scholarly journals Impact of Recent Climate Change on Water-Use Efficiency Strategies of Larix sibirica in the Altai-Sayan Mountain Range

Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1103
Author(s):  
Olga V. Churakova (Sidorova) ◽  
Marina V. Fonti ◽  
Rolf T. W. Siegwolf ◽  
Matthias Saurer ◽  
Vladimir S. Myglan

A strong increase in the mean annual air temperature during the past 50 years by up to 0.54 °C was recorded in the Altai region (45°–52° N; 84°–99° E) compared to the global value of 0.07 °C over the period 1901–2008. The impact of the climatic changes on the hydrology are complex in these mountainous forest ecosystems and not fully understood. We aim to reveal differences in the intrinsic water-use efficiencies (iWUE) strategy by larch (Larix sibirica Ledeb.) derived from stable carbon isotopes at contrasting sites, ranging from the steppe (Ersin, Chadan) to high-elevation (Mongun, Koksu) sites of the Altai over the past century. The iWUE trends increased rapidly for all study sites except Chadan, where a decreasing trend after 2010 has been observed. This decline can be related to increased amount of precipitation compared to increased drought at the other sites. In general, the iWUE is increased up to 14% (1985–2019 compared to 1919–1984), which is lower compared to other studies across the globe likely due to harsh climatic conditions. Vapor pressure deficit and maximal air temperature are impacting Siberian larch significantly and affecting their iWUE differently at the high-elevated and steppe sites of the Altai over the past century.

1996 ◽  
Vol 42 (140) ◽  
pp. 136-140 ◽  
Author(s):  
Tsutomu Nakamura ◽  
Masujiro Shimizu

AbstractReduced amounts of snow in the eight winters from 1986-87 to 1993-94 at Nagaoka, Japan, seem to be due to a winter air-temprature rise. The winter air temprature has shown cyclic varition gradual increase in the past 100years. The linear rate of the temperature rise in the past century was calculated as 1.35°C per 100 years. Both the maximum Snow depth and winter precipitation showed an inversely positive correlation with winter mean air temperature, The square of the statistical correlation coefficient r2was calculated as 0.321 and 0.107. respectively. Statistically smoothed curves or the maximum snow depth and winter precipitation showed maximum values in 1940, Fluctuations in deviation of the maximum Snow depth showed smaller values than in precipitation. The minimum winter mean air temperature obtained from a 10 year moving average curve was found in 1942, and the deviation fom the climatic mean changed from negative to positive in 1949. The change in sign or the temperature deviation and the increase of the deviation may be attributable to global warming.


1974 ◽  
Vol 6 (3) ◽  
pp. 218-232 ◽  
Author(s):  
Thomas Callahan

King Stephen's reign has long been recognized as a crucial period for monasticism in England. Many authors have written about alleged anarchical conditions during those nineteen years, and scholars have done a great deal of work on twelfth century English monasticism; nevertheless, comparatively little attention has been paid to the impact of this supposed anarchy on the monastic establishment. This impact is the concern of this essay. Due to the limitation of space, I will confine myself to the material damages suffered by monastic houses during Stephen's reign and will offer an extended summary of my findings.The traditional picture of anarchy in England during Stephen's reign is that the civil wars wreaked havoc with nearly all aspects of life and inflicted massive and long lasting material damages. Medieval writers—most memorably the Peterborough chronicler— emotionally depicted scenes of terror and devastation, and the majority of later scholars—most notably H. W. C. Davis—upheld the basic validity of this picture. During the past century, however, historians have somewhat modified the traditional view. Whereas most medieval writers described an England embroiled in internal warfare for nearly all of Stephen's nineteen year reign, modern scholars have realized that the area of active fighting was more limited and that actual warfare lasted less than half of the reign. Also, modern scholars have shown that many of the occurrences in Stephen's reign were not characterized by aimless chaos and confusion, but rather by purposeful actions directed towards specific ends.


2002 ◽  
Vol 54 (4) ◽  
pp. 315-333 ◽  
Author(s):  
Christina Röcke ◽  
Katie E. Cherry

In this article, we address the topic of death from historic and contemporary perspectives. In the first section, we describe the changes in life expectancy, personal experience, and public awareness of death that have occurred over the past century. In the next section, we examine the impact these changes have had on the mastery of the two developmental tasks in adulthood, acceptance of one's own mortality and coping with the death of a spouse. We describe select findings from the literature on attitudes, fear or acceptance of death, and grief processes. Implications for research, practice, and social change are considered.


1988 ◽  
Vol 15 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Reid A. Bryson

Research over the past century has shown that the rates and magnitudes of climatic change constitute a continuum. Changes have now been identified in the climatic record that range in duration from interannual through decades and centuries to the multi-millennial time-scale. Examples range from the drought years of the 1930 and 1970 decades to the ponderous comings and goings of the ice-ages. More recently it has become clear that some changes can be quite rapid. In recent decades great progress has been made in identifying the causes of climatic variation.The present understanding of the causes of climatic change emphasizes continental drift (or ‘plate tectonics’) at the million-years' scale, with pulses of plate movement producing significant bursts of volcanic activity that may act on the millennial or century scale. At the multi-millennial scale there is growing agreement that the variations in irradiance of the Earth, resulting from slow changes in the Sun-Earth geometry (the so-called Milankovitch variations), exercise the operative control on the timing of ice-ages and interglacials. At the decadal and interannual scales there is less agreement; but there is at least a body of research which suggests that significant volcanic activity is a contributing factor. There is considerable agreement—but little direct evidence—that anthropogenic causes such as increased carbon dioxide and other Man-made or-enhanced trace gases in the atmosphere, will be important in the coming decades.Cultural responses might be expected to differ across this continuum. To assess the expected response to a climatic variation, one must know at least the shape of the response surface.There is probably a critical threshold combination of climatic change magnitude and duration. Human cultures seem to be adapted to frequently-occurring short ‘aberrations’ from the expected climate. Some evidence indicates, on the other hand, that relatively small changes of climates (of the order of a century in duration) have been associated over the past 8,000 years with cultural changes that proved large enough to lead to different names being assigned in perhaps half of the cultural termini identified. A climate model which includes the effect of volcanic aerosols, suggests that most of the climatic changes associated with these globally synchronous cultural termini are related to peaks of volcanic activity. Some apparently catastrophic events have been recognized in this connection.There remains the problem of assessing, in realistic terms, the impact of large-magnitude climatic variations on modern human societies. Of particular concern is the effect of climatic events associated with very large-scale short-term insertions of aerosols into the atmosphere. It is likely that non-equilibrium models of the atmosphere, with specified sea-surface temperatures, would give realistic results if refined to the degree that they could replicate events of lesser magnitude which have occurred in the past century. At present there appear to be no models in which the formulation of the radiative effect of aerosols or gases gives a good match with observed radiative effects. It seems that much more research, including field experiments, will be needed if science is to supply reliable advice to society on the nature of coming climatic changes.


2017 ◽  
Vol 38 (4) ◽  
pp. 1925-1937 ◽  
Author(s):  
Zhiyan Zuo ◽  
Song Yang ◽  
Kang Xu ◽  
Renhe Zhang ◽  
Qiong He ◽  
...  

Author(s):  
A. D. Kitov ◽  

The Munku-Sardyk mountain range (3,491 m) represents the territory of the modern glaciation of The East Sayan. Different forms of transformation of nival-glacial geosystems have been preserved in this range. The processes of transformation and self-organization of geosystems are considered on the example of the Radde glacier and the unique stone glacier. Due to climate change, the glacier has shrunk considerably. Its area has decreased over 100 years from 0.3 to 0.19 km2, and over the last 20 years from 0.19 to 0.09 km2. However, the glacier has processes of self-preservation, slowing down the process of melting the glacier. This transformation of the glacier is manifested as the reservation of surface moraines. The peculiarities of the formation of surface moraines are considered. In the past century, the formation rate of moraines was 0.001 km2/year. Recently, the rate of formation of moraines has increased to 0.02 km2/year. In the second case, the unique stone stream (stone glacier) is an example of the transformation of the classical glacier into a new structure, which at this stage does not depend significantly on the observed warming, and can exist as an independent object for quite some time. The material is supplied by the rock of mountain range, and the transport by the ice bed is formed in winter from groundwater at the level of indigenous rocks, like subsurface ice. The structure of this stone stream is presented as an independent geosystem. It is assumed that the nival-glacial geosystems behave like lag systems. From the analysis of freezing and thawing of soils it follows that the increase and degradation of glaciers should be subject to the law of hystiresis.


Author(s):  
А.N. Odintsov ◽  
L.A. Nichkova ◽  
I.I. Zaruk

This article discusses the impact of anthropogenic pressure on the environment, in particular, the tendency for the average global temperature to change on the earth’s surface. As one of the factors that have a significant effect on the increase in temperature should certainly include an increase in the concentration of carbon dioxide in the atmosphere. Although over the past century of instrumental observations, its concentration has increased from 0.02% to 0.03%, the effect of this change is felt in all corners of the planet. One of the ways to reduce the anthropogenic load is the search for ways to further, more efficiently use the energy of solar radiation to heat various buildings and structures. The article considers the possibility and feasibility of changing the framework of traditional coaxial vacuum tubular solar collectors. The proposed changes in the framework of traditional coaxial vacuum tubular solar collectors will allow the movement of a liquid or gaseous coolant, without changing its phase state, due to the action of gravitational forces. The proposed framework can function completely autonomously and does not require additional energy sources for ability of circulation of the coolant.


2020 ◽  
Vol 12 (11) ◽  
pp. 4717 ◽  
Author(s):  
Kun Huang ◽  
Long Ma ◽  
Jilili Abuduwaili ◽  
Wen Liu ◽  
Gulnura Issanova ◽  
...  

Over the past century, the impacts of human activities on the natural environment have continued to increase. Historic evolution of the environment under anthropogenic influences is an important reference for sustainable social development. Based on the geochemical analyses of a short sediment core of 49 cm from Lake Balkhash, the largest lake in Central Asia, potential factors historically influencing geochemical variation were revealed, and influences of human activity on regional environmental change were reconstructed over the past 150 years. The results showed that the dominant factor inducing changes in potentially toxic elements (V, Cr, Co, Ni, Zn, Cu, Cd, and Pb) is the physical weathering of the terrestrial materials. The variation in Ca content was influenced by the formation of authigenic carbonate. Since 1930, potentially toxic elements (Cr, Co, Ni, Zn, Cu, Cd, and Pb) in the lake sediments have obviously been affected by human activities, but the impact of human activities has not exceeded that of natural terrestrial weathering. In particular, the enrichment factors (EFs) for Cd and Pb reached 1.5. The average ecological risks of Cd were higher than the criterion of 30, suggesting a moderate risk to the local ecosystem in recent years. Total risk indices indicated moderate potential ecological risk for the lake ecology. The results will provide support for the environmental protection and better management practices of the Lake Balkhash watershed.


Author(s):  
V. Naidoo ◽  
K. Wolter ◽  
I. Espie ◽  
A. Kotze

SouthAfrica is home to 9 vulture species, of which 7 are endangered. While the cause of the population declines remains largely speculative, a vast amount of effort has been dedicated towards the protection of populations by ensuring sustainable and safe food sources for the various colonies. Limited focus was placed in the past on efforts related to the rescue and/or rehabilitation (R&R) of injured birds and the release of these birds back into the wild. This paper provides an overview of the causes, the impact and success of 3 organisations involved in R&R efforts of vultures in the Magaliesberg mountain range and surrounding areas over a period of 10 years. Study material included 162 Cape griffon (CGV) and 38 African white-backed (AWBV) vultures. Datasets include the number, sex and age of birds received, the reason the vultures were brought in for R&R, surgical interventions performed and outcomes of rescue efforts. The CGV dominated the rehabilitation attempts. Results further show that a large number of apparently healthy birds were presented for veterinary treatment. The R&R data clearly indicate that the major cause of injuries was birds colliding with overhead pylons, as a high number of soft tissue and skeletal injuries were observed. The study also shows that successful releases of rescued birds are possible. It is concluded that urbanisation has had a major negative impact on vultures around the Magaliesberg mountain range.


Sign in / Sign up

Export Citation Format

Share Document