scholarly journals Human-Induced Enrichment of Potentially Toxic Elements in a Sediment Core of Lake Balkhash, the Largest Lake in Central Asia

2020 ◽  
Vol 12 (11) ◽  
pp. 4717 ◽  
Author(s):  
Kun Huang ◽  
Long Ma ◽  
Jilili Abuduwaili ◽  
Wen Liu ◽  
Gulnura Issanova ◽  
...  
Keyword(s):  
Central Asia ◽  
Sediment Core ◽  
Human Activities ◽  
Toxic Elements ◽  
Potentially Toxic Elements ◽  
Dominant Factor ◽  
Past Century ◽  
The Past ◽  
Lake Balkhash ◽  
The Impact

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.

The impact of climate change and human activities on the Aral Sea Basin over the past 50 years

2020 ◽  
Vol 245 ◽  
pp. 105125 ◽  
Author(s):  
Xuanxuan Wang ◽  
Yaning Chen ◽  
Zhi Li ◽  
Gonghuan Fang ◽  
Fei Wang ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
Aral Sea ◽  
Aral Sea Basin ◽  
Impact Of Climate Change ◽  
The Past ◽  
The Impact

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
Keyword(s):  
Water Use ◽  
Air Temperature ◽  
Siberian Larch ◽  
Larix Sibirica ◽  
Strong Increase ◽  
Past Century ◽  
Mountain Range ◽  
The Past ◽  
Recent Climate ◽  
The Impact

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.

Coastal dune mobility over the past century: A global review

2020 ◽  
Vol 44 (6) ◽  
pp. 814-836 ◽  
Author(s):  
Jinjuan Gao ◽  
David M Kennedy ◽  
Teresa M Konlechner
Keyword(s):  
Human Activities ◽  
Vegetation Cover ◽  
Dominant Role ◽  
Coastal Dunes ◽  
Mediterranean Area ◽  
Global Scale ◽  
Coastal Dune ◽  
Sediment Supply ◽  
Past Century ◽  
The Past

The mobility of coastal dunes is characterised by bio-geomorphological responses related to change in boundary conditions, particularly sediment supply, wind and vegetation cover, as well as human activities. There remains uncertainty regarding the relative importance of these drivers on dune mobility at a global scale. In this study, trends and dominant drivers of coastal dune mobility are synthesised through the literature review focusing on shifts in dune mobility over the last century (1870–2018). In total, 176 individual dunes, with 55 dunes from the Europe-Mediterranean area, 23 from Africa, 30 from North America, 23 from South America, 20 from Oceania and 23 from Asia, are reviewed in this work. The results show that there is a worldwide trend of dune stabilisation, with 93% (164 out of 176) of the reviewed sites showing a loss of bare sand area due to an increase in vegetation cover and urbanisation expansion. Multiple factors have contributed to the stabilisation process, including (a) land-use change such as the change of traditional farming practises, coastal urbanisation and tourism development; (b) dune stabilisation projects; (c) sediment decline caused by the riverine and coastal constructions; and (d) change in climate (i.e. the decrease in windiness, and the increase in temperature and rainfall) and storms. Our results suggest human intervention played a dominant role in altering dune mobility for most dunes during the past century, while climate and storms are also important drivers, especially for dune sites with limited human activities.

The Impact of Anarchy on English Monasticism, 1135-1154

1974 ◽  
Vol 6 (3) ◽  
pp. 218-232 ◽  
Author(s):  
Thomas Callahan
Keyword(s):  
Civil Wars ◽  
Twelfth Century ◽  
Traditional View ◽  
Past Century ◽  
The Past ◽  
The Impact

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.

Death at the End of the 20th Century: Individual Processes and Developmental Tasks in Old Age

2002 ◽  
Vol 54 (4) ◽  
pp. 315-333 ◽  
Author(s):  
Christina Röcke ◽  
Katie E. Cherry
Keyword(s):  
Life Expectancy ◽  
Old Age ◽  
Personal Experience ◽  
Public Awareness ◽  
Developmental Tasks ◽  
Past Century ◽  
Research Practice ◽  
The Past ◽  
And Coping ◽  
The Impact

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.

Civilization and Rapid Climatic Change

1988 ◽  
Vol 15 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Reid A. Bryson
Keyword(s):  
Climatic Change ◽  
Volcanic Activity ◽  
Plate Tectonics ◽  
Field Experiments ◽  
Climatic Changes ◽  
Climatic Variation ◽  
Past Century ◽  
Ice Ages ◽  
The Past ◽  
The Impact

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.

scholarly journals The impact of various grape stock cultivars on the As, Cu, Co and Zn content of the grape berry (must, seed)

2013 ◽  
pp. 39-44
Author(s):  
István Fekete ◽  
Nándor Rakonczás ◽  
Dávid Andrási ◽  
Éva Bódi ◽  
Szilárd Szilágyi ◽  
...  
Keyword(s):  
Toxic Elements ◽  
Grape Berry ◽  
Potentially Toxic Elements ◽  
Grape Berries ◽  
Zn Content ◽  
Abnormal Increase ◽  
Set Up ◽  
Arsenic Copper ◽  
The Impact ◽  
Cu And Zn

Scientific research from the last decades showed that the inappropriate industrial and agricultural production caused an abnormal increase of the potentially toxic elements in the soil. Unfortunately the acidification of the soil is an increasing problem in Hungary. According to Várallyay et al. (2008) 13% of the Hungarian soils are highly acid. Accumulation of toxic elements differs in the genetically diverse plant species. The root of the plant constitutes a filter so that the rootstock is also kind of a filter system, which may prevent that the scion part (such as berry) accumulate high levels of various potentially toxic elements from the soil. The aim of research was to determine how different grape rootstocks influence the As, Co, Cu and Zn content of the musts and seeds. Thus, specifying which of the grape rootstocks takes up the lowest level of these 4 elements (As, Co, Cu and Zn), and accumulates in berries, so could reduce the potentially toxic element load of the grape berries. The grape rootstock collection of the University of Debrecen was set up in 2003 in 3x1 m spacing on immune sandy soil. Grafting of ‘Cserszegi fűszeres’ was started in 2010. We could evaluate yields harvested from 12 rootstock varieties of the experiment in October 2011. We obtained valuable differences in the arsenic, copper, cobalt and zinc concentrations of musts and seeds of ‘Cserszegi fűszeres’ grafted into different rootstocks. The results obtained from the 2011 harvest support the statement that the choice of rootstock might be an important factor to increase food safety. The differences in concentration of the four elements observed in case of the rootstock may have been caused on one hand by the rootstock effect, and on the other hand, the vintage effect has a very significant impact on the vines element uptake. Several years of experimental results will be needed to answer these questions.

scholarly journals ABOUT THE POSSIBILITY OF COOLANT FLOWING THROUGH THE PIPES OF THE SOLAR COLLECTOR SYSTEM FOR HEATING

2020 ◽  
pp. 131-137
Author(s):  
А.N. Odintsov ◽  
L.A. Nichkova ◽  
I.I. Zaruk
Keyword(s):  
Past Century ◽  
Anthropogenic Pressure ◽  
Solar Collectors ◽  
Additional Energy ◽  
The Past ◽  
Collector System ◽  
Average Global Temperature ◽  
Instrumental Observations ◽  
Gaseous Coolant ◽  
The Impact

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.

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