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Articles 2611 - 2640 of 3965

Full-Text Articles in Ecology and Evolutionary Biology

Coarse Woody Debris In A Tropical Rainforest In North Queensland, Australia: Relationships With Stand Structure And Disturbance, Nadine Rea Apr 2012

Coarse Woody Debris In A Tropical Rainforest In North Queensland, Australia: Relationships With Stand Structure And Disturbance, Nadine Rea

Independent Study Project (ISP) Collection

Coarse woody debris (CWD) refers to the woody material on the forest floor, including fallen stems, large branches, coarse roots, wood pieces, and standing dead trees (snags) (Harmon et al. 1986). CWD is an essential but often overlooked aspect of ecosystems. It plays many key ecosystem roles and is instrumental in overall ecosystem functionality. While a piece of CWD decomposes, it provides key habitat for many different species, minimizes soil erosion, affects soil development, stores nutrients and water, and influences the global carbon cycle (Harmon and Hua 1991). In some forests, CWD can exist on the forest floor for hundreds …


Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible Apr 2012

Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean …


Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2012 To March 31, 2012, Margaret N. Rees Mar 2012

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2012 To March 31, 2012, Margaret N. Rees

Get Outdoors Nevada

  • The number of records in the volunteer database increased by 4.96% over the last quarter. The database now contains 7,423 records.
  • Results show an average of 1,259 visits per month, and with an average of 3,015 pages viewed per month.
  • Get Outdoors Nevada supported 14 volunteer events in a variety of ways. These events utilized 364 volunteers whom contributed approximately 2,414 hours of service.
  • Three community outreach events were attended, resulting in 293 direct contacts with 50 names added to the database.
  • The automated volunteer orientation training project has been completed and disks have been delivered to the 4 agencies. …


Operational And Compliance Elements Of A New Management Plan For The West Coast Rock Lobster Managed Fishery. A Discussion Paper., Department Of Fisheries Western Australia Feb 2012

Operational And Compliance Elements Of A New Management Plan For The West Coast Rock Lobster Managed Fishery. A Discussion Paper., Department Of Fisheries Western Australia

Fisheries Management Papers

This paper was prepared to set out the proposed direction for compliance and other operational matters under a new management plan for the West Coast Rock Lobster Managed Fishery (the new Management Plan) which is expected to commence operation on 15 January 2013. It is one of two papers being released by the Department of Fisheries (Department) for comment as part of consultation on the development of this legislation, and is designed to encourage public involvement in the changes to the management arrangements for the West Coast Rock Lobster Managed Fishery (the fishery).


Some Biogeographers, Evolutionists And Ecologists: Chrono-Biographical Sketches, Charles H. Smith, Joshua Woleben, Carubie Rodgers Jan 2012

Some Biogeographers, Evolutionists And Ecologists: Chrono-Biographical Sketches, Charles H. Smith, Joshua Woleben, Carubie Rodgers

DLPS Faculty Publications

Each name in the following list of naturalists is linked to a corresponding capsule "chrono-biographical" sketch of that individual prepared by the authors. Coverage extends from approximately 1950 backward in time as far as the eighteenth century; figures from all over the world are included (though there is admittedly a decided Anglo-American bias). The target subject here is biogeography, but this being a broad field there are many persons on the list who are better known as climatologists, zoologists, botanists, ecologists, oceanographers, paleontologists, etc.--in other words, who made their main reputations in cognate disciplines.

This service has been set up …


Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz Jan 2012

Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


The Kennebec River: A Historic Maine Resource, Elise Begin Jan 2012

The Kennebec River: A Historic Maine Resource, Elise Begin

Historical Ecology Atlas of New England

The Kennebec River has been considered one of Maine’s most important resources for at least the past 6-8 thousand years; its basin is located in west central Maine and drains 5,893 square miles, an area that is approximately one-fifth the area of the state. The river originates at Moosehead lake and runs 170 miles to the Atlantic Ocean. The river can be divided into two basins: the upper basin, which spans from Moosehead Lake to Waterville; and the lower basin, which spans from Waterville to the ocean.

Before the arrival of Europeans in 1606, the Abenaki Indians controlled the entirety …


Bath, Maine: A City Of Ships, Taylor Witkin Jan 2012

Bath, Maine: A City Of Ships, Taylor Witkin

Historical Ecology Atlas of New England

Known as Maine’s city of ships, Bath sits on the shores of the Kennebec River, about 15 miles from the Gulf of Maine and 40 miles up the coast from Portland. Though small in population, Bath’s impact on Maine, the rest of United States, and even on the world has been anything but small. Today Bath is known mostly for the Bath Iron Works, which supplies the US Navy with a large portion of its fleets, however, in Bath’s early days it built large, wooden yachts and schooners mostly for trade, not war. The next few pages will explore Bath’s …


The Happy Valley, Cassie Raker Jan 2012

The Happy Valley, Cassie Raker

Historical Ecology Atlas of New England

On the Connecticut River in Western Massachusetts, there exists the Happy Valley. Surrounded by the humble Holyoke Range, today you will find a bustling New England settlement dominated by local colleges and universities. But it was not always so. The picturesque Mount Holyoke and its accompanying hotel, known as the Summit House, have overlooked the area for hundreds of years, watching it change from forest to farmland to industry to the modern landscape it is today.


Rural Inhabitant Perceptions Of Sandhill Cranes In Wintering Areas Of Northern Mexico, Ingrid Barcelo, Juan Carlos Guzmán-Aranda, Felipe Chávez-Ramírez, Larkin A. Powell Jan 2012

Rural Inhabitant Perceptions Of Sandhill Cranes In Wintering Areas Of Northern Mexico, Ingrid Barcelo, Juan Carlos Guzmán-Aranda, Felipe Chávez-Ramírez, Larkin A. Powell

School of Natural Resources: Faculty Publications

Trends in the mid-continent population of sandhill cranes (Grus canadensis) indicate that the species is increasing. A large proportion of this population winters in northern Mexico where possible conflicts between local inhabitants and cranes can occur. We conducted interviews of 40 rural inhabitants living near wetlands used by cranes in three Mexican states. All interviewees had knowledge of cranes and were capable of describing them. The arrival of cranes affected 43% of interviewees. The negative effects were mainly destroyed crops with a subsequent diminished production. Seventy percent of those affected implemented scare tactics to deter the birds, while others (15%) …


The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold Jan 2012

The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen Jan 2012

Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Magnitude And Structure Of Lymantria Dispar Asiatica Infestations Of Common Forest Steppe Tree Species In Northern Mongolia, Nina Tiralla, Kai Füldner, Stefan Schütz Jan 2012

Magnitude And Structure Of Lymantria Dispar Asiatica Infestations Of Common Forest Steppe Tree Species In Northern Mongolia, Nina Tiralla, Kai Füldner, Stefan Schütz

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Lymantria dispar L. is one of the most serious forest pests worldwide by infesting large forest areas involving massive tree dieback. Unlike outbreaks of Lymantria dispar L. in Germany that cause massive defoliation, observations of outbreaks of Lymantria dispar asiatica made in the research area Khonin Nuga, West Khentii, Mongolia during the past six years showed only punctual defoliation, and dieback was extremely scarce. However, information on the performance of Lymantria dispar asiatica and the corresponding reaction of host tree species in Khonin Nuga is rare. Therefore, this study concentrates on the examination of primarily affected tree species and the …


Diversity And Community Pattern Of Darkling Beetles (Coleoptera: Tenebrionidae) Along An Ecological Gradient In Arid Mongolia, M. Pfeiffer, E. Bayannasan Jan 2012

Diversity And Community Pattern Of Darkling Beetles (Coleoptera: Tenebrionidae) Along An Ecological Gradient In Arid Mongolia, M. Pfeiffer, E. Bayannasan

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

One of the most conspicuous detrito- and phytodetritophagous groups of beetles in the Asian steppes and deserts is the family Tenebrionidae (Coleoptera, Polyphaga) (KONSTANTINOV et al. 2009). Mongolia harbors a rich diversity of these beetles with 215 species and 50 genera of Tenebrionidae listed for the country (MEDVEDEV 1990), many of them restricted to its arid parts, where they obtain high abundances and dominate – together with ants – the insect soil fauna (PFEIFFER et al. 2003). Their dark color may be a means to withstand the high radiation at daytime; however, a large number of species is night active …


Comparative Study Of Constituents Of Essential Oils Of Ocimum Basilicum L. Cultivated In The Mongolian Gobi, Shataryn Altantsetseg, Sandui Shatar, N. Javzmaa Jan 2012

Comparative Study Of Constituents Of Essential Oils Of Ocimum Basilicum L. Cultivated In The Mongolian Gobi, Shataryn Altantsetseg, Sandui Shatar, N. Javzmaa

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The essential oils of the herb Ocimum basilicum L., cultivated in the Mongolian Gobi, have been examined. Oils were isolated by hydro-distillation and analyzed by GC-MS. The principle components of Common Basil were methyl chavicol (52.1 %), linalool (23.9 %). In the oils of the different varieties of Basil were the following compounds found: Sweet Basil: linalool (24.5–27.4 %), methyl chavicol (19.8–20.0 %), bergamotene (10.0 %), 1.8-cineole (8.5 %); Purple Basil: linalool (52.8 %), 1.8-cineole (8.7 %); Cinnamon Basil: methyl chavicol (60.4 %), 1.8-cine-ole (6.3 %), linalool (3.3 %) and cadinol (3.2 %); Italian large leaf Basil …


“Agrionemys Kazachstanica Terbishi” Or The Two-Faced Mongolian Steppe Tortoise, Hermann Ansorge, Uwe Fritz, Khayankhyarvaa Terbish, Setev Shar Jan 2012

“Agrionemys Kazachstanica Terbishi” Or The Two-Faced Mongolian Steppe Tortoise, Hermann Ansorge, Uwe Fritz, Khayankhyarvaa Terbish, Setev Shar

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Although no extant native turtle and tortoise species is known to occur in Mongolia, a new subspecies of the Central Asian tortoise was described by Chkhikvadze under the name Agrionemys kazachstanica terbishi in 2009. The description was based on a mummified tortoise kept in a museum collection. Since then the Mongolian steppe tortoise has been considered as an endemic taxon Testudo horsfieldii terbishi (Chkhikvadze, 2009) for Mongolia.

However, there is no evidence for the occurrence of any wild tortoise species in Mongolia, even in the putative area of origin of the type specimen. The closest confirmed occurrence of Central Asian …


Diploid Allium Ramosum From East Mongolia: A Missing Link For The Origin Of The Crop Species A. Tuberosum?, Batlai Oyuntsetseg, Frank R. Blattner, Nikolai Friesen Jan 2012

Diploid Allium Ramosum From East Mongolia: A Missing Link For The Origin Of The Crop Species A. Tuberosum?, Batlai Oyuntsetseg, Frank R. Blattner, Nikolai Friesen

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In eastern Mongolia, a diploid close relative of the tetraploid (4x) crop species Allium tuberosum and its closest wild relative A. ramosum (4x) was found and characterized by karyotype analysis and with molecular marker techniques. An earlier analyses revealed A. ramosum to be sister of the crop but excluded it as its progenitor. At that time a putative diploid cytotype of A. ramosum was hypothesized as a potential progenitor taxon of the tetraploids. New phylogenetic analyses of chloroplast and nuclear DNA sequences including the recently found cytotype (A. aff. tuberosum) together with A. tuberosum and A. ramosum accessions …


Herpetological Diversity Of Mongolia And Its Conservation Issues, Khorloo Munkhbayar, M, Munkhbaatar Jan 2012

Herpetological Diversity Of Mongolia And Its Conservation Issues, Khorloo Munkhbayar, M, Munkhbaatar

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

From the viewpoint of evolution, the classes of amphibians and reptiles could be considered as relicts, and because they are poikilothermic animals, it’s very difficult for these species to live under the dry and cold climatic conditions in Mongolia. Even species diversity is poor, Mongolian herpetological composition is unique, highly adopted to the country’s harsh climate and originated a long time ago.

In Mongolia, six species of amphibians belong to four genera, four families and two orders and the recorded 21 species of reptiles belong to 13 genera in six families of two suborders.


Uniformity In A Diversity Of Landscapes – Branchiopod Communities In Eastern And Central Mongolia, Ansgar Poloczek, Michael Mühlenberg, Ingo W. Stürmer Jan 2012

Uniformity In A Diversity Of Landscapes – Branchiopod Communities In Eastern And Central Mongolia, Ansgar Poloczek, Michael Mühlenberg, Ingo W. Stürmer

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

While investigating the branchiopod fauna of Mongolia, the uniformity of these crustacean communities through a multitude of different ecological conditions is conspicuous.

We sampled branchiopods in 24 sites through Central- and East-Mongolia, as living animals as well as cysts in soil samples. These sites represent the main types of Mongolia’s vegetation- and ecological-zones: Taiga forests in the western and eastern edge of the Khentey-Mountain ridge, the central and eastern steppe regions, and the Gobi-desert in the south.

In this large amount of differing ecological conditions with a changing human impact, compared to the width of the covered area, we found …


New Data On The Fish Coregonus Peled (Gmelin, 1788) In Some Water Bodies Of Mongolia, Ayuriin Dulmaa Jan 2012

New Data On The Fish Coregonus Peled (Gmelin, 1788) In Some Water Bodies Of Mongolia, Ayuriin Dulmaa

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In connection with the planned establishment of a coregonid fishery and the construction of a specialized hatchery in the area of Western Mongolia a study was undertaken with the aim of studying some parts of the reproductive biology of population of Coregonus peled inhabiting the lake Ulaagchnii Khar (Zavhan aimag). This species was introduced into this Mongolian lake, originally lacking any fish stock, in the period from 1980–1982. 11,230 fish were collected and examined during the periods from 1993–1999 and 2005–2011 and consisted partly of the fish originating from imported and introduced larvae and partly of the individuals belonging about …


Diversity And Distribution Of Mongolian Fish: Recent State, Trends And Studies, Yuri Dgebuadze, Bud Mendsaikhan, Ayurin Dulmaa Jan 2012

Diversity And Distribution Of Mongolian Fish: Recent State, Trends And Studies, Yuri Dgebuadze, Bud Mendsaikhan, Ayurin Dulmaa

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The studies in recent years (2000-2011) have allowed to make more precise the list and ranges of Mongolian fish. This is connected with new findings as well as the continuing process of invasion of alien species. Climate change and increase of human impact transformed ranges and local distribution of fish during last 30 years. Bias on ratio of ecological guilds, number of pathological findings are increasing, and declining of local diversity, rate of growth and fecundity of many species of fish are observed. In the course of long-term observation was confirmed periodically drying of waters of the Central Asian Lake …


Indicators Of Pasture Digression In Steppe Ecosystems Of Mongolia, Elena V. Danzhalova, S. N. Bazha, P. D. Gunin, Yu. I. Drobyshev, T. I. Kazantseva, A. V. Prischepa, N. N. Slemnev, E. Ariunbold Jan 2012

Indicators Of Pasture Digression In Steppe Ecosystems Of Mongolia, Elena V. Danzhalova, S. N. Bazha, P. D. Gunin, Yu. I. Drobyshev, T. I. Kazantseva, A. V. Prischepa, N. N. Slemnev, E. Ariunbold

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The research shows that widely used key measures of vegetation structure (species diversity, projected cover and above-ground phytomass) are not always suitable as indicators of pasture degradation. Based on an analysis above-ground phytomass composition, new quantitative indices are offered that give a more realistic picture of rangeland condition in Mongolia.


Some Taxonomic Records Of Aquatic Insects In The Eroo River Basin (West Khentii, Northern Mongolia), Purevdorj Surenkhorloo, Ravchig Samiya, Jolanta Slowik, Michael Mühlenberg Jan 2012

Some Taxonomic Records Of Aquatic Insects In The Eroo River Basin (West Khentii, Northern Mongolia), Purevdorj Surenkhorloo, Ravchig Samiya, Jolanta Slowik, Michael Mühlenberg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In the Eroo basin of Mongolia, many species of aquatic insects have been recorded including five species of Diptera in the families Psychodidae, Dixidae, and Blephaceridae and 25 species across eight families of stoneflies. One species of Psychodidae, Bazarella baikalensis Wagner is reported for the first time in Mongolia while the other families are discussed and a species list is provided for the country.


Structure And Productivity Of Haloxylon Ammodendron Communities In The Mongolian Gobi, Tamara I. Kazantseva, Nikolay N. Slemnev, Pjotr D. Gunin, Sh. Tsooj Jan 2012

Structure And Productivity Of Haloxylon Ammodendron Communities In The Mongolian Gobi, Tamara I. Kazantseva, Nikolay N. Slemnev, Pjotr D. Gunin, Sh. Tsooj

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Communities of Haloxylon ammodendron are widespread in the Mongolian Gobi where they play a significant role in biodiversity preservation. They occupy several main types of habitats, showing differences in density, projective cover, and productivity. Haloxylon ammodendron plays a similar, if not even more important role in the arid zone of Mongolia as the principal forest-making trees in the Northern part of the country. The complex set of quantitative parameters of Haloxylon ammodendron stands studied here in respect to temporal dynamics can serve as an indicator of both the vitality of desert ecosystems, and of environmental change.


Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara Jan 2012

Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara

Open Access Theses & Dissertations

Almost half the global soil organic carbon pool is found in northern high latitudes. The majority of this soil carbon is stored in a greenhouse inert state within permafrost. As pronounced warming of high northern latitudes ensues, there is a strong likelihood that this substantial soil organic carbon pool will be mobilized to the atmosphere where it is likely to positively enhance greenhouse warming. Modeling studies suggest this positive feedback could alter future climate states of the Arctic and the globe, and affect how humans may need to adapt to climate change. Accordingly, understanding the patterns and controls and the …


Assessment Of Diver Impact During The Spiny Lobster Sport Season, Florida Keys, Usa, Mark Lewis Hartman Jan 2012

Assessment Of Diver Impact During The Spiny Lobster Sport Season, Florida Keys, Usa, Mark Lewis Hartman

USF Tampa Graduate Theses and Dissertations

The Spiny Lobster (Panulirus argus) fishery in Florida is closed during the spawning season (March-July) except for a two-day recreational `miniseason' for sport divers in July, several days prior to the opening of the commercial fishing season. In Monroe County, recreational fishers, who possess a valid Saltwater Fishing License with crawfish stamp, are allowed to harvest six lobsters per day, each with a minimum carapace length of 76.2 mm (3.0 inches). During these two days, approximately 50,000 people attempt to catch lobster, and the number of boats visiting the reef has been estimated to be up to 900 times higher …


Greenhouse Gas Fluxes In Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt Jan 2012

Greenhouse Gas Fluxes In Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt

Environmental Science and Management Faculty Publications and Presentations

Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental trade-offs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet flooding of soils can also increase production of the greenhouse gases nitrous oxide and methane, representing a potential environmental trade-off. Our study aimed to quantify and compare greenhouse gas emissions from unmanaged and restored forested wetlands, as well as actively managed agricultural fields within the North Carolina coastal plain, USA. In sampling …


Recent Changes In The Growth And Nutrient Limitation Of Benthic And Pelagic Algae In Arctic Tundra Ponds, Christina Hernandez Jan 2012

Recent Changes In The Growth And Nutrient Limitation Of Benthic And Pelagic Algae In Arctic Tundra Ponds, Christina Hernandez

Open Access Theses & Dissertations

Arctic ponds are a dominant feature in Barrow, Alaska. Ponds may function as carbon sinks during the growing season from production of photosynthetic organisms like algae; however, little work has been done on this topic. Environmental changes have been occurring in the Arctic stemming from climate change and human perturbations. The focus of this study was to assess a historically studied region for changes in algal primary production that may have been produced due to increases in temperature over the past 40 years and increased human development. Additionally, this study aimed to determine nutrient limitation of algal production in the …


An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla Jan 2012

An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla

Open Access Theses & Dissertations

Land cover change is a significant contributor to environmental change on a global scale. In the arid regions of the southwest US, shrub encroachment is one of the most important forms of land cover change. Many factors contribute to shrub encroachment, which can impact structure and function. In the Chihuahuan Desert, mountain ecosystems are known as biodiversity hotspots and are especially susceptible to environmental change making them useful indicators of global change. The overarching goal of this dissertation is to improve i) understanding of land cover change in a Chihuahuan Desert mountain landscape, and ii) how knowledge of land cover …


Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen Jan 2012

Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen

OES Faculty Publications

Picocyanobacteria represented by Prochlorococcus and Synechococcus have an important role in oceanic carbon fixation and nutrient cycling. In this study, we compared the community composition of picocyanobacteria from diverse marine ecosystems ranging from estuary to open oceans, tropical to polar oceans and surface to deep water, based on the sequences of 16S-23S rRNA internal transcribed spacer (ITS). A total of 1339 ITS sequences recovered from 20 samples unveiled diverse and several previously unknown clades of Prochlorococcus and Synechococcus. Six high-light (HL)-adapted Prochlorococcus clades were identified, among which clade HLVI had not been described previously. Prochlorococcus clades HLIII, HLIV and …