scholarly journals The social drift of trees. Consequence for growth trend detection, stand dynamics, and silviculture

Author(s):  
Hans Pretzsch

AbstractRecently, many studies worldwide tapped tree ring pattern for detection of growth events and trends caused by weather extremes and climate change. As long-term experiments with permanent survey of all trees are rare, growth trend analyses are mostly based on retrospective measurements of growth via increment coring or stem analyses of the remaining individual trees in older forest stands. However, the growth of the survivor trees in older stands may only unsufficiently represent the course of growth of the dominant trees throughout the stand development. Here, the more than 100 years survey data of the European beech (Fagus sylvatica L.) thinning experiment Fabrikschleichach in South Germany are used to show the long-term changes in social ranking of trees and their consequences for growth trend detection by retrospective tree ring analyses, for stand dynamics and silvicultural management. Firstly, a significant social upwards drift of initially medium-sized trees till 2010 is shown based on the trees' percentiles in the stem diameter distribution in 1904 versus 2010. The social climbing is stronger on the thinned compared to the unthinned plots. Secondly, we show that 40–60% of the 100 tallest trees in 1904 were replaced by social climbers and down-ranked below the 100 tallest trees till 2010. Linear mixed model analyses reveal that the long-term trend of the diameter growth of the 100 dominant survivors in 2010 was on average by 23% steeper than the trend of the 100 tallest starters in 1904. This indicates that the survivors had a steeper and longer lasting growth than the originally dominant trees. Thirdly, the diameter growth trend in the last 20 years, from 1990 to 2010, is analyzed in dependency on the current and past social position. A linear model shows that early subdominance or suppression can significantly steepen the growth trend a century later and vice versa.Finally, we discuss the implications of the social drift for the survivor-based growth trend analyses, for the stand dynamics, and silvicultural management.

2019 ◽  
Vol 16 (24) ◽  
pp. 4815-4827
Author(s):  
Rachel Dietrich ◽  
Madhur Anand

Abstract. With increasing awareness of the consequences of climate change for global ecosystems, the focus and application of tree ring research have shifted to reconstruction of long-term climate-related trends in tree growth. Contemporary methods for estimating and removing biological growth trends from tree ring series (standardization) are ill-adapted to shade-tolerant species, leading to biases in the resultant chronologies. Further, many methods, including regional curve standardization (RCS), encounter significant limitations for species in which accurate age estimation is difficult. In this study we present and test two tree ring standardization models that integrate tree size in the year of ring formation into the estimation of the biological growth trend. The first method, dubbed size-deterministic standardization (SDS), uses tree diameter as the sole predictor of the growth trend. The second method includes the combined (COMB) effects of age and diameter. We show that both the SDS and COMB methods reproduce long-term trends in simulated tree ring data better than conventional methods; this result is consistent across multiple species. Further, when applied to real tree ring data, the SDS and COMB models reproduce long-term, time-related trends as reliably as traditional RCS and more reliably than other common standardization methods (i.e. C-method, basal area increments, conservative detrending). We recommend the inclusion of tree size in the year of ring formation in future tree ring standardization models, particularly when dealing with shade-tolerant species, as it does not compromise model accuracy and allows for the inclusion of unaged trees.


2019 ◽  
Author(s):  
Rachel Dietrich ◽  
Madhur Anand

Abstract. With increasing awareness of the consequences of climate change for global ecosystems, the focus and application of tree-ring research has shifted to reconstruction of long-term climate-related trends in tree growth. Contemporary methods for removing the biological growth-trend from tree-ring series (standardization) are ill-adapted to shade-tolerant species, leading to biases in the resultant chronology. Further, many methods, including regional curve standardization (RCS), encounter significant limitations for species in which accurate age estimation is difficult. In this study we present and test two tree-ring standardization models that integrate tree size in the year of ring formation into the estimation of the biological growth-trend. The first method, dubbed size deterministic standardization (SDS), uses tree diameter as the sole predictor of the growth-trend. The second method includes the combined (COMB) effects of age and diameter. We show that both the SDS and COMB methods reproduce long-term trends in simulated tree-ring data better than conventional methods – this result is consistent across multiple species. Further, when applied to real tree-ring data, the COMB method is more parsimonious than its than RCS. We recommend the inclusion of tree size in the year of ring formation in future tree-ring standardization models, particularly when dealing with shade-tolerant species, as it does not compromise model parsimony and allows for the inclusion of unaged trees.


2007 ◽  
pp. 27-45
Author(s):  
B. Titov ◽  
I. Pilipenko ◽  
A. Danilov-Danilyan

The report considers how the state economic policy contributes to the national economic development in the midterm perspective. It analyzes main current economic problems of the Russian economy, i.e. low effectiveness of the social system, high dependence on export industries and natural resources, high monopolization and underdeveloped free market, as well as barriers that hinder non-recourse-based business development including high tax burden, skilled labor deficit and lack of investment capital. We propose a social-oriented market economy as the Russian economic model to achieve a sustainable economic growth in the long-term perspective. This model is based on people’s prosperity and therefore expanding domestic demand that stimulates the growth of domestic non-resource-based sector which in turn can accelerate annual GDP growth rates to 10-12%. To realize this model "Delovaya Rossiya" proposes a program that consists of a number of directions and key groups of measures covering priority national projects, tax, fiscal, monetary, innovative-industrial, trade and social policies.


2016 ◽  
Vol 2 (2) ◽  
pp. 110
Author(s):  
Hava Rexhep

The aging is not only a personal but also a social challenge from several aspects, several dimensions; a challenge aiming to build system approaches and solutions with a long term importance. Aims: the main aim of this research is to investigate the conditions and challenges in the modern living of the old people, primarily in terms of the social care. However, this research is concentrated on a big group of the population and their challenges are the most intensive in the modern living. The investigation of the conditions and challenges in the aging are basis and encouragement in realizing the progressive approaches in order to improve the modern living of the old people. The practical aim of the research is a deep investigation and finding important data, analyzing the basic indicators of the conditions, needs and challenges in order to facilitate the old population to get ready for the new life. Methods and techniques: Taking into consideration the complexity of the research problem, the basic methodological approach is performed dominantly by descriptive-analytical method. The basic instrument for getting data in the research is the questionnaire with leading interview for the old people. Results: The research showed that the old people over 70-79 years old in a bigger percentage manifested difficulties primarily related to the functional dependency, respectively 39,33 % of the participants in this category showed concern about some specific functional dependency from the offered categories. The percentage of the stomach diseases with 38,33 % is important, as well as the kidney diseases with 32,83% related to the total population and the category of the old people over 80. Conclusion: The old people very often accept the life as it is, often finding things fulfilled with tolerance and satisfaction. However the health problems of the old people are characterized with a dominant representation. The chronic diseases and the diseases characteristic for the aging are challenge in organizing adequate protection which addresses to taking appropriate regulations, programs and activities.


2020 ◽  
Author(s):  
Anthony D Mancini

In this commentary, I argue that the mental health impact of COVID-19 will show substantial variation across individuals, contexts, and time. Further, one key contributor to this variation will be the proximal and long-term impact of COVID-19 on the social environment. In addition to the mental health costs of the pandemic, it is likely that a subset of people will experience improved social and mental health functioning.


2018 ◽  
Vol 1 (1) ◽  
pp. 16
Author(s):  
Lisa Guenther

In The Body in Pain, Elaine Scarry analyzes the structure of torture as an unmaking of the world in which the tools that ought to support a person’s embodied capacities are used as weapons to break them down. The Security Housing Unit (SHU) of California’s Pelican Bay State Prison functions as a weaponized architecture of torture in precisely this sense; but in recent years, prisoners in the Pelican Bay Short Corridor have re-purposed this weaponized architecture as a tool for remaking the world through collective resistance. This resistance took the form of a hunger strike in which prisoners exposed themselves to the possibility of biological death in order to contest the social and civil death of solitary confinement. By collectively refusing food, and by articulating the meaning and motivation of this refusal in articles, interviews, artwork, and legal documents, prisoners reclaimed and expanded their perceptual, cognitive, and expressive capacities for world-making, even in a space of systematic torture.


Author(s):  
Michael Moehler

This book develops a novel multilevel social contract theory that, in contrast to existing theories in the liberal tradition, does not merely assume a restricted form of reasonable moral pluralism, but is tailored to the conditions of deeply morally pluralistic societies that may be populated by liberal moral agents, nonliberal moral agents, and, according to the traditional understanding of morality, nonmoral agents alike. To develop this theory, the book draws on the history of the social contract tradition, especially the work of Hobbes, Hume, Kant, Rawls, and Gauthier, as well as on the work of some of the critics of this tradition, such as Sen and Gaus. The two-level contractarian theory holds that morality in its best contractarian version for the conditions of deeply morally pluralistic societies entails Humean, Hobbesian, and Kantian moral features. The theory defines the minimal behavioral restrictions that are necessary to ensure, compared to violent conflict resolution, mutually beneficial peaceful long-term cooperation in deeply morally pluralistic societies. The theory minimizes the problem of compliance by maximally respecting the interests of all members of society. Despite its ideal nature, the theory is, in principle, applicable to the real world and, for the conditions described, most promising for securing mutually beneficial peaceful long-term cooperation in a world in which a fully just society, due to moral diversity, is unattainable. If Rawls’ intention was to carry the traditional social contract argument to a higher level of abstraction, then the two-level contractarian theory brings it back down to earth.


Author(s):  
Detlef Pollack ◽  
Gergely Rosta

The case of East Germany raises the question of why religion and church, which had fallen to an unprecedentedly low level after four decades of suppression, have not recovered since 1989. The repressive church politics of the SED were undoubtedly the decisive factor in the unique process of minoritizing churches in the GDR. However, other external factors such as increasing prosperity, socio-structural transformation, and the expansion of the leisure and entertainment sector played an important role, too. In addition, church activity itself probably also helped to weaken the social position of churches. The absence of a church renaissance after 1990 can be explained by several factors, such as the long-term effects of the break with tradition caused by the GDR system, the political and moral discrediting of the church by the state security service, and people’s dwindling confidence in the church, which was suddenly seen as a non-representative Western institution.


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