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Sample records for litter frogs amphibia

  1. Complete mitochondrial genome of the Seoul frog Rana chosenica (Amphibia, Ranidae): comparison of R. chosenica and R. plancyi.

    PubMed

    Ryu, Shi Hyun; Hwang, Ui Wook

    2011-06-01

    Here, we have sequenced the complete mitochondrial genome of the Seoul frog Rana chosenica (Amphibia, Ranidae), which is known as a Korean endemic species. It is listed as a vulnerable species by IUCN Red List and also an endangered species in South Korea. The complete mitochondrial genome of R. chosenica consists of 18,357 bp. Its gene arrangement pattern was identical with those of other Rana frogs. We compared the mitochondrial genome of R. chosenica with that of the Peking frog Rana plancyi that has been known closely related to R. chosenica. Nucleotide sequence similarity between the two whole mitochondrial genomes was 95.7%, and the relatively low similarity seems to indicate that the two species are distinctly separated on the species level. The information of mitochondrial genome comparison of the two species was discussed in detail.

  2. Ornithodoros faccinii n. sp. (Acari: Ixodida: Argasidae) parasitizing the frog Thoropa miliaris (Amphibia: Anura: Cycloramphidae) in Brazil.

    PubMed

    Barros-Battesti, Darci Moraes; Landulfo, Gabriel Alves; Luz, Hermes Ribeiro; Marcili, Arlei; Onofrio, Valeria Castilho; Famadas, Kátia Maria

    2015-05-13

    Most argasid ticks from the Neotropical region are parasites of mammals and birds, with a few records from reptiles. Many species of the genus Ornithodoros are known only through larval descriptions, and their chaetotaxy and morphological characteristics have been used to separate the taxa. In the present study, we describe the larva and the nymph of first instar of a new species of the genus Ornithodoros that was collected from frogs of the species Thoropa miliaris. Larvae of Ornithodoros were collected from frogs of the species T. miliaris at waterfalls in the state of Rio de Janeiro, southeastern Brazil. The larval and nymphal description was based on optical and scanning electron microscopy. Molecular analysis using the argasid 16S rRNA sequences available in GenBank was also conducted. Ornithodoros faccinii sp. n. is closely related to Ornithodoros clarki Jones & Clifford, Ornithodoros marinkellei Kohls, Clifford & Jones, Ornithodoros capensis Neumann and Ornithodoros sawaii Kitaoka & Susuki. However, the larval morphology of the new species is unique. The mitochondrial 16S rDNA partial sequence of O. faccinii generated in the present study was deposited in GenBank under the number KP861242. The larvae collected from Thoropa miliaris are a new species, Ornithodoros faccinii n. sp. This is the first report of argasid ticks on frogs in Brazil, the second on frogs and the third on Amphibia in the Neotropical region.

  3. Climatic oscillations triggered post-Messinian speciation of Western Palearctic brown frogs (Amphibia, Ranidae).

    PubMed

    Veith, M; Kosuch, J; Vences, M

    2003-02-01

    Oscillating glacial cycles over the past 2.4 million years are proposed to have had a major impact on the diversity of contemporary species communities. We used mitochondrial and nuclear DNA sequence data to infer phylogenetic relationships within Western Palearctic brown frogs and to test the influence of Pliocene and Pleistocene climatic changes on their evolution. We sequenced 1976bp of the mitochondrial genes 16S rRNA and cytochrome b and of the nuclear rhodopsin gene for all current species and subspecies. Based on an established allozyme clock for Western Palearctic water frogs and substitution rate constancy among water frogs and brown frogs, we calibrated a molecular clock for 1425bp of the 16S and rhodopsin genes. We applied this clock to date speciation events among brown frogs. Western Palearctic brown frogs underwent a basal post-Messinian radiation about 4 million years ago (mya) into five major clades: three monotypic lineages (Rana dalmatina, Rana latastei, Rana graeca), an Anatolian lineage, and a lineage comprising Rana italica, Rana arvalis, and all Iberian taxa. Polytypic lineages radiated further in concordance with the onset of climatic oscillations ca. 3.2, 2.0, and 1.0-0.6 mya, respectively. The dated fossil record corroborates our paleobiogeographic scenario. We conclude that drastic climatic changes followed by successive temperature oscillations "trapped" most brown frog species in their southern European glacial refugia with enough time to speciate. Substantial dispersal was only possible during extensive interglacial periods of a constant subtropical climate.

  4. New Material of Beelzebufo, a Hyperossified Frog (Amphibia: Anura) from the Late Cretaceous of Madagascar

    PubMed Central

    Evans, Susan E.; Groenke, Joseph R.; Jones, Marc E. H.; Turner, Alan H.; Krause, David W.

    2014-01-01

    The extant anuran fauna of Madagascar is exceptionally rich and almost completely endemic. In recent years, many new species have been described and understanding of the history and relationships of this fauna has been greatly advanced by molecular studies, but very little is known of the fossil history of frogs on the island. Beelzebufo ampinga, the first named pre-Holocene frog from Madagascar, was described in 2008 on the basis of numerous disarticulated cranial and postcranial elements from the Upper Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. These specimens documented the presence of a hyperossified taxon that differed strikingly from extant Malagasy frogs in its large size and heavy coarse cranial exostosis. Here we describe and analyse new, articulated, and more complete material of the skull, vertebral column, and hind limb, as well as additional isolated elements discovered since 2008. μCT scans allow a detailed understanding of both internal and external morphology and permit a more accurate reconstruction. The new material shows Beelzebufo to have been even more bizarre than originally interpreted, with large posterolateral skull flanges and sculptured vertebral spine tables. The apparent absence of a tympanic membrane, the strong cranial exostosis, and vertebral morphology suggest it may have burrowed during seasonally arid conditions, which have been interpreted for the Maevarano Formation from independent sedimentological and taphonomic evidence. New phylogenetic analyses, incorporating both morphological and molecular data, continue to place Beelzebufo with hyloid rather than ranoid frogs. Within Hyloidea, Beelzebufo still groups with the South American Ceratophryidae thus continuing to pose difficulties with both biogeographic interpretations and prior molecular divergence dates. PMID:24489877

  5. Oviduct modifications in foam-nesting frogs, with emphasis on the genus Leptodactylus (Amphibia, Leptodactylidae)

    USGS Publications Warehouse

    Furness, Andrew I.; McDiarmid, Roy W.; Heyer, W. Ronald; Zug, George R.

    2010-01-01

    Various species of frogs produce foam nests that hold their eggs during development. We examined the external morphology and histology of structures associated with foam nest production in frogs of the genus Leptodactylus and a few other taxa. We found that the posterior convolutions of the oviducts in all mature female foam-nesting frogs that we examined were enlarged and compressed into globular structures. This organ-like portion of the oviduct has been called a "foam gland" and these structures almost certainly produce the secretion that is beaten by rhythmic limb movements into foam that forms the nest. However, the label "foam gland" is a misnomer because the structures are simply enlarged and tightly folded regions of the pars convoluta of the oviduct, rather than a separate structure; we suggest the name pars convoluta dilata (PCD) for this feature. Although all the foam-nesters we examined had a pars convoluta dilata, its size and shape showed considerable interspecific variation. Some of this variation likely reflects differences in the breeding behaviors among species and in the size, type, and placement of their foam nests. Other variation, particularly in size, may be associated with the physiological periodicity and reproductive state of the female, her age, and/or the number of times she has laid eggs.

  6. Helminth parasites of the leopard frog Lithobates sp. Colima (Amphibia: Ranidae) from Colima, Mexico.

    PubMed

    Cabrera-Guzmán, Elisa; Garrido-Olvera, Lorena; León-Règagnon, Virginia

    2010-08-01

    The helminth fauna inhabiting Lithobates sp. Colima from Ticuizitán, Colima, Mexico, comprises 10 species: 4 digeneans ( Clinostomum sp., Glypthelmins quieta , Haematoloechus sp., and Langeronia macrocirra ), 5 nematodes ( Aplectana itzocanensis , Cosmocerca podicipinus , Foleyellides striatus , Oswaldocruzia subauricularis , and Rhabdias sp.), and 1 cestode (Cyclophyllidea). Glypthelmins quieta , L. macrocirra , and A. itzocanensis represent new host records. These observations, added to previous records from Acapulco, Guerrero, Mexico, indicate that the helminth fauna of Lithobates sp. from Colima comprises 25 taxa. Frogs are being parasitized by 3 infection routes: ingestion of intermediate host, skin penetration by larval forms, and transmission by vectors. Species of Aplectana , Cosmocerca , Foleyellides , and Oswaldocruzia occurred in high prevalence in Colima, similar to a previous study on the same frog species from Guerrero. In Colima, Glypthelmins , Haematoloechus , and Rhabdias also occurred in high prevalence. Haematoloechus species reached the highest mean intensity in both localities. The semiaquatic habits of this species of frog and the availability of particular feeding resources appear to determine the helminth composition and infection levels; however, co-speciation events also play an important role structuring these helminth communities.

  7. Leaf litter resource quality induces morphological changes in wood frog (Lithobates sylvaticus) metamorphs.

    PubMed

    Stoler, Aaron B; Stephens, Jeffrey P; Relyea, Rick A; Berven, Keith A; Tiegs, Scott D

    2015-11-01

    For organisms that exhibit complex life cycles, resource conditions experienced by individuals before metamorphosis can strongly affect phenotypes later in life. Such resource-induced effects are known to arise from variation in resource quantity, yet little is known regarding effects stemming from variation in resource quality (e.g., chemistry). For larval anurans, we hypothesized that variation in resource quality will induce a gradient of effects on metamorph morphology. We conducted an outdoor mesocosm experiment in which we manipulated resource quality by rearing larval wood frogs (Lithobates sylvaticus) under 11 leaf litter treatments. The litter species represented plant species found in open- and closed-canopy wetlands and included many plant species of current conservation concern (e.g., green ash, common reed). Consistent with our hypothesis, we found a gradient of responses for nearly all mass-adjusted morphological dimensions. Hindlimb dimensions and gut mass were positively associated with litter nutrient content and decomposition rate. In contrast, forelimb length and head width were positively associated with concentrations of phenolic acids and dissolved organic carbon. Limb lengths and widths were positively related with the duration of larval period, and we discuss possible hormonal mechanisms underlying this relationship. There were very few, broad differences in morphological traits of metamorphs between open- and closed-canopy litter species or between litter and no-litter treatments. This suggests that the effects of litter on metamorph morphology are litter species-specific, indicating that the effects of changing plant community structure in and around wetlands will largely depend on plant species composition.

  8. Phylogenetic relationships of Oriental torrent frogs in the genus Amolops and its allies (Amphibia, Anura, Ranidae).

    PubMed

    Matsui, Masafumi; Shimada, Tomohiko; Liu, Wan-Zhao; Maryati, Mohamed; Khonsue, Wichase; Orlov, Nikolai

    2006-03-01

    We investigated the phylogenetic relationships among 20 species of Oriental torrent frogs in the genus Amolops and its allies from China and Southeast Asia based on 1346-bp sequences of the mitochondrial 12S and 16S rRNA genes. Oriental species of the tribe Ranini form a monophyletic group containing 11 clades (Rana temporaria + Pseudoamolops, R. chalconota, four clades of Amolops, Meristogenys, three clades of Huia species, and Staurois) for which the phylogenetic relationships are unresolved. The genus Amolops consists of southern Chinese, southwestern Chinese, Thai, and Vietnamese-Malaysian lineages, but their relationships are also unresolved. The separation of southern and southwestern lineages within China conforms to previous morphological and karyological results. Species of Huia do not form a monophyletic group, whereas those of Meristogenys are monophyletic. Because P. sauteri is a sister species of R. temporaria, distinct generic status of Pseudoamolops is unwarranted.

  9. DNA barcoding and the identification of tree frogs (Amphibia: Anura: Rhacophoridae).

    PubMed

    Dang, Ning-Xin; Sun, Feng-Hui; Lv, Yun-Yun; Zhao, Bo-Han; Wang, Ji-Chao; Murphy, Robert W; Wang, Wen-Zhi; Li, Jia-Tang

    2016-07-01

    The DNA barcoding gene COI (cytochrome c oxidase subunit I) effectively identifies many species. Herein, we barcoded 172 individuals from 37 species belonging to nine genera in Rhacophoridae to test if the gene serves equally well to identify species of tree frogs. Phenetic neighbor joining and phylogenetic Bayesian inference were used to construct phylogenetic trees, which resolved all nine genera as monophyletic taxa except for Rhacophorus, two new matrilines for Liuixalus, and Polypedates leucomystax species complex. Intraspecific genetic distances ranged from 0.000 to 0.119 and interspecific genetic distances ranged from 0.015 to 0.334. Within Rhacophorus and Kurixalus, the intra- and interspecific genetic distances did not reveal an obvious barcode gap. Notwithstanding, we found that COI sequences unambiguously identified rhacophorid species and helped to discover likely new cryptic species via the synthesis of genealogical relationships and divergence patterns. Our results supported that COI is an effective DNA barcoding marker for Rhacophoridae.

  10. The phylogenetic position and diversity of the enigmatic mongrel frog Nothophryne Poynton, 1963 (Amphibia, Anura).

    PubMed

    Bittencourt-Silva, Gabriela B; Conradie, Werner; Siu-Ting, Karen; Tolley, Krystal A; Channing, Alan; Cunningham, Michael; Farooq, Harith M; Menegon, Michele; Loader, Simon P

    2016-06-01

    The phylogenetic relationships of the African mongrel frog genus Nothophryne are poorly understood. We provide the first molecular assessment of the phylogenetic position of, and diversity within, this monotypic genus from across its range-the Afromontane regions of Malawi and Mozambique. Our analysis using a two-tiered phylogenetic approach allowed us to place the genus in Pyxicephalidae. Within the family, Nothophryne grouped with Tomopterna, a hypothesis judged significantly better than alternative hypotheses proposed based on morphology. Our analyses of populations across the range of Nothophryne suggest the presence of several cryptic species, at least one species per mountain. Formal recognition of these species is pending but there is a major conservation concern for these narrowly distributed populations in an area impacted by major habitat change. The phylogenetic tree of pyxicephalids is used to examine evolution of life history, ancestral habitat, and biogeography of this group. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Cytonuclear discordance and historical demography of two brown frogs, Rana tagoi and R. sakuraii (Amphibia: Ranidae).

    PubMed

    Eto, Koshiro; Matsui, Masafumi

    2014-10-01

    Prior studies of mitochondrial genomic variation reveal that the Japanese brown frog Rana tagoi comprises a complex of cryptic species lineages, and that R. sakuraii arose from within this complex. Neither species forms a monophyletic group on the mitochondrial haplotype tree, precluding a simple explanation for the evolutionary origins of R. sakuraii. We present a more complete sampling of mitochondrial haplotypic variation (from the ND1 and 16S genes) plus DNA sequence variation for five nuclear loci (from the genes encoding NCX1, NFIA, POMC, SLC8A3, and TYR) to resolve the evolutionary histories of these species. We test hypotheses of population assignment (STRUCTURE) and isolation-with-migration (IM) using the more slowly evolving nuclear markers. These demographic analyses of nuclear genetic variation confirm species-level distinctness and integrity of R. sakuraii despite its apparent polyphyly on the mitochondrial haplotype tree. Divergence-time estimates from both the mitochondrial haplotypes and nuclear genomic markers suggest that R. sakuraii originated approximately one million years ago, and that incomplete sorting of mitochondrial haplotype lineages best explains non-monophyly of R. sakuraii mitochondrial haplotypes. Cytonuclear discordance elsewhere in R. tagoi reveals a case of mitochondrial introgression between two species lineages on Honshu. The earliest phylogenetic divergence within this species group occurred approximately four million years ago, followed by cladogenetic events in the Pliocene and early Pleistocene yielding 10-13 extant species lineages, including R. sakuraii as one of the youngest.

  12. The complete mitochondrial genome sequence of the Dark-spotted frog Pelophylax nigromaculatus (Amphibia, Anura, Ranidae).

    PubMed

    Jiang, Lichun; Zhao, Li; Liu, Yabin; Leng, Zheng; Zhao, Liping; Ruan, Qiping

    2017-03-01

    The dark-spotted frog (Pelophylax nigromaculatus) belongs to Ranidae. This species is known from the Russian Far East, central, northern and north-eastern China, the Democratic People's Republic of Korea, the Republic of Korea, and Japan. In this study, the complete mitochondrial genome of P. nigromaculatus was sequenced. The mitogenome was 17 567 bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a non-coding control region. As in other vertebrates, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes which are encoded on the light strand. The overall base composition of the P. nigromaculatus is 29.2% A, 27.4% T, 28.4% C, and 15.0% G. Phylogenetic analysis showed P. nigromaculatus was closely related to P. plancyi and P. chosenicus. The complete mitogenome of P. nigromaculatus can provide important data for the studies on phylogenetic relationship and population genetics to further explore the taxonomic status of this species.

  13. A new species of tree frog genus Rhacophorus from Sumatra, Indonesia Amphibia, Anura).

    PubMed

    Hamidy, Amir; Kurniati, Hellen

    2015-04-14

    A small-sized tree frog of the genus Rhacophorus is described on the basis of 18 specimens collected from three different localities on Sumatra Island, Indonesia. Rhacophorus indonesiensis sp. nov. is divergent from all other Rhacophorus species genetically and morphologically. The new species is distinguished from its congeners by a combination of: the presence of black spots on the ventral surfaces of the hand and foot webbing, an absence of vomerine teeth, a venter with a white kite-shaped marking, raised white spots on the dorsum or on the head, and a reddish brown dorsum with irregular dark brown blotches and distinct black dots. With the addition of this new species, fifteen species of Rhacophorus are now known from Sumatra, the highest number of species of this genus in the Sundaland region. However, with the increasing conversion of forest to oil palm cultivation or mining, the possibility of the extinction of newly described or as yet undiscovered species is of great concern.

  14. Evidence for an intrinsic factor promoting landscape genetic divergence in Madagascan leaf-litter frogs

    PubMed Central

    Wollenberg Valero, Katharina C.

    2015-01-01

    The endemic Malagasy frog radiations are an ideal model system to study patterns and processes of speciation in amphibians. Large-scale diversity patterns of these frogs, together with other endemic animal radiations, led to the postulation of new and the application of known hypotheses of species diversification causing diversity patterns in this biodiversity hotspot. Both extrinsic and intrinsic factors have been studied in a comparative framework, with extrinsic factors usually being related to the physical environment (landscape, climate, river catchments, mountain chains), and intrinsic factors being clade-specific traits or constraints (reproduction, ecology, morphology, physiology). Despite some general patterns emerging from such large-scale comparative analyses, it became clear that the mechanism of diversification in Madagascar may vary among clades, and may be a multifactorial process. In this contribution, I test for intrinsic factors promoting population-level divergence within a clade of terrestrial, diurnal leaf-litter frogs (genus Gephyromantis) that has previously been shown to diversify according to extrinsic factors. Landscape genetic analyses of the microendemic species Gephyromantis enki and its widely distributed, larger sister species Gephyromantis boulengeri over a rugged landscape in the Ranomafana area shows that genetic variance of the smaller species cannot be explained by landscape resistance alone. Both topographic and riverine barriers are found to be important in generating this divergence. This case study yields additional evidence for the probable importance of body size in lineage diversification. PMID:26136766

  15. Evidence for an intrinsic factor promoting landscape genetic divergence in Madagascan leaf-litter frogs.

    PubMed

    Wollenberg Valero, Katharina C

    2015-01-01

    The endemic Malagasy frog radiations are an ideal model system to study patterns and processes of speciation in amphibians. Large-scale diversity patterns of these frogs, together with other endemic animal radiations, led to the postulation of new and the application of known hypotheses of species diversification causing diversity patterns in this biodiversity hotspot. Both extrinsic and intrinsic factors have been studied in a comparative framework, with extrinsic factors usually being related to the physical environment (landscape, climate, river catchments, mountain chains), and intrinsic factors being clade-specific traits or constraints (reproduction, ecology, morphology, physiology). Despite some general patterns emerging from such large-scale comparative analyses, it became clear that the mechanism of diversification in Madagascar may vary among clades, and may be a multifactorial process. In this contribution, I test for intrinsic factors promoting population-level divergence within a clade of terrestrial, diurnal leaf-litter frogs (genus Gephyromantis) that has previously been shown to diversify according to extrinsic factors. Landscape genetic analyses of the microendemic species Gephyromantis enki and its widely distributed, larger sister species Gephyromantis boulengeri over a rugged landscape in the Ranomafana area shows that genetic variance of the smaller species cannot be explained by landscape resistance alone. Both topographic and riverine barriers are found to be important in generating this divergence. This case study yields additional evidence for the probable importance of body size in lineage diversification.

  16. Effects of forest fragmentation and habitat degradation on West African leaf-litter frogs.

    PubMed

    Hillers, Annika; Veith, Michael; Rödel, Mark-Oliver

    2008-06-01

    Habitat degradation alters the dynamics and composition of anuran assemblages in tropical forests. The effects of forest fragmentation on the composition of anuran assemblages are so far poorly known. We studied the joint influence of forest fragmentation and degradation on leaf-litter frogs. We specifically asked whether the processes structuring leaf-litter anuran assemblages in fragmented forests are the same as those in continuous forests. We analyzed anuran assemblages with respect to habitat characteristics, including fragmentation and degradation parameters. In comparison with continuous forests, species richness and diversity were lower and assemblage composition was altered in forest fragments. These changes seemed to be mainly caused by habitat degradation rather than forest fragmentation. Availability of aquatic sites for breeding, vegetation structure (including those variables indicating degradation), and leaf-litter cover had the most influence on the presence of single species. The comparatively small impact of fragmentation on anurans might be due to the location of the study area; it still possessed large tracts of continuous forest. These forest blocks may stabilize the regional rainforest climate and thus weaken the effects of fragmentation.

  17. [Ploidy and genetic structure of hybrid populations of water frogs Pelophylax esculentus (L., 1758) complex (Amphibia, Ranidae) of Ukraine].

    PubMed

    Mezhzherin, S V; Morozov-Leonov, S Iu; Rostovskaia, O V; Shabanov, D A; Sobolenko, L Iu

    2010-01-01

    The present study of green frog hybrid populations of Ukraine, including analysis of allozyme variability and planimetric analysis oferythrocytes size has confirmed that the unique region in this area is the Severski Donets basin The allopolyploid individuals there are met very frequently (5.7% of all investigated frogs). In other areas of Ukraine only two polyploid hybrids have been recorded. Beside that, one frog was defined as triploid Rana ridibundus. According to our investigations, all triploid hybrids from the Severski Donets basin are identified as P. esculentu (=lessonae)--2 ridibundus males.

  18. Preparation and ultrastructure of spermatozoa from green poison frogs, Dendrobates auratus, following hormonal induced spermiation (Amphibia, Anura, Dendrobatidae).

    PubMed

    Lipke, Christian; Meinecke-Tillmann, Sabine; Meyer, Wilfried; Meinecke, Burkhard

    2009-07-01

    Few ultrastructural studies have been performed on members of the Dendrobatidae, although such investigations can be useful for the understanding of reproductive patterns, as a diagnostic method for males in breeding programs for endangered amphibians and for phylogenetic analysis. The sperm ultrastructure of the Green Poison Frog, Dendrobates auratus, from Panama is described following induced spermiation in living animals. To date only testicular spermatozoa in other dendrobatid frogs have been analysed. Moreover, an electron microscopic preparation method (transmission and scanning electron microscopy) for dendrobatid sperm cells in low concentration is presented. Sperm cells from stimulated frogs (100 IU human chorionic gonadotropin, hCG, twice at an interval of 1h) were recovered via cloaca lavage using 600 microl isotonic phosphate-free amphibian saline (IPS). Centrifuged flushings (5 min, 173 x g) were deposited on microscopic slides. Adherent spermatozoa were treated with Karnovsky fixative (overnight, 4 degrees C). After postfixation (2h, 1% osmium tetroxide), samples were dehydrated in series of ascending acetones (30-100%). For transmission electron microscopy sperm cells were encapsulated using Epon and 1.5% 2,4,6-tris(dimethylaminomethyl)phenol (DMP 30). Ultrathin sections (70 nm) were cut and stained with uranyl acetate (30 min) and lead citrate (5 min). Sperm cells are filiform with a 21.1+/-2.7 microm long and arcuated head and a single tail (35.0+/-4.2 microm length). Their acrosomal complex is located at the anterior portion of the head and consists of the acrosomal vesicle which has low electron density, and the subjacent electron-dense subacrosomal cone. In transverse section, the nucleus is circular (1.9+/-0.2 microm diameter) and conical in longitudinal section. It is surrounded by several groups of mitochondria. The chromatin is highly condensed and electron-dense but shows numerous electron-lucent inclusions. A short midpiece has a

  19. Development and growth of long bones in European water frogs (Amphibia: Anura: Ranidae), with remarks on age determination.

    PubMed

    Rozenblut, Beata; Ogielska, Maria

    2005-09-01

    Differentiation and development of long bones were studied in European water frogs: Rana lessonae, R. ridibunda, and R. esculenta. The study included premetamorphic larvae (Gosner Stage 40) to frogs that were 5 years old. Femora, metatarsal bones, and proximal phalanges of the hindlimb exhibit the same pattern of periosteal bone differentiation and the same pattern of growth. Longitudinal and radial growth of these bones was studied by examination of the diaphyses and epiphyses, particularly where the edge of periosteal bone is inserted into the epiphysis. The periosteum seems to be responsible for both longitudinal and radial growth. Investigation of the formation, length, and arrangement of lines of arrested growth reveals that the first line is present only in the middle 25-35% of the length of the diaphysis of an adult bone; therefore, only the central portion of the diaphysis should be used for age estimation in skeletochronological studies. Comparison of the shapes and histological structures of epiphyses in the femur, metatarsal bones, and phalanges revealed that epiphyseal cartilages are composed of an inner and outer part. The inner metaphyseal cartilage has distinct zones and plugs the end of the periosteal bone cylinder; its role in longitudinal growth is questioned. The outer epiphyseal cartilage is composed of articular cartilages proper, in addition to lateral articular cartilages. Differences in the symmetry of the lateral articular cartilages of distal epiphyses of the femur and toes may reflect adaptations to different kinds of movements at the knee and in the foot.

  20. Highly complex mitochondrial DNA genealogy in an endemic Japanese subterranean breeding brown frog Rana tagoi (Amphibia, Anura, Ranidae).

    PubMed

    Eto, Koshiro; Matsui, Masafumi; Sugahara, Takahiro; Tanaka-Ueno, Tomoko

    2012-10-01

    The endemic Japanese frog Rana tagoi is unique among Holarctic brown frogs in that it breeds in small subterranean streams. Using mitochondrial 16S ribosomal RNA and NADH dehydrogenase subunit 1 genes, we investigated genealogical relationships among geographic samples of this species together with its relative R. sakuraii, which is also a unique stream breeder. These two species together form a monophyletic group, within which both are reciprocally paraphyletic. Rana tagoi is divided into two major clades (Clade A and B) that are composed of 14 genetic groups. Rana sakuraii is included in Clade A and split into two genetic groups, one of which forms a clade (Subclade A-2) with sympatric R. tagoi. This species-level paraphyly appears to be caused by incomplete taxonomy, in addition to introgressive hybridization and/or incomplete lineage sorting. Rana tagoi strongly differs from other Japanese anurans in its geographic pattern of genetic differentiation, most probably in relation to its unique reproductive habits. Taxonomically, R. tagoi surely includes many cryptic species.

  1. First record of the tree-frog genus Chiromantis from Borneo with the description of a new species (Amphibia: Rhacophoridae).

    PubMed

    Matsui, Masafumi; Shimada, Tomohiko; Sudin, Ahmad

    2014-01-01

    We record a tree frog of the genus Chiromantis for the first time from outside the Southeast Asian continent and describe it as a new species, Chiromantis inexpectatus. The new species from the Malaysian state of Sabah, Borneo, is a small-sized Chiromantis (male snout-vent length ca. 22 mm), and is distinguished from all other members of the genus by the combination of the following morphological characteristics: dark stripes absent, but dark spots present on dorsum; a dark-brown lateral band present from snout tip to half of body, bordered ventrally by white stripe; third and fourth fingers less than half webbed; third finger disk wider than tympanum diameter; and inner metatarsal tubercle present. Significance of findings of this species from Borneo Island, as well as phylogeny and breeding habit of the genus Chiromantis, are briefly discussed.

  2. A new golden frog species of the genus Diasporus (Amphibia, Eleutherodactylidae) from the Cordillera Central, western Panama

    PubMed Central

    Hertz, Andreas; Hauenschild, Frank; Lotzkat, Sebastian; Köhler, Gunther

    2012-01-01

    Abstract We describe the frog species Diasporus citrinobapheus sp. n. from the Cordillera Central of western Panama. The new species differs from all other species in its genus in coloration, disk cover and disk pad shape, skin texture, advertisement call, and size. It is most similar to Diasporus tigrillo, from which it differs in dorsal skin texture, relative tibia length, number of vomerine teeth, ventral coloration, dorsal markings, and relative tympanum size, and to Diasporus gularis, from which it can be distinguished by the lack of membranes between the toes, adult size, posterior thigh coloration, and position of the choanae. We provide data on morpho- logy, vocalization, and distribution of the new species, as well as brief information on its natural history. PMID:22679389

  3. Description of the tadpoles of three rare species of megophryid frogs (Amphibia: Anura: Megophryidae) from Gunung Mulu, Sarawak, Malaysia.

    PubMed

    Oberhummer, Evelyne; Barten, Catherin; Schweizer, Manuel; Das, Indraneil; Haas, Alexander; Hertwig, Stefan T

    2014-07-09

    The megophryid frogs Leptobrachella brevicrus, Leptolalax dringi and Megophrys dringi are species exclusively known  from highly localised areas in isolated mountain ranges on Borneo. The tadpoles and adults in this study were collected at the shared type locality for the three species in Gunung Mulu National Park, Sarawak, Malaysia (Borneo). The species identities of larvae were determined via comparison to syntopic adults using DNA barcoding techniques based on partial 16S rRNA mitochondrial gene sequences. The genetic data supported the status of the three taxa as valid species. Descriptions of colouration in life and after preservation, external morphological features, morphometric measurements and ecological notes in comparison to congeneric species are supplied. The tadpoles of L. brevicrus and L. dringi show similar adaptations to a fossorial lifestyle. These include an elongated, vermiform body, a relatively long tail and small eyes. Both were found in the gravel beds of a small mountain stream. In contrast, the larvae of M. dringi are adapted to occupying and feeding at the surface of pools within the stream. 

  4. Ultrastructure variation in the spermatozoa of Pseudopaludicola frogs (Amphibia, Anura, Leptodactylidae), with brief comments on its phylogenetic relevance.

    PubMed

    dos Santos, Julio Sérgio; Introíni, Gisele Orlandi; Veiga-Menoncello, Ana Cristina Prado; Recco-Pimentel, Shirlei Maria

    2015-12-01

    The taxonomic history of the small frogs of the genus Pseudopaludicola from South America has been controversial. Phylogenetic inferences based on molecular data have identified four Pseudopaludicola clades, correlating with the known variation in karyotypes (2n = 22, 20, 18, and 16). In this study, the ultrastructure of the spermatozoa was analyzed in 12 species of the Pseudopaludicola, with the aim of describing their morphology and identifying characters that may contribute to a better understanding of the phylogenetic relationships. The spermatozoa presented marked differences in tail structures. The tails of the spermatozoa of the species with 2n = 22 chromosomes (Pseudopaludicola sp. 1 [P. pusilla group], Pseudopaludicola falcipes, P. mineira, and Pseudopaludicola saltica), as well as Pseudopaludicola ameghini and Pseudopaludicola ternetzi (2n=20), have juxta-axonemal fibers, undulating membranes and axial fibers. In contrast, in the species with 2n = 18 (P. facureae, P. giarettai, Pseudopaludicola canga, P. atragula, and Pseudopaludicola sp. 2) and 2n = 16 (Pseudopaludicola mystacalis), there are no evident axial or juxta-axonemal fibers, but a paraxonemal rod with a thick undulating membrane, which is shorter than that found among Pseudopaludicola species. The ultrastructural morphological differences observed in the spermatozoa of these species may be phylogenetically informative, given that they coincide with the consensus phylogeny of the group and appear to represent a progressive simplification of the spermatozoon.

  5. Conservation genetics of evolutionary lineages of the endangered mountain yellow-legged frog, Rana muscosa (Amphibia: Ranidae), in southern California

    USGS Publications Warehouse

    Schoville, Sean D.; Tustall, Tate S.; Vredenburg, Vance T.; Backlin, Adam R.; Gallegos, Elizabeth; Wood, Dustin A.; Fisher, Robert N.

    2011-01-01

    Severe population declines led to the listing of southern California Rana muscosa (Ranidae) as endangered in 2002. Nine small populations inhabit watersheds in three isolated mountain ranges, the San Gabriel, San Bernardino and San Jacinto. One population from the Dark Canyon tributary in the San Jacinto Mountains has been used to establish a captive breeding population at the San Diego Zoo Institute for Conservation Research. Because these populations may still be declining, it is critical to gather information on how genetic variation is structured in these populations and what historical inter-population connectivity existed between populations. Additionally, it is not clear whether these populations are rapidly losing genetic diversity due to population bottlenecks. Using mitochondrial and microsatellite data, we examine patterns of genetic variation in southern California and one of the last remaining populations of R. muscosa in the southern Sierra Nevada. We find low levels of genetic variation within each population and evidence of genetic bottlenecks. Additionally, substantial population structure is evident, suggesting a high degree of historical isolation within and between mountain ranges. Based on estimates from a multi-population isolation with migration analysis, these populations diversified during glacial episodes of the Pleistocene, with little gene flow during population divergence. Our data demonstrate that unique evolutionary lineages of R. muscosa occupy each mountain range in southern California and should be managed separately. The captive breeding program at Dark Canyon is promising, although mitigating the loss of neutral genetic diversity relative to the natural population might require additional breeding frogs.

  6. An evaluation of transcriptome-based exon capture for frog phylogenomics across multiple scales of divergence (Class: Amphibia, Order: Anura).

    PubMed

    Portik, Daniel M; Smith, Lydia L; Bi, Ke

    2016-09-01

    Custom sequence capture experiments are becoming an efficient approach for gathering large sets of orthologous markers in nonmodel organisms. Transcriptome-based exon capture utilizes transcript sequences to design capture probes, typically using a reference genome to identify intron-exon boundaries to exclude shorter exons (<200 bp). Here, we test directly using transcript sequences for probe design, which are often composed of multiple exons of varying lengths. Using 1260 orthologous transcripts, we conducted sequence captures across multiple phylogenetic scales for frogs, including outgroups ~100 Myr divergent from the ingroup. We recovered a large phylogenomic data set consisting of sequence alignments for 1047 of the 1260 transcriptome-based loci (~561 000 bp) and a large quantity of highly variable regions flanking the exons in transcripts (~70 000 bp), the latter improving substantially by only including ingroup species (~797 000 bp). We recovered both shorter (<100 bp) and longer exons (>200 bp), with no major reduction in coverage towards the ends of exons. We observed significant differences in the performance of blocking oligos for target enrichment and nontarget depletion during captures, and differences in PCR duplication rates resulting from the number of individuals pooled for capture reactions. We explicitly tested the effects of phylogenetic distance on capture sensitivity, specificity, and missing data, and provide a baseline estimate of expectations for these metrics based on a priori knowledge of nuclear pairwise differences among samples. We provide recommendations for transcriptome-based exon capture design based on our results, cost estimates and offer multiple pipelines for data assembly and analysis.

  7. Effects of subsidy quality on reciprocal subsidies: how leaf litter species changes frog biomass export.

    PubMed

    Earl, Julia E; Castello, Paula O; Cohagen, Kara E; Semlitsch, Raymond D

    2014-05-01

    Spatial subsidies are resources transferred from one ecosystem to another and which can greatly affect recipient systems. Increased subsidy quantity is known to increase these effects, but subsidy quality is likely also important. We examined the effects of leaf litter quality (varying in nutrient and tannin content) in pond mesocosms on gray treefrog (Hyla versicolor) biomass export, as well as water quality and ecosystem processes. We used litter from three different tree species native to Missouri [white oak (Quercus alba), northern red oak (Quercus rubra), and sugar maple (Acer saccharum)], one non-native tree [white pine (Pinus strobus)], and a common aquatic grass [prairie cordgrass (Spartina pectinata)]. We found that leaf litter species affected almost every variable we measured. Gray treefrog biomass export was greatest in mesocosms with grass litter and lowest with white oak litter. Differences in biomass export were affected by high tannin concentrations (or possibly the correlated variable, dissolved oxygen) via their effects on survival, and by primary production, which altered mean body mass. Effects of litter species could often be traced back to the characteristics of the litter itself: leaf nitrogen, phosphorus, and tannin content, which highlights the importance of plant functional traits in affecting aquatic ecosystems. This work and others stress that changes in forest species composition could greatly influence aquatic systems and aquatic-terrestrial linkages.

  8. [Analysis of helminthofauna of common spaedfoot Pelobates fuscus (Laurenti, 1768) and moor frog Rana arvalis Nilsson, 1842 (Amphibia: Anura) at their joint habitation].

    PubMed

    Ruchin, A B; Chikhliaev, I V; Lukiianov, S V

    2009-01-01

    The helminths fauna of common spaedfoot Pelobates fuscus (Laurenti, 1768) and moor frog Rana arvalis Nilsson, 1842 has been studied at their joint habitation. The stuff was collected in 1998-2002, 2004-2006 years in several regions (republic Mordovia, Samara and Saratov areas). The processing of a stuff is conducted by a method of full helmintologic dissecting. The fauna of helminths considerably differs. For common spaedfoot only 13 species of helminths was detected which also parasitized moor frog (for moor frog 23 species) are detected. The index Jaccar demonstrated mean resemblance structure of helminths and varied from 0.25 till 0.69, and the index Morisite--from 44.58 of % till 74.51 of %. The communities of parasites of common spaedfoot was characterized by low values of an index of Shannon, but the high indexes of an index Simpson, whereas for moor frog tracked the return tendence.

  9. B-esterase activities and blood cell morphology in the frog Leptodactylus chaquensis (Amphibia: Leptodactylidae) on rice agroecosystems from Santa Fe Province (Argentina).

    PubMed

    Attademo, Andrés M; Cabagna-Zenklusen, Mariana; Lajmanovich, Rafael C; Peltzer, Paola M; Junges, Celina; Bassó, Agustín

    2011-01-01

    Activity of B-esterases (BChE: butyrylcholinesterase and CbE: carboxylesterase using two model substrates: α-naphthyl acetate and 4-nitrophenyl valerate) in a native frog, Leptodactylus chaquensis from rice fields (RF1: methamidophos and RF2: cypermethrin and endosulfan sprayed by aircraft) and non-contaminated area (pristine forest) was measured. The ability of pyridine-2-aldoxime methochloride (2-PAM) to reactivate BChE levels was also explored. In addition, changes in blood cell morphology and parasite infection were determined. Mean values of plasma BChE activities were lower in samples from the two rice fields than in those from the reference site. CbE (4-nitrophenyl valerate) levels varied in the three sites studied, being highest in RF1. Frog plasma from RF1 showed positive reactivation of BChE activity after incubation with 2-PAM. Blood parameters of frogs from RF2 revealed morphological alterations (anisochromasia and immature erythrocytes frequency). Moreover, a major infection of protozoan Trypanosoma sp. in individuals from the two rice fields was detected. We suggest that integrated use of several biomarkers (BChE and CBEs, chemical reactivation of plasma with 2-PAM, and blood cell parameters) may be a promising procedure for use in biomonitoring programmes to diagnose pesticide exposure of wild populations of this frog and other native anuran species in Argentina.

  10. Morphological and ultrastructural characteristics of Myxobolus ridibundae n. sp. (Myxosporea: Bivalvulida) infecting the testicular tissue of the marsh frog Rana ridibunda (Amphibia: Ranidae) in Egypt.

    PubMed

    Abdel-Ghaffar, Fathy; Abdel-Gaber, Rewaida; Maher, Sherein; El Deeb, Nashwa; Kamel, Reem; Al Quraishy, Saleh; Mehlhorn, Heinz

    2017-01-01

    Myxozoans are one of the most economically important groups of protozoan parasites causing many serious diseases of their hosts. In the present study, a total of 60 live adult male specimens of the marsh frog Rana ridibunda have been randomly captured during the period of January-December 2015 in different areas at Kafr El-Sheikh Governorate, Egypt and were examined for infection by myxosporidian parasites. A total of 48 (80.0 %) out of 60 frog specimens were found to be infected with Myxobolus species. Parasitic infection was restricted to the testicular tissue of the examined frogs. Macroscopic cysts (plasmodia) which heavily infested different parts of the testes were recovered. Morphological and ultrastructural characteristics of these myxosporidian species were carried out using light and transmission electron microscopy. Plasmodia measured 0.16-0.53 (0.34 ± 0.01) mm in diameter. Mature spores appeared oval in frontal view, measuring 8.9-11.5 (9.6 ± 0.1) μm in length and 7.5-9.1 (8.4 ± 0.1) μm in width containing 5-6 turns of polar filaments. Morphometric characterization revealed that the very small size of the present Myxobolus species was the most distinctive feature that separates them from all previously described Myxobolus species. Ultrastructural analysis showed that the plasmodia are surrounded by a plasma membrane with numerous pinocytotic protrusions extending toward the host cell. The generative cells and the different developmental stages are arranged at the periphery of the plasmodia, while immature and mature spores are centrally located. Sporogenesis, capsulogenesis, valvogenesis, and spore maturation of the present parasite are also described. The present species is described as Myxobolus ridibundae and represents a new species.

  11. Mud-packing frog: a novel breeding behaviour and parental care in a stream dwelling new species of Nyctibatrachus (Amphibia, Anura, Nyctibatrachidae).

    PubMed

    Gururaja, Kotambylu Vasudeva; Dinesh, K P; Priti, H; Ravikanth, G

    2014-05-16

    Reproductive modes are diverse and unique in anurans. Selective pressures of evolution, ecology and environment are attributed to such diverse reproductive modes. Globally forty different reproductive modes in anurans have been described to date. The genus Nyctibatrachus has been recently revised and belongs to an ancient lineage of frog families in the Western Ghats of India. Species of this genus are known to exhibit mountain associated clade endemism and novel breeding behaviours. The purpose of this study is to present unique reproductive behaviour, oviposition and parental care in a new species Nyctibatrachus kumbara sp. nov. which is described in the paper. Nyctibatrachus kumbara sp. nov. is a medium sized stream dwelling frog. It is distinct from the congeners based on a suite of morphological characters and substantially divergent in DNA sequences of the mitochondrial 16S rRNA gene. Males exhibit parental care by mud packing the egg clutch. Such parental care has so far not been described from any other frog species worldwide. Besides this, we emphasize that three co-occurring congeneric species of Nyctibatrachus, namely N. jog, N. kempholeyensis and Nyctibatrachus kumbara sp. nov. from the study site differ in breeding behaviour, which could represent a case of reproductive character displacement. These three species are distinct in their size, call pattern, reproductive behaviour, maximum number of eggs in a clutch, oviposition and parental care, which was evident from the statistical analysis. The study throws light on the reproductive behaviour of Nyctibatrachus kumbara sp. nov. and associated species to understand the evolution and adaptation of reproductive modes of anurans in general, and Nyctibatrachus in particular from the Western Ghats.

  12. Adaptations of the reed frog Hyperolius viridiflavus (Amphibia, Anura, Hyperoliidae) to its arid environment : I. The skin of Hyperolius viridiflavus nitidulus in wet and dry season conditions.

    PubMed

    Kobelt, Frank; Linsenmair, K E

    1986-03-01

    Hyperolius viridiflavus nitidulus inhabits parts of the seasonally very hot and dry West African savanna. During the long lasting dry season, the small frog is sitting unhidden on mostly dry plants and has to deal with high solar radiation load (SRL), evaporative water loss (EWL) and small energy reserves. It seems to be very badly equipped to survive such harsh climatic conditions (unfavorable surface to volume ratio, very limited capacity to store energy and water). Therefore, it must have developed extraordinary efficient mechanisms to solve the mentioned problems. Some of these mechanisms are to be looked for within the skin of the animal (e.g. protection against fast desiccation, deleterious effects of UV radiation and overheating). The morphology of the wet season skin is, in most aspects, that of a "normal" anuran skin. It differs in the organization of the processes of the melanophores and in the arrangement of the chromatophores in the stratum spongiosum, forming no "Dermal Chromatophore Unit". During the adaptation to dry season conditions the number of iridophores in dorsal and ventral skin is increased 4-6 times compared to wet season skin. This increase is accompanied by a very conspicuous change of the wet season color pattern. Now, at air temperatures below 35° C the color becomes brownish white or grey and changes to a brilliant white at air temperatures near and over 40° C. Thus, in dry season state the frog retains its ability for rapid color change. In wet season state the platelets of the iridophores are irregularly distributed. In dry season state many platelets become arranged almost parallel to the surface. These purine crystals probably act as quarter-wave-length interference reflectors, reducing SRL by reflecting a considerable amount of the radiated energy input.EWL is as low as that of much larger xeric reptilians. The impermeability of the skin seems to be the result of several mechanisms (ground substance, iridophores, lipids, mucus

  13. [The correlation of the ecological niches of the common (Rana temporaria L.) and of the moor (Rana arvalis Nilss.) frogs (Anura, Amphibia)].

    PubMed

    Severtsov, A S; Liapkov, S M; Surova, G S

    1998-01-01

    During 25 years ecology and population dynamic of two brown frog species (Rana temporaria and R. arvalis) were studied in Moscow region, Solovki island and South Ural. We compared life cycles characteristics, namely biotope preferences, diet, migration, enemies, hibernation places using own and available literature data. Then we analyse how these parameters are changed among the species area and ecological niches were compared. We found that these two species do not compete in any stage of life cycle. Ecological niches are very closed and differences are determined generally by abiotic factors. So, R. temporaria prefers more wet biotope and more sensitive to acidity (low pH value). Differences in spawning time do not associate with interference in spawning places. We conclude that interspecific competition did not take place neither in the past nor in present and the reason of differences in ecological niches are determined by separate ways of evolutionary development of these species.

  14. A new species of limestone karst inhabiting forest frog, genus Platymantis (Amphibia: Anura: Ceratobatrachidae: subgenus Lupacolus) from southern Luzon Island, Philippines.

    PubMed

    Brown, Rafe M; De Layola, Louise Abigail; Lorenzo, Antonio; Diesmos, Mae Lowe L; Diesmos, Arvin C

    2015-11-25

    We describe a new species of limestone karst dwelling forest frog of the genus Platymantis from the Quezon Protected Landscape in southeastern Luzon Island, Philippines. We assign Platymantis quezoni, sp. nov., to the diverse assemblage of terrestrial species in the Platymantis dorsalis Group, subgenus Lupacolus on the basis of its body size and proportions, only slightly expanded terminal discs of the fingers and toes, and its terrestrial microhabitat. The new species is distinguished from these and all other Philippine congeners by features of its external morphology, its restriction to a distinctive limestone karst microhabitat, and its advertisement call, which is unique among frogs of the family Ceratobatrachidae. Several distinguishing morphological characters include its moderate body size (22.1-33.9 mm SVL for 16 adult males and 32.4-39.7 mm SVL for five adult females), slightly expanded terminal discs of the fingers and toes, smooth skin with limited dermal tuberculation, and a dorsal color pattern of mottled tan to dark brown with black blotches. The new species is the sixth Philippine Platymantis known to occur exclusively on limestone karst substrates (previously known karst-obligate species include: P. bayani, P. biak, P. insulatus, P. paengi, and P. speleaus). Recently accelerated discovery of limestone karst anurans across the Philippines suggests that numerous additional species may await discovery on the hundreds of scattered karst formations throughout the archipelago. This possibility suggests that a major conservation priority in coming years will be to study, characterize, describe, and preserve the endemic species supported by this patchy, unique and imperiled type of forest ecosystem in the Philippines.

  15. Three new species of horned frogs, Megophrys (Amphibia: Megophryidae), from northeast India, with a resolution to the identity of Megophrys boettgeri populations reported from the region.

    PubMed

    Mahony, Stephen; Teeling, Emma C; Biju, S D

    2013-01-01

    Northeast India is a well-established region of biological importance but remains poorly understood with regards to the species level identifications of many of its extant amphibians. In this study we examined small sized frogs from the genus Megophrys recently collected from remote and suburban forests in the northeast Indian states of Meghalaya and Arunachal Pradesh, from which we have identified three new species. Megophrys vegrandis sp. nov., Megophrys ancrae sp. nov. and Megophrys oropedion sp. nov. are compared with all known congeners from India and surrounding regions from which they differ based primarily on a combination of morphological characters. Megophrys boettgeri is removed, and Megophrys minor added to the Indian amphibian checklist, through critical review of all literature pertaining to the former species, and the discovery of an overlooked historical report of the latter species. Two of the new species, Megophrys ancrae sp. nov. and Megophrys vegrandis sp. nov. are known from low and mid elevations within two large protected forests in Arunachal Pradesh, both with poorly studied amphibian fauna. Contrastingly, Megophrys oropedion sp. nov. is currently known only from small forested areas on the upper reaches of the Shillong Plateau. The importance of the Shillong Plateau as an area of known high amphibian endemicity is highlighted in the light of the miniscule proportion of its land area afforded government protection, raising concerns about the future conservation of its still poorly known species.

  16. High genetic diversity but low population structure in the frog Pseudopaludicola falcipes (Hensel, 1867) (Amphibia, Anura) from the Pampas of South America.

    PubMed

    Langone, José A; Camargo, Arley; de Sá, Rafael O

    2016-02-01

    Relative to South America's ecoregions, the temperate grasslands of the Pampas have been poorly studied from a phylogeographic perspective. Based on an intermediate biogeographic setting between subtropical forest (Atlantic Forest) and arid ecosystems (Chaco and Patagonia), Pampean species are expected to show unstable demographic histories due to the Quaternary climatic oscillations. Herein, we investigate the phylogenetic relatedness and phylogeographic history of Pseudopaludicola falcipes, a small and common frog that is widely distributed across the Pampean grasslands. First, we use molecular data to assess if P. falcipes represents a single or multiple, separately evolving cryptic lineages. Because P. falcipes is a small-size species (<20mm) with extensive coloration and morphological variation, we suspected that it might represent a complex of cryptic species. In addition, we expected strong genetic and geographic structuring within Pseudopaludicola falcipes due to its large geographic distribution, potentially short dispersal distances, and multiple riverine barriers. We found that P. falcipes is a single evolutionary lineage with poor geographic structuring. Furthermore, current populations of P. falcipes have a large effective population size, maintain ancestral polymorphisms, and have a complex network of gene flow. We conclude that the demographic history of P. falcipes, combined with its ecological attributes and the landscape features of the Pampas, favored a unique combination among anurans of small body size, large population size, high genetic variability, but high cohesiveness of populations over a wide geographic distribution. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. A large-scale phylogeny of Amphibia including over 2800 species, and a revised classification of extant frogs, salamanders, and caecilians.

    PubMed

    Pyron, R Alexander; Wiens, John J

    2011-11-01

    The extant amphibians are one of the most diverse radiations of terrestrial vertebrates (>6800 species). Despite much recent focus on their conservation, diversification, and systematics, no previous phylogeny for the group has contained more than 522 species. However, numerous studies with limited taxon sampling have generated large amounts of partially overlapping sequence data for many species. Here, we combine these data and produce a novel estimate of extant amphibian phylogeny, containing 2871 species (∼40% of the known extant species) from 432 genera (∼85% of the ∼500 currently recognized extant genera). Each sampled species contains up to 12,712 bp from 12 genes (three mitochondrial, nine nuclear), with an average of 2563 bp per species. This data set provides strong support for many groups recognized in previous studies, but it also suggests non-monophyly for several currently recognized families, particularly in hyloid frogs (e.g., Ceratophryidae, Cycloramphidae, Leptodactylidae, Strabomantidae). To correct these and other problems, we provide a revised classification of extant amphibians for taxa traditionally delimited at the family and subfamily levels. This new taxonomy includes several families not recognized in current classifications (e.g., Alsodidae, Batrachylidae, Rhinodermatidae, Odontophrynidae, Telmatobiidae), but which are strongly supported and important for avoiding non-monophyly of current families. Finally, this study provides further evidence that the supermatrix approach provides an effective strategy for inferring large-scale phylogenies using the combined results of previous studies, despite many taxa having extensive missing data.

  18. Evolutionary history and population genetic structure of the endemic tree frog Hyla tsinlingensis (Amphibia: Anura: Hylidae) inferred from mitochondrial gene analysis.

    PubMed

    Zhang, Yan-Hua; Zhao, Yan-Yu; Li, Xue-Ying; Li, Xiao-Chen

    2016-01-01

    The influence of topography and Pleistocenic climatic fluctuations on the population genetic structure of amphibians in the Tsinling-Dabieshan Mountains of China is poorly investigated. Hyla tsinlingensis is a tree frog endemic to the Tsinling-Dabieshan Mountains, with a restricted and patchy distribution that is currently shrinking. We speculated on the evolutionary history of amphibians in this region by studying the population genetic structure of H. tsinlingensis. Using a total of 212 samples, 32 haplotypes and four haplogroups were found in the present study. Population genetic structure showed significant differentiation (F(ST)) between most populations of H. tsinlingensis in the Tsinling-Dabieshan Mountains. An analysis of molecular variance (AMOVA) suggested that most of the observed genetic variation occurs between the two regions (the Tsinling and Dabieshan Mountains). Mantel tests indicated that the genetic divergence was induced through isolation by distance. Using Monmonier's maximum difference algorithm to predict the genetic barrier, two putative barriers in gene flow that separate lineages of H. tsinlingensis were identified. Mismatch distribution and neutrality tests found a sudden population expansion in all haplogroups except the Tsinling population and total population. This population expansion was identified between 0.5 Myr to 0.1 Myr (Quaternary) by Bayesian skyline plot (BSP). Divergence dating indicated the divergence time between the Tsinling population and Dabieshan population to be 3.26 MYA (Pliocene). In conclusion, the topography of the Tsinling and Dabieshan Mountains exerts a significant impact on the population genetic structure of H. tsinlingensis, and climatic oscillations during glacial periods in the Quaternary affected the distribution of H. tsinlingensis.

  19. Molecular phylogeny and genetic identification of populations of two species of Feirana frogs (Amphibia: Anura, Ranidae, Dicroglossinae, Paini) endemic to China.

    PubMed

    Wang, Bin; Jiang, Jianping; Xie, Feng; Chen, Xiaohong; Dubois, Alain; Liang, Gang; Wagner, Steven

    2009-07-01

    Using mitochondrial 12S rRNA, 16S rRNA, and ND2 sequences, we investigated phylogenetic relationships among populations of two frog species endemic to China, both referred to the genus Feirana. A sister-group relationship between the two species was supported moderately in a maximum likelihood analysis and significantly in a Bayesian analysis, but not in a maximum parsimony analysis, of combined data for the three genes. Pending resolution of this incongruence, we provisionally maintain these species in the genus Feirana. Two major clades with a deep divergence are concordant with the species F. quadranus and "F." taihangnica. In the present work, some populations from the Qinling Mountains and all those from the Funiu and the Zhongtiao-southern Taihang Mountains are referred to "F." taihangnica rather than F. quadranus, whereas others are referred to F. quadranus. Consequently, the main body of the Qinling Mountains was identified as a large contact zone between these two species. On the basis of phylogenetic relationships and the distribution pattern of populations, we propose a hypothesis for the divergence of "F." taihangnica: the ancestral species might have inhabited the westernmost Qinling Mountains and dispersed to the main Qinling Mountains, and then to the Zhongtiao-southern Taihang and Funiu Mountains. In contrast, two alternative hypotheses are suggested for F. quadranus: if the two species are confirmed as sister groups, F. quadranus might have dispersed from the westernmost Qinling to the Longmen, Qinling, Daba, and northern Wuling Mountains; alternatively, F. quadranus might have come from the northern Wuling Mountains and then dispersed to the Daba, Qinling, and Longmen mountains.

  20. Phylogeny and Differentiation of Wide-Ranging Ryukyu Kajika Frog Buergeria japonica (Amphibia: Rhacophoridae): Geographic Genetic Pattern Not Simply Explained by Vicariance Through Strait Formation.

    PubMed

    Tominaga, Atsushi; Matsui, Masafumi; Eto, Koshiro; Ota, Hidetoshi

    2015-06-01

    habitats than other frogs.

  1. Cryptic diversity in Amazonian frogs: Integrative taxonomy of the genus Anomaloglossus (Amphibia: Anura: Aromobatidae) reveals a unique case of diversification within the Guiana Shield.

    PubMed

    Vacher, Jean-Pierre; Kok, Philippe J R; Rodrigues, Miguel T; Lima, Jucivaldo Dias; Lorenzini, Andy; Martinez, Quentin; Fallet, Manon; Courtois, Elodie A; Blanc, Michel; Gaucher, Philippe; Dewynter, Maël; Jairam, Rawien; Ouboter, Paul; Thébaud, Christophe; Fouquet, Antoine

    2017-07-01

    Lack of resolution on species boundaries and distribution can hamper inferences in many fields of biology, notably biogeography and conservation biology. This is particularly true in megadiverse and under-surveyed regions such as Amazonia, where species richness remains vastly underestimated. Integrative approaches using a combination of phenotypic and molecular evidence have proved extremely successful in reducing knowledge gaps in species boundaries, especially in animal groups displaying high levels of cryptic diversity like amphibians. Here we combine molecular data (mitochondrial 16S rRNA and nuclear TYR, POMC, and RAG1) from 522 specimens of Anomaloglossus, a frog genus endemic to the Guiana Shield, including 16 of the 26 nominal species, with morphometrics, bioacoustics, tadpole development mode, and habitat use to evaluate species delineation in two lowlands species groups. Molecular data reveal the existence of 18 major mtDNA lineages among which only six correspond to described species. Combined with other lines of evidence, we confirm the existence of at least 12 Anomaloglossus species in the Guiana Shield lowlands. Anomaloglossus appears to be the only amphibian genus to have largely diversified within the eastern part of the Guiana Shield. Our results also reveal strikingly different phenotypic evolution among lineages. Within the A. degranvillei group, one subclade displays acoustic and morphological conservatism, while the second subclade displays less molecular divergence but clear phenotypic divergence. In the A. stepheni species group, a complex evolutionary diversification in tadpole development is observed, notably with two closely related lineages each displaying exotrophic and endotrophic tadpoles. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. The authorships and dates of the specific nomina Megophrys shuichengensis and Pseudohynobius shuichengensis (Amphibia).

    PubMed

    Ohler, Annemarie; Frétey, Thierry; Dubois, Alain

    2015-05-28

    Two amphibian species from China are designated by the specific nomen shuichengensis, which refers to the Shuicheng County (26°34'N, 104°51'E), south of the city of Liupanshui in the province of Guizhou: Megophrys shuichengensis (Amphibia, Anura) and Pseudohynobius shuichengensis (Amphibia, Urodela). The holotypes (holophoronts) of both species were deposited in Department of Biology of the Liupanshui Teachers Higher College (LTHC below). Both species share the particularity of having been described as new twice, at different dates, in different journals and with different authorships. Although this has been acknowledged for the salamander, it has not yet been so for the frog.

  3. Co-Occurrence Patterns of Common and Rare Leaf-Litter Frogs, Epiphytic Ferns and Dung Beetles across a Gradient of Human Disturbance

    PubMed Central

    Oldekop, Johan A.; Bebbington, Anthony J.; Truelove, Nathan K.; Tysklind, Niklas; Villamarín, Santiago; Preziosi, Richard F.

    2012-01-01

    Indicator taxa are commonly used to identify priority areas for conservation or to measure biological responses to environmental change. Despite their widespread use, there is no general consensus about the ability of indicator taxa to predict wider trends in biodiversity. Many studies have focused on large-scale patterns of species co-occurrence to identify areas of high biodiversity, threat or endemism, but there is much less information about patterns of species co-occurrence at local scales. In this study, we assess fine-scale co-occurrence patterns of three indicator taxa (epiphytic ferns, leaf litter frogs and dung beetles) across a remotely sensed gradient of human disturbance in the Ecuadorian Amazon. We measure the relative contribution of rare and common species to patterns of total richness in each taxon and determine the ability of common and rare species to act as surrogate measures of human disturbance and each other. We find that the species richness of indicator taxa changed across the human disturbance gradient but that the response differed among taxa, and between rare and common species. Although we find several patterns of co-occurrence, these patterns differed between common and rare species. Despite showing complex patterns of species co-occurrence, our results suggest that species or taxa can act as reliable indicators of each other but that this relationship must be established and not assumed. PMID:22701730

  4. Co-occurrence patterns of common and rare leaf-litter frogs, epiphytic ferns and dung beetles across a gradient of human disturbance.

    PubMed

    Oldekop, Johan A; Bebbington, Anthony J; Truelove, Nathan K; Tysklind, Niklas; Villamarín, Santiago; Preziosi, Richard F

    2012-01-01

    Indicator taxa are commonly used to identify priority areas for conservation or to measure biological responses to environmental change. Despite their widespread use, there is no general consensus about the ability of indicator taxa to predict wider trends in biodiversity. Many studies have focused on large-scale patterns of species co-occurrence to identify areas of high biodiversity, threat or endemism, but there is much less information about patterns of species co-occurrence at local scales. In this study, we assess fine-scale co-occurrence patterns of three indicator taxa (epiphytic ferns, leaf litter frogs and dung beetles) across a remotely sensed gradient of human disturbance in the Ecuadorian Amazon. We measure the relative contribution of rare and common species to patterns of total richness in each taxon and determine the ability of common and rare species to act as surrogate measures of human disturbance and each other. We find that the species richness of indicator taxa changed across the human disturbance gradient but that the response differed among taxa, and between rare and common species. Although we find several patterns of co-occurrence, these patterns differed between common and rare species. Despite showing complex patterns of species co-occurrence, our results suggest that species or taxa can act as reliable indicators of each other but that this relationship must be established and not assumed.

  5. Rhabdias kongmongthaensis sp. n. (Nematoda: Rhabdiasidae) from Polypedates leucomystax (Amphibia: Anura: Rhacophoridae) in Thailand.

    PubMed

    Kuzmin, Yuriy; Tkach, Vasyl V; Vaughan, Jefferson A

    2005-11-01

    Rhabdias kongmongthaensis sp. n. is described based on specimens found in the lungs of the tree frog Polypedates leucomystax (Gravenhorst) (Amphibia: Rhacophoridae) from Kanchanaburi Province, western Thailand. The new species is similar to two North-American species, Rhabdias ranae and R. americanus, by presence of two lateral pseudolabia, each with two inner submedian protuberances. R. kongmongthaensis differs from both species by relative length and shape of the tail, and by its distribution and host specificity. Presence of lateral pseudolabia distinguishes the new species from the geographically closest Rhabdias species as well as from those parasitizing other rhacophorid frogs.

  6. Mitochondrial evidence on the phylogenetic position of caecilians (Amphibia: Gymnophiona).

    PubMed Central

    Zardoya, R; Meyer, A

    2000-01-01

    The complete nucleotide sequence (17,005 bp) of the mitochondrial genome of the caecilian Typhlonectes natans (Gymnophiona, Amphibia) was determined. This molecule is characterized by two distinctive genomic features: there are seven large 109-bp tandem repeats in the control region, and the sequence for the putative origin of replication of the L strand can potentially fold into two alternative secondary structures (one including part of the tRNA(Cys)). The new sequence data were used to assess the phylogenetic position of caecilians and to gain insights into the origin of living amphibians (frogs, salamanders, and caecilians). Phylogenetic analyses of two data sets-one combining protein-coding genes and the other combining tRNA genes-strongly supported a caecilian + frog clade and, hence, monophyly of modern amphibians. These two data sets could not further resolve relationships among the coelacanth, lungfishes, and tetrapods, but strongly supported diapsid affinities of turtles. Phylogenetic relationships among a larger set of species of frogs, salamanders, and caecilians were estimated with a mitochondrial rRNA data set. Maximum parsimony analysis of this latter data set also recovered monophyly of living amphibians and favored a frog + salamander (Batrachia) relationship. However, bootstrap support was only moderate at these nodes. This is likely due to an extensive among-site rate heterogeneity in the rRNA data set and the narrow window of time in which the three main groups of living amphibians were originated. PMID:10835397

  7. Mitochondrial evidence on the phylogenetic position of caecilians (Amphibia: Gymnophiona).

    PubMed

    Zardoya, R; Meyer, A

    2000-06-01

    The complete nucleotide sequence (17,005 bp) of the mitochondrial genome of the caecilian Typhlonectes natans (Gymnophiona, Amphibia) was determined. This molecule is characterized by two distinctive genomic features: there are seven large 109-bp tandem repeats in the control region, and the sequence for the putative origin of replication of the L strand can potentially fold into two alternative secondary structures (one including part of the tRNA(Cys)). The new sequence data were used to assess the phylogenetic position of caecilians and to gain insights into the origin of living amphibians (frogs, salamanders, and caecilians). Phylogenetic analyses of two data sets-one combining protein-coding genes and the other combining tRNA genes-strongly supported a caecilian + frog clade and, hence, monophyly of modern amphibians. These two data sets could not further resolve relationships among the coelacanth, lungfishes, and tetrapods, but strongly supported diapsid affinities of turtles. Phylogenetic relationships among a larger set of species of frogs, salamanders, and caecilians were estimated with a mitochondrial rRNA data set. Maximum parsimony analysis of this latter data set also recovered monophyly of living amphibians and favored a frog + salamander (Batrachia) relationship. However, bootstrap support was only moderate at these nodes. This is likely due to an extensive among-site rate heterogeneity in the rRNA data set and the narrow window of time in which the three main groups of living amphibians were originated.

  8. Adaptations of the reed frog Hyperolius viridiflavus (Amphibia, Anura, Hyperoliidae) to its arid environment. VII. The heat budget of Hyperolius viridiflavus nitidulus and the evolution of an optimized body shape.

    PubMed

    Kobelt, F; Linsenmair, K E

    1995-01-01

    Estivating reed frogs of the superspecies Hyperolius viridiflavus are extraordinarily resistant to the highly adverse climatic conditions prevailing in their African savanna habitats during dry season (air temperature up to 45 degrees C, solar radiation load up to 1000 W.m-2, no water replenishment possible for up to 3 months). They are able to withstand such climatic stress at their exposed estivation sites on dry plants without evaporative cooling. We developed a heat budget model to understand the mechanisms of how an anuran can achieve this unique tolerance, and which allows us to predict the anuran's core and surface temperature for a given set of environmental parameters, to within 4% of the measured values. The model makes it possible to quantify some of the adaptive mechanisms for survival in semiarid habitats by comparing H. viridiflavus with anurans (H. tuberilinguis and Rana pipiens) of less stressful habitats. To minimize heat gain and maximize heat loss from the frog, the following points were important with regard to avoiding lethal heat stress during estivation: 1) solar heat load is reduced by an extraordinarily high skin reflectivity for solar radiation of up to 0.65 under laboratory and even higher in the field under dry season conditions. 2) The half-cylindrical body shape of H. viridiflavus seems to be optimized for estivation compared to the hemispheroidal shape usually found for anurans in moist habitats. A half-cylinder can be positioned relative to the sun so that large surface areas for conductive and convective heat loss are shielded by a small area exposed to direct solar radiation. 3) Another important contribution of body shape is a high body surface area to body mass ratio, as found in the estivating subadult H. viridiflavus (snout-vent lengths of 14-20 mm and body weights of 350-750 mg) compared to adult frogs (24-30 mm, 1000-2500 mg) which have never been observed to survive a dry season. 4) These mechanisms strongly couple core

  9. Leaf litter of invasive Chinese tallow (Triadica sebifera) negatively affects hatching success of an aquatic breeding anuran, the southern leopard frog (Lithobates sphenocephalus)

    Treesearch

    C.K. Adams; D. Saenz

    2012-01-01

    Chinese tallow (Triadica sebifera (L.) Small) is an aggressive invasive tree species that can be abundant in parts of its non-native range. This tree species has the capability of producing monocultures, by outcompeting native trees, which can be in or near wetlands that are utilized by breeding amphibians. Existing research suggests that leaf litter from invasive...

  10. AmphibiaChina: an online database of Chinese Amphibians.

    PubMed

    Che, Jing; Wang, Kai

    2016-01-18

    AmphibiaChina, an open-access, web-based database, is designed to provide comprehensive and up-to-date information on Chinese amphibians. It offers an integrated module with six major sections. Compared to other known databases including AmphibiaWeb and Amphibian Species of the World, AmphibiaChina has the following new functions: (1) online species identification based on DNA barcode sequences; (2) comparisons and discussions of different major taxonomic systems; and (3) phylogenetic progress on Chinese amphibians. This database offers a window for the world to access available information of Chinese amphibians. AmphibiaChina with its Chinese version can be accessed at http://www.amphibiachina.org.

  11. Comparative morphometric study of the vestibular system of the vertebrata: reptilia, aves, amphibia, and pisces.

    PubMed

    Ramprashad, F; Landolt, J P; Money, K E; Laufer, J

    1986-01-01

    Morphometric measurements were made from serial sections of the vestibular system in four classes of vertebrates: Reptilia, Aves, Amphibia, and Pisces. Representative species of reptile studied were the lizard (Gekko gecko), the common garter snake (Thamnophis sp.), and the common turtle (Chelonia sp.). The budgie (Melopsittacus undulatas), the common pigeon (Columba domestica), the yellow-bellied sapsucker (Sphyrapicus varius), and the horned owl (Bubo virginianus) were chosen as representative of the bird. For the amphibian, the leopard frog (Rana pipiens), and the mud puppy (Necturus maculatus) were chosen for study. As representative of the fish, the goldfish (Carassius auratus), the tilapia (Tilapia mossambica), the guppy (Lebistes sp.), and the sea horse (Hippocampus sp.) were used in these measurements. The morphometric data obtained were then used in estimates of the time constants in the Steinhausen equation which describes the biophysics of fluid flow in the semicircular canals. In general, the time constants (theta/II in the Steinhausen equation) of these representatives of Reptilia, Aves, and Amphibia were of magnitude similar to those reported in mammals, despite the dissimilarities in the diameters of the ducts, the duct radii of curvature, the dimensions of the cristae ampullares and the utricle, and volumes of endolymph within the vestibular system. However, the short-time constants in Pisces were larger (therefore providing a slower response) than those in other vertebrates, and were similar to that of the turtle and the mud puppy.

  12. The spleen pigment cells in some amphibia.

    PubMed

    Scalia, Marina; Di Pietro, Cinzia; Poma, Mariangela; Ragusa, Marco; Sichel, Giovanni; Corsaro, Concetta

    2004-04-01

    It was demonstrated that the spleen pigment cells of Amphibia are macrophages: they show an ultrastructurally distinctive morphology, are able to phagocytose and react positively for non-specific esterases. These pigmented macrophages express mRNA for tyrosinase and also they show dopa oxidase activity; therefore they are able to synthesize melanins, as Kupffer cells do.

  13. Fantastic Frogs!

    ERIC Educational Resources Information Center

    Scott, Kym

    2002-01-01

    Number rhymes can be used in many exciting and different ways to support the early learning goals for mathematics. The rhyme "five little speckled frogs" provides the theme for this display, which was set up in Lewisham's professional development center. It provides a range of ideas which would help develop young children's mathematical learning…

  14. Fantastic Frogs!

    ERIC Educational Resources Information Center

    Scott, Kym

    2002-01-01

    Number rhymes can be used in many exciting and different ways to support the early learning goals for mathematics. The rhyme "five little speckled frogs" provides the theme for this display, which was set up in Lewisham's professional development center. It provides a range of ideas which would help develop young children's mathematical learning…

  15. FROGS report

    NASA Astrophysics Data System (ADS)

    FROGS Reports present information on current research relevant to felsic magmatism, including commentaries on problems of current interest. Please contact Calvin Miller, Geology, 6028B, Vanderbilt University, Nashville, TN 37235; tel. 615-322-2986 about your own research, conferences, and ideas for stimulating commentaries.

  16. Morphology, ultrastructure and molecular characterisation of Spiroxys japonica Morishita, 1926 (Spirurida: Gnathostomatidae) from Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae).

    PubMed

    Li, Liang; Hasegawa, Hideo; Roca, Vicente; Xu, Zhen; Guo, Yan-Ning; Sato, Akiko; Zhang, Lu-Ping

    2014-03-01

    Gnathostomatid nematodes identified morphologically as Spiroxys japonica Morishita, 1926 were collected from the dark-spotted frog Pelophylax nigromaculatus (Hallowell) (Amphibia: Ranidae) in China. Light and scanning electron microscopy were used to study the morphology of this species in detail. Previously unreported morphological features are revealed and others corrected. In addition, adult nematodes of S. japonica collected from P. nigromaculatus and Spiroxys hanzaki Hasegawa, Miyata & Doi, 1998 collected from Andrias japonicus (Temminck) (Caudata: Cryptobranchidae) in China and Japan, respectively, and the third-stage larva of S. japonica collected from Lithobates catesbeianus (Shaw) (Anura: Ranidae) in Japan, were characterised using molecular methods by sequencing and analysing ribosomal [large ribosomal DNA (18S) and internal transcribed space] and mitochondrial [cytochrome c oxidase subunit 1] target regions, respectively. The new morphological and genetic data contributes to a more accurate diagnosis of this hitherto little known nematode genus.

  17. Chromosome banding in Amphibia. XVII. First demonstration of multiple sex chromosomes in amphibians: Eleutherodactylus maussi (Anura, leptodactylidae).

    PubMed

    Schmid, M; Steinlein, C; Feichtinger, W

    1992-03-01

    A cytogenetic study performed on a population of the South American leptodactylid frog Eleutherodactylus maussi revealed multiple sex chromosomes of the X1X1X2X2 female/X1X2Y male (= XXAA female/XXAY male) type. The diploid chromosome number is 2n = 36 in all females and 2n = 35 in most males. The multiple sex chromosomes originated by a centric fusion between the original Y chromosome and a large autosome. In male meiosis the X1X2Y (= XXAY) multiple sex chromosomes form a classical trivalent configuration. E. maussi is the first species discovered in the class Amphibia that is distinguished by a system of multiple sex chromosomes. Only one single male was found in the population with 2n = 36 chromosomes and lacking the Y-autosomal fusion. This karyotype (XYAA male) is interpreted as the ancestral condition, preceding the occurrence of the Y-autosome fusion.

  18. The wood frog (Rana sylvatica): a technical conservation assessment

    USGS Publications Warehouse

    Muths, E.; Rittmann, S.; Irwin, J.; Keinath, D.; Scherer, R.

    2005-01-01

    Overall, the wood frog (Rana sylvatica) is ranked G5, secure through most of its range (NatureServe Explorer 2002). However, it is more vulnerable in some states within the USDA Forest Service Region 2: S3 (vulnerable) in Colorado, S2 (imperiled) in Wyoming, and S1 (critically imperiled in South Dakota (NatureServe Explorer 2002); there are no records for wood frogs in Kansas or Nebraska. Primary threats to wood frog populations are habitat fragmentation (loss of area, edge effects, and isolation) and habitat loss due to anthropogenic causes (e.g., wetland draining, grazing) and natural changes as habitat succession occurs. Wood frogs are most conspicuous at breeding sites early in the spring, when snow and ice are often still present at pond margins. They tolerate frezzing and hibernate terrestrially in shallow depressions, under leaf litter, grasses, logs, or rocks (Bagdonas 1968, Bellis 1961a); there are no reports of aquatic hibernation for this species (Licht 1991, Pinder et al. 1992). Wood frogs require semi-permanent and temporary pools of natural origin and adjacent wet meadows, and landscape alterations that shorten the hydroperiod of ponds can result in catastrophic tadpole mortality. Plant communities utilized by wood frogs in the Rocky Mountains are hydric to mesic and include sedge and grass meadows, willow hummocks, aspen groves, lodgepole pine forests, and woodlands with leaf litter and/or herbaceous understory (Maslin 1947, Bellis 1961a, Roberts and Lewin 1979, Haynes and Aird 1981). Wood frogs are likely to disperse into surrounding marsh and woodlands soon after oviposition (Heatwole 1961, Haynes and Aird 1981). In the arly fall, wood frogs begin to seek hibernacula at or just below the ground surface, generally in upland forest habitat (Regosin et al. 2003). Licht (1991) demonstrated shelter-seeking behavior at 1.5 [degrees] C. Once they have concealed themselves for hibernation, wood frogs are very difficult to detecta?|

  19. Characterisation of Kupffer cells in some Amphibia

    PubMed Central

    CORSARO, CONCETTA; SCALIA, MARINA; LEOTTA, NICOLA; MONDIO, FILIPPO; SICHEL, GIOVANNI

    2000-01-01

    A study on the Kupffer cells (KCs) of Amphibia was undertaken in order to compare these cells with those of endothermic animals. Liver tissue and isolated and cultured KCs were studied by light microscopy and by transmission and scanning electron microscopy. We have shown that amphibian KCs can be divided into 2 principal types: ‘small’ and ‘large’. Both cell types possess the distinctive KC morphology. They show nonspecific esterase activity, weak endogenous peroxidase activity in the nuclear envelope and in the rough endoplasmic reticulum, and the ability to engulf naturally present cell debris or experimentally administered zymosan or latex particles. The principal difference between the small and the large cells consists in the substantial quantity of inclusion bodies that exist only in the latter. We conclude that amphibian KCs, apart from their ability to build melanosomes and synthesise melanins, are very similar to mammalian KCs. PMID:10739021

  20. Litter-Spinning Retarders

    NASA Technical Reports Server (NTRS)

    Wilson, John C.

    1995-01-01

    Aerodynamic plates stop litter from spinning during hoisting by helicopter. Features of proposed litter-spinning retarders include convenience of deployment and independence from ground restraint. Retarder plate(s) folded flat against bottom of litter during storage or while litter is loaded. Plate(s) held in storage position by latch that releases manually or automatically as litter is hoisted. Upon release, springs move plates into deployed position.

  1. Litter-Spinning Retarders

    NASA Technical Reports Server (NTRS)

    Wilson, John C.

    1995-01-01

    Aerodynamic plates stop litter from spinning during hoisting by helicopter. Features of proposed litter-spinning retarders include convenience of deployment and independence from ground restraint. Retarder plate(s) folded flat against bottom of litter during storage or while litter is loaded. Plate(s) held in storage position by latch that releases manually or automatically as litter is hoisted. Upon release, springs move plates into deployed position.

  2. Effects of a common insecticide on wetland communities with varying quality of leaf litter inputs.

    PubMed

    Stoler, A B; Mattes, B M; Hintz, W D; Jones, D K; Lind, L; Schuler, M S; Relyea, R A

    2017-07-01

    Chemical contamination of aquatic systems often co-occurs with dramatic changes in surrounding terrestrial vegetation. Plant leaf litter serves as a crucial resource input to many freshwater systems, and changes in litter species composition can alter the attributes of freshwater communities. However, little is known how variation in litter inputs interacts with chemical contaminants. We investigated the ecological effects resulting from changes in tree leaf litter inputs to freshwater communities, and how those changes might interact with the timing of insecticide contamination. Using the common insecticide malathion, we hypothesized that inputs of nutrient-rich and labile leaf litter (e.g., elm [Ulmus spp.] or maple [Acer spp.]) would reduce the negative effects of insecticides on wetland communities relative to inputs of recalcitrant litter (e.g., oak [Quercus spp.]). We exposed artificial wetland communities to a factorial combination of three litter species treatments (elm, maple, and oak) and four insecticide treatments (no insecticide, small weekly doses of 10 μg L(-1), and either early or late large doses of 50 μg L(-1)). Communities consisted of microbes, algae, snails, amphipods, zooplankton, and two species of tadpoles. After two months, we found that maple and elm litter generally induced greater primary and secondary production. Insecticides induced a reduction in the abundance of amphipods and some zooplankton species, and increased phytoplankton. In addition, we found interactive effects of litter species and insecticide treatments on amphibian responses, although specific effects depended on application regime. Specifically, with the addition of insecticide, elm and maple litter induced a reduction in gray tree frog survival, oak and elm litter delayed tree frog metamorphosis, and oak and maple litter reduced green frog tadpole mass. Our results suggest that attention to local forest composition, as well as the timing of pesticide application

  3. Frog eat frog: exploring variables influencing anurophagy

    PubMed Central

    Vimercati, Giovanni; de Villiers, F. André; Mokhatla, Mohlamatsane M.; Davies, Sarah J.; Edwards, Shelley; Altwegg, Res

    2015-01-01

    Background. Frogs are generalist predators of a wide range of typically small prey items. But descriptions of dietary items regularly include other anurans, such that frogs are considered to be among the most important of anuran predators. However, the only existing hypothesis for the inclusion of anurans in the diet of post-metamorphic frogs postulates that it happens more often in bigger frogs. Moreover, this hypothesis has yet to be tested. Methods. We reviewed the literature on frog diet in order to test the size hypothesis and determine whether there are other putative explanations for anurans in the diet of post-metamorphic frogs. In addition to size, we recorded the habitat, the number of other sympatric anuran species, and whether or not the population was invasive. We controlled for taxonomic bias by including the superfamily in our analysis. Results. Around one fifth of the 355 records included anurans as dietary items of populations studied, suggesting that frogs eating anurans is not unusual. Our data showed a clear taxonomic bias with ranids and pipids having a higher proportion of anuran prey than other superfamilies. Accounting for this taxonomic bias, we found that size in addition to being invasive, local anuran diversity, and habitat produced a model that best fitted our data. Large invasive frogs that live in forests with high anuran diversity are most likely to have a higher proportion of anurans in their diet. Conclusions. We confirm the validity of the size hypothesis for anurophagy, but show that there are additional significant variables. The circumstances under which frogs eat frogs are likely to be complex, but our data may help to alert conservationists to the possible dangers of invading frogs entering areas with threatened anuran species. PMID:26336644

  4. A new species of Rhabdias Stiles et Hassall, 1905 (Nematoda: Rhabdiasidae) from Blommersia domerguei (Guibé) (Amphibia: Mantellidae) in Madagascar.

    PubMed

    Kuzmin, Yuriy; Junker, Kerstin; du Preez, Louis; Bain, Odile

    2013-11-01

    Rhabdias blommersiae sp. n. (Nematoda: Rhabdiasidae) is described from the lungs of Domergue's Madagascar frog, Blommersia domerguei (Guibé) (Amphibia: Mantellidae), in Madagascar. The new species differs from congeners parasitizing amphibians in having a smaller body and buccal capsule, six equal lips, large excretory glands of unequal length and a posteriorly inflated body vesicle. A combination of characters distinguishes it from Afromalagasy species of Rhabdias Stiles et Hassall, 1905. Rhabdias blommersiae is the third species of the genus described from amphibians in Madagascar. Close similarities in the number and shape of circumoral structures in two Rhabdias species described from mantellid hosts in Madagascar suggest a close relationship and common origin of the two species, with subsequent adaptation to separate hosts within the Mantellidae.

  5. Yet More Frogs

    ERIC Educational Resources Information Center

    Shutler, Paul M. E.

    2011-01-01

    Extending a recent paper by Derek Holton, we show how to represent the algorithm for the Frog Problem diagrammatically. This diagrammatic representation suggests a simpler proof of the symmetrical case (equal numbers of frogs of each colour) by allowing the even and odd cases to be treated together. It also provides a proof in the asymmetrical…

  6. Yet More Frogs

    ERIC Educational Resources Information Center

    Shutler, Paul M. E.

    2011-01-01

    Extending a recent paper by Derek Holton, we show how to represent the algorithm for the Frog Problem diagrammatically. This diagrammatic representation suggests a simpler proof of the symmetrical case (equal numbers of frogs of each colour) by allowing the even and odd cases to be treated together. It also provides a proof in the asymmetrical…

  7. Yet more frogs

    NASA Astrophysics Data System (ADS)

    Shutler, Paul M. E.

    2011-06-01

    Extending a recent paper by Derek Holton, we show how to represent the algorithm for the Frog Problem diagrammatically. This diagrammatic representation suggests a simpler proof of the symmetrical case (equal numbers of frogs of each colour) by allowing the even and odd cases to be treated together. It also provides a proof in the asymmetrical case (unequal numbers of frogs) as an extension of the symmetrical case. The issue of whether frogs of a given colour should be allowed to move in either direction is discussed. While it is possible to restrict to the case of movement in a single direction, results for bi-directional movement can be obtained by making the correspondence between the algorithm and its diagrammatic representation more concrete. The Frog Problem then becomes a form of constrained shortest path problem around the diagram, and from this point of view optimality of the algorithm becomes much clearer.

  8. A consistent nomenclature of antimicrobial peptides isolated from frogs of the subfamily Phyllomedusinae.

    PubMed

    Amiche, Mohamed; Ladram, Ali; Nicolas, Pierre

    2008-11-01

    A growing number of cationic antimicrobial peptides have been isolated from the skin of hylid frogs belonging to the Phyllomedusinae subfamily. The amino acid sequences of these peptides are currently located in several databases under identifiers with no consistent system of nomenclature to describe them. In order to provide a workable terminology for antimicrobial peptides from Phyllomedusid frogs, we have made a systematic effort to collect, analyze, and classify all the Phyllomedusid peptide sequences available in databases. We propose that frogs belonging to the Phyllomedusinae subfamily should be described by the species names set out in Amphibian Species of the World: http://research.amnh.org/herpetology/amphibia/index.php, American Museum of Natural History, New York, USA. Multiple alignments analysis of at least 80 antimicrobial peptides isolated from 12 Phyllomedusinae species were distributed in seven distinct peptide families including dermaseptin, phylloseptin, plasticin, dermatoxin, phylloxin, hyposin and orphan peptides, and will be considered as the name of the headgroup of each family. The parent peptide's name should be followed by the first upper letter of the species for orthologous peptides and publication date determines priority. For example, the abbreviation B for bicolor and H for hypochondrialis. When two species begin with the same letter, two letters in upper case should be used (the first letter followed by the second or the third letter and so on). For example, the abbreviation DI for distincta, DU for duellmani, VA for vaillanti and VN for vanzolinii. Paralogous peptides should bear letter(s) in upper case followed by numbers.

  9. Environmentally friendly animal litter

    SciTech Connect

    Chett, Boxley; McKelvie, Jessica

    2013-08-20

    A method of making an animal litter that includes geopolymerized ash, wherein, the animal litter is made from a quantity of a pozzolanic ash mixed with a sufficient quantity of water and an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. After the geopolymerized ash is formed, it is dried, broken into particulates, and sieved to a desired size. These geopolymerized ash particulates are used to make a non-clumping or clumping animal litter. Odor control may be accomplished with the addition of a urease inhibitor, pH buffer, an odor eliminating agent, and/or fragrance.

  10. Littering Behavior in Public Places

    ERIC Educational Resources Information Center

    Robinson, Stuart N.

    1976-01-01

    This review summarizes the present state of knowledge concerning littering behavior. Available studies are categorized according to the variables that influence littering--individual and environmental. Theoretical issues of attitude-behavior consistency and incentive effectiveness are analyzed with respect to littering and litter control. Results…

  11. Field Experiments in Litter Control

    ERIC Educational Resources Information Center

    Finnie, William C.

    1973-01-01

    A series of urban and highway litter experiments in Richmond (Virginia), St. Louis, and Philadelphia indicated well-designed litter cans reduced littering about 15 percent along city streets and nearly 30 percent along highways. Also, the propensity to litter is critically affected by the characteristics of the individual and environmental…

  12. Field Experiments in Litter Control

    ERIC Educational Resources Information Center

    Finnie, William C.

    1973-01-01

    A series of urban and highway litter experiments in Richmond (Virginia), St. Louis, and Philadelphia indicated well-designed litter cans reduced littering about 15 percent along city streets and nearly 30 percent along highways. Also, the propensity to litter is critically affected by the characteristics of the individual and environmental…

  13. Littering Behavior in Public Places

    ERIC Educational Resources Information Center

    Robinson, Stuart N.

    1976-01-01

    This review summarizes the present state of knowledge concerning littering behavior. Available studies are categorized according to the variables that influence littering--individual and environmental. Theoretical issues of attitude-behavior consistency and incentive effectiveness are analyzed with respect to littering and litter control. Results…

  14. Species boundaries and taxonomy of the African river frogs (Amphibia: Pyxicephalidae: Amietia).

    PubMed

    Channing, A; Dehling, J M; Lötters, S; Ernst, R

    2016-08-25

    A molecular phylogeny of the Afrotropical anuran genus Amietia based on 323 16S sequences indicates that there are 19 species, including four not yet described. No genetic material was available for the nominal A. inyangae. We consider them to represent full species, and define them based on 16S genetic distances, as well as differences in morphology, tadpoles and advertisement call where known. An analysis based on two mitochondrial and two nuclear genes (12S, 16S, 28S and tyrosinase exon 1), from 122 samples, confirmed the phylogenetic relationships suggested by the 16S tree. We recognise and (re-) describe the following species: Amietia angolensis (Bocage, 1866), A. chapini (Noble, 1924), A. delalandii (Duméril & Bibron, 1841), A. desaegeri (Laurent, 1972), A. fuscigula (Duméril & Bibron, 1841), A. hymenopus (Boulenger, 1920), A. inyangae (Poynton, 1966), A. johnstoni (Günther, 1893), A. moyerorum sp. nov., A. nutti (Boulenger, 1896), A. poyntoni Channing & Baptista, 2013, A. ruwenzorica (Laurent, 1972), A. tenuoplicata (Pickersgill, 2007), A. vandijki (Visser & Channing, 1997), A. vertebralis (Hewitt, 1927), and A. wittei (Angel, 1924). Three further candidate species of Larson et al. (2016) await formal naming. We provisionally regard A. amieti (Laurent, 1976) as a junior synonym of A. chapini (Noble, 1924). Amietia lubrica (Pickersgill, 2007) is shown to be a junior synonym of A. nutti, while A. quecketti (Boulenger, 1895) is shown to be a junior synonym of A. delalandii (Duméril & Bibron, 1841), and A. viridireticulata (Pickersgill, 2007) is placed as a junior synonym of A. tenuoplicata (Pickersgill, 2007). On the basis of similarity of 16S sequences, we assign A. sp. 1, A. sp. 3 and A. sp. 6 of Larson et al (2016) to the nomina A. chapini (Noble, 1924), A. desaegeri (Laurent, 1972), and A. nutti (Boulenger, 1896) respectively.

  15. Reconciling molecular phylogeny, morphological divergence and classification of Madagascan narrow-mouthed frogs (Amphibia: Microhylidae).

    PubMed

    Scherz, Mark D; Vences, Miguel; Rakotoarison, Andolalao; Andreone, Franco; Köhler, Jörn; Glaw, Frank; Crottini, Angelica

    2016-07-01

    A recent study clarified several aspects of microhylid phylogeny by combining DNA sequences from Sanger sequencing and anchored phylogenomics, although numerous aspects of tree topology proved highly susceptible to data partition and chosen model. Although the phylogenetic results of the study were in conflict with previous publications, the authors made several changes to the taxonomy of Madagascar's cophyline microhylids. We re-analyzed part of their data together with our own molecular and morphological data. Based on a supermatrix of 11 loci, we propose a new phylogeny of the Cophylinae, and discuss it in the context of a newly generated osteological dataset. We found several sample misidentifications, partially explaining their deviant results, and propose to resurrect the genera Platypelis and Stumpffia from the synonymy of Cophyla and Rhombophryne, respectively. We provide support for the previous genus-level taxonomy of this subfamily, and erect a new genus, Anilany gen. nov., in order to eliminate paraphyly of Stumpffia and to account for the osteological differences observed among these groups. Deep nodes in our phylogeny remain poorly supported, and future works will certainly refine our classification, but we are confident that these will not produce large-scale rearrangements.

  16. Jan Swammerdam's frogs

    PubMed Central

    Sleigh, Charlotte

    2012-01-01

    Having discussed insect metamorphosis at length, Jan Swammerdam's Bybel der Natuure (1679/1737) reached its climax with a substantial description of the generation and muscular activity of frogs. This paper explores the rhetorical role of frogs in Swammerdam's ‘great work’, showing how they were the Archimedean point from which he aimed to reorder all of creation—from insects to humans—within one glorious, God-ordained natural history and philosophy. Swammerdam linked insects to frogs through a demonstration that all underwent epigenesis; and frogs were then linked to humans through a demonstration of their identical muscular activity. The success of Swammerdam's strategy required a theological reconstruction of the frog, traditionally an ungodly creature, such that trustworthy knowledge could be obtained from its body. Perhaps surprisingly, this act of theological cleansing is shown to be somewhat prefigured in the distinctly non-experimental natural history of Edward Topsell (1608). The paper also examines Swammerdam's interactions with the mystic Antoinette Bourignon, and his challenges in reconciling a spirituality of meletetics with a material epistemology in natural philosophy. Differences are revealed between the natural analogies given by Swammerdam in his published and unpublished writings, undermining to a certain extent the triumphal insect–frog–human rhetorical structure of the Bybel.

  17. The Experimental Control of Littering

    ERIC Educational Resources Information Center

    Clark, Roger N.; And Others

    1972-01-01

    Behavior, incentives, and education programs were researched as factors relating to littering. Experiments in theaters, forest campgrounds, and hiking and dispersed car camping areas indicate incentive systems are necessary and feasible for curbing litter problems. (BL)

  18. The Experimental Control of Littering

    ERIC Educational Resources Information Center

    Clark, Roger N.; And Others

    1972-01-01

    Behavior, incentives, and education programs were researched as factors relating to littering. Experiments in theaters, forest campgrounds, and hiking and dispersed car camping areas indicate incentive systems are necessary and feasible for curbing litter problems. (BL)

  19. It's a Frog's Life

    ERIC Educational Resources Information Center

    Coffey, Audrey L.; Sterling, Donna R.

    2003-01-01

    When a preschool teacher unexpectedly found tadpoles in the school's outdoor baby pool, she recognized an unusual opportunity for her students to study pond life up close. By following the tadpoles' development, students learned about frogs, life cycles, habitats. (Contains 1 resource.)

  20. It's a Frog's Life

    ERIC Educational Resources Information Center

    Coffey, Audrey L.; Sterling, Donna R.

    2003-01-01

    When a preschool teacher unexpectedly found tadpoles in the school's outdoor baby pool, she recognized an unusual opportunity for her students to study pond life up close. By following the tadpoles' development, students learned about frogs, life cycles, habitats. (Contains 1 resource.)

  1. Cascades frog conservation assessment

    Treesearch

    Karen Pope; Catherine Brown; Marc Hayes; Gregory Green; Diane Macfarlane

    2014-01-01

    The Cascades frog (Rana cascadae) is a montane, lentic-breeding amphibian that has become rare in the southern Cascade Range and remains relatively widespread in the Klamath Mountains of northern California. In the southern Cascades, remaining populations occur primarily in meadow habitats where the fungal disease, chytridiomycosis, and habitat...

  2. Breeding Guild Determines Frog Distributions in Response to Edge Effects and Habitat Conversion in the Brazil's Atlantic Forest.

    PubMed

    Ferreira, Rodrigo B; Beard, Karen H; Crump, Martha L

    2016-01-01

    Understanding the response of species with differing life-history traits to habitat edges and habitat conversion helps predict their likelihood of persistence across changing landscape. In Brazil's Atlantic Forest, we evaluated frog richness and abundance by breeding guild at four distances from the edge of a reserve: i) 200 m inside the forest, ii) 50 m inside the forest, iii) at the forest edge, and iv) 50 m inside three different converted habitats (coffee plantation, non-native Eucalyptus plantation, and abandoned pastures, hereafter matrix types). By sampling a dry and a wet season, we recorded 622 individual frogs representing 29 species, of which three were undescribed. Breeding guild (i.e. bromeliad, leaf-litter, and water-body breeders) was the most important variable explaining frog distributions in relation to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Number of large trees (i.e. DBH > 15 cm) and bromeliads best explained frog richness and abundance across distances. Twenty species found in the interior of the forest were not found in any matrix habitat. Richness and abundance across breeding guilds were higher in the rainy season but frog distributions were similar across the four distances in the two seasons. Across matrix types, leaf-litter species primarily used Eucalyptus plantations, whereas water-body species primarily used coffee plantations. Bromeliad breeders were not found inside any matrix habitat. Our study highlights the importance of primary forest for bromeliad and leaf-litter breeders. We propose that water-body breeders use edge and matrix habitats to reach breeding habitats along the valleys. Including life-history characteristics, such as breeding guild, can improve predictions of frog distributions in

  3. Chromosome banding in amphibia. XXIII. Giant W sex chromosomes and extremely small genomes in Eleutherodactylus euphronides and Eleutherodactylus shrevei (Anura, Leptodactylidae).

    PubMed

    Schmid, M; Feichtinger, W; Steinlein, C; Rupprecht, A; Haaf, T; Kaiser, H

    2002-01-01

    Highly differentiated, heteromorphic ZZ female symbol /ZW male symbol sex chromosomes were found in the karyotypes of the neotropical leptodactylid frogs Eleutherodactylus euphronides and E. shrevei. The W chromosomes are the largest heterochromatic, female-specific chromosomes so far discovered in the class Amphibia. The analyses of the banding patterns with AT- and GC base-pair specific fluorochromes show that the constitutive heterochromatin in the giant W chromosomes consists of various categories of repetitive DNA sequences. The W chromosomes of both species are similar in size, morphology and banding patterns, whereas their Z chromosomes exhibit conspicuous differences. In the cell nuclei of female animals, the W chromosomes form very prominent chromatin bodies (W chromatin). DNA flow cytometric measurements demonstrate clear differences in the DNA content of male and female erythrocytes caused by the giant W chromosome, and also shows that these Eleutherodactylus genomes are among the smallest of all amphibian genomes. The importance of the heteromorphic ZW sex chromosomes for the study of Z-linked genes, the similarities and differences of the two karyotypes, and the significance of the exceptionally small genomes are discussed.

  4. Hibernal habitat selection by Wood Frogs (Lithobates sylvaticus) in a northern New England montane landscape

    USGS Publications Warehouse

    Groff, Luke A.; Calhoun, Aram J. K.; Loftin, Cynthia S.

    2016-01-01

    Poikilothermic species, such as amphibians, endure harsh winter conditions via freeze-tolerance or freeze-avoidance strategies. Freeze-tolerance requires a suite of complex, physiological mechanisms (e.g., cryoprotectant synthesis); however, behavioral strategies (e.g., hibernal habitat selection) may be used to regulate hibernaculum temperatures and promote overwintering survival. We investigated the hibernal ecology of the freeze-tolerant Wood Frog (Lithobates sylvaticus) in north-central Maine. Our objectives were to characterize the species hibernaculum microclimate (temperature, relative humidity), evaluate hibernal habitat selection, and describe the spatial arrangement of breeding, post-breeding, and hibernal habitats. We monitored 15 frogs during two winters (2011/12: N = 10; 2012/13: N = 5), measured hibernal habitat features at micro (2 m) and macro (10 m) spatial scales, and recorded microclimate hourly in three strata (hibernaculum, leaf litter, ambient air). We compared these data to that of 57 random locations with logistic regression models, Akaike Information Criterion, and Kolmogorov–Smirnov tests. Hibernaculum microclimate was significantly different and less variable than leaf litter, ambient air, and random location microclimate. Model averaging indicated that canopy cover (−), leaf litter depth (+), and number of logs and stumps (+; microhabitat only) were important predictors of Wood Frog hibernal habitat. These habitat features likely act to insulate hibernating frogs from extreme and variable air temperatures. For example, decreased canopy cover facilitates increased snowpack depth and earlier snowpack accumulation and melt. Altered winter temperature and precipitation patterns attributable to climate change may reduce snowpack insulation, facilitate greater temperature variation in the underlying hibernacula, and potentially compromise Wood Frog winter survival.

  5. Phylogenetic relationships linking Duttaphrynus (Amphibia: Anura: Bufonidae) species based on 12S and 16S rDNA sequences.

    PubMed

    Pratihar, Suman; Bhattacharya, Manojit; Deuti, Kaushik

    2016-07-01

    Genus Duttaphrynus (Amphibia: Anura: Bufonidae) is endemic to southwestern and southern China and throughout southern Asia. Duttaphrynus phylogeny was also under debate for many years. 12S and 16S rDNAs help us to elucidate Duttaphrynus phylogeny.

  6. Reducing Children's Littering on a Nature Trail

    ERIC Educational Resources Information Center

    LaHart, David E.; Bailey, Jon S.

    1975-01-01

    This study compared incentives and educational methods to motivate children to pick up litter and to prevent littering. Incentives did aid in getting litter picked up. One-sentence anti-litter statements, educational materials, and lectures reduced littering, but incentives did not. (MR)

  7. Reducing Children's Littering on a Nature Trail

    ERIC Educational Resources Information Center

    LaHart, David E.; Bailey, Jon S.

    1975-01-01

    This study compared incentives and educational methods to motivate children to pick up litter and to prevent littering. Incentives did aid in getting litter picked up. One-sentence anti-litter statements, educational materials, and lectures reduced littering, but incentives did not. (MR)

  8. Teams Explore the Whole Frog

    ERIC Educational Resources Information Center

    Cessna, Clair E.

    1973-01-01

    Describes the content and organization of a laboratory session in which student teams work on the organs, tissues, and parasites of a pithed frog. The procedure maximizes participation by every student, makes possible the fullest use of each frog, and permits a rather broad study in a limited time. (JR)

  9. Teams Explore the Whole Frog

    ERIC Educational Resources Information Center

    Cessna, Clair E.

    1973-01-01

    Describes the content and organization of a laboratory session in which student teams work on the organs, tissues, and parasites of a pithed frog. The procedure maximizes participation by every student, makes possible the fullest use of each frog, and permits a rather broad study in a limited time. (JR)

  10. The Effects of Litter on Littering Behavior in a Forest Environment

    ERIC Educational Resources Information Center

    Crump, S. Larry; And Others

    1977-01-01

    The effects of littered and nonlittered areas on littering behavior were determined in picnic areas in the Uinta National Forest, Utah. Littered and nonlittered conditions were controlled by spreading or removing litter from specified areas. Observations revealed that in the nonlittered areas there was more litter than in the littered areas. (CS)

  11. The Effects of Litter on Littering Behavior in a Forest Environment

    ERIC Educational Resources Information Center

    Crump, S. Larry; And Others

    1977-01-01

    The effects of littered and nonlittered areas on littering behavior were determined in picnic areas in the Uinta National Forest, Utah. Littered and nonlittered conditions were controlled by spreading or removing litter from specified areas. Observations revealed that in the nonlittered areas there was more litter than in the littered areas. (CS)

  12. Mower/Litter Removal

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Burg Corporation needed to get more power out of the suction system in their Vac 'N Bag grass mower/litter remover. The president submitted a problem statement to the Marshall Space Flight Center Technology Transfer Office, which devised a way to guide heavier items of trash to a point where suction was greatest, and made changes to the impeller and the exhaust port, based on rocket propulsion technology. The improved system is used by highway departments, city governments and park authorities, reducing work time by combining the tasks of grass cutting and vacuuming trash and grass clippings.

  13. Lithobates sylvaticus (wood frog)

    USGS Publications Warehouse

    Fuller, Pam

    2016-01-01

    A single specimen found southwest of Hattiesburg in Timberton (31.270391oN, 89.327675oW; WGS 84). 23 July 2015. Gary, Kat, and Ron Lukens. Verifi ed by Kenneth Krysko, Florida Museum of Natural History (UF-Herpetology 176455). This species has never been recorded from the state of Mississippi before (Dodd 2013. Frogs of the United States and Canada – Volume 2. John Hopkins University Press, Baltimore, Maryland. 982 pp.). According to Dodd (2013), the closest population is located in east central Alabama, approximately 400 km to the northeast, as documented by Davis and Folkerts (1986. Brimleyana 12:29-50).

  14. Landscape resistance to frog movements

    USGS Publications Warehouse

    Mazerolle, M.J.; Desrochers, A.

    2005-01-01

    An animal's capacity to recolonize a patch depends on at least two components: its ability to detect the patch and its ability to reach it. However, the disruption of such processes by anthropic disturbances could explain low animal abundance patterns observed by many investigators in certain landscapes. Through field experiments, we compared the orientation and homing success of northern green frogs (Rana clamitans melanota Rafinesque, 1820) and northern leopard frogs (Rana pipiens Schreber, 1782) translocated across disturbed or undisturbed surfaces. We also monitored the path selected by individuals when presented with a choice between a short distance over a disturbed surface and a longer, undisturbed route. Finally, we measured the water loss and behaviour of frogs on substrates resulting from anthropogenic disturbances and a control. When presented with a choice, 72% of the frogs avoided disturbed surfaces. Although able to orient towards the pond of capture when translocated on disturbed surfaces, frogs had a lower probability of homing successfully to the pond than when translocated at a similar distance on an undisturbed surface. Frogs lost the most water on substrates associated with disturbance and in the absence of cover. Our data illustrate that anthropically disturbed areas devoid of cover, such as mined peatlands and agricultural fields, disrupt the ability of frogs to reach habitat patches and are likely explanations to their reduced abundance patterns in such environments. ?? 2005 NRC Canada.

  15. The different meanings of the nomen Amphibia: a correction.

    PubMed

    Dubois, Alain

    2015-07-17

    I recently published a survey of the different meanings of the nomen Amphibia in taxonomic publications since 1758 (Dubois 2015). The 'meaning' of a nomen in zoological nomenclature depends on the system used for the allocation of nomina to taxa, and several such systems can be used (see e.g. Dubois 2006a-b). In the paper at stake, I used the 'orostensional nomenclatural system' (OONS) for class-series nomenclature. In this system, a class-series nomen-i.e., a nomen above the rank superfamily, therefore one whose taxonomic allocation is not regulated by the Code (Anonymous 1999)-applies, in a given classification, to the most inclusive class-series taxon that includes all its originally expressly included nominal genera (conucleogenera) and excludes all its originally expressly excluded nominal genera (alienogenera)-if such a taxon indeed exists in this classification. However, if one a least of the alienogenera is now part of the most inclusive taxon including all the conucleogenera, the nomen cannot be taxonomically allocated and qualifies as an anaptonym in the classification used as reference (Dubois 2006a-b, 2011), although it may not be so under another taxonomic frame.

  16. Ultrastructure of the mature spermatozoa of caecilians (Amphibia: Gymnophiona).

    PubMed

    Scheltinga, David M; Wilkinson, Mark; Jamieson, Barrie G M; Oommen, Oommen V

    2003-11-01

    The spermatozoa of Gymnophiona show the following autapomorphies: 1) penetration of the distal centriole by the axial fiber; 2) presence of an acrosomal baseplate; 3) presence of an acrosome seat (flattened apical end of nucleus); and 4) absence of juxta-axonemal fibers. The wide separation of the plasma membrane bounding the undulating membrane is here also considered to be apomorphic. Three plesiomorphic spermatozoal characters are recognized that are not seen in other Amphibia but occur in basal amniotes: 1) presence of mitochondria with a delicate array of concentric cristae (concentric cristae of salamander spermatozoa differ in lacking the delicate array); 2) presence of peripheral dense fibers associated with the triplets of the distal centriole; and 3) presence of a simple annulus (a highly modified, elongate annulus is present in salamander sperm). The presence of an endonuclear canal containing a perforatorium is a plesiomorphic feature of caecilian spermatozoa that is shared with urodeles, some basal anurans, sarcopterygian fish, and some amniotes. Spermatozoal synapomorphies are identified for 1) the Uraeotyphlidae and Ichthyophiidae, and 2) the Caeciliidae and Typhlonectidae, suggesting that the members of each pair of families are more closely related to each other than to other caecilians. Although caecilian spermatozoa exhibit the clear amphibian synapomorphy of the unilateral location of the undulating membrane and its axial fiber, they have no apomorphic characters that suggest a closer relationship to either the Urodela or Anura.

  17. Leopard frog and wood frog reproduction in Colorado and Wyoming

    USGS Publications Warehouse

    Corn, Paul Stephen; Livo, Lauren J.

    1989-01-01

    Between 1978 and 1988, we recorded reproductive information from populations of ranid frogs in Colorado and Wyoming. Egg masses from five plains and montane populations of northern leopard frogs (Rana pipiens) contained 645-6272 eggs (x̄ = 3045, N = 68 egg masses). In two montane populations of wood frogs (Rana sylvatica) numbers of eggs per egg mass varied from 711-1248 (x̄ = 876, N = 15) and probably were equal to total clutch size. Mean hatching success was 90% in egg masses from one R. sylvatica population and ranged from 70% to 99% in R. pipiens egg masses. Rana pipiens egg masses from one location were assigned to three overlapping size distributions, which we believe reflects the underlying age structure of female frogs.

  18. Habitat, food, and climate affecting leaf litter anuran assemblages in an Atlantic Forest remnant

    NASA Astrophysics Data System (ADS)

    Rievers, Camila Rabelo; Pires, Maria Rita Silvério; Eterovick, Paula Cabral

    2014-07-01

    Leaf litter anuran assemblages include both species that have terrestrial development and species that, during the breeding season, aggregate around bodies of water where their tadpoles develop. The resources used by these two groups in the leaf litter are likely to differ, as well as their sampled species richness, abundance and biomass as resource availability changes. We conducted a 12-month survey of leaf litter anuran assemblages at three forest areas in the largest Atlantic Forest remnant in the state of Minas Gerais in southeastern Brazil. Each month we estimated, based on capture rates, anuran species richness, abundance, and biomass as assemblage descriptors. We also measured variables that could potentially affect these descriptors in space and time: invertebrate litter fauna (abundance and richness of taxa), leaf litter biomass, and microclimatic conditions (air humidity, air and soil temperature, soil water content, and rainfall). We tested for differences in these variables among areas. We used general linear models to search for the variables that best explained variation in anuran abundance (based on capture rates) throughout the year. We analyzed species with terrestrial development (TD) and with aquatic larvae (AL) separately. We recorded 326 anurans of 15 species. Sampled anuran abundance (correlated to species richness and biomass) was explained by air humidity and/or invertebrate abundance for species with TD, and by soil water content or air humidity and leaf litter biomass for species with AL. The variability in the results of studies on leaf litter frogs that try to find variables to explain changes in community descriptors may be due to spatial variation of resources among areas and also to the fact that TD and AL species are frequently analyzed together, when in fact they are likely to show different responses to resources present in the leaf litter habitat, reflected on capture rates.

  19. Environmentally-friendly animal litter

    DOEpatents

    Boxley, Chett; McKelvie, Jessica

    2013-09-03

    An animal litter composition that includes geopolymerized ash particulates having a network of repeating aluminum-silicon units is described herein. Generally, the animal litter is made from a quantity of a pozzolanic ash mixed with an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. This geopolymerization reaction may occur within a pelletizer. After the geopolymerized ash is formed, it may be dried and sieved to a desired size. These geopolymerized ash particulates may be used to make a non-clumping or clumping animal litter or other absorbing material. Aluminum sulfate, clinoptilolite, silica gel, sodium alginate and mineral oil may be added as additional ingredients.

  20. Environmentally-friendly animal litter

    SciTech Connect

    Boxley, Chett; McKelvie, Jessica

    2012-08-28

    An animal litter composition including geopolymerized ash particulates having a network of repeating aluminum-silicon units is described herein. Generally, the animal litter is made from a quantity of a pozzolanic ash mixed with a sufficient quantity of water and an alkaline activator to initiate a geopolymerization reaction that forms geopolymerized ash. After the geopolymerized ash is formed, it is dried, broken into particulates, and sieved to a desired size. These geopolymerized ash particulates are used to make a non-clumping or clumping animal litter. Odor control is accomplished with the addition of a urease inhibitor, pH buffer, an odor eliminating agent, and/or fragrance.

  1. Subsurface band application of poultry litter

    USDA-ARS?s Scientific Manuscript database

    Broiler litter is commonly used as a fertilizer on pastures and cropland. Poultry litter is typically land-applied by broadcasting the litter on the soil surface. Rain falling on soil to which poultry litter has been applied, may carry phosphorus (P) and nitrogen (N) nutrients from the soil into s...

  2. A Comparison of V-Frog[C] to Physical Frog Dissection

    ERIC Educational Resources Information Center

    Lalley, James P.; Piotrowski, Phillip S.; Battaglia, Barbara; Brophy, Keith; Chugh, Kevin

    2010-01-01

    The purpose of the present study was to examine and compare the effectiveness of virtual frog dissection using V-Frog[C] and physical frog dissection on learning, retention, and affect. Subjects were secondary students enrolled in year-long life science classes in a suburban high school (N=102). Virtual dissections were done with V-Frog[C], a…

  3. To Be or Not to Be...a Frog: The Frog Prince and Shifting Paradigms.

    ERIC Educational Resources Information Center

    Crane, Lisa Marie

    1997-01-01

    Discusses three modern variations of the classic "Frog Prince" folk tale: "Pondlarker" (Fred Gwynne); "The Frog Prince Continued" (Jon Scieszka); and "The Prince of the Pond" (Donna Jo Napoli). Notes that these variants create a world in which frogs can have values, wisdom, and emotion, and in which frogs can influence the ways of humanity. (RS)

  4. To Be or Not to Be...a Frog: The Frog Prince and Shifting Paradigms.

    ERIC Educational Resources Information Center

    Crane, Lisa Marie

    1997-01-01

    Discusses three modern variations of the classic "Frog Prince" folk tale: "Pondlarker" (Fred Gwynne); "The Frog Prince Continued" (Jon Scieszka); and "The Prince of the Pond" (Donna Jo Napoli). Notes that these variants create a world in which frogs can have values, wisdom, and emotion, and in which frogs can influence the ways of humanity. (RS)

  5. The Classroom Animal: The Leopard Frog.

    ERIC Educational Resources Information Center

    Science and Children, 1985

    1985-01-01

    Describes the natural history of the leopard frog and factors which make it appropriate for short-term study in the classroom. Information on the frog's habits, life cycle, housing, care, and health is included. (DH)

  6. [Helminth fauna of amphibians (Vertebrata: Amphibia) in the Republic of Belarus].

    PubMed

    Shimalov, V V

    2009-01-01

    Historical review of the investigations of helminth fauna in amphibians from Belarus is presented. In 12 amphibian species examined by different authors 46 helminth species were found, including 29 Trematoda, 13 Nematoda, 1 Monogenea, 2 Cestoda, and 1 Acanthocephala. Original data on helminths parasitizing Amphibia in Byelorussian Polesie, by the results of long-term investigations in 1986-2004 are given. Distribution of 40 helminth species by hosts and respective infestation rates are reported.

  7. Species-specificity of amphibia carbohydrate chains: the Bufo viridis case study.

    PubMed

    Coppin, Alexandra; Maes, Emmanuel; Strecker, Gérard

    2002-02-05

    The jelly coat surrounding the eggs of amphibia is composed of oviducal mucins and plays an important role in the fertilization process. From a structural and chemical point of view, these jellies are very different from one species to another. Bufo viridis is the 13th amphibia species studied in term of carbohydrate structural analysis. The oligosaccharides have been released from the oviducal mucins by reductive beta elimination, purified by various chromatography procedures and analyzed by (1)H and (13)C 1D-2D NMR spectroscopy. Among the 15 compounds, ten have novel structures, although they possess some well-known structural patterns as blood group epitopes (Le(x), Le(y)) or other sequences already observed in other amphibia species. These results reinforce our hypothesis about the strict species-specificity of these carbohydrate chains. It must be noted that such species-specificity does not depend on one particular monosaccharide but it is rather due to a set of particular tri- or tetrasaccharide sequences. Hence, B. viridis species could be characterized by the simultaneous presence of a 2,3,6-trisubstituted galactosyl residue, the GlcNAc(beta 1-3)[Fuc(alpha 1-4)]GlcNAc beta sequence and the Le(x), Le(y) or Cad determinants. The anionic charge of the oligosaccharides is carried only by sialic acid alpha-(2-->6)-linked to GalNAc-ol residue as in Bufo bufo or in Bufo arenarum.

  8. What's the Difference between Frogs and Toads?

    ERIC Educational Resources Information Center

    Brown, Herrick

    2004-01-01

    The difference between frogs and toads can be determined scientifically but is based in the historic use of the terms frog and toad. These are Old English words for the common frog, "Rana temporaria," and the common toad, "Bufo bufo," both inhabitants of the British Isles. In the process of describing a new anuran species,…

  9. 49 CFR 213.137 - Frogs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Frogs. 213.137 Section 213.137 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.137 Frogs. (a) The flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 13/8 inches, or...

  10. 49 CFR 213.137 - Frogs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Frogs. 213.137 Section 213.137 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.137 Frogs. (a) The flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 13/8 inches, or...

  11. 49 CFR 213.137 - Frogs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Frogs. 213.137 Section 213.137 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.137 Frogs. (a) The flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 13/8 inches, or...

  12. 49 CFR 213.137 - Frogs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Frogs. 213.137 Section 213.137 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.137 Frogs. (a) The flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 13/8 inches, or...

  13. What's the Difference between Frogs and Toads?

    ERIC Educational Resources Information Center

    Brown, Herrick

    2004-01-01

    The difference between frogs and toads can be determined scientifically but is based in the historic use of the terms frog and toad. These are Old English words for the common frog, "Rana temporaria," and the common toad, "Bufo bufo," both inhabitants of the British Isles. In the process of describing a new anuran species,…

  14. 49 CFR 213.137 - Frogs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Frogs. 213.137 Section 213.137 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.137 Frogs. (a) The flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 13/8 inches, or...

  15. Litter chemistry prevails over litter consumers in mediating effects of past steel industry activities on leaf litter decomposition.

    PubMed

    Lucisine, Pierre; Lecerf, Antoine; Danger, Michaël; Felten, Vincent; Aran, Delphine; Auclerc, Apolline; Gross, Elisabeth M; Huot, Hermine; Morel, Jean-Louis; Muller, Serge; Nahmani, Johanne; Maunoury-Danger, Florence

    2015-12-15

    Soil pollution has adverse effects on the performance and life history traits of microorganisms, plants, and animals, yet evidence indicates that even the most polluted sites can support structurally-complex and dynamic ecosystems. The present study aims at determining whether and how litter decomposition, one of the most important soil ecological processes leaf, is affected in a highly trace-metal polluted site. We postulated that past steel mill activities resulting in soil pollution and associated changes in soil characteristics would influence the rate of litter decomposition through two non-exclusive pathways: altered litter chemistry and responses of decomposers to lethal and sub-lethal toxic stress. We carried out a litter-bag experiment using Populus tremula L. leaf litter collected at, and allowed to decompose in, a trace metal polluted site and in three unpolluted sites used as controls. We designed a fully-factorial transplant experimental design to assess effects of litter origin and exposure site on the rate of litter decomposition. We further determined initial litter chemistry, fungal biomass, mesofauna abundance in litter bags, and the soil macrofauna community. Irrespective of the site of litter exposure, litter originating from the polluted site had a two-fold faster decomposition than litter from the unpolluted sites. Litter chemistry, notably the lignin content, seemed most important in explaining the degradation rate of the leaf litter. Abundance of meso and macro-detritivores was higher at the polluted site than at the unpolluted sites. However, litter decomposition proceeded at similar rates in polluted and unpolluted sites. Our results show that trace metal pollution and associated soil and litter changes do not necessarily weaken consumer control on litter decomposition through lethal and sub-lethal toxic stress.

  16. FROG: Time-series analysis

    NASA Astrophysics Data System (ADS)

    Allan, Alasdair

    2014-06-01

    FROG performs time series analysis and display. It provides a simple user interface for astronomers wanting to do time-domain astrophysics but still offers the powerful features found in packages such as PERIOD (ascl:1406.005). FROG includes a number of tools for manipulation of time series. Among other things, the user can combine individual time series, detrend series (multiple methods) and perform basic arithmetic functions. The data can also be exported directly into the TOPCAT (ascl:1101.010) application for further manipulation if needed.

  17. Breeding Guild Determines Frog Distributions in Response to Edge Effects and Habitat Conversion in the Brazil’s Atlantic Forest

    PubMed Central

    Ferreira, Rodrigo B.; Beard, Karen H.; Crump, Martha L.

    2016-01-01

    Understanding the response of species with differing life-history traits to habitat edges and habitat conversion helps predict their likelihood of persistence across changing landscape. In Brazil’s Atlantic Forest, we evaluated frog richness and abundance by breeding guild at four distances from the edge of a reserve: i) 200 m inside the forest, ii) 50 m inside the forest, iii) at the forest edge, and iv) 50 m inside three different converted habitats (coffee plantation, non-native Eucalyptus plantation, and abandoned pastures, hereafter matrix types). By sampling a dry and a wet season, we recorded 622 individual frogs representing 29 species, of which three were undescribed. Breeding guild (i.e. bromeliad, leaf-litter, and water-body breeders) was the most important variable explaining frog distributions in relation to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Number of large trees (i.e. DBH > 15 cm) and bromeliads best explained frog richness and abundance across distances. Twenty species found in the interior of the forest were not found in any matrix habitat. Richness and abundance across breeding guilds were higher in the rainy season but frog distributions were similar across the four distances in the two seasons. Across matrix types, leaf-litter species primarily used Eucalyptus plantations, whereas water-body species primarily used coffee plantations. Bromeliad breeders were not found inside any matrix habitat. Our study highlights the importance of primary forest for bromeliad and leaf-litter breeders. We propose that water-body breeders use edge and matrix habitats to reach breeding habitats along the valleys. Including life-history characteristics, such as breeding guild, can improve predictions of frog distributions in

  18. Mercury bioaccumulation in wood frogs developing in seasonal pools

    USGS Publications Warehouse

    Loftin, Cynthia S.; Calhoun, Aram J. K.; Nelson, Sarah J.; Elskus, Adria; Simon, Kevin S.

    2012-01-01

    Seasonal woodland pools contribute significant biomass to terrestrial ecosystems through production of pool-breeding amphibians. The movement of amphibian metamorphs potentially transports toxins bioaccumulated during larval development in the natal pool into the surrounding terrestrial environment. We documented total mercury (THg) in seasonal woodland pool water, sediment, litter, and Lithobates sylvaticus LeConte (Wood Frog) in Acadia National Park, ME. THg concentrations in pool water varied over the study season, increasing during April—June and remaining high in 2 of 4 pools upon October refill. Water in pools surrounded by softwoods had lower pH, greater dissolved organic carbon, and greater THg concentrations than pools surrounded by hardwoods, with seasonal patterns in sediment THg but not litter THg. THg increased rapidly from near or below detection in 1–2 week old embryos (<0.2 ng; 0–0.49 ppb wet weight) to 17.1–54.2 ppb in tadpoles within 6 weeks; 7.2–42.0% of THg was methyl Hg in tadpoles near metamorphosis. Metamorphs emigrating from seasonal pools may transfer mercury into terrestrial food webs.

  19. FROG - Fingerprinting Genomic Variation Ontology.

    PubMed

    Abinaya, E; Narang, Pankaj; Bhardwaj, Anshu

    2015-01-01

    Genetic variations play a crucial role in differential phenotypic outcomes. Given the complexity in establishing this correlation and the enormous data available today, it is imperative to design machine-readable, efficient methods to store, label, search and analyze this data. A semantic approach, FROG: "FingeRprinting Ontology of Genomic variations" is implemented to label variation data, based on its location, function and interactions. FROG has six levels to describe the variation annotation, namely, chromosome, DNA, RNA, protein, variations and interactions. Each level is a conceptual aggregation of logically connected attributes each of which comprises of various properties for the variant. For example, in chromosome level, one of the attributes is location of variation and which has two properties, allosomes or autosomes. Another attribute is variation kind which has four properties, namely, indel, deletion, insertion, substitution. Likewise, there are 48 attributes and 278 properties to capture the variation annotation across six levels. Each property is then assigned a bit score which in turn leads to generation of a binary fingerprint based on the combination of these properties (mostly taken from existing variation ontologies). FROG is a novel and unique method designed for the purpose of labeling the entire variation data generated till date for efficient storage, search and analysis. A web-based platform is designed as a test case for users to navigate sample datasets and generate fingerprints. The platform is available at http://ab-openlab.csir.res.in/frog.

  20. FROG - Fingerprinting Genomic Variation Ontology

    PubMed Central

    Bhardwaj, Anshu

    2015-01-01

    Genetic variations play a crucial role in differential phenotypic outcomes. Given the complexity in establishing this correlation and the enormous data available today, it is imperative to design machine-readable, efficient methods to store, label, search and analyze this data. A semantic approach, FROG: “FingeRprinting Ontology of Genomic variations” is implemented to label variation data, based on its location, function and interactions. FROG has six levels to describe the variation annotation, namely, chromosome, DNA, RNA, protein, variations and interactions. Each level is a conceptual aggregation of logically connected attributes each of which comprises of various properties for the variant. For example, in chromosome level, one of the attributes is location of variation and which has two properties, allosomes or autosomes. Another attribute is variation kind which has four properties, namely, indel, deletion, insertion, substitution. Likewise, there are 48 attributes and 278 properties to capture the variation annotation across six levels. Each property is then assigned a bit score which in turn leads to generation of a binary fingerprint based on the combination of these properties (mostly taken from existing variation ontologies). FROG is a novel and unique method designed for the purpose of labeling the entire variation data generated till date for efficient storage, search and analysis. A web-based platform is designed as a test case for users to navigate sample datasets and generate fingerprints. The platform is available at http://ab-openlab.csir.res.in/frog. PMID:26244889

  1. FROGS (Friends of Granites) report

    NASA Astrophysics Data System (ADS)

    Miller, Calvin

    This VGP News, which is devoted to petrology, is a good one for noting the existence of FROGS. FROGS is, as the name suggests, an informal organization of people whose research relates in one way or another to granitic rocks. Its purpose has been to promote communication among geoscientists with different perspectives and concerns about felsic plutonism. Initially, a major focus was experimental petrology and integration of field-oriented and lab-oriented viewpoints; now that there is the opportunity to communicate with the Eos readership, an obvious additional goal will be to bring together volcanic and plutonic views of felsic magmatism.FROGS first gathered in late 1982 under the guidance of E-an Zen and Pete Toulmin (both at U.S. Geological Survey (USGS), Reston, Va.), who saw a need for greater interaction among those interested in granites and for renewed, focused experimental investigations. They produced two newsletters (which were sent out by direct mail) and organized an informal meeting at the Geological Society of America meeting at Indianapolis, Ind., and then turned over the FROG reins to Sue Kieffer (USGS, Flagstaff, Ariz.) and John Clemens (Arizona State University, Tempe). They generated another newsletter, which was directly mailed to a readership that had grown beyond 200.

  2. Poultry Industry Trends for Litter Utilization

    USDA-ARS?s Scientific Manuscript database

    Broiler litter utilization falls primarily into two broad categories, as fertilizer or in litter-to-energy processes. Without economic, environmentally sound litter uses, potential or real regional litigation may force alternative management that can be detrimental to the grower’s bottom line as wel...

  3. Methods for estimating litter decomposition. Chapter 8

    Treesearch

    Noah J. Karberg; Neal A. Scott; Christian P. Giardina

    2008-01-01

    Litterfall in terrestrial ecosystems represents the primary pathway for nutrient return to soil. Heterotrophic metabolism, facilitated through comminution by small insects and leaching during precipitation events, results in the release of plant litter carbon as CO2 into the atmosphere. The balance between litter inputs and heterotrophic litter...

  4. 46 CFR 108.709 - Litter.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Litter. 108.709 Section 108.709 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Miscellaneous Equipment § 108.709 Litter. Each unit must have a litter that is— (a) Stowed in a location that...

  5. 46 CFR 108.709 - Litter.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Litter. 108.709 Section 108.709 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Miscellaneous Equipment § 108.709 Litter. Each unit must have a litter that is— (a) Stowed in a location that...

  6. Care and Feeding of Frogs

    NASA Astrophysics Data System (ADS)

    Pan, Margaret; Chiang, Eugene

    2012-01-01

    "Propellers" are features in Saturn's A ring associated with moonlets that open partial gaps. They exhibit non-Keplerian motion (Tiscareno et al.) the longitude residuals of the best-observed propeller, "Blériot," appear consistent with a sinusoid of period ~4 years. Pan & Chiang proposed that propeller moonlets librate in "frog resonances" with co-orbiting ring material. By analogy with the restricted three-body problem, they treated the co-orbital material as stationary in the rotating frame and neglected non-co-orbital material. Here we use simple numerical experiments to extend the frog model, including feedback due to the gap's motion, and drag associated with the Lindblad disk torques that cause Type I migration. Because the moonlet creates the gap, we expect the gap centroid to track the moonlet, but only after a time delay t delay, the time for a ring particle to travel from conjunction with the moonlet to the end of the gap. We find that frog librations can persist only if t delay exceeds the frog libration period P lib, and if damping from Lindblad torques balances driving from co-orbital torques. If t delay Lt P lib, then the libration amplitude damps to zero. In the case of Blériot, the frog resonance model can reproduce the observed libration period P lib ~= 4 yr. However, our simple feedback prescription suggests that Blériot's t delay ~ 0.01P lib, which is inconsistent with the observed libration amplitude of 260 km. We urge more accurate treatments of feedback to test the assumptions of our toy models.

  7. CARE AND FEEDING OF FROGS

    SciTech Connect

    Pan, Margaret; Chiang, Eugene

    2012-01-15

    'Propellers' are features in Saturn's A ring associated with moonlets that open partial gaps. They exhibit non-Keplerian motion (Tiscareno et al.); the longitude residuals of the best-observed propeller, 'Bleriot', appear consistent with a sinusoid of period {approx}4 years. Pan and Chiang proposed that propeller moonlets librate in 'frog resonances' with co-orbiting ring material. By analogy with the restricted three-body problem, they treated the co-orbital material as stationary in the rotating frame and neglected non-co-orbital material. Here we use simple numerical experiments to extend the frog model, including feedback due to the gap's motion, and drag associated with the Lindblad disk torques that cause Type I migration. Because the moonlet creates the gap, we expect the gap centroid to track the moonlet, but only after a time delay t{sub delay}, the time for a ring particle to travel from conjunction with the moonlet to the end of the gap. We find that frog librations can persist only if t{sub delay} exceeds the frog libration period P{sub lib}, and if damping from Lindblad torques balances driving from co-orbital torques. If t{sub delay} << Pl{sub ib}, then the libration amplitude damps to zero. In the case of Bleriot, the frog resonance model can reproduce the observed libration period P{sub lib} {approx_equal} 4 yr. However, our simple feedback prescription suggests that Bleriot's t{sub delay} {approx} 0.01P{sub lib}, which is inconsistent with the observed libration amplitude of 260 km. We urge more accurate treatments of feedback to test the assumptions of our toy models.

  8. Development of the pseudothumb in frogs.

    PubMed

    Tokita, Masayoshi; Iwai, Noriko

    2010-08-23

    Frogs have highly conserved hand and foot morphology, possessing four fingers and five toes. As an exception, two Japanese ranid frog species, the Otton frog Babina subaspera and the dagger frog Babina holsti, possess a unique thumb-like structure (the pseudothumb) in the forelimb, giving an appearance of a total of five fingers on the hand. To obtain insights into the developmental mechanisms that generate this novel character, we investigated the hand morphogenesis of the Otton frog. The unique morphological pattern of the pseudothumb was already established in juveniles. Surprisingly, the bud-like structure, which is similar to the area of inductive activity (e.g. feather buds in birds and the carapacial ridge in turtles), was detected over the site where the future prepollex develops in larvae. By contrast, this bud-like structure was not found in larvae of other ranid species. We discuss possible scenarios that would favour the evolution of this very unusual trait in frogs.

  9. A Depolarizing Electrogenic Pump in Frog Muscle

    DTIC Science & Technology

    1975-08-01

    mw copy AFRRI SR75-20 AUGUST 1975 AFRRI SCIENTIFIC REPORT O ■ to A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. Geduldig D. R...Academy of Sciences - National Research Council. AFRRI SR75-20 August 1975 A DEPOLARIZING ELECTROGENIC PUMP IN FROG MUSCLE D. GEDULDIG* D. R...INTRODUCTION When Na-enriched frog muscles are bathed in Na- and K-free saline, the small amount of potassium which could accumulate outside of the membrane

  10. HARDENING FROG POINTS BY EXPLOSIVE ENERGY,

    DTIC Science & Technology

    Experiments were made to determine the most efficient method of strain hardening railroad frog points in order to increase their fatigue resistance...Mechanical strain hardening with rolls 40 mm in diameter under a load of 8 tons produced in standard frogs cast from G13L high-manganese steel (AISI...Hadfield steel) a work-hardened surface layer 3-5 mm thick with a hardness of 340 HB. In other experiments, the frogs were hardened by exploding a

  11. Cosmocercoides himalayanus sp. nov. (Nematoda, Cosmocercidae) in Duttaphrynus himalayanus (Amphibia, Anura) from Dehradun (Uttarakhand), India.

    PubMed

    Rizvi, Anjum N; Bursey, Charles R

    2014-03-01

    Cosmocercoides himalayanus sp. nov. (Nematoda, Cosmocercidae) from the large intestine of Duttaphrynus himalayanus (Amphibia, Anura) from Dehradun, India is described and illustrated. Cosmocercoides himalayanus sp. nov. represents the 21st species assigned to the genus and the 9th species from the Oriental biogeographical region. Cosmocercoides himalayanus sp. nov. differs from the previously described Oriental species in number and position of rosette papillae; it is the only species possessing 24 or more rosette papillae to have 4 postcloacal papillae. In addition, a list of species assigned to Cosmocercoides is provided; however, C. fotedari Arya, 1992 is removed from the genus and until further study is considered a species inquirenda.

  12. Reflections on a systematic nomenclature for antimicrobial peptides from the skins of frogs of the family Ranidae.

    PubMed

    Conlon, J Michael

    2008-10-01

    Frogs belonging to the extensive family Ranidae represent a valuable source of antimicrobial peptides with therapeutic potential but there is currently no consistent system of nomenclature to describe these peptides. Terminology based solely on species name does not reflect the evolutionary relationships existing between peptides encoded by orthologous and paralogous genes. On the basis of limited structural similarity, at least 14 well-established peptide families have been identified (brevinin-1, brevinin-2, esculentin-1, esculentin-2, japonicin-1, japonicin-2, nigrocin-2, palustrin-1, palustrin-2, ranacyclin, ranalexin, ranatuerin-1, ranatuerin-2, temporin). It is proposed that terms that are synonymous with these names should no longer be used. Orthologous peptides from different species may be characterized by the initial letter of that species, set in upper case, with paralogs belonging to the same peptide family being assigned letters set in lower case, e.g. brevinin-1Pa, brevinin-1Pb, etc. When two species begin with the same initial letter, two letters may be used, e.g. P for pipiens and PL for palustris. Species names and assignments to genera may be obtained from Amphibian Species of the World Electronic Database, accessible at http://research.amnh.org/herpetology/amphibia/index.php. American Museum of Natural History, New York, USA.

  13. The husbandry and care of dendrobatid frogs.

    PubMed

    St Claire, Mark B; Kennett, Mary J; Thomas, Marvin L; Daly, John W

    2005-11-01

    Dendrobatid frogs are studied primarily for the bioactive alkaloids found in their skin. Also known as poison-dart frogs, these animals accumulate toxic alkaloids from dietary sources. The function and uses of the many alkaloids, the alkaloid accumulation system, and the basic biology and physiology of the frogs themselves are of research interest. Here we overview the taxonomy of these frogs and some of the unique aspects of their natural biology and reproduction. We also describe the components of a successful laboratory housing system, including temperature, lighting, humidity, ventilation, nutrition, health considerations, and handling. A brief summary of dendrobatid research highlights is provided.

  14. Climate and litter quality differently modulate the effects of soil fauna on litter decomposition across biomes.

    PubMed

    García-Palacios, Pablo; Maestre, Fernando T; Kattge, Jens; Wall, Diana H

    2013-08-01

    Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesised litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~ 37%). [corrected]. However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. © 2013 John Wiley & Sons Ltd/CNRS.

  15. Climate and litter quality differently modulate the effects of soil fauna on litter decomposition across biomes

    PubMed Central

    García-Palacios, Pablo; Maestre, Fernando T.; Kattge, Jens; Wall, Diana H.

    2015-01-01

    Climate and litter quality have been identified as major drivers of litter decomposition at large spatial scales. However, the role played by soil fauna remains largely unknown, despite its importance for litter fragmentation and microbial activity. We synthesized litterbag studies to quantify the effect sizes of soil fauna on litter decomposition rates at the global and biome scales, and to assess how climate, litter quality and soil fauna interact to determine such rates. Soil fauna consistently enhanced litter decomposition at both global and biome scales (average increment ~27%). However, climate and litter quality differently modulated the effects of soil fauna on decomposition rates between biomes, from climate-driven biomes to those where climate effects were mediated by changes in litter quality. Our results advocate for the inclusion of biome-specific soil fauna effects on litter decomposition as a mean to reduce the unexplained variation in large-scale decomposition models. PMID:23763716

  16. Naturally occurring fluorescence in frogs

    PubMed Central

    Taboada, Carlos; Brunetti, Andrés E.; Pedron, Federico N.; Carnevale Neto, Fausto; Estrin, Darío A.; Bari, Sara E.; Chemes, Lucía B.; Peporine Lopes, Norberto; Lagorio, María G.

    2017-01-01

    Fluorescence, the absorption of short-wavelength electromagnetic radiation reemitted at longer wavelengths, has been suggested to play several biological roles in metazoans. This phenomenon is uncommon in tetrapods, being restricted mostly to parrots and marine turtles. We report fluorescence in amphibians, in the tree frog Hypsiboas punctatus, showing that fluorescence in living frogs is produced by a combination of lymph and glandular emission, with pigmentary cell filtering in the skin. The chemical origin of fluorescence was traced to a class of fluorescent compounds derived from dihydroisoquinolinone, here named hyloins. We show that fluorescence contributes 18−29% of the total emerging light under twilight and nocturnal scenarios, largely enhancing brightness of the individuals and matching the sensitivity of night vision in amphibians. These results introduce an unprecedented source of pigmentation in amphibians and highlight the potential relevance of fluorescence in visual perception in terrestrial environments. PMID:28289227

  17. Naturally occurring fluorescence in frogs.

    PubMed

    Taboada, Carlos; Brunetti, Andrés E; Pedron, Federico N; Carnevale Neto, Fausto; Estrin, Darío A; Bari, Sara E; Chemes, Lucía B; Peporine Lopes, Norberto; Lagorio, María G; Faivovich, Julián

    2017-04-04

    Fluorescence, the absorption of short-wavelength electromagnetic radiation reemitted at longer wavelengths, has been suggested to play several biological roles in metazoans. This phenomenon is uncommon in tetrapods, being restricted mostly to parrots and marine turtles. We report fluorescence in amphibians, in the tree frog Hypsiboas punctatus, showing that fluorescence in living frogs is produced by a combination of lymph and glandular emission, with pigmentary cell filtering in the skin. The chemical origin of fluorescence was traced to a class of fluorescent compounds derived from dihydroisoquinolinone, here named hyloins. We show that fluorescence contributes 18-29% of the total emerging light under twilight and nocturnal scenarios, largely enhancing brightness of the individuals and matching the sensitivity of night vision in amphibians. These results introduce an unprecedented source of pigmentation in amphibians and highlight the potential relevance of fluorescence in visual perception in terrestrial environments.

  18. Measurement of broiler litter production rates and nutrient content using recycled litter.

    PubMed

    Coufal, C D; Chavez, C; Niemeyer, P R; Carey, J B

    2006-03-01

    It is important for broiler producers to know litter production rates and litter nutrient content when developing nutrient management plans. Estimation of broiler litter production varies widely in the literature due to factors such as geographical region, type of housing, size of broiler produced, and number of flocks reared on the same litter. Published data for N, P, and K content are also highly variable. In addition, few data are available regarding the rate of production, characteristics, and nutrient content of caked litter (cake). In this study, 18 consecutive flocks of broilers were reared on the same litter in experimental pens under simulated commercial conditions. The mass of litter and cake produced was measured after each flock. Samples of all litter materials were analyzed for pH, moisture, N, P, and K. Average litter and cake moisture content were 26.4 and 46.9%, respectively. Significant variation in litter and cake nutrient content was observed and can largely be attributed to ambient temperature differences. Average litter, cake, and total litter (litter plus cake) production rates were 153.3, 74.8, and 228.2 g of dry litter material per kg of live broiler weight (g/kg) per flock, respectively. Significant variation in litter production rates among flocks was also observed. Cumulative litter, cake, and total litter production rates after 18 flocks were 170.3, 78.7, and 249.0 g/kg, respectively. The data produced from this research can be used by broiler producers to estimate broiler litter and cake production and the nutrient content of these materials.

  19. Marine litter prediction by artificial intelligence.

    PubMed

    Balas, Can Elmar; Ergin, Aysen; Williams, Allan T; Koc, Levent

    2004-03-01

    Artificial intelligence techniques of neural network and fuzzy systems were applied as alternative methods to determine beach litter grading, based on litter surveys of the Antalya coastline (the Turkish Riviera). Litter measurements were categorized and assessed by artificial intelligence techniques, which lead to a new litter categorization system. The constructed neural network satisfactorily predicted the grading of the Antalya beaches and litter categories based on the number of litter items in the general litter category. It has been concluded that, neural networks could be used for high-speed predictions of litter items and beach grading, when the characteristics of the main litter category was determined by field studies. This can save on field effort when fast and reliable estimations of litter categories are required for management or research studies of beaches--especially those concerned with health and safety, and it has economic implications. The main advantages in using fuzzy systems are that they consider linguistic adjectival definitions, e.g. many/few, etc. As a result, additional information inherent in linguistic comments/refinements and judgments made during field studies can be incorporated in grading systems.

  20. Riparian plant litter quality increases with latitude.

    PubMed

    Boyero, Luz; Graça, Manuel A S; Tonin, Alan M; Pérez, Javier; J Swafford, Andrew; Ferreira, Verónica; Landeira-Dabarca, Andrea; A Alexandrou, Markos; Gessner, Mark O; McKie, Brendan G; Albariño, Ricardo J; Barmuta, Leon A; Callisto, Marcos; Chará, Julián; Chauvet, Eric; Colón-Gaud, Checo; Dudgeon, David; Encalada, Andrea C; Figueroa, Ricardo; Flecker, Alexander S; Fleituch, Tadeusz; Frainer, André; Gonçalves, José F; Helson, Julie E; Iwata, Tomoya; Mathooko, Jude; M'Erimba, Charles; Pringle, Catherine M; Ramírez, Alonso; Swan, Christopher M; Yule, Catherine M; Pearson, Richard G

    2017-09-05

    Plant litter represents a major basal resource in streams, where its decomposition is partly regulated by litter traits. Litter-trait variation may determine the latitudinal gradient in decomposition in streams, which is mainly microbial in the tropics and detritivore-mediated at high latitudes. However, this hypothesis remains untested, as we lack information on large-scale trait variation for riparian litter. Variation cannot easily be inferred from existing leaf-trait databases, since nutrient resorption can cause traits of litter and green leaves to diverge. Here we present the first global-scale assessment of riparian litter quality by determining latitudinal variation (spanning 107°) in litter traits (nutrient concentrations; physical and chemical defences) of 151 species from 24 regions and their relationships with environmental factors and phylogeny. We hypothesized that litter quality would increase with latitude (despite variation within regions) and traits would be correlated to produce 'syndromes' resulting from phylogeny and environmental variation. We found lower litter quality and higher nitrogen:phosphorus ratios in the tropics. Traits were linked but showed no phylogenetic signal, suggesting that syndromes were environmentally determined. Poorer litter quality and greater phosphorus limitation towards the equator may restrict detritivore-mediated decomposition, contributing to the predominance of microbial decomposers in tropical streams.

  1. Responses of litter invertebrate communities to litter manipulation in a Japanese conifer plantation

    NASA Astrophysics Data System (ADS)

    Yoshida, Tomohiro; Takito, Yuki; Soga, Masashi; Hijii, Naoki

    2013-08-01

    We examined how the litter invertebrate communities were affected by the temporal changes in the mass and structural complexity of the litter resources by adding and removing litter on the forest floor of a temperate conifer plantation (Cryptomeria japonica) in Japan. We showed that litter mass and depth in the litter-addition (L+) plots changed rapidly into a steady-state condition similar to those in the control plots, mainly due to accelerated decomposition processes during the rainy season. Higher area-based densities of litter invertebrates in the L+ plots, similar mass-based densities between the L+ and control plots, and significant positive correlations between litter mass and the number of individuals implied that the abundance of litter invertebrates would be governed by litter mass rather than by the litter depth. Many litter invertebrates including detritivores were collected even in the litter-removal (L-) area. The relative abundances of invertebrate predators collecting pitfall traps were higher in the L- plots and lower in the L+ plots compared to those in the control plots, whereas those collecting Tullgren funnels were higher in the L+ plots than in the control plots. In the L+ plots, the range of variation in the community compositions among the samples decreased significantly over time in response to a drastic decrease in litter mass, in contrast to the control plots, which showed a relatively constant community composition during the study period. Our litter manipulation experiment reveals some of the mechanisms responsible for maintaining an equilibrium state of forest-floor litter mass and for the responses of litter invertebrate communities to temporal changes in the litter.

  2. Association between litterers' profile and littering behavior: A chi-square approach

    NASA Astrophysics Data System (ADS)

    Asmui, Mas'udah; Zaki, Suhanom Mohd; Wahid, Sharifah Norhuda Syed; Mokhtar, Noorsuraya Mohd; Harith, Siti Suhaila

    2017-05-01

    Littering is not a novelty, yet a prolonged issue. The solutions have been discussed for a long time; however this issue still remains unresolved. Littering is commonly associated with littering behavior and awareness. The littering behavior is normally influenced by the litter profile such as gender, family income, education level and age. Jengka Street market, which is located in Pahang, is popularly known as a trade market. It offers diversities of wet and dry goods and is awaited by local residents and tourists. This study analyzes association between litterers' profile and littering behavior. Littering behavior is measured based on factors of trash bin facilities, awareness campaign and public littering behavior. 114 respondents were involved in this study with 62 (54.39%) are female aged more than 18 years old and majority of these female respondents are diploma holders. In addition, 78.95% of the respondents have family income below than RM3,000.00 per month. Based on the data analysis, it was found that first-time visitors littered higher than frequent visitors, lack of providing trash bin facilities contributes to positive littering behavior and there is a significant association between litterers' age and littering behavior by using chi-square approach.

  3. Postglacial Colonization of the Qinling Mountains: Phylogeography of the Swelled Vent Frog (Feirana quadranus)

    PubMed Central

    Wang, Bin; Jiang, Jianping; Xie, Feng; Li, Cheng

    2012-01-01

    Background The influence of Pleistocene climatic fluctuations on intraspecific diversification in the Qinling–Daba Mountains of East Asia remains poorly investigated. We tested hypotheses concerning refugia during the last glacial maximum (LGM) in this region by examining the phylogeography of the swelled vent frog (Feirana quadranus; Dicroglossidae, Anura, Amphibia). Methodology/Principal Findings We obtained complete mitochondrial ND2 gene sequences of 224 individuals from 34 populations of Feirana quadranus for phylogeographic analyses. Additionally, we obtained nuclear tyrosinase gene sequences of 68 F. quadranus, one F. kangxianensis and three F. taihangnica samples to test for mitochondrial introgression among them. Phylogenetic analyses based on all genes revealed no introgression among them. Phylogenetic analyses based on ND2 datasets revealed that F. quadranus was comprised of six lineages which were separated by deep valleys; the sole exception is that the Main Qinling and Micang–Western Qinling lineages overlap in distribution. Analyses of population structure indicated restricted gene flow among lineages. Coalescent simulations and divergence dating indicated that the basal diversification within F. quadranus may be associated with the dramatic uplifts of the Tibetan Plateau during the Pliocene. Coalescent simulations indicated that Wuling, Daba, and Western Qinling–Micang–Longmen Mountains were refugia for F. quadranus during the LGM. Demographic analyses indicated that the Daba lineage experienced population size increase prior to the LGM but the Main Qinling and the Micang–Western Qinling lineages expanded in population size and range after the LGM, and the other lineages almost have stable population size or slight slow population size decline. Conclusions/Significance The Qinling–Daba Mountains hosted three refugia for F. quadranus during the LGM. Populations that originated in the Daba Mountains colonized the Main Qinling Mountains

  4. A comparative analysis of frog early development

    PubMed Central

    del Pino, Eugenia M.; Venegas-Ferrín, Michael; Romero-Carvajal, Andrés; Montenegro-Larrea, Paola; Sáenz-Ponce, Natalia; Moya, Iván M.; Alarcón, Ingrid; Sudou, Norihiro; Yamamoto, Shinji; Taira, Masanori

    2007-01-01

    The current understanding of Xenopus laevis development provides a comparative background for the analysis of frog developmental modes. Our analysis of development in various frogs reveals that the mode of gastrulation is associated with developmental rate and is unrelated to egg size. In the gastrula of the rapidly developing embryos of the foam-nesting frogs Engystomops coloradorum and Engystomops randi, archenteron and notochord elongation overlapped with involution at the blastopore lip, as in X. laevis embryos. In embryos of dendrobatid frogs and in the frog without tadpoles Eleutherodactylus coqui, which develop somewhat more slowly than X. laevis, involution and archenteron elongation concomitantly occurred during gastrulation; whereas elongation of the notochord and, therefore, dorsal convergence and extension, occurred in the postgastrula. In contrast, in the slow developing embryos of the marsupial frog Gastrotheca riobambae, only involution occurred during gastrulation. The processes of archenteron and notochord elongation and convergence and extension were postgastrulation events. We produced an Ab against the homeodomain protein Lim1 from X. laevis as a tool for the comparative analysis of development. By the expression of Lim1, we were able to identify the dorsal side of the G. riobambae early gastrula, which otherwise was difficult to detect. Moreover, the Lim1 expression in the dorsal lip of the blastopore and notochord differed among the studied frogs, indicating variation in the timing of developmental events. The variation encountered gives evidence of the modular character of frog gastrulation. PMID:17606898

  5. The Ups and Downs of Frogs.

    ERIC Educational Resources Information Center

    Greene, Janice Schnake; Tamme, Tina

    2001-01-01

    Presents a science activity in which students simulate increases and decreases in frog populations to get a better understanding of different environmental issues affecting animal populations. Includes simulations for both natural frog populations as well as populations affected by human activities. (YDS)

  6. Semi-automated identification of leopard frogs

    USGS Publications Warehouse

    Petrovska-Delacrétaz, Dijana; Edwards, Aaron; Chiasson, John; Chollet, Gérard; Pilliod, David S.

    2014-01-01

    Principal component analysis is used to implement a semi-automatic recognition system to identify recaptured northern leopard frogs (Lithobates pipiens). Results of both open set and closed set experiments are given. The presented algorithm is shown to provide accurate identification of 209 individual leopard frogs from a total set of 1386 images.

  7. The Ups and Downs of Frogs.

    ERIC Educational Resources Information Center

    Greene, Janice Schnake; Tamme, Tina

    2001-01-01

    Presents a science activity in which students simulate increases and decreases in frog populations to get a better understanding of different environmental issues affecting animal populations. Includes simulations for both natural frog populations as well as populations affected by human activities. (YDS)

  8. Speciation: frog mimics prefer their own.

    PubMed

    Mallet, James

    2014-11-17

    Ranitomeya poison frogs in the Peruvian Amazon are a rare example of Müllerian mimicry in vertebrates. These frogs also prefer to court same-coloured mimics. This suggests that divergence in mimicry plays a role in reproductive isolation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Enhancement of broiler litter to improve the fertilizer quality of litter

    SciTech Connect

    Ransom, J.M.; Strickland, R.C.

    1992-12-01

    This document presents efforts to utilize poultry litter for feed, fertilizer, and soil amendments. Historical and programmatic efforts by TVA are discussed. Current methods of drying and pelleting the litter, along with more direct methods of composting are reported.

  10. Enhancement of broiler litter to improve the fertilizer quality of litter

    SciTech Connect

    Ransom, J.M.; Strickland, R.C.

    1992-01-01

    This document presents efforts to utilize poultry litter for feed, fertilizer, and soil amendments. Historical and programmatic efforts by TVA are discussed. Current methods of drying and pelleting the litter, along with more direct methods of composting are reported.

  11. Cigarette Litter: Smokers’ Attitudes and Behaviors

    PubMed Central

    Rath, Jessica M.; Rubenstein, Rebecca A.; Curry, Laurel E.; Shank, Sarah E.; Cartwright, Julia C.

    2012-01-01

    Cigarette butts are consistently the most collected items in litter clean-up efforts, which are a costly burden to local economies. In addition, tobacco waste may be detrimental to our natural environment. The tobacco industry has conducted or funded numerous studies on smokers’ littering knowledge and behavior, however, non-industry sponsored research is rare. We sought to examine whether demographics and smokers’ knowledge and beliefs toward cigarette waste as litter predicts littering behavior. Smokers aged 18 and older (n = 1,000) were interviewed about their knowledge and beliefs towards cigarette waste as litter. Respondents were members of the Research Now panel, an online panel of over three million respondents in the United States. Multivariate logistic regressions were conducted to determine factors significantly predictive of ever having littered cigarette butts or having littered cigarette butts within the past month (p-value < 0.05). The majority (74.1%) of smokers reported having littered cigarette butts at least once in their life, by disposing of them on the ground or throwing them out of a car window. Over half (55.7%) reported disposing of cigarette butts on the ground, in a sewer/gutter, or down a drain in the past month. Those who did not consider cigarette butts to be litter were over three and half times as likely to report having ever littered cigarette butts (OR = 3.68, 95%CI = 2.04, 6.66) and four times as likely to have littered cigarette butts in the past month (OR = 4.00, 95%CI = 2.53, 6.32). Males were significantly more likely to have littered cigarette butts in the past month compared to females (OR = 1.49, 95%CI = 1.14, 1.94). Holding the belief that cigarette butts are not litter was the only belief in this study that predicted ever or past-month littering of cigarette waste. Messages in anti-cigarette-litter campaigns should emphasize that cigarette butts are not just litter but are toxic waste and are harmful when disposed of

  12. Cigarette litter: smokers' attitudes and behaviors.

    PubMed

    Rath, Jessica M; Rubenstein, Rebecca A; Curry, Laurel E; Shank, Sarah E; Cartwright, Julia C

    2012-06-01

    Cigarette butts are consistently the most collected items in litter clean-up efforts, which are a costly burden to local economies. In addition, tobacco waste may be detrimental to our natural environment. The tobacco industry has conducted or funded numerous studies on smokers' littering knowledge and behavior, however, non-industry sponsored research is rare. We sought to examine whether demographics and smokers' knowledge and beliefs toward cigarette waste as litter predicts littering behavior. Smokers aged 18 and older (n = 1,000) were interviewed about their knowledge and beliefs towards cigarette waste as litter. Respondents were members of the Research Now panel, an online panel of over three million respondents in the United States. Multivariate logistic regressions were conducted to determine factors significantly predictive of ever having littered cigarette butts or having littered cigarette butts within the past month (p-value < 0.05). The majority (74.1%) of smokers reported having littered cigarette butts at least once in their life, by disposing of them on the ground or throwing them out of a car window. Over half (55.7%) reported disposing of cigarette butts on the ground, in a sewer/gutter, or down a drain in the past month. Those who did not consider cigarette butts to be litter were over three and half times as likely to report having ever littered cigarette butts (OR = 3.68, 95%CI = 2.04, 6.66) and four times as likely to have littered cigarette butts in the past month (OR = 4.00, 95%CI = 2.53, 6.32). Males were significantly more likely to have littered cigarette butts in the past month compared to females (OR = 1.49, 95%CI = 1.14, 1.94). Holding the belief that cigarette butts are not litter was the only belief in this study that predicted ever or past-month littering of cigarette waste. Messages in anti-cigarette-litter campaigns should emphasize that cigarette butts are not just litter but are toxic waste and are harmful when disposed of

  13. Interaction of initial litter quality and thinning intensity on litter decomposition rate, nitrogen accumulation and release in a pine plantation

    Treesearch

    Xiao Chen; Deborah Page-Dumroese; Ruiheng Lv; Weiwei Wang; Guolei Li; Yong. Liu

    2014-01-01

    Thinning alters litter quality and microclimate under forests. Both of these two changes after thinning induce alterations of litter decomposition rates and nutrient cycling. However, a possible interaction between these two changes remains unclear. We placed two types of litter (LN, low N concentration litter; HN, high N concentration litter) in a Chinese pine (Pinus...

  14. McDonald's Litter Hunt: A Community Litter Control System for Youth.

    ERIC Educational Resources Information Center

    McNees, M. Patrick; And Others

    1979-01-01

    Describes a community litter control program. Special adhesive stickers were randomly placed on existing litter throughout a community and youth were rewarded with special prizes for participating in the program. Litter was reduced 32 percent across the city. (Author/MA)

  15. Litter composition effects on decomposition across the litter-soil interface

    EPA Science Inventory

    Background/Question/Methods Many studies have investigated the influence of plant litter species composition on decomposition dynamics, but given the variety of communities and environments around the world, a variety of consequences of litter-mixing have been reported. Litter ...

  16. McDonald's Litter Hunt: A Community Litter Control System for Youth.

    ERIC Educational Resources Information Center

    McNees, M. Patrick; And Others

    1979-01-01

    Describes a community litter control program. Special adhesive stickers were randomly placed on existing litter throughout a community and youth were rewarded with special prizes for participating in the program. Litter was reduced 32 percent across the city. (Author/MA)

  17. Litter composition effects on decomposition across the litter-soil interface

    EPA Science Inventory

    Background/Question/Methods Many studies have investigated the influence of plant litter species composition on decomposition dynamics, but given the variety of communities and environments around the world, a variety of consequences of litter-mixing have been reported. Litter ...

  18. Population density of tropical forest frogs: relation to retreat sites.

    PubMed

    Stewart, M M; Pough, F H

    1983-08-05

    The forest frog Eleutherodactylus coqui defends specific sites for retreats and nests in the Luquillo Forest, Puerto Rico. The hypothesis that shortages of nest and retreat sites limit population size was tested by placing 100 bamboo frog houses in plots measuring 100 square meters in areas of high frog density. These new sites were readily adopted by adult frogs. After one year, experimental plots had significantly more nests and frogs of all sizes than did control plots.

  19. Tadpoles of Early Breeding Amphibians are Negatively Affected by Leaf Litter From Invasive Chinese Tallow Trees

    NASA Astrophysics Data System (ADS)

    Leonard, N. E.

    2005-05-01

    As wetlands are invaded by Chinese tallow trees (Triadica sebifera), native trees are displaced and detrital inputs to amphibian breeding ponds are altered. I used a mesocosm experiment to examine the effect of Chinese tallow leaf litter on the survival to, size at, and time to metamorphosis of amphibian larvae. Fifty 1000-L cattle watering tanks were treated with 1500 g dry weight of one of five leaf litter treatments: Chinese tallow, laurel oak (Quercus laurifolia), water tupelo (Nyssa aquatica), slash pine (Pinus elliottii), or a 3:1:1:1 mixture. Each tank received 45 tadpoles of Pseudacris feriarum, Bufo terrestris, and Hyla cinerea in sequence according to their natural breeding phonologies. Every Pseudacris feriarum and Bufo terrestris tadpole exposed to Chinese tallow died prior to metamorphosis. Hyla cinerea survival in tanks with tallow-only was significantly lower than that observed for all other leaf treatments. Hyla cinerea tadpoles from tallow-only and mixed-leaf treatments were larger at metamorphosis and transformed faster than those in tanks with native leaves only. These results suggest that Chinese tallow leaf litter may negatively affect tadpoles of early breeding frogs and that Chinese tallow invasion may change the structure of amphibian communities in temporary ponds.

  20. Extreme variation in the atrial septation of caecilians (Amphibia: Gymnophiona)

    PubMed Central

    de Bakker, Desiderius M; Wilkinson, Mark; Jensen, Bjarke

    2015-01-01

    Caecilians (order Gymnophiona) are elongate, limbless, snake-like amphibians that are the sister-group (closest relatives) of all other recent amphibians (frogs and salamanders). Little is known of their cardiovascular anatomy and physiology, but one nearly century old study suggests that Hypogeophis (family Indotyphlidae), commonly relied upon as a representative caecilian species, has atrial septation in the frontal plane and more than one septum. In contrast, in other vertebrates there generally is one atrial septum in the sagittal plane. We studied the adult heart of Idiocranium (also Indotyphlidae) using immunohistochemistry and confirm that the interatrial septum is close to the frontal plane. Additionally, a parallel right atrial septum divides three-fourths of the right atrial cavity of this species. Idiocranium embryos in the Hill collection reveal that atrial septation initiates in the sagittal plane as in other tetrapods. Late developmental stages, however, see a left-ward shift of visceral organs and a concordant rotation of the atria that reorients the atrial septa towards the frontal plane. The gross anatomies of species from six other caecilian families reveal that (i) the right atrial septum developed early in caecilian evolution (only absent in Rhinatrematidae) and that (ii) rotation of the atria evolved later and its degree varies between families. In most vertebrates a prominent atrial trabeculation associates with the sinuatrial valve, the so-called septum spurium, and the right atrial septum seems homologous to this trabeculation but much more developed. The right atrial septum does not appear to be a consequence of body elongation because it is absent in some caecilians and in snakes. The interatrial septum of caecilians shares multiple characters with the atrial septum of lungfishes, salamanders and the embryonic septum primum of amniotes. In conclusion, atrial septation in caecilians is based on evolutionarily conserved structures but

  1. Chromosome Banding in Amphibia. XXXII. The Genus Xenopus (Anura, Pipidae).

    PubMed

    Schmid, Michael; Steinlein, Claus

    2015-01-01

    Mitotic chromosomes of 16 species of the frog genus Xenopus were prepared from kidney and lung cell cultures. In the chromosomes of 7 species, high-resolution replication banding patterns could be induced by treating the cultures with 5-bromodeoxyuridine (BrdU) and deoxythymidine (dT) in succession, and in 6 of these species the BrdU/dT-banded chromosomes could be arranged into karyotypes. In the 3 species of the clade with 2n = 20 and 4n = 40 chromosomes (X. tropicalis, X. epitropicalis, X. new tetraploid 1), as well as in the 3 species with 4n = 36 chromosomes (X. laevis, X. borealis, X. muelleri), the BrdU/dT-banded karyotypes show a high degree of homoeology, though differences were detected between these groups. Translocations, inversions, insertions or sex-specific replication bands were not observed. Minor replication asynchronies found between chromosomes probably involve heterochromatic regions. BrdU/dT replication banding of Xenopus chromosomes provides the landmarks necessary for the exact physical mapping of genes and repetitive sequences. FISH with an X. laevis 5S rDNA probe detected multiple hybridization sites at or near the long-arm telomeric regions in most chromosomes of X. laevis and X. borealis, whereas in X. muelleri, the 5S rDNA sequences are located exclusively at the long-arm telomeres of a single chromosome pair. Staining with the AT base pair-specific fluorochrome quinacrine mustard revealed brightly fluorescing heterochromatic regions in the majority of X. borealis chromosomes which are absent in other Xenopus species.

  2. Extreme variation in the atrial septation of caecilians (Amphibia: Gymnophiona).

    PubMed

    de Bakker, Desiderius M; Wilkinson, Mark; Jensen, Bjarke

    2015-01-01

    Caecilians (order Gymnophiona) are elongate, limbless, snake-like amphibians that are the sister-group (closest relatives) of all other recent amphibians (frogs and salamanders). Little is known of their cardiovascular anatomy and physiology, but one nearly century old study suggests that Hypogeophis (family Indotyphlidae), commonly relied upon as a representative caecilian species, has atrial septation in the frontal plane and more than one septum. In contrast, in other vertebrates there generally is one atrial septum in the sagittal plane. We studied the adult heart of Idiocranium (also Indotyphlidae) using immunohistochemistry and confirm that the interatrial septum is close to the frontal plane. Additionally, a parallel right atrial septum divides three-fourths of the right atrial cavity of this species. Idiocranium embryos in the Hill collection reveal that atrial septation initiates in the sagittal plane as in other tetrapods. Late developmental stages, however, see a left-ward shift of visceral organs and a concordant rotation of the atria that reorients the atrial septa towards the frontal plane. The gross anatomies of species from six other caecilian families reveal that (i) the right atrial septum developed early in caecilian evolution (only absent in Rhinatrematidae) and that (ii) rotation of the atria evolved later and its degree varies between families. In most vertebrates a prominent atrial trabeculation associates with the sinuatrial valve, the so-called septum spurium, and the right atrial septum seems homologous to this trabeculation but much more developed. The right atrial septum does not appear to be a consequence of body elongation because it is absent in some caecilians and in snakes. The interatrial septum of caecilians shares multiple characters with the atrial septum of lungfishes, salamanders and the embryonic septum primum of amniotes. In conclusion, atrial septation in caecilians is based on evolutionarily conserved structures but

  3. On the Uniqueness of FROG Methods

    NASA Astrophysics Data System (ADS)

    Bendory, Tamir; Sidorenko, Pavel; Eldar, Yonina C.

    2017-05-01

    The problem of recovering a signal from its power spectrum, called phase retrieval, arises in many scientific fields. One of many examples is ultra-short laser pulse characterization in which the electromagnetic field is oscillating with ~10^15 Hz and phase information cannot be measured directly due to limitations of the electronic sensors. Phase retrieval is ill-posed in most cases as there are many different signals with the same Fourier transform magnitude. To overcome this fundamental ill-posedness, several measurement techniques are used in practice. One of the most popular methods for complete characterization of ultra-short laser pulses is the Frequency-Resolved Optical Gating (FROG). In FROG, the acquired data is the power spectrum of the product of the unknown pulse with its delayed replica. Therefore the measured signal is a quartic function of the unknown pulse. A generalized version of FROG, where the delayed replica is replaced by a second unknown pulse, is called blind FROG. In this case, the measured signal is quadratic with respect to both pulses. In this letter we introduce and formulate FROG-type techniques. We then show that almost all band-limited signals are determined uniquely, up to trivial ambiguities, by blind FROG measurements (and thus also by FROG), if in addition we have access to the signals power spectrum.

  4. Role of litter decomposition sensitivity to water content in non-additive litter mixture effect: theoretical demonstration and validation with a peatland litter experiment

    NASA Astrophysics Data System (ADS)

    Gogo, Sébastien; Leroy, Fabien; Zoccatelli, Renata; Bernard-Jannin, Léonard; Laggoun-Défarge, Fatima

    2017-04-01

    In this work, we showed theoretically that differences in litter water content, evaporation rate and reaction rate sensitivity to water content can give account of non-additive litter mixture effect. More specifically two litters with the same dependence to litter water content and contrasted water content, and 2 litters with contrasted decomposition sensitivity to litter water content can exert synergistic mixture effect on decomposition when the 2 litters interact. In these situations, water can flow from the wettest to the driest litter, changing the whole reaction rate without changing the whole litter water content. The reaction rate increase of the litter receiving the water was relatively more important than the reaction rate decrease of the litter supplying the water. These theoretical considerations were validated with experimental data. Sphagnum rubellum and Molinia caerulea decompose faster in measured mixture than expected from the rates obtained in monoculture incubation. Sphagnum rubellum litter can contain more water, which evaporates at a slower rate than Molinia caerulea. It is thus proposed that water flowed from Sphagnum rubellum litter to the Molinia caerulea litter, with a substantial increase of the decomposition of the latter. The physical and biochemical litter characteristics towards water explains a fraction of the synergistic effect of mixing the 2 litters, which suggests that other factors intervene in this effect, such as the carbon substrate.

  5. Effects of Litter Manipulation on Litter Decomposition in a Successional Gradients of Tropical Forests in Southern China

    PubMed Central

    Chen, Hao; Gurmesa, Geshere A.; Liu, Lei; Zhang, Tao; Fu, Shenglei; Liu, Zhanfeng; Dong, Shaofeng; Ma, Chuan; Mo, Jiangming

    2014-01-01

    Global changes such as increasing CO2, rising temperature, and land-use change are likely to drive shifts in litter inputs to forest floors, but the effects of such changes on litter decomposition remain largely unknown. We initiated a litter manipulation experiment to test the response of litter decomposition to litter removal/addition in three successional forests in southern China, namely masson pine forest (MPF), mixed coniferous and broadleaved forest (MF) and monsoon evergreen broadleaved forest (MEBF). Results showed that litter removal decreased litter decomposition rates by 27%, 10% and 8% and litter addition increased litter decomposition rates by 55%, 36% and 14% in MEBF, MF and MPF, respectively. The magnitudes of changes in litter decomposition were more significant in MEBF forest and less significant in MF, but not significant in MPF. Our results suggest that change in litter quantity can affect litter decomposition, and this impact may become stronger with forest succession in tropical forest ecosystem. PMID:24901698

  6. Effects of litter manipulation on litter decomposition in a successional gradients of tropical forests in southern China.

    PubMed

    Chen, Hao; Gurmesa, Geshere A; Liu, Lei; Zhang, Tao; Fu, Shenglei; Liu, Zhanfeng; Dong, Shaofeng; Ma, Chuan; Mo, Jiangming

    2014-01-01

    Global changes such as increasing CO2, rising temperature, and land-use change are likely to drive shifts in litter inputs to forest floors, but the effects of such changes on litter decomposition remain largely unknown. We initiated a litter manipulation experiment to test the response of litter decomposition to litter removal/addition in three successional forests in southern China, namely masson pine forest (MPF), mixed coniferous and broadleaved forest (MF) and monsoon evergreen broadleaved forest (MEBF). Results showed that litter removal decreased litter decomposition rates by 27%, 10% and 8% and litter addition increased litter decomposition rates by 55%, 36% and 14% in MEBF, MF and MPF, respectively. The magnitudes of changes in litter decomposition were more significant in MEBF forest and less significant in MF, but not significant in MPF. Our results suggest that change in litter quantity can affect litter decomposition, and this impact may become stronger with forest succession in tropical forest ecosystem.

  7. Leaf Litter Mixtures Alter Microbial Community Development: Mechanisms for Non-Additive Effects in Litter Decomposition

    PubMed Central

    Chapman, Samantha K.; Newman, Gregory S.; Hart, Stephen C.; Schweitzer, Jennifer A.; Koch, George W.

    2013-01-01

    To what extent microbial community composition can explain variability in ecosystem processes remains an open question in ecology. Microbial decomposer communities can change during litter decomposition due to biotic interactions and shifting substrate availability. Though relative abundance of decomposers may change due to mixing leaf litter, linking these shifts to the non-additive patterns often recorded in mixed species litter decomposition rates has been elusive, and links community composition to ecosystem function. We extracted phospholipid fatty acids (PLFAs) from single species and mixed species leaf litterbags after 10 and 27 months of decomposition in a mixed conifer forest. Total PLFA concentrations were 70% higher on litter mixtures than single litter types after 10 months, but were only 20% higher after 27 months. Similarly, fungal-to-bacterial ratios differed between mixed and single litter types after 10 months of decomposition, but equalized over time. Microbial community composition, as indicated by principal components analyses, differed due to both litter mixing and stage of litter decomposition. PLFA biomarkers a15∶0 and cy17∶0, which indicate gram-positive and gram-negative bacteria respectively, in particular drove these shifts. Total PLFA correlated significantly with single litter mass loss early in decomposition but not at later stages. We conclude that litter mixing alters microbial community development, which can contribute to synergisms in litter decomposition. These findings advance our understanding of how changing forest biodiversity can alter microbial communities and the ecosystem processes they mediate. PMID:23658639

  8. Broiler house litter sampling: the final frontier

    USDA-ARS?s Scientific Manuscript database

    Today, the sustainability of broiler operations reaches beyond the need for litter nutrient management plans that came to the forefront of the industry’s attention in the last fifteen years. Thorough characterization of litter within houses provides the basis for emission models to benefit growers,...

  9. 33 CFR 144.01-35 - Litter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Litter. 144.01-35 Section 144.01-35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-35 Litter. On each...

  10. Poultry litter application on pastures and hayfields

    USDA-ARS?s Scientific Manuscript database

    Poultry litter is widely used on pastures and hayfields in Georgia. There are many benefits when it is used wisely. Producers should use nutrient management planning and recommended rates to ensure poultry litter is used in ways that maximize its benefits without harming the environment....

  11. Enzymatic activities in coniferous leaf litter

    SciTech Connect

    Spalding, B.P.

    1980-07-01

    Assays for measuring the activities of cellulase, xylanase, mannase, amylase, ..beta..-glucosidase, invertase, and protease employing buffered suspensions of ground coniferous and deciduous leaf litter exhibited zero-order kinetics. Only a small percentage of the whole-litter activities of invertase, ..beta..-glucosidase, and protease were extractable into 0.05M potassium acetate, pH 5.0; however, extractable activities of cellulase and xylanase represented from 39 to 174% of the whole-litter activities indicating their soluble exocellar nature. Extractable protease and amylase activities were best correlated with the average daily rates of CO/sub 2/ evolution in a group of 90 leaf litter samples equally representing 18 coniferous species. Enzymatic activities were readily detectable in extracts of all samples but classification of the samples by species provided little differentiation in the distribution of either enzymatic activities or rates of CO/sub 2/ evolution. Mannase, cellulase, and xylanase activities were well-correlated with each other in all samples. Assays attempting to measure a pool of readily-metabolizable substances in litter by extractable reducing substances, ninhydrin-positive substances, glucose, and phenolics failed to show correlation coefficients >0.41 with rates of CO/sub 2/ evolution. Addition of D-(+)-catechin to litter extracts, up to levels equivalent to those observed in the group of samples, did not inhibit any carbohydrase thus suggesting the lack of inhibition of litter-decomposing enzymes by the concentrations of phenolics present in these coniferous leaf litters.

  12. Eleutherodactylus frog introductions to Hawaii

    USGS Publications Warehouse

    Kraus, Fred; Campbell, Earl W.; Allison, Allen; Pratt, Thane K.

    1999-01-01

    As an oceanic archipelago isolated from continental source areas, Hawaii lacks native terrestrial reptiles and amphibians, Polynesians apparently introduced seven gecko and skink species after discovering the islands approximately 1500 years ago, and another 15 reptiles and five frogs have been introduced in the last century and a half (McKeown 1996). The Polynesian introductions are probably inadvertent because the species involved are known stowaway dispersers (Gibbons 1985; Dye and Steadman 1990), In contrast, most of the herpetological introductions since European contact with Hawaii have been intentional. Several frog species were released for biocontrol of insects (e.g., Dendrobates auratus, Bufo marinus, Rana rugosa, Bryan 1932; Oliver and Shaw 1953), and most of the remaining species are released or escaped pets (e.g., Phelsuma spp., Chamaeleo jacksonii, Iguana iguana, McKeown 1996), Government-approved releases have not occurred for many years, but the rate of establishment of new species has increased in the past few decades because of the importation and subsequent release of pets.

  13. Mechanics of the frog ear

    PubMed Central

    van Dijk, Pim; Mason, Matthew J.; Schoffelen, Richard L. M.; Narins, Peter M.; Meenderink, Sebastiaan W. F.

    2010-01-01

    The frog inner ear contains three regions that are sensitive to airborne sound and which are functionally distinct. (1) The responses of nerve fibres innervating the low-frequency, rostral part of the amphibian papilla (AP) are complex. Electrical tuning of hair cells presumably contributes to the frequency selectivity of these responses. (2) The caudal part of the AP covers the mid-frequency portion of the frog's auditory range. It shares the ability to generate both evoked and spontaneous otoacoustic emissions with the mammalian cochlea and other vertebrate ears. (3) The basilar papilla functions mainly as a single auditory filter. Its simple anatomy and function provide a model system for testing hypotheses concerning emission generation. Group delays of stimulus frequency otoacoustic emissions (SFOAEs) from the basilar papilla are accounted for by assuming that they result from forward and reverse transmission through the middle ear, a mechanical delay due to tectorial membrane filtering and a rapid forward and reverse propagation through the inner ear fluids, with negligible delay. PMID:20149854

  14. FROGS (Friends of Granite) Report Winter 1989

    NASA Astrophysics Data System (ADS)

    The purpose of FROGS reports is to disseminate information and stimulate thinking about felsic magmatism granitoids in particular. We publish semiannually, as part of VGP News, brief updates from investigators whose current research concerns felsic magmatism, information about events and publications that are relevant to granitoids, and commentaries on new and controversial themes. FROGS Reports is critically dependent on response from people interested in these topics. Please keep me (Calvin Miller, 6028B, Vanderbilt University, Nashville, TN 37235) informed about upcoming or recent conferences, major publications, and your own research. Also, please send me your suggestions for topics for pertinent commentaries for FROGS reports (or volunteer to write one yourself!).

  15. Poultry litter toxicity comparison from various bioassays

    SciTech Connect

    Gupta, G.; Kelly, P. )

    1992-01-01

    Poultry litter contains many toxic chemicals including Cu, As, Pb, Cd, Hg, Se and PCBs. Poultry litter leachate has been shown to be more toxic to marine luminescent organisms (Photobacterium phosphoreum) than other farm animal manures. A comparison of toxicity of the poultry litter leachate was undertaken using various bioassays. The EC{sub 50} (or LC{sub 50}) value for the leachate with the Microtox and Daphnia bioassays was 2.9 g/L/ Nitrobacter and Pseudomonas bioassays were not useful in determining the leachate toxicity because of the nutritional properties of the litter. Poultry litter leachate was found to be mutagenic to strains TA 97, TA 98, TA 100 and TA 102 using the Ames Test.

  16. Impact of litter quantity on the soil bacteria community during the decomposition of Quercus wutaishanica litter.

    PubMed

    Zeng, Quanchao; Liu, Yang; An, Shaoshan

    2017-01-01

    The forest ecosystem is the main component of terrestrial ecosystems. The global climate and the functions and processes of soil microbes in the ecosystem are all influenced by litter decomposition. The effects of litter decomposition on the abundance of soil microorganisms remain unknown. Here, we analyzed soil bacterial communities during the litter decomposition process in an incubation experiment under treatment with different litter quantities based on annual litterfall data (normal quantity, 200 g/(m(2)/yr); double quantity, 400 g/(m(2)/yr) and control, no litter). The results showed that litter quantity had significant effects on soil carbon fractions, nitrogen fractions, and bacterial community compositions, but significant differences were not found in the soil bacterial diversity. The normal litter quantity enhanced the relative abundance of Actinobacteria and Firmicutes and reduced the relative abundance of Bacteroidetes, Plantctomycets and Nitrospiare. The Beta-, Gamma-, and Deltaproteobacteria were significantly less abundant in the normal quantity litter addition treatment, and were subsequently more abundant in the double quantity litter addition treatment. The bacterial communities transitioned from Proteobacteria-dominant (Beta-, Gamma-, and Delta) to Actinobacteria-dominant during the decomposition of the normal quantity of litter. A cluster analysis showed that the double litter treatment and the control had similar bacterial community compositions. These results suggested that the double quantity litter limited the shift of the soil bacterial community. Our results indicate that litter decomposition alters bacterial dynamics under the accumulation of litter during the vegetation restoration process, which provides important significant guidelines for the management of forest ecosystems.

  17. Microarthropods accelerate litter decomposition and alter the fate of litter carbon and nitrogen in the soil

    NASA Astrophysics Data System (ADS)

    Soong, Jennifer; Horton, Andrew; Wall, Diana; Cotrufo, Francesca

    2015-04-01

    Soil fauna have been found to accelerate litter decomposition in some ecosystems, with calls for the need to include them in global models of C and N cycling. However, their influence on the fate of decomposing litter C and N is not clear. Does the acceleration of mass loss affect how much litter C and N end up stored as soil organic matter (SOM), or how much C and N are lost to the atmosphere during decomposition? We will present the results from our three-year, 100% mass loss, tracking of 13C and 15N labeled Andropogon gerardii leaf litter decomposing at a tallgrass prairie site, where we used a naphthalene treatment to suppress microarthropods and examine their effects on the fate of decomposing litter C and N. Initially, leaching was the main pathway of litter inputs to the mineral associated SOM. We found that microarthropods accelerated the first 18 months of litter mass loss, but after 24 months mass loss rates converged. This early acceleration of mass loss was associated with an increase of litter fragment inputs to the soil. This increase in litter inputs to the soil caused by microarthropods resulted in an increase in microbial uptake of litter C (measured by tracing 13C into phospholipid fatty acids), and a shift in the microbial community. The C:N ratio of litter inputs to the soil was significantly increased by the presence of microarthropods. Together these results demonstrate how microarthropods accelerate shredding, mass loss, and litter fragment inputs to the soil during the early stages of decomposition but they do not affect the total amount of litter contribution to SOM over the entire course of decomposition. However, microarthropods do alter the C:N composition of litter inputs to the soil through their top-down influence on the microbial community responsible for decomposing and transforming litter inputs to the soil. Our results reveal the complex interactions between microarthropods, litter mass loss, soil microbes and C:N dynamics, and

  18. California Red-legged Frog - Stipulated Injunction

    EPA Pesticide Factsheets

    EPA will make effects determinations and initiate consultation with the U.S. Fish and Wildlife Service, regarding the potential effects of 66 pesticide active ingredient registrations on the California red-legged frog.

  19. Meeting the "Standards" with Vanishing Frogs.

    ERIC Educational Resources Information Center

    Davidson, Cindy B.; Matthews, Catherine E.; Patrick, Patricia

    2001-01-01

    Explains methods for introducing high school students to the issue of the declining amphibian population. Plays the game Frogs' Futures following a seminar as an instructional strategy. Describes the game, procedures, and rules. (YDS)

  20. Meeting the "Standards" with Vanishing Frogs.

    ERIC Educational Resources Information Center

    Davidson, Cindy B.; Matthews, Catherine E.; Patrick, Patricia

    2001-01-01

    Explains methods for introducing high school students to the issue of the declining amphibian population. Plays the game Frogs' Futures following a seminar as an instructional strategy. Describes the game, procedures, and rules. (YDS)

  1. FROGS Report Friends of Granite Summer 1989

    NASA Astrophysics Data System (ADS)

    FROGS Reports present information on current research relevant to felsic magmatism, including commentaries on problems of current interest. Please contact Calvin Miller (6028B, Vanderbilt University, Nashville, TN 37235) concerning your own research, conferences, and ideas for stimulating commentaries.

  2. Internal fertilization in an oviparous frog.

    PubMed

    Townsend, D S; Stewart, M M; Pough, F H; Brussard, P F

    1981-04-24

    Eleutherodactylus coqui, an oviparous frog, undergoes internal fertilization. If this mode of fertilization occurs in other species of anurans, interpretations of anuran reproductive strategies based on the assumption of external fertilization must be reviewed.

  3. Study on Hydrological Functions of Litter Layers in North China

    PubMed Central

    Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

    2013-01-01

    Canopy interception, throughfall, stemflow, and runoff have received considerable attention during the study of water balance and hydrological processes in forested ecosystems. Past research has either neglected or underestimated the role of hydrological functions of litter layers, although some studies have considered the impact of various characteristics of rainfall and litter on litter interception. Based on both simulated rainfall and litter conditions in North China, the effect of litter mass, rainfall intensity and litter type on the maximum water storage capacity of litter (S) and litter interception storage capacity (C) were investigated under five simulated rainfall intensities and four litter masses for two litter types. The results indicated: 1) the S values increased linearly with litter mass, and the S values of broadleaf litter were on average 2.65 times larger than the S values of needle leaf litter; 2) rainfall intensity rather than litter mass determined the maximum interception storage capacity (Cmax); Cmax increased linearly with increasing rainfall intensity; by contrast, the minimum interception storage capacity (Cmin) showed a linear relationship with litter mass, but a poor correlation with rainfall intensity; 3) litter type impacted Cmax and Cmin; the values of Cmax and Cmin for broadleaf litter were larger than those of needle leaf litter, which indicated that broadleaf litter could intercepte and store more water than needle leaf litter; 4) a gap existed between Cmax and Cmin, indicating that litter played a significant role by allowing rainwater to infiltrate or to produce runoff rather than intercepting it and allowing it to evaporate after the rainfall event; 5) Cmin was always less than S at the same litter mass, which should be considered in future interception predictions. Vegetation and precipitation characteristics played important roles in hydrological characteristics. PMID:23936188

  4. Effects of Nitrogen Addition on Litter Decomposition and CO2 Release: Considering Changes in Litter Quantity.

    PubMed

    Li, Hui-Chao; Hu, Ya-Lin; Mao, Rong; Zhao, Qiong; Zeng, De-Hui

    2015-01-01

    This study aims to evaluate the impacts of changes in litter quantity under simulated N deposition on litter decomposition, CO2 release, and soil C loss potential in a larch plantation in Northeast China. We conducted a laboratory incubation experiment using soil and litter collected from control and N addition (100 kg ha-1 year-1 for 10 years) plots. Different quantities of litter (0, 1, 2 and 4 g) were placed on 150 g soils collected from the same plots and incubated in microcosms for 270 days. We found that increased litter input strongly stimulated litter decomposition rate and CO2 release in both control and N fertilization microcosms, though reduced soil microbial biomass C (MBC) and dissolved inorganic N (DIN) concentration. Carbon input (C loss from litter decomposition) and carbon output (the cumulative C loss due to respiration) elevated with increasing litter input in both control and N fertilization microcosms. However, soil C loss potentials (C output-C input) reduced by 62% in control microcosms and 111% in N fertilization microcosms when litter addition increased from 1 g to 4 g, respectively. Our results indicated that increased litter input had a potential to suppress soil organic C loss especially for N addition plots.

  5. Effects of Nitrogen Addition on Litter Decomposition and CO2 Release: Considering Changes in Litter Quantity

    PubMed Central

    Li, Hui-Chao; Hu, Ya-Lin; Mao, Rong; Zhao, Qiong; Zeng, De-Hui

    2015-01-01

    This study aims to evaluate the impacts of changes in litter quantity under simulated N deposition on litter decomposition, CO2 release, and soil C loss potential in a larch plantation in Northeast China. We conducted a laboratory incubation experiment using soil and litter collected from control and N addition (100 kg ha−1 year−1 for 10 years) plots. Different quantities of litter (0, 1, 2 and 4 g) were placed on 150 g soils collected from the same plots and incubated in microcosms for 270 days. We found that increased litter input strongly stimulated litter decomposition rate and CO2 release in both control and N fertilization microcosms, though reduced soil microbial biomass C (MBC) and dissolved inorganic N (DIN) concentration. Carbon input (C loss from litter decomposition) and carbon output (the cumulative C loss due to respiration) elevated with increasing litter input in both control and N fertilization microcosms. However, soil C loss potentials (C output–C input) reduced by 62% in control microcosms and 111% in N fertilization microcosms when litter addition increased from 1 g to 4 g, respectively. Our results indicated that increased litter input had a potential to suppress soil organic C loss especially for N addition plots. PMID:26657180

  6. PAHs in decaying Quercus ilex leaf litter: mutual effects on litter decomposition and PAH dynamics.

    PubMed

    De Nicola, F; Baldantoni, D; Alfani, A

    2014-11-01

    The investigation of the relationships between litter decomposition and polycyclic aromatic hydrocarbons (PAHs) is important to shed light not only on the effects of these pollutants on fundamental ecosystem processes, such as litter decomposition, but also on the degradation of these pollutants by soil microbial community. This allows to understand the effect of atmospheric PAH contamination on soil PAH content via litterfall. At this aim, we studied mass and PAH dynamics of Quercus ilex leaf litters collected from urban, industrial and remote sites, incubated in mesocosms under controlled conditions for 361d. The results highlighted a litter decomposition rate of leaves sampled in urban>industrial>remote sites; the faster decomposition of litter of the urban site is also related to the low C/N ratio of the leaves. The PAHs showed concentrations at the beginning of the incubation of 887, 650 and 143 ng g(-1)d.w., respectively in leaf litters from urban, industrial and remote sites. The PAHs in litter decreased along the time, with the same trend observed for mass litter, showing the highest decrease at 361 d for the urban leaf litter. Anyway, PAH dynamics in all the litters exhibited two phases of loss, separated by a PAH increase observed at 246 d and mainly linked to benzo[e]pyrene.

  7. Plastic litter in the sea.

    PubMed

    Depledge, M H; Galgani, F; Panti, C; Caliani, I; Casini, S; Fossi, M C

    2013-12-01

    On June 2013 a workshop at the University of Siena (Italy) was organized to review current knowledge and to clarify what is known, and what remains to be investigated, concerning plastic litter in the sea. The content of the workshop was designed to contribute further to the European Marine Strategy Framework Directive (MSFD) following an inaugural workshop in 2012. Here we report a number of statements relevant to policymakers and scientists that was overwhelming agreement from the participants. Many might view this as already providing sufficient grounds for policy action. At the very least, this early warning of the problems that lie ahead should be taken seriously, and serve as a stimulus for further research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. LITTLE FROG ROADLESS AREA, TENNESSEE.

    USGS Publications Warehouse

    Force, Eric R.; Gazdik, Gertrude C.

    1984-01-01

    No mineral-resource potential was identified during studies of the Little Frog Roadless Area, Tennessee. Possibilities exist, however, for the occurrence of massive sulfide-bearing rocks of the type mined in the adjacent Ducktown Basin at depth beneath the roadless area. A possibility also exists for the presence of natural gas in sedimentary rocks at great depth. Insufficient data to support these concepts precludes assessing any of the roadless area as having resource potential. A limited amount of geologic mapping coupled with seismic work would be useful to test whether rocks of the Ducktown Basin are present at depth under the roadless areas. Seismic work and drilling would be necessary also to test for the presence of gas at great depths.

  9. Development of the pseudothumb in frogs

    PubMed Central

    Tokita, Masayoshi; Iwai, Noriko

    2010-01-01

    Frogs have highly conserved hand and foot morphology, possessing four fingers and five toes. As an exception, two Japanese ranid frog species, the Otton frog Babina subaspera and the dagger frog Babina holsti, possess a unique thumb-like structure (the pseudothumb) in the forelimb, giving an appearance of a total of five fingers on the hand. To obtain insights into the developmental mechanisms that generate this novel character, we investigated the hand morphogenesis of the Otton frog. The unique morphological pattern of the pseudothumb was already established in juveniles. Surprisingly, the bud-like structure, which is similar to the area of inductive activity (e.g. feather buds in birds and the carapacial ridge in turtles), was detected over the site where the future prepollex develops in larvae. By contrast, this bud-like structure was not found in larvae of other ranid species. We discuss possible scenarios that would favour the evolution of this very unusual trait in frogs. PMID:20147308

  10. Sound Generating Mechanism of Frog Shaped Guiros

    NASA Astrophysics Data System (ADS)

    Iwatsuki, Nobuyuki; Morikawa, Koichi

    A frog shaped guiro is a wooden percussion instrument with an open-ended cave. By rubbing dorsal fins like saw blades on a back of the guiro with a wooden stick, the guiro generates the sound like a frog's voice. The exciting force, response acceleration and radiating sound pressure were measured with accelerometers on the stick and guiro and a condenser microphone and then the relation between the impulsively exciting force and sound pressure was revealed. A three-dimensional solid model of the guiro was built by use of an X-ray CT scanner device and a finite element model composed of tetrahedral elements was then obtained. The FEM modal analysis revealed that the frog shaped guiro had four dominant modes of vibration which was characterized by motion of mouth of the guiro such as the yawn mode and grinding teeth mode. The frequency spectrum of the sound pressure radiating from the frog shaped guiro excited by sequential impulsive forces moving along the dorsal fins was theoretically estimated. Since the estimated sound pressure agreed well with the measured one, the sound radiating from the guiro like a frog's voice could be reproduced. It was also revealed that the variation of driving point mobility of the dorsal fins and amplitude of the exciting force affected to generate the sound like a frog's voice.

  11. Evolution of alanine:glyoxylate aminotransferase 1 peroxisomal and mitochondrial targeting. A survey of its subcellular distribution in the livers of various representatives of the classes Mammalia, Aves and Amphibia.

    PubMed

    Danpure, C J; Fryer, P; Jennings, P R; Allsop, J; Griffiths, S; Cunningham, A

    1994-08-01

    As part of a wider study on the molecular evolution of alanine:glyoxylate aminotransferase 1 (AGT1) intracellular compartmentalization, we have determined the subcellular distribution of immunoreactive AGT1, using postembedding protein A-gold immunoelectron microscopy, in the livers of various members of the classes Mammalia, Aves, and Amphibia. As far as organellar distribution is concerned, three categories could be distinguished. In members of the first category (type I), all, or nearly all, of the immunoreactive AGT1 was concentrated within the peroxisomes. In the second category (type II), AGT1 was found more evenly distributed in both peroxisomes and mitochondria. In the third category (type III), AGT1 was localized mainly within the mitochondria with much lower, but widely variable, amounts in the peroxisomes. Type I animals include the human, two great apes (gorilla, orangutan), two Old World monkeys (anubis baboon, Japanese macaque), a New World monkey (white-faced Saki monkey), a lago, morph (European rabbit), a bat (Seba's short-tailed fruit bat), two caviomorph rodents (guinea pig, orange-rumped agouti), and two Australian marsupials (koala, Bennett's wallaby). Type II animals include two New World monkeys (common marmoset, cotton-top tamarin), three prosimians (brown lemur, fat-tailed dwarf lemur, pygmy slow loris), five rodents (a hybrid crested porcupine, Colombian ground squirrel, laboratory rat, laboratory mouse, golden hamster), an American marsupial (grey short-tailed opossum), and a bird (raven). Type III animals include the large tree shrew, three insectivores (common Eurasian mole, European hedgehog, house shrew), four carnivores (domestic cat, ocelot, domestic dog, polecat ferret), and an amphibian (common frog). In addition to these categories, some animals (e.g. guinea pig, common frog) possessed significant amounts of cytosolic AGT1. Whereas the subcellular distribution of AGT1 in some orders (e.g. Insectivora and Carnivora) did not appear

  12. Anti-apoptotic response during anoxia and recovery in a freeze-tolerant wood frog (Rana sylvatica)

    PubMed Central

    Gerber, Victoria E.M.; Wijenayake, Sanoji

    2016-01-01

    The common wood frog, Rana sylvatica, utilizes freeze tolerance as a means of winter survival. Concealed beneath a layer of leaf litter and blanketed by snow, these frogs withstand subzero temperatures by allowing approximately 65–70% of total body water to freeze. Freezing is generally considered to be an ischemic event in which the blood oxygen supply is impeded and may lead to low levels of ATP production and exposure to oxidative stress. Therefore, it is as important to selectively upregulate cytoprotective mechanisms such as the heat shock protein (HSP) response and expression of antioxidants as it is to shut down majority of ATP consuming processes in the cell. The objective of this study was to investigate another probable cytoprotective mechanism, anti-apoptosis during oxygen deprivation and recovery in the anoxia tolerant wood frog. In particular, relative protein expression levels of two important apoptotic regulator proteins, Bax and p-p53 (S46), and five anti-apoptotic/pro-survival proteins, Bcl-2, p-Bcl-2 (S70), Bcl-xL, x-IAP, and c-IAP in response to normoxic, 24 Hr anoxic exposure, and 4 Hr recovery stages were assessed in the liver and skeletal muscle using western immunoblotting. The results suggest a tissue-specific regulation of the anti-apoptotic pathway in the wood frog, where both liver and skeletal muscle shows an overall decrease in apoptosis and an increase in cell survival. This type of cytoprotective mechanism could be aimed at preserving the existing cellular components during long-term anoxia and oxygen recovery phases in the wood frog. PMID:27042393

  13. From Virtual Frog to Frog Island: Design Studies in a Development Project.

    ERIC Educational Resources Information Center

    Dev, Parvati; Walker, Decker F.

    1999-01-01

    Explores the efforts of a curriculum development team who set out to create a virtual frog for use in biology education, but instead, after several design studies, developed a virtual world called Frog Island. Argues for incorporating educational design studies into other educational development projects. (CMK)

  14. An implement for subsurface band application of poultry litter

    USDA-ARS?s Scientific Manuscript database

    Broiler litter is commonly used as a fertilizer on pastures and cropland. Poultry litter is typically land-applied by broadcasting the litter on the soil surface. Rain falling on soil to which poultry litter has been applied, may carry phosphorus (P) and nitrogen (N) nutrients from the soil into s...

  15. The Litter Problem. Environmental Education Supplementary Instructional Guide, Secondary Level.

    ERIC Educational Resources Information Center

    Hawaii State Dept. of Education, Honolulu. Office of Instructional Services.

    Presented is a guide for helping secondary school students investigate the litter problem, acquire litter control skills, and develop an anti-litter ethic. The manual contains a hierarchy of learning objectives, a pretest/posttest, background information on litter, and activities keyed to the learning objectives. Each lesson includes brief…

  16. The Litter Problem. Environmental Education Supplementary Instructional Guide, Elementary Level.

    ERIC Educational Resources Information Center

    Hawaii State Dept. of Education, Honolulu. Office of Instructional Services.

    Presented is a guide for helping elementary school students become aware of the litter problem, acquire litter control skills, and develop an anti-litter ethic. The manual contains a hierarchy of learning objectives, a pretest/posttest instrument, background information on litter, and 12 lessons designed to promote attainment of the learning…

  17. Litter quality mediated nitrogen effect on plant litter decomposition regardless of soil fauna presence.

    PubMed

    Zhang, Weidong; Chao, Lin; Yang, Qingpeng; Wang, Qingkui; Fang, Yunting; Wang, Silong

    2016-10-01

    Nitrogen addition has been shown to affect plant litter decomposition in terrestrial ecosystems. The way that nitrogen deposition impacts the relationship between plant litter decomposition and altered soil nitrogen availability is unclear, however. This study examined 18 co-occurring litter types in a subtropical forest in China in terms of their decomposition (1 yr of exposure in the field) with nitrogen addition treatment (0, 0.4, 1.6, and 4.0 mol·N·m(-2) ·yr(-1) ) and soil fauna exclusion (litter bags with 0.1 and 2 cm mesh size). Results showed that the plant litter decomposition rate is significantly reduced because of nitrogen addition; the strength of the nitrogen addition effect is closely related to the nitrogen addition levels. Plant litters with diverse quality responded to nitrogen addition differently. When soil fauna was present, the nitrogen addition effect on medium-quality or high-quality plant litter decomposition rate was -26% ± 5% and -29% ± 4%, respectively; these values are significantly higher than that of low-quality plant litter decomposition. The pattern is similar when soil fauna is absent. In general, the plant litter decomposition rate is decreased by soil fauna exclusion; an average inhibition of -17% ± 1.5% was exhibited across nitrogen addition treatment and litter quality groups. However, this effect is weakly related to nitrogen addition treatment and plant litter quality. We conclude that the variations in plant litter quality, nitrogen deposition, and soil fauna are important factors of decomposition and nutrient cycling in a subtropical forest ecosystem.

  18. Pulse frequency and soil-litter mixing alter the control of cumulative precipitation over litter decomposition.

    PubMed

    Joly, François-Xavier; Kurupas, Kelsey L; Throop, Heather L

    2017-09-01

    Macroclimate has traditionally been considered the predominant driver of litter decomposition. However, in drylands, cumulative monthly or annual precipitation typically fails to predict decomposition. In these systems, the windows of opportunity for decomposer activity may rather depend on the precipitation frequency and local factors affecting litter desiccation, such as soil-litter mixing. We used a full-factorial microcosm experiment to disentangle the relative importance of cumulative precipitation, pulse frequency, and soil-litter mixing on litter decomposition. Decomposition, measured as litter carbon loss, saturated with increasing cumulative precipitation when pulses were large and infrequent, suggesting that litter moisture no longer increased and/or microbial activity was no longer limited by water availability above a certain pulse size. More frequent precipitation pulses led to increased decomposition at high levels of cumulative precipitation. Soil-litter mixing consistently increased decomposition, with greatest relative increase (+194%) under the driest conditions. Collectively, our results highlight the need to consider precipitation at finer temporal scale and incorporate soil-litter mixing as key driver of decomposition in drylands. © 2017 by the Ecological Society of America.

  19. Can't See the Wood for the Litter: Evaluation of Litter Behavior Modification in a Forest

    ERIC Educational Resources Information Center

    Lindemann-Matthies, Petra; Bonigk, Isabel; Benkowitz, Dorothee

    2012-01-01

    This study investigated elementary school children's (n = 171) litter behavior during guided forest tours following two different treatments. Four classes received a verbal appeal not to litter in the forest, while another four classes received both a verbal appeal and a demonstration of the desired litter behavior (picking up litter, putting it…

  20. Can't See the Wood for the Litter: Evaluation of Litter Behavior Modification in a Forest

    ERIC Educational Resources Information Center

    Lindemann-Matthies, Petra; Bonigk, Isabel; Benkowitz, Dorothee

    2012-01-01

    This study investigated elementary school children's (n = 171) litter behavior during guided forest tours following two different treatments. Four classes received a verbal appeal not to litter in the forest, while another four classes received both a verbal appeal and a demonstration of the desired litter behavior (picking up litter, putting it…

  1. No Litter Will Make a Better Place.

    ERIC Educational Resources Information Center

    Rodgers, Amy

    1987-01-01

    Describes a community anti-litter campaign developed by second grades, involving letter writing, dramatics, photography, and the creation of posters and a videotape. Identifies skills from the Kentucky Essential Skills list that were taught by the project. (SV)

  2. Volatile organic compounds from leaves litter.

    PubMed

    Isidorov, Valery; Jdanova, Maria

    2002-09-01

    Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.

  3. Hands-on Science. How Do Polliwogs Become Frogs?

    ERIC Educational Resources Information Center

    Kepler, Lynne

    1993-01-01

    Describes a miniscience unit on frogs for elementary grades that teaches students about how frogs develop from tadpoles and how frogs need water during their entire life cycle. Students learn such skills as observation, collecting, and recording data. Provides addresses for ordering resources for teachers and students. (SM)

  4. 49 CFR 213.141 - Self-guarded frogs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Self-guarded frogs. 213.141 Section 213.141..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.141 Self-guarded frogs. (a) The raised guard on a self-guarded frog shall not be worn more than three-eighths of an inch. (b) If repairs...

  5. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole defect...

  6. 49 CFR 213.141 - Self-guarded frogs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Self-guarded frogs. 213.141 Section 213.141..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.141 Self-guarded frogs. (a) The raised guard on a self-guarded frog shall not be worn more than three-eighths of an inch. (b) If repairs...

  7. 49 CFR 213.141 - Self-guarded frogs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Self-guarded frogs. 213.141 Section 213.141..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.141 Self-guarded frogs. (a) The raised guard on a self-guarded frog shall not be worn more than three-eighths of an inch. (b) If repairs...

  8. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole defect...

  9. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole defect...

  10. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole defect...

  11. 49 CFR 213.141 - Self-guarded frogs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Self-guarded frogs. 213.141 Section 213.141..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.141 Self-guarded frogs. (a) The raised guard on a self-guarded frog shall not be worn more than three-eighths of an inch. (b) If repairs...

  12. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole defect...

  13. 49 CFR 213.141 - Self-guarded frogs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Self-guarded frogs. 213.141 Section 213.141..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.141 Self-guarded frogs. (a) The raised guard on a self-guarded frog shall not be worn more than three-eighths of an inch. (b) If repairs...

  14. Hands-on Science. How Do Polliwogs Become Frogs?

    ERIC Educational Resources Information Center

    Kepler, Lynne

    1993-01-01

    Describes a miniscience unit on frogs for elementary grades that teaches students about how frogs develop from tadpoles and how frogs need water during their entire life cycle. Students learn such skills as observation, collecting, and recording data. Provides addresses for ordering resources for teachers and students. (SM)

  15. Development of behavior in the litter huddle in rat pups: within- and between-litter differences.

    PubMed

    Bautista, Amando; García-Torres, Esmeralda; Prager, Geraldine; Hudson, Robyn; Rödel, Heiko G

    2010-01-01

    Early postnatal growth in mammals can be considerably influenced by litter size and often differs among littermates in relation to birth mass. In a study of Long Evans laboratory rats we asked whether within- and between-litter differences in body mass and growth are related to behavioral development during early postnatal life. For this, we analyzed the amount of general motor activity and the display of directed, seemingly goal-oriented interactions within the litter huddle in previsual pups. During the study period from postnatal days 2 to 11, we found significant changes in pup behavior, showing a nonlinear, quadratic shape. General motor activity and, more specifically, the display of behaviors apparently directed to reaching central positions in the litter huddle increased during the first postnatal days and then decreased again. However, pups from small litters that grow more rapidly than pups from large litters, showed a faster increase in both behaviors, whereas the young from large litters reached a higher maximum. We also found striking within-litter differences in the amount of directed behavior performed by light and heavy pups, with higher levels in the former group, most probably because light pups that have a less favorable body mass-to-volume ratio and more often occupy peripheral positions in the litter huddle, make a greater effort to reach thermally favorable central positions. In conclusion, our study shows there to be consistent between-litter as well as within-litter differences in behavioral patterns during early life. These differences might have important implications for an individual's long-term behavioral and physiological performance.

  16. Frog Swarms: Earthquake Precursors or False Alarms?

    PubMed Central

    Grant, Rachel A.; Conlan, Hilary

    2013-01-01

    Simple Summary Media reports linking unusual animal behaviour with earthquakes can potentially create false alarms and unnecessary anxiety among people that live in earthquake risk zones. Recently large frog swarms in China and elsewhere have been reported as earthquake precursors in the media. By examining international media reports of frog swarms since 1850 in comparison to earthquake data, it was concluded that frog swarms are naturally occurring dispersal behaviour of juveniles and are not associated with earthquakes. However, the media in seismic risk areas may be more likely to report frog swarms, and more likely to disseminate reports on frog swarms after earthquakes have occurred, leading to an apparent link between frog swarms and earthquakes. Abstract In short-term earthquake risk forecasting, the avoidance of false alarms is of utmost importance to preclude the possibility of unnecessary panic among populations in seismic hazard areas. Unusual animal behaviour prior to earthquakes has been reported for millennia but has rarely been scientifically documented. Recently large migrations or unusual behaviour of amphibians have been linked to large earthquakes, and media reports of large frog and toad migrations in areas of high seismic risk such as Greece and China have led to fears of a subsequent large earthquake. However, at certain times of year large migrations are part of the normal behavioural repertoire of amphibians. News reports of “frog swarms” from 1850 to the present day were examined for evidence that this behaviour is a precursor to large earthquakes. It was found that only two of 28 reported frog swarms preceded large earthquakes (Sichuan province, China in 2008 and 2010). All of the reported mass migrations of amphibians occurred in late spring, summer and autumn and appeared to relate to small juvenile anurans (frogs and toads). It was concluded that most reported “frog swarms” are actually normal behaviour, probably caused by

  17. The vocal sac of Hylodidae (Amphibia, Anura): Phylogenetic and functional implications of a unique morphology.

    PubMed

    Elias-Costa, Agustin J; Montesinos, Rachel; Grant, Taran; Faivovich, Julián

    2017-07-25

    Anuran vocal sacs are elastic chambers that recycle exhaled air during vocalizations and are present in males of most species of frogs. Most knowledge of the diversity of vocal sacs relates to external morphology; detailed information on internal anatomy is available for few groups of frogs. Frogs of the family Hylodidae, which is endemic to the Atlantic Forest of Brazil and adjacent Argentina and Paraguay, have three patterns of vocal sac morphology-that is, single, subgular; paired, lateral; and absent. The submandibular musculature and structure of the vocal sac mucosa (the internal wall of the vocal sac) of exemplar species of this family and relatives were studied. In contrast to previous accounts, we found that all species of Crossodactylus and Hylodes possess paired, lateral vocal sacs, with the internal mucosa of each sac being separate from the contralateral one. Unlike all other frogs for which data are available, the mucosa of the vocal sacs in these genera is not supported externally by the mm. intermandibularis and interhyoideus. Rather, the vocal sac mucosa projects through the musculature and is free in the submandibular lymphatic sac. The presence of paired, lateral vocal sacs, the internal separation of the sac mucosae, and their projection through the m. interhyoideus are synapomorphies of the family. Furthermore, the specific configuration of the m. interhyoideus allows asymmetric inflation of paired vocal sacs, a feature only reported in species of these diurnal, stream-dwelling frogs. © 2017 Wiley Periodicals, Inc.

  18. Pain perception and anaesthesia in research frogs.

    PubMed

    Guénette, Sarah Annie; Giroux, Marie-Chantal; Vachon, Pascal

    2013-01-01

    Frogs possess pain receptors and pathways that support processing and perception of noxious stimuli however the level of organization is less well structured compared to mammals. It was long believed that the experience of pain was limited to 'higher' phylums of the animal kingdom. However, it is now commonly accepted that amphibians possess neuro-anatomical pathways conductive of a complete nociceptive experience. Xenopus laevis frogs have been one of the most popular aquatic research models for developmental studies and genetic research. These frogs have been extensively use in research for their eggs, that can be collected following hormonal stimulation either naturally or by surgical intervention. Many anaesthetics have been used in amphibians such as bath solutions of MS-222, benzocaine and eugenol as well as systemic injections of ketamine or tiletamine, barbiturates, propofol and gas administrations of methoxyflurane, halothane and isoflurane. Most of these anaesthetic drugs produce variability in depth and duration of anaesthesia. MS-222 appears to be one of the most reliable anaesthetics. This review will focus on the evidence of pain perception in frogs and will compare the effectiveness and limitations of different anaesthetics used in Xenopus leavis frogs.

  19. THE PROPELLER AND THE FROG

    SciTech Connect

    Pan, Margaret; Chiang, Eugene

    2010-10-20

    'Propellers' in planetary rings are disturbances in ring material excited by moonlets that open only partial gaps. We describe a new type of co-orbital resonance that can explain the observed non-Keplerian motions of propellers. The resonance is between the moonlet underlying the propeller and co-orbiting ring particles downstream of the moonlet where the gap closes. The moonlet librates within the gap about an equilibrium point established by co-orbiting material and stabilized by the Coriolis force. In the limit of small libration amplitude, the libration period scales linearly with the gap azimuthal width and inversely as the square root of the co-orbital mass. The new resonance recalls but is distinct from conventional horseshoe and tadpole orbits; we call it the 'frog' resonance, after the relevant term in equine hoof anatomy. For a ring surface density and gap geometry appropriate for the propeller Bleriot in Saturn's A ring, our theory predicts a libration period of {approx}4 years, similar to the {approx}3.7 year period over which Bleriot's orbital longitude is observed to vary. These librations should be subtracted from the longitude data before any inferences about moonlet migration are made.

  20. The Propeller and the Frog

    NASA Astrophysics Data System (ADS)

    Pan, Margaret; Chiang, Eugene

    2010-10-01

    "Propellers" in planetary rings are disturbances in ring material excited by moonlets that open only partial gaps. We describe a new type of co-orbital resonance that can explain the observed non-Keplerian motions of propellers. The resonance is between the moonlet underlying the propeller and co-orbiting ring particles downstream of the moonlet where the gap closes. The moonlet librates within the gap about an equilibrium point established by co-orbiting material and stabilized by the Coriolis force. In the limit of small libration amplitude, the libration period scales linearly with the gap azimuthal width and inversely as the square root of the co-orbital mass. The new resonance recalls but is distinct from conventional horseshoe and tadpole orbits; we call it the "frog" resonance, after the relevant term in equine hoof anatomy. For a ring surface density and gap geometry appropriate for the propeller Blériot in Saturn's A ring, our theory predicts a libration period of ~4 years, similar to the ~3.7 year period over which Blériot's orbital longitude is observed to vary. These librations should be subtracted from the longitude data before any inferences about moonlet migration are made.

  1. Broiler litter management effects on the nutrient composition of the litter

    USDA-ARS?s Scientific Manuscript database

    Application of poultry litter as a fertilizer source is a common practice in agriculture production. However, potential water quality concerns as a result of over application of poultry litter has risen as a major environmental issue in states with substantial poultry production. Fundamental to the ...

  2. Temperatures below leaf litter during winter prescribed burns: implications for litter-roosting bats

    Treesearch

    Roger W. Perry; Virginia L. McDaniel

    2015-01-01

    Some bat species, including eastern red bats (Lasiurus borealis), roost for short periods beneath leaf litter on the forest floor during winter in the south-eastern USA, a region subjected to frequent fire. The variability in fuel consumption, the heterogeneous nature of burns, and the effects of litter and duff moisture on forest-floor...

  3. Watching eyes on potential litter can reduce littering: evidence from two field experiments.

    PubMed

    Bateson, Melissa; Robinson, Rebecca; Abayomi-Cole, Tim; Greenlees, Josh; O'Connor, Abby; Nettle, Daniel

    2015-01-01

    Littering constitutes a major societal problem, and any simple intervention that reduces its prevalence would be widely beneficial. In previous research, we have found that displaying images of watching eyes in the environment makes people less likely to litter. Here, we investigate whether the watching eyes images can be transferred onto the potential items of litter themselves. In two field experiments on a university campus, we created an opportunity to litter by attaching leaflets that either did or did not feature an image of watching eyes to parked bicycles. In both experiments, the watching eyes leaflets were substantially less likely to be littered than control leaflets (odds ratios 0.22-0.32). We also found that people were less likely to litter when there other people in the immediate vicinity than when there were not (odds ratios 0.04-0.25) and, in one experiment but not the other, that eye leaflets only reduced littering when there no other people in the immediate vicinity. We suggest that designing cues of observation into packaging could be a simple but fruitful strategy for reducing littering.

  4. Watching eyes on potential litter can reduce littering: evidence from two field experiments

    PubMed Central

    Bateson, Melissa; Robinson, Rebecca; Abayomi-Cole, Tim; Greenlees, Josh; O’Connor, Abby

    2015-01-01

    Littering constitutes a major societal problem, and any simple intervention that reduces its prevalence would be widely beneficial. In previous research, we have found that displaying images of watching eyes in the environment makes people less likely to litter. Here, we investigate whether the watching eyes images can be transferred onto the potential items of litter themselves. In two field experiments on a university campus, we created an opportunity to litter by attaching leaflets that either did or did not feature an image of watching eyes to parked bicycles. In both experiments, the watching eyes leaflets were substantially less likely to be littered than control leaflets (odds ratios 0.22–0.32). We also found that people were less likely to litter when there other people in the immediate vicinity than when there were not (odds ratios 0.04–0.25) and, in one experiment but not the other, that eye leaflets only reduced littering when there no other people in the immediate vicinity. We suggest that designing cues of observation into packaging could be a simple but fruitful strategy for reducing littering. PMID:26644979

  5. Potential energy expenditure by litter-roosting bats associated with temperature under leaf litter during winter

    Treesearch

    Roger W. Perry

    2013-01-01

    In temperate portions of North America, some bats that remain active during winter undergo short periods of hibernation below leaf litter on the forest floor during episodes of below-freezing weather. These winter roosts may provide above-freezing conditions, but the thermal conditions under leaf litter are unclear. Further, little is known of the relationship between...

  6. The distribution of the Bururi Long-fingered Frog (Cardioglossa cyaneospila, family Arthroleptidae), a poorly known Albertine Rift endemic.

    PubMed

    Blackburn, David C; Boix, Christian; Greenbaum, Eli; Fabrezi, Marissa; Meirte, Danny; Plumptre, Andrew J; Stanley, Edward L

    2016-09-23

    The species diversity of the frog genus Cardioglossa (family Arthroleptidae) is concentrated in the Lower Guinean Forest Zone of Central Africa with most of the 19 species occurring in Cameroon and neighboring countries (Amiet 1972a,b; Blackburn 2008; Hirschfeld et al. 2015). These small leaf-litter frogs are typically found in primary or secondary forest, have shrill whistling calls, are characterized by a variety of color patterns, and lay terrestrial eggs that hatch and develop into elongate, stream-adapted tadpoles (Amiet 1972a,b, 1973; Rödel et al. 2001; Hirschfeld et al. 2012). One of the most poorly known species-the Bururi Long-fingered Frog Cardioglossa cyaneospila Laurent, 1950-is also among the most geographically peripheral to the rest of the species diversity. To date, it is known only from two locations in Burundi and four in eastern Democratic Republic of Congo, regions in which armed conflicts have long hampered scientific research. In this short contribution, we (1) document both new and long unpublished records of C. cyaneospila, associate these with known museum records, and extend its geographic range, (2) highlight fruitful areas for future field surveys based on predicting an environmental envelope for this species, and (3) summarize what little is known of its natural history.

  7. Lignin degradation during plant litter photodegradation

    NASA Astrophysics Data System (ADS)

    Lin, Y.; King, J. Y.

    2014-12-01

    Lignin is the second most abundant compound, after cellulose, synthesized by plants. Numerous studies have demonstrated that initial lignin concentration is negatively correlated with litter decomposition rate under both laboratory and field conditions. Thus lignin is commonly considered to be a "recalcitrant" compound during litter decomposition. However, lignin can also serve as a radiation-absorbing compound during photodegradation, the process through which solar radiation breaks down organic matter. Here, we synthesize recent studies concerning lignin degradation during litter photodegradation and report results from our study on how photodegradation changes lignin chemistry at a molecular scale. Recent field studies have found that litter with high initial lignin concentration does not necessarily exhibit high mass loss during photodegradation. A meta-analysis (King et al. 2012) even found a weak negative correlation between initial lignin concentration and photodegradation rate. Contradicting results have been reported with regard to the change in lignin concentration during photodegradation. Some studies have found significant loss of lignin during photodegradation, while others have not. In most studies, loss of lignin only accounts for a small proportion of the overall mass loss. Using NMR spectroscopy, we found significant loss of lignin structural units containing beta-aryl ether linkages during photodegradation of a common grass litter, Bromus diandrus, even though conventional forage fiber analysis did not reveal changes in lignin concentration. Both our NMR and fiber analyses supported the idea that photodegradation induced loss of hemicellulose, which was mainly responsible for the litter mass loss during photodegradation. Our results suggest that photodegradation induces degradation, but not necessarily complete breakdown, of lignin structures and consequently exposes hemicellulose and cellulose to microbial decomposition. We conclude that lignin

  8. Unmasking Rana okinavana Boettger, 1895 from the Ryukyus, Japan (Amphibia: Anura: Ranidae).

    PubMed

    Matsui, Masafumi

    2007-02-01

    Examination of the lectotype and a paralectotype of Rana okinavana Boettger, 1895 revealed that the species is not a brown frog of the subgenus Rana, occurring in the middle group of the Ryukyu Archipelago, but is identical with a frog of the subgenus Nidirana from the southern group of the Archipelago and Taiwan, now called R. psaltes Kuramoto, 1985. The type locality of R. okinavana given in the original description, Okinawa of the middle Ryukyus, is highly doubtful and should be somewhere in the Yaeyama Islands of the southern Ryukyus. The name R. psaltes is relegated to a subjective junior synonym of R. okinavana Boettger, 1895, while the brown frog of the subgenus Rana from the northern Ryukyus requires a replacement name.

  9. Visual mate choice in poison frogs.

    PubMed

    Summers, K; Symula, R; Clough, M; Cronin, T

    1999-11-07

    We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange and green) from two different island populations (Nancy Key and Pope Island) with object frogs (one of each morph) under glass at one end of a terrarium. Recorded calls were played simultaneously from behind both object frogs. The experiments were carried out under two light regimes: (i) white light, and (ii) relatively monochromatic filtered blue light. Subject females from each population displayed a significant preference for their own morph under white light, but not under blue light. These results indicate that female D. pumilio use visual cues in mate choice, and suggest that colour may be the visual cue they use.

  10. FROGS (Friends of Granites) Report, summer 1988

    NASA Astrophysics Data System (ADS)

    DeYoreo, J. J.; Wickham, Stephen M.; Miller, Calvin

    This is the second Eos-published FROGS Report. Our purpose is to disseminate information and stimulate thinking concerning felsic magmatism in general and granitoids in particular. We intend to publish semiannually information about events and publications that are relevant to the study of felsic rocks, brief updates on research being done by granitoid researchers, and commentaries on important new and/or controversial themes. FROGS Reports is critically dependent upon response by those with an interest in research on felsic rocks. Please keep me (Calvin Miller, 6028B, Vanderbilt Univ., Nashville TN 37235) informed about upcoming or recent conferences, major publications, etc. Also, send me your suggestions for topics for (and/or volunteer to write) pertinent commentaries for FROGS Reports.

  11. Frog skin epithelium: electrolyte transport and chytridiomycosis

    PubMed Central

    Campbell, Craig R.; Voyles, Jamie; Cook, David I.; Dinudom, Anuwat

    2012-01-01

    One unique physiological characteristic of frogs is that their main route for intake of water is across the skin. In these animals, the skin acts in concert with the kidney and urinary bladder to maintain electrolyte homeostasis. Water absorption across the skin is driven by the osmotic gradient that develops as a consequence of solute transport. Our recent study demonstrated that chytridiomycosis, an infection of amphibian skin by the fungal pathogen, Batrachochytrium dendrobatidis, inhibits epithelial Na+ channels, attenuating Na+ absorption through the skin. In frogs that become severely affected by this fungus, systemic depletion of Na+, K+ and Cl− is thought to cause deterioration of cardiac electrical function, leading to cardiac arrest. Here we review the ion transport mechanisms of frog skin, and discuss the effect of chytridiomycosis on these mechanisms. PMID:22182598

  12. The biology of some intraerythrocytic parasites of fishes, amphibia and reptiles.

    PubMed

    Davies, A J; Johnston, M R

    2000-01-01

    Fishes, amphibia and reptiles, the ectothermic vertebrates, are hosts for a variety of intraerythrocytic parasites including protists, prokaryotes, viruses and structures of uncertain status. These parasites may experience host temperature fluctuations, host reproductive strategies, population genetics, host habitat and migratory behaviour quite unlike those of endothermic hosts. Few blood infections of fishes, amphibia and reptiles have proven pathogenicity, in contrast to the many intraerythrocytic parasites of mammals and some birds which harm their hosts. Although not given the attention afforded to intraerythrocytic parasites of endotherms, those of ectotherms have been studied for more than a century. This review reports on the diversity, general biology and phylogeny of intraerythrocytic parasites of ectotherms. The existence of taxonomic confusion is emphasized and the main taxonomic features of most of the 23 better characterized genera, particularly the kinetoplastid and apicomplexan protists, are summarized. Transmission of protistan infections of aquatic ectotherms is also discussed. Leeches can transfer sporozoties or merozoites to the vertebrate host during feeding. Dormant sporozoites of Lankesterella may permit transmission of species of this genus between vertebrates by predation. The fish haemogregarine, Haemogregarina bigemina, probably has gnathiid isopods, rather than leeches, as its definitive hosts. Hepatozoon spp. in aquatic hosts, and Progarnia of caiman, may also use invertebrate hosts other than leeches. Protistan infections of terrestrial or semi-terrestrial hosts are transmitted by a variety of arthropods, or, in some cases, leeches, contaminated paratenic hosts, or sporocysts free in water. Transfer of protists between vertebrates by predation and congenitally may also occur. The biology of the host cells of these infections, the red blood cells of ectotherm vertebrates, is summarized and compared with that of mammalian erythrocytes

  13. FROGS (Friends of Granites) Report, Fall 1987

    NASA Astrophysics Data System (ADS)

    Miller, Calvin F.; Lawford, J.

    This is the first official FROGS report in Eos. Our purpose is to disseminate information about the status of felsic igneous petrology, providing information and opinions about research, ideas, and problems that relate especially to granitoids but also, clearly, to felsic volcanic rocks. A major goal has been to bridge the gap between field-based and experimental approaches. For several years, FROGS reports have existed as occasional informal newsletters, but we feel that our purposes will be better served by semiannual publication as a section of the VGP News. A briefer companion report will also be published in The Lattice, the newsletter of the Mineralogical Society of America.

  14. Biological and climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments

    NASA Astrophysics Data System (ADS)

    Portillo-Estrada, M.; Pihlatie, M.; Korhonen, J. F. J.; Levula, J.; Frumau, A. K. F.; Ibrom, A.; Lembrechts, J. J.; Morillas, L.; Horváth, L.; Jones, S. K.; Niinemets, Ü.

    2015-11-01

    Projection of carbon and nitrogen cycles to future climates is associated with large uncertainties, in particular due to uncertainties how changes in climate alter soil turnover, including litter decomposition. In addition, future conditions are expected to result in changes in vegetation composition, and accordingly in litter type and quality, but it is unclear how such changes could potentially alter litter decomposition. Litter transplantation experiments were carried out across 6 European sites (4 forest and 2 grasslands) spanning a large geographical and climatic gradient (5.6-11.4 °C in annual temperature 511-878 mm in precipitation) to gain insight into biological (litter origin and type, soil type) and climatic controls on litter decomposition. The decomposition k rates were overall higher in warmer and wetter sites than in colder and drier sites, and positively correlated to the litter total specific leaf area. Also, litter N content increased as less litter mass remained and decay went further. Surprisingly, this study demonstrates that climatic controls on litter decomposition are quantitatively more important than species, litter origin and soil type. Cumulative climatic variables, precipitation and air temperature (ignoring days with air temperatures below 0 °C), were appropriate to predict the litter remaining mass during decomposition (Mr). And Mr and cumulative air temperature were found to be the best predictors for litter carbon and nitrogen remaining during decomposition. We concluded with an equation for predicting the decomposition k rate by using mean annual air temperature and litter total specific leaf area.

  15. VOC Emissions From Decomposing Leaf Litter

    NASA Astrophysics Data System (ADS)

    Brown, E. M.; Wilkinson, M. J.; Fierer, N.; Monson, R. K.

    2007-12-01

    The emission of VOCs from the biosphere has a profound effect on the oxidative capacity of the troposphere. Most studies of the flux of reactive carbon from the biosphere have focused on BVOC emissions at leaf and canopy scales with relatively few studies investigating BVOC emissions from soils. Here we present results describing the emissions of a suite of BVOCs from different litter types under different levels of nitrogen availability. To investigate these effects, three biochemically distinct litter types (Deschampsia sp., Acomostylis sp., and Rhododendron sp.) were coarsely ground and incubated in the dark for two months under different nitrogen regimes at optimal conditions for microbial activity. We used proton transfer reaction mass spectrometry and an infrared gas analyzer (IRGA) to monitor BVOC emissions and CO2 production rates throughout the course of the investigation. When different leaf litter types decomposed, they released distinctly different types and quantities of VOCs. However, varying nitrogen availability caused the VOC signature from some litters to change dramatically. We suggest that decomposition of leaf litter could provide a substantive source of reactive carbon to the atmosphere at local and regional scales and hypothesize that nitrogen deposition may play a role in attenuating the release of some reactive species.

  16. Photodegradation of roxarsone in poultry litter leachates

    USGS Publications Warehouse

    Bednar, A.J.; Garbarino, J.R.; Ferrer, I.; Rutherford, D.W.; Wershaw, R. L.; Ranville, J.F.; Wildeman, T.R.

    2003-01-01

    Arsenic compounds have been used extensively in agriculture in the US for applications ranging from cotton herbicides to animal feed supplements. Roxarsone (3-nitro-4-hydroxyphenylarsonic acid), in particular, is used widely in poultry production to control coccidial intestinal parasites. It is excreted unchanged in the manure and introduced into the environment when litter is applied to farmland as fertilizer. Although the toxicity of roxarsone is less than that of inorganic arsenic, roxarsone can degrade, biotically and abiotically, to produce more toxic inorganic forms of arsenic, such as arsenite and arsenate. Experiments were conducted on aqueous litter leachates to test the stability of roxarsone under different conditions. Laboratory experiments have shown that arsenite can be cleaved photolytically from the roxarsone moiety at pH 4-8 and that the degradation rate increases with increasing pH. Furthermore, the rate of photodegradation increases with nitrate and natural organic matter concentration, reactants that are commonly found in poultry-litter-water leachates. Additional photochemical reactions rapidly oxidize the cleaved arsenite to arsenate. The formation of arsenate is not entirely undesirable, because it is less mobile in soil systems and less toxic than arsenite. A possible mechanism for the degradation of roxarsone in poultry litter leachates is proposed. The results suggest that poultry litter storage and field application practices could affect the degradation of roxarsone and subsequent mobilization of inorganic arsenic species. ?? 2002 Elsevier Science B.V. All rights reserved.

  17. Pseudacris triseriata (western chorus frog) and Rana sylvatica (wood frog) chytridiomycosis

    USGS Publications Warehouse

    Rittman, S.E.; Muths, E.; Green, D.E.

    2003-01-01

    The chytrid fungus Batrachochytrium dendrobatidis is a known pathogen of anuran amphibians, and has been correlated with amphibian die-offs worldwide (Daszak et. al. 1999. Emerging Infectious Diseases 5:735-748). In Colorado, B. dendrobatidis has infected Boreal toads (Bufo boreas) (Muths et. al., in review) and has been identified on museum specimens of northern leopard frogs (Rana pipiens) (Carey et. al. 1999. Develop. Comp. Immunol. 23:459-472). We report the first verified case of chytrid fungus in chorus frogs (Pseudacris triseriata) and wood frogs (Rana sylvatica) in the United States. We collected seven P. triseriata, and two adult and two juvenile R. sylvatica in the Kawuneeche Valley in Rocky Mountain National Park (RMNP) during June 2001. These animals were submitted to the National Wildlife Health Center (NWHC) as part of an amphibian health evaluation in RMNP. Chorus frogs were shipped in one container. Wood frog adults and juveniles were shipped in two separate containers. Histological examinations of all chorus frogs and 3 of 4 wood frogs were positive for chytrid fungus infection. The fourth (adult) wood frog was too decomposed for meaningful histology. Histological findings consisted of multifocally mild to diffusely severe infections of the epidermis of the ventrum and hindlimb digital skin. Chytrid thalli were confined to the thickened epidermis (hyperkeratosis), were spherical to oval, and occasional thalli contained characteristic discharge pores or zoospores (Green and Kagarise Sherman 1999. J. Herpetol 35:92-103; Fellers et al. 2001. Copeia 2001:945-953). We cannot confirm that all specimens carried the fungus at collection, because infection may have spread from one individual to all other individuals in each container during transport. Further sampling of amphibians in Kawuneeche Valley is warranted to determine the rate of infection and mortality in these populations.

  18. Natural zeolites in diet or litter of broilers.

    PubMed

    Schneider, A F; Almeida, D S De; Yuri, F M; Zimmermann, O F; Gerber, M W; Gewehr, C E

    2016-04-01

    This study aims to analyse the influence of adding natural zeolites (clinoptilolite) to the diet or litter of broilers and their effects on growth performance, carcass yield and litter quality. Three consecutive flocks of broilers were raised on the same sawdust litter, from d 1 to d 42 of age, and distributed in three treatments (control with no added zeolites, addition of 5 g/kg zeolite to diet and addition of 100 g/kg zeolites to litter). The addition of zeolites to the diet or litter did not affect growth performance or carcass yield. The addition of zeolites to the diet did not influence moisture content of the litter, ammonia volatilisation was reduced only in the first flock and pH of litter was reduced in the second and third flock. However, the addition of zeolites to the litter reduced moisture content, litter pH and ammonia volatilisation in all flocks analysed. The addition of 5 g/kg zeolite to the diet in three consecutive flocks was not effective in maintaining litter quality, whereas the addition of 100 g/kg natural zeolites to sawdust litter reduced litter moisture and ammonia volatilisation in three consecutive flocks raised on the same litter.

  19. Individualistic Population Responses of Five Frog Species in Two Changing Tropical Environments over Time

    PubMed Central

    Ryan, Mason J.; Fuller, Michael M.; Scott, Norman J.; Cook, Joseph A.; Poe, Steven; Willink, Beatriz; Chaves, Gerardo; Bolaños, Federico

    2014-01-01

    Roughly 40% of amphibian species are in decline with habitat loss, disease, and climate change being the most cited threats. Heterogeneity of extrinsic (e.g. climate) and intrinsic (e.g. local adaptations) factors across a species’ range should influence population response to climate change and other threats. Here we examine relative detectability changes for five direct-developing leaf litter frogs between 42-year sampling periods at one Lowland Tropical Forest site (51 m.a.s.l.) and one Premontane Wet Forest site (1100 m.a.s.l.) in southwest Costa Rica. We identify individualistic changes in relative detectability among populations between sampling periods at different elevations. Both common and rare species showed site-specific declines, and no species exhibited significant declines at both sites. Detection changes are correlated with changes in temperature, dry season rainfall, and leaf litter depth since1969. Our study species share Least Concern conservation status, life history traits, and close phylogenetic relationship, yet their populations changed individualistically both within and among species. These results counter current views of the uniformity or predictability of amphibian decline response and suggest additional complexity for conservation decisions. PMID:24878504

  20. Control of climate and litter quality on leaf litter decomposition in different climatic zones.

    PubMed

    Zhang, Xinyue; Wang, Wei

    2015-09-01

    Climate and initial litter quality are the major factors influencing decomposition rates on large scales. We established a comprehensive database of terrestrial leaf litter decomposition, including 785 datasets, to examine the relationship between climate and litter quality and evaluate the factors controlling decomposition on a global scale, the arid and semi-arid (AS) zone, the humid middle and humid low (HL) latitude zones. Initial litter nitrogen (N) and phosphorus (P) concentration only increased with mean annual temperature (MAT) in the AS zone and decreased with mean annual precipitation (MAP) in the HL zone. Compared with nutrient content, MAT imposed less effect on initial litter lignin content than MAP. MAT were the most important decomposition driving factors on a global scale as well as in different climatic zones. MAP only significantly affected decomposition constants in AS zone. Although litter quality parameters also showed significant influence on decomposition, their importance was less than the climatic factors. Besides, different litter quality parameters exerted significant influence on decomposition in different climatic zones. Our results emphasized that climate consistently exerted important effects on decomposition constants across different climatic zones.

  1. Do all frogs swim alike? The effect of ecological specialization on swimming kinematics in frogs.

    PubMed

    Robovska-Havelkova, Pavla; Aerts, Peter; Rocek, Zbynek; Prikryl, Tomas; Fabre, Anne-Claire; Herrel, Anthony

    2014-10-15

    Frog locomotion has attracted wide scientific interest because of the unusual and derived morphology of the frog pelvic girdle and hind limb. Previous authors have suggested that the design of the frog locomotor system evolved towards a specialized jumping morphology early in the radiation of the group. However, data on locomotion in frogs are biased towards a few groups and most of the ecological and functional diversity remains unexplored. Here, we examine the kinematics of swimming in eight species of frog with different ecologies. We use cineradiography to quantify movements of skeletal elements from the entire appendicular skeleton. Our results show that species with different ecologies do differ in the kinematics of swimming, with the speed of limb extension and especially the kinematics of the midfoot being different. Our results moreover suggest that this is not a phylogenetic effect because species from different clades with similar ecologies converge on the same swimming kinematics. We conclude that it is important to analyze frog locomotion in a broader ecological and evolutionary context if one is to understand the evolutionary origins of this behavior.

  2. A new species of Mesocoelium (Digenea: Mesocoeliidae) found in Rhinella marina (Amphibia: Bufonidae) from Brazilian Amazonia.

    PubMed

    Gomes, Tássia F F; Melo, Francisco T V; Giese, Elane G; Furtado, Adriano P; Gonçalves, Evonnildo C; Santos, Jeannie N

    2013-04-01

    Mesocoelium lanfrediae sp. nov. (Digenea: Mesocoeliidae) inhabits the small intestine of Rhinella marina (Amphibia: Bufonidae) and is described here, with illustrations provided by light, scanning electron microscopy and molecular approachs. M. lanfrediae sp. nov. presents the typical characteristics of the genus, but is morphometrically and morphologically different from the species described previously. The main diagnostic characteristics of M. lanfrediae sp. nov. are (i) seven pairs of regularly-distributed spherical papillae on the oral sucker, (ii) ventral sucker outlined by four pairs of papillae distributed in a uniform pattern and interspersed with numerous spines, which are larger at the posterior margin and (iii) small, rounded tegumentary papillae around the opening of the oral sucker, which are morphologically different from those of the oral sucker itself, some of which are randomly disposed in the ventrolateral tegumentary region of the anterior third of the body. Addionally, based on SSU rDNA, a phylogenetic analysis including Brachycoeliidae and Mesocoeliidae taxa available on GenBank established the close relationship between M. lanfrediae sp. nov. and Mesocoelium sp.

  3. A new species of Mesocoelium (Digenea: Mesocoeliidae) found in Rhinella marina (Amphibia: Bufonidae) from Brazilian Amazonia

    PubMed Central

    Gomes, Tássia FF; Melo, Francisco TV; Giese, Elane G; Furtado, Adriano P; Gonçalves, Evonnildo C; Santos, Jeannie N

    2013-01-01

    Mesocoelium lanfrediaesp. nov. (Digenea: Mesocoeliidae) inhabits the small intestine of Rhinella marina (Amphibia: Bufonidae) and is described here, with illustrations provided by light, scanning electron microscopy and molecular approachs. M. lanfrediae sp. nov. presents the typical characteristics of the genus, but is morphometrically and morphologically different from the species described previously. The main diagnostic characteristics of M. lanfrediae sp. nov. are (i) seven pairs of regularly-distributed spherical papillae on the oral sucker, (ii) ventral sucker outlined by four pairs of papillae distributed in a uniform pattern and interspersed with numerous spines, which are larger at the posterior margin and (iii) small, rounded tegumentary papillae around the opening of the oral sucker, which are morphologically different from those of the oral sucker itself, some of which are randomly disposed in the ventrolateral tegumentary region of the anterior third of the body. Addionally, based on SSU rDNA, a phylogenetic analysis including Brachycoeliidae and Mesocoeliidae taxa available on GenBank established the close relationship between M. lanfrediae sp. nov. and Mesocoelium sp. PMID:23579798

  4. The origin of litter chemical complexity during decomposition.

    PubMed

    Wickings, Kyle; Grandy, A Stuart; Reed, Sasha C; Cleveland, Cory C

    2012-10-01

    The chemical complexity of decomposing plant litter is a central feature shaping the terrestrial carbon (C) cycle, but explanations of the origin of this complexity remain contentious. Here, we ask: How does litter chemistry change during decomposition, and what roles do decomposers play in these changes? During a long-term (730 days) litter decomposition experiment, we tracked concurrent changes in decomposer community structure and function and litter chemistry using high-resolution molecular techniques. Contrary to the current paradigm, we found that the chemistry of different litter types diverged, rather than converged, during decomposition due to the activities of decomposers. Furthermore, the same litter type exposed to different decomposer communities exhibited striking differences in chemistry, even after > 90% mass loss. Our results show that during decomposition, decomposer community characteristics regulate changes in litter chemistry, which could influence the functionality of litter-derived soil organic matter (SOM) and the turnover and stabilisation of soil C.

  5. Return of the Tarahumara frog to Arizona

    Treesearch

    James C. Rorabaugh; Stephen F. Hale; Michael J. Sredl; Craig Ivanyi

    2005-01-01

    The last wild Tarahumara frog (Rana tarahumarae) in Arizona was found dead in Big Casa Blanca Canyon, Santa Rita Mountains, in May 1983. However, the species is still well represented in the majority of its range in the northern Sierra Madre Occidental and adjacent Sky Islands of Sonora and Chihuahua. Plans to re-establish R. tarahumarae...

  6. Frog egg growth, experiment S003

    NASA Technical Reports Server (NTRS)

    Young, R. S.; Tremor, J. W.

    1971-01-01

    The objective of experiment was to determine the effect of weightlessness on the ability of a fertilized frog egg to divide normally and to differentiate and form a normal embryo. This experiment was first attempted on the Gemini 8 mission and was completed only partially because of the early termination of that mission.

  7. Frogs report: Friends of Granite, Winter 1990

    NASA Astrophysics Data System (ADS)

    FROGS reports present information on current research relevant to felsic magmatism, including commentaries on problems of current interest. Please contact Calvin Miller (Geology, 6028B, Vanderbilt University, Nashville, TN 37235, tel. 615-322-2986) about your own research, conferences, and ideas for stimulating commentaries.

  8. Hyperspectral analysis of columbia spotted frog habitat

    USGS Publications Warehouse

    Shive, J.P.; Pilliod, D.S.; Peterson, C.R.

    2010-01-01

    Wildlife managers increasingly are using remotely sensed imagery to improve habitat delineations and sampling strategies. Advances in remote sensing technology, such as hyperspectral imagery, provide more information than previously was available with multispectral sensors. We evaluated accuracy of high-resolution hyperspectral image classifications to identify wetlands and wetland habitat features important for Columbia spotted frogs (Rana luteiventris) and compared the results to multispectral image classification and United States Geological Survey topographic maps. The study area spanned 3 lake basins in the Salmon River Mountains, Idaho, USA. Hyperspectral data were collected with an airborne sensor on 30 June 2002 and on 8 July 2006. A 12-year comprehensive ground survey of the study area for Columbia spotted frog reproduction served as validation for image classifications. Hyperspectral image classification accuracy of wetlands was high, with a producer's accuracy of 96 (44 wetlands) correctly classified with the 2002 data and 89 (41 wetlands) correctly classified with the 2006 data. We applied habitat-based rules to delineate breeding habitat from other wetlands, and successfully predicted 74 (14 wetlands) of known breeding wetlands for the Columbia spotted frog. Emergent sedge microhabitat classification showed promise for directly predicting Columbia spotted frog egg mass locations within a wetland by correctly identifying 72 (23 of 32) of known locations. Our study indicates hyperspectral imagery can be an effective tool for mapping spotted frog breeding habitat in the selected mountain basins. We conclude that this technique has potential for improving site selection for inventory and monitoring programs conducted across similar wetland habitat and can be a useful tool for delineating wildlife habitats. ?? 2010 The Wildlife Society.

  9. Water quality benefits of subsurface-banded poultry litter

    USDA-ARS?s Scientific Manuscript database

    Broiler chicken production is an important industry in Alabama and several other states. Broiler litter is commonly used as a fertilizer on pastures and cropland. This litter has commonly been land-applied near the broiler houses and this has resulted in long-term repeated application of litter to...

  10. Litter decay rates are determined by lignin chemistry

    Treesearch

    Jennifer M. Talbot; Daniel J. Yelle; James Nowick; Kathleen K. Treseder

    2011-01-01

    Litter decay rates are often correlated with the initial lignin:N or lignin:cellulose content of litter, suggesting that interactions between lignin and more labile compounds are important controls over litter decomposition. The chemical composition of lignin may influence these interactions, if lignin physically or chemically protects labile components from microbial...

  11. Long-term litter decomposition controlled by manganese redox cycling.

    PubMed

    Keiluweit, Marco; Nico, Peter; Harmon, Mark E; Mao, Jingdong; Pett-Ridge, Jennifer; Kleber, Markus

    2015-09-22

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn(2+) provided by fresh plant litter to produce oxidative Mn(3+) species at sites of active decay, with Mn eventually accumulating as insoluble Mn(3+/4+) oxides. Formation of reactive Mn(3+) species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn(3+)-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn(3+) species in the litter layer. This observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant-soil system may have a profound impact on litter decomposition rates.

  12. Subsurface Banded Broiler Litter Improves Cotton Yield and Quality

    USDA-ARS?s Scientific Manuscript database

    Broiler litter is typically land-applied as a fertilizer by surface broadcasting, a practice that results in volatilization loss of N as NH3. This loss may be drastically reduced or eliminated by the use of a newly developed precision litter implement designed to apply the litter in bands just belo...

  13. Separating duff and litter for improved mass and carbon estimates

    Treesearch

    David Chojnacky; Michael Amacher; Michael Gavazzi

    2009-01-01

    Mass and carbon load estimates, such as those from forest soil organic matter (duff and litter), inform forestry decisions. The US Forest Inventory and Analysis (FIA) Program systematically collects data nationwide: a down woody material protocol specifies discrete duff and litter depth measurements, and a soils protocol specifies mass and carbon of duff and litter...

  14. The Evaluation of Litter Behavior Modification in a River Environment.

    ERIC Educational Resources Information Center

    Wagstaff, Mark C.; Wilson, Beth E.

    1988-01-01

    Behavior modification techniques were evaluated by observing litter collection behavior of commercial rafting groups. The number of litter pieces retrieved by treatment and control groups was significantly different. Results support the idea that verbal appeal and role modeling can be effective litter control techniques. (Author/CW)

  15. Nutrition of cotton fertilized with poultry litter versus ammonium nitrate

    USDA-ARS?s Scientific Manuscript database

    Poultry litter has proven to be an effective fertilizer for cotton in the upland soils of the southeastern US. Fertilizing with poultry litter often results in better lint yield than fertilizing with single-nutrient synthetic fertilizers. This superiority of litter to synthetic fertilizers for cot...

  16. Larch Litter Removal Has No Significant Effect On Runoff

    Treesearch

    Richard S. Startz; David N. Tolsted

    1974-01-01

    Runoff was measured on paired litter-removed, litter-left plots in an 11-year-old European larch plantation. On five of the six pairs of plots, the plot with the litter left intact yielded more runoff. however, the differences were neither statistically nor hydrologically significant.

  17. Long-term litter decomposition controlled by manganese redox cycling

    PubMed Central

    Keiluweit, Marco; Nico, Peter; Harmon, Mark E.; Mao, Jingdong; Pett-Ridge, Jennifer; Kleber, Markus

    2015-01-01

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of litter was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn2+ provided by fresh plant litter to produce oxidative Mn3+ species at sites of active decay, with Mn eventually accumulating as insoluble Mn3+/4+ oxides. Formation of reactive Mn3+ species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn3+-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn3+ species in the litter layer. This observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant–soil system may have a profound impact on litter decomposition rates. PMID:26372954

  18. Chromosome banding in Amphibia. XXVI. Coexistence of homomorphic XY sex chromosomes and a derived Y-autosome translocation in Eleutherodactylus maussi (Anura, Leptodactylidae).

    PubMed

    Schmid, M; Feichtinger, W; Steinlein, C; Haaf, T; Schartl, M; Visbal García, R; Manzanilla Pupo, J; Fernández Badillo, A

    2002-01-01

    A 15-year cytogenetic survey on one population of the leaf litter frog Eleutherodactylus maussi in northern Venezuela confirmed the existence of multiple XXAA male symbol /XAA(Y) female symbol sex chromosomes which originated by a centric (Robertsonian) fusion between the original Y chromosome and an autosome. 95% of the male individuals in this population are carriers of this Y-autosome fusion. In male meiosis the XAA(Y) sex chromosomes pair in the expected trivalent configuration. In the same population, 5% of the male animals still possess the original, free XY sex chromosomes. In a second population of E. maussi analyzed, all male specimens are characterized by these ancestral XY chromosomes which form normal bivalents in meiosis. E. maussi apparently represents the first vertebrate species discovered in which a derived Y-autosome fusion still coexists with the ancestral free XY sex chromosomes. The free XY sex chromosomes, as well as the multiple XA(Y) sex chromosomes are still in a very primitive (homomorphic) stage of differentiation. With no banding technique applied it is possible to distinguish the Y from the X. DNA flow cytometric measurements show that the genome of E. maussi is among the largest in the anuran family Leptodactylidae. The present study also supplies further data on differential chromosome banding and fluorescence in situ hybridization experiments in this amphibian species.

  19. The Effect of Litter Position on Ultraviolet Photodegradation of Standing Dead Litter

    NASA Astrophysics Data System (ADS)

    Lin, Y.; King, J. Y.

    2012-12-01

    In dryland ecosystems, models incorporating only biotic mechanisms usually underestimate the decay rate of plant litter. Photodegradation, an abiotic process through which solar radiation breaks down organic matter, has recently been proposed as an important pathway of litter decomposition in dryland ecosystems, accounting for as much as 25 to 60% of mass loss. However, it remains unclear what factors control the relative importance of photodegradation and biotic decomposition. It is hypothesized that this balance is affected by the location of litter within the litter layer (or thatch): in upper layers of thatch, photodegradation is significant because litter is exposed to sunlight; in lower layers where litter is strongly shaded, photodegradation is negligible compared to biotic decomposition. In August 2011, a field experiment was initiated at the University of California's Sedgwick Reserve, Santa Ynez, CA, in order to understand how ultraviolet (UV) radiation and litter position within the thatch affect litter decomposition. Two levels of UV radiation (280-400 nm) are achieved by screens: "UV-Pass" (transmitting > 81% of UV radiation) and "UV-Block" (transmitting < 8% of UV radiation). Litterbags were placed either at the top or at the bottom of the thatch. Results after 9 months of field exposure show that at the top of the thatch, litter mass loss was 13% higher in UV-Pass than in UV-Block, suggesting the occurrence of UV photodegradation. Surprisingly, litter mass loss was 52% higher in UV-Pass at the bottom of the thatch, even though very limited UV radiation penetrated through the thatch (at least 10 cm thick). The relative humidity in the thatch was higher in UV-Pass than in UV-Block treatments, especially at night; thus it is speculated that the UV manipulation not only alters the incoming radiation spectrum but also affects microclimate, consequently changing biotic decomposition. At the bottom of the thatch, lignin concentration of plant litter was 19

  20. Evaluation of ammonia emissions from broiler litter

    USDA-ARS?s Scientific Manuscript database

    Ammonia emissions from poultry litter results in air pollution and can cause high levels of ammonia in poultry houses, which negatively impacts bird performance. The objectives of this study were to: (1) conduct a nitrogen (N) mass balance in broiler houses by measuring the N inputs (bedding, chick...

  1. Climate history shapes contemporary leaf litter decomposition

    Treesearch

    Michael S. Strickland; Ashley D. Keiser; Mark A. Bradford

    2015-01-01

    Litter decomposition is mediated by multiple variables, of which climate is expected to be a dominant factor at global scales. However, like other organisms, traits of decomposers and their communities are shaped not just by the contemporary climate but also their climate history. Whether or not this affects decomposition rates is underexplored. Here we source...

  2. Extension Leads Model City Litter Fight

    ERIC Educational Resources Information Center

    Magnuson, Doris

    1971-01-01

    A three-year war on litter is in effect in the Portland, Maine, area, as a result of the University of Maine's enlisting the county extension service to help the local Model Cities program clean up the inner city. Article details problems and progress in meeting the objectives. (PD)

  3. Litter Study: A School Research Project

    ERIC Educational Resources Information Center

    McCollum, Dannel

    1976-01-01

    Describes a project done to verify or dispute the breakdown in litter content proposed by Keep America Beautiful, Inc. (KAB). Decisions made relating to quantity of materials, area to be studied, and a complete description of the project are given. (EB)

  4. Extension Leads Model City Litter Fight

    ERIC Educational Resources Information Center

    Magnuson, Doris

    1971-01-01

    A three-year war on litter is in effect in the Portland, Maine, area, as a result of the University of Maine's enlisting the county extension service to help the local Model Cities program clean up the inner city. Article details problems and progress in meeting the objectives. (PD)

  5. Prospects for phosphorus recovery from poultry litter

    USDA-ARS?s Scientific Manuscript database

    Land disposal of poultry litter is an environmental concern in regions with intense poultry production because there is not enough land for crop utilization of its nutrients, especially phosphorus (P). This situation promotes soil P surplus and potential pollution of water resources. Although poultr...

  6. Utilization of poultry litter for pesticide bioremediation

    USDA-ARS?s Scientific Manuscript database

    Agricultural chemical products such as pesticides have been used to increase crop production, especially in undeveloped countries. Poultry litter, the combination of feces and bedding materials, has also been used as an alternative to improve soil quality for crop production. However, information re...

  7. Ecological restoration of litter in mined areas

    NASA Astrophysics Data System (ADS)

    Teresinha Gonçalves Bizuti, Denise; Nino Diniz, Najara; Schweizer, Daniella; de Marchi Soares, Thaís; Casagrande, José Carlos; Henrique Santin Brancalion, Pedro

    2016-04-01

    The success of ecological restoration projects depends on going monitoring of key ecological variables to determine if a desired trajectory has been established and, in the case of mining sites, nutrient cycling recovery plays an utmost importance. This study aimed to quantify and compare the annual litter production in native forests, and in restoration sites established in bauxite mines. We collected samples in 6 native forest remnants and 6 year-old restoration sites every month for a period of one year, in the city of Poços de Caldas/MG, SE Brazil. 120 wire collectors were used (0,6x0,6) and suspended 30cm above the soil surface. The material was dried until constant weight, weighed and fractionated in leaves, branches and reproductive material. The average annual litter production was 2,6 Mg ha-1 in native forests and 2,1 in forest in restoration sites, differing statistically. Litter production was higher in the rainy season, especially in September. Among the litter components, the largest contributor to total production was the fraction leaves, with 55,4% of the total dry weight of material collected, followed by reproductive material which contributed 24,5% and branches, with 20%. We conclude that the young areas in restoration process already restored important part, but still below the production observed in native areas.

  8. Converting Poultry Litter into Activated Carbon

    USDA-ARS?s Scientific Manuscript database

    Disposal of animal manure is one of the biggest problems facing agriculture today. Now new technology has been designed to covert manure into environmentally friendly and highly valued activated carbon. When pelletized and activated under specific conditions, the litter becomes a highly porous mat...

  9. Treating poultry litter with aluminum sulfate (alum)

    USDA-ARS?s Scientific Manuscript database

    This is a USDA/ARS factsheet on how to treat poultry litter with aluminum sulfate (alum) to reduce ammonia emissions. Over half of the nitrogen excreted from chickens is lost to the atmosphere as ammonia before the manure is removed from the poultry houses. Research has shown that additions of alu...

  10. The management of phosphorus in poultry litter

    USDA-ARS?s Scientific Manuscript database

    Poultry litter provides an important source of plant nutrients including nitrogen, phosphorus, potassium, calcium, magnesium and sulphur. The potential for phosphorus (P) surplus at the farm scale can increase when farming systems change from cropping to intensive poultry and animal production, as P...

  11. Critical litter moisture maximizes ammonia generation

    USDA-ARS?s Scientific Manuscript database

    The natural breakdown of litter (bedding material mixed with deposits of feces, feathers, spilled feed and water) generates ammonia in poultry houses. Good management practices can reduce ammonia concentrations in poultry houses. Findings from a recent publication indicate there is a critical litt...

  12. Poultry litter moisture management to reduce ammonia

    USDA-ARS?s Scientific Manuscript database

    Ammonia generation in poultry houses results from the natural breakdown of litter (bedding material mixed with deposits of feces, feathers, spilled feed and water). Good management practices can reduce ammonia concentrations in poultry houses. This factsheet relates findings from a recent publicat...

  13. The global stoichiometry of litter nitrogen mineralization

    Treesearch

    Stefano Manzoni; Robert B. Jackson; John A. Trofymow; Amilcare Porporato

    2008-01-01

    Plant residue decomposition and the nutrient release to the soil play a major role in global carbon and nutrient cycling. Although decomposition rates vary strongly with climate, nitrogen immobilization into litter and its release in mineral forms are mainly controlled by the initial chemical composition of the residues. We used a data set of ~2800 observations to show...

  14. The fate of nitrogen mineralized from leaf litter — Initial evidence from 15N-labeled litter

    Treesearch

    Kathryn B. Piatek

    2011-01-01

    Decomposition of leaf litter includes microbial immobilization of nitrogen (N), followed by N mineralization. The fate of N mineralized from leaf litter is unknown. I hypothesized that N mineralized from leaf litter will be re-immobilized into other forms of organic matter, including downed wood. This mechanism may retain N in some forests. To test this hypothesis, oak...

  15. Leaf litter decomposition in a southern Sonoran Desert ecosystem, northwestern Mexico: Effects of habitat and litter quality

    NASA Astrophysics Data System (ADS)

    Martínez-Yrízar, Angelina; Núñez, Silvia; Búrquez, Alberto

    2007-11-01

    Leaf litter decomposition of dominant woody perennial species in the three most common habitats of the southern Sonoran Desert was studied using the litter-bag method. Our objective was to assess the influence of litter quality on decomposition rates in three contrasting desert environments. The hypotheses were: (1) decomposition rates within the same litter type are faster in more mesic habitats, (2) decomposition rates are lower in higher lignin content or lower nutrient quality substrates, and (3) species-rich substrates enhance decomposition rates. For all litter types and habitats, a rapid loss of mass occurred during the summer rains at the start of the experiment, but total loss within the same litter type differed significantly among habitats. Decay rates were not higher in the more mesic habitat, but in the dry plains where solar irradiance and termite activity were highest. While termite activity was less important in the arroyos and absent in the hillsides habitats, proliferation of fungal mycelium in these sites was much higher than in the plains, suggesting that biotic and abiotic factors act both independently of litter richness. Lignin content seems to be an important factor controlling the loss of litter, because decay rates were inversely related to litter initial lignin content in all three habitats. Leaf litter diversity did not enhance rates of decomposition. The leaf litter mixture had k-values similar to the most recalcitrant monospecific litter in all three habitats, indicating a neutral or even antagonistic role of species-specific compounds in decomposition rates.

  16. Litter decomposition in southern Appalachian black locust and pine-hardwood stands: litter quality and nitrogen dynamics

    Treesearch

    David L. White; Bruce L. Haines

    1988-01-01

    The chemical quality of litter, through its interaction with macroclimate and the litter biota, largely regulates the rate of organic matter (OM) and nitrogen (N) turnover in the forest floor (Cromack 1973; Fogel and Cromack 1977; Meentemeyer 1978; Aber and Melillo 1982; Melillo et al. 1982). Litter quality is thought to be related to the N require-ment and...

  17. Fallout volume and litter type affect (137)Cs concentration difference in litter between forest and stream environments.

    PubMed

    Sakai, Masaru; Gomi, Takashi; Negishi, Junjiro N

    2016-11-01

    It is important to understand the changes in the (137)Cs concentration in litter through leaching when considering that (137)Cs is transferred from basal food resources to animals in forested streams. We found that the difference of (137)Cs activity concentration in litter between forest and stream was associated with both litter type and (137)Cs fallout volume around Fukushima, Japan. The (137)Cs activity concentrations in the litter of evergreen conifers tended to be greater than those in the litter of broad-leaved deciduous trees because of the absence of deciduous leaves during the fallout period in March 2011. Moreover, (137)Cs activity concentrations in forest litter were greater with respect to the (137)Cs fallout volume. The (137)Cs activity concentrations in stream litter were much lower than those in forest litter when those in forest litter were higher. The (137)Cs leaching patterns indicated that the differences in (137)Cs activity concentration between forest and stream litter could change with changes in both fallout volume and litter type. Because litter is an important basal food resource in the food webs of both forests and streams, the (137)Cs concentration gradient reflects to possible (137)Cs transfer from lower to higher trophic animals. Our findings will improve our understanding of the spatial heterogeneity and variability of (137)Cs concentrations in animals resident to the contaminated landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Water addition, evaporation and water holding capacity of poultry litter.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2015-12-15

    Litter moisture content has been related to ammonia, dust and odour emissions as well as bird health and welfare. Improved understanding of the water holding properties of poultry litter as well as water additions to litter and evaporation from litter will contribute to improved litter moisture management during the meat chicken grow-out. The purpose of this paper is to demonstrate how management and environmental conditions over the course of a grow-out affect the volume of water A) applied to litter, B) able to be stored in litter, and C) evaporated from litter on a daily basis. The same unit of measurement has been used to enable direct comparison-litres of water per square metre of poultry shed floor area, L/m(2), assuming a litter depth of 5cm. An equation was developed to estimate the amount of water added to litter from bird excretion and drinking spillage, which are sources of regular water application to the litter. Using this equation showed that water applied to litter from these sources changes over the course of a grow-out, and can be as much as 3.2L/m(2)/day. Over a 56day grow-out, the total quantity of water added to the litter was estimated to be 104L/m(2). Litter porosity, water holding capacity and water evaporation rates from litter were measured experimentally. Litter porosity decreased and water holding capacity increased over the course of a grow-out due to manure addition. Water evaporation rates at 25°C and 50% relative humidity ranged from 0.5 to 10L/m(2)/day. Evaporation rates increased with litter moisture content and air speed. Maintaining dry litter at the peak of a grow-out is likely to be challenging because evaporation rates from dry litter may be insufficient to remove the quantity of water added to the litter on a daily basis. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  19. An experimental analysis of anti-litter procedures1

    PubMed Central

    Burgess, Robert L.; Clark, Roger N.; Hendee, John C.

    1971-01-01

    This study evaluates the differential effectiveness of six different anti-litter procedures in two neighborhood theaters. The procedures used to encourage individuals in attendance to pick up litter and deposit it properly included: providing litterbags, providing litterbags with instructions to use them, providing extra trash cans, showing a special anti-litter film before the feature film, and providing incentives for the appropriate deposit of litter. In both theaters, the incentive procedures resulted in the removal of over 90% of all litter by the children in attendance, a figure far above that achieved by the other procedures investigated. PMID:16795289

  20. Post-Wildfire Sedimentation in Saguaro National Park, Rincon Mountain District, and Effects on Lowland Leopard Frog Habitat

    USGS Publications Warehouse

    Parker, John T.C.

    2006-01-01

    The Rincon Mountain District of Saguaro National Park occupies about 272 square kilometers of mountains, canyons, and alluvial fans in southeastern Arizona just east of Tucson. The park contains some of the last remaining habitat in the Tucson Basin of the lowland leopard frog that lives in the bedrock pools called tinajas in canyons at elevations between 850 and 1,800 meters. Those tinajas that contain water year-round are critical winter habitat for tadpoles, and the breeding success of the leopard frogs depends on these features. In recent years, many tinajas that previously had provided habitat for the leopard frogs have been buried beneath large volumes of coarse sandy gravel that resulted from severe, stand-replacing wildfires in the watersheds above them. The U. S. Geological Survey in cooperation with the National Park Service, conducted a study in 2004-06 to determine critical sediment-source areas, and the mechanisms of sediment delivery from hillslopes to stream channels to areas of leopard frog habitat and to estimate the increase in rates of sedimentation resulting from wildfires. Spatial data of watershed characteristics, as well as historical data, including photographs, monitoring surveys, precipitation and stream discharge records, were used in conjunction with field observations conducted between spring 2004 and fall 2005. The Helens II fire in 2003, the fifth largest wildfire to burn in the Rincon Mountains since 1989, offered an opportunity to observe mechanisms of sediment erosion, transport, and deposition in the immediate post-fire environment. Reduction of the forest canopy, understory vegetation, and organic litter on the ground surface in severe burn areas caused increased surface runoff in the Joaquin Canyon watershed that led to intensified erosion of hillslopes. An initial flush of fine material, mostly ash, was transported to lower channel reaches with the first significant precipitation event following the fire. Subsequently, the main

  1. Auditory Evoked Potentials from the Frog Eighth Nerve

    DTIC Science & Technology

    1989-09-01

    ACCESSION NO. Brooks AFB, TX 78235-5301 62202F 7757 01 85 11. TITLE (I nclude Security Classification) (U) Auditory Evoked Potentials from the Frog Eighth...identify by block number) S FIELD jGROUP SUB-GROUP F6 07 Auditory Evoked Potential Eighth Nerve Frog 06 10 19. ABSTRACT (Continue on reverse if necessary...and identify by block number) A method for recording evoked potentials from the eighth nerve of frogs using midline and lateral electrodes is described

  2. From frog integument to human skin: dermatological perspectives from frog skin biology.

    PubMed

    Haslam, Iain S; Roubos, Eric W; Mangoni, Maria Luisa; Yoshizato, Katsutoshi; Vaudry, Hubert; Kloepper, Jennifer E; Pattwell, David M; Maderson, Paul F A; Paus, Ralf

    2014-08-01

    For over a century, frogs have been studied across various scientific fields, including physiology, embryology, neuroscience, (neuro)endocrinology, ecology, genetics, behavioural science, evolution, drug development, and conservation biology. In some cases, frog skin has proven very successful as a research model, for example aiding in the study of ion transport through tight epithelia, where it has served as a model for the vertebrate distal renal tubule and mammalian epithelia. However, it has rarely been considered in comparative studies involving human skin. Yet, despite certain notable adaptations that have enabled frogs to survive in both aquatic and terrestrial environments, frog skin has many features in common with human skin. Here we present a comprehensive overview of frog (and toad) skin ontogeny, anatomy, cytology, neuroendocrinology and immunology, with special attention to its unique adaptations as well as to its similarities with the mammalian integument, including human skin. We hope to provide a valuable reference point and a source of inspiration for both amphibian investigators and mammalian researchers studying the structural and functional properties of the largest organ of the vertebrate body.

  3. Future increase in temperature more than decrease in litter quality can affect microbial litter decomposition in streams.

    PubMed

    Ferreira, Verónica; Chauvet, Eric

    2011-09-01

    The predicted increase in atmospheric CO(2) concentration for this century is expected to lead to increases in temperature and changes in litter quality that can affect small woodland streams, where water temperature is usually low and allochthonous organic matter constitutes the basis of the food web. We have assessed the individual and interactive effect of water temperature (5 and 10°C) and alder litter quality produced under ambient CO(2) levels (ambient litter) or under CO(2) concentrations predicted for 2050 (elevated litter) on litter decomposition and on fungal activity and assemblage structure. Litter decomposition rates and fungal respiration rates were significantly faster at 10 than at 5°C, but they were not affected by litter quality. Litter quality affected mycelial biomass accrual at 5 but not at 10°C, while increases in temperature stimulated biomass accrual on ambient but not on elevated litter. A similar pattern was observed for conidial production. All variables were stimulated on elevated litter at 10°C (future scenario) compared with ambient litter at 5°C (present scenario), but interactions between temperature and litter quality were additive. Temperature was the factor that most strongly affected the structure of aquatic hyphomycete assemblages. Our results indicate that if future increases in atmospheric CO(2) lead to only slight modifications in litter quality, the litter decomposition and fungal activities and community structure will be strongly controlled by increased water temperature. This may have serious consequences for aquatic systems as faster litter decomposition may lead to food depletion for higher trophic levels.

  4. The impact of alum addition on organic P transformations in poultry litter and litter-amended soil.

    PubMed

    Warren, Jason G; Penn, Chad J; McGrath, Joshua M; Sistani, Karamat

    2008-01-01

    Poultry litter treatment with alum (Al(2)(SO(4))(3) . 18H(2)O) lowers litter phosphorus (P) solubility and therefore can lower litter P release to runoff after land application. Lower P solubility in litter is generally attributed to aluminum-phosphate complex formation. However, recent studies suggest that alum additions to poultry litter may influence organic P mineralization. Therefore, alum-treated and untreated litters were incubated for 93 d to assess organic P transformations during simulated storage. A 62-d soil incubation was also conducted to determine the fate of incorporated litter organic P, which included alum-treated litter, untreated litter, KH(2)PO(4) applied at 60 mg P kg(-1) of soil, and an unamended control. Liquid-state (31)P nuclear magnetic resonance indicated that phytic acid was the only organic P compound present, accounting for 50 and 45% of the total P in untreated and alum-treated litters, respectively, before incubation and declined to 9 and 37% after 93 d of storage-simulating incubation. Sequential fractionation of litters showed that alum addition to litter transformed 30% of the organic P from the 1.0 mol L(-1) HCl to the 0.1 mol L(-1) NaOH extractable fraction and that both organic P fractions were more persistent in alum-treated litter compared with untreated litter. The soil incubation revealed that 0.1 mol L(-1) NaOH-extractable organic P was more recalcitrant after mixing than was the 1.0 mol L(-1) HCl-extractable organic P. Thus, adding alum to litter inhibits organic P mineralization during storage and promotes the formation of alkaline extractable organic P that sustains lower P solubility in the soil environment.

  5. Changes in litter near an aluminum reduction plant

    USGS Publications Warehouse

    Beyer, W.N.; Fleming, W.J.; Swineford, D.

    1987-01-01

    Litter was collected from eight sites at distances as far as 33 km from an AI reduction plant in western Tennessee. As a result of an accumulation of fine litter (< 4.75 mm) the weight of the litter per unit area was abnormally high at the two sites within 2 km of the plant. Compared to litter collected far from the plant, it had a lower fiber content, was more sapric, and was less acid. Fluoride emissions from the plant were suggested as the probable cause of litter changes. Concentrations of water-extractable and acid-extractable F- in the litter, the 0- to 5-cm soil layer, and the 5- to 15-cm soil layer were strongly correlated with distance from the plant. Total acid-extractable F- in the litter and upper 15 cm of soil was about 41 times as much at the closest site (700 mg/kg) as at the most distant sites (12 and 16 mg/kg). In a bioassay of litter from our study sites, woodlice (Porcellio scaber Latr.) had an abnormally high mortality in litter that contained 440 mg/kg or more of acid-extractable F-. However, when F- was added as NaF to litter, a significant increase in mortality was observed only in treatments exceeding 800 mg/kg. The decrease in the rate of decomposition of the litter might eventually induce a deficiency of soil macronutrients, but none was detected.

  6. The advertisement call and comments on the distribution of Eleutherodactylus bilineatus Bokermann, 1975, an endemic frog of Bahia State, Brazil (Amphibia, Anura)

    PubMed Central

    Dias, Iuri Ribeiro; de Mira-Mendes, Caio Vinicius; Souza-Costa, Carlos Augusto; Juncá, Flora Acuña; Solé, Mirco

    2017-01-01

    Abstract Advertisement calls can be used to aid solving taxonomic problems and understanding the evolution of certain groups. In this study, the advertisement call of Eleutherodactylus bilineatus is described. It is composed by two different notes with a total duration of 0.529–4.241 seconds and dominant frequency of 1.72–3.45 kHz. Additionally, new data is provided on the geographical distribution of Eleutherodactylus bilineatus and the most inland record for this species. PMID:28769692

  7. The advertisement call and comments on the distribution of Eleutherodactylus bilineatus Bokermann, 1975, an endemic frog of Bahia State, Brazil (Amphibia, Anura).

    PubMed

    Dias, Iuri Ribeiro; de Mira-Mendes, Caio Vinicius; Souza-Costa, Carlos Augusto; Juncá, Flora Acuña; Solé, Mirco

    2017-01-01

    Advertisement calls can be used to aid solving taxonomic problems and understanding the evolution of certain groups. In this study, the advertisement call of Eleutherodactylus bilineatus is described. It is composed by two different notes with a total duration of 0.529-4.241 seconds and dominant frequency of 1.72-3.45 kHz. Additionally, new data is provided on the geographical distribution of Eleutherodactylus bilineatus and the most inland record for this species.

  8. Spermiogenesis and spermatozoon ultrastructure of Diplodiscus subclavatus (Pallas, 1760) (Paramphistomoidea, Diplodiscidae), an intestinal fluke of the pool frog Rana lessonae (Amphibia, Anura).

    PubMed

    Bakhoum, A J S; Torres, J; Shimalov, V V; Bâ, C T; Miquel, J

    2011-01-01

    Spermiogenesis in Diplodiscus subclavatus begins with the formation of the zone of differentiation presenting two centrioles associated with striated roots and an intercentriolar body. The latter presents seven electron-dense layers with a fine central plate and three plates on both sides. The external pair of these electron-dense layers is formed by a granular row. Each centriole develops into a free flagellum, both of them growing orthogonally in relation to the median cytoplasmic process. After the flagellar rotation and before the proximodistal fusion of both flagella with the median cytoplasmic process four attachment zones were already observed in several cross-sections indicating the area of fusion. Spinelike bodies are also observed in the differentiation zone before the fusion of flagella. Finally, the constriction of the ring of arched membranes gives rise to the young spermatozoon that detaches from the residual cytoplasm. The mature spermatozoon of D. subclavatus shows all the classical characters observed in Digenea spermatozoa such as two axonemes of different length of the 9+"1" trepaxonematan pattern, nucleus, mitochondrion, two bundles of parallel cortical microtubules and granules of glycogen. However, some peculiarities such as a well-developed lateral expansion associated with external ornamentation of the plasma membrane and spinelike bodies combined with their area of appearance distinguish the ultrastructural organization of the sperm cells of D. subclavatus from those of other digeneans.

  9. A new species of terrestrial-breeding frog (Amphibia, Craugastoridae, Pristimantis) from high elevations of the Pui Pui Protected Forest in central Peru.

    PubMed

    Lehr, Edgar; von May, Rudolf

    2017-01-01

    We describe a new species of Pristimantis from upper montane forests and high Andean grasslands of the Pui Pui Protected Forest and its close surroundings, Región Junín, central Peru. The description of the new species is based on 34 specimens found at elevations between 3400 and 3936 m a.s.l. Pristimantis attenboroughisp. n. is characterized by a snout-vent length of 14.6-19.2 mm in adult males (n = 21), 19.2-23.0 mm in adult females (n = 10), and is compared morphologically and genetically with other taxonomically and biogeographically relevant species of Pristimantis. The new species is characterized by having narrow digits that lack circumferential grooves, irregularly shaped, discontinuous dorsolateral folds, and absence of both tympanic membrane and tympanic annulus. The high similarity in morphology between P. attenboroughisp. n. and members of the Andean genera Phrynopus and Bryophryne provides an example for convergent evolution, and highlights the importance of using molecular data to justify generic assignment. Pristimantis attenboroughisp. n. is most similar to Phrynopus chaparroi from the Región Junín, suggesting that the generic placement of this species needs to be revised. Phylogenetically the new species belongs to the Pristimantis danae species Group, a clade that includes several Pristimantis species distributed in the montane forests of central Peru, including P. albertus, P. aniptopalmatus, P. ornatus, and P. stictogaster.

  10. Temporal dynamics of biotic and abiotic drivers of litter decomposition.

    PubMed

    García-Palacios, Pablo; Shaw, E Ashley; Wall, Diana H; Hättenschwiler, Stephan

    2016-05-01

    Climate, litter quality and decomposers drive litter decomposition. However, little is known about whether their relative contribution changes at different decomposition stages. To fill this gap, we evaluated the relative importance of leaf litter polyphenols, decomposer communities and soil moisture for litter C and N loss at different stages throughout the decomposition process. Although both microbial and nematode communities regulated litter C and N loss in the early decomposition stages, soil moisture and legacy effects of initial differences in litter quality played a major role in the late stages of the process. Our results provide strong evidence for substantial shifts in how biotic and abiotic factors control litter C and N dynamics during decomposition. Taking into account such temporal dynamics will increase the predictive power of decomposition models that are currently limited by a single-pool approach applying control variables uniformly to the entire decay process.

  11. The role of extensional viscosity in frog tongue projection

    NASA Astrophysics Data System (ADS)

    Noel, Alexis; Wagner, Caroline; McKinley, Gareth; Mendelson, Joe; Hu, David

    2014-11-01

    Frogs and other amphibians capture insects through high-speed tongue projection, some achieving tongue accelerations of over fifty times gravity. In this experimental study, we investigate how a frog's sticky saliva enables high-speed prey capture. At the Atlanta zoo, we used high-speed video to film the trajectory of frog tongues during prey capture. We have also designed and built a portable extensional rheometer; by following the capillary-driven thinning in the diameter of a thread of saliva we characterize the relaxation time and extensional viscosity and so infer the adhesive force between the frog tongue and prey.

  12. The effect of saprophagous macrofauna on litter decomposition

    NASA Astrophysics Data System (ADS)

    Frouz, Jan

    2016-04-01

    Previous experiments show that feeding of the larvae of Bibionidae on lef litter cause short term increase of respiration but in long term the decomposition of bibio feces is slower than decomposition of litter from which feces were produced. To understand why excrements of decompose more slowly than leaf litter, we fed Bibio marci larvae the litter of tree species differing in litter quality (Alnus glutinosa, Salix caprea, and Quercus robur) and then measured respiration induced by litter and excrements. We also measured respiration induced by the same litter artificially modified to mimic faunal effects; the litter was modified by grinding, grinding with alkalinization to pH 11, grinding with coating by kaolinite, and grinding with both alkalinization and coating. Decomposition of excrements tended to be slower for willow and was significantly slower for oak and alder than for the corresponding litter. With oak, decomposition was slower for all artificially modified litter than for non-modified litter. The reduction in the decomposition was similar for excrements and for alder and willow litter that was ground, coated, and alkalinized. In alder, a similar reduction was found in ground and alkalinized litter. 13C NMR indicated that gut passage increases aliphatic components and decreases polysaccharides. Pyrolysis indicated that gut passage increases the ratio of guaiacyl to hydroxymethyl derivatives in lignin. Our findings indicate that the decreased decomposition rate of excrements might result from the removal of easily available polysaccharides, the increase in aliphatic components, an increase in the resistant components of lignin, the accumulation of microbial cell walls, and the binding of nitrogen into complexes with aromatic components. Several of these mechanisms are supported or determined by litter alkalinization during gut passage.

  13. Faint Infrared-Excess Field Galaxies: FROGs

    NASA Astrophysics Data System (ADS)

    Moustakas, L. A.; Davis, M.; Zepf, S. E.; Bunker, A. J.

    Deep near-infrared and optical imaging surveys in the field reveal a curious population of galaxies that are infrared-bright (I-K>4), yet with relatively blue optical colors (V-I<2). Their surface density, several per square arcminute at K>20, is high enough that if placed at z>1 as our models suggest, their space densities are about one-tenth of phi-*. The colors of these ``faint red outlier galaxies'' (fROGs) may derive from exceedingly old underlying stellar populations, a dust-embedded starburst or AGN, or a combination thereof. Determining the nature of these fROGs, and their relation with the I-K>6 ``extremely red objects,'' has implications for our understanding of the processes that give rise to infrared-excess galaxies in general. We report on an ongoing study of several targets with HST & Keck imaging and Keck/LRIS multislit spectroscopy.

  14. A new species of glossiphoniid leech from Rana pretiosa (Amphibia: Ranidae) in Oregon.

    PubMed

    Siddall, Mark E; Bowerman, Jay

    2006-08-01

    A new species of ectoparasitic glossiphoniid leech was found feeding on frogs in the Nature Center Pond and elsewhere in Deschutes County, Oregon. The new species of Placobdella resembles the southern alligator leech, Placobdella multilineata Moore, 1953, notwithstanding their vast geographic separation in North America. The new species is readily distinguished by possessing subdivided annuli, by its papillation and pigmentation patterns as well as by the arrangement of ovarian tissues. There is strong evidence of nocturnality and of the potential for parasitizing humans.

  15. Environmental fate of roxarsone in poultry litter. Part II. Mobility of arsenic in soils amended with poultry litter

    USGS Publications Warehouse

    Rutherford, D.W.; Bednar, A.J.; Garbarino, J.R.; Needham, R.; Staver, K.W.; Wershaw, R. L.

    2003-01-01

    Poultry litter often contains arsenic as a result of organo-arsenical feed additives. When the poultry litter is applied to agricultural fields, the arsenic is released to the environment and may result in increased arsenic in surface and groundwater and increased uptake by plants. The release of arsenic from poultry litter, litter-amended soils, and soils without litter amendment was examined by extraction with water and strong acids (HCI and HN03). The extracts were analyzed for As, C, P, Cu, Zn, and Fe. Copper, zinc, and iron are also poultry feed additives. Soils with a known history of litter application and controlled application rate of arsenic-containing poultry litter were obtained from the University of Maryland Agricultural Experiment Station. Soils from fields with long-term application of poultry litter were obtained from a tilled field on the Delmarva Peninsula (MD) and an untilled Oklahoma pasture. Samples from an adjacent forest or nearby pasture that had no history of litter application were used as controls. Depth profiles were sampled for the Oklahoma pasture soils. Analysis of the poultry litter showed that 75% of the arsenic was readily soluble in water. Extraction of soils shows that weakly bound arsenic mobilized by water correlates positively with C, P, Cu, and Zn in amended fields and appears to come primarily from the litter. Strongly bound arsenic correlates positively with Fe in amended fields and suggests sorption or coprecipitation of As and Fe in the soil column.

  16. Neuromuscular control of prey capture in frogs.

    PubMed Central

    Nishikawa, K C

    1999-01-01

    While retaining a feeding apparatus that is surprisingly conservative morphologically, frogs as a group exhibit great variability in the biomechanics of tongue protraction during prey capture, which in turn is related to differences in neuromuscular control. In this paper, I address the following three questions. (1) How do frog tongues differ biomechanically? (2) What anatomical and physiological differences are responsible? (3) How is biomechanics related to mechanisms of neuromuscular control? Frog species use three non-exclusive mechanisms to protract their tongues during feeding: (i) mechanical pulling, in which the tongue shortens as its muscles contract during protraction; (ii) inertial elongation, in which the tongue lengthens under inertial and muscular loading; and (iii) hydrostatic elongation, in which the tongue lengthens under constraints imposed by the constant volume of a muscular hydrostat. Major differences among these functional types include (i) the amount and orientation of collagen fibres associated with the tongue muscles and the mechanical properties that this connective tissue confers to the tongue as a whole; and (ii) the transfer of intertia from the opening jaws to the tongue, which probably involves a catch mechanism that increases the acceleration achieved during mouth opening. The mechanisms of tongue protraction differ in the types of neural mechanisms that are used to control tongue movements, particularly in the relative importance of feed-forward versus feedback control, in requirements for precise interjoint coordination, in the size and number of motor units, and in the afferent pathways that are involved in coordinating tongue and jaw movements. Evolution of biomechanics and neuromuscular control of frog tongues provides an example in which neuromuscular control is finely tuned to the biomechanical constraints and opportunities provided by differences in morphological design among species. PMID:10382226

  17. CHARACTERISTICS OF FROG CARCINOMA IN TISSUE CULTURE.

    PubMed

    Lucké, B

    1939-08-31

    The adenocarcinoma of leopard frogs may be cultivated with ease in plasma media. In such cultures two types of growth occur with regularity. The first is in the form of tubules which promptly grow out in the solid medium and retain their tubular form as long as they remain completely enveloped by plasma. When, however, they make contact with the surface of the glass, they adhere to it, the part in contact becomes flat, and its cells now grow no longer as tubules but as membranes. The manner of growth in vitro resembles the growth of transplants of the same tumor in the anterior chamber of the living eye, thus suggesting that in each case the habit of growth is determined by the same morphogenetic factors, i.e. those inherent in the cells themselves, and those depending on interfacial forces. The malignant cells of the frog carcinoma have the attributes which in general distinguish malignant cells from normal cells of corresponding type. In comparison with adult kidney cells, their normal homologues, the conspicuous properties of frog carcinoma cells are: larger and more variable size and shape of cell body, of nucleus, and nucleolus; coarser and denser structure of cytoplasm, of nucleoplasm, and of nuclear membrane; increase in number of mitochondria, and more frequent occurrence of mitosis. These cytological characteristics remain unaltered in cultures maintained for as long as six months. Frog carcinoma is a transmissible disease due to an agent which induces inclusion bodies, and which has other attributes indicating that it is a virus. The general correspondence in character between its cells and the malignant cells of mammalian tumors of diverse origin suggests that neoplastic phenomena are essentially alike, no matter in what group of animals they occur or what their causal factors may be.

  18. Yolk pigments of the Mexican leaf frog.

    PubMed

    Marinetti, G V; Bagnara, J T

    1983-02-25

    Eggs of the Mexican leaf frog contain blue and yellow pigments identified as biliverdin and lutein, respectively. Both pigments are bound to proteins that occur in crystalline form in the yolk platelet. The major blue pigment is biliverdin IX alpha. The eggs vary in color from brilliant blue to pale yellow-green depending on the amount of each pigment. These pigments may provide protective coloration to the eggs.

  19. Trombiculid mites (Hannemania sp.) in Leptodactylus chaquensis (Amphibia: Anura) inhabiting selected soybean and rice agroecosystems of Argentina.

    PubMed

    Attademo, Andrés M; Peltzer, Paola M; Lajmanovich, Rafael C; Junges, Celina; Bassó, Agustín; Cabagna-Zenklusen, Mariana

    2012-09-01

    Trombiculid mites are known to parasitize a variety of amphibian species; however, few comparisons of mite parasitism among sites have been made. Here, Hannemania sp. parasitism in frogs (Leptodactylus chaquensis) inhabiting agroecosystems from mideastern Argentina was described. A total of 40 adult frogs (22 females and 18 males) were analyzed to detect ectoparasite Hannemania spp. larvae. Prevalence and mean abundance of Hannemania sp. were consistently higher in frogs from the agroecosystems (rice and soybean fields) than from two reference sites. Leptodactylus chaquensis might be considered an important host species of Hannemania sp., particularly in agricultural areas.

  20. How does litter cover, litter diversity and fauna affect sediment discharge and runoff?

    NASA Astrophysics Data System (ADS)

    Goebes, Philipp; Seitz, Steffen; Kühn, Peter; Scholten, Thomas

    2013-04-01

    Litter cover plays a major role in soil erosion processes. It is known that litter cover reduces erosivity of raindrops, decreases sediment discharge and lowers runoff volume compared to bare ground. However, in the context of biodiversity, the composition of litter cover, its effect on sediment discharge and runoff volume and their influence on soil erosion have not yet been analyzed in detail. Focusing on initial soil erosion (splash), our experimental design is designated to get a better understanding of these mechanisms. The experiments were carried out within the DFG research unit "Biodiversity and Ecosystem Functioning (BEF)-China" in subtropical China. The "New Integrated Litter Experiment (NILEx)" used as platform combining different subprojects of BEF-China dealing with "decomposition and nutrient cycling", "mechanisms of soil erosion" and "functional effects of herbivores, predators and saproxylics" in one experiment. In NILEx, 96 40cm x 40cm runoff plots on two hill slopes inside a castanea molissima forest plantation have been installed and filled with seven different types of litter cover. 16 one-species plots, 24 two-species plots, 4 four-species plots and 4 bare ground plots have been set up, each replicated once. We prepared 48 Plots with traps (Renner solution) for soil macrofauna (diplopods and collembola), so half of the plots were kept free from fauna while the other half was accessible for fauna. Rainfall was generated artificially by using a rainfall simulator with a continuous and stable intensity of 60 mm/h. Our experiments included two runs of 20 minutes duration each, both conducted at two different time steps (summer 2012 and autumn 2012). Runoff volume and sediment discharge were measured every 5 minutes during one rainfall run. Litter coverage and litter mass were recorded at the beginning (summer 2012) and at the end of the experiment (autumn 2012). Our results show that sediment discharge as well as runoff volume decreases

  1. Quantifying litter decomposition losses to dissolved organic carbon and respiration

    NASA Astrophysics Data System (ADS)

    Soong, J.; Parton, W. J.; Calderon, F. J.; Guilbert, K.; Cotrufo, M.

    2013-12-01

    As litter decomposes its carbon is lost from the litter layer, largely through microbial processing. However, much of the carbon lost from the surface litter layer during decomposition is not truly lost from the ecosystem but gets transferred to the soil through fragmentation and leaching of dissolved organic carbon (DOC). This DOC in the soil acts as a stock of soil organic matter (SOM) to be utilized by soil microbes, stabilized in the soil, or leached further through the soil profile. The total amount of C that ends up leaching from litter to the soil, as well as its chemical composition, has important implications on the residence time of decomposing litter C in the soil and is not currently well parameterized in models. In this study we aim to quantify the proportional relationship between CO2 efflux and DOC partitioning during decomposition of fresh leaf litter with distinct structural and chemical composition. The results from this one-year laboratory incubation show a clear relationship between the lignin to cellulose ratios of litter and DOC to CO2 partitioning during four distinct phases of litter decomposition. For example, bluestem grass litter with a low lignin to cellulose ratio loses almost 50% of its C as DOC whereas pine needles with a high lignin to cellulose ratio loses only 10% of its C as DOC, indicating a potential ligno-cellulose complexation effect on carbon use efficiency during litter decomposition. DOC production also decreases with time during decomposition, correlating with increasing lignin to cellulose ratios as decomposition progresses. Initial DOC leaching can be predicted based on the amount of labile fraction in each litter type. Field data using stable isotope labeled bluestem grass show that about 18% of the surface litter C lost in 18 months of decomposition is stored in the soil, and that over 50% of this is recovered in mineral-associated heavy SOM fractions, not as litter fragments, confirming the relative importance of the

  2. Arsenic speciation and reactivity in poultry litter

    USGS Publications Warehouse

    Arai, Y.; Lanzirotti, A.; Sutton, S.; Davis, J.A.; Sparks, D.L.

    2003-01-01

    Recent U.S. government action to lower the maximum concentration levels (MCL) of total arsenic (As) (10 ppb) in drinking water has raised serious concerns about the agricultural use of As-containing biosolids such as poultry litter (PL). In this study, solid-state chemical speciation, desorbability, and total levels of As in PL and long-term amended soils were investigated using novel synchrotronbased probing techniques (microfocused (??) synchrotron X-ray fluorescence (SXRF) and ??-X-ray absorption near-edge structure (XANES) spectroscopies) coupled with chemical digestion and batch experiments. The total As levels in the PL were as high as ???50 mg kg-1, and As(II/III and V) was always concentrated in abundant needle-shaped microscopic particles (???20/ ??m x 850 ??m) associated with Ca, Cu, and Fe and to a lesser extent with S, CI, and Zn. Postedge XANES features of litter particles are dissimilar to those of the organo-As(V) compound in poultry feed (i.e., roxarsone), suggesting possible degradation/transformation of roxarsone in the litter and/or in poultry digestive tracts. The extent of As desorption from the litter increased with increasing time and pH from 4.5 to 7, but at most 15% of the total As was released after 5 d at pH 7, indicating the presence of insoluble phases and/or strongly retained soluble compounds. No significant As accumulation (< 15 mg kg-1) was found in long-term PL-a mended agricultural surface soils. This suggests that As in the PL may have undergone surface and subsurface transport processes. Our research results raise concerns about long-term PL amendment effects on As contamination in surrounding soilwater environments.

  3. Do leaf-litter attributes affect the richness of leaf-litter ants?

    PubMed

    Silva, Paulo S D; Bieber, A G D; Corrêa, M M; Leal, I R

    2011-10-01

    The search for factors shaping leaf-litter ant communities has received particular attention due to the essential role of these insects in many ecological processes. Here, we aimed to investigate how the number of leaves and leaf morphotypes affect the litter-ant species density at forest edge and interior in an Atlantic Forest remnant in the state of Alagoas, Brazil. This study was developed based on 28 litter plots (1m² each), 14 in the forest interior and 14 in the forest edge. As we early expected, ant species density increased with increasing both the number of leaves and the number of leaf morphotypes, but this result was clearly influenced by plot location. Contrasting with the forest interior, ant species density did not increase as the number of leaves increased in the forest edge. Possibly, factors such as plant species richness, vegetation structure and environmental conditions affect ant species density as well as promote a patchy distribution of species in ant communities along the edge-to-interior gradient. Our findings suggest that edge-affected forests present more simplified ant communities, with different factors shaping its structure. We encourage future studies to include leaf litter heterogeneity as one of the explanatory variables investigated.

  4. [Forest litter decomposition and its responses to global climate change].

    PubMed

    Yang, Wan-Qin; Deng, Ren-Ju; Zhang, Jian

    2007-12-01

    Litter decomposition is one of the important processes in forest ecosystem, which is controlled by both biotic and abiotic factors such as climate, litter quality, and soil organisms. Up to now, numerous studies have been made on the dynamics of aboveground litter in different forest ecosystems, nutrient release during its decomposition, and effects of biotic and abiotic factors on the decomposition, but less information has been reported on the decomposition of belowground forest litter. Recently, the responses of forest litter decomposition to global climate change characterized by elevated atmospheric CO2 concentration and temperature have got worldwide concern, but there remains uncertainty in research results. In the further study, more attention should be paid on the contribution of forest litter decomposition to soil organic carbon sequestration, the physical, chemical and biological processes of below- and above-ground litter decomposition, the responses of forest litter decomposition to the ecological factors (e.g. seasonal freeze-thaw cycle and drying-rewetting cycle) and their interactions, and the mechanisms of litter (especially belowground litter) decomposition responses to global climate change.

  5. Trees as templates for tropical litter arthropod diversity.

    PubMed

    Donoso, David A; Johnston, Mary K; Kaspari, Michael

    2010-09-01

    Increased tree species diversity in the tropics is associated with even greater herbivore diversity, but few tests of tree effects on litter arthropod diversity exist. We studied whether tree species influence patchiness in diversity and abundance of three common soil arthropod taxa (ants, gamasid mites, and oribatid mites) in a Panama forest. The tree specialization hypothesis proposes that tree-driven habitat heterogeneity maintains litter arthropod diversity. We tested whether tree species differed in resource quality and quantity of their leaf litter and whether more heterogeneous litter supports more arthropod species. Alternatively, the abundance-extinction hypothesis states that arthropod diversity increases with arthropod abundance, which in turn tracks resource quantity (e.g., litter depth). We found little support for the hypothesis that tropical trees are templates for litter arthropod diversity. Ten tree species differed in litter depth, chemistry, and structural variability. However, the extent of specialization of invertebrates on particular tree taxa was low and the more heterogeneous litter between trees failed to support higher arthropod diversity. Furthermore, arthropod diversity did not track abundance or litter depth. The lack of association between tree species and litter arthropods suggests that factors other than tree species diversity may better explain the high arthropod diversity in tropical forests.

  6. Abundance of litter on Condor seamount (Azores, Portugal, Northeast Atlantic)

    NASA Astrophysics Data System (ADS)

    Pham, C. K.; Gomes-Pereira, J. N.; Isidro, E. J.; Santos, R. S.; Morato, T.

    2013-12-01

    Marine litter is an emerging problem for the world's ocean health but little is known on its distribution and abundance on seamounts and how it affects deep-sea ecosystems. The scientific underwater laboratory set up on Condor seamount offered an ideal case study for the first documentation of litter distribution on a shallow seamount with historical fishing. A total of 48 video transects deployed on the summit (n=45) and the northern flank (n=3) covered an area of 0.031 and 0.025km2, respectively, revealing 55 litter items. Litter density on the summit was 1439 litter items km-2, whilst on the deeper northern flank, estimates indicate densities of 397 litter items km-2. Lost fishing line was the dominant litter item encountered on both areas (73% of total litter on the summit and 50% on northern flank), all being entirely or partly entangled in the locally abundant gorgonians Dentomuricea cf. meteor and Viminella flagellum. Other items included lost weights, anchors and glass bottles. The predominance of lost fishing gear identifies the source of litter on Condor seamount as exclusively ocean-based and related to fishing activities. Abundance of litter on the Condor seamount was much lower than that reported from other locations closer to populated areas.

  7. Statistical analysis of litter experiments in teratology

    SciTech Connect

    Williams, R.; Buschbom, R.L.

    1982-11-01

    Teratological data is binary response data (each fetus is either affected or not) in which the responses within a litter are usually not independent. As a result, the litter should be taken as the experimental unit. For each litter, its size, n, and the number of fetuses, x, possessing the effect of interest are recorded. The ratio p = x/n is then the basic data generated by the experiment. There are currently three general approaches to the analysis of teratological data: nonparametric, transformation followed by t-test or ANOVA, and parametric. The first two are currently in wide use by practitioners while the third is relatively new to the field. These first two also appear to possess comparable power levels while maintaining the nominal level of significance. When transformations are employed, care must be exercised to check that the transformed data has the required properties. Since the data is often highly asymmetric, there may be no transformation which renders the data nearly normal. The parametric procedures, including the beta-binomial model, offer the possibility of increased power.

  8. Quality of soluble organic C, N, and P produced by different types and species of litter: root litter versus leaf litter

    USDA-ARS?s Scientific Manuscript database

    In forested ecosystems, the quality of dissolved organic matter (DOM) produced by freshly senesced litter may differ by litter type and species, and these differences may influence the amount of DOM that is respired versus that which may either contribute to soil organic matter accumulation or be le...

  9. Using a Phototransduction System to Monitor the Isolated Frog Heart

    ERIC Educational Resources Information Center

    Stephens, Philip J.

    2015-01-01

    A simple and inexpensive method of monitoring the movement of an isolated frog heart provides comparable results to those obtained with a force transducer. A commercially available photoresistor is integrated into a Wheatstone bridge circuit, and the output signal is interfaced directly with a recording device. An excised, beating frog heart is…

  10. Coleman Revisited: School Segregation, Peers, and Frog Ponds

    ERIC Educational Resources Information Center

    Goldsmith, Pat Rubio

    2011-01-01

    Students from minority segregated schools tend to achieve and attain less than similar students from White segregated schools. This study examines whether peer effects can explain this relationship using normative models and frog-pond models. Normative models (where peers become alike) suggest that minority schoolmates are a liability. Frog-pond…

  11. Using a Phototransduction System to Monitor the Isolated Frog Heart

    ERIC Educational Resources Information Center

    Stephens, Philip J.

    2015-01-01

    A simple and inexpensive method of monitoring the movement of an isolated frog heart provides comparable results to those obtained with a force transducer. A commercially available photoresistor is integrated into a Wheatstone bridge circuit, and the output signal is interfaced directly with a recording device. An excised, beating frog heart is…

  12. Coleman Revisited: School Segregation, Peers, and Frog Ponds

    ERIC Educational Resources Information Center

    Goldsmith, Pat Rubio

    2011-01-01

    Students from minority segregated schools tend to achieve and attain less than similar students from White segregated schools. This study examines whether peer effects can explain this relationship using normative models and frog-pond models. Normative models (where peers become alike) suggest that minority schoolmates are a liability. Frog-pond…

  13. Foothill yellow-legged frog conservation assessment in California

    Treesearch

    Marc P. Hayes; Clara A. Wheeler; Amy J. Lind; Gregory A. Green; Diane C. Macfarlane

    2016-01-01

    The foothill yellow-legged frog (Rana boylii) is a stream-breeding amphibian that has experienced significant population declines over a large portion of its historical range. This frog is nearing extirpation in much of the Sierra Nevada region where existing populations are sparse. Water development and diversions are likely to be the primary...

  14. Infrared reflectance in leaf-sitting neotropical frogs.

    PubMed

    Schwalm, P A; Starrett, P H; McDiarmid, R W

    1977-06-10

    Two members of the glass-frog family Centrolenidae (Centrolenella fleischmanni, C. prosoblepon) and the hylid subfamily Phyllomedusinae (Agalychnis moreletii, Pachymedusa dacnicolor) reflect near-infrared light (700 to 900 nanometers) when examined by infrared color photography. Infrared reflectance may confer adaptive advantage to these arboreal frogs both in thermoregulation and infrared cryptic coloration.

  15. Modeling potential river management conflicts between frogs and salmonids

    Treesearch

    Steven F. Railsback; Bret C. Harvey; Sarah J. Kupferberg; Margaret M. Lang; Scott McBain; Hart H. Welsh

    2016-01-01

    Management of regulated rivers for yellow-legged frogs (Rana boylii) and salmonids exemplifies potential conflicts among species adapted to different parts of the natural flow and temperature regimes. Yellow-legged frogs oviposit in rivers in spring and depend on declining flows and warming temperatures for egg and tadpole survival and growth,...

  16. The effects of UV radiation, litter chemistry, and drought on desert litter decomposition

    NASA Astrophysics Data System (ADS)

    Lee, H.; Nieto, B.; Hewins, D. B.; Barnes, P. W.; McDowell, N. G.; Pockman, W.; Rahn, T.; Throop, H. L.

    2011-12-01

    Recent studies suggest that photodegradation by solar UV radiation can be a major driver of litter decomposition in dryland ecosystems. The importance of photodegradation in litter decomposition appears to decline with precipitation, suggesting that the relative importance of photodegradation may increase given current projections of future increases in drought severity in the southwestern USA. Several previous studies indicate that UV-B radiation (280-320 nm) is the most effective waveband in breaking chemical bonds forming organic material, but whether UV-B exposure may facilitate subsequent decomposition by microbes (i.e., photo-priming) has received little attention. In this study, we tested the effects of pre-exposure UV radiation (photo-priming), litter chemistry (lignin and cellulose content and nitrogen content), and drought on the rate of litter decomposition in a semi-arid ecosystem. To understand the effects of UV radiation on litter decomposition, we pre-exposed litter to three radiation treatments: control (no radiation), UV-A+visible, UV-A+UV-B+visible. Litter was exposed to the equivalent of three months' solar radiation of southern New Mexico prior to microbial decomposition. There were three litter types: basswood sheets (high lignin content), pure cellulose filter paper, and mesquite (Prosopis glandulosa) leaflets. Following radiation treatment, litter was placed in mesh litterbags that were buried within a large-scale precipitation manipulation experiment at the Sevilleta Long-Term Ecological Research site: control (ambient precipitation), elevated precipitation (x2 ambient precipitation), and drought (x0.5 ambient precipitation). We collected a subset of bags at 0, 1, 3, and 6 months and measured mass remaining and carbon (C) and nitrogen (N) content. After 6 months, mass remaining of filter paper and basswood sheets did not differ from the initial mass, but mesquite mass remaining declined over 30%. The pre-exposure UV effects had minimal

  17. Odour emissions from poultry litter - A review litter properties, odour formation and odorant emissions from porous materials.

    PubMed

    Dunlop, Mark W; Blackall, Patrick J; Stuetz, Richard M

    2016-07-15

    Odour emissions from meat chicken sheds can at times cause odour impacts on surrounding communities. Litter is seen as the primary source of this odour. Formation and emission of odour from meat chicken litter during the grow-out period are influenced by various factors such as litter conditions, the environment, microbial activity, properties of the odorous gases and management practices. Odour emissions vary spatially and temporally. This variability has made it challenging to understand how specific litter conditions contribute to odour emissions from the litter and production sheds. Existing knowledge on odorants, odour formation mechanisms and emission processes that contribute to odour emissions from litter are reviewed. Litter moisture content and water thermodynamics (i.e. water activity, Aw) are also examined as factors that contribute to microbial odour formation, physical litter conditions and the exchange of individual odorant gases at the air-water interface. Substantial opportunities exist for future research on litter conditions and litter formation mechanisms and how these contribute to odour emissions. Closing this knowledge gap will improve management strategies that intercept and interfere with odour formation and emission processes leading to an overall reduction in the potential to cause community impacts.

  18. Montagnuphilones A-G, Azaphilones from Montagnulaceae sp. DM0194, a Fungal Endophyte of Submerged Roots of Persicaria amphibia.

    PubMed

    Luo, Jian-Guang; Xu, Ya-Ming; Sandberg, Dustin C; Arnold, A Elizabeth; Gunatilaka, A A Leslie

    2017-01-27

    Seven azaphilones, montagnuphilones A-G (1-7), together with previously known azaphilones 8-11, were encountered in Montagnulaceae sp. DM0194, an endophytic fungus isolated from submerged roots of Persicaria amphibia. The structures of 1-7 were elucidated on the basis of their MS and NMR spectroscopic analysis. Compounds 1-8 were evaluated for their cytotoxicity and ability to inhibit nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophage cells. Among these, none were found to be cytotoxic to RAW264.7 cells up to 100.0 μM, but 8, 5, and 2 showed NO inhibitory activity with IC50 values of 9.2 ± 0.9, 25.5 ± 1.1, and 39.6 ± 1.8 μM, respectively.

  19. Carnosine in the brain and olfactory system of amphibia and reptilia: a comparative study using immunocytochemical and biochemical methods.

    PubMed

    Artero, C; Martì, E; Biffo, S; Mulatero, B; Andreone, C; Margolis, F L; Fasolo, A

    1991-09-16

    The pattern of distribution of carnosine-like immunoreactivity and its relation to glial fibrillary acidic protein immunoreactivity have been studied in two lizards (Gallotia galloti and Tarentola delalandii) and in two anuran amphibians (Rana esculenta and Xenopus laevis) using immunocytochemical techniques. Biochemical data obtained by paper electrophoresis show that the dipeptides carnosine and homocarnosine are both present in the brain of all the species examined. In the central nervous system of both anurans and reptilians, carnosine immunoreactivity is localized in glial cells. An important species difference is, however, seen in the olfactory system since primary olfactory neurons and their processes extending to the olfactory bulb are carnosine positive in reptiles, whereas they are not immunostained in anurans. Thus, the cellular distribution of carnosine immunoreactivity in reptilians is very similar to that observed in birds and mammals and is distinct from that seen in amphibia.

  20. Mixing effects of understory plant litter on decomposition and nutrient release of tree litter in two plantations in Northeast China.

    PubMed

    Zhao, Lei; Hu, Ya-Lin; Lin, Gui-Gang; Gao, Yong-chao; Fang, Yun-Ting; Zeng, De-Hui

    2013-01-01

    Understory vegetation plays a crucial role in carbon and nutrient cycling in forest ecosystems; however, it is not clear how understory species affect tree litter decomposition and nutrient dynamics. In this study, we examined the impacts of understory litter on the decomposition and nutrient release of tree litter both in a pine (Pinus sylvestris var. mongolica) and a poplar (Populus × xiaozhuanica) plantation in Northeast China. Leaf litter of tree species, and senesced aboveground materials from two dominant understory species, Artemisia scoparia and Setaria viridis in the pine stand and Elymus villifer and A. sieversiana in the poplar stand, were collected. Mass loss and N and P fluxes of single-species litter and three-species mixtures in each of the two forests were quantified. Data from single-species litterbags were used to generate predicted mass loss and N and P fluxes for the mixed-species litterbags. In the mixture from the pine stand, the observed mass loss and N release did not differ from the predicted value, whereas the observed P release was greater than the predicted value. However, the presence of understory litter decelerated the mass loss and did not affect N and P releases from the pine litter. In the poplar stand, litter mixture presented a positive non-additive effect on litter mass loss and P release, but an addition effect on N release. The presence of understory species accelerated only N release of poplar litter. Moreover, the responses of mass loss and N and P releases of understory litter in the mixtures varied with species in both pine and poplar plantations. Our results suggest that the effects of understory species on tree litter decomposition vary with tree species, and also highlight the importance of understory species in litter decomposition and nutrient cycles in forest ecosystems.

  1. Climatic controls on leaf litter decomposition across European forests and grasslands revealed by reciprocal litter transplantation experiments

    NASA Astrophysics Data System (ADS)

    Portillo-Estrada, Miguel; Pihlatie, Mari; Korhonen, Janne F. J.; Levula, Janne; Frumau, Arnoud K. F.; Ibrom, Andreas; Lembrechts, Jonas J.; Morillas, Lourdes; Horváth, László; Jones, Stephanie K.; Niinemets, Ülo

    2016-03-01

    Carbon (C) and nitrogen (N) cycling under future climate change is associated with large uncertainties in litter decomposition and the turnover of soil C and N. In addition, future conditions (especially altered precipitation regimes and warming) are expected to result in changes in vegetation composition, and accordingly in litter species and chemical composition, but it is unclear how such changes could potentially alter litter decomposition. Litter transplantation experiments were carried out across six European sites (four forests and two grasslands) spanning a large geographical and climatic gradient (5.6-11.4 °C in annual temperature 511-878 mm in precipitation) to gain insight into the climatic controls on litter decomposition as well as the effect of litter origin and species. The decomposition k rates were overall higher in warmer and wetter sites than in colder and drier sites, and positively correlated with the litter total specific leaf area. Also, litter N content increased as less litter mass remained and decay went further. Surprisingly, this study demonstrates that climatic controls on litter decomposition are quantitatively more important than species or site of origin. Cumulative climatic variables, precipitation, soil water content and air temperature (ignoring days with air temperatures below zero degrees Celsius), were appropriate to predict the litter remaining mass during decomposition (Mr). Mr and cumulative air temperature were found to be the best predictors for litter carbon and nitrogen remaining during the decomposition. Using mean annual air temperature, precipitation, soil water content and litter total specific leaf area as parameters we were able to predict the annual decomposition rate (k) accurately.

  2. 49 CFR 213.355 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Frog guard rails and guard faces; gage. 213.355... Higher § 213.355 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs... distance between the gage line of a frog to the guard line 1 of its guard rail or guarding face, measured...

  3. 49 CFR 213.355 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Frog guard rails and guard faces; gage. 213.355... Higher § 213.355 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs... distance between the gage line of a frog to the guard line 1 of its guard rail or guarding face, measured...

  4. 49 CFR 213.355 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Frog guard rails and guard faces; gage. 213.355... Higher § 213.355 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs... distance between the gage line of a frog to the guard line 1 of its guard rail or guarding face, measured...

  5. 49 CFR 213.355 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Frog guard rails and guard faces; gage. 213.355... Higher § 213.355 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs... distance between the gage line of a frog to the guard line 1 of its guard rail or guarding face, measured...

  6. 49 CFR 213.355 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Frog guard rails and guard faces; gage. 213.355... Higher § 213.355 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs... distance between the gage line of a frog to the guard line 1 of its guard rail or guarding face, measured...

  7. Tongue adhesion in the horned frog Ceratophrys sp.

    NASA Astrophysics Data System (ADS)

    Kleinteich, Thomas; Gorb, Stanislav N.

    2014-06-01

    Frogs are well-known to capture elusive prey with their protrusible and adhesive tongues. However, the adhesive performance of frog tongues and the mechanism of the contact formation with the prey item remain unknown. Here we measured for the first time adhesive forces and tongue contact areas in living individuals of a horned frog (Ceratophrys sp.) against glass. We found that Ceratophrys sp. generates adhesive forces well beyond its own body weight. Surprisingly, we found that the tongues adhered stronger in feeding trials in which the coverage of the tongue contact area with mucus was relatively low. Thus, besides the presence of mucus, other features of the frog tongue (surface profile, material properties) are important to generate sufficient adhesive forces. Overall, the experimental data shows that frog tongues can be best compared to pressure sensitive adhesives (PSAs) that are of common technical use as adhesive tapes or labels.

  8. Tongue adhesion in the horned frog Ceratophrys sp.

    PubMed

    Kleinteich, Thomas; Gorb, Stanislav N

    2014-06-12

    Frogs are well-known to capture elusive prey with their protrusible and adhesive tongues. However, the adhesive performance of frog tongues and the mechanism of the contact formation with the prey item remain unknown. Here we measured for the first time adhesive forces and tongue contact areas in living individuals of a horned frog (Ceratophrys sp.) against glass. We found that Ceratophrys sp. generates adhesive forces well beyond its own body weight. Surprisingly, we found that the tongues adhered stronger in feeding trials in which the coverage of the tongue contact area with mucus was relatively low. Thus, besides the presence of mucus, other features of the frog tongue (surface profile, material properties) are important to generate sufficient adhesive forces. Overall, the experimental data shows that frog tongues can be best compared to pressure sensitive adhesives (PSAs) that are of common technical use as adhesive tapes or labels.

  9. Tongue adhesion in the horned frog Ceratophrys sp.

    PubMed Central

    Kleinteich, Thomas; Gorb, Stanislav N.

    2014-01-01

    Frogs are well-known to capture elusive prey with their protrusible and adhesive tongues. However, the adhesive performance of frog tongues and the mechanism of the contact formation with the prey item remain unknown. Here we measured for the first time adhesive forces and tongue contact areas in living individuals of a horned frog (Ceratophrys sp.) against glass. We found that Ceratophrys sp. generates adhesive forces well beyond its own body weight. Surprisingly, we found that the tongues adhered stronger in feeding trials in which the coverage of the tongue contact area with mucus was relatively low. Thus, besides the presence of mucus, other features of the frog tongue (surface profile, material properties) are important to generate sufficient adhesive forces. Overall, the experimental data shows that frog tongues can be best compared to pressure sensitive adhesives (PSAs) that are of common technical use as adhesive tapes or labels. PMID:24921415

  10. The need for water quality criteria for frogs.

    PubMed Central

    Boyer, R; Grue, C E

    1995-01-01

    Amphibians are considered reliable indicators of environmental quality. In the western United States, a general decline of frog populations parallels an apparent worldwide decline. The factors thought to be contributing to declines in frog populations include habitat loss, introduction of exotic species, overexploitation, disease, climate change, and decreasing water quality. With respect to water quality, agroecosystems use 80-90% of the water resources in the western United States, frequently resulting in highly eutrophic conditions. Recent investigations suggest that these eutrophic conditions (elevated pH, water temperature, and un-ionized ammonia) may be associated with frog embryo mortality or malformations. However, water quality criteria for frogs and other amphibians do not currently exist. Here, we briefly review data that support the need to develop water quality parameters for frogs in agroecosystems and other habitats. Images Figure 1. Figure 2. Figure 3. Figure 4. A Figure 4. B Figure 5. PMID:7607135

  11. Ovarian dysgerminomas in two mountain chicken frogs (Leptodactylus fallax).

    PubMed

    Fitzgerald, Scott D; Duncan, Ann E; Tabaka, Chris; Garner, Michael M; Dieter, April; Kiupel, Matti

    2007-03-01

    This report describes the gross, histologic, and immunohistochemical features of ovarian dysgerminomas in two adult female mountain chicken frogs (Leptodactylusfallax) from the same zoological institution. One frog was found dead, and the other frog had been ill for several days with a bloated abdomen and lethargy. On necropsy, large, pale multilobulated masses replaced the left ovary in both frogs, and one frog also had numerous smaller nodules scattered throughout the coelomic viscera. Histologically, these masses were composed of sheets and cords of polyhedral discrete germ cells consistent with the diagnosis of dysgerminoma. Neoplastic cells stained positive with immunohistochemistry for Oct4, which has been reported to detect stem cells including germ cells in a variety of species, including humans. Ovarian tumors are uncommonly encountered in both reptiles and amphibians, and this report is the first report of dysgerminoma in any amphibian species.

  12. Debris is not a cheese: litter in coastal Louisiana

    USGS Publications Warehouse

    Lindstedt, Dianne M.; Holmes, Joseph C.

    1989-01-01

    An 18-month study of six Louisiana beaches determined the extent, composition, and possible sources of beach litter. Data showed that from 2590 to 23,154 items may be encountered along any one-mile stretch of Louisiana beach, depending upon location and season, and that densities of litter ranged from 5 to 28 items per 100 m2. Plastics constituted 47% of the total, followed by polystyrene at 16% and glass at 10%. Drink-related items accounted for 40% of the identifiable material; operational wastes, 21%; galley wastes, 15%; personal items, 11%; and fishing items, 6%. Litter laws already exist at state and federal levels. Strict enforcement of Annex V of MARPOL should significantly reduce plastic beach litter. Solutions to beach litter will come from public participation in adopt-a-beach programs and statewide clean-ups and from educational programs focusing on existing laws, proper disposal methods, recycling, and the threat litter poses to wildlife and public health.

  13. Stages of litter transformation in bog birch forests

    NASA Astrophysics Data System (ADS)

    Efremova, T. T.; Avrova, A. F.; Efremov, S. P.; Melent'eva, N. V.

    2009-10-01

    In the litters (peaty, weakly decomposed, and strongly decomposed) of bog birch forests, the biochemical transformation of plant material includes several discrete stages. The best prediction of the decomposition stages is the set of indices characterizing the humus status of the soils: the C/N ratio, (ΣHA + ΣFA)/Cpolysaccharides, and the contents of humic and fulvic acids of fraction 1 in the groups of plant debris of different sizes. The discrimination of the litters according to the level of the biochemical transformation of the organic residues was observed when using the (ΣHA + ΣFA)/Cpolysaccharides ratio, which is 6.3 in the peaty litter and 11.2 and 18.4 in the weakly decomposed and strongly decomposed litters, respectively. The biochemical classification of litters in the bog birch forests is in agreement with the morphological classification of litters.

  14. Soil fauna slow down decomposition of leaf litter

    NASA Astrophysics Data System (ADS)

    Frouz, J.

    2009-04-01

    In one year incubation laboratory experiment, decomposition of alder, oak and willow litter was compared with decomposition of excrements of St marks Fly larvae (Bibio marci), produced from the same liter. Decomposition (amount of CO2 produced) was significantly higher in leas litter than in excrements. Invertebrates affect litter by many ways liter is fragmented mechanically during feeding exposed to alkaline environment and enzymes in the gut and coated by clay mineral during gut passage. In order to explore potential mechanisms that may be responsible for reduction of decomposition process 3 litter treatments with mimic certain aspects of invertebrate influence was prepared: fragmented litter, litter treated by alkaline solution and mixed with clay (kaolinite). Among those treatments Alkalization has the most strong effect on decomposition slow down.

  15. Trace elements in soils fertilized with poultry litter.

    PubMed

    Gupta, G; Charles, S

    1999-12-01

    Poultry litter is used on agricultural land because of its high nutrient content. The litter contains trace elements. With land application of litter, these elements may accumulate in the soil or plants, may be transported as run-off to surface water, or may be leached into groundwater. The objective of this research was to measure the concentrations of trace elements in soils fertilized with poultry litter. Soil was collected from three agricultural farms in Wicomico County, MD. These farms had a long history of poultry litter application. A nitric acid extraction was performed on soil samples collected to a depth of 60 cm. The concentrations of As, Cd, Cu, Mn, Pb, and Zn were determined using atomic absorption spectrophotometry. Arsenic, Cd, Cu, and Mn concentrations were higher in the manured fields than in the control fields. Lead and Zn concentrations did not significantly change with the application of poultry litter.

  16. Changes in poultry litter toxicity with simulated acid rain

    SciTech Connect

    Gupta, G.; Krishnamurthy, S. )

    1991-01-01

    The Delmarva Peninsula on the Eastern Shore of Maryland ranks 4th in the nation in poultry production and generates 9,500 metric tons of poultry manure/litter per day. The poultry litter contains many macro and micro nutrients and is an excellent source of fertilizer. The litter also contains antibiotics, heavy metals, hormones and many microorganisms. Land application of this litter has been the only means of its utilization and disposal. With rainfall, surface water run-off (leachate), from land on which litter has been applied, reaches the Cheasapeake Bay from this region. This leachate with its high organic and inorganic salt contents and high biochemical oxygen demand can severely disrupt the aquatic life and cause fish kills. The objective of this research was to study the effect of simulated acid rain (pH 3, 4 and 5) on the toxicity of poultry litter extracts.

  17. Detritus Quality and Locality Determines Survival and Mass, but Not Export, of Wood Frogs at Metamorphosis

    PubMed Central

    Milanovich, Joseph R.; Barrett, Kyle; Crawford, John A.

    2016-01-01

    Single-site experiments have demonstrated detritus quality in wetlands can have strongly negative, neutral, and even positive influences on wildlife. However, an examination of the influence of detritus quality across several regions is lacking and can provide information on whether impacts from variation in detritus quality are consistent across species with wide ranges. To address this gap in regional studies we examined effects of emergent and allochthonous detritus of different nutrient qualities on amphibians and assessed a mechanism that may contribute to potential impacts. We used aquatic mesocosms to raise wood frogs (Rana sylvatica) from two regions of the United States with whole plants from purple loosestrife (Lythrum salicaria), leaf litter from native hardwood trees, and a mixture of both. We examined several metrics of amphibian fitness and life history, including survival, number of days to metamorphosis, and size at metamorphosis. Further, we quantified whether the effects of detritus type could translate to variation in anuran biomass or standing stock of nitrogen or phosphorus export. Our results show detritus with high nutrient quality (purple loosestrife) negatively influenced survival of wood frogs, but increased size of metamorphic individuals in two different regions of the United States. Despite the decrease in survival, the increase in size of post-metamorphic anurans raised with high quality detritus resulted in anuran biomass and standing stock of N and P export being similar across treatments at both locations. These results further demonstrate the role of plant quality in shaping wetland ecosystem dynamics, and represent the first demonstration that effects are consistent within species across ecoregional boundaries. PMID:27824915

  18. Detritus Quality and Locality Determines Survival and Mass, but Not Export, of Wood Frogs at Metamorphosis.

    PubMed

    Milanovich, Joseph R; Barrett, Kyle; Crawford, John A

    2016-01-01

    Single-site experiments have demonstrated detritus quality in wetlands can have strongly negative, neutral, and even positive influences on wildlife. However, an examination of the influence of detritus quality across several regions is lacking and can provide information on whether impacts from variation in detritus quality are consistent across species with wide ranges. To address this gap in regional studies we examined effects of emergent and allochthonous detritus of different nutrient qualities on amphibians and assessed a mechanism that may contribute to potential impacts. We used aquatic mesocosms to raise wood frogs (Rana sylvatica) from two regions of the United States with whole plants from purple loosestrife (Lythrum salicaria), leaf litter from native hardwood trees, and a mixture of both. We examined several metrics of amphibian fitness and life history, including survival, number of days to metamorphosis, and size at metamorphosis. Further, we quantified whether the effects of detritus type could translate to variation in anuran biomass or standing stock of nitrogen or phosphorus export. Our results show detritus with high nutrient quality (purple loosestrife) negatively influenced survival of wood frogs, but increased size of metamorphic individuals in two different regions of the United States. Despite the decrease in survival, the increase in size of post-metamorphic anurans raised with high quality detritus resulted in anuran biomass and standing stock of N and P export being similar across treatments at both locations. These results further demonstrate the role of plant quality in shaping wetland ecosystem dynamics, and represent the first demonstration that effects are consistent within species across ecoregional boundaries.

  19. Effects of a glyphosate-based herbicide on the development of Common toads (Bufo bufo L.; Amphibia) at different temperatures

    NASA Astrophysics Data System (ADS)

    Baier, Fabian; Gruber, Edith; Spangl, Bernhard; Zaller, Johann G.

    2016-04-01

    Herbicides based on the active ingredient glyphosate are frequently applied in agriculture, horticulture and private gardens all over the world. Recently, leaching of glyphosate or its metabolite (AMPA) into water bodies inhabited by amphibians has been reported. However, very little is known about non-target effects of these herbicides on amphibians and even less is known to what extent different temperatures might alter these effects. Using climate chambers, we investigated the effects of the glyphosate-based herbicide Roundup PowerFlex® (480 g L-1 glyphosate, formulated as 588 g L-1 potassium salt) on the larval development of Common toads (Bufo bufo L.; Amphibia: Anura) under different temperature regimes (15°C vs. 20°C). We established five herbicide concentrations: 0, 1.5, 3, 4 mg acid equivalent L-1 and a 4 mg a.e. L-1 pulse treatment (totally three applications of 1.5, 1.5 and another 1 mg a.e. L-1) at each temperature in a full-factorial design. Each treatment combination was replicated five times, the experiment ran for 24 days. Results showed a highly significant effect of temperature on body length and body width but no effect of herbicide concentration on these growth parameters. Moreover, highly significant interactions between herbicide and temperature on body length and body width were observed suggesting that herbicides had different effects on different temperatures. In conclusion, although Roundup PowerFlex® at the tested concentrations appeared to have no acute toxicity to larvae of Common toads, the observed effects on tadpole morphology will potentially affect competitive interactions in spawning ponds of amphibia. Our findings of herbicide x temperature interactions might become more prevalent when human-induced climate change will lead to more extreme temperatures.

  20. Immunohistochemical localization of insulin-like growth factor I and II in the endocrine pancreas of birds, reptiles, and amphibia.

    PubMed

    Reinecke, M; Broger, I; Brun, R; Zapf, J; Maake, C

    1995-12-01

    Immunoreactive insulin-like growth factors I and II (IGF-I, IGF-II) were sought in the endocrine pancreas of representative birds, reptiles, and amphibia using antisera specific for mammalian IGF-I and IGF-II and the classical islet hormones insulin (INS), glucagon (GLUC), somatostatin (SOM), and pancreatic polypeptide (PP) in double immunofluorescence. Both IGF-I and IGF-II immunoreactivities were present in the endocrine pancreas of all species. IGF-II immunoreactivity was exclusively found in INS-immunoreactive (-IR) cells, indicating evolutionary conservation of the islet IGF-II system. In contrast, IGF-I immunoreactivity was distributed differently among the species and never occurred in INS-IR cells. In the anuran Xenopus laevis, IGF-I immunoreactivity was present in islet cells showing coexistence of GLUC and PP immunoreactivities. In reptiles, the lizards (Lacerta viridis, Scincus officinalis) exhibited IGF-I immunoreactivity in PP-IR and SOM-IR cells and the snakes (Psamophis leniolatum, Coluber ravergieri) in SOM-IR and GLUC-IR cells. In birds, IGF-I immunoreactivity was located either in SOM-IR cells only (Gallus g. domesticus, Streptopelia roseogrisea) or in PP-IR and SOM-IR cells (Coturnix c. japonica). Thus, the distribution patterns of islet IGF-I immunoreactivities in birds, reptiles, and amphibia are equivalent to those in mammals and most bony fish. They differ, however, from those found in cartilaginous fish, cyclostomes, and protochordates, where a total or partial coexistence of IGF-I and INS immunoreactivities has been obtained. Therefore, the divergence of IGF-I and INS seems to have occurred early in vertebrate phylogeny. Furthermore, the existence of IGF-I immunoreactivity likely is common in the islets of all vertebrates. Finally, no phylogenetic trend to concentrate IGF-I immunoreactivity in a particular islet cell type is apparent.

  1. Pathogenesis of Frog Virus 3 ( Ranavirus, Iridoviridae) Infection in Wood Frogs ( Rana sylvatica).

    PubMed

    Forzán, M J; Jones, K M; Ariel, E; Whittington, R J; Wood, J; Markham, R J Frederick; Daoust, P-Y

    2017-01-01

    Wood frogs ( Rana sylvatica) are highly susceptible to infection with Frog virus 3 (FV3, Ranavirus, Iridoviridae), a cause of mass mortality in wild populations. To elucidate the pathogenesis of FV3 infection in wood frogs, 40 wild-caught adults were acclimated to captivity, inoculated orally with a fatal dose of 10(4.43) pfu/frog, and euthanized at 0.25, 0.5, 1, 2, 4, 9, and 14 days postinfection (dpi). Mild lesions occurred sporadically in the skin (petechiae) and bone marrow (necrosis) during the first 2 dpi. Severe lesions occurred 1 to 2 weeks postinfection and consisted of necrosis of medullary and extramedullary hematopoietic tissue, lymphoid tissue in spleen and throughout the body, and epithelium of skin, mucosae, and renal tubules. Viral DNA was first detected (polymerase chain reaction) in liver at 4 dpi; by dpi 9 and 14, all viscera tested (liver, kidney, and spleen), skin, and feces were positive. Immunohistochemistry (IHC) first detected viral antigen in small areas devoid of histologic lesions in the oral mucosa, lung, and colon at 4 dpi; by 9 and 14 dpi, IHC labeling of viral antigen associated with necrosis was found in multiple tissues. Based on IHC staining intensity and lesion severity, the skin, oral, and gastrointestinal epithelium and renal tubular epithelium were important sites of viral replication and shedding, suggesting that direct contact (skin) and fecal-oral contamination are effective routes of transmission and that skin tissue, oral, and cloacal swabs may be appropriate antemortem diagnostic samples in late stages of disease (>1 week postinfection) but poor samples to detect infection in clinically healthy frogs.

  2. Fungal contamination of poultry litter: a public health problem.

    PubMed

    Viegas, C; Carolino, E; Malta-Vacas, J; Sabino, R; Viegas, S; Veríssimo, C

    2012-01-01

    Although numerous studies have been conducted on microbial contaminants associated with various stages related to poultry and meat products processing, only a few reported on fungal contamination of poultry litter. The goals of this study were to (1) characterize litter fungal contamination and (2) report the incidence of keratinophilic and toxigenic fungi presence. Seven fresh and 14 aged litter samples were collected from 7 poultry farms. In addition, 27 air samples of 25 litters were also collected through impaction method, and after laboratory processing and incubation of collected samples, quantitative colony-forming units (CFU/m³) and qualitative results were obtained. Twelve different fungal species were detected in fresh litter and Penicillium was the most frequent genus found (59.9%), followed by Alternaria (17.8%), Cladosporium (7.1%), and Aspergillus (5.7%). With respect to aged litter, 19 different fungal species were detected, with Penicillium sp. the most frequently isolated (42.3%), followed by Scopulariopsis sp. (38.3%), Trichosporon sp. (8.8%), and Aspergillus sp. (5.5%). A significant positive correlation was found between litter fungal contamination (CFU/g) and air fungal contamination (CFU/m³). Litter fungal quantification and species identification have important implications in the evaluation of potential adverse health risks to exposed workers and animals. Spreading of poultry litter in agricultural fields is a potential public health concern, since keratinophilic (Scopulariopsis and Fusarium genus) as well as toxigenic fungi (Aspergillus, Fusarium, and Penicillium genus) were isolated.

  3. Functionally dissimilar neighbors accelerate litter decomposition in two grass species.

    PubMed

    Barbe, Lou; Jung, Vincent; Prinzing, Andreas; Bittebiere, Anne-Kristel; Butenschoen, Olaf; Mony, Cendrine

    2017-02-16

    Plant litter decomposition is a key regulator of nutrient recycling. In a given environment, decomposition of litter from a focal species depends on its litter quality and on the efficiency of local decomposers. Both may be strongly modified by functional traits of neighboring species, but the consequences for decomposition of litter from the focal species remain unknown. We tested whether decomposition of a focal plant's litter is influenced by the functional-trait dissimilarity to the neighboring plants. We cultivated two grass species (Brachypodium pinnatum and Elytrigia repens) in experimental mesocosms with functionally similar and dissimilar neighborhoods, and reciprocally transplanted litter. For both species, litter quality increased in functionally dissimilar neighborhoods, partly as a result of changes in functional traits involved in plant-plant interactions. Furthermore, functional dissimilarity increased overall decomposer efficiency in one species, probably via complementarity effects. Our results suggest a novel mechanism of biodiversity effects on ecosystem functioning in grasslands: interspecific functional diversity within plant communities can enhance intraspecific contributions to litter decomposition. Thus, plant species might better perform in diverse communities by benefiting from higher remineralization rates of their own litter.

  4. Marine litter in the Nordic Seas: Distribution composition and abundance.

    PubMed

    Buhl-Mortensen, Lene; Buhl-Mortensen, Pål

    2017-08-23

    Litter has been found in all marine environments and is accumulating in seabirds and mammals in the Nordic Seas. These ecosystems are under pressure from climatic change and fisheries while the human population is small. The marine landscapes in the area range from shallow fishing banks to deep-sea canyons. We present density, distribution and composition of litter from the first large-scale mapping of sea bed litter in arctic and subarctic waters. Litter was registered from 1778 video transects, of which 27% contained litter. The background density of litter in the Barents Sea and Norwegian Sea is 202 and 279 items/km(2) respectively, and highest densities were found close to coast and in canyons. Most of the litter originated from the fishing industry and plastic was the second most common litter. Background levels were comparable to European records and areas with most littering had higher densities than in Europe. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. The response of Rana muscosa, the mountain yellow-legged frog, to short distance translocations.

    Treesearch

    K. R. Matthews

    2003-01-01

    ABSTRACT.—To determine the response of Mountain Yellow-Legged Frogs to short distance translocations, I placed transmitters on 20 adult frogs and moved them short distances from 144–630 m and monitored their responses for up to 30 days. Of the 20 translocated frogs, seven frogs returned to their original capture site, four frogs moved in the direction of their capture...

  6. A new species of Meristogenys (Amphibia, Anura, Ranidae) from Sabah, Borneo.

    PubMed

    Matsui, Masafumi; Shimada, Tomohiko; Sudin, Ahmad

    2010-01-01

    We describe a new species of torrent-dwelling ranid frog of the genus Meristogenys from the Crocker Range, western Sabah, northern Borneo. The new species, Meristogenys maryatiae, differs from congeners by the combination of: small body, males 31-37 mm and females 65-66 mm in snout-vent length; head narrower than long; eyes moderate, diameter subequal to snout; iris unicolored; legs long; ventral surface of tibia without heavy pigmentation; rear of thigh blotched dark brown and cream; toes fully webbed; outer metatarsal tubercle present; larval dental formula 7(4-7)/6(1).

  7. Spontaneous mechanical activity in depolarized frog ventricle

    PubMed Central

    1976-01-01

    Spontaneous mechanical activity can be produced in depolarized frog ventricle by bathing the tissue in a solution with low Na, Iow Ca, and high K+. The contractions can be inhibited by depleting the tissue of Ca first, but they are relatively insensitive to changes in either extracellular [Ca++] or [Ca++]/[Na+]2. They are terminated very rapidly by raising [Na+] to 40 mM. Local anesthetics enhance the spontaneous activity in proportion to the concentration of their free base form. These contractions occur relatively rhythmically for several hours. Since the preparation is multicellular, this suggests a mechanism for intercellular communication without change in membrane potential. PMID:822122

  8. Global patterns in litter decomposition: a synthesis.

    NASA Astrophysics Data System (ADS)

    Auch, W. E.; Ross, D. S.

    2007-12-01

    Leaf and coarse woody debris (LCWD) decay catalyzes the biochemical mechanisms of the soil-aboveground interface, and should be an important component of climate change models that address carbon and nitrogen. There is a clear need for the identification of determinant climate or litter chemistry parameters at the global scale. Local and global decay is commonly attributed to litter chemistry and climate, respectively. The objective of this synthesis was to illustrate LCWD decay across a global climate-chemistry continuum and contrast results with a previous assessment via both standard first-order (|k|) decay kinetics and gradient exponent values arranged in order of influence from initial to latter decay stages. Results suggest greater initial LCWD cation concentrations yielded the fastest initial rates of decomposition and most climatic indices appeared relevant at intermediate stages of decay. Elevation and refractory LCWD carbon (i.e. carbon, lignin, and tannins) were inversely correlated with decay, prolonging the process and possibly acting in concert as "end-point" determinants. Furthermore, the initial influence of nitrogen and phosphorus is universal across LCWD-type as well as ecoregion. Climate acts in a transitional role between easily solubilized and late or aromatic substrate decay. Global and continental carbon cycling assumptions and models must acknowledge: i) the influence of LCWD cation and N concentration during initial fragmentation, leaching, and transformation; ii) climate, specifically seasonal temperature averages > evapotranspiration > precipitation, during the interim; and iii) the ever-present influence of seasonality and litter aromatic components. Key Words: Leaf and Coarse Woody Debris (LCWD) decomposition, |k|, first-order kinetics, Carbon Cycle, Global Climate Change (GCC), Actual Evapotranspiration (AET).

  9. Effect of Litter Amendments on Poultry Litter Microbial Communities and the Subsequent Effect on Nitrogen Dynamics

    USDA-ARS?s Scientific Manuscript database

    Ammonia production in poultry houses has serious implications for flock health and performance, nutrient value of poultry litter, and energy costs for running poultry operations. Numerous amendments are available for reducing ammonia volatilization, with acidifier-types being the most prevalent due ...

  10. Effects of chemically amended litter on broiler performances, atmospheric ammonia concentration, and phosphorus solubility in litter.

    PubMed

    Do, J C; Choi, I H; Nahm, K H

    2005-05-01

    The effects of 6 different litter amendments on broiler performance, level of atmospheric ammonia (NH3) concentration, and soluble reactive phosphorus (SRP) in litter was determined. Through 3 experiments conducted on 2 different commercial farms, one chemical amendment was added to the litter and then was compared with a control. Broiler performance was not affected by any of the amendments except the ferrous sulfate amendment for which mortality was 25.5%. Application of aluminum chloride (AlCl3 x 6H2O) to the litter lowered atmospheric ammonia concentrations at 42 d by 97.2%, whereas ferrous sulfate (FeSO4 x 7H2O) lowered it by 90.77%. Ammonia concentrations were reduced by 86.18, 78.66, 75.52, and 69.00% by aluminum sulfate [alum or Al2(SO4)3 x 14H2O)], alum + CaCO3, aluminum chloride + CaCO3, and potassium permanganate (KMnO4), respectively, when compared with each control at 42 d. Each amendment except KMnO4 significantly reduced SRP contents. Alum and aluminum chloride were the effective compounds evaluated on the commercial farms with respect to reducing ammonia contents, phosphorus solubility, and mortality.

  11. Efficacy of Activated Carbon from Broiler Litter in the Removal of Litter Generated Ammonia

    USDA-ARS?s Scientific Manuscript database

    Over the past 10 years, the production of broilers has increased by 29 percent to approximately 9 billion in 2005. Ammonia (NH3) pollution from broiler excreta is a primary concern for industry viability which requires innovative treatment options. This research focused on the use of broiler litter ...

  12. Efffacy of activated carbon from broiler litter in the removal of litter generated ammonia

    USDA-ARS?s Scientific Manuscript database

    Over the past 10 years, the production of broilers has increased by 29 percent to approximately 9 billion in 2005. Ammonia (NH3) pollution from broiler excreta is a primary concern for industry viability. The consequent rise in the manure/litter production rates requires innovative treatment optio...

  13. Amino compounds in poultry litter, litter-amended pasture soils and grass shoots

    USDA-ARS?s Scientific Manuscript database

    Organic N accounts for 95-98% of total soil N contents with amino compounds (ACs) as major ingredients. But relatively little is known about the effects of poultry litter (PL) application on soil AC pools and turnover. In this work, we determined 21 AC contents in 23 PL samples, 15 soil samples with...

  14. Amino Compounds in Poultry Litter, Litter-Amended Soil and Plants

    USDA-ARS?s Scientific Manuscript database

    Amino acids and amino sugars generally constitute the bulk of N in soil, so understanding their cycling is critical for efficient N use in crop production. Although poultry litter (PL) is relatively rich in N, little is known about the effects of PL application on turnover and availability of amino...

  15. Fenbendazole treatment and litter size in rats.

    PubMed

    Johnston, Nancy A; Bieszczak, Jeremiah R; Verhulst, Steven; Disney, Kimberly E; Montgomery, Kyle E; Toth, Linda A

    2006-11-01

    Fenbendazole is commonly used in laboratory animal medicine as an anthelmintic for elimination of pinworms. It is generally regarded as a safe drug with minimal side effects. In our facility, 2 breeding colonies of rats were treated with fenbendazole to eliminate pinworms. Analysis of the breeding records revealed that feeding Sprague-Dawley rats a diet containing fenbendazole on a continuous basis for 7 consecutive weeks was associated with a significant reduction in litter size. Although the mechanism underlying this effect is unknown, the finding prompts caution when using fenbendazole to treat valuable breeding colonies or strains that are poor breeders.

  16. WETLAND INVERTEBRATE COMMUNITY RESPONSES TO VARYING EMERGENT LITTER IN A PRAIRIE POTHOLE EMERGENT MARSH

    EPA Science Inventory

    Plant litter produced in the interior of dense emergent stands may directly or indirectly influence invertebrate communities. Low litter may provide structure and refuge to invertebrates while high litter may shade out vegetation and algae and decrease oxygen concentrations. With...

  17. WETLAND INVERTEBRATE COMMUNITY RESPONSES TO VARYING EMERGENT LITTER IN A PRAIRIE POTHOLE EMERGENT MARSH

    EPA Science Inventory

    Plant litter produced in the interior of dense emergent stands may directly or indirectly influence invertebrate communities. Low litter may provide structure and refuge to invertebrates while high litter may shade out vegetation and algae and decrease oxygen concentrations. With...

  18. ESTIMATING THE BREAKDOWN AND ACCUMULATION OF EMERGENT MACROPHYTE LITTER: A MASS-BALANCE APPROACH

    EPA Science Inventory

    Litter accumulation within emergent macrophyte marshes may significantly influence abiotic conditions and biota but litter is rarely considered in emergent macrophyte studies. Litter is defined here as the standing and fallen dead plant material that can be collected using harv...

  19. ESTIMATING THE BREAKDOWN AND ACCUMULATION OF EMERGENT MACROPHYTE LITTER: A MASS-BALANCE APPROACH

    EPA Science Inventory

    Litter accumulation within emergent macrophyte marshes may significantly influence abiotic conditions and biota but litter is rarely considered in emergent macrophyte studies. Litter is defined here as the standing and fallen dead plant material that can be collected using harv...

  20. Long-term litter decomposition controlled by manganese redox cycling

    DOE PAGES

    Keiluweit, Marco; Nico, Peter S.; Harmon, Mark; ...

    2015-09-08

    Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors. However, a strong correlation has been observed between the manganese (Mn) content of litter and decomposition rates across a variety of forest ecosystems. Here, we show that long-term litter decomposition in forest ecosystems is tightly coupled to Mn redox cycling. Over 7 years of litter decomposition, microbial transformation of littermore » was paralleled by variations in Mn oxidation state and concentration. A detailed chemical imaging analysis of the litter revealed that fungi recruit and redistribute unreactive Mn2+ provided by fresh plant litter to produce oxidative Mn3+ species at sites of active decay, with Mn eventually accumulating as insoluble Mn3+/4+ oxides. Formation of reactive Mn3+ species coincided with the generation of aromatic oxidation products, providing direct proof of the previously posited role of Mn3+-based oxidizers in the breakdown of litter. Our results suggest that the litter-decomposing machinery at our coniferous forest site depends on the ability of plants and microbes to supply, accumulate, and regenerate short-lived Mn3+ species in the litter layer. As a result, this observation indicates that biogeochemical constraints on bioavailability, mobility, and reactivity of Mn in the plant–soil system may have a profound impact on litter decomposition rates.« less

  1. The gastrocoel roof plate in embryos of different frogs.

    PubMed

    Sáenz-Ponce, Natalia; Santillana-Ortiz, Juan-Diego; del Pino, Eugenia M

    2012-02-01

    The morphology of the gastrocoel roof plate and the presence of cilia in this structure were examined in embryos of four species of frogs. Embryos of Ceratophrys stolzmanni (Ceratophryidae) and Engystomops randi (Leiuperidae) develop rapidly, provide comparison for the analysis of gastrocoel roof plate development in the slow-developing embryos of Epipedobates machalilla (Dendrobatidae) and Gastrotheca riobambae (Hemiphractidae). Embryos of the analyzed frogs develop from eggs of different sizes, and display different reproductive and developmental strategies. In particular, dorsal convergence and extension and archenteron elongation begin during gastrulation in embryos of rapidly developing frogs, as in Xenopus laevis. In contrast, cells that involute during gastrulation are stored in the large circumblastoporal collar that develops around the closed blastopore in embryos of slow-developing frogs. Dorsal convergence and extension only start after blastopore closure in slow-developing frog embryos. However, in the neurulae, a gastrocoel roof plate develops, despite the accumulation of superficial mesodermal cells in the circumblastoporal collar. Embryos of all four species develop a ciliated gastrocoel roof plate at the beginning of neurulation. Accordingly, fluid-flow across the gastrocoel roof plate is likely the mechanism of left-right asymmetry patterning in these frogs, as in X. laevis and other vertebrates. A ciliated gastrocoel roof plate, with a likely origin as superficial mesoderm, is conserved in frogs belonging to four different families and with different modes of gastrulation.

  2. Peatlands and green frogs: A relationship regulated by acidity?

    USGS Publications Warehouse

    Mazerolle, M.J.

    2005-01-01

    The effects of site acidification on amphibian populations have been thoroughly addressed in the last decades. However, amphibians in naturally acidic environments, such as peatlands facing pressure from the peat mining industry, have received little attention. Through two field studies and an experiment, I assessed the use of bog habitats by the green frog (Rana clamitans melanota), a species sensitive to various forestry and peat mining disturbances. First, I compared the occurrence and breeding patterns of frogs in bog and upland ponds. I then evaluated frog movements between forest and bog habitats to determine whether they corresponded to breeding or postbreeding movements. Finally, I investigated, through a field experiment, the value of bogs as rehydrating areas for amphibians by offering living Sphagnum moss and two media associated with uplands (i.e., water with pH ca 6.5 and water-saturated soil) to acutely dehydrated frogs. Green frog reproduction at bog ponds was a rare event, and no net movements occurred between forest and bog habitats. However, acutely dehydrated frogs did not avoid Sphagnum. Results show that although green frogs rarely breed in bogs and do not move en masse between forest and bog habitats, they do not avoid bog substrates for rehydrating, despite their acidity. Thus, bogs offer viable summering habitat to amphibians, which highlights the value of these threatened environments in terrestrial amphibian ecology.

  3. Landing on branches in the frog Trachycephalus resinifictrix (Anura: Hylidae).

    PubMed

    Bijma, Nienke N; Gorb, Stanislav N; Kleinteich, Thomas

    2016-04-01

    Frogs (Lissamphibia: Anura) are famous for their saltatory or hopping locomotion, which is related to numerous anatomical specialisations that are characteristic for the group. However, while the biomechanics of take-off in frogs have been studied in detail, much less is known on how frogs land after a jump. Besides terrestrial and aquatic species, several lineages of frogs adopted an arboreal lifestyle and especially the biomechanics of landing on challenging, small, and unpredictable substrates, such as leaves or branches, are virtually unknown. Here we studied the landing kinematics of the arboreal frog Trachycephalus resinifictrix (Hylidae) on a wooden stick that was used to mimic a small tree branch. We observed two different landing behaviours: (1) landing on the abdomen and (2) attachment with the toes of either the forelimb or the hindlimb. In the latter case, the frogs performed a cartwheel around the stick, while they were only attached by their adhesive toe pads. We estimated the forces that act on the toes during this behaviour to be up to fourteen times the body weight of the animals. This behaviour demonstrates the remarkable adhesive capabilities of the toe pads and the body control of the frogs.

  4. Interacting microbe and litter quality controls on litter decomposition: a modeling analysis.

    PubMed

    Moorhead, Daryl; Lashermes, Gwenaëlle; Recous, Sylvie; Bertrand, Isabelle

    2014-01-01

    The decomposition of plant litter in soil is a dynamic process during which substrate chemistry and microbial controls interact. We more clearly quantify these controls with a revised version of the Guild-based Decomposition Model (GDM) in which we used a reverse Michaelis-Menten approach to simulate short-term (112 days) decomposition of roots from four genotypes of Zea mays that differed primarily in lignin chemistry. A co-metabolic relationship between the degradation of lignin and holocellulose (cellulose+hemicellulose) fractions of litter showed that the reduction in decay rate with increasing lignin concentration (LCI) was related to the level of arabinan substitutions in arabinoxylan chains (i.e., arabinan to xylan or A∶X ratio) and the extent to which hemicellulose chains are cross-linked with lignin in plant cell walls. This pattern was consistent between genotypes and during progressive decomposition within each genotype. Moreover, decay rates were controlled by these cross-linkages from the start of decomposition. We also discovered it necessary to divide the Van Soest soluble (labile) fraction of litter C into two pools: one that rapidly decomposed and a second that was more persistent. Simulated microbial production was consistent with recent studies suggesting that more rapidly decomposing materials can generate greater amounts of potentially recalcitrant microbial products despite the rapid loss of litter mass. Sensitivity analyses failed to identify any model parameter that consistently explained a large proportion of model variation, suggesting that feedback controls between litter quality and microbial activity in the reverse Michaelis-Menten approach resulted in stable model behavior. Model extrapolations to an independent set of data, derived from the decomposition of 12 different genotypes of maize roots, averaged within <3% of observed respiration rates and total CO2 efflux over 112 days.

  5. Interacting Microbe and Litter Quality Controls on Litter Decomposition: A Modeling Analysis

    PubMed Central

    Moorhead, Daryl; Lashermes, Gwenaëlle; Recous, Sylvie; Bertrand, Isabelle

    2014-01-01

    The decomposition of plant litter in soil is a dynamic process during which substrate chemistry and microbial controls interact. We more clearly quantify these controls with a revised version of the Guild-based Decomposition Model (GDM) in which we used a reverse Michaelis-Menten approach to simulate short-term (112 days) decomposition of roots from four genotypes of Zea mays that differed primarily in lignin chemistry. A co-metabolic relationship between the degradation of lignin and holocellulose (cellulose+hemicellulose) fractions of litter showed that the reduction in decay rate with increasing lignin concentration (LCI) was related to the level of arabinan substitutions in arabinoxylan chains (i.e., arabinan to xylan or A∶X ratio) and the extent to which hemicellulose chains are cross-linked with lignin in plant cell walls. This pattern was consistent between genotypes and during progressive decomposition within each genotype. Moreover, decay rates were controlled by these cross-linkages from the start of decomposition. We also discovered it necessary to divide the Van Soest soluble (labile) fraction of litter C into two pools: one that rapidly decomposed and a second that was more persistent. Simulated microbial production was consistent with recent studies suggesting that more rapidly decomposing materials can generate greater amounts of potentially recalcitrant microbial products despite the rapid loss of litter mass. Sensitivity analyses failed to identify any model parameter that consistently explained a large proportion of model variation, suggesting that feedback controls between litter quality and microbial activity in the reverse Michaelis-Menten approach resulted in stable model behavior. Model extrapolations to an independent set of data, derived from the decomposition of 12 different genotypes of maize roots, averaged within <3% of observed respiration rates and total CO2 efflux over 112 days. PMID:25264895

  6. Non-Native Plant Litter Enhances Soil Carbon Dioxide Emissions in an Invaded Annual Grassland

    PubMed Central

    Zhang, Ling; Wang, Hong; Zou, Jianwen; Rogers, William E.; Siemann, Evan

    2014-01-01

    Litter decomposition is a fundamental ecosystem process in which breakdown and decay of plant detritus releases carbon and nutrients. Invasive exotic plants may produce litter that differs from native plant litter in quality and quantity. Such differences may impact litter decomposition and soil respiration in ways that depend on whether exotic and native plant litters decompose in mixtures. However, few field experiments have examined how exotic plants affect soil respiration via litter decomposition. Here, we conducted an in situ study of litter decomposition of an annual native grass (Eragrostis pilosa), a perennial exotic forb (Alternanthera philoxeroides), and their mixtures in an annual grassland in China to examine potential invasion effects on soil respiration. Alternanthera litter decomposed faster than Eragrostis litter when each was incubated separately. Mass loss in litter mixes was more rapid than predicted from rates in single species bags (only 35% of predicted mass remained at 8 months) showing synergistic effects. Notably, exotic plant litter decomposition rate was unchanged but native plant litter decomposition rate was accelerated in mixtures (decay constant k = 0.20 month−1) compared to in isolation (k = 0.10 month−1). On average, every litter type increased soil respiration compared to bare soil from which litter was removed. However, the increases were larger for mixed litter (1.82 times) than for Alternanthera litter (1.58 times) or Eragrostis litter (1.30 times). Carbon released as CO2 relative to litter carbon input was also higher for mixed litter (3.34) than for Alternathera litter (2.29) or Eragrostis litter (1.19). Our results indicated that exotic Alternanthera produces rapidly decomposing litter which also accelerates the decomposition of native plant litter in litter mixtures and enhances soil respiration rates. Thus, this exotic invasive plant species will likely accelerate carbon cycling and increase soil respiration

  7. Non-native plant litter enhances soil carbon dioxide emissions in an invaded annual grassland.

    PubMed

    Zhang, Ling; Wang, Hong; Zou, Jianwen; Rogers, William E; Siemann, Evan

    2014-01-01

    Litter decomposition is a fundamental ecosystem process in which breakdown and decay of plant detritus releases carbon and nutrients. Invasive exotic plants may produce litter that differs from native plant litter in quality and quantity. Such differences may impact litter decomposition and soil respiration in ways that depend on whether exotic and native plant litters decompose in mixtures. However, few field experiments have examined how exotic plants affect soil respiration via litter decomposition. Here, we conducted an in situ study of litter decomposition of an annual native grass (Eragrostis pilosa), a perennial exotic forb (Alternanthera philoxeroides), and their mixtures in an annual grassland in China to examine potential invasion effects on soil respiration. Alternanthera litter decomposed faster than Eragrostis litter when each was incubated separately. Mass loss in litter mixes was more rapid than predicted from rates in single species bags (only 35% of predicted mass remained at 8 months) showing synergistic effects. Notably, exotic plant litter decomposition rate was unchanged but native plant litter decomposition rate was accelerated in mixtures (decay constant k = 0.20 month(-1)) compared to in isolation (k = 0.10 month(-1)). On average, every litter type increased soil respiration compared to bare soil from which litter was removed. However, the increases were larger for mixed litter (1.82 times) than for Alternanthera litter (1.58 times) or Eragrostis litter (1.30 times). Carbon released as CO2 relative to litter carbon input was also higher for mixed litter (3.34) than for Alternathera litter (2.29) or Eragrostis litter (1.19). Our results indicated that exotic Alternanthera produces rapidly decomposing litter which also accelerates the decomposition of native plant litter in litter mixtures and enhances soil respiration rates. Thus, this exotic invasive plant species will likely accelerate carbon cycling and increase soil respiration

  8. Leptodactylus ocellatus (Amphibia): mechanism of defense in the skin and molecular phylogenetic relationships.

    PubMed

    Leite, João Manoel Almeida; Silva, Luciano Paulino; Silva-Leite, Roberta Rocha; Ferrari, Ana Stella; Noronha, Sergio Eustáquio; Silva, Helio Ricardo; Bloch, Carlos; Leite, José Roberto de Souza de Almeida

    2010-01-01

    Amphibian antimicrobial peptides have been known for many decades and several of them have already been isolated. However, the number of species investigated is still small. Herein, we report on the skin secretions of Leptodactylus ocellatus, which were extracted by mild electrical stimulation and its semi-preparative reverse-phase chromatography was resolved in more than 30 fractions. Among these fractions, two novel antimicrobial peptides were isolated and their amino acid sequences determined by de novo sequencing. The ocellatins-5 and -6 (21 and 22 amino acid residues, respectively) are amidated at the C-terminus. Ocellatins inhibited the growth of reference strains of both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) with minimal inhibition concentration values in the range of 32-128 microg/mL. The amino acid sequence of the peptides shows structural similarity with members of the antimicrobial peptides found in the skin secretion of other leptodactylid frogs. This observation is consistent with the hypothesis that many frog skin antimicrobial peptides are related evolutionarily, having arisen from multiple duplications of an ancestral gene that existed before the radiation of the different species. (c) 2009 Wiley-Liss, Inc.

  9. Active control of ultrasonic hearing in frogs.

    PubMed

    Gridi-Papp, Marcos; Feng, Albert S; Shen, Jun-Xian; Yu, Zu-Lin; Rosowski, John J; Narins, Peter M

    2008-08-05

    Vertebrates can modulate the sound levels entering their inner ears in the face of intense external sound or during their own vocalizations. Middle ear muscle contractions restrain the motion of the middle ear ossicles, attenuating the transmission of low-frequency sound and thereby protecting the hair cells in the inner ear. Here we show that the Chinese concave-eared torrent frog, Odorrana tormota, can tune its ears dynamically by closing its normally open Eustachian tubes. Contrary to the belief that the middle ear in frogs permanently communicates with the mouth, O. tormota can close this connection by contraction of the submaxillary and petrohyoid muscles, drastically reducing the air volume behind the eardrums. Mathematical modeling and laser Doppler vibrometry revealed that the reduction of this air volume increases the middle ear impedance, resulting in an up to 20 dB gain in eardrum vibration at high frequencies (10-32 kHz) and 26 dB attenuation at low frequencies (3-10 kHz). Eustachian tube closure was observed in the field during calling and swallowing. Besides a potential role in protecting the inner ear from intense low-frequency sound and high buccal air pressure during calling, this previously unrecognized vertebrate mechanism may unmask the high-frequency calls of this species from the low-frequency stream noise which dominates the environment. This mechanism also protects the thin tympanic membranes from injury during swallowing of live arthropod prey.

  10. How frog embryos replicate their DNA reliably

    NASA Astrophysics Data System (ADS)

    Bechhoefer, John; Marshall, Brandon

    2007-03-01

    Frog embryos contain three billion base pairs of DNA. In early embryos (cycles 2-12), DNA replication is extremely rapid, about 20 min., and the entire cell cycle lasts only 25 min., meaning that mitosis (cell division) takes place in about 5 min. In this stripped-down cell cycle, there are no efficient checkpoints to prevent the cell from dividing before its DNA has finished replication - a disastrous scenario. Even worse, the many origins of replication are laid down stochastically and are also initiated stochastically throughout the replication process. Despite the very tight time constraints and despite the randomness introduced by origin stochasticity, replication is extremely reliable, with cell division failing no more than once in 10,000 tries. We discuss a recent model of DNA replication that is drawn from condensed-matter theories of 1d nucleation and growth. Using our model, we discuss different strategies of replication: should one initiate all origins as early as possible, or is it better to hold back and initiate some later on? Using concepts from extreme-value statistics, we derive the distribution of replication times given a particular scenario for the initiation of origins. We show that the experimentally observed initiation strategy for frog embryos meets the reliability constraint and is close to the one that requires the fewest resources of a cell.

  11. Active control of ultrasonic hearing in frogs

    PubMed Central

    Gridi-Papp, Marcos; Feng, Albert S.; Shen, Jun-Xian; Yu, Zu-Lin; Rosowski, John J.; Narins, Peter M.

    2008-01-01

    Vertebrates can modulate the sound levels entering their inner ears in the face of intense external sound or during their own vocalizations. Middle ear muscle contractions restrain the motion of the middle ear ossicles, attenuating the transmission of low-frequency sound and thereby protecting the hair cells in the inner ear. Here we show that the Chinese concave-eared torrent frog, Odorrana tormota, can tune its ears dynamically by closing its normally open Eustachian tubes. Contrary to the belief that the middle ear in frogs permanently communicates with the mouth, O. tormota can close this connection by contraction of the submaxillary and petrohyoid muscles, drastically reducing the air volume behind the eardrums. Mathematical modeling and laser Doppler vibrometry revealed that the reduction of this air volume increases the middle ear impedance, resulting in an up to 20 dB gain in eardrum vibration at high frequencies (10–32 kHz) and 26 dB attenuation at low frequencies (3–10 kHz). Eustachian tube closure was observed in the field during calling and swallowing. Besides a potential role in protecting the inner ear from intense low-frequency sound and high buccal air pressure during calling, this previously unrecognized vertebrate mechanism may unmask the high-frequency calls of this species from the low-frequency stream noise which dominates the environment. This mechanism also protects the thin tympanic membranes from injury during swallowing of live arthropod prey. PMID:18658240

  12. Amphibian pathogens in Southeast Asian frog trade.

    PubMed

    Gilbert, Martin; Bickford, David; Clark, Leanne; Johnson, Arlyne; Joyner, Priscilla H; Ogg Keatts, Lucy; Khammavong, Kongsy; Nguyễn Văn, Long; Newton, Alisa; Seow, Tiffany P W; Roberton, Scott; Silithammavong, Soubanh; Singhalath, Sinpakhone; Yang, Angela; Seimon, Tracie A

    2012-12-01

    Amphibian trade is known to facilitate the geographic spread of pathogens. Here we assess the health of amphibians traded in Southeast Asia for food or as pets, focusing on Batrachochytrium dendrobatidis (Bd), ranavirus and general clinical condition. Samples were collected from 2,389 individual animals at 51 sites in Lao PDR, Cambodia, Vietnam and Singapore for Bd screening, and 74 animals in Cambodia and Vietnam for ranavirus screening. Bd was found in one frog (n = 347) in Cambodia and 13 in Singapore (n = 419). No Bd was found in Lao PDR (n = 1,126) or Vietnam (n = 497), and no ranavirus was found in Cambodia (n = 70) or Vietnam (n = 4). Mild to severe dermatological lesions were observed in all East Asian bullfrogs Hoplobatrachus rugolosus (n = 497) sampled in farms in Vietnam. Histologic lesions consistent with sepsis were found within the lesions of three frogs and bacterial sepsis in two (n = 4); one had Gram-negative bacilli and one had acid-fast organisms consistent with mycobacterium sp. These results confirm that Bd is currently rare in amphibian trade in Southeast Asia. The presence of Mycobacterium-associated disease in farmed H. rugolosus is a cause for concern, as it may have public health implications and indicates the need for improved biosecurity in amphibian farming and trade.

  13. Small pet aquarium frogs as a source of Salmonella.

    PubMed Central

    Bartlett, K H; Trust, T J; Lior, H

    1977-01-01

    Salmonellae were isolated from 21% of the samples of freshwater aquarium frogs tested and from 25% of the samples of aquarium water containing these frogs. The salmonellae were Salmonella arizonae, S. bovis-morbificans, S. hadar, S. saint-paul, S. typhimurium, and S. worthington. These isolations were made over a period of 9 months and from three different cities. This association of salmonellae with frogs may contribute to cases of human salmonellosis since other aquarium species have already been shown to contribute to such cases. PMID:879765

  14. The influence of litter quality and micro-habitat on litter decomposition and soil properties in a silvopasture system

    NASA Astrophysics Data System (ADS)

    Tripathi, G.; Deora, R.; Singh, G.

    2013-07-01

    Studies to understand litter processes and soil properties are useful for maintaining pastureland productivity as animal husbandry is the dominant occupation in the hot arid region. We aimed to quantify how micro-habitats and combinations of litters of the introduced leguminous tree Colophospermum mopane with the grasses Cenchrus ciliaris or Lasiurus sindicus influence decomposition rate and soil nutrient changes in a hot desert silvopasture system. Litter bags with tree litter alone (T), tree + C. ciliaris in 1:1 ratio (TCC) and tree + L. sindicus 1:1 ratio (TLS) litter were placed inside and outside of the C. mopane canopy and at the surface, 3-7 cm and 8-12 cm soil depths. We examined litter loss, soil fauna abundance, organic carbon (SOC), total (TN), ammonium (NH4-N) and nitrate (NO3-N) nitrogen, phosphorus (PO4-P), soil respiration (SR) and dehydrogenase activity (DHA) in soil adjacent to each litter bag. After 12 months exposure, the mean residual litter was 40.2% of the initial value and annual decomposition rate constant (k) was 0.98 (0.49-1.80). Highest (p < 0.01) litter loss was in the first four months, when faunal abundance, SR, DHA and humidity were highest but it decreased with time. These variables and k were highest under the tree canopies. The litter loss and k were highest (p < 0.01) in TLS under the tree canopy, but the reverse trend was found for litter outside the canopy. Faunal abundance, litter loss, k, nutrient release and biochemical activities were highest (p < 0.01) in the 3-7 cm soil layer. Positive correlations of litter loss and soil fauna abundance with soil nutrients, SR and DHA demonstrated the interactions of litter quality and micro-habitats together with soil fauna on increased soil fertility. These results suggest that a Colophospermum mopane and L. sindicus silvopasture system best promotes faunal abundance, litter decomposition and soil fertility. The properties of these species and the associated faunal resources may be

  15. Marine Litter, Eutrophication and Noise Assessment Tools

    NASA Astrophysics Data System (ADS)

    Palazov, Atanas; Velcheva, Maya; Milkova, Tanya; Slabakova, Violeta; Marinova, Veselka

    2017-04-01

    MARLEN - Marine Litter, Eutrophication and Noise Assessment Tools is a project under the Programme BG02.03: Increased capacity for assessing and predicting environmental status in marine and inland waters, managed by Bulgarian Ministry of environment and waters and co-financed by the Financial Mechanism of the European Economic Area (EEA FM) 2009 - 2014. Project Beneficiary is the Institute of oceanology - Bulgarian Academy of Sciences with two partners: Burgas municipality and Bulgarian Black Sea Basin Directorate. Initial assessment of ecological state of Bulgarian marine waters showed lack of data for some descriptors of MSFD. The main goal of MARLEN is to build up tools for assessment of marine environment by implementing new technologies and best practices for addressing three main areas of interest with lack of marine data in particular: a) Marine litter detection and classification in coastal areas; b) Regular near real time surface water eutrophication monitoring on large aquatory; c) Underwater noise monitoring. Developed tools are an important source of real time, near real time and delay mode marine data for Bulgarian Black Sea waters. The partnership within the project increased capacity for environmental assessments and training of personnel and enhances collaboration between scientific institutes, regional and local authorities. Project results supported implementation of MSFD in Bulgarian marine waters for the benefit of coastal population, marine industry, tourism, marine research and marine spatial planning.

  16. Soil and litter exchange of reactive trace gases

    EPA Science Inventory

    The soil and litter play an important role in the exchange of trace gases between terrestrial ecosystems and the atmosphere. - The exchange of ammonia between vegetation and the atmosphere is highly influenced by soil and litter emissions especially in managed ecosystems (grassla...

  17. Alum affects ammonia-producing microorganisms in poultry litter

    USDA-ARS?s Scientific Manuscript database

    Scientists at the USDA-ARS in Bowling Green, KY and in Fayetteville, AR are working to uncover the microbiology of ammonia production in poultry litter. Poultry litter is a valuable nutrient source for plants and microorganisms that contains high levels of protein, nitrogen, and other minerals. Howe...

  18. Litter in submarine canyons off the west coast of Portugal

    NASA Astrophysics Data System (ADS)

    Mordecai, Gideon; Tyler, Paul A.; Masson, Douglas G.; Huvenne, Veerle A. I.

    2011-12-01

    Marine litter is of global concern and is present in all the world's oceans, including deep benthic habitats where the extent of the problem is still largely unknown. Litter abundance and composition were investigated using video footage and still images from 16 Remotely Operated Vehicle (ROV) dives in Lisbon, Setúbal, Cascais and Nazaré Canyons located west of Portugal. Litter was most abundant at sites closest to the coastline and population centres, suggesting the majority of the litter was land sourced. Plastic was the dominant type of debris, followed by fishing gear. Standardised mean abundance was 1100 litter items km -2, but was as high as 6600 litter items km -2 in canyons close to Lisbon. Although all anthropogenic material may be harmful to biota, debris was also used as a habitat by some macro-invertebrates. Litter composition and abundance observed in the canyons of the Portuguese margin were comparable to those seen in other deep sea areas around the world. Accumulation of litter in the deep sea is a consequence of human activities both on land and at sea. This needs to be taken into account in future policy decisions regarding marine pollution.

  19. Radiation effects on moisture variation in ponderosa pine litter

    Treesearch

    Clive M. Countryman

    1977-01-01

    This exploratory study indicated that considerable variation in the moisture content of litter can occur within short horizontal distances. The variations ere found to be caused primarily by differences in the amount of solar radiation received by the litter and in the degree of cooling by radiation at night. Because actual fuel moisture lags behind equilibrium...

  20. Anti-Litter Curriculum Packet, Interdisciplinary, K-12.

    ERIC Educational Resources Information Center

    Tillis, Richard

    This curriculum packet consists of 20 illustrated cards with 15 activities designed to create "positive feelings" about a clean environment. Activities range from picture coloring for younger students, to lessons such as the economic and health problems litter creates for older students. Objectives include encouraging anti-litter and…

  1. Leaf Litter Inhibits Growth of an Amphibian Fungal Pathogen.

    PubMed

    Stoler, Aaron B; Berven, Keith A; Raffel, Thomas R

    2016-06-01

    Past studies have found a heterogeneous distribution of the amphibian chytrid fungal pathogen, Batrachochytrium dendrobatidis (Bd). Recent studies have accounted for some of this heterogeneity through a positive association between canopy cover and Bd abundance, which is attributed to the cooling effect of canopy cover. We questioned whether leaf litter inputs that are also associated with canopy cover might also alter Bd growth. Leaf litter inputs exhibit tremendous interspecific chemical variation, and we hypothesized that Bd growth varies with leachate chemistry. We also hypothesized that Bd uses leaf litter as a growth substrate. To test these hypotheses, we conducted laboratory trials in which we exposed cultures of Bd to leachate of 12 temperate leaf litter species at varying dilutions. Using a subset of those 12 litter species, we also exposed Bd to pre-leached litter substrate. We found that exposure to litter leachate and substrate reduced Bd spore and sporangia densities, although there was substantial variation among treatments. In particular, Bd densities were inversely correlated with concentrations of phenolic acids. We conducted a field survey of phenolic concentrations in natural wetlands which verified that the leachate concentrations in our lab study are ecologically relevant. Our study reinforces prior indications that positive associations between canopy cover and Bd abundance are likely mediated by water temperature effects, but this phenomenon might be counteracted by changes in aquatic chemistry from leaf litter inputs.

  2. Anti-Litter Curriculum Packet, Interdisciplinary, K-12.

    ERIC Educational Resources Information Center

    Tillis, Richard

    This curriculum packet consists of 20 illustrated cards with 15 activities designed to create "positive feelings" about a clean environment. Activities range from picture coloring for younger students, to lessons such as the economic and health problems litter creates for older students. Objectives include encouraging anti-litter and…

  3. Soil and litter exchange of reactive trace gases

    EPA Science Inventory

    The soil and litter play an important role in the exchange of trace gases between terrestrial ecosystems and the atmosphere. - The exchange of ammonia between vegetation and the atmosphere is highly influenced by soil and litter emissions especially in managed ecosystems (grassla...

  4. Are litter decomposition and fire linked through plant species traits?

    PubMed

    Cornelissen, Johannes H C; Grootemaat, Saskia; Verheijen, Lieneke M; Cornwell, William K; van Bodegom, Peter M; van der Wal, René; Aerts, Rien

    2017-09-11

    Contents I. II. III. IV. V. VI. VII. References SUMMARY: Biological decomposition and wildfire are connected carbon release pathways for dead plant material: slower litter decomposition leads to fuel accumulation. Are decomposition and surface fires also connected through plant community composition, via the species' traits? Our central concept involves two axes of trait variation related to decomposition and fire. The 'plant economics spectrum' (PES) links biochemistry traits to the litter decomposability of different fine organs. The 'size and shape spectrum' (SSS) includes litter particle size and shape and their consequent effect on fuel bed structure, ventilation and flammability. Our literature synthesis revealed that PES-driven decomposability is largely decoupled from predominantly SSS-driven surface litter flammability across species; this finding needs empirical testing in various environmental settings. Under certain conditions, carbon release will be dominated by decomposition, while under other conditions litter fuel will accumulate and fire may dominate carbon release. Ecosystem-level feedbacks between decomposition and fire, for example via litter amounts, litter decomposition stage, community-level biotic interactions and altered environment, will influence the trait-driven effects on decomposition and fire. Yet, our conceptual framework, explicitly comparing the effects of two plant trait spectra on litter decomposition vs fire, provides a promising new research direction for better understanding and predicting Earth surface carbon dynamics. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  5. Biosensor, ELISA, and frog embryo teratogenesis assay: Xenopus (FETAX) analysis of water associated with frog malformations in Minnesota

    NASA Astrophysics Data System (ADS)

    Garber, Eric A. E.; Erb, Judith L.; Downward, James G.; Priuska, Eric M.; Wittliff, James L.; Feng, Wenke; Magner, Joseph; Larsen, Gerald L.

    2001-03-01

    Between 1995 and 1997 over 62% of the counties in Minnesota reported the presence of malformed frogs. While most sites have recently shown a decline in malformed frog populations, one site in northeastern Minnesota with no prior history of containing malformed frogs was recently discovered to contain > 67% malformed Rana pipiens (northern leopard frogs). As part of an effort to study the presence of hormonally active agents in fresh water sources, water samples were collected from lakes in Minnesota containing malformed frogs and analyzed for the presence of hormonally active compounds using a novel evanescent field fluorometric biosensor and the frog embryo teratogenesis assay: Xenopus (FETAX) bioassay. The waveguide based biosensor developed by ThreeFold Sensors (TFS biosensor, Ann Arbor, MI) detects the presence of estrogenic compounds capable of interacting with free human ER-a and by inhibiting binding to an immobilized estrogen. The FETAX bioassay is a developmental assay, which measures teratogenicity, mortality, and inhibition of growth during the first 96 hours of organogenesis and thereby provides a universal screen for endocrine disruptors. TFS biosensor and FETAX screening of the water samples suggest a relationship between estrogenic activity, mineral supplementation, and the occurrence of malformed frogs.

  6. Nitrogen availability in composted poultry litter using natural amendments.

    PubMed

    Turan, N Gamze

    2009-02-01

    Poultry litter compost is used as fertilizer on agricultural land because of its high nutrient content. A major limitation of land application of poultry litter compost is the loss of nitrogen via NH3 volatilization. The present work was conducted to monitor nitrogen availability during composting of poultry litter with natural zeolite, expanded perlite, pumice and expanded vermiculite. Poultry litter was composted for 100 days using five in-vessel composting simulators with a volumetric ratio of natural materials:poultry litter of 1:10. It was found that natural materials significantly reduced NH3 volatilization. At the end of the process, the control treatment without any natural materials had the lowest rate of total N: 72% of the initial total N was lost from the compost made with no amendment, while 53, 42, 26 and 16% of initial total N was lost from compost containing expandable perlite, expandable vermiculite, pumice and natural zeolite, respectively.

  7. Increased decomposer diversity accelerates and potentially stabilises litter decomposition.

    PubMed

    Kitz, Florian; Steinwandter, Michael; Traugott, Michael; Seeber, Julia

    2015-04-01

    Little is known about the effect of decomposer diversity on litter decomposition in alpine areas. Especially under the premise that alpine ecosystems are very sensitive to global change and are currently undergoing extensive land-use changes, a better understanding is needed to predict how environmental change will affect litter decomposition. A mesocosm experiment was conducted to compare the effects of the most common and functionally diverse invertebrates (earthworms, millipedes and sciarid larvae) found in alpine soils on decomposition rates and to assess how decomposer diversity affects litter decomposition. Experimental and estimated (i.e. projected to field decomposer-biomass) litter mass loss was 13-33% higher in the three-species treatment. Notably, the variability in decomposition was greatly reduced when decomposer diversity was high, indicating a portfolio effect. Our results suggest that invertebrate decomposer diversity is essential for sustaining litter decomposition in alpine areas and for the stability of this service.

  8. Marine litter in bottom trawls off the Portuguese coast.

    PubMed

    Neves, Diogo; Sobral, Paula; Pereira, Tânia

    2015-10-15

    Benthic marine litter along the Portuguese coast, was recorded in 14 trips on stern trawlers covering a distance of 2117 km and an area of 56.2 km(2), average depth range 90-349 m. 2034 items of marine litter were registered, 76% were plastics and 38.6% were originated from fishing related activities. Plastic was present in all the trawls and had the highest average density of all litter categories, 50 items km(-2). The highest density of marine litter (178.9 ± 64.0 items km(-2)) was found in the proximity of the Tagus river mouth, probably related to the high population density in the Lisbon metropolitan area. This study highlights the need to raise fishermen awareness for the adoption of good environmental practices that will contribute to the reduction of marine litter.

  9. The Homing Frog: High Homing Performance in a Territorial Dendrobatid Frog Allobates femoralis (Dendrobatidae)

    PubMed Central

    Pašukonis, Andrius; Ringler, Max; Brandl, Hanja B; Mangione, Rosanna; Ringler, Eva; Hödl, Walter; Tregenza, T

    2013-01-01

    Dendrobatidae (dart-poison frogs) exhibit some of the most complex spatial behaviors among amphibians, such as territoriality and tadpole transport from terrestrial clutches to widely distributed deposition sites. In species that exhibit long-term territoriality, high homing performance after tadpole transport can be assumed, but experimental evidence is lacking, and the underlying orientation mechanisms are unknown. We conducted a field translocation experiment to test whether male Allobates femoralis, a dendrobatid frog with paternal extra-territorial tadpole transport, are capable of homing after experimental removal, as well as to quantify homing success and speed. Translocated individuals showed a very high homing success for distances up to 200 m and successfully returned from up to 400 m. We discuss the potential orientation mechanisms involved and selective forces that could have shaped this strong homing ability. PMID:25104869

  10. The Homing Frog: High Homing Performance in a Territorial Dendrobatid Frog Allobates femoralis (Dendrobatidae).

    PubMed

    Pašukonis, Andrius; Ringler, Max; Brandl, Hanja B; Mangione, Rosanna; Ringler, Eva; Hödl, Walter

    2013-09-01

    Dendrobatidae (dart-poison frogs) exhibit some of the most complex spatial behaviors among amphibians, such as territoriality and tadpole transport from terrestrial clutches to widely distributed deposition sites. In species that exhibit long-term territoriality, high homing performance after tadpole transport can be assumed, but experimental evidence is lacking, and the underlying orientation mechanisms are unknown. We conducted a field translocation experiment to test whether male Allobates femoralis, a dendrobatid frog with paternal extra-territorial tadpole transport, are capable of homing after experimental removal, as well as to quantify homing success and speed. Translocated individuals showed a very high homing success for distances up to 200 m and successfully returned from up to 400 m. We discuss the potential orientation mechanisms involved and selective forces that could have shaped this strong homing ability.

  11. [Decomposition of different plant litters in Loess Plateau of Northwest China].

    PubMed

    Li, Yun; Zhou, Jian-Bin; Dong, Yan-Jie; Xia, Zhi-Min; Chen, Zhu-Juin

    2012-12-01

    Taking the litters of species Hippophae rhamnoides, Medicago sativa, Populus simonii, Robinia pseudoacaci, Salix psammophila, and Stipa bungeana in the Loess Plateau of Northeast China as test objects, and by using mesh bags, this paper studied the dynamic changes of the litters mass, carbon, and nitrogen during decomposition after buried in the field in semiarid region. The litters buried were from one, two, or three of the plant species, and mixed thoroughly with equal proportion of masses. During decomposition, the mass loss rate, total carbon and nitrogen release rates, and total soluble carbon and nitrogen contents of different litters were higher at the early than at the later decomposition stage. After 412 d decomposition, the average mass loss rate of the litters was in the order of mixed litters of three plant species > mixed litters of two plant species > one plant species litter. By the end of this experiment, the average release rates of the litter total carbon and nitrogen ranked as one plant species litter > mixed litters of two plant species > mixed litters of three plant species, the litter soluble organic carbon content was mixed litters of two plant species > mixed litters of three plant species > one plant species litter, while the litter soluble total nitrogen content was mixed litters of three plant species > mixed litters of two plant species > one plant species litter. Correlation analysis showed that the litter mass loss rate had definite correlation with the litter soluble organic matter, especially soluble organic carbon. From the viewpoint of mass loss rate, the mixture of the litters of P. simonii, H. rhamnoide, and M. sativa was the optimum. It was suggested that in the process of returning farmland into forestland and grassland in the gully and valley region of Loess Plateau, it would be required to rationally increase plant species diversity to improve soil fertility.

  12. Correlated response in litter size components in rabbits selected for litter size variability.

    PubMed

    Argente, M J; Calle, E W; García, M L; Blasco, A

    2017-07-11

    A divergent selection experiment for the environmental variability of litter size (Ve) over seven generations was carried out in rabbits at the University Miguel Hernández of Elche. The Ve was estimated as the phenotypic variance within the female, after correcting for year-season and parity-lactation status. The aim of this study was to analyse the correlated responses to selection in litter size components. The ovulation rate (OR) and number of implanted embryos (IE) in females were measured by laparoscopy at 12 day of the second gestation. At the end of the second gestation, the total number of kits born was measured (TB). Embryonic (ES), foetal (FS) and prenatal (PS) survival were computed as IE/OR, TB/IE and TB/OR, respectively. A total of 405 laparoscopies were performed. Data were analysed using Bayesian methodology. The correlated response to selection for litter size environmental variability in terms of the litter size components was estimated as either genetic trends, estimated by computing the average estimated breeding values for each generation and each line, or the phenotypic differences between lines. The OR was similar in both lines. However, after seven generations of selection, the homogenous line showed more IE (1.09 embryos for genetic means and 1.23 embryos for phenotypic means) and higher ES than the heterogeneous one (0.07 for genetic means and 0.08 for phenotypic means). The probability of the phenotypic differences between lines being higher than zero (p) was 1.00 and .99, respectively. A higher uterine overcrowding of embryos in the homogeneous line did not penalize FS; as a result, this line continued to show a greater TB (1.01 kits for genetic means and 1.30 kits for phenotypic means, p = .99, in the seventh generation). In conclusion, a decrease in litter size variability showed a favourable effect on ES and led to a higher litter size at birth. © 2017 Blackwell Verlag GmbH.

  13. Litter mixture dominated by leaf litter of the invasive species, Flaveria bidentis, accelerates decomposition and favors nitrogen release.

    PubMed

    Li, Huiyan; Wei, Zishang; Huangfu, Chaohe; Chen, Xinwei; Yang, Dianlin

    2017-01-01

    In natural ecosystems, invasive plant litter is often mixed with that of native species, yet few studies have examined the decomposition dynamics of such mixtures, especially across different degrees of invasion. We conducted a 1-year litterbag experiment using leaf litters from the invasive species Flaveria bidentis (L.) and the dominant co-occurring native species, Setaria viridis (L.). Litters were allowed to decompose either separately or together at different ratios in a mothproof screen house. The mass loss of all litter mixtures was non-additive, and the direction and strength of effects varied with species ratio and decomposition stage. During the initial stages of decomposition, all mixtures had a neutral effect on the mass loss; however, at later stages of decomposition, mixtures containing more invasive litter had synergistic effects on mass loss. Importantly, an increase in F. bidentis litter with a lower C:N ratio in mixtures led to greater net release of N over time. These results highlight the importance of trait dissimilarity in determining the decomposition rates of litter mixtures and suggest that F. bidentis could further synchronize N release from litter as an invasion proceeds, potentially creating a positive feedback linked through invasion as the invader outcompetes the natives for nutrients. Our findings also demonstrate the importance of species composition as well as the identity of dominant species when considering how changes in plant community structure influence plant invasion.

  14. Litter production and litter elemental composition in two rehabilitated Kandelia obovata mangrove forests in Jiulongjiang Estuary, China.

    PubMed

    Ye, Y; Chen, Y P; Chen, G C

    2013-02-01

    Spatial and seasonal variations in litter production and C, N, and P concentrations were compared between the 24 and 48 year old Kandelia obovata mangrove forests in the Jiulongjiang estuary, China. The 24 yr forest had significantly higher production of total, leaf and branch litter, but lower flower and fruit litter than the 48 yr forest. Total, leaf and branch litter production were significantly positively correlated to monthly temperature and rainfall. Spatial patterns of litter production among the inner, mid and outer zones in the same forest were similar to those of tree heights. C, N and P concentrations of leaf litter showed significant seasonality but varied little among these three forest zones. C/N and N/P ratios of leaf litter were significantly lower for the 24 yr forest than those for the 48 yr forest. During the entire sampling year, total litter of the 24 and 48 yr forests contained 590.31 and 437.31 g C m(-2) yr(-1), 8.46 and 5.47 g N m(-2) yr(-1), 1.92 and 1.16 g P m(-2) yr(-1), respectively.

  15. Arsenic species in broiler (Gallus gallus domesticus) litter, soils, maize (Zea mays L.), and groundwater from litter-amended fields.

    PubMed

    D'Angelo, Elisa; Zeigler, Georgia; Beck, E Glenn; Grove, John; Sikora, Frank

    2012-11-01

    Manure and bedding material (litter) generated by the broiler industry (Gallus gallus domesticus) often contain high levels of arsenic (As) when organoarsenical roxarsone and p-arsanilic acid are included in feed to combat disease and improve weight gain of the birds. This study was conducted to determine As levels and species in litter from three major broiler producing companies, and As levels in soils, corn tissue (Zea mays L.), and groundwater in fields where litter was applied. Total As in litter from the three different integrators ranged between <1 and 44 mg kg(-1). Between 15 and 20% of total As in litter consisted of mostly of arsenate, with smaller amounts of roxarsone and several transformation products that were extractable with phosphate buffer. Soils amended with litter had higher levels of bioavailable As (extractable with Mehlich 3 solution and taken up by corn leaves). Arsenic concentrations in plant tissue and groundwater, however, were below the World Health Organization thresholds, which was attributed to strong sorption/precipitation of arsenate in Fe- and Al-rich soils. Ecological impacts of amending soils with As-laden litter depend on the As species in the litter, and chemical and physical properties of soil that strongly affect As mobility and bioavailability in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Two new Phrynobatrachus species (Amphibia: Anura: Phrynobatrachidae) from the Republic of the Congo.

    PubMed

    Rödel, Mark-Oliver; Burger, Marius; Zassi-Boulou, Ange Ghislain; Emmrich, Mike; Penner, Johannes; Barej, Michael F

    2015-10-14

    We describe two new species of puddle frogs, genus Phrynobatrachus, from the south-western Republic of the Congo. One of them, P. horsti sp. nov., occurs also in neighbouring Gabon and is morphologically most similar to the Cameroonian P. ruthbeateae. It differs from the latter species by smaller males with longer thighs and shanks. The new species comprises various colour morphs but always has less conspicuous black borders between flanks and belly than P. ruthbeateae. The distinct and large black axillary blotch of P. ruthbeateae is either much smaller in P. horsti sp. nov., or broken into numerous irregularly shaped smaller dots. Similarly, a black transversal line at the anterior ventral border of thighs and the black face mask is less distinct and irregularly delimitated in P. horsti sp. nov. when compared to P. ruthbeateae. The mean genetic difference in the sampled region of the 16S rRNA gene between P. horsti sp. nov. and 40 other western African congeners range from 3.66-18.10%. The second new species, P. mayokoensis sp. nov., differs from all other known congeners by the combination of a compact and warty body, the absence of a spiny eyelid tubercle and pedal webbing, a conspicuous black triangle on throat and anterior part of the belly, and a distinct large red blotch on the anterior-proximal surface of the thighs. It exhibited a mean genetic difference in the 16S rRNA to 40 other western African congeners ranging from 1.34-16.98%. The genetically most similar sequence stems from a GenBank entry of a Gabonese frog, determined as P. ogoensis. A comparison of the new species with P. ogoensis syntypes confirmed their specific distinctiveness, most convincingly underlined by the absence of pedal webbing in the new species and the pronounced pedal webbing in P. ogoensis. The GenBank entry thus most likely is based on a misidentification and P. mayokoensis sp. nov. may also occur in neighbouring Gabon. The discovery of the two new frog species is further

  17. Frog: The fast & realistic OpenGL event displayer

    NASA Astrophysics Data System (ADS)

    Quertenmont, Loïc

    2010-04-01

    FROG [1] [2] is a generic framework dedicated to visualisation of events in high energy physics experiment. It is suitable to any particular physics experiment or detector design. The code is light (< 3 MB) and fast (browsing time ~ 20 events per second for a large High Energy Physics experiment) and can run on various operating systems, as its object-oriented structure (C++) relies on the cross-platform OpenGL[3] and Glut [4] libraries. Moreover, Frog does not require installation of heavy third party libraries for the visualisation. This documents describes the features and principles of Frog version 1.106, its working scheme and numerous functionalities such as: 3D and 2D visualisation, graphical user interface, mouse interface, configuration files, production of pictures of various format, integration of personal objects, etc. Finally the application of FROG for physic experiment/environement, such as Gastof, CMS, ILD, Delphes will be presented for illustration.

  18. Modeling synchronized calling behavior of Japanese tree frogs

    NASA Astrophysics Data System (ADS)

    Aihara, Ikkyu

    2009-07-01

    We experimentally observed synchronized calling behavior of male Japanese tree frogs Hyla japonica; namely, while isolated single frogs called nearly periodically, a pair of interacting frogs called synchronously almost in antiphase or inphase. In this study, we propose two types of phase-oscillator models on different degrees of approximations, which can quantitatively explain the phase and frequency properties in the experiment. Moreover, it should be noted that, although the second model is obtained by fitting to the experimental data of the two synchronized states, the model can also explain the transitory dynamics in the interactive calling behavior, namely, the shift from a transient inphase state to a stable antiphase state. We also discuss the biological relevance of the estimated parameter values to calling behavior of Japanese tree frogs and the possible biological meanings of the synchronized calling behavior.

  19. Games With a Purpose: Frog and the Lily Pads

    ERIC Educational Resources Information Center

    Sawicki, Timothy

    2005-01-01

    This article describes a game involving poly spots, frog bean bags, and a basket that can be used to assess locomotor activities, e.g., hopping and throwing, while also developing teamwork strategies and mathematical abilities.

  20. Games With a Purpose: Frog and the Lily Pads

    ERIC Educational Resources Information Center

    Sawicki, Timothy

    2005-01-01

    This article describes a game involving poly spots, frog bean bags, and a basket that can be used to assess locomotor activities, e.g., hopping and throwing, while also developing teamwork strategies and mathematical abilities.

  1. Distinct bacterial communities dominate tropical and temperate zone leaf litter.

    PubMed

    Kim, Mincheol; Kim, Woo-Sung; Tripathi, Binu M; Adams, Jonathan

    2014-05-01

    Little is known of the bacterial community of tropical rainforest leaf litter and how it might differ from temperate forest leaf litter and from the soils underneath. We sampled leaf litter in a similarly advanced stage of decay, and for comparison, we also sampled the surface layer of soil, at three tropical forest sites in Malaysia and four temperate forest sites in South Korea. Illumina sequencing targeting partial bacterial 16S ribosomal ribonucleic acid (rRNA) gene revealed that the bacterial community composition of both temperate and tropical litter is quite distinct from the soils underneath. Litter in both temperate and tropical forest was dominated by Proteobacteria and Actinobacteria, while soil is dominated by Acidobacteria and, to a lesser extent, Proteobacteria. However, bacterial communities of temperate and tropical litter clustered separately from one another on an ordination. The soil bacterial community structures were also distinctive to each climatic zone, suggesting that there must be a climate-specific biogeographical pattern in bacterial community composition. The differences were also found in the level of diversity. The temperate litter has a higher operational taxonomic unit (OTU) diversity than the tropical litter, paralleling the trend in soil diversity. Overall, it is striking that the difference in community composition between the leaf litter and the soil a few centimeters underneath is about the same as that between leaf litter in tropical and temperate climates, thousands of kilometers apart. However, one substantial difference was that the leaf litter of two tropical forest sites, Meranti and Forest Research Institute Malaysia (FRIM), was overwhelmingly dominated by the single genus Burkholderia, at 37 and 23 % of reads, respectively. The 454 sequencing result showed that most Burkholderia species in tropical leaf litter belong to nonpathogenic "plant beneficial" lineages. The differences from the temperate zone in the bacterial

  2. Mixing effects on litter decomposition rates in a young tree diversity experiment

    NASA Astrophysics Data System (ADS)

    Setiawan, Nuri Nurlaila; Vanhellemont, Margot; De Schrijver, An; Schelfhout, Stephanie; Baeten, Lander; Verheyen, Kris

    2016-01-01

    Litter decomposition is an essential process for biogeochemical cycling and for the formation of new soil organic matter. Mixing litter from different tree species has been reported to increase litter decomposition rates through synergistic effects. We assessed the decomposition rates of leaf litter from five tree species in a recently established tree diversity experiment on a post-agriculture site in Belgium. We used 20 different leaf litter compositions with diversity levels ranging from 1 up to 4 species. Litter mass loss in litterbags was assessed 10, 20, 25, 35, and 60 weeks after installation in the field. We found that litter decomposition rates were higher for high-quality litters, i.e., with high nitrogen content and low lignin content. The decomposition rates of mixed litter were more affected by the identity of the litter species within the mixture than by the diversity of the litter per se, but the variability in litter decomposition rates decreased as the litter diversity increased. Among the 15 different mixed litter compositions in our study, only three litter combinations showed synergistic effects. Our study suggests that admixing tree species with high-quality litter in post-agricultural plantations helps in increasing the mixture's early-stage litter decomposition rate.

  3. Frog tongue surface microstructures: functional and evolutionary patterns

    PubMed Central

    Gorb, Stanislav N

    2016-01-01

    Summary Frogs (Lissamphibia: Anura) use adhesive tongues to capture fast moving, elusive prey. For this, the tongues are moved quickly and adhere instantaneously to various prey surfaces. Recently, the functional morphology of frog tongues was discussed in context of their adhesive performance. It was suggested that the interaction between the tongue surface and the mucus coating is important for generating strong pull-off forces. However, despite the general notions about its importance for a successful contact with the prey, little is known about the surface structure of frog tongues. Previous studies focused almost exclusively on species within the Ranidae and Bufonidae, neglecting the wide diversity of frogs. Here we examined the tongue surface in nine different frog species, comprising eight different taxa, i.e., the Alytidae, Bombinatoridae, Megophryidae, Hylidae, Ceratophryidae, Ranidae, Bufonidae, and Dendrobatidae. In all species examined herein, we found fungiform and filiform papillae on the tongue surface. Further, we observed a high degree of variation among tongues in different frogs. These differences can be seen in the size and shape of the papillae, in the fine-structures on the papillae, as well as in the three-dimensional organization of subsurface tissues. Notably, the fine-structures on the filiform papillae in frogs comprise hair-like protrusions (Megophryidae and Ranidae), microridges (Bufonidae and Dendrobatidae), or can be irregularly shaped or absent as observed in the remaining taxa examined herein. Some of this variation might be related to different degrees of adhesive performance and may point to differences in the spectra of prey items between frog taxa. PMID:27547606

  4. Litter dynamics in two Sierran mixed conifer forests. II. Nutrient release in decomposing leaf litter

    USGS Publications Warehouse

    Stohlgren, Thomas J.

    1988-01-01

    The factors influencing leaf litter decomposition and nutrient release patterns were investigated for 3.6 years in two mixed conifer forests in the southern Sierra Nevada of California. The giant sequoia–fir forest was dominated by giant sequoia (Sequoiadendrongiganteum (Lindl.) Buchh.), white fir (Abiesconcolor Lindl. & Gord.), and sugar pine (Pinuslambertiana Dougl.). The fir–pine forest was dominated by white fir, sugar pine, and incense cedar (Calocedrusdecurrens (Torr.) Florin). Initial concentrations of nutrients and percent lignin, cellulose, and acid detergent fiber vary considerably in freshly abscised leaf litter of the studied species. Giant sequoia had the highest concentration of lignin (20.3%) and the lowest concentration of nitrogen (0.52%), while incense cedar had the lowest concentration of lignin (9.6%) and second lowest concentration of nitrogen (0.63%). Long-term (3.6 years) foliage decomposition rates were best correlated with initial lignin/N (r2 = 0.94, p r2 = 0.92, p r2 = 0.80, p < 0.05). Patterns of nutrient release were highly variable. Giant sequoia immobilized N and P, incense cedar immobilized N and to a lesser extent P, while sugar pine immobilized Ca. Strong linear or negative exponential relationships existed between initial concentrations of N, P, K, and Ca and percent original mass remaining of those nutrients after 3.6 years. This suggests efficient retention of these nutrients in the litter layer of these ecosystems. Nitrogen concentrations steadily increase in decomposing leaf litter, effectively reducing the C/N ratios from an initial range of 68–96 to 27–45 after 3.6 years.

  5. Climate, Litter Chemistry, and Nitrogen Controls on Litter Decomposition and Organic Matter Stabilization

    NASA Astrophysics Data System (ADS)

    DelGrosso, S.; Parton, W. J.; Adair, C.

    2012-12-01

    Climate interacts with N availability and other factors to control organic matter decomposition rates and carbon cycling. We analyzed data from the LIDET (Long-Term Inter-site Decomposition Experiment Team) experiment to investigate the controls on litter decomposition rates and organic matter stabilization. Bags containing vegetative litter from different woody and herbaceous species were placed in 28 sites representing a wide array of biomes. Samples were collected approximately ten times, once per year for all sites except tropical sites, which were sampled every 3-6 months. Each sample was analyzed for total N, ash, lignin, and cellulose using near infrared reflectance spectroscopy. To account for water and temperature impacts on decomposition, we calculated a Climate Decomposition Index (CDI) for each site based on long term weather data. We then performed step-wise regression analyses to test how well CDI and litter chemistry were correlated with the amount of biomass remaining in litter bags after 1, 5, and 10 years. CDI was the primary control, accounting for 74, 48, and 58% of variability in biomass remaining at 1, 5, and 10 years, respectively. In addition to CDI, The C/N ratio of labile organic matter and lignin content significantly impacted biomass remaining at 1 and 5 years, while lignin and cellulose content were significant for biomass remaining at 10 years. Increased C/N ratio was associated with slower initial decomposition rate. Lignin content was positively, and cellulose negatively, correlated with long term organic matter stabilization. If CDI and lignin content were similar, then C/N did not influence long term stabilization. If N was not limiting, cellulose decomposed quickly.

  6. Salinity tolerance of eggs of Buergeria japonica (Amphibia, Anura) inhabiting coastal areas.

    PubMed

    Haramura, Takashi

    2007-08-01

    Buergeria japonica is one of a few frogs that breed in coastal areas. To understand why this species can breed in coastal areas, I tested the salinity tolerance of eggs of B. japonica collected from a coastal area of Okinawa Island, Japan. All eggs hatched within four days after oviposition. At 0%. salinity (control), over 94% of eggs hatched normally, and even at 1 per thousand salinity over 85% of eggs hatched. Survival rate of eggs was low at 2, 3, and 4 per thousand, and no eggs hatched at 5 per thousand salinity. These results indicate that low salinity, close to pure water, is necessary for successful egg development, even for populations of B. japonica that breed in coastal areas. Future studies are necessary to examine whether females of B. japonica breeding in coastal areas select appropriate oviposition sites where the environmental salinity level is sufficiently low for eggs.

  7. Changes in litter quality induced by nutrient addition alter litter decomposition in an alpine meadow on the Qinghai-Tibet Plateau

    PubMed Central

    Zhu, Wenyan; Wang, Jinzhou; Zhang, Zhenhua; Ren, Fei; Chen, Litong; He, Jin-Sheng

    2016-01-01

    The effects of nitrogen (N) and phosphorus (P) addition on litter decomposition are poorly understood in Tibetan alpine meadows. Leaf litter was collected from plots within a factorial N × P addition experiment and allowed to decompose over 708 days in an unfertilized plot to determine the effects of N and/or P addition on litter decomposition. Results showed that nutrient addition significantly affected initial P and P-related biochemical properties of litter from all four species. However, the responses of litter N and N-related biochemical properties to nutrient addition were quite species-specific. Litter C decomposition and N release were species-specific. However, N and P addition significantly affected litter P release. Ratios of Hemicellulose + Cellulose to N and P were significantly related to litter C decomposition; C:N ratio was a determinant of litter N release; and C:P and (Hemicellulose + Cellulose):P controlled litter P release. Overall, litter C decomposition was controlled by litter quality of different plant species, and strongly affected by P addition. Increasing N availability is likely to affect litter C decomposition more indirectly by shifting plant species composition than directly by improving litter quality, and may accelerate N and P cycles, but shift the ecosystem to P limitation. PMID:27694948

  8. Changes in litter quality induced by nutrient addition alter litter decomposition in an alpine meadow on the Qinghai-Tibet Plateau.

    PubMed

    Zhu, Wenyan; Wang, Jinzhou; Zhang, Zhenhua; Ren, Fei; Chen, Litong; He, Jin-Sheng

    2016-10-03

    The effects of nitrogen (N) and phosphorus (P) addition on litter decomposition are poorly understood in Tibetan alpine meadows. Leaf litter was collected from plots within a factorial N × P addition experiment and allowed to decompose over 708 days in an unfertilized plot to determine the effects of N and/or P addition on litter decomposition. Results showed that nutrient addition significantly affected initial P and P-related biochemical properties of litter from all four species. However, the responses of litter N and N-related biochemical properties to nutrient addition were quite species-specific. Litter C decomposition and N release were species-specific. However, N and P addition significantly affected litter P release. Ratios of Hemicellulose + Cellulose to N and P were significantly related to litter C decomposition; C:N ratio was a determinant of litter N release; and C:P and (Hemicellulose + Cellulose):P controlled litter P release. Overall, litter C decomposition was controlled by litter quality of different plant species, and strongly affected by P addition. Increasing N availability is likely to affect litter C decomposition more indirectly by shifting plant species composition than directly by improving litter quality, and may accelerate N and P cycles, but shift the ecosystem to P limitation.

  9. Graded Activation in Frog Muscle Fibers

    PubMed Central

    Costantin, L. L.; Taylor, S. R.

    1973-01-01

    The membrane potential of frog single muscle fibers in solutions containing tetrodotoxin was controlled with a two-electrode voltage clamp. Local contractions elicited by 100-ms square steps of depolarization were observed microscopically and recorded on cinefilm. The absence of myofibrillar folding with shortening to striation spacings below 1.95 µm served as a criterion for activation of the entire fiber cross section. With depolarizing steps of increasing magnitude, shortening occurred first in the most superficial myofibrils and spread inward to involve axial myofibrils as the depolarization was increased. In contractions in which the entire fiber cross section shortened actively, both the extent of shortening and the velocity of shortening at a given striation spacing could be graded by varying the magnitude of the depolarization step. The results provide evidence that the degree of activation of individual myofibrils can be graded with membrane depolarization. PMID:4540418

  10. Ecology: the proximate cause of frog declines?

    PubMed

    Di Rosa, Ines; Simoncelli, Francesca; Fagotti, Anna; Pascolini, Rita

    2007-05-31

    Pounds et al. argue that global warming contributes to amphibian declines by encouraging outbreaks of the chytrid fungus Batrachochytrium dendrobatidis. Although our findings agree with the climate-linked epidemic hypothesis, this pathogen is probably not the only proximate factor in such cases: in the Trasimeno Lake area of Umbria in central Italy, for example, the water frog Rana lessonae first declined in the late 1990s, yet chytridiomycosis was not observed until 2003 (refs 5, 6). Here we show that the chytrid was common there throughout 1999-2002, in a previously unknown form that did not cause disease. We therefore think that the focus by Pounds et al. on a single pathogen is hard to justify because the host-parasite ecology is at present so poorly understood.

  11. Limb malformations and abnormal sex hormone concentrations in frogs.

    PubMed Central

    Sower, S A; Reed, K L; Babbitt, K J

    2000-01-01

    Declines in amphibian populations, and amphibians with gross malformations, have prompted concern regarding the biological status of many anuran species. A survey of bullfrogs, Rana catesbeiana, and green frogs, Rana clamitans, conducted in central and southern New Hampshire showed malformed frogs at 81% of the sites sampled (13 of 16 sites). Brain gonadotropin-releasing hormone (GnRH) and the synthesis of androgens and estradiol, hormones essential to reproductive processes, were measured from limb-malformed and normal (no limb malformation) frogs. Normal frogs had significantly higher concentrations (nearly 3-fold) of in vitro produced androgens and of brain GnRH than malformed frogs. Because most malformations are thought to occur during development, we propose that environmental factors or endocrine-disrupting chemicals that may cause developmental abnormalities also act during early development to ultimately cause abnormally reduced GnRH and androgen production in adult frogs. The consequences of reduced GnRH and androgens on anuran reproductive behavior and population dynamics are unknown but certainly may be profound and warrant further research. PMID:11102301

  12. Frog tongue acts as muscle-powered adhesive tape.

    PubMed

    Kleinteich, Thomas; Gorb, Stanislav N

    2015-09-01

    Frogs are well known to capture fast-moving prey by flicking their sticky tongues out of the mouth. This tongue projection behaviour happens extremely fast which makes frog tongues a biological high-speed adhesive system. The processes at the interface between tongue and prey, and thus the mechanism of adhesion, however, are completely unknown. Here, we captured the contact mechanics of frog tongues by filming tongue adhesion at 2000 frames per second through an illuminated glass. We found that the tongue rolls over the target during attachment. However, during the pulling phase, the tongue retractor muscle acts perpendicular to the target surface and thus prevents peeling during tongue retraction. When the tongue detaches, mucus fibrils form between the tongue and the target. Fibrils commonly occur in pressure-sensitive adhesives, and thus frog tongues might be a biological analogue to these engineered materials. The fibrils in frog tongues are related to the presence of microscopic papillae on the surface. Together with a layer of nanoscale fibres underneath the tongue epithelium, these surface papillae will make the tongue adaptable to asperities. For the first time, to the best of our knowledge, we are able to integrate anatomy and function to explain the processes during adhesion in frog tongues.

  13. Pure Ultrasonic Communication in an Endemic Bornean Frog

    PubMed Central

    Arch, Victoria S.; Grafe, T. Ulmar; Gridi-Papp, Marcos; Narins, Peter M.

    2009-01-01

    Huia cavitympanum, an endemic Bornean frog, is the first amphibian species known to emit exclusively ultrasonic (i.e., >20 kHz) vocal signals. To test the hypothesis that these frogs use purely ultrasonic vocalizations for intraspecific communication, we performed playback experiments with male frogs in their natural calling sites. We found that the frogs respond with increased calling to broadcasts of conspecific calls containing only ultrasound. The field study was complemented by electrophysiological recordings from the auditory midbrain and by laser Doppler vibrometer measurements of the tympanic membrane's response to acoustic stimulation. These measurements revealed that the frog's auditory system is broadly tuned over high frequencies, with peak sensitivity occurring within the ultrasonic frequency range. Our results demonstrate that H. cavitympanum is the first non-mammalian vertebrate described to communicate with purely ultrasonic acoustic signals. These data suggest that further examination of the similarities and differences in the high-frequency/ultrasonic communication systems of H. cavitympanum and Odorrana tormota, an unrelated frog species that produces and detects ultrasound but does not emit exclusively ultrasonic calls, will afford new insights into the mechanisms underlying vertebrate high-frequency communication. PMID:19401782

  14. Frog tongue acts as muscle-powered adhesive tape

    PubMed Central

    Kleinteich, Thomas; Gorb, Stanislav N.

    2015-01-01

    Frogs are well known to capture fast-moving prey by flicking their sticky tongues out of the mouth. This tongue projection behaviour happens extremely fast which makes frog tongues a biological high-speed adhesive system. The processes at the interface between tongue and prey, and thus the mechanism of adhesion, however, are completely unknown. Here, we captured the contact mechanics of frog tongues by filming tongue adhesion at 2000 frames per second through an illuminated glass. We found that the tongue rolls over the target during attachment. However, during the pulling phase, the tongue retractor muscle acts perpendicular to the target surface and thus prevents peeling during tongue retraction. When the tongue detaches, mucus fibrils form between the tongue and the target. Fibrils commonly occur in pressure-sensitive adhesives, and thus frog tongues might be a biological analogue to these engineered materials. The fibrils in frog tongues are related to the presence of microscopic papillae on the surface. Together with a layer of nanoscale fibres underneath the tongue epithelium, these surface papillae will make the tongue adaptable to asperities. For the first time, to the best of our knowledge, we are able to integrate anatomy and function to explain the processes during adhesion in frog tongues. PMID:26473054

  15. Cutaneous acariasis in the African clawed frog (Xenopus laevis).

    PubMed

    Ford, Timothy R; Dillehay, Dirck L; Mook, Deborah M

    2004-12-01

    Increased mortality was observed in a single colony of 50 Xenopus laevis. The frogs were used as oocyte donors in developmental biology studies. Necropsy findings included dermal erythema and petechiation consistent with red leg syndrome; dermal ulcerations and white, filamentous growths on the skin were consistent with Saprolegnia sp. Microscopic evaluation of the skin and fungus revealed an astigmatid mite similar to those of the genus Rhizoglyphus. The mite was also found in the water and the biological filter of the tanks housing the frogs. This mite is considered not to be a parasite of X. laevis; instead, it feeds off moss, fungi, and detritus. Subsequent evaluation of the sphagnum moss used for shipping the frogs from the supplier revealed the same mite in the moss. Our hypothesis is that the mite was introduced into the tank with the shipment of new frogs in sphagnum moss. The mites lived within the biological filter, and were only found after the growth of Saprolegnia sp. attracted the mites to the frogs. Laboratory animal care and veterinary personnel should consider non-pathogenic species of mites in the differential diagnosis of acariasis in Xenopus frogs.

  16. Distribution, structure and projections of the frog intracardiac neurons.

    PubMed

    Batulevicius, Darius; Skripkiene, Gertruda; Batuleviciene, Vaida; Skripka, Valdas; Dabuzinskiene, Anita; Pauza, Dainius H

    2012-05-21

    Histochemistry for acetylcholinesterase was used to determine the distribution of intracardiac neurons in the frog Rana temporaria. Seventy-nine intracardiac neurons from 13 frogs were labelled iontophoretically by the intracellular markers Alexa Fluor 568 and Lucifer Yellow CH to determine their structure and projections. Total neuronal number per frog heart was (Mean ± SE) 1374 ± 56. Largest collections of neurons were found in the interatrial septum (46%), atrioventricular junction (25%) and venal sinus (12%). Among the intracellularly labelled neurons, we found the cells of unipolar (71%), multipolar (20%) and bipolar (9%) types. Multiple processes originated from the neuron soma, hillock and proximal axon. These processes projected onto adjacent neuron somata and cardiac muscle fibers within the interatrial septum. Average total length of the processes from proximal axon was 348 ± 50 μm. Average total length of processes from soma and hillock was less, 118 ± 27 μm and 109 ± 24 μm, respectively. The somata of 59% of neurons had bubble- or flake-shaped extensions. Most neurons from the major nerves in the interatrial septum sent their axons towards the ventricle. In contrast, most neurons from the ventral part of the interatrial septum sent their axons towards the atria. Our findings contradict to a view that the frog intracardiac ganglia contain only non-dendritic neurons of the unipolar type. We conclude that the frog intracardiac neurons are structurally complex and diverse. This diversity may account for the complicated integrative functions of the frog intrinsic cardiac ganglia.

  17. Analysis of litter size and average litter weight in pigs using a recursive model.

    PubMed

    Varona, Luis; Sorensen, Daniel; Thompson, Robin

    2007-11-01

    An analysis of litter size and average piglet weight at birth in Landrace and Yorkshire using a standard two-trait mixed model (SMM) and a recursive mixed model (RMM) is presented. The RMM establishes a one-way link from litter size to average piglet weight. It is shown that there is a one-to-one correspondence between the parameters of SMM and RMM and that they generate equivalent likelihoods. As parameterized in this work, the RMM tests for the presence of a recursive relationship between additive genetic values, permanent environmental effects, and specific environmental effects of litter size, on average piglet weight. The equivalent standard mixed model tests whether or not the covariance matrices of the random effects have a diagonal structure. In Landrace, posterior predictive model checking supports a model without any form of recursion or, alternatively, a SMM with diagonal covariance matrices of the three random effects. In Yorkshire, the same criterion favors a model with recursion at the level of specific environmental effects only, or, in terms of the SMM, the association between traits is shown to be exclusively due to an environmental (negative) correlation. It is argued that the choice between a SMM or a RMM should be guided by the availability of software, by ease of interpretation, or by the need to test a particular theory or hypothesis that may best be formulated under one parameterization and not the other.

  18. Effect of mountain climatic elevation gradient and litter origin on decomposition processes: long-term experiment with litter-bags

    NASA Astrophysics Data System (ADS)

    Klimek, Beata; Niklińska, Maria; Chodak, Marcin

    2013-04-01

    Temperature is one of the most important factors affecting soil organic matter decomposition. Mountain areas with vertical gradients of temperature and precipitation provide an opportunity to observe climate changes similar to those observed at various latitudes and may serve as an approximation for climatic changes. The aim of the study was to compare the effects of climatic conditions and initial properties of litter on decomposition processes and thermal sensitivity of forest litter. The litter was collected at three altitudes (600, 900, 1200 m a.s.l.) in the Beskidy Mts (southern Poland), put into litter-bags and exposed in the field since autumn 2011. The litter collected at single altitude was exposed at the altitude it was taken and also at the two other altitudes. The litter-bags were laid out on five mountains, treated as replicates. Starting on April 2012, single sets of litter-bags were collected every five weeks. The laboratory measurements included determination of dry mass loss and chemical composition (Corg, Nt, St, Mg, Ca, Na, K, Cu, Zn) of the litter. In the additional litter-bag sets, taken in spring and autumn 2012, microbial properties were measured. To determine the effect of litter properties and climatic conditions of elevation sites on decomposing litter thermal sensitivity the respiration rate of litter was measured at 5°C, 15°C and 25°C and calculated as Q10 L and Q10 H (ratios of respiration rate between 5° and 15°C and between 15°C and 25°C, respectively). The functional diversity of soil microbes was measured with Biolog® ECO plates, structural diversity with phospholipid fatty acids (PLFA). Litter mass lost during first year of incubation was characterized by high variability and mean mass lost ranged up to a 30% of initial mass. After autumn sampling we showed, that mean respiration rate of litter (dry mass) from the 600m a.s.l site exposed on 600m a.s.l. was the highest at each tested temperature. In turn, the lowest mean

  19. Frog Foam Nest Protein Diversity and Synthesis.

    PubMed

    Hissa, Denise Cavalcante; Bezerra, Walderly Melgaço; Freitas, Cléverson Diniz Teixeira De; Ramos, Márcio Viana; Lopes, José Luiz De Souza; Beltramini, Leila Maria; Roberto, Igor Joventino; Cascon, Paulo; Melo, Vânia Maria Maciel

    2016-08-01

    Some amphibian species have developed a breeding strategy in which they deposit their eggs in stable foam nests to protect their eggs and larvae. The frog foam nests are rich in proteins (ranaspumin), especially surfactant proteins, involved in the production of the foam nest. Despite the ecological importance of the foam nests for evolution and species conservation, the biochemical composition, the long-term stability and even the origin of the components are still not completely understood. Recently we showed that Lv-RSN-1, a 23.5-kDa surfactant protein isolated from the nest of the frog Leptodacylus vastus, presents a structural conformation distinct from any protein structures yet reported. So, in the current study we aimed to reveal the protein composition of the foam nest of L. vastus and further characterize the Lv-RSN-1. Proteomic analysis showed the foam nest contains more than 100 of proteins, and that Lv-RSN-1 comprises 45% of the total proteins, suggesting a key role in the nest construction and stability. We demonstrated by Western blotting that Lv-RSN-1 is mainly produced only by the female in the pars convoluta dilata, which highlights the importance of the female preservation for conservation of species that depend on the production of foam nests in the early stages of development. Overall, our results showed the foam nest of L. vastus is composed of a great diversity of proteins and that besides Lv-RSN-1, the main protein in the foam, other proteins must have a coadjuvant role in building and stability of the nest.

  20. Leaf litter input mediates tadpole performance across forest canopy treatments.

    PubMed

    Williams, Bethany K; Rittenhouse, Tracy A G; Semlitsch, Raymond D

    2008-03-01

    Understanding the mechanisms limiting the distributions of organisms is necessary for predicting changes in community composition along habitat gradients. In many areas of the USA, land originally cleared for agriculture has been undergoing a process of reforestation, creating a gradient of canopy cover. For small temporary wetlands, this gradient can alter abiotic conditions and influence the resource base of wetland food webs by affecting litter inputs. As distributions of amphibians and many other temporary wetland taxa correlate with canopy cover, we experimentally manipulated shade levels and litter types in pond mesocosms to explore mechanisms limiting species performance in wetlands with canopy cover. Most differences between ponds were mediated by litter type rather than direct effects of shading. Although all three amphibian species tested are open-canopy specialists, spring peepers were the only species to show decreased survival in shaded ponds. Pond litter type generally had strong effects on growth and development rates, with tadpoles of two species in grass litter ponds growing to twice the size of, and metamorphosing 7 days earlier than, those in leaf litter ponds. Contrary to our initial hypothesis, shade level and litter type showed very few significant interactions. Our results indicate that the effects of shading cannot be considered in isolation of vegetation changes in pond basins when evaluating the effects of forest succession on temporary pond communities.

  1. Frogs on the beach: Ecology of California Red-legged Frogs (Rana draytonii) in coastal dune drainages

    USGS Publications Warehouse

    Halstead, Brian J.; Kleeman, Patrick M.

    2017-01-01

    California Red-legged Frogs (Rana draytonii) are typically regarded as inhabitants of permanent ponds, marshes, and slow-moving streams, but their ecology in other habitats, such as drainages among coastal dunes, remains obscure. Because coastal dune ecosystems have been degraded by development, off-highway vehicle use, stabilization, and invasive species, these unique ecosystems are the focus of restoration efforts. To better understand the ecology of California Red-legged Frogs in coastal dune ecosystems and to avoid and minimize potential negative effects of dune restoration activities on these rare frogs, we studied their spatial ecology, habitat selection, and survival in coastal dune drainages at Point Reyes National Seashore, California, USA. All 22 radio-marked frogs remained in their home drainages throughout the spring and summer of 2015 and, with some notable exceptions, most remained close to water. Local convex hull home ranges of four out of five California Red-legged Frogs with > 20 observations in dunes were < 1,600 m2 . At the population level, frogs were 1.7 (95% credible interval, 1.2‒4.4) times more likely to select sites 1 m closer to water, and were 83 (2.0‒17,000) times more likely to select sites with 10% greater percentage cover of logs that served as refuges from environmental extremes and predators. On average, California Red-legged Frogs avoided the invasive plants Iceplant (Carpobrotus edulis) and European Beachgrass (Ammophila arenaria). Frogs were 0.68 (0.32‒0.89) and 0.55 (0.24‒0.75) times as likely to select areas that had 10% greater cover of these plants, respectively. Assuming constant risk of mortality, California Redlegged Frogs had an annual survival rate of 0.70 (0.27‒0.96) in coastal dune drainages. Our results indicate that coastal dune drainages provide a locally important habitat for California Red-legged Frogs. Restoration practices that maintain wetted drainages with logjams are likely to benefit California

  2. Tree litter and forest understorey vegetation: a conceptual framework to understand the effects of tree litter on a perennial geophyte, Anemone nemorosa.

    PubMed

    Baltzinger, Marie; Archaux, Frédéric; Dumas, Yann

    2012-05-01

    Litter is a key factor in structuring plant populations, through positive or negative interactions. The litter layer forms a mechanical barrier that is often strongly selective against individuals lacking hypocotyle plasticity. Litter composition also interacts with plant growth by providing beneficial nutrients or, inversely, by allowing harmful allelopathic leaching. As conspicuous litter fall accumulation is often observed under deciduous forests, interactions between tree litter and understorey plant populations are worthy of study. In a 1-year ex-situ experiment, the effects of tree litter on the growth of Anemone nemorosa, a small perennial forest geophyte, were investigated. Three 'litter quantity' treatments were defined, representative of forest floor litter (199, 356·5 and 514 g m(-2)), which were crossed with five 'litter composition' treatments (Quercus petraea, Fagus sylvatica, Carpinus betulus, Q. petraea + F. sylvatica and Q. petraea + C. betulus), plus a no-litter control. Path analysis was then used to investigate the pathways linking litter characteristics and components of adult plant growth. As expected, the heavier the litter, the longer the petiole; rhizome growth, however, was not depreciated by the litter-induced petiole lengthening. Both rhizome mass increment and number of initiated buds marginally increased with the amount of litter. Rhizome mass increment was in fact determined primarily by leaf area and leaf life span, neither of which was unequivocally correlated with any litter characteristics. However, the presence of litter significantly increased leafing success: following a late frost event, control rhizomes growing in the absence of litter experienced higher leaf mortality before leaf unfolding. The study questions the role of litter as a physical or chemical barrier to ground vegetation; to better understand this role, there is a need for ex-situ, longer-term experiments coupled with in-situ observations in the forest.

  3. Long-term effects of poultry litter, alum-treated litter, and ammonium nitrate on aluminum availability in soils.

    PubMed

    Moore, P A; Edwards, D R

    2005-01-01

    Research has shown that alum [Al(2)(SO(4))(3).14H(2)O] applications to poultry litter can greatly reduce phosphorus (P) runoff, as well as decrease ammonia (NH(3)) volatilization. However, the long-term effects of fertilizing with alum-treated litter are unknown. The objectives of this study were to evaluate the long-term effects of normal poultry litter, alum-treated litter, and ammonium nitrate (NH(4)NO(3)) on aluminum (Al) availability in soils, Al uptake by tall fescue (Festuca arundinacea Schreb.), and tall fescue yields. A long-term study was initiated in April of 1995. There were 13 treatments (unfertilized control, four rates of normal litter, four rates of alum-treated litter, and four rates of NH(4)NO(3)) in a randomized block design. All fertilizers were broadcast applied to 52 small plots (3.05 x 1.52 m) cropped to tall fescue annually in the spring. Litter application rates were 2.24, 4.49, 6.73, and 8.98 Mg ha(-1) (1, 2, 3, and 4 tons acre(-1)); NH(4)NO(3) rates were 65, 130, 195, and 260 kg N ha(-1) and were based on the amount of N applied with alum-treated litter. Soil pH, exchangeable Al (extracted with potassium chloride), Al uptake by fescue, and fescue yields were monitored periodically over time. Ammonium nitrate applications resulted in reductions in soil pH beginning in Year 3, causing exchangeable Al values to increase from less than 1 mg Al kg(-1) soil in Year 2 to over 100 mg Al kg(-1) soil in Year 7 for many of the NH(4)NO(3) plots. In contrast, normal and alum-treated litter resulted in an increase in soil pH, which decreased exchangeable Al when compared to unfertilized controls. Severe yield reductions were observed with NH(4)NO(3) beginning in Year 6, which were due to high levels of acidity and exchangeable Al. Aluminum uptake by forage and Al runoff from the plots were not affected by treatment. Fescue yields were highest with alum-treated litter (annual average = 7.36 Mg ha(-1)), followed by normal litter (6.93 Mg ha(-1)), NH(4)NO

  4. Experiment for Development of Simple Escape Countermeasures for Frogs Falling into Concrete Canals

    NASA Astrophysics Data System (ADS)

    Watabe, Keiji; Mori, Atsushi; Koizumi, Noriyuki; Takemura, Takeshi; Park, Myeong Soo

    Three prototype escape countermeasures for frogs that can be easily installed in U-shaped canals with widths of 30-50 cm and depths of 30-50 cm were experimentally produced because frogs cannot escape from agricultural canals with deep concrete walls after falling into the canal. The differences of effectiveness of the 3 prototypes in places for the countermeasures (1 and 2) and flow conditions (dry and water running) were investigated for 2 frog species (Tokyo Daruma Pond Frog and Japanese Brown Frog). The brown frogs escaped from the canals more easily than the pond frogs. The brown frogs escaped regardless of their body size, but the small pond frogs escaped more easily than the large pond frogs. The prototype with slopes beside both canal walls and a net spread across the center line of the canal enabled frogs to escape from the canal more easily than the prototypes with only slopes or nets beside both canal walls. Increasing the number of places for the countermeasures enhanced frog escape. The differences in frog escape between dry canals and canals with water running were not significant. Therefore, the prototypes were confirmed sufficient as escape countermeasures that is inexpensive and can be easily placed in and removed from agricultural canals.

  5. Ammonia and nitrous oxide emissions from broiler houses with downtime windrowed litter

    USDA-ARS?s Scientific Manuscript database

    An emerging poultry manure management practice is in house windrowing to disinfect the litter. With this practice, growers windrow the litter in broiler houses between flocks, usually for 2 weeks. This results in high litter temperatures that can reduce pathogens in the litter. However, this practi...

  6. Poultry litter placement effects on cotton seedling emergence and early growth stage

    USDA-ARS?s Scientific Manuscript database

    Interest in using poultry litter (PL) as a nutrient source for row crop production has increased in the Southeastern U.S. Poultry litter is generally broadcasted on the soil surface. This practice exposes litter N to volatilization and litter P to loss with surface water runoff, which potentially ne...

  7. Cotton response to poultry litter applied by subsurface banding relative to surface broadcasting

    USDA-ARS?s Scientific Manuscript database

    Dry poultry litter is typically land-applied by surface broadcasting, a practice that exposes certain litter nutrients to volatilization loss. Applying litter with a new, experimental implement that places the litter in narrow bands below the soil surface may reduce or eliminate such losses but has...

  8. Implement with adjustable band spacing for subsurface band application of poultry litter

    USDA-ARS?s Scientific Manuscript database

    Broiler litter is commonly used as a fertilizer on pastures and cropland. Poultry litter is typically land-applied by broadcasting the litter on the soil surface. Rain falling on soil to which poultry litter has been applied, may carry phosphorus (P) and nitrogen (N) nutrients from the soil into s...

  9. 9 CFR 82.7 - Interstate movement of manure and litter from a quarantined area.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... litter from a quarantined area. 82.7 Section 82.7 Animals and Animal Products ANIMAL AND PLANT HEALTH... Interstate movement of manure and litter from a quarantined area. (a) Manure generated by and litter used by... if: (1) The manure and litter is accompanied by a permit obtained in accordance with § 82.11; (2)...

  10. Composting and gypsum amendment of broiler litter to reduce nutrient leaching loss.

    PubMed

    Adeli, Ardeshir; Sheng, J; Jenkins, J N; Feng, G

    2015-03-01

    The effect of composted litter relative to fresh litter on leaching losses of nutrients has not been well documented. Fresh and composted broiler litter was surface-applied to bermudagrass (hay) [ (L.) Pers.] established in undisturbed soil columns based on N need of the grass in the presence or absence of flue gas desulfurization (FGD) gypsum to evaluate an approach to reduce broiler litter nutrient leaching potential. Columns were periodically leached and biomass was harvested during the 60-d experiment. Total N applied to bermudagrass from broiler litter was 320 kg ha. Gypsum was mixed with fresh and composted litter at the rate based on 20% of litter weight. For composted broiler litter, NO-N, P, K, Cu, and Zn contents in the leachate obtained from the first leaching event were 58, 50, 40, 32, and 38% less than fresh broiler litter, respectively. Significant decreases in NO-N (13%), P (53%), Cu (17%), and Zn (28%) in leachate were obtained when gypsum was mixed with fresh broiler litter. Fresh broiler litter and composted broiler litter applications increased bermudagrass growth compared with the control and gypsum significantly increased yields when mixed with broiler litter. Composted broiler litter application significantly increased N and organic C in the soil compared with fresh litter. Results demonstrate that coapplication of composted broiler litter with FGD gypsum provide the most effective management option for minimizing leaching losses of nutrients while sustaining crop productivity.

  11. Runoff quality from no-till cotton fertilized with broiler litter in subsurface bands

    USDA-ARS?s Scientific Manuscript database

    Surface broadcast of broiler litter to no-till row crops exposes broiler litter to the atmosphere and rain events, enhances the potential loss of nutrients to the air and surface runoff water and may limit benefit of litter to the crops. Subsurface banding of litter could alleviate these risks. A 2-...

  12. Soil-incorporating Poultry Litter Increases Cotton Tissue Nitrogen Concentration and Uptake

    USDA-ARS?s Scientific Manuscript database

    Applying poultry litter to fertilize no-till cotton implies the litter is left on the surface without soil-incorporation which exposes the litter and its nutrients to risks of loss in runoff water and volatilization. This research was conducted to test if light soil-incorporation of litter increases...

  13. Application of composted poultry litter as a fertilizer for landscape bedding plants

    USDA-ARS?s Scientific Manuscript database

    Each year, over 16 million tons of poultry litter is produced in the U.S. Federal and state regulations now limit the amount of poultry litter that can be land-applied, making it difficult to store and dispose poultry litter. The objective of this study was to evaluate composted poultry litter (CPL)...

  14. Greenhouse gas and ammonia emission from a litter-windrowing in bird houses

    USDA-ARS?s Scientific Manuscript database

    One of emerging poultry manure management practices is in house windrowing to disinfect the litter. With this practice, growers windrow the litter in broiler houses between flocks, usually for 2 weeks. This results in high litter temperatures that can reduce pathogens in the litter. However, this p...

  15. Distribution of plant nutrient elements and carbon in particle size fractions of broiler litter ash

    USDA-ARS?s Scientific Manuscript database

    An estimated 10.8 million tons of broiler litter and 3.0 million tons of turkey litter were produced in the United States in 2009. Poultry litter is a mixture of manure, bedding material (e.g., wood chips, sawdust, or straw), feathers, and spilled feed. Poultry litter contains high levels of Ca, N...

  16. Predation by Oregon spotted frogs (Rana pretiosa) on Western toads (Bufo boreas) in Oregon, USA

    USGS Publications Warehouse

    Pearl, Christopher A.; Hayes, M.P.

    2002-01-01

    Toads of the genus Bufo co-occur with true frogs (family Ranidae) throughout their North American ranges. Yet, Bufo are rarely reported as prey for ranid frogs, perhaps due to dermal toxins that afford them protection from some predators. We report field observations from four different localities demonstrating that Oregon spotted frogs (Rana pretiosa) readily consume juvenile western toads (Bufo boreas) at breeding sites in Oregon. Unpalatability thought to deter predators of selected taxa and feeding mode may not protect juvenile stages of western toads from adult Oregon spotted frogs. Activity of juvenile western toads can elicit ambush behavior by Oregon spotted frog adults. Our review of published literature suggests that regular consumption of toadlets sets Oregon spotted frogs apart from most North American ranid frogs. Importance of the trophic context of juvenile western toads as a seasonally important resource to Oregon spotted frogs needs critical investigation.

  17. How to Comply with Requirements to Protect California Red-legged Frog from Pesticides

    EPA Pesticide Factsheets

    This document describes buffer areas around certain habitats of the California red-legged frog, and limits on use of certain pesticides within those habitats and buffer zones to protect the red-legged frog from certain pesticides.

  18. Resurrecting an Extinct Species: Archival DNA, Taxonomy, and Conservation of the Vegas Valley Leopard Frog

    EPA Science Inventory

    Suggestions that the extinct Vegas Valley leopard frog (Rana fisheri = Lithobates fisheri) may have been synonymous with one of several declining species has complicated recovery planning for imperiled leopard frogs in southwestern North America. To address this concern, we recon...

  19. Resurrecting an Extinct Species: Archival DNA, Taxonomy, and Conservation of the Vegas Valley Leopard Frog

    EPA Science Inventory

    Suggestions that the extinct Vegas Valley leopard frog (Rana fisheri = Lithobates fisheri) may have been synonymous with one of several declining species has complicated recovery planning for imperiled leopard frogs in southwestern North America. To address this concern, we recon...

  20. Cystic urolithiasis in captive waxy monkey frogs (Phyllomedusa sauvagii).

    PubMed

    Archibald, Kate E; Minter, Larry J; Dombrowski, Daniel S; O'Brien, Jodi L; Lewbart, Gregory A

    2015-03-01

    The waxy monkey frog (Phyllomedusa sauvagii) is an arboreal amphibian native to arid regions of South America, and it has developed behavioral and physiologic adaptations to permit survival in dry environments. These adaptations include a uricotelic nitrogen metabolism and unique cutaneous lipid excretions to prevent evaporative water loss. Uroliths are a rare finding in amphibians. Six adult, presumed wild-caught waxy monkey frogs housed in a museum animal collection were diagnosed with cystic urolithiasis over a 7-yr period, and a single animal was diagnosed with four recurrent cases. Six cases were identified incidentally at routine physical or postmortem examination and four cases were identified during veterinary evaluation for coelomic distension, lethargy, anorexia, and increased soaking behavior. Calculi were surgically removed from three frogs via cystotomy, and a single frog underwent three cystotomies and two cloacotomies for recurrent urolithiasis. Two frogs died within the 24-hr postoperative period. Two representative calculi from a single frog were submitted for component analysis and found to consist of 100% ammonium urate. In the present report, cystic calculi are proposed to be the result of a high-protein diet based on a single invertebrate source, coupled with uricotelism, dehydration, increased cutaneous water loss, body temperature fluctuations facilitating supersaturation of urine, and subsequent accumulation and precipitation of urogenous wastes within the urinary bladder. Surgical cystotomy represents a short-term treatment strategy for this condition. Preventative measures, such as supplying a diversified and balanced diet in addition to environmental manipulation aimed at promoting adequate hydration, are anticipated to be more-rewarding management tools for cystic urolithiasis in the waxy monkey frog.

  1. Phylogeny and biogeography of South Chinese brown frogs (Ranidae, Anura).

    PubMed

    Zhou, Yu; Wang, Sirui; Zhu, Hedan; Li, Pipeng; Yang, Baotian; Ma, Jianzhang

    2017-01-01

    Few studies have explored the role of Cenozoic tectonic evolution in shaping the patterns and processes of extant animal distributions in and around East Asia. In this study, we selected South Chinese brown frogs as a model to examine the phylogenetic and biogeographical consequences of Miocene tectonic events within South China and its margins. We used mitochondrial and nuclear molecular data to reconstruct phylogenetic interrelationships among Chinese brown frogs using Bayesian and maximum likelihood analyses. The phylogeny results show that there are four main clades of Chinese brown frogs. Excepting the three commonly known Chinese brown frog species groups, R. maoershanensis forms an independent clade nearest to the R. japonica group. Phylogeny and P-distance analyses confirmed R. maoershanensis as a valid species. Among South Chinese brown frogs, there are four subclades associated with four geographical areas: (I) R. maoershanensis; (II) R. japonica; (III) R. chaochiaoensis; and (IV) other species of the R. longicrus species group. Divergence times, estimated using mitochondrial sequences, place the vicariance events among the four subclades in the middle to late Miocene epoch. Our results suggest that (1) South Chinese brown frogs originated due to a vicariance event separating them from the R. chensinensis species group at the time of the Geological movement (~18 million years ago, Ma) in southern Tibet and the Himalayan region; (2) the separation and speciation of R. maoershanensis from the R. japonica group occurred due to the dry climate at approximately 16 Ma; (3) South Chinese brown frogs migrated from South China to Japan at the time (~10.8 Ma) that the global sea-level fell and the East China Sea Shelf Basin was swamp facies, when a land gallery may have formed across the sea to connect the two areas; and (4) R. chaochiaoensis separated from other species of the R. longicrus species group during the uplift of the Tibetan Plateau at approximately 9

  2. Phylogeny and biogeography of South Chinese brown frogs (Ranidae, Anura)

    PubMed Central

    Wang, Sirui; Zhu, Hedan; Li, Pipeng; Yang, Baotian; Ma, Jianzhang

    2017-01-01

    Few studies have explored the role of Cenozoic tectonic evolution in shaping the patterns and processes of extant animal distributions in and around East Asia. In this study, we selected South Chinese brown frogs as a model to examine the phylogenetic and biogeographical consequences of Miocene tectonic events within South China and its margins. We used mitochondrial and nuclear molecular data to reconstruct phylogenetic interrelationships among Chinese brown frogs using Bayesian and maximum likelihood analyses. The phylogeny results show that there are four main clades of Chinese brown frogs. Excepting the three commonly known Chinese brown frog species groups, R. maoershanensis forms an independent clade nearest to the R. japonica group. Phylogeny and P-distance analyses confirmed R. maoershanensis as a valid species. Among South Chinese brown frogs, there are four subclades associated with four geographical areas: (I) R. maoershanensis; (II) R. japonica; (III) R. chaochiaoensis; and (IV) other species of the R. longicrus species group. Divergence times, estimated using mitochondrial sequences, place the vicariance events among the four subclades in the middle to late Miocene epoch. Our results suggest that (1) South Chinese brown frogs originated due to a vicariance event separating them from the R. chensinensis species group at the time of the Geological movement (~18 million years ago, Ma) in southern Tibet and the Himalayan region; (2) the separation and speciation of R. maoershanensis from the R. japonica group occurred due to the dry climate at approximately 16 Ma; (3) South Chinese brown frogs migrated from South China to Japan at the time (~10.8 Ma) that the global sea-level fell and the East China Sea Shelf Basin was swamp facies, when a land gallery may have formed across the sea to connect the two areas; and (4) R. chaochiaoensis separated from other species of the R. longicrus species group during the uplift of the Tibetan Plateau at approximately 9

  3. Panamanian frog species host unique skin bacterial communities

    PubMed Central

    Belden, Lisa K.; Hughey, Myra C.; Rebollar, Eria A.; Umile, Thomas P.; Loftus, Stephen C.; Burzynski, Elizabeth A.; Minbiole, Kevin P. C.; House, Leanna L.; Jensen, Roderick V.; Becker, Matthew H.; Walke, Jenifer B.; Medina, Daniel; Ibáñez, Roberto; Harris, Reid N.

    2015-01-01

    Vertebrates, including amphibians, host diverse symbiotic microbes that contribute to host disease resistance. Globally, and especially in montane tropical systems, many amphibian species are threatened by a chytrid fungus, Batrachochytrium dendrobatidis (Bd), that causes a lethal skin disease. Bd therefore may be a strong selective agent on the diversity and function of the microbial communities inhabiting amphibian skin. In Panamá, amphibian population declines and the spread of Bd have been tracked. In 2012, we completed a field survey in Panamá to examine frog skin microbiota in the context of Bd infection. We focused on three frog species and collected two skin swabs per frog from a total of 136 frogs across four sites that varied from west to east in the time since Bd arrival. One swab was used to assess bacterial community structure using 16S rRNA amplicon sequencing and to determine Bd infection status, and one was used to assess metabolite diversity, as the bacterial production of anti-fungal metabolites is an important disease resistance function. The skin microbiota of the three Panamanian frog species differed in OTU (operational taxonomic unit, ~bacterial species) community composition and metabolite profiles, although the pattern was less strong for the metabolites. Comparisons between frog skin bacterial communities from Panamá and the US suggest broad similarities at the phylum level, but key differences at lower taxonomic levels. In our field survey in Panamá, across all four sites, only 35 individuals (~26%) were Bd infected. There was no clustering of OTUs or metabolite profiles based on Bd infection status and no clear pattern of west-east changes in OTUs or metabolite profiles across the four sites. Overall, our field survey data suggest that different bacterial communities might be producing broadly similar sets of metabolites across frog hosts and sites. Community structure and function may not be as tightly coupled in these skin symbiont

  4. Broiler litter ammonia emissions near sidewalls, feeders and waterers

    USDA-ARS?s Scientific Manuscript database

    Ammonia (NH3) volatilized from broiler litter diminishes indoor air quality which can potentially decrease bird productivity. Emissions of NH3 exhausted from broiler houses pose environmental concerns for ecosystem biodiversity, aquatic nutrient enrichment and particulate formation in the atmospher...

  5. Effect of ponderosa pine needle litter on grass seedling survival.

    Treesearch

    Burt R. McConnell; Justin G. Smith

    1971-01-01

    Hard fescue survival rates were followed for 6 years on four different pine needle treatment plots. Needle litter had a significant effect on initial survival of fescue seedlings, but subsequent losses undoubtedly resulted from the interaction of many factors.

  6. Complete mitochondrial genome of the Greek marsh frog Pelophylax cretensis (Anura, Ranidae).

    PubMed

    Hofman, Sebastian; Pabijan, Maciej; Osikowski, Artur; Szymura, Jacek M

    2016-05-01

    We sequenced the complete mitochondrial genome of the Greek marsh frog Pelophylax cretensis, a water frog species endemic to the island of Crete. The genome sequence was 17,829 bp in size, and the gene order and contents were identical to those of previously reported mitochondrial genomes of other water frog species. This is the first complete mitogenome (i.e. including control region) described for western Palaearctic water frogs.

  7. Interventions to reduce the bacterial load in recycled broiler litter.

    PubMed

    Vaz, C S L; Voss-Rech, D; de Avila, V S; Coldebella, A; Silva, V S

    2017-03-23

    Two experiments were undertaken to evaluate the bacterial load in recycled litter between broiler flocks following addition of quicklime (T1), windrowing (T2), shallow fermentation (T3), and control (no intervention, T4). The first experiment was developed in field conditions in which the broiler houses were accompanied by 6 consecutive flocks and the effect of the treatments was assessed on enterobacteria and aerobic mesophiles. The second experiment was conducted in an experimental broiler house with recycled litter for assessment of Salmonella Enteritidis phage type 4 (SE PT4). In the field study, T3 presented the best results in reducing enterobacteria in broiler litter in relation to the other treatments, with the highest reduction occurring in the first 3 flocks, tending to stabilization from the fourth flock onward for all the treatments assessed. From the third to sixth flocks, enterobacteria level at the end of the treatments (d 12) was lower than the average in the fresh litter, except in T4. All treatments reduced aerobic mesophiles throughout the flocks, where T2 showed the highest reduction. The percentage of dry matter in the broiler litter diminished in T4 and increased in T3 over the course of the flocks. In the second experiment, the drop in the SE PT4 level in the broiler litter first occurred in T2 and T3. However, all the treatments except for T4 eliminated SE PT4 within 12 d. The temperature of the broiler litter in T2 was higher in relation to the other treatments. The results show that litter treatment prior to reutilization by the successive broiler flock is required to reduce the level of residual bacteria. The fermentative treatments (T2 and T3) were found to be superior to the others in terms of reducing the bacterial load, with shallow fermentation standing out with the highest reduction of enterobacteria and equivalent SE PT4 elimination when compared to windrowing.

  8. Plant Litter Submergence Affects the Water Quality of a Constructed Wetland.

    PubMed

    Pan, Xu; Ping, Yunmei; Cui, Lijuan; Li, Wei; Zhang, Xiaodong; Zhou, Jian; Yu, Fei-Hai; Prinzing, Andreas

    2017-01-01

    Plant litter is an indispensable component of constructed wetlands, but how the submergence of plant litter affects their ecosystem functions and services, such as water purification, is still unclear. Moreover, it is also unclear whether the effects of plant litter submergence depend on other factors such as the duration of litter submergence, water source or litter species identity. Here we conducted a greenhouse experiment by submerging the litter of 7 wetland plant species into three types of water substrates and monitoring changes in water nutrient concentrations. Litter submergence affected water quality positively via decreasing the concentration of nitrate nitrogen and negatively via increasing the concentrations of total nitrogen, ammonium nitrogen and total phosphorus. The effects of litter submergence depended on the duration of litter submergence, the water source, the litter species identity, and the plant life form. Different plant species had different effects on the water nutrient concentrations during litter submergence, and the effects of floating plants might be more negative than that of emergent plants. These results are novel evidence of how the submergence of different plant (life form) litter may affect the purification function of constructed wetlands. For water at low eutrophication levels, submerging a relative small amount of plant litter might improve water quality, via benefiting the denitrification process in water. These findings emphasized the management of floating plant litter (a potential removal) during the maintenance of human-controlled wetland ecosystems and provided a potential tool to improve the water quality of constructed wetlands via submerging plant litter of different types.

  9. Guinea Worm (Dracunculus medinensis) Infection in a Wild-Caught Frog, Chad.

    PubMed

    Eberhard, Mark L; Cleveland, Christopher A; Zirimwabagabo, Hubert; Yabsley, Michael J; Ouakou, Philippe Tchindebet; Ruiz-Tiben, Ernesto

    2016-11-01

    A third-stage (infective) larva of Dracunculus medinensis, the causative agent of Guinea worm disease, was recovered from a wild-caught Phrynobatrachus francisci frog in Chad. Although green frogs (Lithobates clamitans) have been experimentally infected with D. medinensis worms, our findings prove that frogs can serve as natural paratenic hosts.

  10. Enterobacteriaceae and Aeromonas hydrophila in Minnesota frogs and tadpoles (Rana pipiens).

    PubMed Central

    Hird, D W; Diesch, S L; McKinnell, R G; Gorham, E; Martin, F B; Meadows, C A; Gasiorowski, M

    1983-01-01

    In 222 Rana pipiens frogs and 34 tadpoles captured in and near Minnesota, Aeromonas hydrophila and 29 species of Enterobacteriaceae, including yersinia enterocolitica and Salmonella arizonae, were isolated from intestines. The prevalence of members of the family Enterobacteriaceae was lowest in frogs captured in early spring and highest in frogs captured in late summer. PMID:6607034

  11. Guinea Worm (Dracunculus medinensis) Infection in a Wild-Caught Frog, Chad

    PubMed Central

    Cleveland, Christopher A.; Zirimwabagabo, Hubert; Yabsley, Michael J.; Ouakou, Philippe Tchindebet; Ruiz-Tiben, Ernesto

    2016-01-01

    A third-stage (infective) larva of Dracunculus medinensis, the causative agent of Guinea worm disease, was recovered from a wild-caught Phrynobatrachus francisci frog in Chad. Although green frogs (Lithobates clamitans) have been experimentally infected with D. medinensis worms, our findings prove that frogs can serve as natural paratenic hosts. PMID:27560598

  12. The Funeral of Froggy the Frog: The Child as Dramatist, Designer, and Realist

    ERIC Educational Resources Information Center

    Cummins, Lauren

    2004-01-01

    One sunny afternoon, six-year-old Zachary and his friend John Michael, four and a half, discovered a dead frog in a bag of clay in the garage. Zachary proposed, "Let's have a funeral for the frog." This is how the funeral drama of Froggy the Frog began. This article describes the play experiences of Zachary and John Michael as designers,…

  13. Effects of the Chytrid fungus on the Tarahumara frog (Rana tarahumarae) in Arizona and Sonora, Mexico

    Treesearch

    Stephen F. Hale; Philip C. Rosen; James L. Jarchow; Gregory A. Bradley

    2005-01-01

    We conducted histological analyses on museum specimens collected 1975-1999 from 10 sites in Arizona and Sonora to test for the pathogenic chytrid fungus (Batrachochytrium dendrobatidis) in ranid frogs, focusing on the Tarahumara frog (Rana tarahumarae). During 1981-2000, frogs displaying disease signs were found in the field, and...

  14. 49 CFR 213.143 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Frog guard rails and guard faces; gage. 213.143... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.143 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs shall be within the limits...

  15. 49 CFR 236.327 - Switch, movable-point frog or split-point derail.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Switch, movable-point frog or split-point derail..., AND APPLIANCES Interlocking Rules and Instructions § 236.327 Switch, movable-point frog or split-point derail. Switch, movable-point frog, or split-point derail equipped with lock rod shall be maintained so...

  16. 49 CFR 236.327 - Switch, movable-point frog or split-point derail.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Switch, movable-point frog or split-point derail..., AND APPLIANCES Interlocking Rules and Instructions § 236.327 Switch, movable-point frog or split-point derail. Switch, movable-point frog, or split-point derail equipped with lock rod shall be maintained so...

  17. The Funeral of Froggy the Frog: The Child as Dramatist, Designer, and Realist

    ERIC Educational Resources Information Center

    Cummins, Lauren

    2004-01-01

    One sunny afternoon, six-year-old Zachary and his friend John Michael, four and a half, discovered a dead frog in a bag of clay in the garage. Zachary proposed, "Let's have a funeral for the frog." This is how the funeral drama of Froggy the Frog began. This article describes the play experiences of Zachary and John Michael as designers,…

  18. 49 CFR 213.143 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Frog guard rails and guard faces; gage. 213.143... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.143 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs shall be within the limits...

  19. 49 CFR 213.143 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Frog guard rails and guard faces; gage. 213.143... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.143 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs shall be within the limits...

  20. 49 CFR 236.327 - Switch, movable-point frog or split-point derail.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Switch, movable-point frog or split-point derail..., AND APPLIANCES Interlocking Rules and Instructions § 236.327 Switch, movable-point frog or split-point derail. Switch, movable-point frog, or split-point derail equipped with lock rod shall be maintained so...

  1. 49 CFR 213.143 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Frog guard rails and guard faces; gage. 213.143... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.143 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs shall be within the limits...

  2. 49 CFR 236.327 - Switch, movable-point frog or split-point derail.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Switch, movable-point frog or split-point derail..., AND APPLIANCES Interlocking Rules and Instructions § 236.327 Switch, movable-point frog or split-point derail. Switch, movable-point frog, or split-point derail equipped with lock rod shall be maintained so...

  3. 75 FR 8733 - Least Chub and Columbia Spotted Frog Candidate Conservation Agreement With Assurances; Receipt of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-25

    ... Fish and Wildlife Service Least Chub and Columbia Spotted Frog Candidate Conservation Agreement With... (CCAA) for the least chub (Iotichthys phlegethontis) and Columbia spotted frog (Rana lutreiventris..., least chub and Columbia spotted frog inhabited a variety of aquatic habitat types throughout the...

  4. 49 CFR 236.327 - Switch, movable-point frog or split-point derail.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Switch, movable-point frog or split-point derail..., AND APPLIANCES Interlocking Rules and Instructions § 236.327 Switch, movable-point frog or split-point derail. Switch, movable-point frog, or split-point derail equipped with lock rod shall be maintained so...

  5. 49 CFR 213.143 - Frog guard rails and guard faces; gage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Frog guard rails and guard faces; gage. 213.143... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.143 Frog guard rails and guard faces; gage. The guard check and guard face gages in frogs shall be within the limits...

  6. Consequences of biodiversity loss for litter decomposition across biomes.

    PubMed

    Handa, I Tanya; Aerts, Rien; Berendse, Frank; Berg, Matty P; Bruder, Andreas; Butenschoen, Olaf; Chauvet, Eric; Gessner, Mark O; Jabiol, Jérémy; Makkonen, Marika; McKie, Brendan G; Malmqvist, Björn; Peeters, Edwin T H M; Scheu, Stefan; Schmid, Bernhard; van Ruijven, Jasper; Vos, Veronique C A; Hättenschwiler, Stephan

    2014-05-08

    The decomposition of dead organic matter is a major determinant of carbon and nutrient cycling in ecosystems, and of carbon fluxes between the biosphere and the atmosphere. Decomposition is driven by a vast diversity of organisms that are structured in complex food webs. Identifying the mechanisms underlying the effects of biodiversity on decomposition is critical given the rapid loss of species worldwide and the effects of this loss on human well-being. Yet despite comprehensive syntheses of studies on how biodiversity affects litter decomposition, key questions remain, including when, where and how biodiversity has a role and whether general patterns and mechanisms occur across ecosystems and different functional types of organism. Here, in field experiments across five terrestrial and aquatic locations, ranging from the subarctic to the tropics, we show that reducing the functional diversity of decomposer organisms and plant litter types slowed the cycling of litter carbon and nitrogen. Moreover, we found evidence of nitrogen transfer from the litter of nitrogen-fixing plants to that of rapidly decomposing plants, but not between other plant functional types, highlighting that specific interactions in litter mixtures control carbon and nitrogen cycling during decomposition. The emergence of this general mechanism and the coherence of patterns across contrasting terrestrial and aquatic ecosystems suggest that biodiversity loss has consistent consequences for litter decomposition and the cycling of major elements on broad spatial scales.

  7. The influence of variation in litter habitats on spider communities.

    PubMed

    Uetz, George W

    1979-01-01

    Spider communities were sampled over an artificial gradient of litter depth (created by raking) and compared to those of two other forests exhibiting natural variation in litter depth. More species of spiders were present in areas of greater depth and/or complexity in all sites. Relative abundance of Lycosidae decreased, while relative abundance of Clubionidae, Thomisidae and Gnaphosidae increased over gradients of increasing depth and complexity. Similarity of species composition between areas within a forest was related to site differences in litter depth and structure.As litter depth increased, there were significant changes in prey species richness, litter complexity, and microclimate. Partial correlation analysis of grouped data from early-, mid-, and late season suggests that influential factors change with season. In the early season, prey abundance and temperature variation account for most of the variation in spider species richness. In mid-season, litter complexity and moisture fluctuations appear to influence richness, with complexity relatively more important. In late season, complexity and temperature range were the primary factors, with temperature relatively more influential. The relative importance of these factors in influencing community structure of spiders is discussed.

  8. Survival of coccidia in poultry litter and reservoirs of infection.

    PubMed

    Reyna, P S; McDougald, L R; Mathis, G F

    1983-01-01

    The survival of coccidia was studied in poultry litter, dust, soil, and invertebrate animals. The populations of coccidia in litter were recorded during broiler growout in 16 broiler houses and in floor-pen trials involving anticoccidial drugs. The viability of oocysts declined rapidly in poultry litter regardless of the species; it was retained best in 40% moisture at 4 C. Sporocysts from broken oocytes did not survive even short exposure to poultry litter. Survival of oocysts was poorest at temperatures higher than 4 C, regardless of the carrier. In four floor-pen experiments designed to study the efficacy of anticoccidial drugs, the oocyst counts correlated in a general way with lesion scores and performance, indicating the oocyst counts might be useful along with other parameters to judge the effectiveness of drugs. Coccidia were transmitted to susceptible chicks by feeding them darkling beetles, flies, or house dust from poultry houses. More carrier samples were positive during the warmer months. Oocyst counts in litter of commercial poultry houses were very low during the first or last weeks of broiler growout but were high during the normal 3-to-6-week stress period. These results confirm the poor survival of oocysts in poultry litter and suggest that carryover from one flock to the next depends on the survival of a few oocysts in dust or arthropod vectors.

  9. Invertebrate grazers affect metal/metalloid fixation during litter decomposition.

    PubMed

    Schaller, Jörg; Brackhage, Carsten

    2015-01-01

    Plant litter and organic sediments are main sinks for metals and metalloids in aquatic ecosystems. The effect of invertebrates as key species in aquatic litter decomposition on metal/metalloid fixation by organic matter is described only for shredders, but for grazers as another important animal group less is known. Consequently, a laboratory batch experiment was conducted to examine the effect of invertebrate grazers (Lymnaea stagnalis L.) on metal/metalloid fixation/remobilization during aquatic litter decomposition. It could be shown that invertebrate grazers facilitate significantly the formation of smaller sizes of particulate organic matter (POM), as shown previously for invertebrate shredders. The metal/metalloid binding capacity of these smaller particles of POM is higher compared to leaf litter residuals. But element enrichment is not as high as shown previously for the effect by invertebrate shredders. Invertebrate grazers enhance also the mobilization of selected elements to the water, in the range also proven for invertebrate shredders but different for the different elements. Nonetheless invertebrate grazers activity during aquatic litter decomposition leads to a metal/metalloid fixation into leaf litter as part of sediment organic matter. Hence, the effect of invertebrate grazers on metal/metalloid fixation/remobilization contrasts partly with former assessments revealing the possibility of an enhanced metal/metalloid fixation.

  10. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    SciTech Connect

    Dr. Kalyan Annamalai; Dr. John Sweeten; Dr. Sayeed Mukhtar

    2001-02-05

    The following are proposed activities for quarter 2 (9/15/00-12/14/00): (1) Conduct TGA and fuel characterization studies--Task 1; (2) Perform re-burn experiments--Task 2; (3) Fabricate fixed bed gasifier/combustor--Task 3; and (4) Modify the 3D combustion modeling code for feedlot and litter fuels--Task 4. The following were achieved During Quarter 2 (9/15/00-12/14/00): (1) The chicken litter has been obtained from Sanderson farms in Denton, after being treated with a cyclonic dryer. The litter was then placed into steel barrels and shipped to California to be pulverized in preparation for firing. Litter samples have also been sent for ultimate/proximate laboratory analyses.--Task 1; (2) Reburn-experiments have been conducted on coal, as a base case for comparison to litter biomass. Results will be reported along with litter biomass as reburn fuel in the next report--Task 2; (3) Student has not yet been hired to perform task 3. Plans are ahead to hire him or her during quarter No. 3; and (4) Conducted a general mixture fraction model for possible incorporation in the code.

  11. Comparison of litter adjustment factors in Yorkshire and Landrace data.

    PubMed

    Brubaker, M; Lofgren, D; Einstein, M; Stewart, T

    1994-10-01

    National Swine Improvement Federation (NSIF) adjustment factors presently used to standardize litter data for age at 21 d, number born alive (NBA), 21-d litter weight, and number after transfer (NAT) were evaluated using 104,884 litters in 1,348 Yorkshire herds and 20,370 litters in 197 Landrace herds. In addition, adjustment factors for number weaned were calculated for standardization of this trait. Number weaned is adjusted for parity and NAT. The mixed-model least squares, maximum likelihood computer program described by Harvey was used in the analyses. Yorkshire and Landrace data were combined to test for breed effects and interactions involving breed. Breed interactions were different (P < .05). Therefore, breed-specific adjustment factors were calculated for Yorkshire and Landrace data sets. Also, adjustment factors were calculated for combined data that might be appropriate to use for breeds without specific adjustments available. Parity adjustment factors for NBA and 21-d litter weight were different (P < .05) from current NSIF recommendations, as was the NAT adjustment for 21-d litter weight. The age-at-weaning multiplicative factors were not different (P > .05) from current NSIF values. However, in all three data sets, the intercepts and linear coefficients of the quadratic regression for age at weaning were different (P < .05) from NSIF's. A Student-Newman-Keuls (SNK) test was used to evaluate the NSIF groupings of parity and number after transfer.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Litter decomposition patterns in a semiarid Mediterranean ecosystem

    NASA Astrophysics Data System (ADS)

    María, Almagro; Jorge, López; María, Martínez-Mena

    2010-05-01

    Accumulation of soil carbon is mainly controlled by the balance between litter production and litter decomposition. While aboveground litter decomposition in mesic systems is thought to be controlled by climate, litter quality, and soil faunal interactions (Aerts, 1997), it is becoming increasingly evident that factors other than water availability, including photodegradation, physical fragmentation of litter, and soil movement may play central roles in determining rates of carbon and nutrient turnover in arid and semiarid ecosystems (Whitford et al., 2002; Austin and Vivanco, 2006; Throop and Archer, 2007). Decomposition and its controls were studied using the litter-bag method by exposing two different litter types (Pinus halepensis Mill. and Rosmarinus officinalis Linn.) for a 20 month period in two Mediterranean ecosystems of the eastern Iberian Peninsula: 1) a ~ 150-yr-old forest stand, and 2) an abandoned agricultural field. Both sites are covered by a typical Mediterranean shrubland (Rosmarinus officinalis, Quercus coccifera, and Juniperus oxycedrus) with scattered Aleppo pines (Pinus halepensis). A single exponential decay model (Olson, 1963) fit the data well (R2 values ranging from 0.46 to 0.82). Litter types differed in their decomposition dynamics despite of similar initial content of C and N, and C:N ratios. Rosemary litter decomposed more rapidly than Aleppo pine litter across sites (R2 = 0.742; F= 132.18; P<0.0001). After 20 months, rosemary litterbags had significantly less mass than did Aleppo pine litterbags regardless of site (pooled across sites: rosemary = 44.77% ± 2.21% (mean ± SE), Aleppo pine = 70.25 % ± 2.21% (mean ± SE); F= 132.18; P<0.0001). There was also a significant site effect on decomposition rates. While P. halepensis litter decomposed 1.5 fold-more rapidly (R2= 0.68; F= 45.93; P<0.0001), R. officinalis litter decay rates were 1.2 fold-higher in forest than in abandoned field site. Soil temperature or water availability could

  13. Sophisticated Communication in the Brazilian Torrent Frog Hylodes japi.

    PubMed

    de Sá, Fábio P; Zina, Juliana; Haddad, Célio F B

    2016-01-01

    Intraspecific communication in frogs plays an important role in the recognition of conspecifics in general and of potential rivals or mates in particular and therefore with relevant consequences for pre-zygotic reproductive isolation. We investigate intraspecific communication in Hylodes japi, an endemic Brazilian torrent frog with territorial males and an elaborate courtship behavior. We describe its repertoire of acoustic signals as well as one of the most complex repertoires of visual displays known in anurans, including five new visual displays. Previously unknown in frogs, we also describe a bimodal inter-sexual communication system where the female stimulates the male to emit a courtship call. As another novelty for frogs, we show that in addition to choosing which limb to signal with, males choose which of their two vocal sacs will be used for visual signaling. We explain how and why this is accomplished. Control of inflation also provides additional evidence that vocal sac movement and color must be important for visual communication, even while producing sound. Through the current knowledge on visual signaling in Neotropical torrent frogs (i.e. hylodids), we discuss and highlight the behavioral diversity in the family Hylodidae. Our findings indicate that communication in species of Hylodes is undoubtedly more sophisticated than we expected and that visual communication in anurans is more widespread than previously thought. This is especially true in tropical regions, most likely due to the higher number of species and phylogenetic groups and/or to ecological factors, such as higher microhabitat diversity.

  14. Tourism and the Conservation of Critically Endangered Frogs

    PubMed Central

    Morrison, Clare; Simpkins, Clay; Castley, J. Guy; Buckley, Ralf C.

    2012-01-01

    Protected areas are critical for the conservation of many threatened species. Despite this, many protected areas are acutely underfunded, which reduces their effectiveness significantly. Tourism is one mechanism to promote and fund conservation in protected areas, but there are few studies analyzing its tangible conservation outcomes for threatened species. This study uses the 415 IUCN critically endangered frog species to evaluate the contribution of protected area tourism revenue to conservation. Contributions were calculated for each species as the proportion of geographic range inside protected areas multiplied by the proportion of protected area revenues derived from tourism. Geographic ranges were determined from IUCN Extent of Occurrence maps. Almost 60% (239) of critically endangered frog species occur in protected areas. Higher proportions of total range are protected in Nearctic, Australasian and Afrotopical regions. Tourism contributions to protected area budgets ranged from 5–100%. These financial contributions are highest for developing countries in the Afrotropical, Indomalayan and Neotropical regions. Data for both geographic range and budget are available for 201 critically endangered frog species with proportional contributions from tourism to species protection ranging from 0.8–99%. Tourism's financial contributions to critically endangered frog species protection are highest in the Afrotropical region. This study uses a coarse measure but at the global scale it demonstrates that tourism has significant potential to contribute to global frog conservation efforts. PMID:22984440

  15. Efficacy of frog skin lipids in wound healing

    PubMed Central

    2010-01-01

    Background Frog skin has been sequentially and scientifically evaluated by our group for its wound healing efficiency. Owing to the complex structure of skin, attempts were being made to analyse the role of individual constituents in different phases of healing. Our earlier papers have shown the significance of frog skin not only in wound healing but also enhancing the proliferating activity of the epidermal and dermal cells which are instrumental for normal healing process. We also have identified for the first time novel antimicrobial peptides from the skin of Rana tigerina and thereby reduce the complications involved in the sepsis. Purpose of the study and Results The current study envisages the role of frog skin lipids in the inflammatory phase of wound healing. The lipid moiety of the frog skin dominated by phospholipids exhibited a dose dependent acceleration of healing irrespective of the mode of application. The efficiency of the extract is attributed partially to the anti-inflammatory activity as observed by the histochemical and immunostimulatory together with plethysmographic studies. Conclusions Thus, frog skin for the first time has been demonstrated to possess lipid components with pharmaceutical and therapeutic potential. The identification and characterization of such natural healing molecules and evaluating their mechanism of action would therefore provide basis for understanding the cues of Nature and hence can be used for application in medicine. PMID:20637131

  16. Tourism and the conservation of critically endangered frogs.

    PubMed

    Morrison, Clare; Simpkins, Clay; Castley, J Guy; Buckley, Ralf C

    2012-01-01

    Protected areas are critical for the conservation of many threatened species. Despite this, many protected areas are acutely underfunded, which reduces their effectiveness significantly. Tourism is one mechanism to promote and fund conservation in protected areas, but there are few studies analyzing its tangible conservation outcomes for threatened species. This study uses the 415 IUCN critically endangered frog species to evaluate the contribution of protected area tourism revenue to conservation. Contributions were calculated for each species as the proportion of geographic range inside protected areas multiplied by the proportion of protected area revenues derived from tourism. Geographic ranges were determined from IUCN Extent of Occurrence maps. Almost 60% (239) of critically endangered frog species occur in protected areas. Higher proportions of total range are protected in Nearctic, Australasian and Afrotopical regions. Tourism contributions to protected area budgets ranged from 5-100%. These financial contributions are highest for developing countries in the Afrotropical, Indomalayan and Neotropical regions. Data for both geographic range and budget are available for 201 critically endangered frog species with proportional contributions from tourism to species protection ranging from 0.8-99%. Tourism's financial contributions to critically endangered frog species protection are highest in the Afrotropical region. This study uses a coarse measure but at the global scale it demonstrates that tourism has significant potential to contribute to global frog conservation efforts.

  17. Drainage ditches facilitate frog movements in a hostile landscape

    USGS Publications Warehouse

    Mazerolle, M.J.

    2005-01-01

    Ditches are common in landscapes influenced by agricultural, forestry, and peat mining activities, and their value as corridors remains unassessed. Pond-breeding amphibians can encounter hostile environments when moving between breeding, summering, or hibernation sites, and are likely to benefit from the presence of ditches in the landscape. Within a system consisting of ditch networks in bogs mined for peat in eastern New Brunswick, Canada, I quantified the breeding, survival, and movements of green frogs (Rana clamitans melanota) in drainage ditches and also surveyed peat fields. Frogs rarely ventured on peat fields and most individuals frequented drainage ditches containing water, particularly in late summer. Though frogs did not breed in ditches, their survival rate in ditches was high (88%). Ditches did not hinder frog movements, as frogs moved independently of the current. Results indicate that drainage ditches containing water enable some movements between habitats isolated by peat mining, in contrast to peat surfaces, and suggest they function as amphibian movement corridors. Thus, such drainage ditches may mitigate the effects of peat extraction on amphibian populations. At the very least, these structures provide an alternative to hostile peat surfaces. This study highlights that small-scale corridors are potentially valuable in population dynamics. ?? Springer 2005.

  18. Frog sound identification using extended k-nearest neighbor classifier

    NASA Astrophysics Data System (ADS)

    Mukahar, Nordiana; Affendi Rosdi, Bakhtiar; Athiar Ramli, Dzati; Jaafar, Haryati

    2017-09-01

    Frog sound identification based on the vocalization becomes important for biological research and environmental monitoring. As a result, different types of feature extractions and classifiers have been employed to evaluate the accuracy of frog sound identification. This paper presents a frog sound identification with Extended k-Nearest Neighbor (EKNN) classifier. The EKNN classifier integrates the nearest neighbors and mutual sharing of neighborhood concepts, with the aims of improving the classification performance. It makes a prediction based on who are the nearest neighbors of the testing sample and who consider the testing sample as their nearest neighbors. In order to evaluate the classification performance in frog sound identification, the EKNN classifier is compared with competing classifier, k -Nearest Neighbor (KNN), Fuzzy k -Nearest Neighbor (FKNN) k - General Nearest Neighbor (KGNN)and Mutual k -Nearest Neighbor (MKNN) on the recorded sounds of 15 frog species obtained in Malaysia forest. The recorded sounds have been segmented using Short Time Energy and Short Time Average Zero Crossing Rate (STE+STAZCR), sinusoidal modeling (SM), manual and the combination of Energy (E) and Zero Crossing Rate (ZCR) (E+ZCR) while the features are extracted by Mel Frequency Cepstrum Coefficient (MFCC). The experimental results have shown that the EKNCN classifier exhibits the best performance in terms of accuracy compared to the competing classifiers, KNN, FKNN, GKNN and MKNN for all cases.

  19. Marsh frogs, Pelophylax ridibundus, determine migratory direction by magnetic field.

    PubMed

    Shakhparonov, Vladimir V; Ogurtsov, Sergei V

    2017-01-01

    Orientation by magnetic cues appears to be adaptive during animal migrations. Whereas the magnetic orientation in birds, mammals, and urodele amphibians is being investigated intensively, the data about anurans are still scarce. This study tests whether marsh frogs could determine migratory direction between the breeding pond and the wintering site by magnetic cues in the laboratory. Adult frogs (N = 32) were individually tested in the T-maze 127 cm long inside the three-axis Helmholtz coil system (diameter 3 m). The arms of the maze were positioned parallel to the natural migratory route of this population when measured in accordance with magnetic field. The frogs were tested under two-motivational conditions mediated by temperature/light regime: the breeding migratory state and the wintering state. The frogs' choice in a T-maze was evident only when analyzed in accordance with the direction of the magnetic field: they moved along the migratory route to the breeding pond and followed the reversion of the horizontal component of the magnetic field. This preference has been detected in both sexes only in the breeding migratory state. This suggests that adult ranid frogs can obtain directional information from the Earth's magnetic field as was shown earlier in urodeles and anuran larvae.

  20. Isoflurane anesthesia in the African clawed frog (Xenopus laevis).

    PubMed

    Smith, J M; Stump, K C

    2000-11-01

    Isoflurane is one of the safest and most accepted anesthetic agents for reptiles, birds, and mammals. It has also been used in terrestrial amphibians. The use of inhalation agents in an entirely aquatic frog presents a new dilemma for delivery in contrast to terrestrial species. The African Clawed Frog respires by using both transcutaneous gas exchange and air breathing. These frogs remain submerged for long periods of time, thus making standard inhalation techniques impractical. We tested five methods for delivering isoflurane: 1) bubbling isoflurane and oxygen in the water, 2) intracoelomic injection, 3) subcutaneous injection, 4) intramuscular injection, and 5) topical application. For the topical application, we developed a simple technique by using an absorptive pad with a vapor-barrier backing, saturating the pad with the liquid isoflurane, and placing the pad on the back of the frog while it was confined in a plastic bowl. Although two of the three injectable routes induced anesthesia, only the topical route produced rapid induction with consistent, safe recovery. Bubbling isoflurane with oxygen into water was unsuccessful. Topical application of isoflurane was most successful and appears to be a safe and practical method that can be used as an alternative to tricaine methylsulphonate, hypothermia, or other methods for anesthetizing African Clawed Frogs.

  1. Sophisticated Communication in the Brazilian Torrent Frog Hylodes japi

    PubMed Central

    de Sá, Fábio P.; Zina, Juliana; Haddad, Célio F. B.

    2016-01-01

    Intraspecific communication in frogs plays an important role in the recognition of conspecifics in general and of potential rivals or mates in particular and therefore with relevant consequences for pre-zygotic reproductive isolation. We investigate intraspecific communication in Hylodes japi, an endemic Brazilian torrent frog with territorial males and an elaborate courtship behavior. We describe its repertoire of acoustic signals as well as one of the most complex repertoires of visual displays known in anurans, including five new visual displays. Previously unknown in frogs, we also describe a bimodal inter-sexual communication system where the female stimulates the male to emit a courtship call. As another novelty for frogs, we show that in addition to choosing which limb to signal with, males choose which of their two vocal sacs will be used for visual signaling. We explain how and why this is accomplished. Control of inflation also provides additional evidence that vocal sac movement and color must be important for visual communication, even while producing sound. Through the current knowledge on visual signaling in Neotropical torrent frogs (i.e. hylodids), we discuss and highlight the behavioral diversity in the family Hylodidae. Our findings indicate that communication in species of Hylodes is undoubtedly more sophisticated than we expected and that visual communication in anurans is more widespread than previously thought. This is especially true in tropical regions, most likely due to the higher number of species and phylogenetic groups and/or to ecological factors, such as higher microhabitat diversity. PMID:26760304

  2. Litter mercury deposition in the Amazonian rainforest.

    PubMed

    Fostier, Anne Hélène; Melendez-Perez, José Javier; Richter, Larissa

    2015-11-01

    The objective of this work was to assess the flux of atmospheric mercury transferred to the soil of the Amazonian rainforest by litterfall. Calculations were based on a large survey of published and unpublished data on litterfall and Hg concentrations in litterfall samples from the Amazonian region. Litterfall based on 65 sites located in the Amazon rainforest averaged 8.15 ± 2.25 Mg ha(-1) y(-1). Average Hg concentrations were calculated from nine datasets for fresh tree leaves and ten datasets for litter, and a median concentration of 60.5 ng Hg g(-1) was considered for Hg deposition in litterfall, which averaged 49 ± 14 μg m(-2) yr(-1). This value was used to estimate that in the Amazonian rainforest, litterfall would be responsible for the annual removing of 268 ± 77 Mg of Hg, approximately 8% of the total atmospheric Hg deposition to land. The impact of the Amazon deforestation on the Hg biogeochemical cycle is also discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Abundance of pathogens in the gut and litter of broiler chickens as affected by bacitracin and litter management.

    PubMed

    Wei, Shan; Gutek, Amanda; Lilburn, Michael; Yu, Zhongtang

    2013-10-25

    Clostridium perfringens, Salmonella spp. and Campylobacter spp. are food-borne enteric pathogens that are commonly associated with poultry. The objective of this study was to investigate the effects of supplemental bacitracin and litter management (fresh vs. reused) on the abundance of these pathogens in commercial broiler chickens. Specific quantitative PCR (qPCR) assays were used to quantify C. perfringens, virulent C. perfringens that carried the genes encoding α-toxin (cpa) and NetB-toxin (netB), Salmonella, and Campylobacter in samples of ileal mucosa, cecal content, and litter. Campylobacter was not detected in any of the samples collected. The abundance of Salmonella was not affected by either bacitracin or litter condition. Generic C. perfringens was detected in the ileal mucosa at very low level at 10 days of age but was much higher at 35 days. Chickens reared on reused litter tended to have a lower abundance of generic C. perfringens compared with those reared on fresh litter. In the ileal mucosa, no cpa or netB was detected at day 10 but was detected at day 35 in the chickens that were not fed supplemental bacitracin. Chicks fed supplemental bacitracin had reduced abundance of generic C. perfringens as well as the cpa and netB genes in the ileal mucosa, cecal content, and litters. A strong positive correlation was found between the abundance of all three measurements of C. perfringens. The abundance of Salmonella spp. and C. perfringens was also shown to be correlated. This is the first study that has examined the effect of dietary bacitracin and litter conditions on the prevalence of these three common enteric pathogens. Unless contaminated from previous flocks, reused litter may not necessarily contain significantly greater abundances of C. perfringens or Salmonella.

  4. Evaluation of litter type and dietary coarse ground corn inclusion on broiler live performance, gastrointestinal tract development, and litter characteristics.

    PubMed

    Xu, Y; Stark, C R; Ferket, P R; Williams, C M; Nusairat, B; Brake, J

    2015-03-01

    Two 49 d floor pen studies were conducted to evaluate the effects of litter type and dietary coarse ground corn (CC) inclusion on broiler live performance, gastrointestinal tract (GIT) development, and litter characteristics. Experiment 1 was a 2×2 factorial arrangement of 2 genders (male or female) and 2 CC levels (0 or 50%). From 15 to 35 d, the addition of CC decreased feed intake (P<0.01) and BW gain (P<0.05) of males but not females. The inclusion of CC decreased feed intake (P<0.01) and BW gain (P<0.01) from 0 to 49 d but improved adjusted feed conversion ratio (AdjFCR) from 35 to 49 d (P<0.05). Male broilers exhibited better live performance than females during the study as evidenced by greater feed intake (P<0.01) and BW gain (P<0.01), and improved FCR (P<0.01), but with increased mortality (P<0.05). The inclusion of CC increased relative gizzard weight (P<0.01) and decreased relative proventriculus weight (P<0.01) at 49 d. Experiment 2 was a 2×2 factorial arrangement of 2 CC levels (0 or 50%) and 2 litter types (ground old litter or new wood shavings litter). The inclusion of CC decreased feed intake throughout the experiment without affecting final BW when only males were used and improved FCR after 25 d (P<0.01). New litter improved FCR from 1 to 14 d (P<0.01). At 49 d, the birds fed the CC diet had reduced excreta nitrogen (P<0.05) and litter moisture (P<0.05). In conclusion, 50% CC inclusion initially produced negative effects on live performance that became positive as BW increased. The effects of CC became evident at an earlier age for males. New litter had only a marginal benefit on broiler live performance.

  5. Influence of habitat, litter type, and soil invertebrates on leaf-litter decomposition in a fragmented Amazonian landscape.

    PubMed

    Vasconcelos, Heraldo L; Laurance, William F

    2005-07-01

    Amazonian forest fragments and second-growth forests often differ substantially from undisturbed forests in their microclimate, plant-species composition, and soil fauna. To determine if these changes could affect litter decomposition, we quantified the mass loss of two contrasting leaf-litter mixtures, in the presence or absence of soil macroinvertebrates, and in three forest habitats. Leaf-litter decomposition rates in second-growth forests (>10 years old) and in fragment edges (<100 m from the edge) did not differ from that in the forest interior (>250 m from the edges of primary forests). In all three habitats, experimental exclusion of soil invertebrates resulted in slower decomposition rates. Faunal-exclosure effects were stronger for litter of the primary forest, composed mostly of leaves of old-growth trees, than for litter of second-growth forests, which was dominated by leaves of successional species. The latter had a significantly lower initial concentration of N, higher C:N and lignin:N ratios, and decomposed at a slower rate than did litter from forest interiors. Our results indicate that land-cover changes in Amazonia affect decomposition mainly through changes in plant species composition, which in turn affect litter quality. Similar effects may occur on fragment edges, particularly on very disturbed edges, where successional trees become dominant. The drier microclimatic conditions in fragment edges and second-growth forests (>10 years old) did not appear to inhibit decomposition. Finally, although soil invertebrates play a key role in leaf-litter decomposition, we found no evidence that differences in the abundance, species richness, or species composition of invertebrates between disturbed and undisturbed forests significantly altered decomposition rates.

  6. Poultry litter and the environment: Physiochemical properties of litter and soil during successive flock rotations and after remote site deposition.

    PubMed

    Crippen, Tawni L; Sheffield, Cynthia L; Byrd, J Allen; Esquivel, Jesus F; Beier, Ross C; Yeater, Kathleen

    2016-05-15

    The U.S. broiler meat market has grown over the past 16 years and destinations for U.S. broiler meat exports expanded to over 150 countries. This market opportunity has spurred a corresponding increase in industrialized poultry production, which due to the confined space in which high numbers of animals are housed, risks accumulating nutrients and pollutants. The purpose of this research was to determine the level of pollutants within poultry litter and the underlying soil within a production facility; and to explore the impact of spent litter deposition into the environment. The study follows a production facility for the first 2.5 years of production. It monitors the effects of successive flocks and management practices on 15 physiochemical parameters: Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, moisture, Na, NO3(-)/N, organic matter, P, pH, S, and Zn. Litter samples were collected in-house, after clean-outs and during stockpiling. The soil before house placement, after the clean-outs and following litter stockpiling was monitored. Management practices markedly altered the physiochemical profiles of the litter in-house. A canonical discriminant analysis was used to describe the relationship between the parameters and sampling times. The litter profiles grouped into five clusters corresponding to time and management practices. The soil in-house exhibited mean increases in all physiochemical parameters (2-297 fold) except Fe, Mg, %M, and pH. The spent litter was followed after deposition onto a field for use as fertilizer. After 20 weeks, the soil beneath the litter exhibited increases in EC, Cu, K, Na, NO3(-)/N, %OM, P, S and Zn; while %M decreased. Understanding the impacts of industrialized poultry farms on the environment is vital as the cumulative ecological impact of this land usage could be substantial if not properly managed to reduce the risk of potential pollutant infiltration into the environment. Published by Elsevier B.V.

  7. Litter stoichiometric traits of plant species of high-latitude ecosystems show high responsiveness to global change without causing strong variation in litter decomposition.

    PubMed

    Aerts, R; van Bodegom, P M; Cornelissen, J H C

    2012-10-01

    • High-latitude ecosystems are important carbon accumulators, mainly as a result of low decomposition rates of litter and soil organic matter. We investigated whether global change impacts on litter decomposition rates are constrained by litter stoichiometry. • Thereto, we investigated the interspecific natural variation in litter stoichiometric traits (LSTs) in high-latitude ecosystems, and compared it with climate change-induced LST variation measured in the Meeting of Litters (MOL) experiment. This experiment includes leaf litters originating from 33 circumpolar and high-altitude global change experiments. Two-year decomposition rates of litters from these experiments were measured earlier in two common litter beds in sub-Arctic Sweden. • Response ratios of LSTs in plants of high-latitude ecosystems in the global change treatments showed a three-fold variation, and this was in the same range as the natural variation among species. However, response ratios of decomposition were about an order of magnitude lower than those of litter carbon/nitrogen ratios. • This implies that litter stoichiometry does not constrain the response of plant litter decomposition to global change. We suggest that responsiveness is rather constrained by the less responsive traits of the Plant Economics Spectrum of litter decomposability, such as lignin and dry matter content and specific leaf area.

  8. Species diversity and chemical properties of litter influence non-additive effects of litter mixtures on soil carbon and nitrogen cycling.

    PubMed

    Mao, Bing; Mao, Rong; Zeng, De-Hui

    2017-01-01

    Decomposition of litter mixtures generally cannot be predicted from the component species incubated in isolation. Therefore, such non-additive effects of litter mixing on soil C and N dynamics remain poorly understood in terrestrial ecosystems. In this study, litters of Mongolian pine and three dominant understory species and soil were collected from a Mongolian pine plantation in Northeast China. In order to examine the effects of mixed-species litter on soil microbial biomass N, soil net N mineralization and soil respiration, four single litter species and their mixtures consisting of all possible 2-, 3- and 4-species combinations were added to soils, respectively. In most instances, species mixing produced synergistic non-additive effects on soil microbial biomass N and soil respiration, but antagonistic non-additive effects on net N mineralization. Species composition rather than species richness explained the non-additive effects of species mixing on soil microbial biomass N and net N mineralization, due to the interspecific differences in litter chemical composition. Both litter species composition and richness explained non-additive soil respiration responses to mixed-species litter, while litter chemical diversity and chemical composition did not. Our study indicated that litter mixtures promoted soil microbial biomass N and soil respiration, and inhibited net N mineralization. Soil N related processes rather than soil respiration were partly explained by litter chemical composition and chemical diversity, highlighting the importance of functional diversity of litter on soil N cycling.

  9. Species diversity and chemical properties of litter influence non-additive effects of litter mixtures on soil carbon and nitrogen cycling

    PubMed Central

    Mao, Bing; Mao, Rong; Zeng, De-Hui

    2017-01-01

    Decomposition of litter mixtures generally cannot be predicted from the component species incubated in isolation. Therefore, such non-additive effects of litter mixing on soil C and N dynamics remain poorly understood in terrestrial ecosystems. In this study, litters of Mongolian pine and three dominant understory species and soil were collected from a Mongolian pine plantation in Northeast China. In order to examine the effects of mixed-species litter on soil microbial biomass N, soil net N mineralization and soil respiration, four single litter species and their mixtures consisting of all possible 2-, 3- and 4-species combinations were added to soils, respectively. In most instances, species mixing produced synergistic non-additive effects on soil microbial biomass N and soil respiration, but antagonistic non-additive effects on net N mineralization. Species composition rather than species richness explained the non-additive effects of species mixing on soil microbial biomass N and net N mineralization, due to the interspecific differences in litter chemical composition. Both litter species composition and richness explained non-additive soil respiration responses to mixed-species litter, while litter chemical diversity and chemical composition did not. Our study indicated that litter mixtures promoted soil microbial biomass N and soil respiration, and inhibited net N mineralization. Soil N related processes rather than soil respiration were partly explained by litter chemical composition and chemical diversity, highlighting the importance of functional diversity of litter on soil N cycling. PMID:28686660

  10. Plasma retinoids concentration in Leptodactylus chaquensis (Amphibia: Leptodactylidae) from rice agroecosystems, Santa Fe province, Argentina.

    PubMed

    Teglia, Carla M; Attademo, Andrés M; Peltzer, Paola M; Goicoechea, Héctor C; Lajmanovich, Rafael C

    2015-09-01

    Retinoids are known to regulate important processes such as differentiation, development, and embryogenesis of vertebrates: Alteration in endogenous retinoids concentration is linked with teratogenic effects. Retinol (ROH), retinoid acid (RA), and isoform 13-Cis-retinoic acid (13-Cis-RA), in plasma of a native adults frog, Leptodactylus chaquensis from a rice field (RF) and a forest (reference site; RS) were measured. ROH did not vary between treatment sites. RA and 13-Cis-RA activities were higher (93.7±8.6 μg mL(-1) and 131.7±11.4 μg mL(-1), respectively) in individuals collected from RF than in those from RS (65.5±8.6 μg mL(-1) and 92.2±10.2 μg mL(-1), respectively). The ratios retinoic acid-retinol (RA/ROH) and 13-Cis-RA/ROH revealed significantly higher values in RF than in RS. RA and 13-Cis-RA concentrations in plasma on wild amphibian's species such as L. chaquensis would be suitable biomarkers of pesticide exposure in field monitoring. Finally, the mechanism of alteration in retinoid metabolites alteration should be further explored both in larvae and adult, considering that the potential exposition and uptake contaminants vary between the double lives of these vertebrates.

  11. Development and characterization of 14 microsatellite markers for Buergeria japonica (Amphibia, Anura, Rhacophoridae).

    PubMed

    Komaki, Shohei; Igawa, Takeshi; Nozawa, Masafumi; Lin, Si-Min; Oumi, Shohei; Sumida, Masayuki

    2014-01-01

    Buergeria japonica is a common frog species distributed throughout almost all islands in Ryukyu Archipelago. Because of their exceptionally wide distribution and higher physiological tolerance comparing to the other anurans, their demographic history and formation of distribution are intrinsic topics in the herpetological fauna of Ryukyu. Microsatellite marker is ideal genetic marker for such studies at inter- and intra-population level. We therefore developed microsatellite markers of B. japonica utilizing Ion PGM™ sequencing. As a result of the screening, we developed a total of 14 polymorphic markers. To test availabilities of these markers, we genotyped four island populations. The total number of alleles and expected hetelozygosities per locus ranged from 4 to 21 and 0.00 to 0.864, respectively. The phylogenetic relationship among the four populations based on the genetic distances of these markers was congruent with general divergence pattern of amphibians and reptiles in Ryukyu area. These markers developed in this study are considered to be useful for future studies about phylogeography and demography of this species.

  12. Embryonic and larval development in the caecilian Ichthyophis kohtaoensis (Amphibia, gymnophiona): a staging table.

    PubMed

    Dünker, N; Wake, M H; Olson, W M

    2000-01-01

    Little is known about the developmental biology of caecilians-tropical, elongate, limbless, mostly fossorial amphibians that are members of the Order Gymnophiona. Ichthyophis kohtaoensis (Family Ichthyophiidae; southeast Asia) is an oviparous species in which maternal care of the clutch is provided. The clutch is laid in a burrow on land, and the embryos develop in their egg membranes, curved around a large yolk mass. Larvae are aquatic and exhibit characteristic features that are not present in the terrestrial adults. Because accurate descriptions of ontogenies and the establishment of standardized stages of embryonic and larval development are useful for both experimental and comparative embryology, a staging table for I.kohtaoensis was developed based on external morphological features. Development from the end of neurulation to metamorphosis was divided into 20 stages. Principal diagnostic features include development of the lateral line organs, formation of three pairs of external gills, development of the eyes, changes in yolk structure, changes in the structure of the cloacal aperture and growth of the tail, including the formation and regression of the tail fin. This study provides a comparison with descriptions of embryonic stages of I.glutinosus and Hypogeophis rostratus and with a recent staging table for the aquatic, viviparous caecilian Typhlonectes compressicauda, the only other caecilians for which reasonably complete ontogenetic information exists in the literature. Comparisons with established staging tables for selected frogs and salamanders are also presented.

  13. Vocal competition in male Xenopus laevis frogs

    PubMed Central

    Tobias, Martha L.; Corke, Anna; Korsh, Jeremy; Yin, David; Kelley, Darcy B.

    2011-01-01

    Male Xenopus laevis frogs produce underwater advertisement calls that attract gravid females and suppress calling by male competitors. Here we explore whether groups of males establish vocal ranks and whether auditory cues alone suffice for vocal suppression. Tests of male–male pairs within assigned groups reveal linear vocal dominance relations, in which each male has a defined rank. Both the duration over which males interact, as well as the number of competitive opportunities, affect linearity. Linear dominance across the group is stable for about 2 weeks; rank is dynamic. Males engage in physical interactions (clasping) while paired but clasping and vocal rank are not correlated. Playbacks of advertisement calls suppress calling and calls from high- and low-ranking males are equally effective. Thus, auditory cues alone suffice to suppress vocal behavior. Playback intensities equivalent to a nearby male advertising effectively suppress calling while low-intensity playbacks are either ineffective or stimulate vocal behavior. X. laevis advertisement calls are biphasic, composed of alternating fast and slow click trills. Approximately half the males tested are more vocally suppressed by all slow than by all fast trills; thus, these males can distinguish between the two phases. The fully aquatic family Pipidae diverged from terrestrial ancestors approximately 170 mya. Vocal suppression in the X. laevis mating system may represent the translation of an ancient anuran social strategy to underwater life. PMID:21442049

  14. Potassium selectivity of frog gastric luminal membrane.

    PubMed

    Kasbekar, D K

    1986-06-01

    Transmural potential difference (PD) and resistance (R) changes after luminal or serosal instillation of K+ were determined under various conditions in chambered preparations of frog gastric mucosae. Potassium selectivity of the luminal membrane is indicated by the rapid reversal of the inverted PD of mucosae bathed in NaCl-free, choline sulfate (Ch2SO4)-Ringer on the serosal side and unbuffered hypertonic Ch2SO4 solution on the luminal side on luminal K+ instillation. The delta PD responses are significantly attenuated, however, in histamine-stimulated mucosae bathed in hypotonic or in burimamide-inhibited mucosae bathed in hyper- and hypotonic luminal media, which suggests that the K+ selectivity of the luminal membrane resides largely in the tubular cell apical membrane. Imposing a serosal-to-luminal transmucosal K+ gradient in both histamine-stimulated and omeprazole-inhibited mucosae also reversed the normal orientation of PD but not in those inhibited with burimamide. In the latter, the PD inversion was attenuated but maintained its normal orientation. These data suggest that burimamide, but not omeprazole, acts by blocking luminal membrane K+ conductance. The inverted PD in mucosae bathed in Cl-free media may thus be due partially or fully to K+ diffusion driven by the cell-to-lumen K+ gradient via the luminal K+ conductance pathway. These findings have implications for the controversy surrounding the postulated electrogenicity of the gastric proton pump.

  15. Vocal competition in male Xenopus laevis frogs.

    PubMed

    Tobias, Martha L; Corke, Anna; Korsh, Jeremy; Yin, David; Kelley, Darcy B

    2010-11-01

    Male Xenopus laevis frogs produce underwater advertisement calls that attract gravid females and suppress calling by male competitors. Here we explore whether groups of males establish vocal ranks and whether auditory cues alone suffice for vocal suppression. Tests of male-male pairs within assigned groups reveal linear vocal dominance relations, in which each male has a defined rank. Both the duration over which males interact, as well as the number of competitive opportunities, affect linearity. Linear dominance across the group is stable for about 2 weeks; rank is dynamic. Males engage in physical interactions (clasping) while paired but clasping and vocal rank are not correlated. Playbacks of advertisement calls suppress calling and calls from high- and low-ranking males are equally effective. Thus, auditory cues alone suffice to suppress vocal behavior. Playback intensities equivalent to a nearby male advertising effectively suppress calling while low-intensity playbacks are either ineffective or stimulate vocal behavior. X. laevis advertisement calls are biphasic, composed of alternating fast and slow click trills. Approximately half the males tested are more vocally suppressed by all slow than by all fast trills; thus, these males can distinguish between the two phases. The fully aquatic family Pipidae diverged from terrestrial ancestors approximately 170 mya. Vocal suppression in the X. laevis mating system may represent the translation of an ancient anuran social strategy to underwater life.

  16. Huge populations and old species of Costa Rican and Panamanian dirt frogs inferred from mitochondrial and nuclear gene sequences.

    PubMed

    Crawford, A J

    2003-10-01

    Molecular genetic data were used to investigate population sizes and ages of Eleutherodactylus (Anura: Leptodactylidae), a species-rich group of small leaf-litter frogs endemic to Central America. Population genetic structure and divergence was investigated for four closely related species surveyed across nine localities in Costa Rica and Panama. DNA sequence data were collected from a mitochondrial gene (ND2) and a nuclear gene (c-myc). Phylogenetic analyses yielded concordant results between loci, with reciprocal monophyly of mitochondrial DNA haplotypes for all species and of c-myc haplotypes for three of the four species. Estimates of genetic differentiation among populations (FST) based upon mitochondrial data were always higher than nuclear-based FST estimates, even after correcting for the expected fourfold lower effective population size (Ne) of the mitochondrial genome. Comparing within-population variation and the relative mutation rates of the two genes revealed that the Ne of the mitochondrial genome was 15-fold lower than the estimate of the nuclear genome based on c-myc. Nuclear FST estimates were approximately 0 for the most proximal pairs of populations, but ranged from 0.5 to 1.0 for all other pairs, even within the same nominal species. The nuclear locus yielded estimates of Ne within localities on the order of 105. This value is two to three orders of magnitude larger than any previous Ne estimate from frogs, but is nonetheless consistent with published demographic data. Applying a molecular clock model suggested that morphologically indistinguishable populations within one species may be 107 years old. These results demonstrate that even a geologically young and dynamic region of the tropics can support very old lineages that harbour great levels of genetic diversity within populations. The association of high nucleotide diversity within populations, large divergence between populations, and high species diversity is also discussed in light of

  17. Sticking under wet conditions: the remarkable attachment abilities of the torrent frog, Staurois guttatus.

    PubMed

    Endlein, Thomas; Barnes, W Jon P; Samuel, Diana S; Crawford, Niall A; Biaw, Ang Bee; Grafe, Ulmar

    2013-01-01

    Tree frogs climb smooth surfaces utilising capillary forces arising from an air-fluid interface around their toe pads, whereas torrent frogs are able to climb in wet environments near waterfalls where the integrity of the meniscus is at risk. This study compares the adhesive capabilities of a torrent frog to a tree frog, investigating possible adaptations for adhesion under wet conditions. We challenged both frog species to cling to a platform which could be tilted from the horizontal to an upside-down orientation, testing the frogs on different levels of roughness and water flow. On dry, smooth surfaces, both frog species stayed attached to overhanging slopes equally well. In contrast, under both low and high flow rate conditions, the torrent frogs performed significantly better, even adhering under conditions where their toe pads were submerged in water, abolishing the meniscus that underlies capillarity. Using a transparent platform where areas of contact are illuminated, we measured the contact area of frogs during platform rotation under dry conditions. Both frog species not only used the contact area of their pads to adhere, but also large parts of their belly and thigh skin. In the tree frogs, the belly and thighs often detached on steeper slopes, whereas the torrent frogs increased the use of these areas as the slope angle increased. Probing small areas of the different skin parts with a force transducer revealed that forces declined significantly in wet conditions, with only minor differences between the frog species. The superior abilities of the torrent frogs were thus due to the large contact area they used on steep, overhanging surfaces. SEM images revealed slightly elongated cells in the periphery of the toe pads in the torrent frogs, with straightened channels in between them which could facilitate drainage of excess fluid underneath the pad.

  18. Sticking under Wet Conditions: The Remarkable Attachment Abilities of the Torrent Frog, Staurois guttatus

    PubMed Central

    Endlein, Thomas; Barnes, W. Jon P.; Samuel, Diana S.; Crawford, Niall A.; Biaw, Ang Bee; Grafe, Ulmar

    2013-01-01

    Tree frogs climb smooth surfaces utilising capillary forces arising from an air-fluid interface around their toe pads, whereas torrent frogs are able to climb in wet environments near waterfalls where the integrity of the meniscus is at risk. This study compares the adhesive capabilities of a torrent frog to a tree frog, investigating possible adaptations for adhesion under wet conditions. We challenged both frog species to cling to a platform which could be tilted from the horizontal to an upside-down orientation, testing the frogs on different levels of roughness and water flow. On dry, smooth surfaces, both frog species stayed attached to overhanging slopes equally well. In contrast, under both low and high flow rate conditions, the torrent frogs performed significantly better, even adhering under conditions where their toe pads were submerged in water, abolishing the meniscus that underlies capillarity. Using a transparent platform where areas of contact are illuminated, we measured the contact area of frogs during platform rotation under dry conditions. Both frog species not only used the contact area of their pads to adhere, but also large parts of their belly and thigh skin. In the tree frogs, the belly and thighs often detached on steeper slopes, whereas the torrent frogs increased the use of these areas as the slope angle increased. Probing small areas of the different skin parts with a force transducer revealed that forces declined significantly in wet conditions, with only minor differences between the frog species. The superior abilities of the torrent frogs were thus due to the large contact area they used on steep, overhanging surfaces. SEM images revealed slightly elongated cells in the periphery of the toe pads in the torrent frogs, with straightened channels in between them which could facilitate drainage of excess fluid underneath the pad. PMID:24086297

  19. Prevalence of Batrachochytrium dendrobatidis in three species of wild frogs on Prince Edward Island, Canada.

    PubMed

    Forzán, M J; Vanderstichel, R; Hogan, N S; Teather, K; Wood, J

    2010-09-02

    Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has resulted in the decline or extinction of approximately 200 frog species worldwide. It has been reported throughout much of North America, but its presence on Prince Edward Island (PEI), on the eastern coast of Canada, was unknown. To determine the presence and prevalence of Bd on PEI, skin swabs were collected from 115 frogs from 18 separate sites across the province during the summer of 2009. The swabs were tested through single round end-point PCR for the presence of Bd DNA. Thirty-one frogs were positive, including 25/93 (27%) green frogs Lithobates (Rana) clamitans, 5/20 (25%) northern leopard frogs L. (R.) pipiens, and 1/2 (50%) wood frogs L. sylvaticus (formerly R. sylvatica); 12 of the 18 (67%) sites had at least 1 positive frog. The overall prevalence of Bd infection was estimated at 26.9% (7.2-46.7%, 95% CI). Prevalence amongst green frogs and leopard frogs was similar, but green frogs had a stronger PCR signal when compared to leopard frogs, regardless of age (p < 0.001) and body length (p = 0.476). Amongst green frogs, juveniles were more frequently positive than adults (p = 0.001). Green frogs may be the most reliable species to sample when looking for Bd in eastern North America. The 1 wood frog positive for Bd was found dead from chytridiomycosis; none of the other frogs that were positive for Bd by PCR showed any obvious signs of illness. Further monitoring will be required to determine what effect Bd infection has on amphibian population health on PEI.

  20. Prevalence and intensity of Alaria alata (Goeze, 1792) in water frogs and brown frogs in natural conditions.

    PubMed

    Patrelle, Cécile; Portier, Julien; Jouet, Damien; Delorme, Daniel; Ferté, Hubert

    2015-12-01

    In the last 15 years, the mesocercariae of Alaria alata have frequently been reported in the wild boar during routine Trichinella inspections made compulsory for the trade of venison meat in Europe. If these studies have focused primarily on mesocercariae isolated from meat, few works have been done so far to understand the circulation of the parasite in natural conditions especially in the intermediate hosts. This study focuses on the second intermediate hosts of this parasite assessing the suitability of two amphibian groups-brown frogs and water frogs sensu lato-for mesocercarial infection on an area where A. alata has already been identified in water snails and wild boars. During this study, both groups showed to be suitable for mesocercarial infection, with high prevalence and parasite burdens. Prevalence was higher in the brown frog group (56.9 versus 11.54 % for water frogs) which would indicate that it is a preferential group for infection on the study area, though reasons for this remain to be investigated. No significant difference among prevalences was observed between tadpoles and frogs. This study, the first focusing on A. alata in these amphibians in Europe, provides further information on circulation of this parasite in natura.