scholarly journals Humboldt’sTableau Physiquerevisited

2019 ◽  
Vol 116 (26) ◽  
pp. 12889-12894 ◽  
Author(s):  
Pierre Moret ◽  
Priscilla Muriel ◽  
Ricardo Jaramillo ◽  
Olivier Dangles
Keyword(s):  
Environmental Changes ◽  
Original Data ◽  
Range Shift ◽  
Tree Line ◽  
Tropical Andes ◽  
Altitudinal Distribution ◽  
Climate Change Effects ◽  
Altitudinal Shift ◽  
History Of ◽  
Vegetation Belt

Alexander von Humboldt’sTableau Physique(1807) has been one of the most influential diagrams in the history of environmental sciences. In particular, detailed observations of the altitudinal distribution of plant species in the equatorial Andes, depicted on a cross-section of Mt. Chimborazo, allowed Humboldt to establish the concept of vegetation belt, thereby laying the foundations of biogeography. Surprisingly, Humboldt’s original data have never been critically revisited, probably due to the difficulty of gathering and interpreting dispersed archives. By unearthing and analyzing overlooked historical documents, we show that the top section of theTableau Physique, above the tree line, is an intuitive construct based on unverified and therefore partly false field data that Humboldt constantly tried to revise in subsequent publications. This finding has implications for the documentation of climate change effects in the tropical Andes. We found that Humboldt’s primary plant data above tree line were mostly collected on Mt. Antisana, not Chimborazo, which allows a comparison with current records. Our resurvey at Mt. Antisana revealed a 215- to 266-m altitudinal shift over 215 y. This estimate is about twice lower than previous estimates for the region but is consistent with the 10- to 12-m/decade upslope range shift observed worldwide. Our results show the cautious approach needed to interpret historical data and to use them as a resource for documenting environmental changes. They also profoundly renew our understanding of Humboldt’s scientific thinking, methods, and modern relevance.

scholarly journals Lean Pattern in an Altitude Range Shift of a Tree Species: Abies pinsapo Boiss.

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1451
Author(s):  
Antonio González-Hernández ◽  
Diego Nieto-Lugilde ◽  
Julio Peñas ◽  
Francisca Alba-Sánchez
Keyword(s):  
Lower Limit ◽  
Leading Edge ◽  
Climatic Conditions ◽  
Range Shift ◽  
Distribution Models ◽  
Altitudinal Distribution ◽  
Altitudinal Shift ◽  
Abies Pinsapo ◽  
And Migration

Organisms modify their geographical distributions in response to changes in environmental conditions, or modify their affinity to such conditions, to avoid extinction. This study explored the altitudinal shift of Abies pinsapo Boiss. in the Baetic System. We analysed the potential distribution of the realised and reproductive niches of A. pinsapo populations in the Ronda Mountains (Southern Spain) by using species distribution models (SDMs) for two life stages within the current populations. Then, we calculated the species’ potential altitudinal shifts and identified the areas in which the processes of persistence and migration predominated. The realised and reproductive niches of A. pinsapo are different to one another, which may indicate a displacement in its altitudinal distribution owing to changes in the climatic conditions of the Ronda Mountains. The most unfavourable conditions for the species indicate a trailing edge (~110 m) at the lower limit of its distribution and a leading edge (~55 m) at the upper limit. Even though the differences in the altitudinal shifts between the trailing and leading edges will not cause the populations to become extinct in the short term, they may threaten their viability if the conditions that are producing the contraction at the lower limit persist in the long term.

Sustainability Failure in the Antimicrobial Stewardship Program in a Secondary Care Hospital from Cuba: A Historical Review of 30 Years and 3 Shots

2020 ◽  
Vol 18 ◽  
Author(s):  
Humberto Guanche Garcell ◽  
Juan José Pisonero Socias ◽  
Gilberto Pardo Gómez
Keyword(s):  
Antimicrobial Stewardship ◽  
Historical Review ◽  
Original Data ◽  
Care Hospital ◽  
Antimicrobial Stewardship Program ◽  
Continuous Quality ◽  
Stewardship Program ◽  
History Of ◽  
Health Organization

Background: During the last 30 years an antimicrobial stewardship program (ASP) was implemented in a facility with periods of weakness. We aim to describe the history of the sustainability failure in the local ASP. Methods: A historical review was conducted using original data from the facility library and papers published. An analysis of factors related to the failure was conducted based on the Doyle approach. Results: The first ASP was implemented from 1989 to 1996 based on the international experiences and contributes to the improvement in the quality of prescription, reduction of 52% in cost and in the incidence of nosocomial infection. The second program restarts in 2008 and decline in 2015, while the third program was guided by the Pan-American Health Organization from 2019. This program, in progress, is more comprehensive than previous ones and introduced as a novel measure the monitoring of antibiotic prophylaxis in surgery. The factors related to the sustainability were considered including the availability of antimicrobials, the leader´s support, safety culture, and infrastructure. Conclusions: The history behind thirty years of experiences in antimicrobial stewardship programs has allowed us to identify the gaps that require proactive strategies and actions to achieve sustainability and continuous quality improvement.

scholarly journals Current understanding on the Cambrian Explosion: questions and answers

PalZ ◽  
2021 ◽  
Author(s):  
Xingliang Zhang ◽  
Degan Shu
Keyword(s):  
Environmental Changes ◽  
Size Variation ◽  
Progressive Increase ◽  
Cambrian Explosion ◽  
Time Interval ◽  
Early Cambrian ◽  
Ecological Processes ◽  
Questions And Answers ◽  
Evolutionary Event ◽  
History Of

AbstractThe Cambrian Explosion by nature is a three-phased explosion of animal body plans alongside episodic biomineralization, pulsed change of generic diversity, body size variation, and progressive increase of ecosystem complexity. The Cambrian was a time of crown groups nested by numbers of stem groups with a high-rank taxonomy of Linnaean system (classes and above). Some stem groups temporarily succeeded while others were ephemeral and underrepresented by few taxa. The high number of stem groups in the early history of animals is a major reason for morphological gaps across phyla that we see today. Most phylum-level clades achieved their maximal disparity (or morphological breadth) during the time interval close to their first appearance in the fossil record during the early Cambrian, whereas others, principally arthropods and chordates, exhibit a progressive exploration of morphospace in subsequent Phanerozoic. The overall envelope of metazoan morphospace occupation was already broad in the early Cambrian though it did not reach maximal disparity nor has diminished significantly as a consequence of extinction since the Cambrian. Intrinsic and extrinsic causes were extensively discussed but they are merely prerequisites for the Cambrian Explosion. Without the molecular evolution, there could be no Cambrian Explosion. However, the developmental system is alone insufficient to explain Cambrian Explosion. Time-equivalent environmental changes were often considered as extrinsic causes, but the time coincidence is also insufficient to establish causality. Like any other evolutionary event, it is the ecology that make the Cambrian Explosion possible though ecological processes failed to cause a burst of new body plans in the subsequent evolutionary radiations. The Cambrian Explosion is a polythetic event in natural history and manifested in many aspects. No simple, single cause can explain the entire phenomenon.

Environmental evolution and anthropogenic forcing in the Garigliano coastal plain (Italy) during the Holocene

The Holocene ◽  
2021 ◽  
pp. 095968362110032
Author(s):  
Halinka Di Lorenzo ◽  
Pietro Aucelli ◽  
Giuseppe Corrado ◽  
Mario De Iorio ◽  
Marcello Schiattarella ◽  
...  
Keyword(s):  
Human Activity ◽  
Coastal Plain ◽  
Forest Cover ◽  
Environmental Changes ◽  
Pollen Data ◽  
Human Environment ◽  
The Holocene ◽  
Natural Processes ◽  
History Of ◽  
The Rich

The Garigliano alluvial-coastal plain, at the Latium-Campania border (Italy), witnessed a long-lasting history of human-environment interactions, as demonstrated by the rich archaeological knowledge. With the aim of reconstructing the evolution of the landscape and its interaction with human activity during the last millennia, new pollen results from the coastal sector of the Garigliano Plain were compared with the available pollen data from other nearby sites. The use of pollen data from both the coastal and marine environment allowed integrating the local vegetation dynamics within a wider regional context spanning the last 8000 years. The new pollen data presented in this study derive from the analysis of a core, drilled in the coastal sector, which intercepted the lagoon-marshy environments that occurred in the plain as a response to the Holocene transgression and subsequent coastal progradation. Three radiocarbon ages indicate that the chronology of the analyzed core interval ranges from c. 7200 to c. 2000 cal yr BP. The whole data indicate that a dense forest cover characterized the landscape all along the Prehistoric period, when a few signs of human activity are recorded in the spectra, such as cereal crops, pasture activity and fires. The main environmental changes, forced by natural processes (coastal progradation) but probably enhanced by reclamation works, started from the Graeco-Roman period and led to the reduction of swampy areas that favoured the colonisation of the outer plain.

scholarly journals Neoglacial history of Robson Glacier, British Columbia

2017 ◽  
Vol 54 (11) ◽  
pp. 1153-1164 ◽  
Author(s):  
B.H. Luckman ◽  
M.H. Masiokas ◽  
K. Nicolussi
Keyword(s):  
British Columbia ◽  
Little Ice Age ◽  
Ice Age ◽  
Tree Line ◽  
Canadian Rockies ◽  
The Holocene ◽  
Forest Sites ◽  
History Of ◽  
Subfossil Wood ◽  
Glacier Advance

As glaciers in the Canadian Rockies recede, glacier forefields continue to yield subfossil wood from sites overridden by these glaciers during the Holocene. Robson Glacier in British Columbia formerly extended below tree line, and recession over the last century has progressively revealed a number of buried forest sites that are providing one of the more complete records of glacier history in the Canadian Rockies during the latter half of the Holocene. The glacier was advancing ca. 5.5 km upvalley of the Little Ice Age terminus ca. 5.26 cal ka BP, at sites ca. 2 km upvalley ca. 4.02 cal ka BP and ca. 3.55 cal ka BP, and 0.5–1 km upvalley between 1140 and 1350 A.D. There is also limited evidence based on detrital wood of an additional period of glacier advance ca. 3.24 cal ka BP. This record is more similar to glacier histories further west in British Columbia than elsewhere in the Rockies and provides the first evidence for a post-Hypsithermal glacier advance at ca. 5.26 cal ka BP in the Rockies. The utilization of the wiggle-matching approach using multiple 14C dates from sample locations determined by dendrochronological analyses enabled the recognition of 14C outliers and an increase in the precision and accuracy of the dating of glacier advances.

scholarly journals Gold, timber, war and parks : A history of the Rushworth Forest in central Victoria

2010 ◽  
Vol 122 (2) ◽  
pp. 130 ◽  
Author(s):  
Ruth E. Lawrence ◽  
Marc P. Bellette
Keyword(s):  
World War Ii ◽  
Gold Mining ◽  
Forest Cover ◽  
Environmental Changes ◽  
Resource Utilisation ◽  
World War ◽  
Mining Operations ◽  
Prisoner Of War ◽  
Central Victoria ◽  
History Of

The Rushworth Forest is a Box and Ironbark open sclerophyll forest in central Victoria that has been subject to a long history of gold mining activity and forest utilisation. This paper documents the major periods of land use history in the Rushworth Forest and comments on the environmental changes that have occurred as a result. During the 1850s to 1890s, the Forest was subject to extensive gold mining operations, timber resource use, and other forest product utilisation, which generated major changes to the forest soils, vegetation structure and species cover. From the 1890s to 1930s, concern for diminishing forest cover across central Victoria led to the creation of timber reserves, including the Rushworth State Forest. After the formation of a government forestry department in 1919, silvicultural practices were introduced which aimed at maximising the output of tall timber production above all else. During World War II, the management of the Forest was taken over by the Australian Army as Prisoner of War camps were established to harvest timber from the Forest for firewood production. Following the War, the focus of forestry in Victoria moved away from the Box and Ironbark forests, but low value resource utilisation continued in the Rushworth Forest from the 1940s to 1990s. In 2002, about one-third of the Forest was declared a National Park and the other two-thirds continued as a State Forest. Today, the characteristics of the biophysical environment reflect the multiple layers of past land uses that have occurred in the Rushworth Forest.

scholarly journals The Corporate War Dead: New Perspectives on the Demographics of American and British Contractors

2018 ◽  
Vol 46 (1) ◽  
pp. 3-24 ◽  
Author(s):  
Ori Swed ◽  
Jae Kwon ◽  
Bryan Feldscher ◽  
Thomas Crosbie
Keyword(s):  
Lived Experience ◽  
Original Data ◽  
Military Operations ◽  
Data Set ◽  
Military Organizations ◽  
Security Industry ◽  
Legal Implications ◽  
History Of ◽  
War Dead ◽  
Military Activity

From an obscure sector synonymous with mercenaryism, the private military and security industry has grown to become a significant complementing instrument in military operations. This rise has brought with it a considerable attention. Researchers have examined the role of private military and security companies in international relations as well as the history of these companies, and, above all, the legal implications of their use in the place of military organizations. As research progresses, a significant gap has become clear. Only a handful of studies have addressed the complex of issues associated with contractors’ demographics and lived experience. This article sheds some light over this lacuna, examining contractors’ demographics using descriptive statistics from an original data set of American and British contractors who died in Iraq between the years 2003 and 2016. The article augments our understanding of an important population of post-Fordist-contracted workforce, those peripheral workers supplementing military activity in high-risk occupations with uncertain long-term outcomes.

scholarly journals Climate-mediated changes to mixed-layer properties in the Southern Ocean: assessing the phytoplankton response

2008 ◽  
Vol 5 (3) ◽  
pp. 847-864 ◽  
Author(s):  
P. W. Boyd ◽  
S. C. Doney ◽  
R. Strzepek ◽  
J. Dusenberry ◽  
K. Lindsay ◽  
...  
Keyword(s):  
Climate Change ◽  
Southern Ocean ◽  
Climate Model ◽  
Environmental Changes ◽  
Environmental Control ◽  
Climate System Model ◽  
Climate Change Effects ◽  
Detection And Attribution ◽  
Key Species ◽  
Phytoplankton Functional Groups

Abstract. Concurrent changes in ocean chemical and physical properties influence phytoplankton dynamics via alterations in carbonate chemistry, nutrient and trace metal inventories and upper ocean light environment. Using a fully coupled, global carbon-climate model (Climate System Model 1.4-carbon), we quantify anthropogenic climate change relative to the background natural interannual variability for the Southern Ocean over the period 2000 and 2100. Model results are interpreted using our understanding of the environmental control of phytoplankton growth rates – leading to two major findings. Firstly, comparison with results from phytoplankton perturbation experiments, in which environmental properties have been altered for key species (e.g., bloom formers), indicates that the predicted rates of change in oceanic properties over the next few decades are too subtle to be represented experimentally at present. Secondly, the rate of secular climate change will not exceed background natural variability, on seasonal to interannual time-scales, for at least several decades – which may not provide the prevailing conditions of change, i.e. constancy, needed for phytoplankton adaptation. Taken together, the relatively subtle environmental changes, due to climate change, may result in adaptation by resident phytoplankton, but not for several decades due to the confounding effects of climate variability. This presents major challenges for the detection and attribution of climate change effects on Southern Ocean phytoplankton. We advocate the development of multi-faceted tests/metrics that will reflect the relative plasticity of different phytoplankton functional groups and/or species to respond to changing ocean conditions.

scholarly journals Stepwise Weakening of Aeolian Activities During the Holocene in the Gannan Region, Eastern Tibetan Plateau

2021 ◽  
Vol 9 ◽  
Author(s):  
Shengli Yang ◽  
Xiaojing Liu ◽  
Ting Cheng ◽  
Yuanlong Luo ◽  
Qiong Li ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Environmental Changes ◽  
Climatic Changes ◽  
Early Holocene ◽  
Eastern Tibetan Plateau ◽  
Aeolian Desertification ◽  
The Holocene ◽  
Aeolian Sediments ◽  
Aeolian Activity ◽  
History Of

Aeolian sediments hold key information on aeolian history and past environmental changes. Aeolian desertification and extensive land degradation have seriously affected the eco-environment in the Gannan region on the eastern Tibetan Plateau. Understanding the history of aeolian activities can deepen our understanding of the impacts of climatic changes on aeolian activities in the future. This study uses a detailed chronology and multiple proxy analyses of a typical aeolian section in Maqu to reconstruct aeolian activities in the region during the Holocene. Our results showed that aeolian activities have occurred in the eastern Tibetan Plateau since the early Holocene. Magnetic susceptibility, grain size records, and paleosols formation indicated a trend of stepwise weakening in aeolian activities from the early Holocene to the present. The weakening of aeolian activities was divided into three stages: ∼10.0–8.0 ka BP, ∼8.0–4.0 ka BP, and ∼4.0 ka BP to the present. Paleosols were primarily formed after ∼8.0 ka BP, and episodically interrupted aeolian activities processes in the Gannan region. Aeolian activity may increase in the Gannan region as the climate gradually warms. Climatic changes and local hydrological conditions have jointly affected the history of aeolian activities in this region.

scholarly journals Lake water dissolved inorganic carbon dynamics revealed from monthly measurements of radiocarbon in the Fuji Five Lakes, Japan

Elem Sci Anth ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Kosuke Ota ◽  
Yusuke Yokoyama ◽  
Yosuke Miyairi ◽  
Shinya Yamamoto ◽  
Toshihiro Miyajima
Keyword(s):  
Lake Water ◽  
Inorganic Carbon ◽  
Environmental Changes ◽  
Dissolved Inorganic Carbon ◽  
Anthropogenic Activities ◽  
Aquatic Organisms ◽  
Human Society ◽  
History Of ◽  
Lake Waters ◽  
Reservoir Age

Lakes are sensitive recorders of anthropogenic activities, as human society often develops in their vicinity. Lake sediments thus have been widely used to reconstruct the history of environmental changes in the past, anthropogenic, or otherwise, and radiocarbon dating provides chronological control of the samples. However, specific values of radiocarbon in different carbon reservoirs due to the different pathways of radiocarbon from the upper atmosphere to the lake, called the radiocarbon reservoir age, is always difficult to evaluate because of dynamic processes in and around lakes. There are few systematic studies on radiocarbon reservoir ages for lakes owing to the complex radiocarbon transfer processes for lakes. Here, we investigate lake waters of the Fuji Five Lakes with monthly monitoring of the radiocarbon reservoir effects. Radiocarbon from dissolved inorganic carbon (DIC) for groundwater and river water is also measured, with resulting concentrations (Δ14C) at their lowest at Lake Kawaguchi in August 2018 (–122.4 ± 3.2‰), and at their highest at Lake Motosu in January 2019 (–22.4 ± 2.5‰), despite a distance of 25 km. However, winter values in both lakes show similar trends of rising Δ14C (about 20‰). Our lake water DIC Δ14C results are compared to previously published records obtained from sediments in Lake Motosu and Lake Kawaguchi. These suggest that total organic carbon and compound-specific radiocarbon found in sediments are heavily influenced by summer blooms of aquatic organisms that fix DIC in water. Thus, future studies to conduct similar analyses at the various lakes would be able to provide further insights into the carbon cycle around inland water, namely understanding the nature of radiocarbon reservoir ages.

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