Diversity

1296 KiB

Open AccessArticle

Phyllopshere Bacterial Community Structure of Spinach (Spinacia oleracea) as Affected by Cultivar and Environmental Conditions at Time of Harvest

by Gabriela Lopez-Velasco, Gregory E. Welbaum, Joseph O. Falkinham III and Monica A. Ponder

Diversity 2011, 3(4), 721-738; https://doi.org/10.3390/d3040721 - 20 Dec 2011

Cited by 19 | Viewed by 7883

Abstract

Modern molecular ecology techniques were used to demonstrate the effects of plant genotype and environmental conditions prior to harvest on the spinach epiphytic bacterial community. Three cultivars of spinach with different leaf topographies were collected at three different periods during the fall growing [...] Read more.

Modern molecular ecology techniques were used to demonstrate the effects of plant genotype and environmental conditions prior to harvest on the spinach epiphytic bacterial community. Three cultivars of spinach with different leaf topographies were collected at three different periods during the fall growing season. Leaf surface topography had an effect on diversity and number of culturable bacteria on the phylloepiphtyic community of spinach. Savoy cultivars, which had larger surface area and more stomata and glandular trichomes, where bacterial aggregates were observed, featured more diverse communities with increased richness and larger bacterial populations compared to flat-leaved cultivars. Bacterial community richness was compared using denaturant gradient gel electrophoresis (DGGE), while abundance was quantified using 16s rRNA primers for major phyla. The most diverse communities, both in richness and abundance, were observed during the first sampling period, immediately following a period of rapid spinach growth. Exposure to lower air and soil temperatures and decreased precipitation resulted in significantly reduced bacterial population size and bacterial community richness in November and December. This study describes the effect of the plant characteristics and environmental conditions that affect spinach microbiota population size and diversity, which might have implications in the survival of food and plant bacterial pathogens. Full article

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169 KiB

Open AccessArticle

Ecological Impact on Nitrogen and Phosphorus Cycling of a Widespread Fast-growing Leguminous Tropical Forest Plantation Tree Species, Acacia mangium

by Masahiro Inagaki and Shigehiro Ishizuka

Diversity 2011, 3(4), 712-720; https://doi.org/10.3390/d3040712 - 28 Nov 2011

Cited by 8 | Viewed by 6935

Abstract

Symbiotic nitrogen fixation is one of the major pathways of N input to forest ecosystems, enriching N availability, particularly in lowland tropics. Recently there is growing concern regarding the wide areas of fast-growing leguminous plantations that could alter global N₂O emissions. [...] Read more.

Symbiotic nitrogen fixation is one of the major pathways of N input to forest ecosystems, enriching N availability, particularly in lowland tropics. Recently there is growing concern regarding the wide areas of fast-growing leguminous plantations that could alter global N₂O emissions. Here, we highlight substantially different N and phosphorus utilization and cycling at a plantation of Acacia mangium, which is N₂-fixing and one of the major plantation species in tropical/subtropical Asia. The litterfall, fresh leaf quality and fine-root ingrowth of A. mangium were compared to those of non-N₂-fixing Swietenia macrophylla and coniferous Araucaria cunninghamii in wet tropical climates in Borneo, Malaysia. The N and P concentrations of the A. mangium fresh leaves were higher than those of the other two species, whereas the P concentration in the leaf-litterfall of A. mangium was less than half that of the others; in contrast the N concentration was higher. The N:P ratio in the A. mangium leaf was markedly increased from fresh-leaf (29) to leaf-litterfall (81). Although the N flux in the total litterfall at the A. mangium plantation was large, the fine-root ingrowth of A. mangium significantly increased by applying both N and P. In conclusion, large quantities of N were accumulated and returned to the forest floor in A. mangium plantation, while its P resorption capacity was efficient. Such large N cycling and restricted P cycling in wide areas of monoculture A. mangium plantations may alter N and P cycling and their balance in the organic layer and soil on a stand level. Full article

(This article belongs to the Special Issue Biodiversity and Forest Dynamics and Functions)

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1236 KiB

Open AccessArticle

Illustration of the Structure of Arthropod Assemblages (Collembola and Lepidoptera) in Different Forest Types: An Example in the French Pyrenees

by Carine Luque, Luc Legal, Peter Winterton, Nestor A. Mariano and Charles Gers

Diversity 2011, 3(4), 693-711; https://doi.org/10.3390/d3040693 - 18 Nov 2011

Cited by 7 | Viewed by 7202

Abstract

To analyze the impact of management choices on diversity in Pyrenean forests, we selected two ecological indicators: springtails; indicators of long-term responses to perturbation, and moths; which respond quickly to changes in their environment. Our data show that monoculture has a short-term impact [...] Read more.

To analyze the impact of management choices on diversity in Pyrenean forests, we selected two ecological indicators: springtails; indicators of long-term responses to perturbation, and moths; which respond quickly to changes in their environment. Our data show that monoculture has a short-term impact on overall diversity and richness of species but with a relative resilience capacity of the forest ecosystem. More precisely, real impacts are visible on dynamics and abundances of certain species, depending on the vertical distribution of the biota and on the composition of soil and forest floor. Full article

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12777 KiB

Open AccessReview

On the Breeds of Cattle—Historic and Current Classifications

by Marleen Felius, Peter A. Koolmees, Bert Theunissen, European Cattle Genetic Diversity Consortium and Johannes A. Lenstra

Diversity 2011, 3(4), 660-692; https://doi.org/10.3390/d3040660 - 9 Nov 2011

Cited by 73 | Viewed by 32887

Abstract

Classification of cattle breeds contributes to our understanding of the history of cattle and is essential for an effective conservation of genetic diversity. Here we review the various classifications over the last two centuries and compare the most recent classifications with genetic data. [...] Read more.

Classification of cattle breeds contributes to our understanding of the history of cattle and is essential for an effective conservation of genetic diversity. Here we review the various classifications over the last two centuries and compare the most recent classifications with genetic data. The classifications devised during the 19th to the late 20th century were in line with the Linnaean taxonomy and emphasized cranial or horn morphology. Subsequent classifications were based on coat color, geographic origin or molecular markers. Several theories were developed that linked breed characteristics either to a supposed ancestral aurochs subspecies or to a presumed ethnic origin. Most of the older classifications have now been discarded, but have introduced several Latin terms that are still in use. The most consistent classification was proposed in 1995 by Felius and emphasizes the geographic origin of breeds. This is largely in agreement with the breed clusters indicated by a biochemical and molecular genetic analysis, which reflect either groups of breeds with a common geographic origin or single breeds that have expanded by export and/or crossbreeding. We propose that this information is also relevant for managing the genetic diversity of cattle. Full article

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15223 KiB

Open AccessArticle

Genetic Diversity in Jatropha curcas Populations in the State of Chiapas, Mexico

by Isidro Ovando-Medina, Adriana Sánchez-Gutiérrez, Lourdes Adriano-Anaya, Francisco Espinosa-García, Juan Núñez-Farfán and Miguel Salvador-Figueroa

Diversity 2011, 3(4), 641-659; https://doi.org/10.3390/d3040641 - 28 Oct 2011

Cited by 36 | Viewed by 10124

Abstract

Jatropha curcas L. has become an important source of oil production for biodiesel fuel. Most genetic studies of this plant have been conducted with Asian and African accessions, where low diversity was encountered. There are no studies of this kind focusing in the [...] Read more.

Jatropha curcas L. has become an important source of oil production for biodiesel fuel. Most genetic studies of this plant have been conducted with Asian and African accessions, where low diversity was encountered. There are no studies of this kind focusing in the postulated region of origin. Therefore, five populations of J. curcas were studied in the state of Chiapas, Mexico, using amplified fragment length polymorphism (AFLP) markers. One hundred and fifty-two useful markers were obtained: overall polymorphism = 81.18% and overall Nei’s genetic diversity (He) = 0.192. The most diverse population was the Border population [He: 0.245, Shanon’s information index (I): 0.378]. A cluster analysis revealed the highest dissimilarity coefficient (0.893) yet to be reported among accessions. An analysis of molecular variance (AMOVA) revealed that the greatest variation is within populations (87.8%), followed by the variation among populations (7.88%). The PhiST value (0.121) indicated moderate differentiation between populations. However, a spatial AMOVA (SAMOVA) detected a stronger genetic structure of populations, with a PhiST value of 0.176. To understand the fine structure of populations, an analysis of data with Bayesian statistics was conducted with software Structure^©. The number of genetic populations (K) was five, with mixed ancestry in most individuals (genetic migrants), except in the Soconusco, where there was a tiny fraction of fragments from other populations. In contrast, SAMOVA grouped populations in four units. To corroborate the above findings, we searched for possible genetic barriers, determining as the main barrier that separating the Border from the rest of the populations. The results are discussed based on the possible ancestry of populations. Full article

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765 KiB

Open AccessArticle

Resilience of Florida Keys Coral Communities Following Large-Scale Disturbances

by Deborah L. Santavy, Erich M. Mueller, Lauri MacLaughlin, Esther C. Peters, Robert L. Quarles and Mace G. Barron

Diversity 2011, 3(4), 628-640; https://doi.org/10.3390/d3040628 - 3 Oct 2011

Cited by 3 | Viewed by 8397

Abstract

The decline of coral reefs in the Caribbean over the last 40 years has been attributed to multiple chronic stressors and episodic large-scale disturbances. This study assessed the resilience of coral communities in two different regions of the Florida Keys reef system between [...] Read more.

The decline of coral reefs in the Caribbean over the last 40 years has been attributed to multiple chronic stressors and episodic large-scale disturbances. This study assessed the resilience of coral communities in two different regions of the Florida Keys reef system between 1998 and 2002 following hurricane impacts and coral bleaching in 1998. Resilience was assessed from changes in coral abundance, diversity, disease, and bleaching prevalence in reefs near the remote off-shore islands of the Dry Tortugas compared to reefs near Key West, a center of high population density and anthropogenic influences. During the first assessment in spring 1998, Key West and Dry Tortugas coral communities had similar abundance, species diversity, and disease prevalence. Bleaching and disease significantly increased in all reef areas during the summer 1998 El Niño event, with Key West reefs exhibiting higher bleaching and disease prevalence and severity compared to Dry Tortugas. Acroporids and total coral abundance significantly declined in both regions during 1998 following mass-coral bleaching and hurricane impact, but remained reduced only on Key West reefs during the 5-year assessment. These results provide additional evidence that coral reef systems distant from anthropogenic influences may have greater resilience to large-scale disturbances. Full article

(This article belongs to the Special Issue Coral Reef Diversity: Climate Change and Coral Reef Degradation)

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967 KiB

Open AccessArticle

Living More Than Just Enough for the City: Persistence of High-Quality Vegetation in Natural Areas in an Urban Setting

by Rebecca W. Dolan, Jessica D. Stephens and Marcia E. Moore

Diversity 2011, 3(4), 611-627; https://doi.org/10.3390/d3040611 - 3 Oct 2011

Cited by 6 | Viewed by 7565

Abstract

Urban environments pose special challenges to flora, including altered disturbance regimes, habitat fragmentation, and increased opportunity for invasion by non-native species. In addition, urban natural area represents most people’s contact with nature, given the majority of the world’s population currently live in cities. [...] Read more.

Urban environments pose special challenges to flora, including altered disturbance regimes, habitat fragmentation, and increased opportunity for invasion by non-native species. In addition, urban natural area represents most people’s contact with nature, given the majority of the world’s population currently live in cities. We used coefficients of conservatism (C-values), a system that ranks species based on perceived fidelity to remnant native plant communities that retain ecological integrity, to quantify habitat quality of 14 sites covering 850 ha within the city of Indianapolis, Indiana, in the Midwestern United States. All sites contained significant natural area and were inventoried via intensive complete censuses throughout one or two growing seasons within the last 15 years. Mean C-values for five sites were high, especially when compared to values reported for the highest quality preserves in central Indiana. However, for most sites the difference in mean C-value with and without non-natives was rather high, meaning that natural quality is likely to have been compromised by the presence of non-natives. Sites receiving the highest levels of stewardship and those with the least public access via trails had the highest mean native C-values. A total of 34 invasive non-native species were found across all 14 sites. Most were woody species. Mean C-value over all sites was significantly negatively correlated with the number of non-natives present, especially those considered invasive. These results demonstrate for the Indianapolis area, and likely other urbanized Midwestern cities, remnant natural areas can retain high ecological value, especially if they receive regular environmental stewardship. Full article

(This article belongs to the Special Issue Urban Biodiversity Conservation and Restoration)

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1886 KiB

Open AccessArticle

Monitoring Coral Health to Determine Coral Bleaching Response at High Latitude Eastern Australian Reefs: An Applied Model for A Changing Climate

by Steven J. Dalton and Andrew G. Carroll

Diversity 2011, 3(4), 592-610; https://doi.org/10.3390/d3040592 - 30 Sep 2011

Cited by 22 | Viewed by 9208

Abstract

Limited information is available on the bleaching susceptibility of coral species that dominate high latitude reefs along the eastern seaboard of Australia. The main aims of this study were to: (i) monitor coral health and spatial patterns of coral bleaching response at the [...] Read more.

Limited information is available on the bleaching susceptibility of coral species that dominate high latitude reefs along the eastern seaboard of Australia. The main aims of this study were to: (i) monitor coral health and spatial patterns of coral bleaching response at the Solitary Islands Marine Park (SIMP) and Lord Howe Island Marine Park (LHIMP), to determine variability of bleaching susceptibility among coral taxa; (ii) predict coral bleaching thresholds at 30 °S and 31.5 °S, extrapolated from published bleaching threshold data; and (iii) propose a subtropical northern New South Wales coral bleaching model from biological and physical data. Between 2005 and 2007 minor bleaching was observed in dominant coral families including Pocilloporidae, Poritidae and Dendrophylliidae in the SIMP and Pocilloporidae, Poritidae and Acroporidae (Isopora and Montipora spp.) in the LHIMP, with a clear difference in bleaching susceptibility found between sites, both within and between locations. Bleaching susceptibility was highest in Porites spp. at the most offshore island site within the SIMP during summer 2005. Patterns of subtropical family bleaching susceptibility within the SIMP and LHIMP differed to those previously reported for the central Great Barrier Reef (GBR). These differences may be due to a number of factors, including temperature history and/or the coral hosts association with different zooxanthellae clades, which may have lower thermal tolerances. An analysis of published estimates of coral bleaching thresholds from the Caribbean, South Africa, GBR and central and northern Pacific regions suggests that the bleaching threshold at 30–31.5 °S ranges between 26.5–26.8 °C. This predicted threshold was confirmed by an extensive coral bleaching event on the world’s southernmost coral reef at Lord Howe Island, during the 2010 austral summer season. These results imply that dominant coral taxa at subtropical reefs along the eastern Australian seaboard are highly susceptible to thermal stress; which, in turn, could lead to a future decline in total live coral cover if predicted rising seawater temperatures lead to more frequent coral bleaching events in future. Full article

(This article belongs to the Special Issue Coral Reef Diversity: Climate Change and Coral Reef Degradation)

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6263 KiB

Open AccessArticle

Using DNA Barcoding and Standardized Sampling to Compare Geographic and Habitat Differentiation of Crustaceans: A Hawaiian Islands Example

by Laetitia Plaisance, Russell Brainard, M. Julian Caley and Nancy Knowlton

Diversity 2011, 3(4), 581-591; https://doi.org/10.3390/d3040581 - 29 Sep 2011

Cited by 18 | Viewed by 9380

Abstract

Recently, the Census of Marine Life has explored methods to assess coral reef diversity by combining standardized sampling (to permit comparison across sites) with molecular techniques (to make rapid counts of species possible). To date, this approach has been applied across geographically broad [...] Read more.

Recently, the Census of Marine Life has explored methods to assess coral reef diversity by combining standardized sampling (to permit comparison across sites) with molecular techniques (to make rapid counts of species possible). To date, this approach has been applied across geographically broad scales (seven sites spanning the Indian, Pacific and Atlantic Oceans), focusing on similar habitats at all sites (10–12 m forereef). Here we examine crustacean spatial diversity patterns for a single atoll, comparing results for four sites (comprising forereef, backreef, and lagoon habitats) at French Frigate Shoals (FFS), Northwestern Hawaiian Islands, Hawaii, USA, within the Papahanaumokuakea Marine National Monument. The Bray-Curtis index of similarity across these habitats at FFS was the same or greater than the similarity between similar habitats on Heron Island and Lizard Island in the Great Barrier Reef and much greater than similarity between more widely separated localities in the Indo-Pacific Ocean (e.g., Ningaloo, Moorea, French Polynesia or the Line Islands). These results imply that, at least for shallow reefs, sampling multiple locations versus sampling multiple habitats within a site maximizes the rate at which we can converge on the best global estimate of coral reef biodiversity. Full article

(This article belongs to the Special Issue Coral Reef Diversity: Climate Change and Coral Reef Degradation)

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299 KiB

Open AccessArticle

Diversity of Pharmacological Properties in Chinese and European Medicinal Plants: Cytotoxicity, Antiviral and Antitrypanosomal Screening of 82 Herbal Drugs

by Florian Herrmann, Marta R. Romero, Alba G. Blazquez, Dorothea Kaufmann, Mohamed L. Ashour, Stefan Kahl, Jose J.G. Marin, Thomas Efferth and Michael Wink

Diversity 2011, 3(4), 547-580; https://doi.org/10.3390/d3040547 - 26 Sep 2011

Cited by 40 | Viewed by 11715

Abstract

In an extensive screening, the antiviral, antitrypanosomal and anticancer properties of extracts from 82 plants used in traditional Chinese medicine and European phytomedicine were determined. Several promising plants that were highly effective against hepatitis B virus (HBV), bovine viral diarrhoea virus (BVDV)—a flavivirus [...] Read more.

In an extensive screening, the antiviral, antitrypanosomal and anticancer properties of extracts from 82 plants used in traditional Chinese medicine and European phytomedicine were determined. Several promising plants that were highly effective against hepatitis B virus (HBV), bovine viral diarrhoea virus (BVDV)—a flavivirus used here as a surrogate in vitro model of hepatitis C virus, trypanosomes (Trypanosoma brucei brucei) and several cancer cell lines were identified. Six aqueous extracts from Celosia cristata, Ophioglossum vulgatum, Houttuynia cordata, Selaginella tamariscina, Alpinia galanga and Alpinia oxyphylla showed significant antiviral effects against BVDV without toxic effects on host embryonic bovine trachea (EBTr) cells, while Evodia lepta, Hedyotis diffusa and Glycyrrhiza spp. demonstrated promising activities against the HBV without toxic effects on host human hepatoblastoma cells transfected with HBV-DNA (HepG2 2.2.15) cells. Seven organic extracts from Alpinia oxyphylla, Coptis chinensis, Kadsura longipedunculata, Arctium lappa, Panax ginseng, Panax notoginseng and Saposhnikovia divaricata inhibited T. b. brucei. Moreover, among fifteen water extracts that combined high antiproliferative activity (IC₅₀ 0.5–20 µg/mL) and low acute in vitro toxicity (0–10% reduction in cell viability at IC₅₀), Coptis chinensis presented the best beneficial characteristics. In conclusion, traditional herbal medicine from Europe and China still has a potential for new therapeutic targets and therapeutic applications. Full article

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Diversity, Volume 3, Issue 4 (December 2011) – 10 articles , Pages 547-738

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