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2022 ◽  
Vol 4 ◽  
Author(s):  
Joachim Zhu ◽  
Anne Thimonier ◽  
Sophia Etzold ◽  
Katrin Meusburger ◽  
Peter Waldner ◽  
...  

Leaf morphological traits (LMTs) of forest trees have been observed to vary across space and species. However, long-term records of LMTs are scarce, due to a lack of measurements and systematic leaf archives. This leaves a large gap in our understanding of the temporal dynamics and drivers of LMT variations, which may help us understand tree acclimation strategies. In our study, we used long-term LMT measurements from foliar material collections of European beech (Fagus sylvatica) and Norway spruce (Picea abies), performed every second year from 1995 to 2019 on the same trees within the Swiss Long-term Forest Ecosystem Research Program LWF. The 11 study plots (6 beech, 4 spruce, and 1 mixed) are distributed along gradients of elevation (485–1,650 m a.s.l.), mean annual precipitation (935–2142 mm), and mean annual temperature (3.2–9.8°C). The investigated LMTs were (i) leaf or needle mass, (ii) leaf area or needle length, and (iii) leaf mass per area or needle mass per length. We combined this unique data set with plot variables and long-term data on potential temporal drivers of LMT variations, including meteorological and tree trait data. We used univariate linear regressions and linear mixed-effects models to identify the main spatial and temporal drivers of LMT variations, respectively. For beech LMTs, our temporal analysis revealed effects of mast year and crown defoliation, and legacy effects of vapor pressure deficit and temperature in summer and autumn of the preceding year, but no clear long-term trend was observed. In contrast, spruce LMTs were mainly driven by current-year spring conditions, and only needle mass per length showed a decreasing long-term trend over the study period. In temporal models, we observed that LMTs of both species were influenced by elevation and foliar nutrient concentrations, and this finding was partly confirmed by our spatial analyses. Our results demonstrate the importance of temporal analysis for determining less recognized drivers and legacy effects that influence LMTs, which are difficult to determine across space and species. The observed differences in the temporal drivers of beech and spruce LMTs suggest differences in the adaptation and acclimation potential of the two species.


2021 ◽  
pp. 62-66
Author(s):  
А.A. Vasiliev ◽  
Д. Шпопер ◽  
Yu.V. Pechatnova

The research is aimed at finding ways to fill the regulatory vacuum in which digital technologies develop.The article provides an assessment of the positive and negative impact of digitalization on public relations,highlights the problems associated with the legal regulation of public relations complicated by the use ofdigital technologies or the participation of artificial intelligence, analyzes the degree of knowledge of theproblem in legal science and the proposed models of legal regulation of digitalization. The authors haveconcluded that the development of digital technologies demonstrates a long-term trend towards a decreasein the protective abilities of existing legal institutions, and therefore, a public request is formed for theisolation in the system of international scientific law of a set of legal norms regulating scientific and technicalcooperation in the digitalization of science and study of informatization processes.


2021 ◽  
pp. 25-57
Author(s):  
Georg Koopmann ◽  
Klaus Matthies ◽  
Beate Reszat
Keyword(s):  

2021 ◽  
Author(s):  
THEODORE MODIS

A correlation has been observed between the US GDP and the number of sunspots as well as between the Dow Jones Industrial Average and the number of sunspots. The data cover 80 years of history. The observed correlations permit forecasts for the GDP and for the stock market in America with a future horizon of 10 years. Both being above their long-term trend they are forecasted to go over a peak around Jun-2008.


2021 ◽  
Author(s):  
François Ritter

Abstract. Errors, gaps and outliers complicate and sometimes invalidate the analysis of time series. While most fields have developed their own strategy to clean the raw data, no generic procedure has been promoted to standardize the pre-processing. This lack of harmonization makes the inter-comparison of studies difficult, and leads to screening methods that are usually ambiguous or case-specific. This study provides a generic pre-processing procedure (called past, implemented in R) dedicated to any univariate time series. Past is based on data binning and decomposes the time series into a long-term trend and a cyclic component (quantified by a new metric, the Stacked Cycles Index) to finally aggregate the data. Outliers are flagged with an enhanced Boxplot rule called Logbox. Three different Earth Science datasets (contaminated with gaps and outliers) are successfully cleaned and aggregated with past. This illustrates the robustness of this procedure that can be valuable to any discipline.


MAUSAM ◽  
2021 ◽  
Vol 51 (1) ◽  
pp. 69-74
Author(s):  
S. K. PESHIN ◽  
J. N. DEWHARE ◽  
R. C. BHATIA ◽  
S. K. SRIVASTAV

Ozone observations taken during the past 23-39 years by Dobson Spectrophotometers at Delhi, Varanasi, Pune and Kodikanal have been analysed to examine its long-term trend over Indian stations. An increasing trend of this species over the years has been noticed at all the places, except at Varanasi, where a decreasing trend has been found. The cause of these trends could be attributed, partly, to the trends of ozone in the troposphere. The results also indicate that there are certain recent changes in ozone levels at the Indian stations. These changes are less apparent in long-term trend analysis of total ozone data as the increase in tropospheric ozone has a compensating effect to the decrease in ozone at stratospheric levels.


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