traditional planting. On a per plant basis, dry matter accumulation was faster and total biomass production was significantly higher in the cluster planting pattern. Numbers of sympodia and boll sizes were also larger, indicating that facilitation among plants was promoting crop yield. The increase in yield in the cluster planting treatment occurred through increased partitioning of dry matter to fruits than in the traditional planting pattern, resulting in more bolls and increased lint yield in arid regions.

Changes in gas exchange,root growth,and biomass accumulation of Platycladus orientalis seedlings colonized by Serendipita indica

Serendipita indica(formerly known as Piriformospora indica),a root endophytic fungus,exhibits multiple functions in some agricultural,horticultural,and medicinal plant species.We studied colonization of the roots of Platycladus orientalis,a forest tree species,by S.indica to improve the quality of the seedlings in seedbeds and survival rates in sylviculture.At 20 days after inoculation,S.indica colonized the root cortex of P.orientalis seedlings.Root colonization by S.indica significantly increased net CO2 assimilation,light use efficiency,and biomass accumulation by both roots and shoots,whereas it did not affect the biomass allocation between roots and shoots.In addition,the symbiosis significantly increased root total length,surface area,and volume.In view of the two specific traits of S.indica,i.e.,axenic culture and wide colonization in plants,the fungus might be used for improving quality of P.orientalis seedlings and increasing their survival after transplanting.

Efficiency of Bio-Fertilizing as One of the Natural Alternatives to Improve the Growth of Khaya senegalensis and Swietenia mahagoni Trees and for Sustainability

A field experiment was carried out at Ismailia Research Station, Ismailia Governorate from 2020-2022 to improve the growth of Khaya senegalensis and Swietenia mahagoni by using a combination of mineral fertilizer (NPK) and biological fertilizer (Azotobacter chroococcum, Bacillus megatherium, and Bacillus circulant) as recommended dose under new sandy soils conditions. Split plot designed with four treatments (Control, (50% Mineral fertilizer (M.) + 50% Biological fertilizer (Bio.)), 100% M. and 100% Bio.) of each species. Vegetative growth, leaf area, tree biomass, stored carbon, basal area, tree volume, and in the soil both of microbial account and mineral content were determined. The experimental results showed no significant differences between studied species among the most studied parameters except for Khaya senegalensis which gave the highest significant difference in root biomass and below-stored carbon than Swietenia mahagoni. Evidently, the highest significant growth parameters were 100% mineral fertilizer followed by (50% M. + 50% Bio.) as compared with control. No significant difference between 100% M. and (50% M. + 50% Bio.) of shoot dry biomass (15.19 and 12.02 kg, respectively) and above-stored carbon (0.28 and 0.22 Mt, respectively). Microbial account and mineral content in soil were improved after cultivation of tree species compared to before planting and control, especially with 50% mineral fertilizer and 50% bio-fertilizer treatment. In conclusion, a treatment containing 50% mineral fertilizer and 50% bio-fertilizer has led to the ideal Khaya senegalensis and Swietenia mahagoni growth in sandy soil for cheaper and sustainable.

Comparisons of Yield and Growth Behaviors of Hybrid Rice Under Different Nitrogen Management Methods in Tropical and Subtropical Environments

To compare the grain yield and growth behaviors of hybrid rice, field experiments were conducted in a subtropical environment in Changsha, Hunan Province, China, and in two tropical environments in Gazipur and Habiganj in Bangladesh during 2009 to 2011. Three hybrid rice cultivars were grown under three nitrogen （N） management treatments in each experiment. The results showed that grain yield was significantly affected by locations, N treatments and their interaction but not by cultivars. Changsha produced 8-58% higher grain yields than Bangladesh locations. Sink size （spikelet number per unit land area） was responsible for these yield differences. Larger panicle size （spikelet number per panicle） contributed to greater sink size in Changsha. Aboveground total biomass was greater in Changsha than in Bangladesh locations, whereas harvest index was higher in Bangladesh locations than in Changsha. Crop growth rate （CGR） was greater at Changsha than Bangladesh locations during vegetative phase, while the difference was relatively small and not consistent during the later growth phases. Higher leaf area index and leaf area duration were partly responsible for the greater CGR in Changsha. Real-time N management （RTNM） produced lower grain yields than fixed-time N management in more than half of the experiments. Our study suggested that further improvement in rice yield in the tropical environments similar to those of Bangladesh will depend mainly on the ability to increase panicle size as well as CGR during vegetative phase, and the chlorophyll meter threshold value used in RTNM needs to be modified according to environmental conditions and cultivar characteristics to achieve a desirable grain yield.

Live above-and belowground biomass of a Mozambican evergreen forest:a comparison of estimates based on regression equations and biomass expansion factors

Background： Biomass regression equations are claimed to yield the most accurate biomass estimates than biomass expansion factors （BEFs）. Yet, national and regional biomass estimates are generally calculated based on BEFs, especially when using national forest inventory data. Comparison of regression equations based and BEF-based biomass estimates are scarce. Thus, this study was intended to compare these two commonly used methods for estimating tree and forest biomass with regard to errors and biases. Methods： The data were collected in 2012 and 2014. In 2012, a two-phase sampling design was used to fit tree component biomass regression models and determine tree BEFs. In 2014, additional trees were felled outside sampling plots to estimate the biases associated with regression equation based and BEF-based biomass estimates; those estimates were then compared in terms of the following sources of error： plot selection and variability, biomass model, model parameter estimates, and residual variability around model prediction. Results： The regression equation based below-, aboveground and whole tree biomass stocks were, approximately, 7.7, 8.5 and 8.3 % larger than the BEF-based ones. For the whole tree biomass stock, the percentage of the total error attributed to first phase （random plot selection and variability） was 90 and 88 % for regression- and BEF-based estimates, respectively, being the remaining attributed to biomass models （regression and BEF models, respectively）. The percent bias of regression equation based and BEF-based biomass estimates for the whole tree biomass stock were -2.7 and 5.4 %, respectively. The errors due to model parameter estimates, those due to residual variability around model prediction, and the percentage of the total error attributed to biomass model were larger for BEF models （than for regression models）, except for stem and stem wood components. Conclusions＂ The regression equation based biomass stocks were found to be slightly larger, associated with relatively smaller errors and least biased than the BEF-based ones. For stem and stem wood, the percentages of their total errors （as total variance） attributed to BEF model were considerably smaller than those attributed to biomass regression equations.

Implications of Papyrus (<i>Cyperus papyrus</i>L.) Biomass Harvesting on Nutrient Regulation in Nyando Floodplain Wetland, Lake Victoria, Kenya

Harvesting of papyrus biomass plays a significant role in regulating ecosystem services of which one of them is nutrient uptake and cycling. Despite Lake Victoria’s wetlands being important, little is understood about its role in nutrient uptake and removal. Although there have been studies done in these wetlands, there is inadequate understanding on the implication of unselective biomass harvesting on the water quality of Lake Vitoria. At the same time, these wetlands are threatened by livelihood-related pressures which are driven by extreme hydrological regimes. This study focused on Nyando floodplain wetland located in the Eastern part of the shores of Lake Victoria which is a lifeline to many rural communities living around the lake. Papyrus biomass harvesting was assessed in two study sites of Nyando wetland and at different seasons in order to determine its implication on nutrient regulating services. Participatory tools, field survey, observation, field measurements and laboratory analysis were used. Harvesting of papyrus removed 530.6 Kg N/g DM/ha/day and 97 Kg P/g DM/ha/day in Ogenya while 771.2 Kg N/g DM/ha/day and 109.2 Kg P/g DM/ha/day were removed in Wasare. However, addition of nutrients to the wetland may lead to the problem of eutrophication especially at the site where interaction of wetland and lake water occurs. Understanding the role of papyrus harvesting patterns is crucial for better planning and management of this complex resource in a changing environment.

Growth Characteristics and Resource Evaluation of Sebastes schlegelii in Zhangzidao Artificial Reef Area

[Objective]The paper was to formulate catchable size and total allowable catch of Sebastes schlegelii in Zhangzidao artificial reef area.[Method]Based on analysis of length-weight formula,body length and weight growth equations,and instantaneous mortality rate,the inflection age and critical age of weight growth were calculated,and the biomass of S.schlegelii in Zhangzidao artificial reef area was estimated.[Result]The growth equation of body length was Lt=412.5×[1-e^-0.21（t＋0.65）]and the growth equation of body weight was Wt=1 734.2×[1-e^-0.21（t＋0.65）]^2.92.The inflection age and critical age for weight growth of S.schlegelii were 4.45 and 4.82 a,respectively.The biomass in Zhangzidao artificial reef area was about 456.8 t.[Conclusion]For S.schlegelii flock in Zhangzidao artificial reef area,the catchable length was about 271.2-281.7 mm,the catchable weight as about 509.4-569.5 g,and the total allowable catch was about 60.43 t.

Effects of sawdust soil amendment on the soil, growth and yield of Solanum esculentum Linn. in waste engine oil-polluted soil

This study investigated the effects of sawdust as a soil amendment on certain growth parameters of Solanum esculentum Linn. grown in soil polluted with various concentrations of waste engine oil, and changes in the physicochemical proper- ties of the soil. The purpose was to assess the soil remediation potentials of sawdust in waste engine oil-polluted soil. The experiment was divided into three regimes： control （air-dried soil without waste engine oil and with clean sawdust）, pol- luted （waste engine oil-contaminated soil）, and amended （oil-polluted soil amended with sawdust）. Enough 3-kg soil samples were sieved and air-dried to prepare five treatment levels of waste engine oil-contaminated soil （30 mL, 1%; 60 mL, 2%; 90 mL, 3%; 120 mL, 4%; and 150 mL, 5%）, as well as five additional treatment levels （the same amounts ofoil contamination） in soil amended with sawdust. The treatment levels were replicated five times in a completely randomized design. A nursery bed was planted with a hybrid tomato variety （Roma V F） obtained from National Horticultural Research Institute （NIHORT） in Ibadan, Nigeria. During the maturation period, the growth parameters such as plant height, number of leaves, and number of branches per plant were determined and then the harvested plants were oven dried at 70 ℃for 48 hours to determine their dry weights. The effects of the sawdust amendment on the soil were assessed by determining the soil pH （glass electrode pH meter）, total nitrogen （Kjeldahl method）, total phosphorus （Bray-1 solution）, and potassium （on the leacheate by a flame photometer）. Chromium, lead, and cadmium contents were determined using an atomic absorption spectrophotometer. Analysis of variance and a Duncan multiple-range test were employed to test significant differences in the soil properties of the three regimes. The growth performance ofSolanum esculentum Linn. in the amended regime （soil with sawdust） at the 150-mL waste engine oil-contamination level was significantly higher than in the polluted regime （soil without sawdust）. After plant harvest, the pH of the soil was shown to be clearly affected by the addition of waste engine oil. The control soil （air-dried only, no sawdust, no oil） had the highest pH value, 6.60, which was significantly different from the pH values at other levels of waste engine oil contamination. However, when amended with sawdust, the control soil had a significantly lower pH value than the unamended control soil. This study further demonstrates that sawdust has the potential of amending waste engine oil-contaminated soil for increasing tomato growth performance because it is capable of increasing the soil nutrient content and reducing the soil total hydrocarbon content.

Biomass allocation and assimilation efficiency of natural Tilia amurensis samplings in response to different light regimes

Biomass allocation and assimilation efficiency of natural Amour linden (Tilia amurensis) samplings in different light regimes were analyzed in the paper. The results showed that shoot increment of samplings in gap was the highest and that of samplings under canopy was the least. Samplings in gap expressed apical dominance strongly but samplings in full sun and under canopy behaved intensive branching. Lateral competition or moderate shading was favored to bole construction. The patters of biomass allocation of samplings in different light environment were rather similar. The biomass translocated to stem was more than that to other organs, and about one half of photosynthate was used to support leaf turn over. On the contrary, photosynthates of samplings in full sun were mostly consumed in leaves bearing and energy balancing. The carbon assimilation for leaves of samplings in gap was the most efficient, and more carbons were fixed and translocated to non-photosynthetic organs, especially to stemwood.

Identification of Growth-promoting Bacteria from Rhizosphere of Pastures and Their Effects on Growth of Lotus corniculatus L.

[Objectives] This study was conducted to explore the interaction between nitrogen-fixing and phosphate-solubilizing strains and the optimal combination of different functional strains,in order to provide a theoretical basis for the development of PGPR compound fertilizers suitable for local environment.[Methods] In this study,16S rDNA gene sequence analysis was used to identify fast-growing and competitive strains from pasture nodules and rhizosphere soils in Guizhou Province,and three representative Rhizobia and phosphorus-solubilizing bacteria were chosen for the test of bacterial combination when reducing 50% of nitrogen and 30% of phosphorus.The effects of different strain combinations on the plant height,root length,aboveground and underground biomass of Lotus corniculatus L.were investigated,and the total nitrogen and total phosphorus contents of the plants were determined.[Results] The mixed bacterial agents could promote the increase of root biomass,and the effects of A1,A3,B3 and C3 were the most obvious.The fresh weight and dry weight of the roots of L.corniculatus increased by 30.35%-168.45% and 26.43%-180.00%,respectively,and A3,B3,B2 and C3 had the best effects.The total phosphorus content of the plants increased by 12.79%-55.25% compared with the CK2;and most of the bacterial agents with significant growth-promoting effects showed decreased total nitrogen contents,while those with non-significant growth-promoting effects showed significantly-increased total nitrogen contents,which were not as much as the CK1.Comprehensively,the most productive combination was C3,namely R27-2 Rhinohizobium fredii and P33-3 Stenotrophomonas rhizophila.[Conclusions] This study can provide a theoretical basis for the production and promotion of bacterial fertilizers.

Impact of Sugar Industrial Treated Effluent on the Growth Factor in Sugarcane—Cuddalore, India

The present study focused on evaluating the impact of application of sugar industry treated wastewater effluent on Sugarcane growth comparing at two experimental farms, one irrigated with the effluent and the other with bore well water, over a period of 11 months (March 2010 to January 2011).The result indicated a significant increase in growth pattern, plant height, shoot diameter, number of leaves and nodes, and biomass of the saplings that was irrigated with the effluents compared to that irrigated with bore well water. The growth parameters showed close relationship with the nutrient contents of treated industrial effluent and bore well water, the former being characterized by relatively higher pH, electrical conductivity (μs/cm), total suspended solids (TSS), sulphate, biochemical oxygen demand, chemical oxygen demand, nitrate and phosphate, and heavy metals—Cu, Pb, Cd, Zn and Mn (mg/l) compared to that of bore well water, indicating profound influence of nutrient rich sugar industry effluent on the plant growth. Higher biomass in sugarcane saplings resulted with irrigation of the effluents compared to that irrigated with the bore well water.

Analysis and Optimisation of Halomonas Growth Factors Based on PCA and RSM

The biomass of petroleum-degrading bacteria, such as Halomonas spp., is crucial to the alleviation of severe oil spills through bioremediation. In this paper, the bacterium(HDMP1) was isolated and identified. Growth factors were analysed and optimised through the single-factor experiments, the factor analysis(FA), the principal component analysis(PCA), and the response surface methodology(RSM). Results indicated that HDMP1 was identified as genus Halomonas. In the single-factor experiments, the range of suitable growth conditions for HDMP1 covered: a salt concentration of 2%-4%, a medium pH value of approximately 9, an inoculum concentration of 1.0%, a substrate concentration of 1.0%-1.4%, and a rotation rate of 140 r/min. The evaluation by FA and PCA indicated that three significant growth factors were the salt concentration, the pH value, and the rotation rate. A maximum biomass of HDMP1 was obtained under the conditions covering a salt concentration of 3.5%, a medium pH of 8, and a rotation rate of 151 r/min by optimization.

SEASONAL RHYTHM OF ABOVEGROUND BIOMASS——THE CALAMAGROSTIS ANGUSTIFOLIAGRASSLAND IN SANJIANG PLAIN

In this paper, the seasonal rhythms of the above grassland biomass of the two main types of the Calamagrostis angustifolia grasslands, the Calamagrostis angustifolia meadow and the Calamagrostis angustifolia + Carex schmidilu swamp meadow, were reported. The simulation technique was employed to described the dynamic process. In the end, the absolute growth rate and the relative growth rate of abovcground biomass of the two communities were approached in the light of the growth analysis method.

Growth and Yield Responses of Switchgrass Ecotypes to Temperature

Varietal differences of switchgrass in growth and development, biomass yield and partitioning in response to temperature are not well documented. A study was conducted to quantify the effect of temperature on growth, development, and feedstock quality of switchgrass cultivars, and to determine differences between upland and lowland switchgrass. Two lowland (“Alamo” and “Kanlow”) and two upland (“Caddo” and “Cave-in-Rock”) cultivars of switchgrass were grown in pots filled with pure, fine sand in growth chambers. Four different temperature treatments of 23℃/15℃, 28℃/20℃, 33℃/25℃, and 38℃/30℃ with 14/10 hours day/night were imposed at four leaf stage. High temperature significantly decreased the biomass yield across all cultivars. Stem elongation rate (SER) and leaf elongation rate (LER) decreased at the highest temperature treatment but lowland cultivars had significantly higher SER and LER across the temperature treatments. Upland cultivars produced more tillers across the temperature treatment. Both shoot/root and leaf/stem ratios increased under the highest temperature in all cultivars, but upland cultivars partitioned more to the leaf and root at higher temperature. Concentration of cellulose decreased at the highest temperature but temperature had no effect on lignin concentration of leaf and stem biomass. In conclusion, although none of the cultivars studied showed strong tolerance to high temperature, differences were observed for many traits of switchgrass in response to temperature.

The Biomass Dosage Influences the Effects of Diethyl Aminoethyl Hexanoate on Micropropagation of Echinacea purpurea (L.) Moench

The plant growth regulator diethyl aminoethyl hexanoate (DA-6) has proved highly effective on micropropagation of the medicinal plant purple coneflower (Echinacea purpurea (L.) Moench), however, sharp variation of the effects existed among explants in the same treatment, making the application of DA-6 in micropropagation difficult. In order to clarify factors that influencing the treating results of DA-6, explants with different biomass dosage were prepared and inoculated onto medium supplemented with different concentrations of DA-6. It was found that among the three kinds of biomass dosage explants, the lowest biomass explants required the lowest concentration of DA-6, and the highest biomass explants required the highest concentration of DA-6 for the best results on adventitious buds regeneration. Similar results were obtained when regenerated buds of three different biomass dosages were cultured. It could be concluded from the above experimental results that for achieving better DA-6 application results, the concentration of DA-6 should be determined not only by the types but also by the biomass dosage of the explants. The present finding might help to improve the micropropagation efficiency in E. purpurea, and might be applicable for other species

A theoretical analysis of the growth process of an organism and its dependence on various allometric relations

A new mathematical model regarding the growth process of an organism is proposed, based on the role of surplus power (i.e. power intake minus metabolic cost) and having an allometric dependence on mass. Considering its use in growth, a differential equation has been formed, similar to the von Bertalanffy growth function (VBGF). The time dependence of mass and growth rate, obtained from this equation, has been shown graphically to illustrate the roles played by scaling exponents and other parameters. Concepts of optimum mass, saturation mass and the mass corresponding to the highest growth rate have been discussed under the proposed theoretical framework. Information regarding the dependence of effective growth duration on various parameters has been found graphically. The time of occurrence of the highest growth rate and its dependence on various parameters have been explored graphically. A new parameter (ρ) has been defined, which determines the availability of surplus power at different stages of the growth process of an organism. Depending on its value, there can be three distinctly different modes of growth phenomenon, reflected in the change of surplus power with time. The variations of growth and reproduction efficiencies with time and mass have been shown for different values of the scaling exponent. The limitation regarding the practical measurement of growth rate has been discussed using the present model. Some aspects of length-biomass allometry have been explored theoretically and the results have been depicted graphically.

中龄林修枝对杉木林生长和材种结构的影响

为培育杉木大径级无节柱材,探讨修枝对杉木人工林生长和材种结构的影响,选择17年生中龄林,设置修枝与不修枝处理试验,20 a后调查中龄林修枝处理对杉木人工林生长和材种结构影响。结果表明:修枝后的前两年,修枝处理显著提高了杉木人工林的胸径年生长量(P<0.05),对树高、林分蓄积量年生长量没有显著影响,随后修枝处理对杉木人工林生长的影响逐渐减弱。中龄林修枝处理20 a对杉木人工林的胸径、树高、林分蓄积量和总生物量均没有显著影响,但显著提高了杉木人工林干生物量分配比例(P<0.05),显著降低了叶生物量分配比例(P<0.05)。中龄林修枝处理20 a显著提高了杉木人工林大径材出材率(P<0.05),有利于杉木人工林大径无节柱材培育。

基于森林资源清查资料的盈江县森林生物量和生长量分析

为确定盈江县森林碳储量和碳汇潜力的变化特征及其影响因子,以便更好地分析盈江县森林生物量和生长量。基于盈江县2012年和2017年森林资源清查数据,利用生物量换算因子连续函数法和异速生长方程,评估盈江县森林碳储量和碳汇潜力的变化特征及其影响因子。结果显示:(1)盈江县森林生物量储量丰富,达85.55 t/hm^(2)。其中:栎类林最大,为168.3 t/hm^(2);核桃林最低,为7.10 t/hm^(2)。(2)不同林龄林分生物量差异较大,近熟林最高,其次分别为中龄林、成熟林、过熟林、幼龄林。(3)常绿阔叶林的林分生长量最大,其次是落叶阔叶林和针叶林。结果表明:盈江县森林生物量储量丰富且以阔叶林为主;林龄和年均气温是影响林分生长和生物量的主要因素。

香合欢幼苗生长性状与生物量分布的相关性分析

为了解香合欢苗木生长性状与生物量之间的相互关系,以1年生香合欢幼苗为研究对象,对苗高、地径、主根长和侧根数4个生长性状及各组分生物量进行测定和计算,运用相关性分析和回归分析剔除对生物量影响不大的性状,在此基础上构建回归模型。结果表明:香合欢幼苗生长性状变异水平居中,可作为良好的变异研究对象;同时根冠比具有较高的变异系数(接近或超过20%),说明个体间的差异较大,具有从中选择生长表现优异个体的优势;主根长与其各生物量之间的相关性最小,而苗高、地径和侧根数与各生物量之间的相关性较高,均达到极显著相关。将相关性极显著的各组分生物量和相应的形态指标进行回归分析发现,其拟合优度较好,其中,拟合优度较好指标为苗高(R2=0.706)和地径(R2=0.580)。经过筛选,得出2个最优回归模型,分别为地上生物量与苗高的“J”型增长曲线模型(ln EAB=0.075H–0.310)、总生物量与地径的一元线性回归模型(EB=1.472H–1.769);这2个模型精度较高,符合实际应用需求,说明香合欢苗木的生物量可以通过与其相关性较高的生长性状指标进行回归估算获得。