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A study was conducted on the changes in sea surface temperature (SST) on the southwestern shelf of the Crimea between 2000 and 2020. The equations of trends in the change of SST were found. It is shown that the following three periods can be distinguished according to the nature of changes in the average annual sea temperature: 2000 - 2007, 2008-2013 and 2014 - 2020. The influence of changes in the average annual SST on the development of pelagic fish of the cold-water complex was considered (using the example of the Black Sea sprat). Changes in the main parameters of the populations and their relationship with the change in the average annual SST were determined. It was found that the increase in sea temperature negatively affected the development of the sprat population, and the average age of the population decreased by 1.3 times. In general, the population was rejuvenated, and the average size and weight of individuals decreased.

A study of changes in sea surface temperature (SST) on the southwestern shelf of Crimea in 2000–2020 has been conducted. The equations of trends in the change in SST are found. It is shown that, according to the nature of changes in the average annual sea temperature, three periods can be distinguished: 2000–2007, 2008–2013, and 2014–2020. The influence of changes in the average annual SST on the development of pelagic fish of the cold-water complex (using the example of the Black Sea sprat) is considered. Changes in the main parameters of populations and their relationship with the change in the average annual SST are found. It is found that the observed increase in sea temperature negatively affected the development of the sprat population; the average age of the population has decreased by 1.3 times. In general, the population has been rejuvenated, and the average size and weight of individuals has decreased. [ABSTRACT FROM AUTHOR]

In the subtropical mountainous area of Huangshan, China, 81 Torreya grandis were selected for research on growth and element distribution, with the aim of providing empirical and theoretical support for the promotion and management of T. grandis. Seven growth equations were constructed for tree height (H) and diameter at breast height (DBH) in age levels 40–2000. The most suitable Korf equation was selected by comparing the R-squared values. With R-squared values of 0.93 and 0.80, the equations H = 33.98 × Exp(−53.56/age0.84) and DBH = 158.48 × Exp(−21.41/age0.55) fit T. grandis growth best, respectively. The results show that T. grandis growth was relatively rapid before the age of 45 and then slowed. Among the carbon (C), nitrogen (N), and phosphorus (P) elements found in different T. grandis organs of the same age, the roots had the lowest C content, the leaves had the highest N content, and the branches had the lowest P content. The roots had the highest C:N and C:P, and the leaves had the highest N:P. The amount of N in the leaves and P in the branches both increased significantly with age, and the N:P ratio indicates that considering only one organ may not accurately indicate T. grandis nutrient limitations. [ABSTRACT FROM AUTHOR]

The influence of the average annual sea surface temperature (SST) on the development of the horse mackerel Trachurus mediterraneus on the southwestern Crimean shelf has been shown. The changes in the main indicators of the population and their relationship with the change in the average annual SST (0.055°С/year) in 2000–2020 have been identified. Against the background of the observed increase in SST in recent years, the state of the horse mackerel population has improved: there has been an increase in the average age and, accordingly, the proportion of larger well-fed individuals, and, in general, the average size and weight of fish. It has been shown that according to the nature of the change in the average annual SST, three periods can be distinguished: 2000−2007, 2008−2013, and 2014−2020. [ABSTRACT FROM AUTHOR]

Abstract: Modelling and simulation of tree growth that is faithful to the living environment and numerically consistent to botanic knowledge are important topics for realistic modelling in computer graphics. The realism factors concerned include the effects of complex environment on tree growth and the reliability of the simulation in botanical research, such as horticulture and agriculture. This paper proposes a new approach, namely, integrated growth modelling, to model virtual trees and simulate their growth by enforcing constraints of environmental resources and tree morphological properties. Morphological properties are integrated into a growth equation with different parameters specified in the simulation, including its sensitivity to light, allocation and usage of received resources and effects on its environment. The growth equation guarantees that the simulation procedure numerically matches the natural growth phenomenon of trees. With this technique, the growth procedures of diverse and realistic trees can also be modelled in different environments, such as resource competition among multiple trees. [ABSTRACT FROM AUTHOR]

This paper on the otolith microstructure analysis of Maurolicus stehmanni presents estimates of the species growth parameters and longevity. The species inhabits the outer shelf and slope of the southern and southeastern Brazilian Exclusive Economic Zone (EEZ). Growth parameters are important for the knowledge of the species' life history and rational management. M. stehmanni constitutes an important link between the initial and final components of the alimentary chain of the open sea ecosystem, being one of the main food items for squids and large pelagic fish. Among the various applied methods those which presented the most coherent values for growth parameters and were best adapted to the von Bertallanfy's equation were: Li= 55mm K= 0.0088/day and to= 5.5 days Maurolicus stehmanni's longevity is of less than one year (around 220 days) and the sagita daily otolith rings are useful for the determination of its age.Este estudo, baseado na análise da microestrutura dos otólitos de Maurolicus stehmanni, apresenta estimativas dos parâmetros de crescimento e longevidade para esta espécie que habita a plataforma externa e o talude da ZEE sul-sudeste do Brasil. Estes parâmetros são importantes para o conhecimento da estratégia de vida da espécie e para o manejo deste recurso, que constitui um importante elo entre os componentes iniciais e finais da teia alimentar no ecossistema de mar aberto, sendo um dos principais itens na dieta das lulas e grandes peixes pelágicos. Dentre os vários métodos aplicados, os valores dos parâmetros de crescimento mais coerentes com a estratégia da espécie e que melhor se ajustaram à equação de von Bertallanfy foram: Li= 55mm K= 0.0088/dia e to= 5.5 dias. A espécie vive cerca de 220 dias e as marcas diárias nos otólitos sagita são apropriadas para a determinação da idade.

Plants, algae, and fungi are essential for nearly all life on earth. Through photosynthesis, plants and algae convert solar energy to chemical energy in the form of organic compounds that sustains essentially all life on earth. In addition, plants and algae convert the carbon dioxide produced by respiring organisms to oxygen that is needed for respiration. Fungi decompose complex organic compounds produced by respiring organisms so that molecules can be recycled in photosynthesis and respiration. Plants, algae, and fungi have one important feature in common, their cells have walls. Expansive growth and its regulation are central to the life and development of plant, algal, and fungal cells, i.e. cells with walls. In recent decades there has been an explosion of information relevant to expansive growth of cells with walls. Mathematical models have been constructed in an attempt to organize and evaluate this information, to gain insight, to evaluate hypotheses, and to assist in the selection and development of new experimental studies. In this article some of the mathematical models constructed to study expansive growth of cells with walls are reviewed. It is nearly impossible to review all relevant research conducted in this area. Instead, the review focuses on the development of mathematical equations that have been used to model expansive growth, morphogenesis, and growth rate regulation of cells with walls. Also, relevant experimental findings are reviewed, conceptual models are presented, and suggestions for future research are proposed. The authors have attempted to provide an overview that is accessible to researchers that are not working in this field. [ABSTRACT FROM AUTHOR]

Healthy vasculature exhibits a hierarchical branching structure in which, on average, vessel radius and length change systematically with branching order. In contrast, tumor vasculature exhibits less hierarchy and more variability in its branching patterns. Although differences in vasculature have been highlighted in the literature, there has been very little quantification of these differences. Fractal analysis is a natural tool for comparing tumor and healthy vasculature, especially because it has already been used extensively to model healthy tissue. In this paper, we provide a fractal analysis of existing vascular data, and we present a new mathematical framework for predicting tumor growth trajectories by coupling: (1) the fractal geometric properties of tumor vascular networks, (2) metabolic properties of tumor cells and host vascular systems, and (3) spatial gradients in resources and metabolic states within the tumor. First, we provide a new analysis for how the mean and variation of scaling exponents for ratios of vessel radii and lengths in tumors differ from healthy tissue. Next, we use these characteristic exponents to predict metabolic rates for tumors. Finally, by combining this analysis with general growth equations based on energetics, we derive universal growth curves that enable us to compare tumor and ontogenetic growth. We also extend these growth equations to include necrotic, quiescent, and proliferative cell states and to predict novel growth dynamics that arise when tumors are treated with drugs. Taken together, this mathematical framework will help to anticipate and understand growth trajectories across tumor types and drug treatments. [ABSTRACT FROM AUTHOR]

Abstract: We perform the analysis of influence of a ‘wall-loosening factor’ (hereafter: WLF) activity in cases of isotropic or anisotropic growth of a plant cell/organ. We further explore a generalized form of the Lockhart/Ortega type of equation and make the ‘extensibility’ (and the yield stress Y) a time and space dependent parameter, able to report on changing (location-dependent) viscoelastic cell wall properties. This procedure results in scalar and tensor equations, which model WLF-mediated isotropic/anisotropic loosening of polymers composing plant cell walls, thereby allowing pressure-driven polymer creep and plant cell expansion growth. An application to six empirical situations, which temporally and spatially vary the amount of WLFs in the cell wall, is anticipated. Combining the resulting explicit formulae with a curve fitting routine provides a new analytical tool that may relate to physiology and biochemistry of the growth process. It is shown, that the regression lines calculated for the derived growth functions perfectly fit () the experimental data. [Copyright &y& Elsevier]

In experimental culture conditions in tanks, the effect of weight ( W: 11-452 g) and temperature ( T: 14-29°C) on the growth rate (SGR, % bw day) and maximum daily food intake (SFR, % bw day) in sharpsnout sea bream ( Diplodus puntazzo) was studied. The possible combined effect of both independent variables ( W and T) was also analyzed by multiple regression analysis, fitting the data to the equation Ln Y = Ln a + b Ln W + cT + dT + eT Ln W. Both SGR and SFR, and therefore feed efficiency (FE = SGR/SFR), were significantly influenced by the interaction between temperature and weight and may be expressed by means of the following equations: Ln SGR = −6.1705 + 0.5809 T − 0.0087 T − 0.0249 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.949; ANOVA P < 0.0001); Ln SFR = −4.8257 + 0.4425 T − 0.0063 T − 0.0163 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.964; ANOVA P < 0.0001).The results suggest that the optimum temperature for SGR and FE ( T and T), and the temperature at which the maximum SFR ( T) is reached, decreases with body weight, in accordance with the equations: T = 33.297 − 1.435 Ln W; T = 29.332 − 1.890 Ln W; and T = 34.941 − 1.304 Ln W, respectively. In this way, T is 28.4, 26.7, and 24.7°C; T is 30.5, 28.9, and 27.1°C and T is 22.9, 20.6, and 18°C for 30, 100 and 400 g body weight, respectively. [ABSTRACT FROM AUTHOR]

Forestry is a large field with a long history and extensive contents consisting of practical recommendations arrived at by trial and error. In contrast, the science of forestry is a new development relying on reasoning to produce the optimal system of forest management aimed at satisfying human needs and preserving nature at the same time (though not at the same place). The presented overview of this science consists of two parts. The first one develops a theory of tree growth and stand dynamics. The second part applies this theory to optimize forest management and suggest practical recommendations. What unites these two parts is a general method of inquiry. It starts with defining one problem, designs two opposing explanations, and then fuses them into a single solution. Hence, the name: the 1-2-1 method. Unlike material variables of process-based models, the explanations employed by the method are abstractions that outline the boundaries embracing all possible solutions. Each explanation in its turn may be subdivided into two opposites until a solution is reached by bringing the opposites together. The 1-2-1 method accounts for any number of variables by arranging them hierarchically into paired groups. Why exactly two explanations? Because each complex problem has two opposite sides, waiting to be uncovered. We may never know how many factors determine tree growth, yet there is one thing as certain as any mathematical proposition: All these factors are of two kinds—those that facilitate growth and those that restrain it. A factor that does neither is not really a factor. The basic positive process of tree growth is uninhibited cell division. Negative processes include, among others, aging and impediments associated with increasing tree size. When these and several other processes are expressed analytically, we get a meaningful and accurate model of tree growth comprising three pairs of opposites arranged in two levels. The model generalizes empirical equations developed in forestry and exposes biological mechanisms that justify the structure of the equations and explain their success. The resulting growth model describes density-independent growth. The complementary process of competition has inter- and intraspecific components. It is shown that to maximize forest productivity interspecific competition has to be minimized while the intraspecific kind optimized. Uniting the growth model with that describing the effect of intraspecific competition produces the growth-density model that solves many questions of forest management. In particular, the model helps to reconcile two main goals of management: (a) maximizing the financial returns from wood products, and (b) preserving forests with all their biodiversity and invaluable ecosystem services. Still, the thrust of this review is not another growth model or management system. The main point is an attempt to make forestry a science by consistent reasoning from first principles such as discreteness of plant biomass, the inverse relationship between average size and number of trees, and the conflict between the biotic potential and environmental resistance. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel numerical methods for the exponential models of growth are proposed. Based on these methods, hybrid predictor–corrector methods are constructed. The hybrid numerical methods can increase the accuracy and the computing speed obviously, as well as enlarge the stability domain greatly. [Copyright &y& Elsevier]

Abstract: Forestry projects under the Clean Development Mechanism (CDM) may provide several benefits for developing countries. Under the current rules, these projects can participate in both timber and carbon markets. Thus, project developers need to know what the optimal forest management design would be to maximize their revenues according to timber and carbon market expectations while at the same time complying with international rules adopted for carbon sequestration projects under the CDM. We developed Carbomáx, a management optimization model that simulates forest growth under different forest management regimes (intensity and frequency of thinnings and rotation lengths). A genetic algorithm was used to find the management regime that maximizes the Annual Equivalent Value (AEV) of projects under different market scenarios. We tested our model under a wide variety of possible scenarios for forestry projects. Five tropical plantation species (Alnus jorullensis, Cordia alliodora, Pinus patula, Cupressus lusitanica and Eucalyptus grandis) were evaluated, at discount rates of 4, 7 and 10%, and certified emissions reduction (CER) prices of US$3, 7, 10 and 13. Temporary CERs (tCERs) and long-term CERs (lCERs) prices were considered in the evaluation and were calculated as a variable proportion of CER price. Results showed that optimal forest management is sensible to carbon and timber market conditions. Under each discount rate, as CER price increased, frequency and intensity of thinnings tended to decrease and optimal thinnings and rotation lengths tended to be reached at older ages. The largest AEV were obtained with discount rates of 10%, CER prices of US$13 and rotation lengths of 40 years for all species. For those species with higher timber prices, thinnings tended to be more frequent and at early ages of the plantation. For all species optimal thinnings were found at 35 years of plantation age. tCERs was selected by the model as the best choice to maximize the profitability of the projects. [Copyright &y& Elsevier]

Summary 1 We modelled the growth in estimated biomass of individuals in experimental populations of Chenopodium album grown at two densities and measured sequentially nine times over 128 days. Competition is modelled by coupling individual growth equations and, within the population, the growth rate of a plant at any point in time is a function of its size to the power a , a measure of the degree of size-asymmetry of competition. 2 The growth of individuals in these crowded populations was significantly better fit by a Richards growth model than by models with one fewer parameter (e.g. logistic or Gompertz growth models). The additional parameter determines the location of the inflection point and provides great flexibility in fitting growth curves. Density had a significant effect on this parameter. 3 At the higher density, the maximum size that plants achieved was decreased and the exponential phase of growth was reduced. The estimate of the size-asymmetry parameter a was always greater than 1 and it increased significantly at the higher density. Growth was reduced and the number of very small individuals increased at the higher density, although a few plants still achieved a large size. 4 Our approach combines several recent innovations in the modelling of stand development, including (a) modelling of individual growth with biologically meaningful growth models and (b) modelling the relationship between size and growth of individuals within the population. Sequential, non-destructive data on the growth of individuals over time, in combination with modern statistical computing techniques, can lead to major advances in the modelling of plant population development, providing powerful tools for exploring variation in individual growth and for testing a wide range of hypotheses. [ABSTRACT FROM AUTHOR]

The yielding properties of the cell wall, irreversible wall extensibility (m) and yield threshold (Y), are determined for stage I sporangiophores of Phycomyces blakesleeanus from in-vivo creep experiments, and compared to the values of m and Y previously determined for stage IVb sporangiophores using the same pressureprobe method (Ortega et al., 1989, Biophys. J. 56, 465). In either stage the sporangiophore enlarges (grows) predominately in length, in a specific region termed the 'growing zone', but the growth rates of stage I (5-20 urn · min) are smaller than those of stage IVb (30-70 μm · min). The results demonstrate that this difference in growth rate is the consequence of a smaller magnitude of m for stage I sporangiophores; the obtained values of P (turgor pressure), Y, and P-Y (effective turgor for irreversible wall extension) for stage I sporangiophores are slightly larger than those of stage IVb sporangiophores. Also, it is shown that the magnitude of m for the stage I sporangiophore is regulated by altering the length of the growing zone, L. A relationship between m and L is obtained which can account for the difference between values of m determined for stage I and stage IVb sporangiophores. Finally, it is shown that similar changes in the magnitude of m and ϕ (which have been used interchangeably in the literature as a measure of irreversible wall extensibility) may not always represent the same changes in the cell-wall properties. [ABSTRACT FROM AUTHOR]

Hybrid poplar plantations are becoming increasingly important as a source of income for farmers in northwestern Spain, as rural depopulation and farmers aging prevent landowners from planting other labor-intensive crops. However, plantation owners, usually elderly and without formal forestry background, lack of simple tools to estimate the size and volume of their plantations by themselves. Therefore, farmers are usually forced to rely on the estimates made by the timber companies that are buying their trees. With the objective of providing a simple, but empowering, tool for these forest owners, simple equations based only on diameter were developed to estimate individual tree volume for the Órbigo River basin. To do so, height and diameter growth were measured for 10 years (2009–2019) in 404 trees growing in three poplar plantations in Leon province. An average growth per tree of 1.66 cm year−1 in diameter, 1.52 m year−1 in height, and 0.03 m3 year−1 in volume was estimated, which translated into annual volume increment of 13.02 m3 ha−1 year−1. However, annual volume increment was different among plots due to their fertility, with two plots reaching maximum volume growth around 11 years since planting and another at 13 years, encompassing the typical productivity range in plantations in this region. Such data allowed developing simple but representative linear, polynomial and power equations to estimate volume explaining 93%–98% of the observed variability. Such equations can be easily implemented in any cellphone with a calculator, allowing forest owners to accurately estimate their timber existences by using only a regular measuring tape to measure tree diameter. However, models for height were less successful, explaining only 75%–76% of observed variance. Our approach to generate simplified volume equations has shown to be viable for poplar, but it could be applied to any species for which several volume equations are available. [ABSTRACT FROM AUTHOR]

Leary and Johannsen (2010; Leary and Johannsen. 2010. Using strong inference to falsify differential equation models of sugar maple height growth. MCFNS 2(1):1-11) envision growth modeling as a search for a single precise line like those depicting the laws of physics. However, it is unlikely that such a complex process as tree growth can be captured by our simple, usually empirical models. Instead of carrying out the experiment so as to get a clean result, it may be more realistic to start with enclosing the field of growth trajectories between two boundary lines representing the two opposite explanations of a studied relationship. Understanding complex process is more likely by combining opposites rather than falsifying one of them. Then, the modules delineating the boundaries can be joint in a single model that describes a more complex and fluid central tendency. [ABSTRACT FROM AUTHOR]

• Long-lasting individual tree growth contradicts textbook knowledge. • Mass growth culminates mostly far beyond rotation age. • Spacing, thinning, or fertilization do not cause earlier growth decrease. • Environmental changes may strongly increase level and peristence of growth. The course of tree growth, especially the level and persistence until advanced age, indicates the competitivenes and fitness of trees and determines stand structure and dynamics. The velocity of size growth and aging affects many other plants and animals living at and from trees. Thus forestry and many ecosystem functions and services are depending on the course of tree growth. First, novel empirical findings of particular persisting tree growth in various parts of the world were presented and motivated this review. The revealed increasing, mostly positive, deviations of observed from theoretically expected tree growth directed this review to be based on literature and own long-term experiments, stem analyses, and increment cores from temperate forests. Second, the common growth theory and respective growth equations were revisited; they later were used for analyzing observed courses of dominant trees' mass growth and productivity. Third, tree developments over size and age were analyzed as affected by tree species, site conditions, thinning, and fertilization and enviromental changes. Stem analyses and increment core analyses of Norway spruce (Picea abies (L.) Karst.) representing the growth from 1560 to 1882 indicated a persistence of volume growth beyond age of 300 years even in this historic period of comparatively steady environmental conditions. The mass growth of 735 dominant trees revealed mean culmination ages between 211 and 480 years with the ranking sessile oak (Quercus petraea (Matt.) Liebl.) > European beech (Fagus sylvatica L.) > Norway spruce > Scots pine (Pinus sylvestris L.). Trees on sites with high site index grew quicker, peaked, and decreased earlier in annual growth, whereas trees on poor sites culminated later in terms of age. The courses of annual growth in dependence on tree mass ran more synchronous on different sites. They differed much more in the level than in the rhythm. A total of 910 Scots pines on combined thinned and fertilized compared with control plots revealed for both groups a continous increase of growth until high ages and no preponed size-related growth decrease of the treated trees. For analyzing any modification of the course of growth by environmental changes I used a dataset of 591 cored European beeches and for corroboration 580 permanantly surveyed tree from long-term experiments of the four above mentiond main tree species in Europe. On top of their long-lasting growth all species together showed a strong acceleration of annual growth. Their growth acceleration was obviously caused by environmental changes and the highest in 1850 to 1900. It lessend in the last 50 years, and did not trigger any preponed age- or size related decrease. Finally, I discussed the consequences of the amazingly high and long-lasting tree growth for forest ecology, management and future research. [ABSTRACT FROM AUTHOR]