scholarly journals On the Shoulders of Giants: Continuing the Legacy of Large-Scale Ecosystem Manipulation Experiments in Puerto Rico

Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 210 ◽  
Author(s):  
Tana Wood ◽  
Grizelle González ◽  
Whendee Silver ◽  
Sasha Reed ◽  
Molly Cavaleri
Keyword(s):  
Puerto Rico ◽  
Tropical Forests ◽  
Large Scale ◽  
Field Experiments ◽  
Management Strategies ◽  
Luquillo Experimental Forest ◽  
Hurricane Disturbance ◽  
Wide Range ◽  
History Of ◽  
Forest Function

There is a long history of experimental research in the Luquillo Experimental Forest in Puerto Rico. These experiments have addressed questions about biotic thresholds, assessed why communities vary along natural gradients, and have explored forest responses to a range of both anthropogenic and non-anthropogenic disturbances. Combined, these studies cover many of the major disturbances that affect tropical forests around the world and span a wide range of topics, including the effects of forest thinning, ionizing radiation, hurricane disturbance, nitrogen deposition, drought, and global warming. These invaluable studies have greatly enhanced our understanding of tropical forest function under different disturbance regimes and informed the development of management strategies. Here we summarize the major field experiments that have occurred within the Luquillo Experimental Forest. Taken together, results from the major experiments conducted in the Luquillo Experimental Forest demonstrate a high resilience of Puerto Rico’s tropical forests to a variety of stressors.

scholarly journals Gefährlich und nützlich zugleich: Strategien zum Management der invasiven Robinie

2018 ◽  
Vol 169 (2) ◽  
pp. 77-85 ◽  
Author(s):  
Michaela Vítková ◽  
Marco Conedera ◽  
Jiří Sádlo ◽  
Jan Pergl ◽  
Petr Pyšek
Keyword(s):  
Time Management ◽  
Large Scale ◽  
Agricultural Landscape ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Management Strategies ◽  
Habitat Type ◽  
Agricultural Landscapes ◽  
Wide Range ◽  
Intensively Managed

Dangerous and useful at the same time: management strategies for the invasive black locust The North American black locust (Robinia pseudoacacia) is considered controversial as many other introduced tree species because of its both positive and negative properties. Based on a literature review and own data we analyze the occurrence of black locust in Czechia and Switzerland and present the management approaches in place. In both countries, black locust is on the blacklist of invasive introduced species. It can grow in a wide range of habitats from urban and agricultural landscape to dry grassland and forest. Meanwhile, the species became in many places part of the environment and human culture, so that neither unrestricted cultivation nor large-scale eradication is feasible. We suggest a context-dependent management which respects the different needs and takes into account the local environmental conditions, land-use, habitat type, risk of spread as well as economic, cultural and biodiversity aspects. To this purpose we propose three management strategies: 1) control respectively gradual suppression of black locust in forests where the species is not welcome, 2) its eradication in sensitive ecosystems as dry grasslands or clear and dry forests and 3) its tolerance in intensively managed agricultural landscapes and in urban environment.

Ivan Kavaleridze`s dramaturgy on the Sumy stage

2021 ◽  
Author(s):  
D.V. Budianskyi
Keyword(s):  
Large Scale ◽  
Musical Comedy ◽  
Historical Figures ◽  
Wide Range ◽  
Socialist Realist ◽  
History Of ◽  
Characteristic Features ◽  
Old Men ◽  
The Impact ◽  
First Time

The characteristic features of I. Kavaleridze’s drama is considered in the article. It is noted that there are signs of the artist’s individuality, attraction to expressionist forms, artistic techniques characteristic for the art of sculpture: symbolism, monumentality, hyperbole. I. Kavaleridze was well versed in the drama laws, understood the specifics of the stage events construction, had a large arsenal of literary means, thanks to which the characters’ monologues and dialogues were extremely expressive and colorful. In his work, he implemented original solutions that were ahead of time. Therefore, many of the artist’s ideas and achievements received due recognition only after his death. I. Kavaleridze’s creative heritage covers a wide range of both purely artistic and general philosophical problems. Among them the formation of the era of modernism and its features in the Ukrainian art of the early XX century, the impact of revolutionary ideas on the work of the 1920s, the role of spiritual leaders of the Ukrainian people T. Shevchenko and G. Skovoroda in the formation of national consciousness, political and ideological pressure on figurative art language and the formation of a socialist-realist canon, etc. The analysis of the productions of I. Kavalerizde’s plays “The First Furrow” and “Gregory and Paraskeva” on the stage of the Mykhailo Shchepkin Sumy Theater of Drama and Musical Comedy in 1970-1972. The article notes that these plays were staged in Sumy for the first time in the history of Ukrainian theater. The premiere of “The First Furrow” (the play was called “Old Men”) took place on March 19, 1970. The figure of the national genius Hryhoriy Skov oroda was als o embodied for the first time on t he stage in Sumy in th e play “Hryhoriy and Paraskeva”. It premiered on October 21, 1972. I. Rybchynsky, Honored Artist of the USSR, performed the production. Creating generalized historical outlines of people’s life, features of life at that time, depicting psychological portraits of people in various, sometimes-dramatic collisions, in the productions of I. Kavaleridze’s plays on the Sumy stage the emphasis was on universal values such as virtue, love. The main character was the Ukrainian people, who nurtured such large-scale historical figures, gave them strength and wisdom for great achievements. Based on publications in periodicals of that time, memoirs of Ukrainian directors, the peculiarities of the director’s interpretation, stenographic and musical design of these plays on the Sumy stage are considered. Considerable attention is paid to the analysis of acting works in I. Kavaleridze’s plays. In particular, the peculiarities of the actor’s embodiment of the image of the national genius Hryhoriy Skovoroda on the stage are presented. It is noted that I. Kavaleridze’s plays, created in a difficult political, social and ideological context, are rightly considered to be highly artistic works of Ukrainian drama. Their staging was carried out on various theatrical stages, including Mykhailo Shchepkin Sumy Theater of Drama and Musical Comedy is an important page of national theatrical art.

Hurricane Impacts in New England and Puerto Rico

2003 ◽  
Author(s):  
Emery R. Boose
Keyword(s):  
Puerto Rico ◽  
New England ◽  
Salt Water ◽  
Woody Debris ◽  
Wind Damage ◽  
River Channels ◽  
Fuel Loading ◽  
Luquillo Experimental Forest ◽  
The North ◽  
Hurricane Disturbance

Hurricanes have a profound effect on many coastal ecosystems. Direct impacts often include wind damage to trees, scouring and flooding of river channels, and salt-water inundation along shorelines (Simpson and Riehl 1981; Diaz and Pulwarty 1997). In some areas, secondary impacts may include landslides triggered by heavy rains (Scatena and Larson 1991) or catastrophic dry-season fires resulting from heavy fuel loading (Whigham in press). This chapter will focus on the longterm impacts of hurricane wind damage at two LTER sites, the Harvard Forest (HFR) in central New England and the Luquillo Experimental Forest (LUQ) in northeastern Puerto Rico. These two sites, both located in the North Atlantic hurricane basin and occasionally subject to the same storms, provide interesting examples of tropical and temperate hurricane disturbance regimes. Wind damage from a single hurricane is often highly variable (Foster 1988). Damage to individual trees can range from loss of leaves and fine branches, which can significantly alter surface nutrient inputs (Lodge et al. 1991), to bole snapping or uprooting, which can significantly alter coarse woody debris and soil microtopography (Carlton and Bazzaz 1998a and b). At the stand level, damage can range from defoliation to individual tree gaps to extensive blowdowns, creating different pathways for regeneration (Lugo 2000). At landscape and regional levels, complex patterns of damage are created by the interaction of meteorological, topographic, and biological factors (Boose et al. 1994). Adding to this spatial complexity is the fact that successive hurricanes are not necessarily independent in terms of their effects. A single storm lasting several hours may have effects that persist for decades (Foster et al. 1998). And forest susceptibility to wind damage is strongly influenced by composition and structure, which in turn are strongly influenced by previous disturbance history (Foster and Boose 1992). Thus, the impacts of a single hurricane may depend in part on the impacts of earlier storms as well as on other previous disturbances and land use. Hurricanes, like other disturbances, both create and respond to spatial heterogeneity (Turner et al. 2003). To understand the long-term ecological role of hurricanes at a given site, we must consider these three sets of questions: (1) What is the hurricane disturbance regime?

Orchid—phorophyte relationships in a forest watershed in Puerto Rico

1993 ◽  
Vol 9 (2) ◽  
pp. 231-240 ◽  
Author(s):  
Luis E. Migenis ◽  
James D. Ackerman
Keyword(s):  
Puerto Rico ◽  
Large Scale ◽  
Abundant Species ◽  
Luquillo Experimental Forest ◽  
Orchid Species ◽  
Host Trees ◽  
Dacryodes Excelsa ◽  
Abundance And Diversity ◽  
Guarea Guidonia ◽  
Tropical Watershed

ABSTRACTOrchid diversity, distribution and host specificity were examined in a tropical watershed in the Luquillo Experimental Forest of Puerto Rico. Eleven orchid species occur in the area. The low diversity is attributed to island isolation and large-scale hurricane disturbances. Pleurothallis ruscifolia and Maxillaria coccinea were by far the most abundant species in the area and occurred on the largest number of host species and host zones. None of the orchids were host specific or host zone specialists although preferences for hosts and vertical host zones were encountered.Only 8.2% of the 426 trees and shrubs and 24.4% of the 45 species surveyed were orchid phorophytes (= hosts). Examination of host distribution by diameter at breast height (DBH) showed that 80.5% were greater than 16 cm DBH. Orchid species in the area tend to occur on rough bark hosts, but their preferences are not statistically significant. Guarea guidonia (Meliaceae) and Dacryodes excelsa (Burseraceae) are the two most important orchid hosts in our study site comprising 62.9% of all host trees. Careful management of these two tree species is suggested, since these species may be crucial to the maintenance of orchid abundance and diversity in the area.

scholarly journals A large-scale forest fragmentation experiment: the Stability of Altered Forest Ecosystems Project

2011 ◽  
Vol 366 (1582) ◽  
pp. 3292-3302 ◽  
Author(s):  
Robert M. Ewers ◽  
Raphael K. Didham ◽  
Lenore Fahrig ◽  
Gonçalo Ferraz ◽  
Andy Hector ◽  
...  
Keyword(s):  
Forest Fragmentation ◽  
Large Scale ◽  
Forest Cover ◽  
Forest Ecosystems ◽  
Field Experiments ◽  
Spatial Scales ◽  
Ecological Impacts ◽  
Data Types ◽  
Wide Range ◽  
The Stability

Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification.

scholarly journals Sir George Gabriel Stokes, Bart (1819–1903): his impact on science and scientists

2020 ◽  
Vol 378 (2174) ◽  
pp. 20190524
Author(s):  
Paul Ranford
Keyword(s):  
Royal Society ◽  
Large Scale ◽  
Stokes Equations ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Victorian Era ◽  
Wide Range ◽  
History Of ◽  
And Mathematics ◽  
Lord Kelvin

Lucasian Professor Sir George Gabriel Stokes was appointed joint-Secretary of the Royal Society in 1854, a post he held for the unprecedented period of 31 years, relinquishing the role when he succeeded T.H. Huxley as President in 1885. An eminent scientist of the Victorian era, Stokes explained fluorescence (he also coined the word) and his hydrodynamical formulae (the ‘Navier–Stokes equations’) remain ubiquitous today in the physics of any phenomenon involving fluid flows, from pipelines to glaciers to large-scale atmospheric perturbations. He also made seminal advances in optics and mathematics, and formulae that bear his name remain widely used today. The historiography however appears to understate Stokes's significant impact on science as unacknowledged collaborator on a wide range of scientific developments. His scientific peers regarded him as a mentor, advisor, designer of crucial experiments and, as editor of the Royal Society's scientific journals, arbiter of the standards of excellence in scientific communication to be attained before publication would be considered. Three brief case studies on Stokes's correspondence with Lord Kelvin, Sir William Crookes and the chemist Arthur Smithells exemplify how his impact was conveyed through the work of other scientists. This paper also begins consideration of why the character and worldview of Stokes led him to eschew personal reputation and profit for the sake of science and the Royal Society, and of how the development of the discipline of history of science has impacted on historiography relating to Stokes and others. This article is part of the theme issue ‘Stokes at 200 (Part 1)’.

Local Lives, Parallel Histories

2020 ◽  
Author(s):  
Marcel Thomas
Keyword(s):  
Social Change ◽  
Life Histories ◽  
Large Scale ◽  
Postwar Germany ◽  
Wide Range ◽  
History Of ◽  
Local Meaning ◽  
Economic Developments ◽  
The Cold War ◽  
Oral History Interviews

The division of Germany separated a nation, divided communities, and inevitably shaped the life histories of those growing up in the socialist dictatorship of the East and the liberal democracy of the West. This peculiarly German experience of the Cold War has so far mostly been seen through the lens of the divided Berlin or other border communities. What has been much less explored, however, is what division meant to the millions of Germans in East and West who lived far away from the Wall and the centres of political power. This book is the first comparative study to examine how villagers in both Germanies dealt with the imposition of two very different systems in their everyday lives. Focusing on two villages, Neukirch (Lausitz) in Saxony and Ebersbach (Fils) in Baden-Württemberg, it explores how local residents experienced and navigated social change in their localities in the postwar era. Based on a wide range of archival sources as well as oral history interviews, the book argues that there are parallel histories of responses to social change among villagers in postwar Germany. Despite the different social, political, and economic developments, the residents of both localities desired rural modernization, lamented the loss of ‘community’, and became politically active to control the transformation of their localities. The book thereby offers a bottom-up history of the divided Germany which shows how individuals on both sides of the Wall gave local meaning to large-scale processes of change.

scholarly journals Sensitivity of pelagic calcification to ocean acidification

2011 ◽  
Vol 8 (2) ◽  
pp. 433-458 ◽  
Author(s):  
R. Gangstø ◽  
F. Joos ◽  
M. Gehlen
Keyword(s):  
Ocean Acidification ◽  
Carbon Emissions ◽  
Large Scale ◽  
Field Experiments ◽  
Emission Scenario ◽  
Atmospheric Co2 ◽  
Soluble Form ◽  
Saturation State ◽  
Biogeochemical Models ◽  
Wide Range

Abstract. Ocean acidification might reduce the ability of calcifying plankton to produce and maintain their shells of calcite, or of aragonite, the more soluble form of CaCO3. In addition to possibly large biological impacts, reduced CaCO3 production corresponds to a negative feedback on atmospheric CO2. In order to explore the sensitivity of the ocean carbon cycle to increasing concentrations of atmospheric CO2, we use the new biogeochemical Bern3D/PISCES model. The model reproduces the large scale distributions of biogeochemical tracers. With a range of sensitivity studies, we explore the effect of (i) using different parameterizations of CaCO3 production fitted to available laboratory and field experiments, of (ii) letting calcite and aragonite be produced by auto- and heterotrophic plankton groups, and of (iii) using carbon emissions from the range of the most recent IPCC Representative Concentration Pathways (RCP). Under a high-emission scenario, the CaCO3 production of all the model versions decreases from ~1 Pg C yr−1 to between 0.36 and 0.82 Pg C yr−1 by the year 2100. The changes in CaCO3 production and dissolution resulting from ocean acidification provide only a small feedback on atmospheric CO2 of −1 to −11 ppm by the year 2100, despite the wide range of parameterizations, model versions and scenarios included in our study. A potential upper limit of the CO2-calcification/dissolution feedback of −30 ppm by the year 2100 is computed by setting calcification to zero after 2000 in a high 21st century emission scenario. The similarity of feedback estimates yielded by the model version with calcite produced by nanophytoplankton and the one with calcite, respectively aragonite produced by mesozooplankton suggests that expending biogeochemical models to calcifying zooplankton might not be needed to simulate biogeochemical impacts on the marine carbonate cycle. The changes in saturation state confirm previous studies indicating that future anthropogenic CO2 emissions may lead to irreversible changes in ΩA for several centuries. Furthermore, due to the long-term changes in the deep ocean, the ratio of open water CaCO3 dissolution to production stabilizes by the year 2500 at a value that is 30–50% higher than at pre-industrial times when carbon emissions are set to zero after 2100.

scholarly journals African genomes illuminate the early history and transition to selfing in Arabidopsis thaliana

2017 ◽  
Vol 114 (20) ◽  
pp. 5213-5218 ◽  
Author(s):  
Arun Durvasula ◽  
Andrea Fulgione ◽  
Rafal M. Gutaker ◽  
Selen Irez Alacakaptan ◽  
Pádraic J. Flood ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Large Scale ◽  
Molecular Model ◽  
Genomic Analysis ◽  
Geographic Region ◽  
Early History ◽  
Sub Saharan Africa ◽  
Last Interglacial ◽  
Wide Range ◽  
History Of

Over the past 20 y, many studies have examined the history of the plant ecological and molecular model, Arabidopsis thaliana, in Europe and North America. Although these studies informed us about the recent history of the species, the early history has remained elusive. In a large-scale genomic analysis of African A. thaliana, we sequenced the genomes of 78 modern and herbarium samples from Africa and analyzed these together with over 1,000 previously sequenced Eurasian samples. In striking contrast to expectations, we find that all African individuals sampled are native to this continent, including those from sub-Saharan Africa. Moreover, we show that Africa harbors the greatest variation and represents the deepest history in the A. thaliana lineage. Our results also reveal evidence that selfing, a major defining characteristic of the species, evolved in a single geographic region, best represented today within Africa. Demographic inference supports a model in which the ancestral A. thaliana population began to split by 120–90 kya, during the last interglacial and Abbassia pluvial, and Eurasian populations subsequently separated from one another at around 40 kya. This bears striking similarities to the patterns observed for diverse species, including humans, implying a key role for climatic events during interglacial and pluvial periods in shaping the histories and current distributions of a wide range of species.

scholarly journals FACTORS AFFECTING THE SUCROSE CONTENT OF SUGARCANE: FERTILIZERS

1969 ◽  
Vol 36 (3) ◽  
pp. 194-202
Author(s):  
G. Samuels ◽  
M. A. Lugo López ◽  
P. Landrau Jr.
Keyword(s):  
Puerto Rico ◽  
Field Experiments ◽  
Sucrose Concentration ◽  
Nitrogen Sources ◽  
Minor Element ◽  
Percentage Increase ◽  
Sucrose Content ◽  
Factors Affecting ◽  
Wide Range ◽  
Percentage Yield

The results of over 150 field experiments with sugarcane conducted by the Agricultural Experiment Station of the University of Puerto Rico covering a wide range of varieties and soils of Puerto Rico revealed the following: 1. Nitrogen produced an increase in sucrose content with increased cane yields. When the percentage increase in cane tonnage is plotted against the percentage increase in sucrose percent cane, a highly significant regression is obtained. The equation obtained reveals that a significant increase in sucrose concentration occurs only after increases in yields are over 27 percent. 2. Different nitrogen sources, namely, ammonium nitrate, ammonium sulfate, and Uramon, produced no significant differences in influence on sucrose concentrations. 3. The application of phosphorus had no significant effect on the sucrose content of sugarcane. Cane tonnage responses were also slight. 4. The use of potassium fertilizers did not significantly influence the sucrose content of sugarcane. Where there was an increase in yield, there was generally an increase in sucrose content. Percentage increases in yield of cane, however, were very low, the majority being less than 10 percent. The soils seem to contain sufficient potassium for good sucrose concentrations, and the use of potash as fertilizer does not usually produce any significant increases in sucrose. 5. The minor-element fertilizers produced no significant increases in sucrose content. The use of copper, magnesium, zinc, boron, manganese, calcium, sodium, iron, and sulfur produced no appreciable increases in yield. The majority of percentage yield increases were less than 7, while percentage decreases or increases in sucrose content varied from —3 to +7.

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