An allometric smoothing function to describe the relation between otolith and somatic growth over the lifespan of walleye pollock (Theragra chalcogramma)

We propose a new equation to describe the relation between otolith length (OL) and somatic length (fork length [FL]) of fish for the entire lifespan of the fish. The equation was developed by applying a mathematical smoothing method based on an allometric equation with a constant term for walleye pollock (Theragra chalcogramma) —a species that shows an extended longevity (>20 years). The most appropriate equation for defining the relation between OL and FL was a four-phase allometric smoothing function with three inflection points. The inflection points correspond to the timing of settlement of walleye pollock, changes in sexual maturity, and direction of otolith growth. Allometric smoothing functions describing the relation between short otolith radius and FL, long otolith radius and FL, and FL and body weight were also developed. The proposed allometric smoothing functions cover the entire lifespan of walleye pollock. We term these equations “allometric smoothing functions for otolith and somatic growth over the lifespan of walleye pollock.

Potensi Simpanan Karbon Di Atas Permukaan Tanah Tegakan Acacia Nilotica L. (Willd) Ex. Del. Di Taman Nasional Baluran, Jawa Timur

Acacia nilotica is an invasive species which is difficult to eradicate up to present. A. nilotica is a fast growing species of savanna tree, and therefore is supposed probably to have relatively high biomass and carbon content. The objective of this research was to develop allometric equation of biomass and estimating the carbon storage potential in A. nilotica stand in Baluran National Park. This research used destructive method on 9 sample trees to construct allometric equation. For measuring biomass potency, vegetation analysis was conducted using 3 plots, measuring 100 m x 100 m each on the basis of A nilotica stand density categorization (high, medium, and low). For obtaining data of carbon potency, biomass value was multiplied with 0,47. Research results show that the selected allometric equation for tree total is W=0,34 D1,97 with R2of 98,4. Average biomass potency was as large as 25 tons/ha. Average carbon potency was 11,92 ton/ha. Management of A. niloticain Baluran National Park, in moderate and low density stand can be in the form of clear cutting, whereas high density stand can be maintained for carbon sequestration and utilization by the people community for supplying seeds, livestock feeds, firewood or charcoal briquette

Species Specific Allometric Model for Biomass Estimation of Polyscias fulva Harms in Tumata Chirecha Agroforestry Gedeo Zone of Ethiopia: Implication for Sustainable Management and Climatic Change Mitigation

Species specific allometric equation is important for accurate net aboveground biomass estimation and quantifying carbon stock in living tree biomass of terrestrial ecosystems. This study was undertaken to develop species-specific allometric equation non-destructively of the Polyscias fulva Harms Tumata Chirecha KPA agroforestry Gedeo Zone. Currently, like that of most Ethiopian agroforestry such model did not exist for this particular study area. The data was taken from 12 individuals with DBH class intervals in between (20-60 cm). Preferential sampling method was used to collect data from four rectangular plots each with a 10m*20m. The allometric equations were developed by relating tree component biomass to DBH or basal diameter. And the post analysis was highly significant (P > 0.000) fit for linear models for all the components and displayed minimal bias. It had a mean total biomass of 323.42 kg. It is understood that previously published allometric model in agroforestry reveal errors of over estimation of biomass, and propose the new equations to be used in the future for the selected four indigenous species. And it would create an opportunities for sustainable management of agroforestry and to mitigate climatic change through increasing the household income. Keywords: Allometric equation, Biomass, DBH, Gedeo Zone, Non- destructive Tumata Chirecha KP

Species Specific Allometric Model for Biomass Estimation of Millettia ferruginea (Hochst) Bak. in Tumata Chirecha Agroforestry Gedeo Zone: Implication for Climatic Change Mitigation

Species specific allometric equation is important for accurate net aboveground biomass estimation and quantifying carbon stock in living tree biomass of terrestrial ecosystems. This study was undertaken to develop species-specific allometric equation non-destructively of the Millettia ferruginea in Tumata Chirecha KPA agroforestry Gedeo Zone. Currently, like that of most Ethiopian agroforestry such model did not exist for this particular species and study area. The data was taken from 12 individuals with DBH class intervals in between (20-60 cm). Preferential sampling method was used to collect data from four rectangular plots each with a 10m*20m. The allometric equations were developed by relating tree component biomass to DBH or basal diameter. And the post analysis was highly significant (P > 0.000) fit for linear models for all the components and displayed minimal bias. It had a mean total biomass of 599.36 kg. It is understood that previously published allometric model in agroforestry reveal errors of over estimation of biomass, and propose the new equations to be used in the future for the selected four indigenous species. And it would create an opportunities for sustainable management of agroforestry and to mitigate climatic change through increasing the household income. Keywords: Allometric equation, Biomass, DBH, Non-destructive, Tumata Chirecha KPA

Allometric Equation for Biomass Estimation of Cordia africana Lam. in Tumata Chirecha Agroforestry Gedeo Zone: Implication for Sustainable Management and Climatic Change Mitigation

Species specific allometric equation is important for accurate net aboveground biomass estimation and quantifying carbon stock in living tree biomass of terrestrial ecosystems. This study was undertaken to develop species-specific allometric equation non-destructively of the Cordia africana Lam in Tumata Chirecha KPA agroforestry Gedeo Zone. Currently, like that of most Ethiopian agroforestry such model did not exist for this particular study area. The data was taken from 12 individuals with DBH class intervals in between (20-60 cm). Preferential sampling method was used to collect data from four rectangular plots each with a 10m*20m. The allometric equations were developed by relating tree component biomass to DBH or basal diameter. And the post analysis was highly significant (P > 0.000) fit for linear models for all the components and displayed minimal bias. Cordia africana Lam had a mean total biomass of 442.02 kg. It is understood that previously published general allometric model in agroforestry reveal errors of over estimation of biomass, and propose the new equations to be used in the future for the selected indigenous species. And it would create an opportunities for sustainable management of agroforestry and to mitigate climatic change through increasing the household income. Keywords: Allometric equation, Biomass, Gedeo Zone, Tumata Chirecha KP

Development of allometric equation for biomass of rubber tree (Hevea brasilliensis) saplings

Carbon is sequestered by plant through photosynthesis and stored as biomass in different parts of the tree including stems, branches, leaves and roots. The objective of this study is to determine the biomass in five different growth stages of rubber tree saplings and to develop the allometric equation for biomass estimation. Biomass of rubber tree saplings was measured for the growth stages of 45, 90, 135, 180 and 225 days with total number of samples used was 650 saplings. Biomass was determined by weighing the constant dry weight of the samples. Four candidate models were selected and evaluated and Model 4 appeared to be the best allometric equations for biomass estimation of rubber tree saplings in the form of log10 W = 0.184 + 0.007 log10 D + 0.705 log10 HT + 0.002 log10 AG, (R2=0.96). The allometric equation developed in this study is useful for the estimations of biomass in rubber tree saplings

Combined Effects Of Body Size Food Concentration And Season On Physiology Of Mytilus-Edulis

Multivariate experiments are used to study the effects of body size, food concentration, and season on the oxygen consumption, ammonia excretion, food assimilation efficiency and filtration rate of Mytilus edulis adults. Food concentrations and season affect both the intercept and the slope of the allometric equation describing oxygen uptake as a function of body size. Multiple regression and response surface techniques are used to describe and illustrate the complex relationship between metabolic rate, ration, season and the body size of M. edulis. Filtration rate has a relatively low weight exponent Q> = 038) and the intercept for the allometric equation is not significantly affected by food concentration, season or acclimation temperatures between 5 and 20 °C. Food assimilation efficiency declines exponentially with increasing food concentration and is dependent on body size at high food levels. The rate of ammonia excretion shows a similar seasonal cycle to that of oxygen consumption. They are both minimal in the autumn/winter and reach a maximum in the spring /summer

Carbon assessment for cocoa cropping systems in Lampung, Indonesia

Cocoa (Theobroma cacao L.) production plays a key role in the economics of Indonesia, the world’s fourth largest cocoa bean producing country. With more than 1.6 million hectares of land planted with cocoa, small improvements in emissions efficiencies or carbon sequestration opportunities can have a relatively large mitigating effect on emissions from agroforestry and land use. The carbon assessment in Lampung, Sumatra was done to evaluate environmental impacts of cocoa as a commodity through estimation of carbon stock and carbon footprint, GHG emissions during the cultivation of cocoa in different cropping systems. Segmentation of cropping systems along density of intercropping, inputs use intensity and residue management practices identify opportunities for climate smart practices tailored to each segment

Allometric Equation for Estimating Energy Production of Eucalyptus urophylla in Dryland Ecosystems at East Nusa Tenggara

A precise and accurate energy production quantification, particularly at the individual tree level is needed to understand the potential contribution of eucalyptus plantations to renewable energy development. However, measuring energy storage with a destructive method is inefficient because it requires a large amount of resources. The development of allometric equations is a realistic solution to solve this problem as it facilitates the efficient estimation of energy production from trees. Therefore, this study aims to develop an allometric equation for estimating the energy production of Eucalyptus urophylla in dryland ecosystems in East Nusa Tenggara. The destructive sampling was carried out on 25 sample trees which are evenly distributed from small to large dimensions, while the calorific value of each tree component was analyzed using the bomb calorimeter method. Furthermore, the energy production of each tree was counted by multiplying the calorific value with the total biomass accumulation. To develop an allometric equation, the analysis of regression was applied using several independent variables, such as diameter at breast height (D), combined squared diameter of breast and tree height (D2H), as well as D and H separately. The results showed that the energy production of E. urophylla at the study site varied from 252.56 to 7,813.30 MJ tree-1 with more than 90% accumulated in the stem, followed by foliage (4.62%) and branches (4.05%). The higher the tree dimension, the greater the energy production. Moreover, the equation lnŶ = lna + b.lnD + c.lnH was the best allometric model to estimate energy production with an accuracy of 95.2%. Based on the results, the allometric equation provides an accurate estimation of energy production in E. urophylla