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Full-Text Articles in Life Sciences

A Fused Radar–Optical Approach For Mapping Wetlands And Deepwaters Of The Mid–Atlantic And Gulf Coast Regions Of The United States, Brian T. Lamb, Maria A. Tzortziou, Kyle C. Mcdonald Jun 2021

A Fused Radar–Optical Approach For Mapping Wetlands And Deepwaters Of The Mid–Atlantic And Gulf Coast Regions Of The United States, Brian T. Lamb, Maria A. Tzortziou, Kyle C. Mcdonald

Publications and Research

Tidal wetlands are critically important ecosystems that provide ecosystem services including carbon sequestration, storm surge mitigation, water filtration, and wildlife habitat provision while supporting high levels of biodiversity. Despite their importance, monitoring these systems over large scales remains challenging due to difficulties in obtaining extensive up-to-date ground surveys and the need for high spatial and temporal resolution satellite imagery for effective space-borne monitoring. In this study, we developed methodologies to advance the monitoring of tidal marshes and adjacent deepwaters in the Mid-Atlantic and Gulf Coast United States. We combined Sentinel-1 SAR and Landsat 8 optical imagery to classify marshes and …


Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce Apr 2020

Investigation Of An Elevational Gradient Reveals Strong Differences Between Bacterial And Eukaryotic Communities Coinhabiting Nepenthes Phytotelmata, Kadeem J. Gilbert, Leonora S. Bittleston, Mark Arcebal K. Naive, Anthony E. Kiszewski, Perry Archival C. Buenavente, David J. Lohman, Naomi E. Pierce

Publications and Research

Elevation is an important determinant of ecological community composition. It integrates several abiotic features and leads to strong, repeatable patterns of community structure, including changes in the abundance and richness of numerous taxa. However, the influence of elevational gradients on microbes is understudied relative to plants and animals. To compare the influence of elevation on multiple taxa simultaneously, we sampled phytotelm communities within a tropical pitcher plant (Nepenthes mindanaoensis) along a gradient from 400 to 1200 m a.s.l. We use a combination of metabarcoding and physical counts to assess diversity and richness of bacteria, micro-eukaryotes, and arthropods, and compare the …


Spatial Upscaling Of Forest Response To Drought, Wei Fang, Peipei Xu, Tao Zhao, Xiang Zhao, Hui Luo, George Hendrey, Chuixiang Yi Oct 2019

Spatial Upscaling Of Forest Response To Drought, Wei Fang, Peipei Xu, Tao Zhao, Xiang Zhao, Hui Luo, George Hendrey, Chuixiang Yi

Publications and Research

We have integrated the observational capability of satellite remote sensing with plot-scale tree ring data to up-scale the evaluation of forest responses to drought. Satellite data, such as Normalized Difference Vegetation Index (NDVI), can provide a spatially continuous measure with limited temporal coverage, while tree Ring Width Index (RWI) provides accurate assessment with much longer time series local scales. Here, we explored the relationship between RWI and NDVI of three dominant species in the Southwestern United States (SWUS), and predicted RWI spatial distribution from 2001 to 2017 based on MODIS 1-km resolution NDVI data with stringent quality control. We detected …


Local Adaptation In Mainland Anole Lizards: Integrating Population History And Genome–Environment Associations, Ivan Prates, Anna Penna, Miguel Trefaut Rodrigues, Ana Carolina Carnaval Nov 2018

Local Adaptation In Mainland Anole Lizards: Integrating Population History And Genome–Environment Associations, Ivan Prates, Anna Penna, Miguel Trefaut Rodrigues, Ana Carolina Carnaval

Publications and Research

Environmental gradients constrain physiological performance and thus species’ ranges, suggesting that species occurrence in diverse environments may be associated with local adaptation. Genome–environment association analyses (GEAA) have become central for studies of local adaptation, yet they are sensitive to the spatial orientation of historical range expansions relative to landscape gradients. To test whether potentially adaptive genotypes occur in varied climates in wide‐ranged species, we implemented GEAA on the basis of genomewide data from the anole lizards Anolis ortonii and Anolis punctatus, which expanded from Amazonia, presently dominated by warm and wet settings, into the cooler and less rainy Atlantic …


Forest Drought Resistance Distinguished By Canopy Height, Wei Fang, Peipei Xu, Tao Zhou, George Hendrey, Xiang Zhao Jun 2018

Forest Drought Resistance Distinguished By Canopy Height, Wei Fang, Peipei Xu, Tao Zhou, George Hendrey, Xiang Zhao

Publications and Research

How are the survival and growth of trees under severe drought affected by their size? While some studies have shown that large trees are more vulnerable to drought than smaller trees, others found that small trees are the more vulnerable. We explored the potential relationships between canopy height and forest responses to drought indicated by tree mortality, tree ring width index (RWI), and normalized difference vegetation index (NDVI) in the southwestern United States (SWUS) in 2002. In that year many trees had zero tree ring growth due to mortality and dieback, presumably related to drought-stress. With RWI data from a …


Dynamic Responses Of Tree-Ring Growth To Multiple Dimensions Of Drought, Wei Fang, Shan Gao, Ruishun Liu, Tao Zhou, Chuixiang Yi, Ruijie Liu, Xiang Zhao, Hui Luo Jun 2018

Dynamic Responses Of Tree-Ring Growth To Multiple Dimensions Of Drought, Wei Fang, Shan Gao, Ruishun Liu, Tao Zhou, Chuixiang Yi, Ruijie Liu, Xiang Zhao, Hui Luo

Publications and Research

Droughts, which are characterized by multiple dimensions including frequency, duration, severity and onset timing, can impact tree growth profoundly. Different dimensions of drought influence tree growth independently or jointly, which makes the development of accurate predictions a formidable challenge. Measurement-based tree-ring data have obvious advantages for studying the drought responses of trees. Here, we explored the use of abundant tree-ring records for quantifying regional response patterns to key dimensions of drought. Specifically, we designed a series of regional-scaled “natural experiments”, based on 357 tree-ring chronologies from Southwest USA and location-matched monthly water balance anomalies, to reveal how tree-ring growth responds …


Bifurcated Response Of A Regional Forest To Drought, Wei Fang, Chuixiang Yi, Guangwei Mu, George Hendrey, Sergio M. Vicente-Serrano, Tao Zhou, Shan Gao, Peipei Xu Apr 2018

Bifurcated Response Of A Regional Forest To Drought, Wei Fang, Chuixiang Yi, Guangwei Mu, George Hendrey, Sergio M. Vicente-Serrano, Tao Zhou, Shan Gao, Peipei Xu

Publications and Research

Several lines of evidence suggest that forest growth in many regions is declining as a consequence of changing climate. To predict the fate of forests in the future, a quantitative understanding of how the key climate variables (insolation, precipitation and temperature) interact with forests to cause the decline is a pressing need. Here we use a regionally-averaged tree-ring width index (RWIr ) to quantify forest growth in the Southwest United States (SWUS). We show that over a period of 100 years, SWUS RWIr bifurcated into forest stands with enhanced (healthy) and reduced (declining) branches when regressed on shortwave-radiation and temperature, …


A Novel Three-Way Interaction Among A Fish, Algae, And A Parasitic Copepod, John Waldman Dec 2017

A Novel Three-Way Interaction Among A Fish, Algae, And A Parasitic Copepod, John Waldman

Publications and Research

No abstract provided.


Cryptic Diversity And Discordance In Single‐Locus Species Delimitation Methods Within Horned Lizards (Phrynosomatidae: Phrynosoma), Christopher Blair, Robert W. Bryson Jr. Nov 2017

Cryptic Diversity And Discordance In Single‐Locus Species Delimitation Methods Within Horned Lizards (Phrynosomatidae: Phrynosoma), Christopher Blair, Robert W. Bryson Jr.

Publications and Research

Biodiversity reduction and loss continues to progress at an alarming rate, and thus there is widespread interest in utilizing rapid and efficient methods for quantifying and delimiting taxonomic diversity. Single-locus species-delimitation methods have become popular, in part due to the adoption of the DNA barcoding paradigm. These techniques can be broadly classified into tree-based and distance-based methods depending on whether species are delimited based on a constructed genealogy. Although the relative performance of these methods has been tested repeatedly with simulations, additional studies are needed to assess congruence with empirical data. We compiled a large data set of mitochondrial ND4 …


Biodiversity Of Medicinal Plants In The Highlands: Problems And Perspectives, Vyacheslav Dushenkov Jul 2016

Biodiversity Of Medicinal Plants In The Highlands: Problems And Perspectives, Vyacheslav Dushenkov

Publications and Research

Climate change is affecting medicinal plants around the world and could ultimately lead to losses of some key species, in particular species endemic to a region and causing plants to migrate to new ranges. As the situation unfolds, climate change may become a pressing issue for the herbal community, affecting medicinal plant supply chains with varying requirements for plant cultivation, resource management in the wild, harvesting, processing, and importantly marketing.


Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy Jun 2016

Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy

Publications and Research

The two largest lakes on the Caribbean Island of Hispaniola, Lake Azuei in Haiti and Lake Enriquillo in the Dominican Republic, have experienced dramatic growth and surface area expansion over the past few years leading to severe flooding and loss of arable land around the lake perimeters. In order to better understand the reasons for this unprecedented rate of expansion and the resulting consequences a multi-disciplinary team comprised of researchers from Haiti, the DR, and the US have embarked on an extensive data collecting and hydrologic and climatological modeling campaign. While the sensor deployment entails stations that measure climatological data …


Biofluorescence In Catsharks (Scyliorhinidae): Fundamental Description And Relevance For Elasmobranch Visual Ecology, David F. Gruber, Ellis R. Loew, Dimitri D. Deheyn, Derya Akkaynak, Jean P. Gaffney, W. Leo Smith, Matthew P. Davis, Jennifer H. Stern, Vincent A. Pieribone, John S. Sparks Apr 2016

Biofluorescence In Catsharks (Scyliorhinidae): Fundamental Description And Relevance For Elasmobranch Visual Ecology, David F. Gruber, Ellis R. Loew, Dimitri D. Deheyn, Derya Akkaynak, Jean P. Gaffney, W. Leo Smith, Matthew P. Davis, Jennifer H. Stern, Vincent A. Pieribone, John S. Sparks

Publications and Research

Biofluorescence has recently been found to be widespread in marine fishes, including sharks. Catsharks, such as the Swell Shark (Cephaloscyllium ventriosum) from the eastern Pacific and the Chain Catshark (Scyliorhinus retifer) from the western Atlantic, are known to exhibit bright green fluorescence. We examined the spectral sensitivity and visual characteristics of these reclusive sharks, while also considering the fluorescent properties of their skin. Spectral absorbance of the photoreceptor cells in these sharks revealed the presence of a single visual pigment in each species. Cephaloscyllium ventriosum exhibited a maximum absorbance of 484 ± 3 nm and an absorbance range at half …


Striking The Balance: Challenges And Perspectives For The Protected Areas Network In Northeastern European Russia, Svetlana V. Degteva, Vasily I. Ponomarev, Sasha W. Eisenman, Vyacheslav Dushenkov Jan 2015

Striking The Balance: Challenges And Perspectives For The Protected Areas Network In Northeastern European Russia, Svetlana V. Degteva, Vasily I. Ponomarev, Sasha W. Eisenman, Vyacheslav Dushenkov

Publications and Research

Increasing anthropogenic pressure on the largest remaining tracts of old-growth boreal forest in Europe necessitates additional conservation of ecosystems and biodiversity in northeastern European Russia. In a regional network comprising 8 % of the Nenets Autonomous District and 13.5 % of the Komi Republic, 248 areas have varying protected statuses as state nature reserves (zapovedniks), national parks, reserves/sanctuaries (zakazniks), or natural monuments. Due to increased natural resource extraction in this relatively pristine area, designation of additional protected areas is critical for the protection of key ecological sites. The history of ecological preservation in these regions is herein described, and recent …


Notes On The Diet Of The Malay Civet (Viverra Tangalunga) And Other Civets In Logged And Unlogged Lowland Dipterocarp Rain Forests In Sabah, Borneo, Christina P. Colon, John B. Sugau Jan 2012

Notes On The Diet Of The Malay Civet (Viverra Tangalunga) And Other Civets In Logged And Unlogged Lowland Dipterocarp Rain Forests In Sabah, Borneo, Christina P. Colon, John B. Sugau

Publications and Research

Civet diets were examined in a logged and unlogged Bornean rain forest. Malay civets (Viverra tangalunga) consumed invertebrates, fruit, rodents, insectivores, birds, snakes and lizards, and appear to show preference for centipedes and scorpions. Other civet species consumed fruit, such as figs, Connarus sp. and Annona sp., particularly in the unlogged forest, but also consumed invertebrates and vertebrates. Reduced fruit consumption observed in the logged forest may be due to lower availability and may be offset by increased consumption of invertebrates. The increased overlap in diet between Malay civets and other civets in disturbed areas may lead to …


The Fourth Level Of Social Structure In A Multi-Level Society: Ecological & Social Functions Of Clans In Hamadryas Baboons, Amy Schreier, Larissa Swedell Jan 2009

The Fourth Level Of Social Structure In A Multi-Level Society: Ecological & Social Functions Of Clans In Hamadryas Baboons, Amy Schreier, Larissa Swedell

Publications and Research

Hamadryas baboons are known for their complex, multi-level social structure consisting of troops, bands, and one-male units (OMUs) [Kummer, 1968]. Abegglen [1984] observed a 4th level of social structure comprising several OMUs that rested near one another on sleeping cliffs, traveled most closely together during daily foraging, and sometimes traveled as subgroups independently from the rest of the band. Abegglen called these associations “clans” and suggested that they consisted of related males. Here we confirm the existence of clans in a second wild hamadryas population, a band of about 200 baboons at the Filoha site in lowland Ethiopia. During …


Use Of Palm Trees As A Sleeping Site By Hamadryas Baboons In Ethiopia, Amy Schreier, Larissa Swedell Jan 2008

Use Of Palm Trees As A Sleeping Site By Hamadryas Baboons In Ethiopia, Amy Schreier, Larissa Swedell

Publications and Research

Hamadryas baboons sleep on cliffs throughout their range, and this can be attributed to the safety cliffs provide against predators in the absence of tall trees. In this paper, we report the first documented occurrence of hamadryas baboons sleeping in doum palm trees rather than on cliffs. Data derive from a study of hamadryas baboons at the Filoha site in lowland Ethiopia. During all-day follows, data were collected on travel patterns, band activity, and location. Variation in the baboons’ home range was characterized using vegetation transects. We discovered that one band in this population, Band 3, occasionally slept in doum …


Composition And Seasonality Of Diet In Wild Hamadryas Baboons: Preliminary Findings From Filoha, Larissa Swedell, Getenet Hailemeskel, Amy Schreier Jan 2008

Composition And Seasonality Of Diet In Wild Hamadryas Baboons: Preliminary Findings From Filoha, Larissa Swedell, Getenet Hailemeskel, Amy Schreier

Publications and Research

Here we report the first year-round quantitative data on dietary composition and seasonality in wild hamadryas baboons. Study subjects were adult male members of Band 3 at the Filoha field site in central lowland Ethiopia. Data collection consisted of 10-minute focal samples during all-day follows 4-6 days per month over the course of one year. The two largest contributors to the diet were Hyphaene thebaica and Acacia senegal, and these were the only plant species found in the diet during every month of the year. Other relatively major contributors to the diet, such as Cyperus grandibulbosus, Seddera bagshawei, …


Perspectives On Reproduction And Life History In Baboons, Larissa Swedell, Steven R. Leigh Jan 2006

Perspectives On Reproduction And Life History In Baboons, Larissa Swedell, Steven R. Leigh

Publications and Research

No abstract provided.


Strategies Of Sex And Survival In Hamadryas Baboons: Through A Female Lens, Larissa Swedell Jan 2006

Strategies Of Sex And Survival In Hamadryas Baboons: Through A Female Lens, Larissa Swedell

Publications and Research

No abstract provided.


Iniciativas De Manejo Costero En Venezuela, Aldemaro Romero Jr. Jan 1990

Iniciativas De Manejo Costero En Venezuela, Aldemaro Romero Jr.

Publications and Research

No abstract provided.