scholarly journals New and Repeating Tipping Points: The Interplay of Fire, Climate Change, and Deforestation in Neotropical Ecosystems

2020 ◽  
Vol 105 (3) ◽  
pp. 393-404
Author(s):  
Mark B. Bush
Keyword(s):  
Climate Change ◽  
Tree Mortality ◽  
Climatic Conditions ◽  
Tipping Points ◽  
Sensitive Species ◽  
Glacial Cycles ◽  
Plant Migration ◽  
Slowing Down ◽  
The Andes ◽  
History Of

A 370,000-year paleoecological history of fire spanning four glacial cycles provides evidence of plant migration in response to Andean climate change. Charcoal, an indicator of fire, is only occasionally observed in this record, whereas it is ubiquitous in Holocene-aged Andean records. Fire is a transformative agent in Amazonian and Andean vegetation but is shown to be rare in nature. As humans promote fire, fire-free areas become microrefugia for fire-sensitive species. A distinction is drawn between microrefugia resulting from fire-free zones and those caused by unusual climatic conditions. The importance of this distinction lies in the lack of warmer-than-modern microrefugia aiding upslope migration in response to warming, whereas fire-free microrefugia support tree species above modern tree line or in areas of Amazonia least used by humans. The synergy between fire, deforestation, and climate change could promote a state-change in the ecosystem, one where new microrefugia would be needed to maintain biodiversity. Past tipping points are identified to have occurred within ca. 1°C–1.5°C of modern conditions. The recent climatic instability in both Amazonia and the Andes is viewed in the context of ecological flickering, while the drought-induced and fire-induced tree mortality are aspects of critical slowing down; both possibly portending an imminent tipping point.

scholarly journals The future of pastoral farming in a changing climate

2009 ◽  
pp. 69-72 ◽  
Author(s):  
J.A. Palmer
Keyword(s):  
Climate Change ◽  
Public Policy ◽  
New Zealand ◽  
Climatic Conditions ◽  
Anthropogenic Climate Change ◽  
Regulatory Environment ◽  
Market Forces ◽  
Changing Climate ◽  
History Of ◽  
Pastoral Farming

Pastoral farming in New Zealand has always been a dynamic and uncertain business. Climatic conditions, market forces and the regulatory environment confronting pastoral farmers each have a long history of change, often rapidly and markedly. It is not surprising then that pastoral farmers are a resilient bunch. It is also not surprising that in respect of anthropogenic climate change some farmers are sceptical of what they see as another passing fashion in science, public policy and environmentalism - change to be weathered.

scholarly journals Climate variability of the tropical Andes since the late Pleistocene

2009 ◽  
Vol 22 ◽  
pp. 13-25 ◽  
Author(s):  
A. Bräuning
Keyword(s):  
Climate Variability ◽  
Ice Cores ◽  
Climatic Conditions ◽  
Tropical Andes ◽  
Atmospheric Circulation Patterns ◽  
Proxy Records ◽  
The Andes ◽  
Circulation Patterns ◽  
Precipitation Regimes ◽  
History Of

Abstract. Available proxy records witnessing palaeoclimate of the tropical Andes are comparably scarce. Major implications of palaeoclimate development in the humid and arid parts of the Andes are briefly summarized. The long-term behaviour of ENSO has general significance for the climatic history of the Andes due to its impact on regional circulation patterns and precipitation regimes, therefore ENSO history derived from non-Andean palaeo-records is highlighted. Methodological constraints of the chronological precision and the palaeoclimatic interpretation of records derived from different natural archives, such as glacier sediments and ice cores, lake sediments and palaeo-wetlands, pollen profiles and tree rings are addressed and complementary results concerning former climatic conditions are discussed in terms of possible implications of former atmospheric circulation patterns and main climatic forcing factors. During the last years, increasing tree-ring information is getting available from the tropical Andes, providing high-resolution climate-sensitive records covering the past centuries for the study of climate variability.

Origins of Food Production in the High Andes

2021 ◽  
Author(s):  
BrieAnna S. Langlie
Keyword(s):  
Genetic Research ◽  
Climatic Conditions ◽  
Hunter Gatherers ◽  
The Andes ◽  
Ancient People ◽  
History Of ◽  
Andean Highlands ◽  
Village Life ◽  
Infertile Soils

Vertical topography, high altitude, infertile soils, and an arid climate make the Andes of South America a difficult region for agriculture. Nonetheless, archaeologists have found that potatoes, oca, quinoa, and kañawa were first domesticated by ancient famers in and near a region known as the Altiplano. Research indicates that approximately 6,000 years ago hunter-gatherers began to cultivate wild ancestors of these crops. Shortler thereafter, llama and alpaca herders played an important role in developing crop cultivation strategies; potatoes were uniquely adapted to a mobile pastoral lifestyle. By about 1,500 bce there is archaeological evidence that these crops were fully domesticated and supported early village life. Eventually tubers and chenopods were foundational sustenance for civilization and cities across the pre-Hispanic Andean highlands. Breeding over the last four millennia by generations of Indigenous Andean farmers in the diverse environments and climatic conditions of the Andes has resulted in a hugely diverse array of these crops. The outcome of these efforts is that hundreds of varieties of quinoa and over 5,000 varieties of potatoes are grown by Andean farmers in the 21st century. Potatoes in particular are a unique case of domestication for two reasons: (a) ancient farmers figured out how to store them long term through a freeze-drying process; (b) chemicals that are toxic to humans were not bred out of all varieties; rather, ancient people figured out that eating particular clays made the toxic potatoes less bitter and edible. Through paleoethnobotanical and genetic research, archaeologists have begun to shed light on the tangled history of Andean peoples and their crops.

scholarly journals Prolongation of Tick-Borne Encephalitis Cycles in Warmer Climatic Conditions

2019 ◽  
Vol 16 (22) ◽  
pp. 4532 ◽  
Author(s):  
Petr Zeman
Keyword(s):  
Climate Change ◽  
Feedback Loop ◽  
Herd Immunity ◽  
Epidemiological Data ◽  
Climatic Conditions ◽  
Slowing Down ◽  
Tick Borne Encephalitis ◽  
Before And After ◽  
Animal Hosts ◽  
Analysis Of Time Series

Tick-borne encephalitis exhibits profound inter-annual fluctuations in incidence. Previous studies showed that three-fifths of the variation can be explained in terms of four superimposed oscillations: a quasi-biennial, triennial, pentennial, and a decadal cycle. This study was conducted to determine how these cycles could be influenced by climate change. Epidemiological data, spanning from the 1970s to the present, and originating from six regions/countries bridging Scandinavia and the Mediterranean, represented a temporal/latitudinal gradient. Spectral analysis of time series was used to determine variation in the cycles’ length/amplitude with respect to these gradients. The analysis showed that—whereas the lengths of the shorter cycles do not vary substantially—cycles in the decadal band tend to be longer southwards. When comparing the disease’s oscillations before- and after the mid-1990s, a shift towards longer oscillations was detected in the pentennial–decadal band, but not in the biennial– triennial band. Simultaneously, oscillations in the latter band increased in intensity whereas the decadal oscillations weakened. In summary, the rhythm of the cycles has been altered by climate change. Lengthened cycles may be explained by prolonged survival of some animal hosts, and consequently greater inertia in herd immunity changes, slowing down a feedback loop between the herd immunity and amount of virus circulating in nature.

scholarly journals Differences in Quaternary co-divergence reveals community-wide diversification in the mountains of southwest China varied among species

2021 ◽  
Vol 288 (1942) ◽  
pp. 20202567
Author(s):  
Tao Wan ◽  
Jamie R. Oaks ◽  
Xue-Long Jiang ◽  
Huateng Huang ◽  
L. Lacey Knowles
Keyword(s):  
Climate Change ◽  
Genetic Structure ◽  
Southwest China ◽  
Biodiversity Hotspot ◽  
Biological Traits ◽  
Vertebrate Species ◽  
Glacial Cycles ◽  
Relative Independence ◽  
Phylogeographic History ◽  
History Of

The mountains of southwest China (MSWC) is a biodiversity hotspot with highly complex and unusual terrain. However, with the majority of studies focusing on the biogeographic consequences of massive mountain building, the Quaternary legacy of biodiversity for the MSWC has long been overlooked. Here, we took a statistical comparative phylogeography approach to examine factors that shaped community-wide diversification. With data from 30 vertebrate species, the results reveal spatially concordant genetic structure, and temporally clustered co-divergence events associated with river barriers during severe glacial cycles. This indicates the importance of riverine barriers in the phylogeographic history of the MSWC vertebrate community. We conclude that the repeated glacial cycles are associated with co-divergences that are themselves structured by the heterogeneity of the montane landscape of the MSWC. This orderly process of diversification has profound implications for conservation by highlighting the relative independence of different geographical areas in which some, but not all species in communities have responded similarly to climate change and calls for further comparative phylogeographic investigations to reveal the connection between biological traits and divergence pulses in this biodiversity hotspot.

scholarly journals Climate-driven tipping-points could lead to sudden, high-intensity parasite outbreaks

2015 ◽  
Vol 2 (5) ◽  
pp. 140296 ◽  
Author(s):  
Naomi J. Fox ◽  
Glenn Marion ◽  
Ross S. Davidson ◽  
Piran C. L. White ◽  
Michael R. Hutchings
Keyword(s):  
Climate Change ◽  
Large Scale ◽  
Climatic Conditions ◽  
Nematode Parasite ◽  
Parasitic Nematodes ◽  
Temperature Sensitive ◽  
Tipping Points ◽  
Critical Thresholds ◽  
Nonlinear Responses ◽  
Helminth Infections

Parasitic nematodes represent one of the most pervasive and significant challenges to grazing livestock, and their intensity and distribution are strongly influenced by climate. Parasite levels and species composition have already shifted under climate change, with nematode parasite intensity frequently low in newly colonized areas, but sudden large-scale outbreaks are becoming increasingly common. These outbreaks compromise both food security and animal welfare, yet there is a paucity of predictions on how climate change will influence livestock parasites. This study aims to assess how climate change can affect parasite risk. Using a process-based approach, we determine how changes in temperature-sensitive elements of outbreaks influence parasite dynamics, to explore the potential for climate change to influence livestock helminth infections. We show that changes in temperate-sensitive parameters can result in nonlinear responses in outbreak dynamics, leading to distinct ‘tipping-points’ in nematode parasite burdens. Through applying two mechanistic models, of varying complexity, our approach demonstrates that these nonlinear responses are robust to the inclusion of a number of realistic processes that are present in livestock systems. Our study demonstrates that small changes in climatic conditions around critical thresholds may result in dramatic changes in parasite burdens.

Effect of Weather Factors on the Variability of Economic Characteristics in Sunflower Hybrids

2019 ◽  
pp. 70-84
Keyword(s):  
Climate Change ◽  
Climatic Conditions ◽  
Economic Traits ◽  
Weather Factors

This article presents the results of twelve-year trials of the Region and Ryabota simple hybrids and the three-line hybrid Kameniar breeding laboratory of IOC NAANU hybrid labs, and analyzes their adaptation to ongoing climate change. The purpose of our work was to determine the formation of major economic traits in sunflower hybrids, depending on the agro-climatic conditions of the year.

The Historiography of Environmental History

2018 ◽  
Author(s):  
J. R. McNeill
Keyword(s):  
Climate Change ◽  
Environmental History ◽  
Industrial Pollution ◽  
Full Scale ◽  
Environmental Concerns ◽  
The Us ◽  
The World ◽  
History Of ◽  
The 1960S ◽  
The Relationship

This chapter discusses the emergence of environmental history, which developed in the context of the environmental concerns that began in the 1960s with worries about local industrial pollution, but which has since evolved into a full-scale global crisis of climate change. Environmental history is ‘the history of the relationship between human societies and the rest of nature’. It includes three chief areas of inquiry: the study of material environmental history, political and policy-related environmental history, and a form of environmental history which concerns what humans have thought, believed, written, and more rarely, painted, sculpted, sung, or danced that deals with the relationship between society and nature. Since 1980, environmental history has come to flourish in many corners of the world, and scholars everywhere have found models, approaches, and perspectives rather different from those developed for the US context.

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