Periodic Increment Research Articles

The productivity of mixed mountain forests comprised of Fagus sylvatica, Picea abies, and Abies alba across Europe

Abstract Mixed mountain forests of European beech (Fagus sylvatica L.), Norway spruce (Picea abies (L.) Karst), and silver fir (Abies alba Mill.) cover a total area of more than 10 million hectares in Europe. Due to altitudinal zoning, these forests are particularly vulnerable to climate change. However, as little is known about the long-term development of the productivity and the adaptation and mitigation potential of these forest systems in Europe, reliable information on productivity is required for sustainable forest management. Using generalized additive mixed models this study investigated 60 long-term experimental plots and provides information about the productivity of mixed mountain forests across a variety of European mountain areas in a standardized way for the first time. The average periodic annual volume increment (PAI) of these forests amounts to 9.3 m3ha−1y−1. Despite a significant increase in annual mean temperature the PAI has not changed significantly over the last 30 years. However, at the species level, we found significant changes in the growth dynamics. While beech had a PAI of 8.2 m3ha−1y−1 over the entire period (1980–2010), the PAI of spruce dropped significantly from 14.2 to 10.8 m3ha−1y−1, and the PAI of fir rose significantly from 7.2 to 11.3 m3ha−1y−1. Consequently, we observed stable stand volume increments in relation to climate change.

Dynamics of a generalized fashion cycle model

We study a four-parameter family of 2D piecewise linear maps with two discontinuity lines. This family is a generalization of the discrete-time version of the fashion cycle model by Matsuyama, which was originally formulated in continuous time. The parameter space of the considered map is characterised by quite a complicated bifurcation structure formed by the periodicity regions of various attracting cycles. Besides the standard period adding and period incrementing structures, there exist incrementing structures with some distinctive properties, as well as novel mixed structures, which we study in detail. The boundaries of many periodicity regions associated with border collision bifurcations of the related cycles are obtained analytically. Several mixed structures are qualitatively described.

Crown Efficiency and Pine Cones Production for Brazilian Pine (Araucaria angustifolia (Bertol.) Kuntze) in South Brazil

Crown efficiency is a relation of growth with the area tree occupies (available area efficiency). Efficiency is associated with the vertical and lateral expansion capacity of the tree and crown, increase, density and light absorption. Thus, our study aimed to evaluate crown efficiency with pine cones∙tree-1 production and dendro/morphometric variables of individual araucaria trees in three forest sites in south Brazil. In each site of each tree, dendrometric and morphometric variables were measured and increment rolls were taken at the breast height diameter level. Together with these data, the morphometric indexes, annual periodic increment in diameter of the last ten years (APId) and efficiency of the crown as a function of APId by the horizontal projection area of the crown (hpac) and number of pine cones∙tree-1 (np) by hpac were calculated. Crown efficiency was modeled as a function of the independent variables hpac, APId, crown length (cl), crown ratio (cr) and np. The accuracy of the adjustment was evaluated by the statistics of the deviance, Akaike’s information criterion and graph of the residuals. The results show that the number of pine cones∙tree-1 increases with annual periodic increment in diameter and diameter. Crown efficiency decreases with increasing hpac, cl and cr, indicating silvicultural treatments should be performed with the removal of trees of larger diameter and crown size. A higher pine cones production and efficiency correlates with forest growth, shape, competition, sociological position (stratum tree occupies) and density.

Measuring energy poverty based on energy embodied in exports of vertical specialisation trade in the construction sector

Energy requirements have expanded significantly in the process of global development while the energy crisis as an issue is becoming a limitation for economic development and environmental sustainability. The construction sector has contributed to the total energy consumption at a national and global level. The quality of human life is still impacted by energy and fuel poverty. This paper aims to examine the effects of energy embodied in intermediate and final goods of the construction sector on energy poverty from a perspective of vertical trade. The modified Energy Development Index (EDI) in the construction sector is applied to measure the extent of energy poverty in a country. Based on the World Input-Output Database (WIOD), the energy embodied in the exports of vertical trade has been measured in the construction sector. The results show that the developing trend in 40 countries increased in different increments in the research period. Comparing the results at the beginning and the end of the research period, the modified EDIs measured by energy embodied in exports of vertical trade increased in 19 countries but decreased in 21 countries. The positive implications for reducing energy/fuel poverty is proposed in policy making and strategic management in foreign trade within the construction sector.

The tortoise and the hare: A race between native tree species and the invasive Chinese tallow

Species-specific growth rate and its response to interspecific competition can determine the winners and losers in forest stand development following disturbance. In the southeastern US, Chinese tallow [Triadica sebifera (L.) Small], a non-native, fast-growing, invasive tree readily displaces native species. However, its rapid early height growth may not compensate for its shorter ultimate stature and earlier senescence when competing with fast growing native tree species of larger stature and longer lifespans. In this study, we compared the growth and competitiveness of Chinese tallow to two native species, slash pine (Pinus elliottii Englem.) and sweetgum (Liquidambar styraciflua L.), using two datasets representing different spatial scales. Plot data from Parris Island, South Carolina obtained by conducting stem analyses, were used to determine height and diameter growth patterns in relation to age and competition. Landscape-scale data from the U.S. Forest Inventory and Analysis (FIA) program were used to determine the relationship of relative importance value (rIV) and periodic annual DBH increment along a competition gradient. We found that Chinese tallow displayed faster diameter and height growth initially, but slowed down considerably after eight years, compared to slash pine. Slash pine was the least tolerant of competition among the three species, and competition had less effect on the growth of Chinese tallow and sweetgum. Our findings suggest that stand-replacing disturbance favors the rapid growth of Chinese tallow for the first decade, even under intense competition. Further, the establishment of native tree species would require effective control of Chinese tallow immediately following disturbance. Efforts to manage Chinese tallow while promoting the growth of native trees may include site preparation to reduce initial abundance of this invasive species, artificial regeneration of native species to provide them ‘head-start’ during the first few years of growth, and release treatments early in stand development to reduce competition for native species.

Growth variability of European beech (Fagus sylvatica L.) natural forests: Dendroclimatic study from Krkonoše National Park

Abstract Long-term temporal development of beech stands in relation to climatic conditions is well documented by dendrochronological analyses. The study aims to identify and describe growth factors affecting natural European beech stands (Fagus sylvatica L.) on permanent research plots in the eastern Krkonoše Mountains, the Czech Republic. The paper focus on radial growth dynamics, frequency and cyclicity, and the effect of climatic factors on diameter increment of beech stands since 1850. The growth development of beech stands was significantly affected by air pollution load in 1977–1989, and increasingly frequent climate extremes in recent years (since 2010). Periodic increment events recurred in approximately 10–18 years’ periods. Stands on research plots responded differently to climatic factors, the main limiting factor being low temperatures during the growing season, frost damages and extreme droughts. The positive influence of temperatures on beech increments was recorded in winter, early spring, and especially in July and August of the current year. Conversely, precipitation in the previous year had higher impact on radial increment, with prevailing negative correlation. The plots were negatively affected by the decrease in sum of precipitation in February and March, but it was the temperature that influenced the beech increment most significantly. Dendrochronological analysis of close-to-nature beech stands provides valuable information on radial forest growth in response to changing climatic conditions.

Assessment of potential trade‐off between maternal colouration and offspring quality in the ornamental “red cherry” shrimpNeocaridina davidi(Bouvier)

Maternal colouration based on carotenoids has been proposed to negatively affect offspring quality in several taxa, since females might trade off their limited carotenoid resources between body colouration and eggs. This study investigated in the ornamental “red cherry” shrimp (Neocaridina davidi) the relationship between maternal colouration and female reproductive performance, as well as offspring quality. Females selected displayed a broad array of body colour, from less coloured to intensely red coloured and were paired with transparent males. The first two spawning events of each female were studied and compared. The number of newly hatched juveniles was associated to maternal weight, but not to maternal colouration. Offspring quality was measured in terms of survival at the end of the 90-day growth period, weight and length increment for 0–30 days and 30–60 days periods, and protein, lipid and glycogen contents in 30-day-old offspring. Yet, neither of these variables was associated to maternal colouration. These results indicate that there is no trade-off between maternal colouration and offspring quality in this species. Furthermore, no association was found between maternal and offspring colouration, evaluated at a similar age. However, body colouration in 180-day old females was significantly higher than in 90-day-old females, indicating that female colouration is strongly influenced by age.

Big Bang Bifurcations in the Tantalus Oscillator Under Biphasic Perturbations

The Tantalus Oscillator is a nonlinear hydrodynamic oscillator with an attractive limit cycle. In this study, we pursue the construction of a biparametric bifurcation diagram for the Tantalus Oscillator under biphasic perturbations. That is the first time that this kind of diagram is built for this kind of oscillator under biphasic perturbations. Results show that biphasic perturbations have no effect when the coupling time is chosen over a wide range of values. This modifies the bifurcation diagram obtained under monophasic perturbations. Now we have the appearance of periodic increment Big Bang Bifurcations. The theoretical results are in excellent agreement with experimental observations.

CARBON STOCK GROWTH IN A SECONDARY ATLANTIC FOREST

ABSTRACT The secondary Atlantic forests play an important role in the context of climate change, acting as a carbon sink for the atmosphere. However, these forests can become a carbon source in case of increased tree mortality. Knowing this change is possible through continuous forest inventories that provide information on the dynamics of tree growth. Thus, the objective of this study was to evaluate the carbon growth dynamics of a Seasonal Semideciduous Forest fragment, with 44.11 ha, located in the Parque Tecnológico de Viçosa - MG. The forest inventories were carried out in twenty plots of 10 m x 50 m, in the years of 2010 and 2015, where all stems with dbh ≥ 5 cm were measured, botanically identified and classified in ecological groups. The stem volume was obtained through volumetric equation. Biomass and carbon stock were quantified for compartments located above the ground (stem, branches and leaves) and below ground (roots). The dynamics of carbon growth were evaluated by Gross Increment (GI) and Periodic Annual Increment in carbon of the species (PAI). The GI was 12.72 MgC ha-1, including the carbon from the stems that were recruited and died during the monitoring period. The carbon stock increased 10.01 MgC ha-1, resulting in an PAI of 2.00 MgC ha-1 year-1. Thus, it is concluded that the forest fragment present positive carbon stock growth due to successional progression, ratifying the importance of secondary forest of the Atlantic forest in the mitigation of greenhouse gases in the atmosphere.

Impact of land use land cover change on ecosystem services: a comparative analysis on observed data and people\u2019s perception in Inle Lake, Myanmar

BackgroundA healthy wetland provides a range of goods and services contributing to human wellbeing. Inle Lake, the first Biosphere Reserve in Myanmar, has been supporting the local inhabitants with ecosystem services (ES) including habitat for a wide range of biodiversity. In the recent years, influenced by land use land cover change (LULCC), the lake has witnessed changes with altered flow of ES, affecting human well-being. Communities’ perceptions are often undermined, when it comes to research LULCC. We analyzed LULCC change data from 1989–2000 to 2000–2014 using Landsat imageries. This was then linked to ES considering dependency through qualitative data collated from participatory rural appraisal tools and structured questionnaires focusing on people’s perception to understand the LULCC dynamics and its implication.ResultsDuring 25 years (1989–2014), there has been a sharp reduction of 164 km2 perennial wetland area in the Inle Lake, which is 4.2-fold higher in 2014 to that of 1989. Similarly, forest area has been declined by 92 km2 (8.56%) in last 25 years. Contrary to this, cropland area showed an increment of 60.67% in 2000 and 64.53% in the year 2014 alone giving a total increase by 268 km2 over the last 25 years and an expansion of 40 km2 seasonal freshwater area were observed showing periodic increment over the time. Communities from the three study areas, namely, Kyaung Taung, Zay Gon and Kyar Taw are found to have high dependence in their surrounding ecosystems. These villages utilizes 17 ES from forest ecosystem, 13 from agro-ecosystem, 10 from seasonal and 4 from perennial water body for their livelihood respectively. Around 93% of the respondents opined that forest ecosystem has decreased over the last 10 years. Around 40% of the respondents reflected an increase in area used for cropland; 43% conversely perceived a declination. About 63% of the respondents perceived such changes have brought huge reduction in availability of freshwater ES. A significant number of respondents (92%) perceived an enormous reduction in seasonal water body during the dry season.ConclusionObserved decreasing trends in forest and perennial wetland areas were consistent with people’s perceived changes. Communities associate loss of forest and wetland area with reduced availability of ES as well as degraded health of the lake.

MODELAGEM DO INCREMENTO DIAMÉTRICO PARA ÁRVORES INDIVIDUAIS DE <i>Araucaria angustifolia </i>(BERTOL.) KUNTZE

Este trabalho teve como objetivo formular modelos de incremento diâmetro para árvores individuais de Araucaria angustifolia. Foram utilizadas medições de 262 indivíduos de araucária amostrados nas parcelas permanentes do Projeto Ecológico de Longa Duração – “Conservação e Manejo Sustentável de Ecossistemas Florestais – Bioma Araucária e suas Transições” (PELD – CNPq). Utilizando análise de correlação, covariância e regressão, foram ajustados modelos de incremento, estratificados em função da classe de diâmetro, variável de maior correlação com o incremento em diâmetro. Foi utilizado o incremento periódico anual, calculado com base no incremento em diâmetro dos indivíduos no período analisado. Os modelos resultaram em boas estimativas do incremento, no entanto, apresentaram resíduos com forte tendência.

Non-homogeneous composite GMR structure to realize increased filtering range.

A non-homogeneous composite guided-mode resonant (GMR) filter structure is proposed that avoids the multi-mode resonance effect and increases resonant wavelength tuning range. The composite filter structure is engineered using a combination of a varied-line-spacing (VLS) grating layer with a wedge-shaped waveguide layer. The grating is fabricated by holographic interference lithography (IL), while the wedge-shaped layer is fabricated using masked ion beam etching (MIBE) technology. The resonant wavelength has been observed to vary as a function of the spatial position on the structure. In the fabricated structure, over a length of 30 mm, the grating period increment is measured to be 149.2 nm, whereas the increment of the waveguide film thickness is approximately 100 nm. Experimental results show that a primary reflectance peak is achieved spanning a wavelength range of 805.8-1119.0 nm. The device is designed using the rigorous coupled-wave analysis (RCWA) method, and the proposed device is toward the practical application of GMR filters.

Radial increment dynamics in Pinus sylvestris stands within the Northern Steppe of Ukraine

The parameters of periodic increment (5-years) and peculiarities of its change depending on age, diameter, height and volume of trunk of Scots pine are determined. The influence of climate conditions (air temperature and precipitation) on the dynamics of radial increment change of Scots pine trees are established. The results of experimental studies, obtained from 20 temporary sample plots of pine stands within the Northern Steppe of Ukraine are presented. We conducted an estimate of radial increment of Scots pine trunks as a basis for development of normative and information support for assessment of biotic productivity of this category of forest. All selected sample trees had different age and biometric parameters. The age of sample trees ranged from 9 to 90 years; diameter at breast height – from 4.0 to 41.7 cm; height – from 4.2 to 30.0 m, trunk volume – from 0.002 to 1.748 m3. It is found that the radial increment of pine stem was significantly dependent on tree age. The highest values of radial increment of Scots pine trees were observed for trees aged up to 20 years. With increasing age, radial increment had a decreasing trend, including 90-year old trees. Regression models of the dependence of radial increment of pine trees on the age and diameter are presented. In the article, the dependence of the values of radial increment of sample trees from types of forest are demonstrated. The highest values of Scots pine radial increment was observed in sugruds and gruds, which were presented in tree samples of 20 years. Comparative analysis of radial increment change in the trees of one age category, which grew in different conditions, was conducted. The older trees had the maximum increment in the conditions of dry sugrud, and the minimum increment in conditions of fresh subor. Also in this article we used generalized chronology of Scots pine radial increment reflecting regional variability of growth in pine trees. The results supplemented the research obtained earlier with new data on the dependence of the pine radial growth rate on forest-biometric parameters. These experimental data, their graph-analytical evaluation yielded an information basis for modeling the radial increment of pine trees, created on the basis of dependence of this parameter on biometric indexes – age and diameter at breast height.

Heterogeneous Society in Binary Choices with Externalities

We study a two-strategy model with negative externalities proposed by Schelling, in a dynamical setting where a society consists of two interacting populations with different behaviors derived from experiments with human participants. The resulting dynamics is a three-dimensional piecewise smooth map with one discontinuity, which inherits some of the characteristics of each homogeneous population dynamics, while others are lost and new ones emerge. We propose a technique to represent the dynamics on a bidimensional space and prove that the heterogeneous society dynamics can be obtained as a linear combination of the dynamics of the two homogeneous populations. As expected, complexity arises with respect to some aspects. Firstly, the number of equilibria expands to infinity and we were able to determine possible focal equilibria in the sense of Schelling. Secondly, when heterogeneity is introduced, the period adding structure of cycles is replaced by a period incrementing structure. Thirdly, the phenomenon of overreaction and cyclic oscillations can be mitigated even if it never completely disappears. We also derive the orbits of cycles of period two and provide numerical evidences of coexistence of cycles with different periods. It is worth noticing that with the heterogeneous society, the dynamics does not depend on the society aggregate choices only, rather on each population choice; neglecting it will make impossible to determine the future evolution of the system. The implications are important as heterogeneity makes the system path-dependent and a policy maker, considering aggregate society choice only, would be unable to make the proper decisions, unless further information is considered.

Seasonal Dynamics of Stem Radial Increment of Pinus taiwanensis Hayata and Its Response to Environmental Factors in the Lushan Mountains, Southeastern China

Seasonal radial-increment records can help to elucidate how tree growth responds to climate seasonality. Such knowledge is critical for understanding the complex growth-climate relationships in subtropical China. We hypothesize that under subtropical monsoon climate characterized by mild winters and hot summers, summer drought constrains stem radial increment, which generally results in growth-limiting factors switching from temperatures in spring and early summer to precipitation in summer and autumn. Here, we monitored intra-annual dynamics of stem radial increment with band dendrometers in a montane stand of Taiwan pine (Pinus taiwanensis Hayata) from Lushan Mountains for two consecutive years (2016–2017). A pronounced bimodal seasonal pattern of stem radial increment was observed in 2016. However, it was less clear in 2017 when late-summer rainfall events occurred in early August. Changing growth-climate relationships were detected throughout the two growing seasons. Stem increments were consistently positively correlated with temperatures before early July, whereas the growth-temperature dependency was gradually weakened and more variable after early July. Conversely, stem increments were significantly correlated with precipitation and soil moisture since early July, indicating that moisture variables were the main factor limiting stem increments in dry period. More precipitation was received in the dry period (July–November) of 2017 as compared with the year 2016, which favoured a wider annual increment in 2017, although growing-season temperature and precipitation was similar between years. Our study suggests a seasonal shift in growth-limiting factors in subtropical forests, which should be explicitly considered in forecasting responses of tree growth to climatic warming.

Análise estrutural e dinâmica de Gymnanthes klotzschiana (Müll. Arg.) em um fragmento de floresta ombrófila mista

A Gymnanthes klotzschiana é uma espécie arbórea pioneira característica das planícies aluviais da Floresta Ombrófila Mista, importante para a conservação das matas ciliares. Portanto este trabalho tem como objetivo analisar a estrutura e a dinâmica de G. klotzschiana em um fragmento de Floresta Ombrófila Mista. Os dados utilizados na pesquisa provêm de um censo (inventário 100%) realizado nos anos de 2007, 2010 e 2013 no Capão da Engenharia Florestal, situado na Universidade Federal do Paraná, Curitiba (PR), com área total de 15,2 ha. As medições foram realizadas em intervalos de 3 anos, sendo mensuradas e identificadas todas ás árvores com circunferência à altura do peito superiores a 30 cm. As análises estruturais foram realizadas com base nos parâmetros populacionais por espécie e a dinâmica foi obtida por meio do acompanhamento do crescimento, ingresso e mortalidade entre os períodos de medição. Os resultados mostram um aumento de indivíduos entre as três medições, passando de 120 para 256 indivíduos, consequentemente, houve um incremento considerável em área basal entre as medições, de 3,26 m² para 6,2 m². A taxa de incremento periódico anual em diâmetro aumentou de 0,31 cm/ano para 0,34 cm/ano, e o incremento periódico anual em área transversal majorou de 0,0280 m² ha-1 para 0,0397 m² ha-1. A taxa de ingresso aumentou gradativamente, enquanto não houve mortalidade no período de medições. A G. klotzschiana possui alto valor de importância para a Floresta Ombrófila Mista, bem como uma dinâmica que favorece o desenvolvimento de outras espécies.

2D discontinuous piecewise linear map: Emergence of fashion cycles.

We consider a discrete-time version of the continuous-time fashion cycle model introduced in Matsuyama, 1992. Its dynamics are defined by a 2D discontinuous piecewise linear map depending on three parameters. In the parameter space of the map periodicity, regions associated with attracting cycles of different periods are organized in the period adding and period incrementing bifurcation structures. The boundaries of all the periodicity regions related to border collision bifurcations are obtained analytically in explicit form. We show the existence of several partially overlapping period incrementing structures, that is, a novelty for the considered class of maps. Moreover, we show that if the time-delay in the discrete time formulation of the model shrinks to zero, the number of period incrementing structures tends to infinity and the dynamics of the discrete time fashion cycle model converges to those of continuous-time fashion cycle model.

Tree leaf trade-offs are stronger for sub-canopy trees: leaf traits reveal little about growth rates in canopy trees.

Can morphological plant functional traits predict demographic rates (e.g., growth) within plant communities as diverse as tropical forests? This is one of the most important next-step questions in trait-based ecology and particularly for global reforestation efforts. Due to the diversity of tropical tree species and their longevity, it is difficult to predict their performance prior to reforestation efforts. In this study, we investigate if simple leaf traits are predictors of the more complex ecological process of plant growth in regenerating selectively logged natural forest within the Wet Tropics (WTs) bioregion of Australia. This study used a rich historical data set to quantify tree growth within plots located at Danbulla National Park and State Forest on the Atherton Tableland. Leaf traits were collected from trees that have exhibited fast or slow growth over the last ~50yr of measurement. Leaf traits were found to be poor predictors of tree growth for trees that have entered the canopy; however, for sub-canopy trees, leaf traits had a stronger association with growth rates. Leaf phosphorus concentrations were the strongest predictor of Periodic Annual Increment (PAI) for trees growing within the sub-canopy, with trees with higher leaf phosphorus levels showing a higher PAI. Sub-canopy tree leaves also exhibited stronger trade-offs between leaf traits and adhere to theoretical predictions more so than for canopy trees. We suggest that, in order for leaf traits to be more applicable to reforestation, size dependence of traits and growth relationships need to be more carefully considered, particularly when reforestation practitioners assign mean trait values to tropical tree species from multiple canopy strata.

Competition Indices and Their Relationship With Basal Area Increment of Araucaria

Models that report the effect of competition are important for forest management since forests with higher levels of competition have lower increment rates, and their use is necessary to plan forest interventions. Thus, this study aimed to assess the effect of competition in the basal area increment of individual trees of Araucaria angustifolia (Bertol.) Kuntze in a natural forest. A total of 397 subject trees were measured, covering the diametric range. The dendrometric and morphometric characteristics of subject trees and their competitors were obtained, and 22 distance-dependent and distance-independent competition indices were calculated, in addition to increment cores extracted radially from the trunk at diameter at breast height. The relationship between models of periodic annual increment in basal area based on competition indices has allowed to obtain R2 values of 0.425 and Syx% ≥ 50.2. The multivariate technique of principal component analysis has shown that three principal components explain 78.43% of total variation. The first component was responsible for explaining 52.95%, with similar eigenvector for 11 competition indices, evidencing that these models can be used to describe especies competition, although they show different variables and mathematical equations in calculations. Results show the importance of competition to predict increment of Araucaria in individual trees.

Biomass and Carbon in a Seasonal Semideciduous Forest in Minas Gerais

ABSTRACT The objective of the present study was to quantify the biomass and carbon stock in a Seasonal Semideciduous Forest remnant in southern Minas Gerais. Forest inventory data taken between 2010 and 2013 in permanent plots, was used to estimate biomass with an allometric equation. Basic wood density (Db) and carbon content were determined in the laboratory and the carbon stock was obtained by multiplying biomass by carbon content. The species with the lowest and highest Db were Nectandra lanceolata (0.38 g cm-3) and Machaerium villosum (0.77 g cm-3). The species that showed the lowest and highest carbon content values were Casearia decandra (41.85%) and Nectandra oppositifolia (46.57%). The biomass stock for the area was 126.92 ± 0.09 t ha-1, which corresponded to 55.91 ± 0.05 t ha -1 of carbon stock and a periodic annual increment of 3.07 t ha-1 year -1.