Cadmium accumulation in the crayfish, Procambarus clarkii, using graphite furnace atomic absorption spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Diaz-Mayans, J.; Hernandez, F.; Medina, J.; Del Ramo, J.; Torreblanca, A.

1986-11-01

Lake Albufera and the surrounding rice-field waters are being subject to very heavy loads of sewage and toxic industrial residues (including heavy metals and pesticides) from the many urban and wastewaters in this area. The American red crayfish Procambarus clarkii is native to the Louisiana marshes (USA). In 1978, the crayfish appeared in Lake Albufera near Valencia (Spain), and presently, without adequate sanitary controls, the crayfish is being fished commercially for human consumption. In view of this interest, it is important to have accurate information on concentrations of cadmium in natural waters and cadmium levels of tissues of freshwaters animals used as human food, as well as the accumulation rates of this metal in this animal. In the present study, the authors investigated the accumulation of cadmium in several tissues of the red crayfish, P clarkii (Girard) from Lake Albufera following cadmium exposure. Determinations of cadmium were made by flameless atomic absorption spectroscopy and the standard additions method. Digestion of samples was made by wet ashing in open flasks with concentrated HNO/sub 3/ at 80-90/sup 0/C.

Distribution of native and exotic branchiobdellidans (Annelida: Clitellata on their respective crayfish hosts in northern Italy, with the first record of native Branchiobdella species on an exotic North American crayfish.

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Joy N. RAYBURN

1999-02-01

Full Text Available Branchiobdellidans were found on crayfish at the 18 sites examined in northern Italy. At 15 of the sites the native crayfish, Austropotamobius pallipes, was collected and all supported specimens of Branchiobdella italica. A few specimens of B. parasita were found at only two of these sites and no specimens of B. hexodonta were observed during the survey. The North American Louisiana red swamp crayfish, Procambarus (Scapulicambarus clarkii has been found in three additional sites around Carmagnola, south of Torino. The exotic Cambarincola mesochoreus was recovered from red crayfish at two sites. However, no specimens of C. mesochoreus were found at the third site, but specimens B. italica and B. parasita were identified. This is the first record of native Branchiobdella spp. on an exotic and wild crayfish in northern Italy.

Effects of temperature on the acute toxicity of heavy metals (Cr, Cd, and Hg) to the freshwater crayfish, Procambarus clarkii (Girard)

Energy Technology Data Exchange (ETDEWEB)

Del Ramo, J.; Diaz-Mayans, J.; Torreblanca, A.; Nunez, A.

1987-05-01

Chromium, an essential trace element for humans and animals is involved in normal carbohydrate metabolism; however, it is toxic at high concentrations. There is no evidence that cadmium and mercury are biologically essential but their toxicity for organisms is well known. Both cause toxic effects at low concentrations to most organisms, especially in combination with other environmental variables such as temperature. Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues (including heavy metals) from the many urban and waste waters in this area. In 1978, the American red crayfish Procambarus clarkii appeared in lake Albufera and in the surrounding rice fields. Without adequate sanitary control, the crayfish is presently being fished commercially for human consumption. The purpose of the present study is to evaluate the degree of toxicity of various heavy metals (chromium, cadmium and mercury) to freshwater crayfish Procambarus clarkii at various temperatures.

Food preference and feeding rhythm in red swamp crayfish Procambarus clarkii%克氏原螯虾的食物选择性及其摄食节律

Institute of Scientific and Technical Information of China (English)

徐增洪; 周鑫; 水燕

2012-01-01

Juvenile and adult red swamp crayfish (Procambarus clarkii) were reared in tanks (60 cm × 40 cm × 40 cm) at a rate of 20 individuals per tank and fed 5 aquatic plant species (Altemanthera philoxeroides, Eichhornia crassipes, Lesser duckweed Lemna minor, Elodea nultallii, and pondweed ValUsneria natans) to evaluate food I-tems and changes in food filling in stomach and intestines during day and night. In addition, the growth was compared in th crayfish reared in a paddyfield and fed three diets ( crayfish feedstuff with 30% protein, aquatic grasses and trash fish). The food in the intestine of the juvenile crayfish was found to be primarily comprised of zooplankton and phytoplankton. The adult crayfish was shown to have lower food preference, almost all of edible aquatic animals and plants, organic detritus, and artificial feed available in waters being consumed, and aquatic plants constituting their main food due to wide distribution, and easy ingesting. The feeding rhythm was observed during day and night in the crayfish culture pond, the two peaks at 8:00-10:00 and 19:00-22:00. There was significantly better growth in the adult crayfish fed Elodea nuttallii, Lesser duckweed and Vallisneria natans than that in the crayfish fed Altemanthera philoxeroides and Eichharnia crassipes(P0. 05) , even though the crayfish fed Lesser duckweed had slightly better growth than the crayfish fed Elodea nuUallii, and ValUsneria natans did. There was significant difference in daily weight gain rate in the juvenile crayfish fed lesser duckweed, Elodea nuttallii, Vallisneria natans, Altemanthera philoxeroides,Eichhornia crassipes(P<0.05). In the rice field, however, the crayfish fed trash fish was shown to have much better growth than that the crayfish fed pelleted food, and pelleted feedstuff combined with aquatic plants.%对克氏原螫虾Procambarus clarkii幼虾和成虾的胃及肠道内的食物组成和食物充塞度的昼夜变化规律进行了观察；在水族箱(60 cm

Accelerated hatching of southern leopard frog (Rana sphenocephala) eggs in response to the presence of a crayfish Procambarus nigrocinctus predator

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Daniel Saenz; James B. Johnson; Cory K. Adams; Gage H. Dayton

2003-01-01

Phenotypic plasticity, such as morphological and behavioral changes in response to predators, is common in larval anurans. Less is known about inducible defenses in the embryonic stages of development. We investigated the predation risk imposed by crayfish (Procambarus nigrocinctus) on southern leopard frog (Rana sphenocephala)...

CRAYFISH PREDATION ON TADPOLES : A COMPARISON BETWEEN A NATIVE (AUSTROPOTAMOBIUS PALLIPES AND AN ALIEN SPECIES (PROCAMBARUS CLARKII.

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GHERARDI F.

2001-04-01

Full Text Available In the laboratory, the motivation and/or ability to prey on anuran larvae (Bufo bufo, Rana kl. esculenta and R. italica were compared between a native European (Austropotamobius pallipes and an alien North American crayfish species (Procambarus clarkii. Both were skilled predators of tadpoles, adopting a sit-and-wait strategy. However, because P. clarkii displayed lower latency times in the presence of one of the three amphibians (Rana kl. esculenta here tested, the hypothesis is raised that invasive crayfish are more opportunistic predators and possibly faster in switching to different prey than those species they are displacing. From a conservation perspective, these preliminary results further emphasise the importance of studies centred on the invasion-displacement dichotomy.

Oxygen uptake by excised gills of Procambarus clarkii (Girard) from Albufera Lake of Valencia, Spain, under heavy metal treatments

Energy Technology Data Exchange (ETDEWEB)

Diaz-Mayans, J.; Torreblanca, A.; Del Ramo, J.; Nunez, A.

1986-06-01

The American red crayfish Procambarus clarkii, originally from Louisiana (USA) was introduced in Spain in the 70's in the Guadalquivir River swamps. It appeared first randomly and in a more regular basis afterwards since 1978 in the Albufera Lake south of Valencia and in the surrounding rice fields. Albufera lake and surrounding rice fields waters are being subject since the last three decades to very heavy load of sewage, toxic industrial residues including heavy metals and pesticides from the many urban and industrial settlements in the zone. In the present study, the authors have investigated the effect that heavy metals (Chromium, Cadmium and Mercury) have on the oxygen uptake by excised bills of Procambarus clarkii (Girard) coming from the Albufera Lake (Valencia).

Heavy metals bioaccumulation in selected tissues of red swamp crayfish: An easy tool for monitoring environmental contamination levels.

Science.gov (United States)

Goretti, E; Pallottini, M; Ricciarini, M I; Selvaggi, R; Cappelletti, D

2016-07-15

In this paper we explored the heavy metal bioaccumulation (Cd, Cu, Pb and Zn) in Procambarus clarkii, a crayfish recently suggested as a potential bioindicator for metals pollution in freshwater systems. The present study is focused on crayfishes populations caught in a heavily polluted industrial and in a reference sites (Central Italy), though the results are generalized with a thorough analysis of literature metadata. In agreement with the literature, the hepatopancreas (Hep, detoxification tissues) of the red swamp crayfish showed a higher concentration of heavy metals in comparison to the abdominal muscle (AbM, not detoxification tissues) in the sites under scrutiny. Hep/AbM concentration ratio was dependent on the specific metal investigated and on its sediment contamination level. Specifically we found that Hep/AbM ratio decreases as follows: Cd (11.7)>Cu (5.5)>Pb (3.6)>Zn (1.0) and Pb (4.34)>Cd (3.66)>Zn (1.69)>Cu (0.87) for the industrial and reference sites, respectively. The analysis of our bioaccumulation data as well as of literature metadata allowed to elaborate a specific contamination index (Toxic Contamination Index, TCI), dependent only on the bioaccumulation data of hepatopancreas and abdominal muscle. In the industrial site, TCI expressed values much higher than the unit for Cd and Cu, confirming that these metals were the main contaminants; in contrast for lower levels of heavy metals, as those observed in the reference site for Cu, Zn and Pb, the index provided values below unit. TCI is proposed as a useful and easy tool to assess the toxicity level of contaminated sites by heavy metals in the environmental management. Copyright © 2016. Published by Elsevier B.V.

Determination of mercury by cold-vapor technique in several tissues of treated American red crayfish (Procambarus clarkii)

Energy Technology Data Exchange (ETDEWEB)

Del Ramo, J.; Pastor, A.; Diaz-Mayans, J.; Medina, J.; Torreblanca, A.

1988-01-01

Adult intermolt specimens of American red crayfish (Procambarus clarkii) collected from Lake Albufera (Valencia, Spain), were exposed to mercury during 96 h. The Hg-concentrations used were 50, 100, and 250 ..mu..g Hg/l as Cl/sub 2/Hg. The content of mercury in muscle, midgut gland, antennal glands and gills was investigated. Determinations of mercury were made by cold-vapor technique and AAS. The mercury levels in all examined tissues increased significantly with increasing Hg-concentration in the water.

Invasive crayfish in the Pacific Northwest

Science.gov (United States)

Pearl, Christopher A.; McCreary, Brome; Adams, Michael

2011-01-01

Invasive species directly threaten freshwater biodiversity, particularly in regions of high aquatic richness like the Pacific Northwest (PNW). Crayfish are among the most impactful of aquatic invasive species. Invasive crayfish are considered ecosystem engineers due to their ability to alter basic wetland properties, such as reducing vegetation and bank integrity and increasing turbidity. In areas where invasion is advanced, crayfish pose major economic and ecological problems. Crayfish have been widely introduced for aquaculture and can become established in a wide range of habitat conditions. They also may be spread by anglers who use them as bait. Several non-native crayfish are established in the PNW, but the extent of their invasion is not well known. At least two groups are known from scattered sites in the PNW, and both have proven problematic for native species in other parts of the world: Red swamp crayfish (Procambarus clarkii) and several members of the genus Orconectes. Both groups are native to areas of the eastern United States. Both are identified globally as invasives of high concern and appear on the Oregon Department of Fish and Wildlife's "10 Most Unwanted" and the U.S. Forest Service's "Primary Species of Concern" lists for stream systems in the PNW. Despite the presence of introduced crayfish in the PNW and their high potential for negative effects, the scope of their invasion and effects on aquatic systems are not well known. The U.S. Geological Survey (USGS), along with local groups and state agencies, is working to clarify crayfish distribution and to outline which basins may not yet be invaded. Other goals are to improve understanding of habitat associations of invasive crayfish and their potential effects on native crayfish.

Effects of cadmium on the biochemical composition of the freshwater crayfish Procambarus clarkii (Girard, 1852)

Energy Technology Data Exchange (ETDEWEB)

Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

1991-12-01

Lake Albufera of Valencia (Spain) and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic residues. Among these residues include heavy metals which have been deposited from the many urban and waste waters in this area. The American red crayfish, Procambarus clarkii from Albufera Lake has high resistance to heavy metals. The authors have also found that P. clarkii shows a high capacity for cadmium accumulation in experimental conditions and natural conditions since crayfish collected in this area contained considerable amounts of cadmium in several tissues even after 15 days of depuration in clean water. Since the physiological changes that take place when organisms are exposed to sublethal levels of stress could include rate of feeding as well as respiration and excretion, the net result could be a change in energy available for growth and reproduction. In this work, the authors have studied the biochemical energy composition of hepatopancreas, muscle and gills of P. clarkii after short term sublethal exposure to cadmium.

Red swamp crayfish: biology, ecology and invasion - an overview

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Tainã Gonçalves Loureiro

Full Text Available ABSTRACTAlien species have been transported and traded by humans for many centuries. However, with the era of globalization, biological invasions have reached notable magnitudes. Currently, introduction of alien species is one of the major threats to biodiversity and ecosystem functioning. The North American crayfish Procambarus clarkii is one of the most widely introduced freshwater species in the world, especially due to its high economic importance. It is responsible for great modifications in invaded environments causing irreparable ecological and economic damages. Its impressive ability to successfully colonize a wide range of environments is a consequence of its behavioural and biological characteristics that can adapt to features of the invaded location, conferring to this species a notable ecological plasticity. This review summarizes the available information regarding P. clarkii's biology and invasive dynamics around the world in order to contribute to the understanding of the threats posed by its establishment, as well as to support management and impact mitigation efforts.

A review of the ever increasing threat to European crayfish from non-indigenous crayfish species

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D.M. Holdich

2009-01-01

Full Text Available Non-indigenous crayfish species (NICS in Europe now outnumber indigenous crayfish species (ICS 2:1, and it has been predicted that they may dominate completely in the next few decades unless something is done to protect them. Of the ten NICS introduced at least nine have become established in areas occupied by four of the five ICS. A decline in stocks of ICS has been recorded in many countries in the face of increasing populations of NICS. Most European countries retain at least one ICS but all are under threat from habitat loss, deteriorating water quality, overfishing, climate change, and most importantly from NICS and crayfish plague. The threat to ICS is so great in some countries that “ark”sanctuary sites are being established.The three most widely-spread NICS are the North American species: Pacifastacus leniusculus, Orconectes limosus and Procambarus clarkii. These can be considered as “Old NICS”, which were introduced before 1975, compared with the “New NICS”, which were introduced after 1980, such as the North American species: Orconectes immunis, Orconectes juvenilis, Orconectes virilis, Procambarus sp. and Procambarus acutus; and the Australian species: Cherax destructor and Cherax quadricarinatus, all of which have much narrower ranges in Europe. The North American species are potentially capable of acting as vectors of crayfish plague. Outbreaks of this disease occur regularly where there are high concentrations of vectors.In addition to the NICS currently established in the wild, a further threat exists through the aquarium trade, where many American and Australian species are available via the internet and in aquarist centres. Owners of such species may discard them into the freshwater environment when they grow too big as with some Cherax spp. and Orconectes spp., or multiply too frequently as with Procambarus sp. (a parthenogenetic species. A conceptual model is presented as a possible way forward for protecting the

INTERACTION BETWEEN NATIVE AND ALIEN SPECIES OF CRAYFISH IN AUSTRIA: CASE STUDIES

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PÖCKL M.

2002-07-01

Full Text Available In Austria, three indigenous crayfish species occur: the noble crayfish (Astacus astacus, the stone crayfish (Austropotamobius torrentium, and the white-clawed crayfish (Austropotamobius pallipes. It is not known if Astacus leptodactylus is autochthonous in the very eastern part of Austria, near the border with Hungary and Slovakia. In other parts of Austria the Turkish crayfish has been transplanted into several gravel pits and ponds. Up to now, the red swamp crayfish (Procambarus clarkii is not known to occur in the wild, but can be bought alive in fish markets, restaurants, and the aquarium trade. The Nearctic spiny-cheek crayfish (Orconectes limosus and the signal crayfish (Pacifastacus leniusculus have been introduced since the 1970s by crayfish farmers because these species are resistant to the crayfish plague fungus (Aphanomyces astaci. There are just a few populations of O. limosus, and the species is not spreading actively. However, P. leniusculus is widespread all over Austria, and was illegally introduced from one water body to another. It can be characterized as an aggressive, invasive North American species, spreading actively and acting as a vector of the crayfish plague. Unfortunately the habitat requirements of the native noble crayfish and the alien signal crayfish are nearly the same. Case studies are given in the following chapters: the first group of examples refers to water bodies where the alien signal crayfish is most probably the cause of displacement of the indigenous noble crayfish: 1 Hintersee, 2 Irrsee (« Zeller See », 3 north-western Lower Austria (« Waldviertel », 4 Merzenstein (aquacultural enterprise, 5 Neufelder See. The second group of examples refers to water bodies where alien and indigenous species are able to coexist: a the confluence of the main course of the Danube River, the Ölhafen and the Neue Donau in the southeast part of Vienna, b the Schönauer Wasser, a backwater of the Danube River downstream

GLUTATHIONE AND ANTIOXIDANT ENZYMES IN THE HEPATOPANCREAS OF CRAYFISH PROCAMBARUS CLARKII (GIRARD, 1852 OF LAKE TRASIMENO (ITALY

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ELIA A. C.

2006-01-01

Full Text Available Antioxidant parameters, such as total glutathione, glutathione S-transferase, glutathione peroxidase, glutathione reductase, glyoxalases, catalase, and some heavy metals such as, lead, cadmium and chromium were examined in hepatopancreas of both sexes of Procambarus clarkii collected seasonally from Lake Trasimeno, from winter 2002-2003 to autumn 2003. Heavy metals content in hepatopancreas in males and females of P. clarkii was low and did not vary through the sampling periods and between sexes. On the contrary, crayfish exhibited sex-dependent differences in levels of some enzyme activities and of total glutathione, and no apparent relationship was found between contaminant burdens and antioxidant indexes in hepatopancreas. Because measured metal concentrations were low, other factors, presumably, were involved in antioxidant variations in P. clarkii and these latter seemed to be affected more by biological and environmental factors, other than those related to pollutants body burdens.

The future of the indigenous freshwater crayfish Austropotamobius italicus in Basque Country streams: Is it possible to survive being an inconvenient species?

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L. García-Arberas

2009-01-01

Full Text Available The white-clawed freshwater crayfish Austropotamobius italicus is listed as “vulnerable” in the Spanish Red List of threatened species, but local legislation varies among Spanish regions. Thus, while in some places the species is classified as “in risk of extinction” and various plans of conservation and restoration have been implemented, in the Basque Country and other regions the species is not listed. The distribution of the white-clawed crayfish in the province of Biscay (Basque Country was studied from 1993 to 2007 at more than 600 sampling locations. Results show that 108 streams were inhabited by the native crayfish species A. italicus while 137 streams were inhabited by non-native signal crayfish Pacifastacus leniusculus or red-swamp crayfish Procambarus clarkii. The spread of non-native crayfish is not the only threat to the native species whose survival is also closely dependent on how watersheds are managed. Most A. italicus populations inhabit headwaters, where forestry activities are very important. The presence of native crayfish in heavily forested areas results in a conflict of interests and makes its conservation particularly difficult. We employed a SWOT analysis – an assessment and decision tool commonly used in marketing and business – to evaluate the situation of the native white-clawed crayfish in Biscay, a province characterized by very high demographic pressure. SWOT analysis has proved to be a useful diagnostic tool and can help develop better and more accurate management strategies for the conservation of native crayfish threatened by multiple stressors.

Comparing macrophyte herbivory by introduced Louisiana crayfish ...

African Journals Online (AJOL)

The omnivorous Louisiana crayfish, Procambarus clarkii, has caused significant changes to macrophyte communities worldwide and may have similar negative effects in Kenya if used as a biological control agent for snails harbouring human schistosomes. Here we examine how herbivory by the introduced Louisiana ...

HERITABILITY AND RESPONSE TO SELECTION FOR GROWTH IN THE F1 GENERATION OF CRAYFISH Procambarus acanthophorus

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Carlos Perez Rostro

2012-11-01

Full Text Available The crayfish Procambarus (A. acanthophorus is a crustacean relevant for regional fisheries in Veracruz, Mexico, with ideal aquaculture characteristics, except for its small size. Thus, a study was conducted with the aim to evaluate the response to selection in the first generation (F1 and heritability (h2 of the crayfish. A group of 2135 organisms with average weight (±S.D. 4.1 ± 1.79 g were captured from the wild (G0, and 10 % (i = 1,755 of the population was selected with the highest body weight by gender: 140 females (5.62 ± 1.97 g and 48 males (6.02 ± 1.9 g, forming the progenitors of the selection line (LS. The control line (LC was formed from a batch obtained at random. Thirty full-sib families were obtained per line (F1, and cultured individually for five months in a recirculation system with mechanical and biological filtration under laboratory conditions and supplied with food twice a day (Camaronina 35 % protein. Monthly heritability (h2 in broad sense was estimated using a full-sib design, based on the components of variance (ANOVA REML method and the growth was compared between lines in the F1. The mean h2's for weight after five months of culture were 0.27±0.11 for LC and 0.34±0.12 for LS, being the LS in F1 9.6 % heavier than the LC, with 84 and 88 % survival at the end of the study. It is possible to implement a breeding program based on selection for species growth.

Identification of exotic North American crayfish in Europe by DNA barcoding

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Filipová L.

2011-05-01

Full Text Available Several alien crayfish of North American origin have become established in Europe in recent decades, but their identification is often confusing. Our aim was to verify the taxonomic status of their European populations by DNA barcoding. We sequenced the cytochrome c oxidase subunit I (COI gene fragment of individuals representing all American crayfish known from European waters, and compared the results with reference sequences from North America. Our results confirm the morphological identification of Orconectes juvenilis from a population in eastern France, and of the marbled crayfish (Marmorkrebs, i.e., a parthenogenetic form of Procambarus fallax, from south-western Germany. Sequences of most individuals of presumed Procambarus acutus from the Netherlands were similar to American P. cf. acutus, but one was divergent, closer to a sequence of a reference individual of P. cf. zonangulus. However, divergences among three American P. cf. zonangulus samples were also high, comparable to interspecific variation within cambarid species complexes. The divergence between O. immunis from Europe and America also reached values corresponding to those observed among distinct Orconectes species. Genetic variation in the American range of these crayfish should therefore be further studied. Our study shows that DNA barcoding is useful for the rapid and accurate identification of exotic crayfish in Europe, and also provides insights into overall variation within these taxa.

Potential impacts of alien freshwater crayfish in South Africa | de ...

African Journals Online (AJOL)

The habitat preferences and life history characteristics of four alien species of freshwater crayfish (Cherax tenuimanus, C. destructor, C. quadricarinatus and Procambarus clarkii) are reviewed. The potential impact of these species on South African freshwater ecosystems is assessed and the desirability of allowing their ...

Fatty acids and astaxanthin composition of two edible native Mexican crayfish Cambarellus (C.) montezumae and Procambarus (M.) bouvieri

International Nuclear Information System (INIS)

Coral-Hinostroza, G.; Diaz-Martinez, M.; Huberman, A.; Silencio-Barrita, J.L.

2016-01-01

The content and composition of the fatty acids (F As) and astaxanthin (AST) in the edible forms of crayfish: the whole animal of Cambarellus (C.) montezumae, and the tail meat (TM) of Procambarus (M.) bouvieri were determined by GC and HPLC. The exoskeleton (EXK) of P. (M.) bouvieri was also studied. Unsaturated FAs, and mostly oleic acid (C18:1 n-9), were predominant in both edible forms. The contents of the polyunsaturated eicosapentaenoic (C20:5 n-3, EPA), arachidonic (C20:4 n-6, ARA) and docosahexaenoic acid (C22:6 n-3, DHA), were higher in the TM of P. (M.) bouvieri than in the complete C. (C.) montezumae (p 79.50%). AST esters were enriched with saturated FAs in C. (C.) montezumae and with PUFAs in EXK of P. (M.) bouvieri. We conclude that both C. (C.) montezumae and the TM of P. (M.) bouvieri are traditional foods rich in n-3 PUFAs and C. (C.) montezumae in AST. The EXK of P. (M.) bouvieri is a rich potential source of AST, n-3 PUFAs, and the combination AST-DHA. [es

Visual shape recognition in crayfish as revealed by habituation.

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Cinzia Chiandetti

2017-08-01

Full Text Available To cope with the everyday challenges that they encounter in their evolutionary niche, crayfish are considered to rely mainly on chemical information or, alternatively, on tactile information, but not much on vision. Hence, research has focused on chemical communication, whereas crayfish visual abilities remain poorly understood and investigated. To fill in this gap, we tested whether crayfish (Procambarus clarkii can distinguish between two different visual shapes matched in terms of luminance. To this aim, we measured both the habituation response to a repeated presentation of a given shape, a downright Y, and the response recovery when a novel shape was presented. The novel shape could be either a Möbius or the same Y-shape but upright rotated. Our results demonstrate that, after habituation to the downright Y, crayfish showed a significantly higher response recovery to the Möbius as compared to the upright rotated Y. Hence, besides relying on chemo-haptic information, we found that crayfish can use sight alone to discriminate between different abstract geometrical shapes when macroscopically different. Failure to discriminate between the downright Y and its inversion or a generalization from the presence of a shape with three points creating a simple category, are both likely parsimonious explanations that should be investigated systematically in further studies. A future challenge will be understanding whether crayfish are capable of generalized shape recognition.

Different aspects of reproduction strategies in crayfish: A review

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Yazicioglu B.

2016-01-01

Full Text Available Study of the reproductive strategy of crayfish species is of great importance in the current astacological world. Crayfish are among the largest freshwater invertebrates, and as keystone species, they are able to regulate the structure of the benthic fauna in the freshwaters, demonstrating different ecological strategies and life spans ranging up to 20+ years. In order to bring together the various pieces of information related to this issue, this overview of published scientific reports was conducted. The majority of crayfish species studied show sexual dimorphism, with approximately equal numbers of males and females. However, over some decades numerous observations have been made for a few species that may have different modes of reproduction, such as hermaphroditism or intersex (e.g. Cherax quadricarinatus, Samastacus spinifrons, Parastacus virilastacus and Pacifastacus leniusculus and parthenogenesis (only Procambarus fallax f. virginalis. A recent study showed a new case of parthenogenesis as apomictic parthenogenesis (only Orconectes limosus. In addition, there are many investigations into the reproduction biology of crayfish, including using eyestalk ablation or androgenic gland ablation under various lab conditions and hybridization under natural conditions (e.g. Astacus astacus X Astacus leptodactylus, Orconectes rusticus X Orconectes propinquus. There are also some chemical factors which could possibly affect the reproduction system of crayfish in the wild.

Invasive crayfish threaten the development of submerged macrophytes in lake restoration.

Science.gov (United States)

van der Wal, Jessica E M; Dorenbosch, Martijn; Immers, Anne K; Vidal Forteza, Constanza; Geurts, Jeroen J M; Peeters, Edwin T H M; Koese, Bram; Bakker, Elisabeth S

2013-01-01

Submerged macrophytes enhance water transparency and aquatic biodiversity in shallow water ecosystems. Therefore, the return of submerged macrophytes is the target of many lake restoration projects. However, at present, north-western European aquatic ecosystems are increasingly invaded by omnivorous exotic crayfish. We hypothesize that invasive crayfish pose a novel constraint on the regeneration of submerged macrophytes in restored lakes and may jeopardize restoration efforts. We experimentally investigated whether the invasive crayfish (Procambarus clarkii Girard) affects submerged macrophyte development in a Dutch peat lake where these crayfish are expanding rapidly. Seemingly favourable abiotic conditions for macrophyte growth existed in two 0.5 ha lake enclosures, which provided shelter and reduced turbidity, and in one lake enclosure iron was added to reduce internal nutrient loading, but macrophytes did not emerge. We transplanted three submerged macrophyte species in a full factorial exclosure experiment, where we separated the effect of crayfish from large vertebrates using different mesh sizes combined with a caging treatment stocked with crayfish only. The three transplanted macrophytes grew rapidly when protected from grazing in both lake enclosures, demonstrating that abiotic conditions for growth were suitable. Crayfish strongly reduced biomass and survival of all three macrophyte species while waterfowl and fish had no additive effects. Gut contents showed that crayfish were mostly carnivorous, but also consumed macrophytes. We show that P. clarkii strongly inhibit macrophyte development once favourable abiotic conditions for macrophyte growth are restored. Therefore, expansion of invasive crayfish poses a novel threat to the restoration of shallow water bodies in north-western Europe. Prevention of introduction and spread of crayfish is urgent, as management of invasive crayfish populations is very difficult.

The activity of glutathione S-transferase in hepatopancreas of Procambarus clarkii: seasonal variations and the influence of environmental pollutants.

Science.gov (United States)

Nies, E; Almar, M M; Hermenegildo, C; Monsalve, E; Romero, F J

1991-01-01

1. The glutathione S-transferase activity in hepatopancreas of the American red crayfish Procambarus clarkii after 15 days' acclimatization in tap water aquaria was measured in specimens collected monthly for a whole year, and shows seasonal variation. 2. Previous data on the environmental pollution of Lake Albufera suggest a possible correlation with the activity tested in the different seasons of the year considering the results of non-acclimatized animals.

First evidence of crayfish plaque agent in populations of the marbled caryfish (Procambarus fallux forma virginalis)

NARCIS (Netherlands)

Keller, N.S.; Pfeiffer, M.; Roessink, I.; Schulz, R.; Schrimpf, A.

2014-01-01

The introduction of non-indigenous species and associated diseases can cause declines in indigenous flora and fauna and threaten local biodiversity. The crayfish plague pathogen (Aphanomyces astaci), carried and transmitted by latent infected North American crayfish, can lead to high mortalities in

Relative distribution and abundance of fishes and crayfish in 2010 and 2014 prior to saltcedar (Tamarix ssp.) removal in the Amargosa River Canyon, southeastern California

Science.gov (United States)

Hereford, Mark E.

2016-07-22

The Amargosa River Canyon, located in the Mojave Desert of southeastern California, contains the longest perennial reach of the Amargosa River. Because of its diverse flora and fauna, it has been designated as an Area of Critical Environmental Concern and a Wild and Scenic River by the Bureau of Land Management. A survey of fishes conducted in summer 2010 indicated that endemic Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were abundant and occurred throughout the Amargosa River Canyon. The 2010 survey reported non-native red swamp crayfish (Procambarus clarkii) and western mosquitofish (Gambusia affinis) captures were significantly higher, whereas pupfish captures were lower, in areas dominated by non-native saltcedar (Tamarix ssp.). Based on the 2010 survey, it was hypothesized that the invasion of saltcedar could result in a decrease in native species. In an effort to maintain and enhance native fish populations, the Bureau of Land Management removed saltcedar from a 1,550 meter reach of stream on the Amargosa River in autumn 2014 and autumn 2015. Prior to the removal of saltcedar, a survey of fishes and crayfish using baited minnow traps was conducted in the treatment reach to serve as a baseline for future comparisons with post-saltcedar removal surveys. During the 2014 survey, 1,073 pupfish and 960 speckled dace were captured within the treatment reach. Catch per unit effort of pupfish and speckled dace in the treatment reach was less in 2014 than in 2010, although differences could be owing to seasonal variation in capture probability. Non-native mosquitofish catch per unit effort decreased from 2010 to 2014; however, the catch per unit effort of crayfish increased from 2010 to 2014. Future monitoring efforts of this reach should be conducted at the same time period to account for potential seasonal fluctuations of abundance and distribution of fishes and crayfish. A more robust study design that

Expansion of the marbled crayfish in Slovakia: beginning of an invasion in the Danube catchment?

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Boris Lipták

2016-01-01

Full Text Available The marbled crayfish, Procambarus fallax f. virginalis, is a taxon widely available in the aquarium pet trade, which has been introduced to open waters in several European countries and in Madagascar. Recent studies confirmed this parthenogenetically reproducing crayfish as a high-risk invasive species, and vector of the crayfish plague pathogen, Aphanomyces astaci. It has been first discovered in Slovakia in 2010, but the status of the local population was not studied since then. Due to enlarged sampling area around the first report and one locality, where we presupposed the crayfish occurrence, we identified new marbled crayfish populations. Here, we report presence of three newly established marbled crayfish populations in Slovakia. Two populations are located critically close to the Váh River, a major tributary of the Danube River; one of them being directly connected to the Váh River via a side channel during occasional floods. The third established marbled crayfish population was found at the mouth of a thermal stream flowing into the Nitra River, a tributary of the Váh River. In this stream, crayfish coexist with other exotic fish and gastropod species of aquarium origin. We presume that the reported localities may serve as a source for further expansion of the marbled crayfish in the mid-part of the Danube catchment. Floods, active dispersal (including overland, passive dispersal by zoochory or anthropogenic translocations are among the major drivers facilitating the marbled crayfish colonization. We have not detected the crayfish plague pathogen in any of the studied populations. However, if spreading further, the marbled crayfish will encounter established populations of crayfish plague carriers in the Danube River, in which case they may acquire the pathogen by horizontal transmission and contribute to spread of this disease to indigenous European crayfish species.

Gill ATPase activity in Procambarus clarkii as an indicator of heavy metal pollution

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Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

1989-06-01

Lake Albufera and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic industrial residues, including heavy metals, from the many urban and waste waters of this area. The American red crayfish, Procambarus clarkii have a high resistance to toxic effects of heavy metals. The sublethal effects of heavy metals on gills of fish and aquatic invertebrates have been extensively studied. Some metabolic disturbances and histologic damages have been reported, as well as osmoregulation alterations. However, little work has been done about the effect of heavy metals on Na,K and Mg-ATPases of freshwater invertebrate gills. Na,K-ATPase is the prime mediator of ion transport across cellular membranes and plays a central role in whole body ion regulation in marine and estuarine animals. Na,K-ATPase has been reviewed and assessed as a potentially useful indicator of pollution stress in aquatic animals. The purpose of this study is look for the relation, if any, between crayfish gill ATP-ase activity changes and metal exposure in laboratory. This find would allow the authors to assay this potential indicator in the field.

Are Chinese consumers at risk due to exposure to metals in crayfish? A bioaccessibility-adjusted probabilistic risk assessment.

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Peng, Qian; Nunes, Luís M; Greenfield, Ben K; Dang, Fei; Zhong, Huan

2016-03-01

Freshwater crayfish, the world's third largest crustacean species, has been reported to accumulate high levels of metals, while the current knowledge of potential risk associated with crayfish consumption lags behind that of finfish. We provide the first estimate of human health risk associated with crayfish (Procambarus clarkii) consumption in China, the world's largest producer and consumer of crayfish. We performed Monte Carlo Simulation on a standard risk model parameterized with local data on metal concentrations, bioaccessibility (φ), crayfish consumption rate, and consumer body mass. Bioaccessibility of metals in crayfish was found to be variable (68-95%) and metal-specific, suggesting a potential influence of metal bioaccessibility on effective metal intake. However, sensitivity analysis suggested risk of metals via crayfish consumption was predominantly explained by consumption rate (explaining >92% of total risk estimate variability), rather than metals concentration, bioaccessibility, or body mass. Mean metal concentrations (As, Cd, Cu, Ni, Pb, Se and Zn) in surveyed crayfish samples from 12 provinces in China conformed to national safety standards. However, risk calculation of φ-modified hazard quotient (HQ) and hazard index (HI) suggested that crayfish metals may pose a health risk for very high rate consumers, with a HI of over 24 for the highest rate consumers. Additionally, the φ-modified increased lifetime risk (ILTR) for carcinogenic effects due to the presence of As was above the acceptable level (10(-5)) for both the median (ILTR=2.5×10(-5)) and 90th percentile (ILTR=1.8×10(-4)), highlighting the relatively high risk of As in crayfish. Our results suggest a need to consider crayfish when assessing human dietary exposure to metals and associated health risks, especially for high crayfish-consuming populations, such as in China, USA and Sweden. Copyright © 2016 Elsevier Ltd. All rights reserved.

Putative pacemakers in the eyestalk and brain of the crayfish Procambarus clarkii show circadian oscillations in levels of mRNA for crustacean hyperglycemic hormone.

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Janikua Nelson-Mora

Full Text Available Crustacean hyperglycemic hormone (CHH synthesizing cells in the optic lobe, one of the pacemakers of the circadian system, have been shown to be present in crayfish. However, the presence of CHH in the central brain, another putative pacemaker of the multi-oscillatory circadian system, of this decapod and its circadian transcription in the optic lobe and brain have yet to be explored. Therefore, using qualitative and quantitative PCR, we isolated and cloned a CHH mRNA fragment from two putative pacemakers of the multi-oscillatory circadian system of Procambarus clarkii, the optic lobe and the central brain. This CHH transcript synchronized to daily light-dark cycles and oscillated under dark, constant conditions demonstrating statistically significant daily and circadian rhythms in both structures. Furthermore, to investigate the presence of the peptide in the central brain of this decapod, we used immunohistochemical methods. Confocal microscopy revealed the presence of CHH-IR in fibers and cells of the protocerebral and tritocerebal clusters and neuropiles, particularly in some neurons located in clusters 6, 14, 15 and 17. The presence of CHH positive neurons in structures of P. clarkii where clock proteins have been reported suggests a relationship between the circadian clockwork and CHH. This work provides new insights into the circadian regulation of CHH, a pleiotropic hormone that regulates many physiological processes such as glucose metabolism and osmoregulatory responses to stress.

Determination of chromium in treated crayfish, Procambarus clarkii, by electrothermal ASS: study of chromium accumulation in different tissues

Energy Technology Data Exchange (ETDEWEB)

Hernandez, F.; Diaz, J.; Medina, J.; Del Ramo, J.; Pastor, A.

1986-06-01

In the present study, the authors investigated the accumulation of chromium in muscle, hepatopancreas, antennal glands, and gills of Procambarus clarkii (Girard) from Lake Albufera following Cr(VI)-exposure. Determinations of chromium were made by using Electrothermal Atomic Absorption Spectroscopy and the standard additions method.

A review of ecological interactions between crayfish and fish, indigenous and introduced

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Reynolds J.D.

2011-05-01

Full Text Available Crayfish (decapods and fish are both long-lived large members of freshwater communities, often functioning as keystone species. This paper reviews interactions between these, with emphasis on the European context. Native crayfish and fish are in ecological balance, which may involve mutual predation, competition and sometimes habitat disturbance. This balance is disrupted by range extensions and translocations of native fish or crayfish into exotic situations. Some fish and crayfish have been translocated globally, chiefly from North America to other continents. Non-indigenous crayfish species (NICS may impact on native fish, just as introduced fish impact on indigenous crayfish species (ICS. Competition between ICS and NICS may result in making the former susceptible to various mechanisms of interaction with fish, indigenous or introduced. In Europe, long-established NICS – signals, spiny-cheek and red swamp crayfish – may occur in greater densities than ICS; they are more tolerant and aggressive and show more interactions with fish. More recent introductions, still restricted in distribution, have not yet received enough study for their impacts to be assessed. Interactions between fish and crayfish in North and South America, Madagascar and Australasia are also explored. Mechanisms of interaction between fish and crayfish include mutual predation, competition for food and spatial resources, food-web alteration and habitat modification. Resultant changes in communities and ecosystems may be physical or biotal, and affect both ecosystem services and exploitation potential.

Habitat and co-occurrence of native and invasive crayfish in the Pacific Northwest, USA

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Pearl, Christopher A.; Adams, Michael J.; McCreary, Brome

2013-01-01

Biological invasions can have dramatic effects on freshwater ecosystems and introduced crayfish can be particularly impacting. We document crayfish distribution in three large hydrographic basins (Rogue, Umpqua, Willamette/Columbia) in the Pacific Northwest USA. We used occupancy analyses to investigate habitat relationships and evidence for displacement of native Pacifastacus leniusculus (Dana, 1852) by two invaders. We found invasive Procambarus clarkii (Girard, 1852), in 51 of 283 sites and in all three hydrographic basins. We found invasive Orconectes n. neglectus (Faxon, 1885) at 68% of sites in the Rogue basin and provide first documentation of their broad distribution in the Umpqua basin. We found P. clarkii in both lentic and lotic habitats, and it was positively associated with manmade sites. P. leniusculus was positively associated with lotic habitats and negatively related to manmade sites. In the Rogue and Umpqua basins, O. n. neglectus and P. leniusculus were similar in their habitat associations. We did not find a negative relationship in site occupancy between O. n. neglectus and P. leniusculus. Our data suggest that P. clarkii has potential to locally displace P. leniusculus. There is still time for preventive measures to limit the spread of the invasive crayfish in this region.

Comparison of the response (in terms of accumulation, cellular and genetic impacts) of the crayfish Procambarus clarkii after exposure to a metallic pollutant (cadmium) and to a radiological pollutant (uranium 238 and 233)

International Nuclear Information System (INIS)

Al Kaddissi, S.

2012-01-01

The study of the effects of radionuclides and metals on organisms is necessary for the evaluation of their toxicity and their ecological threats. We first aimed to study the impacts of cadmium (Cd) and Uranium (U) on different biological levels of the crayfish Procambarus clarkii after acute and chronic exposures. We evaluated their impacts on mitochondria, oxidative stress responses, on histological structures, and the survival rates. We tried to connect these effects between them and to the bioaccumulation in the gills and the hepato pancreas. We also tried to discriminate the chemo and the radiotoxicity of U by exposing crayfish to either depleted or enriched U ( 233 U: presenting a higher specific activity) using the same criteria of effects. We demonstrated that the gene mt encoding for the metallothionein was always over-expressed in the presence of Cd. Therefore, it seems to be a good bio-marker of Cd toxicity in P. clarkii. The follow up of mitochondrial genes expressions (12s, atp6 and cox1), showed that both metals affect mitochondria and that their mechanisms of action do not seem to be always the same. We also observed that U generates more oxidative stress than Cd when comparing the expression levels of genes encoding for antioxidants (sod (Mn) and mt) and the enzymatic activities of superoxide dismutase, the catalase, the glutathione peroxidase and the glutathione S transferase. However, the symptoms of histo-pathological damages after Cd and U contamination were similar in both conditions. After comparing the survival rates of the crayfish, we concluded that Cd was more toxic than the radioelement. Moreover, we demonstrated that the toxic effect of U on P. clarkii exposed to a low environmental concentration is mainly due to its chemo-toxicity rather than to its radiotoxicity. We established that, the molecular answers vary according to the intensity and the duration of the chemical stress applied to the organisms. We suggested the use of the

Effects of sublethal exposure to lead on levels of energetic compounds in Procambarus clarkii (Girard, 1852)

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Martinez, M.; Torreblanca, A.; Del Ramo, J.; Diaz-Mayans, J. (Univ. of Valencia (Spain))

1994-05-01

Lead is neither essential nor beneficial to living organisms; all existing data show that its metabolic effects are adverse. Lead is toxic to all phyla of aquatic biota. Most of the lead discharged into surface water is rapidly incorporated into suspended and bottom sediments. The American red crayfish, Procambarus clarkii, lives in a wide range of environmental conditions that include highly polluted waters. Lead present in take sediments can be available to aquatic animals such as P. clarkii because it is a detritivor and burrow into the sediment. In fact, we found remarkable levels of lead in tissues of P. clarkii caught in Albufera Lake and kept 15 days in clean water (e. g. 223 [mu]g/g dry weight in gills). Furthermore, P. clarkii has a high capacity for lead accumulation from water, and gills were the most important tissue of lead accumulation. Among effects that contaminants have on the physiology of the organisms, energetic state variables are important, since they will alter both survival and reproduction. Hepatopancreas is a major site for the energetic reserve in crayfish and is a site of lead accumulation, although metal concentration in this organ is not as high as gills. The purpose of this study was to examine changes in energy reserves in hepatopancreas and gills of the crayfish P. clarkii, in response to sublethal exposure to lead. Gills are directly exposed to contaminants in the environment, and they are the first organ showing alterations by the action of the contaminants. Hepatopancreas was also chosen due to both, its relevance in the energetic metabolism and its role in heavy metal detoxification mechanisms.

Fatty acids and astaxanthin composition of two edible native Mexican crayfish Cambarellus (C.) montezumae and Procambarus (M.) bouvieri; Composición de ácidos grasos y astaxantina de dos especies comestibles de acociles nativos de México, Cambarellus (C.) montezumae y Procambarus.

Energy Technology Data Exchange (ETDEWEB)

Coral-Hinostroza, G.; Diaz-Martinez, M.; Huberman, A.; Silencio-Barrita, J.L.

2016-07-01

The content and composition of the fatty acids (F As) and astaxanthin (AST) in the edible forms of crayfish: the whole animal of Cambarellus (C.) montezumae, and the tail meat (TM) of Procambarus (M.) bouvieri were determined by GC and HPLC. The exoskeleton (EXK) of P. (M.) bouvieri was also studied. Unsaturated FAs, and mostly oleic acid (C18:1 n-9), were predominant in both edible forms. The contents of the polyunsaturated eicosapentaenoic (C20:5 n-3, EPA), arachidonic (C20:4 n-6, ARA) and docosahexaenoic acid (C22:6 n-3, DHA), were higher in the TM of P. (M.) bouvieri than in the complete C. (C.) montezumae (p<0.05). Total carotenoids ranged between 2.31 ± 0.33 μg·g−1 and 66.3 ± 3.91 μg·g−1, and were composed mainly of AST (>79.50%). AST esters were enriched with saturated FAs in C. (C.) montezumae and with PUFAs in EXK of P. (M.) bouvieri. We conclude that both C. (C.) montezumae and the TM of P. (M.) bouvieri are traditional foods rich in n-3 PUFAs and C. (C.) montezumae in AST. The EXK of P. (M.) bouvieri is a rich potential source of AST, n-3 PUFAs, and the combination AST-DHA. [Spanish] Se determinó por GC y HPLC el contenido y composición de ácidos grasos (AGs) y astaxantina (AST), en dos formas comestibles de acocil: el animal completo de Cambarellus (C.) montezumae, y el músculo de la cola (MC) de Procambarus (M.) bouvieri. Adicionalmente, se estudió el exosqueleto (EXK) de P. (M.) bouvieri. En ambas formas comestibles predominaron los AGs insaturados. Los contenidos de ácido eicosapentaenoico (C20:5 n-3, EPA), araquidónico (C20:4 n-6, ARA) y docosahexaenoico (C22: 6 n-3, DHA), fueron mayores en el MC que en C. (C) montezumae (p<0,05). Los carotenoides totales oscilaron de 2.3 ± 0.3 μg·g−1 a 66.3 ± 3.9 μg·g−1, con predominancia de AST (>79.50%). Los ésteres de AST en C. (C.) montezumae fueron enriquecidos con AGs saturados mientras que los del EXK de P. (M.) bouvieri con AGs poliinsaturados. Se concluyó que tanto C. (C

Revisiting reproduction and population structure and dynamics of Procambarus clarkii eight years after its introduction into Lake Trasimeno (Central Italy

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Dörr A.J.M.

2013-06-01

Full Text Available Understanding population dynamics and regulation is fundamental for predicting establishment and spread of invasive alien species. In addition, the population biology of invasive alien species offers an opportunity to study basic ecological processes. In this context, we investigated reproductive and growth plasticity in the invasive crayfish Procambarus clarkii in Lake Trasimeno (central Italy. In total, 3153 crayfish were collected monthly from June 2007 to July 2009. The molt status was assessed by evaluating the exoskeleton hardness. To assess the reproductive cycle, the gonado-somatic and wet hepato-somatic indices were calculated for females. The reproductive status of males was appraised as well. We estimated growth and longevity using the von Bertalanffy growth function, and calculated the total, natural and fishing mortality indices. We then compared our present data with those obtained from the same population eight years before. Our results indicate some changes in population dynamics and in both molting and reproductive periods since the initial invasion of the shallow lake investigated. Long-term differences in the life history of the Trasimeno population may be the result of selective pressures different from those of the native range, but may also result from colonization events and human interference caused by professional fishing activities.

Investigating the genetic and epigenetic basis of big biological questions with the parthenogenetic marbled crayfish: A review and perspectives.

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Vogt, Gunter

2018-03-01

In the last 15 years, considerable attempts have been undertaken to develop the obligately parthenogenetic marbled crayfish Procambarus virginalis as a new model in biology. Its main advantage is the production of large numbers of offspring that are genetically identical to the mother, making this crustacean particularly suitable for research in epigenetics. Now, a draft genome, transcriptome and genome-wide methylome are available opening new windows for research. In this article, I summarize the biological advantages and genomic and epigenetic features of marbled crayfish and, based on first promising data, discuss what this new model could contribute to answering of ''big'' biological questions. Genome mining is expected to reveal new insights into the genetic specificities of decapod crustaceans, the genetic basis of arthropod reproduction, moulting and immunity, and more general topics such as the genetic underpinning of adaptation to fresh water, omnivory, biomineralization, sexual system change, behavioural variation, clonal genome evolution, and resistance to cancer. Epigenetic investigations with the marbled crayfish can help clarifying the role of epigenetic mechanisms in gene regulation, tissue specification, adult stem cell regulation, cell ageing, organ regeneration and disease susceptibility. Marbled crayfish is further suitable to elucidate the relationship between genetic and epigenetic variation, the transgenerational inheritance of epigenetic signatures and the contribution of epigenetic phenotype variation to the establishment of social hierarchies, environmental adaptation and speciation. These issues can be tackled by experiments with highly standardized laboratory lineages, comparison of differently adapted wild populations and the generation of genetically and epigenetically edited strains.

REINTRODUCTION OF NOBLE CRAYFISH ASTACUS ASTACUS AFTER CRAYFISH PLAGUE IN NORWAY

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TAUGBØL T.

2004-01-01

Full Text Available The Glomma and Halden watercourses in Norway were hit by crayfish plague in 1987 and 1989. Reintroduction of the noble crayfish started in 1989 in the Glomma and in 1995 in the Halden watercourse. Norway has especially good conditions for reintroduction of the native crayfish after crayfish plague, as there is no alien plague-carrying crayfish species in the country. In the Glomma watercourse, approx. 15 000 adult crayfish and 10 000 juveniles have been stocked while in the Halden watercourse the figures are 19 000 adults and 26 500 juveniles. All stocking sites were previously regarded as very good crayfish localities. Four years after stocking, natural recruitment was recorded at all adult crayfish stocking sites in the Glomma watercourse and at most sites in the Halden watercourse. Current crayfish density is, however, much lower than pre-plague densities even at the sites where population development has been in progress for more than 10 years. Extensive post-stocking movements were recorded among adult crayfish. Some sites seemed more suitable for settling, resulting in a great variation in CPUE between the different test-fishing sites. Juveniles seem more appropriate as stocking material if the goal is to re-establish a population in a particular area, due to their stationary behaviour, which seems to remain as they grow larger.

A pilot study testing a natural and a synthetic Molluscicide for controlling invasive apple snails (Pomacea maculata)

Science.gov (United States)

Olivier, Heather M.; Jenkins, Jill A.; Berhow, Mark; Carter, Jacoby

2016-01-01

Pomacea maculata (formerly P. insularum), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea (Camellia sinensis) seed derivative (TSD) or niclosamide monohydrate (Pestanal®, 2′,5-dichloro-4′-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish (Procambarus clarkii) and redear sunfish (Lepomis microlophus). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).

Astaxanthin from Crayfish (Procambarus clarkii as a Pigmentary Ingredient in the Feed of Laying Hens

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Garrido-Fernández, J.

2008-06-01

Full Text Available Chicken egg yolks generally owe their color to yellow carotenoids. The addition of synthetic red pigments allows changes in color, from the original yellow to red hues which may be more appealing to consumers in certain markets.Our aim has been to test whether ground crayfish shells, which are a rich and natural source of astaxanthin, produce detectable changes in the coloration of egg yolks through the accumulation of this carotenoid. Laying hens were fed with a commercial feed mixed with crayfish powder and the carotenoid profiles of the yolks in the eggs laid during the trial were monitored by HPLC. The analyses showed a progressive increase in the astaxanthin concentration in the egg yolks, reaching similar levels to those obtained for the rest of present carotenoid pigments.La yema de huevo de gallina debe su coloración a la presencia de carotenoides de tonalidad amarilla. La adición de colorantes sintéticos de tonalidades rojas permite modificar e incrementar la coloración de la yema desde el amarillo original a tonos rojos que pueden ser demandados en ciertos mercados según las preferencias del consumidor. El objetivo del trabajo fue probar si un triturado obtenido a partir de caparazones de cangrejo, que es una fuente natural y rica en astaxanteno, produce cambios detectables en la coloración de la yema de huevo por la acumulación de dicho carotenoide. Las gallinas ponedoras se alimentaron con un pienso comercial al que se adicionó triturado de caparazón de cangrejo. Se realizó un seguimiento de los cambios en la composición carotenoide (mediante HPLC de la yema de los huevos puestos durante el periodo de alimentación suplementada. Los análisis mostraron una progresiva incorporación de astaxanteno que alcanzó niveles similares al resto de carotenoides presentes inicialmente en la yema.

Effects of depth and crayfish size on predation risk and foraging profitability of a lotic crayfish

Science.gov (United States)

Flinders, C.A.; Magoulick, D.D.

2007-01-01

We conducted field surveys and experiments to determine whether observed distributions of crayfish among habitats were influenced by differential resource availability, foraging profitability, and predation rates and whether these factors differed with crayfish size and habitat depth. We sampled available food resources (detritus and invertebrates) and shelter as rock substrate in deep (>50 cm) and shallow (<30 cm) habitats. We used an enclosure-exclosure experiment to examine the effects of water depth and crayfish size on crayfish biomass and survival, and to determine whether these factors affected silt accrual, algal abundance (chlorophyll a [chl a]), and detritus and invertebrate biomass (g ash-free dry mass) differently from enclosures without crayfish. We conducted tethering experiments to assess predation on small (13-17 mm carapace length [CL]) and large (23-30 mm CL) Orconectes marchandi and to determine whether predation rates differed with water depth. Invertebrate biomass was significantly greater in shallow water than in deep water, whereas detritus biomass did not differ significantly between depths. Cobble was significantly more abundant in shallow than in deep water. Depth and crayfish size had a significant interactive effect on change in size of enclosed crayfish when CL was used as a measure of size but not when biomass was used as a measure of size. CL of small crayfish increased significantly more in enclosures in shallow than in deep water, but CL of large crayfish changed very little at either depth. Silt, chl a, and detritus biomass were significantly lower on tiles in large- than in small- and no-crayfish enclosures, and invertebrate biomass was significantly lower in large- than in no-crayfish enclosures. Significantly more crayfish were consumed in deep than in shallow water regardless of crayfish size. Our results suggest that predation and resource availability might influence the depth distribution of small and large crayfish. Small

Toxicity of some ricefield pesticides to the crayfish P. clarkii, under laboratory and field conditions in Lake Albufera (Spain).

Science.gov (United States)

Andreu-Moliner, E S; Almar, M M; Legarra, I; Núñez, A

1986-12-01

Static toxicities in mature crayfish (Procambarus clarkii) were determined, for eight insecticides, two herbicides and one fungicide which were frequently used in rice cultivation at Lake Albufera in Valencia (Spain). Three concentrations of each product were used: a) The concentration that was recommended by the dealer (in mg/L of active ingredient): Carbofuran 0.40, Carbaryl 0.80, Malathion 0.80, Trichlorfon 0.40, Endosulfan 0.56, Lindane 0.56, Fenitrothion 0.40, Cyfloxylate 0.02, Molinate-Thiobencarb 1.50, Copper Sulfate 0.42, b) Half of the recommended concentration. c) Double of the recommended concentration. In all three of the concentrations tested, only Fenitrothion and Cyfloxylate caused a considerable mortality. The other ones do not actually produce any important effects on P. clarkii in our conditions. Nevertheless, insecticides are more toxic than herbicides or fungicides, as the latter show a rather low toxicity.

SIFamide peptides in clawed lobsters and freshwater crayfish (Crustacea, Decapoda, Astacidea): a combined molecular, mass spectrometric and electrophysiological investigation.

Science.gov (United States)

Dickinson, Patsy S; Stemmler, Elizabeth A; Cashman, Christopher R; Brennan, Henry R; Dennison, Bobbi; Huber, Kristen E; Peguero, Braulio; Rabacal, Whitney; Goiney, Christopher C; Smith, Christine M; Towle, David W; Christie, Andrew E

2008-04-01

Recently, we identified the peptide VYRKPPFNGSIFamide (Val(1)-SIFamide) in the stomatogastric nervous system (STNS) of the American lobster Homarus americanus using matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry (MALDI-FTMS). Given that H. americanus is the only species thus far shown to possess this peptide, and that a second SIFamide isoform, Gly(1)-SIFamide, is broadly conserved in other decapods, including another astacidean, the crayfish Procambarus clarkii, we became interested both in confirming our identification of Val(1)-SIFamide via molecular methods and in determining the extent to which this isoform is conserved within other members of the infraorder Astacidea. Here, we present the identification and characterization of an H. americanus prepro-SIFamide cDNA that encodes the Val(1) isoform. Moreover, we demonstrate via MALDI-FTMS the presence of Val(1)-SIFamide in a second Homarus species, Homarus gammarus. In contrast, only the Gly(1) isoform was detected in the other astacideans investigated, including the lobster Nephrops norvegicus, a member of the same family as Homarus, and the crayfish Cherax quadricarinatus, P. clarkii and Pacifastacus leniusculus, which represent members of each of the extant families of freshwater astacideans. These results suggest that Val(1)-SIFamide may be a genus (Homarus)-specific isoform. Interestingly, both Val(1)- and Gly(1)-SIFamide possess an internal dibasic site, Arg(3)-Lys(4), raising the possibility of the ubiquitously conserved isoform PPFNGSIFamide. However, this octapeptide was not detected via MALDI-FTMS in any of the investigated species, and when applied to the isolated STNS of H. americanus possessed little bioactivity relative to the full-length Val(1) isoform. Thus, it appears that the dodeca-variants Val(1)- and Gly(1)-SIFamide are the sole bioactive isoforms of this peptide family in clawed lobsters and freshwater crayfish.

The Impacts of flow alterations to crayfishes in Southeastern Oklahoma, with an emphasis on the mena crayfish (orconectes menae)

Science.gov (United States)

Brewer, Shannon K.; Dyer, Joseph J.

2016-01-01

Human activities can alter the environment to the point that it is unsuitable to the native species resulting in a loss of biodiversity. Ecologists understand the importance of biodiversity and the conservation of vulnerable species. Species that are narrowly endemic are considered to be particularly vulnerable because they often use specific habitats that are highly susceptible to human disturbance. The basic components of species conservation are 1) delineation of the spatial distribution of the species, 2) understanding how the species interacts with its environment, and 3) employing management strategies based on the ecology of the species. In this study, we investigated several crayfish species endemic to the Ouachita Mountains in Oklahoma and Arkansas. We established the spatial distributions (i.e., range) of the crayfish using Maximum Entropy species distribution modeling. We then investigated crayfish habitat use with quantitative sampling and a paired movement study. Finally, we evaluated the ability of crayfish to burrow under different environmental conditions in a controlled laboratory setting. Crayfish distribution at the landscape scale was largely driven by climate, geology and elevation. In general, the endemic crayfish in this study occurred above 300-m elevation where the geology was dominated by sandstone and shale, and rainfall totals were the highest compared to the rest of the study region. Our quantitative data indicated crayfish did not select for specific habitat types at the reach scale; however, crayfish appeared to continue to use shallow and dry habitat even as the streams dried. Movement by passive integrated transponder (PIT) tagged crayfish was highly variable but crayfish tended to burrow in response to drought rather than migrate to wet habitat. Controlled laboratory experiments revealed smaller substrate size (pebble) restricted crayfish burrowing more than larger substrates (cobble). We also found excess fine sediment restricted

Temporal variation in the prevalence of the crayfish plague pathogen, Aphanomyces astaci, in three Czech spiny-cheek crayfish populations

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Matasová K.

2011-06-01

Full Text Available North American crayfish species are natural hosts of the crayfish plague pathogen Aphanomyces astaci. The spiny-cheek crayfish Orconectes limosus, widespread in Central Europe, is the main reservoir of A. astaci in Czech Republic. We tested if there are temporal changes in the prevalence of infected individuals (i.e., the proportion of individuals in which the pathogen is detected in spiny-cheek crayfish populations. Crayfish from three populations shown previously to be infected to different extents (high, intermediate and low, were repeatedly sampled in different years (2004–2010 and seasons. The presence of A. astaci in the soft abdominal crayfish cuticle was tested by specific amplification of the pathogen DNA. There was no substantial temporal variation in pathogen prevalence in the highly and very lowly infected populations. However, a significant long-term as well as seasonal decrease was found in the intermediately infected population. This decline could be related to a decrease in population density over the studied years, and to crayfish seasonal moulting, respectively. A reliable estimate of pathogen prevalence in American crayfish populations thus requires repeated monitoring over years, preferably during the same season before the main period of crayfish moulting.

Risk assessment of pet-traded decapod crustaceans in the Republic of Kazakhstan, the leading country in Central Asia

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Uderbayev Talgat

2017-01-01

Full Text Available The pet trade with decapod crustaceans has been considered one of the main pathway of introduction of these animals worldwide. As the leading markets in this regards are the Czech Republic, Germany and the USA. Central Asia is not perceived as an important market with ornamental decapod crustaceans. Despite this assumption, we found at least 16 species of freshwater shrimp, crayfish and crab species pet-traded in the Republic of Kazakhstan, the largest country in this region. Considering computed risk assessment, the origin of particular species, their availability on the market, the probability of establishment and further aspects, we identified two crayfish Procambarus clarkii and Procambarus fallax f. virginalis being the seriously hazardous taxa with high potential to threaten native crayfish species as well as inhabited ecosystems. To prevent their introductions and to minimize the risks of mentioned species, similarly as in the case of European Union, we recommend the total ban of import, trade and keeping of these high-risk taxa within Central Asia.

Characterization of a molt-inhibiting hormone (MIH) of the crayfish, Orconectes limosus, by cDNA cloning and mass spectrometric analysis.

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Bulau, Patrick; Okuno, Atsuro; Thome, Elke; Schmitz, Tina; Peter-Katalinic, Jasna; Keller, Rainer

2005-11-01

The structure of the precursor of a molt-inhibiting hormone (MIH) of the American crayfish, Orconectes limosus was determined by cloning of a cDNA based on RNA from the neurosecretory perikarya of the X-organ in the eyestalk ganglia. The open reading frame includes the complete precursor sequence, consisting of a signal peptide of 29, and the MIH sequence of 77 amino acids. In addition, the mature peptide was isolated by HPLC from the neurohemal sinus gland and analyzed by ESI-MS and MALDI-TOF-MS peptide mapping. This showed that the mature peptide (Mass 8664.29 Da) consists of only 75 amino acids, having Ala75-NH2 as C-terminus. Thus, C-terminal Arg77 of the precursor is removed during processing, and Gly76 serves as an amide donor. Sequence comparison confirms this peptide as a novel member of the large family, which includes crustacean hyperglycaemic hormone (CHH), MIH and gonad (vitellogenesis)-inhibiting hormone (GIH/VIH). The lack of a CPRP (CHH-precursor related peptide) in the hormone precursor, the size and specific sequence characteristics show that Orl MIH belongs to the MIH/GIH(VIH) subgroup of this larger family. Comparison with the MIH of Procambarus clarkii, the only other MIH that has thus far been identified in freshwater crayfish, shows extremely high sequence conservation. Both MIHs differ in only one amino acid residue ( approximately 99% identity), whereas the sequence identity to several other known MIHs is between 40 and 46%.

Garden ponds as potential introduction pathway of ornamental crayfish

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Patoka J.

2014-01-01

Full Text Available The private stocking of ornamental crayfish in garden ponds was discussed in previous studies, but there is a lack of detailed analysis for better understanding of this introduction pathway. The Czech Republic is one of leading EU countries in trade with ornamental crayfish and private garden ponds are popular among people. The crayfish keepers in the country were interviewed by self-administered questionnaire to gather data about principal characteristics of the keepers and detailed information about crayfish breeding that are of interest for conservation managers. Besides of releasing crayfish into garden ponds, alarming illegal behavior such as releasing of juvenile crayfish into the wild, and capturing of indigenous crayfish from wild populations, were registered. Therefore focusing on public education to increase awareness of possible unwanted consequences of crayfish release and introduction of an obligation to inform customers about hazardousness of non-indigenous crayfish species for retailers and wholesalers is recommended.

Residue analysis of sixty pesticides in red swamp crayfish using QuEChERS with high-performance liquid chromatography-tandem mass spectrometry

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In this study, a multi-residue analytical method using QuEChERS extraction and dispersive solid-phase extraction (d-SPE) cleanup followed by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) was developed for rapid determination of 60 pesticide residues in whole crayfish a...

[A new method of therapy for branchiobdellosis in crayfish].

Science.gov (United States)

Lohniský, K

1979-02-01

Crayfish (Astacus fluviatilis Fabricius, 1793) were treated three times with a bath of diluted ammonia water and proflavine for four and six minutes at a temperature of 18 degrees C to get rid of the ectoparasitic worms of Branchiobdella parasita Henle, 1835; the hatching ability of the Branchiobdella parasita eggs was stopped after the treatment. No lethal effect of the bath on the crayfish of 5 to 14 cm was observed, the lethal effect on the young crayfish borne on the uropods of the female crayfish cannot be eliminated: during the baths the young crayfish died (the death rate was approximately 6% of the average fertility of crayfish); the young crayfish may have been damaged during the treatment operations with the crayfish. The bath of diluted ammonia water and proflavine may be recommended for the treatment of branchiobdellosis in crayfish to be planted, or after several-hour storage of crayfish supplied to the market. One replication of the above cycle is sufficient according to the results obtained. The ammonia content in the ammonia water depends also on the duration of storage and on the storage temperature--it can drop during the storage. Therefore the ammonia water should be used as soon as possible after the despatchment from the place of production; the ammonia content should be determined by means of titration before preparing the bath, and according to this content the dilution ratio should be adjusted.

Habitat associations of three crayfish endemic to the Ouachita Mountain Ecoregion

Science.gov (United States)

Dyer, Joseph J.; Brewer, Shannon K.

2018-01-01

Many crayfish are of conservation concern because of their use of unique habitats and often narrow ranges. In this study, we determined fine-scale habitat use by 3 crayfishes that are endemic to the Ouachita Mountains, in Oklahoma and Arkansas. We sampled Faxonius menae (Mena Crayfish), F. leptogonopodus (Little River Creek Crayfish), and Fallicambarus tenuis (Ouachita Mountain Crayfish) from wet and dry erosional channel units of 29 reaches within the Little River catchment. We compared channel-unit and microhabitat selection for each species. Crayfish of all species and life stages selected erosional channel units more often than depositional units, even though these sites were often dry. Accordingly, crayfish at all life stages typically selected the shallowest available microhabitats. Adult crayfish of all species and juvenile Little River Creek Crayfish selected patches of coarse substrate, and all crayfish tended to use the lowest amount of bedrock available. In general, we showed that these endemic crayfish used erosional channel units of streams, even when the channel units were dry. Conservation efforts that protect erosional channel units and mitigate actions that cause channel downcutting to bedrock would benefit these crayfish, particularly during harsh, summer drying periods.

Practical disinfection chemicals for fishing and crayfishing gear against crayfish plague transfer

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Jussila J.

2014-01-01

Full Text Available We tested four commercial disinfectants against crayfish plague (Aphanomyces astaci spores in both aquatic solutions and with material mimicking fishing and crayfishing gear, e.g. traps, ropes, mesh, etc. The tested disinfectants were Proxitane®5:14, Proxitane®12:20, Wofasteril®E400, Virkon®S and hydrogen peroxide. The effects of the chemicals were initially tested in liquid zoospore cultures and the effective concentrations were then further tested using clean and dirty model materials (PP sheet, nylon rope, cotton fabric contaminated with A. astaci spore solutions. The disinfectants effective against infective crayfish plague spores with both clean and dirty model materials were Proxinate®5:14 (effective concentration was 30 mg·L-1 of PAA and Virkon®S (3 g·L-1, while Proxinate®12:20 (10 mg·L-1 of PAA and Wofasteril®E400 (30 mg·L-1 of PAA worked only with clean model materials. Hydrogen peroxide was not effective in the tested concentrations and conditions. Based on the results, the disinfectants most suitable for the fishing and crayfishing gear disinfection would be Proxitane®5:14 and Virkon®S, with the condition that all the gear should be thoroughly cleaned of organic matter to ensure inactivation of A. astaci spores.

DISTRIBUTION OF CRAYFISH IN EUROPE AND SOME ADJOINING COUNTRIES

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HOLDICH D. M.

2002-07-01

Full Text Available The distribution of crayfish in Europe is examined using information from a variety of sources mainly for the last two decades. All European countries have at least one indigenous crayfish species (ICS, many with large stocks, and most countries in Western Europe have at least one non-indigenous crayfish species (NICS. Some species termed indigenous in certain countries may have been introduced in relatively recent times. However, the meaning of the term indigenous (native varies between countries. NICS continue to expand their ranges and present a continued threat to ICS through competition and transmission of diseases, notably crayfish plague. The current high level of interest in crayfish means that many countries are monitoring their crayfish situation and, where necessary, taking steps to renew stocks of threatened indigenous species, some of which are apparently on the verge of extinction. A more regular monitoring programme for European crayfish as a whole is needed if the demise of indigenous species is to be prevented.

Status and management of noble crayfish Astacus astacus in Estonia

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T. Paaver

2009-01-01

Full Text Available Noble crayfish Astacus astacus (L. is an indigenous and the only crayfish species in Estonia. It is potentially endangered by invasion of alien species, diseases and habitat deterioration but does not have legal protected status and is fished only for recreational purpose. Crayfish Working Group of Ministry of Environment and Department of Aquaculture of the Estonian University of Life Sciences have developed crayfish conservation and management plan. Since 1994 standardized test fishing with traps (which catch only crayfish over 7 cm TL has been carried out and database of these fishings shows, that crayfish is dwelling in more than 255 sites in the lakes, rivers, streams, artificial reservoirs. In 52% of monitored sites populations are weak, catch per trap night is below 1 specimen. Exceptionally rich is the stock on the island Saaremaa, where in 59% of populations catch per trap night is over 4 and can reach 50. Licensed recreational catch is allowed in regions, where monitoring data show good status of crayfish stock. It is not allowed to sell the crayfish caught on recreational license. Crayfishing season is limited with August, size limit in recreational fishery is 11 cm TL. There are 10 operating crayfish farms and 15 are under construction. The farms produce yearly around 1000 kg of commercial size crayfish for export to Finland. Over 200000 juveniles are produced for restocking yearly. Restocking projects e.g. restoration of populations, which have been lost because of plague have been successful. The main threat factor is crayfish plague. In 2006–2007 it destroyed the stock of crayfish farms of companies Veteko, Pähkla, Astacus and wild population of Põduste river on the island Saaremaa.

Impacts of drought and crayfish invasion on stream ecosystem structure and function

Science.gov (United States)

Magoulick, Daniel D.

2014-01-01

Drought and seasonal drying can be important disturbance events in many small streams, leading to intermittent or isolated habitats. Many small streams contain crayfish populations that are often keystone or dominant species in these systems. I conducted an experiment in stream mesocosms to examine the effects of drought and potential ecological redundancy of a native and invasive crayfish species. I examined the effects of drought (drought or control) and crayfish presence (none, native crayfish Orconectes eupunctus or invasive crayfish Orconectes neglectus) on stream mesocosm structure and function (leaf breakdown, community metabolism, periphyton, sediment and chironomid densities) in a fully factorial design. Each mesocosm contained a deep and shallow section, and drought treatments had surface water present (5-cm depth) in deep sections where tiles and leaf packs were placed. Drought and crayfish presence did not interact for any response variable. Drought significantly reduced leaf breakdown, and crayfish presence significantly increased leaf breakdown. However, the native and invasive crayfish species did not differ significantly in their effects on leaf breakdown. Drought significantly reduced primary production and community respiration overall, whereas crayfish presence did not significantly affect primary production and community respiration. Neither drought nor crayfish presence significantly affected periphyton overall. However, drought significantly reduced autotrophic index (AI), and crayfish presence increased AI. Inorganic sediment and chironomid density were not affected by drought, but both were significantly reduced by crayfish presence. O. eupunctus reduced AI and sediment more than O. neglectus did. Neither drought nor crayfish species significantly affected crayfish growth or survival. Drought can have strong effects on ecosystem function, but weaker effects on benthic structure. Crayfish can have strong effects on ecosystem

Freshwater crayfish invasions in South Africa: past, present and ...

African Journals Online (AJOL)

Freshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims to indicate which areas are at risk from invasion.

MINIMISING LOSS OF CRAYFISH AND HABITATDURING WORKS ON WATERCOURSES

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PEAY S.

2003-04-01

Full Text Available Works in watercourses with white-clawed crayfish Austropotamobius pallipes cause temporary or permanent loss of habitat and crayfish. Past modifications can also leave waterbodies unfavourable for crayfish, but sometimes there is scope to improve them. Mitigation measures can reduce the impact and reinstate or even improve habitat. Various case studies show measures used during engineering works and some of the problems. Good planning and supervision are vital. The big issues at river and catchment scales (non-indigenous crayfish, disease, water quality and landuse may be higher priorities than provision of habitat at site or reach level; e.g. fencing in pastures improves riparian areas for crayfish and other species. If necessary, there are various options for natural and artificial refuges, but their success depends on flow characteristics, substrate and accessibility. Microhabitat can make the difference between success and failure.

A synthetic phylogeny of freshwater crayfish: insights for conservation

Science.gov (United States)

Owen, Christopher L.; Bracken-Grissom, Heather; Stern, David; Crandall, Keith A.

2015-01-01

Phylogenetic systematics is heading for a renaissance where we shift from considering our phylogenetic estimates as a static image in a published paper and taxonomies as a hardcopy checklist to treating both the phylogenetic estimate and dynamic taxonomies as metadata for further analyses. The Open Tree of Life project (opentreeoflife.org) is developing synthesis tools for harnessing the power of phylogenetic inference and robust taxonomy to develop a synthetic tree of life. We capitalize on this approach to estimate a synthesis tree for the freshwater crayfish. The crayfish make an exceptional group to demonstrate the utility of the synthesis approach, as there recently have been a number of phylogenetic studies on the crayfishes along with a robust underlying taxonomic framework. Importantly, the crayfish have also been extensively assessed by an IUCN Red List team and therefore have accurate and up-to-date area and conservation status data available for analysis within a phylogenetic context. Here, we develop a synthesis phylogeny for the world's freshwater crayfish and examine the phylogenetic distribution of threat. We also estimate a molecular phylogeny based on all available GenBank crayfish sequences and use this tree to estimate divergence times and test for divergence rate variation. Finally, we conduct EDGE and HEDGE analyses and identify a number of species of freshwater crayfish of highest priority in conservation efforts. PMID:25561670

Exponential increase of signal crayfish in running waters in Sweden – due to illegal introductions?

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Bohman P.

2011-07-01

Full Text Available Sweden has only one indigenous species of crayfish, the noble crayfish (Astacus astacus, Fabricius. There has been a steady decline of noble crayfish populations in Sweden since 1907, mainly due to the crayfish plague. To substitute the noble crayfish fishery lost, the Swedish government launched a large-scale introduction of the signal crayfish (Pacifastacus leniusculus Dana. Today, the signal crayfish is regarded as a chronic carrier of the crayfish plague, and an expansion of the species may seriously threaten the noble crayfish. This paper examines the decrease of noble crayfish populations, and the concurrent expansion of signal crayfish in running waters. Data from the Swedish Electrofishing RegiSter (SERS was used. We found that in 1980–1984 the noble crayfish occurred in 4.5% of the studied river sections. In 2008–2009 the occurrences had decreased to 1.9%. In contrast, the signal crayfish had increased in occurrence, from 0.2% (1980–1984 to 11.8% in (2008–2009. We studied the number of stocking permits for signal crayfish introductions, and the available signal crayfish population from the open fishery in Lake Vättern, as possible causes of this expansion. A negative correlation between stocking permits and increased occurrence in streams, and a positive correlation between the availability of crayfish in Lake Vättern and the occurrence in streams was found. This suggests that the expansion of signal crayfish may be due to illegal introductions, further endangering the endemic noble crayfish.

THE FRESHWATER CRAYFISH AUSTROPOTAMOBIUS PALLIPESIN SOUTH TYROL: HERITAGE SPECIES AND BIOINDICATOR

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FÜREDER L.

2003-04-01

Full Text Available Rapid decline of crayfish in European freshwaters and continuing threat necessitate integrated actions in conservation and management of native crayfish populations. Besides biological reasons (diseases, plague, the impact of toxic and harmful substances (fertilisers, herbicides or wastewater effluents, habitat alteration or fragmentation have been responsible for their decline in some regions. The same is true for the region of South Tyrol, where compared to previous investigations, only 10 of a former total of 15 crayfish locations in the water bodies could be affirmed. Although two new populations of the non-indigenous Astacus astacus were detected, the native Austropotamobius pallipes continues to decline. While many investigations have focused accurately on causal coherences for the decline of native populations, the properties of crayfish facilitate to reverse the situation. In a few examples, the potential of Austropotamobius pallipes, the native crayfish in South Tyrol, as “surrogate species” for effective biological conservation is discussed. Given the various adequate attributes of freshwater crayfish as surrogate species (including indicator species, umbrella species and flagship species qualities, they may help to advance not only the crayfish situation itself but also freshwater ecosystem properties in general.

Continental-wide distribution of crayfish species in Europe: update and maps

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Kouba A.

2014-01-01

Full Text Available Recently published astacological studies substantially improved available data on distribution of crayfish in various European regions. At the same time, spread of invasive species has been recorded, additional non-indigenous species became established in various countries, and losses of populations of native species due to crayfish plague and other negative factors were observed. We overview recent advances in this knowledge, and provide updated colour maps of the distribution of all crayfish species present in Europe. These maps are originally based on the data from the Atlas of Crayfish in Europe published in 2006 as a result of the CRAYNET project, and were further updated from more recently published reports, grey literature, and especially thanks to contributions and feedback of over 70 specialists from 32 countries. Separate maps are available for all indigenous crayfish species in Europe as well as for three most widespread non-indigenous crayfish species. Additionally, two maps give locations of known findings of crayfish species introduced to Europe after 1980. These newly established alien species have so far restricted distributions; however, the frequency of recent reports suggests that findings of such species resulting from releases of aquarium pets will further increase.

Signal crayfish as zoogeomorphic agents: diel patterns of fine sediment suspension in a crayfish-affected river and the implications for fine sediment fluxes and dynamics

Science.gov (United States)

Rice, Stephen; Johnson, Matthew; Reeds, Jake; Longstaff, Holly; Extence, Chris

2013-04-01

The signal crayfish (Pacifasticus leniusculus) is a formidable invasive species that has had a deleterious impact on native freshwater fauna across Europe. We contend that the impact of this animal extends beyond ecology into geomorphology and hypothesise that crayfish are significant agents of fine sediment recruitment and mobilisation, with potentially profound impacts on water quality, substrate quality and fine sediment fluxes. Building on pioneering work by colleagues at Queen Mary University, London this poster considers the role of crayfish in fine sediment suspension in a lowland, gravel-bed river. The hypothesis that nocturnal increases in crayfish activity are associated with a greater frequency of sediment suspension events and increases in ambient turbidity, is tested. Strong diel fluctuations in water turbidity were recorded at several sites on the Brampton Arm of the River Nene in England, a river heavily populated by signal crayfish, during August and September 2012. With the exception of three summer flood events, stage measurements during the same period were essentially flat, ruling out a hydraulic cause for overnight rises in turbidity. Water samples collected at midnight and at midday at one site confirm this diel pattern for suspended sediment concentration. Higher mean turbidity values overnight are associated with an increase in the magnitude and frequency of isolated turbidity spikes or events and this is consistent with crayfish nocturnalism. In particular, we suspect that turbidity events are caused by the construction and maintenenance of burrows and by interactions between crayfish and the river bed while foraging, fighting and avoiding each other. Tying the diel SSC signal directly to crayfish activity proved difficult, but several lines of argument presented here suggest that crayfish are the most likely cause of the diel pattern. These results provide substantial support for the idea that signal crayfish are important zoogeomorphic

Monitoring of noble, signal and narrow-clawed crayfish using environmental DNA from freshwater samples

DEFF Research Database (Denmark)

Agersnap, Sune; Larsen, William Brenner; Knudsen, Steen Wilhelm

2017-01-01

human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities. Knowledge about crayfish distribution...

Parasites of crayfish ( P. clarki ) and lobsters ( Macrobrachium ...

African Journals Online (AJOL)

Studies on parasites of crayfish and lobsters as indicators of metal pollution in Great Kwa River, Nigeria was evaluated using appropriate instruments for determination of Physicochemical parameters and detection of metals. Formol ether centrifugation method was used for isolation of parasites. A total of 150 crayfish and ...

Double blow: Alien crayfish infected with invasive temnocephalan in South African waters

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Louis du Preez

2013-09-01

Full Text Available Trade in live, freshwater crayfish for ornamental markets, as well as for aquaculture, has grown rapidly and has become the major pathway for the introduction of non-indigenous crayfish species to several countries worldwide. Here we report on the first record of the Australian "redclaw" Cherax quadracarinatus in the natural waters of a game reserve in South Africa. To compound the situation, these redclaw crayfish were infected with a non-indigenous temnocephalan flatworm parasite. Both crayfish and temnocephalan were in full breeding condition, with young. Further spreading of this crayfish to the subtropical, water-rich, northern KwaZulu-Natal Province of South Africa and southern Mozambique is predicted. Not only might the crayfish compete with indigenous aquatic invertebrates but the non-host-specific temnocephalan might transfer to local decapods, such as freshwater crabs.

UNDERSTANDING AND MANAGING BIODIVERSITY IN RELATION TO NATIVE CRAYFISH POPULATIONS IN EUROPE

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GHERARDI F.

2003-04-01

Full Text Available The loss or diminution of European crayfish populations because of both habitat deterioration and competition with alien crayfish – also responsible for the dissemination of the crayfish plague – would reduce the biodiversity at the species level. The topic “What is meant by biodiversity?” in the context of native freshwater crayfish in Europe was discussed during the Kilkenny CRAYNET meeting in order to make the point about the varied meanings of biodiversity from genes and individuals to population levels.

The potential for using red claw crayfish and hybrid African catfish as ...

African Journals Online (AJOL)

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After 15 days, both crayfish and ...

Do culverts impact the movements of the endangered white-clawed crayfish?

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Louca V.

2014-01-01

Full Text Available Culverts can impact the migration and dispersal of aquatic animals and result in population fragmentation, increasing the risk of local extinction for endangered species such as the white-clawed crayfish Austropotamobius pallipes. This study used radio telemetry and passive integrated transponder (PIT telemetry to determine whether existing and experimental covered culverts affect the upstream and downstream movements of adult white-clawed crayfish. Daily crayfish movement rates did not differ significantly between an unlit 363-m long culvert and open stream channel sections. Crayfish moved into dark, covered sections volitionally. However, limited upstream movement occurred at sudden transitions of bed height or smooth-concrete box culvert sections with fast flow, suggesting partial barrier effects. In the 20-m long experimental in-stream culvert, also dark, but with natural stream bed, 70% of radio-tagged crayfish released downstream entered the culvert, as did 60% of those released upstream. Overall 35% passed through, with similar numbers in each direction. We conclude that dark culverts up to several hundred metres do not inhibit dispersal of white-clawed crayfish, provided stream slope, bed type and water velocity are amenable for movement and refuge. Care is required to ensure that culverts are bioengineered to ensure that average water velocity is sufficiently low and local hydraulic variation high, the bed and/or sidewalls contain refuge structures, and there are no cross-channel steps in bed level. Smooth-bedded box culverts are unlikely to be suitable for white-clawed crayfish.

Sensory Systems and Environmental Change on Behavior during Social Interactions

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S. M. Bierbower

2013-01-01

Full Text Available The impact of environmental conditions for transmitting sensory cues and the ability of crayfish to utilize olfaction and vision were examined in regards to social interactive behavior. The duration and intensity of interactions were examined for conspecific crayfish with different sensory abilities. Normally, vision and chemosensory have roles in agonistic communication of Procambarus clarkii; however, for the blind cave crayfish (Orconectes australis packardi, that lack visual capabilities, olfaction is assumed to be the primary sensory modality. To test this, we paired conspecifics in water and out of water in the presence and absence of white light to examine interactive behaviors when these various sensory modalities are altered. For sighted crayfish, in white light, interactions occurred and escalated; however, when the water was removed, interactions and aggressiveness decreased, but, there was an increase in visual displays out of the water. The loss of olfaction abilities for blind cave and sighted crayfish produced fewer social interactions. The importance of environmental conditions is illustrated for social interactions among sighted and blind crayfish. Importantly, this study shows the relevance in the ecological arena in nature for species survival and how environmental changes disrupt innate behaviors.

Intensive removal of signal crayfish (Pacifastacus leniusculus) from rivers increases numbers and taxon richness of macroinvertebrate species.

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Moorhouse, Tom P; Poole, Alison E; Evans, Laura C; Bradley, David C; Macdonald, David W

2014-02-01

Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non-eradication-oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates.

Assessing the importance of food for improving noble crayfish culture conditions

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Rusch J.C.

2015-01-01

Full Text Available Captive breeding and crayfish culture are considered important measures in species protection activities. Thus, knowledge on optimal feeding of crayfish in captivity is needed in order to secure minimal mortality and prevent detrimental effects to health. To optimize conditions of crayfish prior to subsequent stocking, feeding trials were conducted with the aim of investigating the connection between food intake, food preference and temperature under near natural conditions. During a five-month period, noble crayfish were fed on fish, carrots, algae and chironomid-larvae according to a pre-defined rotation system, whereby the ambient water temperature ranged from 5 °C to 13 °C, following the natural temperature regime. The results of these feeding trials demonstrate a direct correlation between rising temperature and increasing food intake for water temperatures exceeding 8 °C. Food intake is further influenced by the variety of food items available at any one time. The results also confirm that Astacus astacus has a strong preference for fish and that alternation of food types has an impact on consumption. Our results prompt the following recommendations for optimized feeding conditions of crayfish in captivity prior to their release: (1 a balanced diet containing not only plant tissue but also a significant proportion of animal tissue and (2 the amount of available food must be adjusted according to the carapace length of the crayfish.

Status of the white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858, in Spain : distribution and legislation

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ALONSO F.

2000-01-01

Full Text Available The white-clawed crayfish, Austropotamobius pallipes, is the only native species of freshwater crayfish in Spain. This species sustained a first-magnitude inland fishery up to the end of 1970's, when the crayfish plague struck the Spanish waters. It is detected an overall loss of distribution area of populations inhabiting the medium and lower reaches of the main river catchments, especially in Southern and Central Spain. The number of surviving populations can be estimated in ca. 700. Remaining native crayfish populations currently inhabit marginal areas. The populations are very fragmented, occupy short stretches, and are frequently isolated from the main river system. The current distribution is the result of a sum of different factors, i.e. crayfish plague, habitat alterations, extreme climatic drought, etc. The incidence and relative importance of each one varied during the last 15 years, with crayfish plague being a predominant negative factor in the seventies and eighties, and climatic drought in the nineties. The current trend of disappearance is a sufficient reason to consider the native crayfish as at risk of extinction. However neither the national legislation nor most of the regional government legislations have listed this species as endangered. An analysis of the legislation dealing with freshwater crayfish in Spain shows : (a an uneven and generally low level of protection given to the native species and (b a very complex fishing and commercialization regulations for crayfish that show significant changes from one region to another. This complex legislation, complemented with a general lack of data on crayfish populations, low levels of management and public involvement, and different strategies in regional governments regarding restocking programs with exotic species, makes a confusing situation. In order to decrease the general tendency of regression of A. pallipes a conservation program for this species needs to be implemented

Stream permanence influences crayfish occupancy and abundance in the Ozark Highlands, USA

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Yarra, Allyson N.; Magoulick, Daniel D.

2018-01-01

Crayfish use of intermittent streams is especially important to understand in the face of global climate change. We examined the influence of stream permanence and local habitat on crayfish occupancy and species densities in the Ozark Highlands, USA. We sampled in June and July 2014 and 2015. We used a quantitative kick–seine method to sample crayfish presence and abundance at 20 stream sites with 32 surveys/site in the Upper White River drainage, and we measured associated local environmental variables each year. We modeled site occupancy and detection probabilities with the software PRESENCE, and we used multiple linear regressions to identify relationships between crayfish species densities and environmental variables. Occupancy of all crayfish species was related to stream permanence. Faxonius meeki was found exclusively in intermittent streams, whereas Faxonius neglectus and Faxonius luteushad higher occupancy and detection probability in permanent than in intermittent streams, and Faxonius williamsi was associated with intermittent streams. Estimates of detection probability ranged from 0.56 to 1, which is high relative to values found by other investigators. With the exception of F. williamsi, species densities were largely related to stream permanence rather than local habitat. Species densities did not differ by year, but total crayfish densities were significantly lower in 2015 than 2014. Increased precipitation and discharge in 2015 probably led to the lower crayfish densities observed during this year. Our study demonstrates that crayfish distribution and abundance is strongly influenced by stream permanence. Some species, including those of conservation concern (i.e., F. williamsi, F. meeki), appear dependent on intermittent streams, and conservation efforts should include consideration of intermittent streams as an important component of freshwater biodiversity.

MANAGEMENT STRATEGIES, YIELD AND POPULATION DEVELOPMENT OF THE NOBLE CRAYFISH ASTACUS ASTACUS IN LAKE STEINSFJORDEN

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SKURDAL J.

2002-07-01

Full Text Available Lake Steinsfjorden is the most important noble crayfish locality in Norway. The crayfish population has been monitored annually since 1979 including data on total trapping effort, yield and population composition before and after the catching season. The harvest has ranged from 0.7-4.7 kg.ha-1. The catch per trap night decreased prior to 1991 and the yield was reduced by some 50% over the years 1987-1992 as compared to 1979-1986. This was due to removal of small crayfish, high exploitation and the establishment of dense stands of Canadian pondweed (Elodea canadensis. Baited traps catch a large fraction of crayfish < 95 mm total length minimum size. These should according to the regulations immediately be released into the lake. However, it is apparent from the size composition that release of these small crayfish was rather incomplete. In 1983, trap mesh size was increased from 17.5 mm to 21 mm to reduce the fraction of undersized crayfish in the trap catches, yet no effects of this increased mesh size on crayfish size distribution were observed. The legal season has been reduced three times during the study period. In 1983, the closing date was changed from 31 December to 15 September. In 1989 the legal season was further reduced to two weeks and finally in 1995 to 10 days. This reduced total trap effort by 45%. The shorter season allow many crayfish to moult twice instead of once between seasons and the fraction of large crayfish has thus increased and so has the catch per trap night. Canadian pondweed has established dense annual stands and thus has made large parts of the shallow areas unsuitable for crayfish, causing an overall decrease in crayfish population size and production.

Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

International Nuclear Information System (INIS)

Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

1979-01-01

The White Oak floodplain was contaminated with several radionuclides, including 239 Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using 237 Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the 237 Pu was associated with the body tissues. Complementary data for 237 Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of 239 Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average 239 Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of 239 Pu in the soil in which they burrow and was found to be eight orders of magnitude less

Investigation of plutonium concentration and distribution in burrowing crayfish from the White Oak Creek floodplain

Energy Technology Data Exchange (ETDEWEB)

Delaney, M.S.; Dahlman, R.C.; Craig, R.B.

1979-01-01

The White Oak floodplain was contaminated with several radionuclides, including /sup 239/Pu, during the Manhattan Project in 1944. Plutonium distribution in the soil is nonhomogeneous. An investigation was conducted to deterine Pu accumulation in a resident animal population. Crayfish were chosen because they complete their life-cycle within the contaminated environment, they directly contact contaminated muds, and they function in a food chain of significance to man. Two major conclusions of the research were that Pu concentrations in contaminated crayfish typically exceed those of control crayfish by two orders of magnitude and that if an incident were to occur in which a standard man ingested the soft tissues of ten crayfish from the floodplain, an insignificant whole body dose would accrue over the subsequent 50 years of life. The digestive tract of contaminated crayfish contained 21 to 33% of the Pu body burden, soft tissues contained 11 to 31% of the Pu body burden, and 48 to 62% of the Pu body burden of contaminated crayfish was associated with the carapace. Therefore, at a molt a large proportion of its accumulated Pu is deposited in the environment. A supplementary laboratory investigation using /sup 237/Pu included a chronic Pu uptake study by uncontaminated crayfish. In these crayfish, from 64 to 82% of the /sup 237/Pu was associated with the body tissues. Complementary data for /sup 237/Pu associated with the carapace ranged from 18 to 37% of the distribution. An inventory of /sup 239/Pu in crayfish at two sites on the floodplain was calculated by multiplying the estimated biomass of the crayfish by their average /sup 239/Pu concentration. This evaluation of Pu associated with the crayfish population was compared to an inventory of /sup 239/Pu in the soil in which they burrow and was found to be eight orders of magnitude less.

A new ostracod (Entocytheridae, Notocytherinae) on New Guinea crayfish1)

NARCIS (Netherlands)

Hart, D.G.; Hart, C.W.

1970-01-01

In 1967 we examined the crayfish collections in the Rijksmuseum van Natuurlijke Historie, Leiden, to determine if the crayfishes collected in New Guinea in 1954 by Dr. L. B. Holthuis, Dr. L. D. Brongersma, and Dr. M. Boeseman (Boeseman, 1963) were hosts to commensal ostracods. Of the collections

Incomes, Attitudes, and Occurrences of Invasive Species: An Application to Signal Crayfish in Sweden

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Gren, Ing-Marie; Campos, Monica; Edsman, Lennart; Bohman, Patrik

2009-02-01

This article analyzes and carries out an econometric test of the explanatory power of economic and attitude variables for occurrences of the nonnative signal crayfish in Swedish waters. Signal crayfish are a carrier of plague which threatens the native noble crayfish with extinction. Crayfish are associated with recreational and cultural traditions in Sweden, which may run against environmental preferences for preserving native species. Econometric analysis is carried out using panel data at the municipality level with economic factors and attitudes as explanatory variables, which are derived from a simple dynamic harvesting model. A log-normal model is used for the regression analysis, and the results indicate significant impacts on occurrences of waters with signal crayfish of changes in both economic and attitude variables. Variables reflecting environmental and recreational preferences have unexpected signs, where the former variable has a positive and the latter a negative impact on occurrences of waters with signal crayfish. These effects are, however, counteracted by their respective interaction effect with income.

STUDIES ON THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES ASSOCIATED WITH MUDDY HABITATS

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HOLDICH D. M.

2006-01-01

Full Text Available The white-clawed crayfish, Austropotamobius pallipes, is usually found associated with stony habitats containing obvious refuges in the form of gaps between and under rocks, macrophytes and marginal tree roots, particularly in streams and lakes with clear water and little marginal mud. If the banks are composed of suitable material, then they may also construct and live in burrows. However, the white-clawed crayfish is also found to be abundant in streams, rivers, canals and millraces with deep, anoxic mud and with very little aquatic vegetation. Foraging on the surface of mud may be the only way they can obtain sufficient food in the form of macroinvertebrates and decaying plant matter. Where do crayfish live in this restricted habitat? Dewatering such waterways for essential engineering works, such as desilting, bridge and weir repairs, bank reinforcements, and maintenance of outfalls can provide an excellent opportunity to study the available habitat and the crayfish populations, in addition good estimates of population size and age class distribution can be obtained, although, as with other methods, juveniles tend to be underrepresented. A number of case studies will be given to illustrate the fact that white-clawed crayfish are able to colonize muddy habitats in some numbers. The value of retaining trees with their roots hanging into waterways as a refuge for both crayfish and small fish is highlighted.

Are the effects of an invasive crayfish on lake littoral macroinvertebrate communities consistent over time?

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Ruokonen T. J.

2016-01-01

Full Text Available Management of invasive species requires assessment of their effects on recipient ecosystems. However, impact assessment of invasive species commonly lacks a long-term perspective which can potentially lead to false conclusions. We examined the effects of the invasive signal crayfish (Pacifastacus leniusculus Dana on the stony littoral macroinvertebrate communities of a large boreal lake and assessed the extent to which the patterns observed in previous short-term studies were stable over time. We used temporal macroinvertebrate data collected in five consecutive years from a site with a well-established crayfish population, a site with no crayfish and a site where crayfish had been recently introduced. Our results revealed that signal crayfish had temporally rather consistent negative effects on the benthic macroinvertebrate assemblages but that the effects might be limited to certain taxa, in particular Gastropoda and Coleoptera. We also observed increases in Gastropoda density and taxa richness following a decline in crayfish density, indicating that the recovery of invertebrate assemblages might be fast. Hence, negative effects on benthic macroinvertebrates can likely be minimized by effective control of the signal crayfish population.

Crustacean hyperglycemic hormone (cHH as a modulator of aggression in crustacean decapods.

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Laura Aquiloni

Full Text Available Biogenic amines, particularly serotonin, are recognised to play an important role in controlling the aggression of invertebrates, whereas the effect of neurohormones is still underexplored. The crustacean Hyperglycemic Hormone (cHH is a multifunctional member of the eyestalk neuropeptide family. We expect that this neuropeptide influences aggression either directly, by controlling its expression, or indirectly, by mobilizing the energetic stores needed for the increased activity of an animal. Our study aims at testing such an influence and the possible reversion of hierarchies in the red swamp crayfish, Procambarus clarkii, as a model organism. Three types of pairs of similarly sized males were formed: (1 'control pairs' (CP, n = 8: both individuals were injected with a phosphate saline solution (PBS; (2 'reinforced pairs' (RP, n = 9: the alpha alone was injected with native cHH, and the beta with PBS; (3 'inverted pairs' (IP, n = 9: the opposite of (2. We found that, independently of the crayfish's prior social experience, cHH injections induced (i the expression of dominance behaviour, (ii higher glycemic levels, and (iii lower time spent motionless. In CP and RP, fight intensity decreased with the establishment of dominance. On the contrary, in IP, betas became increasingly likely to initiate and escalate fights and, consequently, increased their dominance till a temporary reversal of the hierarchy. Our results demonstrate, for the first time, that, similarly to serotonin, cHH enhances individual aggression, up to reverse, although transitorily, the hierarchical rank. New research perspectives are thus opened in our intriguing effort of understanding the role of cHH in the modulation of agonistic behaviour in crustaceans.

ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

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In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

Effects of mining-derived metals on riffle-dwelling crayfish in southwestern Missouri and southeastern Kansas, USA

Science.gov (United States)

Allert, Ann L.; DiStefano, Robert J.; Schmitt, Christopher J.; Fairchild, James F.; Brumbaugh, William G.

2012-01-01

Riffle-dwelling crayfish populations were sampled at 16 sites in 4 tributaries of the Spring River located within the Tri-State Mining District in southwest Missouri. Crayfish density, physical habitat quality, and water quality were examined at each site to assess the ecological effects of mining-derived metals on crayfish. Metals (lead, zinc, and cadmium) were analyzed in samples of surface water, sediment, detritus, and whole crayfish. Sites were classified a posteriori into reference, mining, and downstream sites primarily based on metal concentrations in the materials analyzed. Three species of crayfish (Orconectes neglectus neglectus, O. macrus, and O. virilis) were collected during the study; however, only O. n. neglectus was collected at all sites. Mean crayfish densities were significantly lower at mining sites than at reference sites. Mean concentrations of metals were significantly correlated among the materials analyzed and were significantly greater at mining and downstream sites than at reference sites. Principal component analyses showed a separation of sites due to an inverse relationship among crayfish density, metals concentrations, and physical habitat quality variables. Sediment probable-effects quotients and surface-water toxic unit scores were significantly correlated; both indicated risk of toxicity to aquatic biota at several sites. Metals concentrations in whole crayfish at several sites exceeded concentrations known to be toxic to carnivorous wildlife. Mining-derived metals have the potential to impair ecosystem function through decreased organic matter processing and nutrient cycling in streams due to decreased crayfish densities.

WHITE-CLAWED CRAYFISH IN MUDDY HABITATS: MONITORING THE POPULATION IN THE RIVER IVEL, BEDFORDSHIRE, UK

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PEAY S.

2006-01-01

Full Text Available White-clawed crayfish Austropotamobius pallipes are usually associated with stony substrates, tree roots, or refuges in submerged banks. The River Ivel has the last known population of white-clawed crayfish in Bedfordshire. Prior to 2005, much of the bed comprised uniform silt, plus leaf-litter. Stands of reedmace Typha latifolia and other emergent vegetation were localised in less shaded areas. Initial survey results suggested a population at low abundance. A low-cost monitoring strategy was started in 2001 and continued three times a year to 2005, using engineering bricks, which offer artificial refuges. Crayfish are counted when bricks are lifted periodically. De-silting of c. 430 m river was carried out in February 2005, to improve habitat and to maintain the flood capacity in the channel upstream of a mill weir. Additional bricks were deployed a few weeks in advance of de-silting, then bricks and crayfish were lifted prior to dredging and were returned the next day. Starting upstream, soft, wet mud was dredged out, placed on the bank and searched manually for crayfish. Banks, tree roots and shallow margins were left undisturbed. In all, 4,142 crayfish were found in dredgings from a 430 m length of the mid channel. Crayfish were strongly associated with emergent vegetation, but many were present below the surface of the silt. Crayfish released in the dredged channel immediately burrowed into the silt retained on the channel margins. Monitoring after dredging showed no change in abundance in the main area with in-bank refuges and lots of bricks, but there was an increase in occupancy of bricks in an area where most crayfish had been in emergent vegetation.

CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

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REYNOLDS J. D.

2001-04-01

Full Text Available The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet occur in these systems, Dreissena has not yet colonized sites with large crayfish populations. In laboratory experiments crayfish of both sexes ranging in size from 32-48 mm carapace length (CL were offered zebra mussels in 7 size classes spanning a range from 3-17 mm total length. Crayfish fed most on small mussels, although there was some correlation between size of crayfish and largest mussels attacked. When eaten mussels were not replaced, crayfish shifted to larger sizes. In the presence of alternative prey, experienced crayfish ate mussels and alternative foods in similar amounts while those who had never encountered zebra mussels nearly always chose the alternative foods first. The possibility of crayfish exerting significant controlling impacts on expanding mussel populations is discussed.

Phylogenetic species delimitation for crayfishes of the genus Pacifastacus.

Science.gov (United States)

Larson, Eric R; Castelin, Magalie; Williams, Bronwyn W; Olden, Julian D; Abbott, Cathryn L

2016-01-01

Molecular genetic approaches are playing an increasing role in conservation science by identifying biodiversity that may not be evident by morphology-based taxonomy and systematics. So-called cryptic species are particularly prevalent in freshwater environments, where isolation of dispersal-limited species, such as crayfishes, within dendritic river networks often gives rise to high intra- and inter-specific genetic divergence. We apply here a multi-gene molecular approach to investigate relationships among extant species of the crayfish genus Pacifastacus, representing the first comprehensive phylogenetic study of this taxonomic group. Importantly, Pacifastacus includes both the widely invasive signal crayfish Pacifastacus leniusculus, as well as several species of conservation concern like the Shasta crayfish Pacifastacus fortis. Our analysis used 83 individuals sampled across the four extant Pacifastacus species (omitting the extinct Pacifastacus nigrescens), representing the known taxonomic diversity and geographic distributions within this genus as comprehensively as possible. We reconstructed phylogenetic trees from mitochondrial (16S, COI) and nuclear genes (GAPDH), both separately and using a combined or concatenated dataset, and performed several species delimitation analyses (PTP, ABGD, GMYC) on the COI phylogeny to propose Primary Species Hypotheses (PSHs) within the genus. All phylogenies recovered the genus Pacifastacus as monophyletic, within which we identified a range of six to 21 PSHs; more abundant PSHs delimitations from GMYC and ABGD were always nested within PSHs delimited by the more conservative PTP method. Pacifastacus leniusculus included the majority of PSHs and was not monophyletic relative to the other Pacifastacus species considered. Several of these highly distinct P. leniusculus PSHs likely require urgent conservation attention. Our results identify research needs and conservation priorities for Pacifastacus crayfishes in western

Mitochondrial cytochrome oxidase I gene analysis indicates a restricted genetic background in Finnish noble crayfish (Astacus astacus stocks

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Makkonen J.

2015-01-01

Full Text Available The IUCN Red List indexes the noble crayfish (Astacus astacus as vulnerable, with a declining population trend. The main threats to the species are the crayfish plague caused by the oomycete Aphanomyces astaci and the introduced North American crayfish that act as the carriers of this disease. In Finland, the noble crayfish is considered as a native species, which original distribution area covers the southern part of the country, but the species distribution has been dispersed to cover almost the whole country. The aim of this study was to survey the genetic diversity among the Finnish noble crayfish populations. The mitochondrial cytochrome oxidase I (COI-gene was sequenced from 742 individuals representing 59 populations from Finland and Estonia. As a result, only a single haplotype was found. Based on these results, the genetic diversity of noble crayfish in its Northern distribution range is remarkably low. The observed lack of variation can result from several mechanisms including small size of the founder population and the intense spreading of the species by manmade stockings. The restricted diversity can also be caused by eradication of the original populations due to crayfish plague epidemics and spreading of the invasive crayfish species carrying the crayfish plague. It is also possible that all contemporary Finnish noble crayfish populations originate from stockings with no variation in respect to COI-gene.

The combined use of chemical and biochemical markers to assess water quality in two low-stream rivers (NE Spain)

International Nuclear Information System (INIS)

Fernandes, Denise; Potrykus, Joanna; Morsiani, Cinzia; Raldua, Demetrio; Lavado, Ramon; Porte, Cinta

2002-01-01

Carps (Cyprinus carpio) and red swamp crayfish (Procambarus clarkii) were sampled from two low- stream Mediterranean rivers (Anoia and Cardener) receiving extensive urban and industrial waste water discharges. Tissue residues of selected pollutants (organo chlorinated compounds, polycyclic aromatic hydrocarbons (PAHs)) were determined in conjunction with different biochemical responses (cytochrome P450, phase II enzymes) with the aim of investigating whether resident organisms were responsive to changes in water quality. Biota inhabiting those rivers were highly exposed to complex mixtures of polychlorobiphenyls and dichlorodiphenyltrichloroethanes (up to 9 ng/g w.w.) and PAHs (up to 6097 ng/g of hydroxylated PAHs in bile), the highest residues being observed in carps from Cardener. This has a reflection n 7-ethoxyresorufin O-deethylase (EROD) activity; that in carps from ardener ranged between 350 and 550 pmol/min/mg protein, whereas in carps from Anoia ranged between was 90 and 250 pmol/min/mg protein. The highest activity recorded was downstream of the sewage treatment plants in both rivers. Phase II enzymes were less sensitive to pollutant exposure than EROD; nonetheless, both glutathione S-transferase and UDP-glucuronyl transferase ere higher in carps from Cardener. The results support the usefulness of the combined use of chemical and biochemical responses to assess and diagnose pollution in highly stressed ecosystems

REVIEW OF THE NATIONAL RESTOCKING PROGRAMME “ACTIVE PROTECTION OF NATIVE CRAYFISH IN POLAND” 1999-2001

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ŠMIETANA P.

2004-01-01

Full Text Available After the first spread of crayfish plague (aphanomycosis at the end of the nineteenth century, the formerly abundant populations of native crayfish in Poland declined drastically. Analysis of historical data on the occurrence and distribution of crayfish in Poland led to the conclusion that without human intervention the native crayfish species would be at high risk of being made extinct. The largest programme concerning crayfish monitoring and restocking in Poland was “Active protection of native crayfish in Poland” conducted by the Inland Fisheries Institute, the Department of Ecology, University of Szczecin, the Department of Zoology, Warsaw Agricultural University and the University of Warmia and Mazury that was funded by the EkoFundusz Foundation and Inland Fisheries Institute in 1999-2001. One of the main objectives and results of this programme was the determination of indigenous crayfish distribution in Poland (mainly Astacus astacus and Astacus leptodactylus and the restocking of suitable habitats with indigenous crayfish. The densest populations (> 2 500 adult individuals per hectare were used as a source of restocking material. Restocking was performed in 54 water bodies using a total of 45 200 individuals of A. astacus and 9 800 of A. leptodactylus. Between 2001-2002, the success of the restocking programme was monitored. According to the results obtained so far, the restocking exercise has been successful in at least 60.8% of the cases.

Partition of ruthenium-106 between the fresh water environment and crayfish

International Nuclear Information System (INIS)

Berg, G.G.; Ginsberg, E.

1976-01-01

Crayfish of two species, Orconectes obscurus and Cambarus robustus, were identified in West Valley, New York, in streams contaminated with radioactive wastes. 106 Ru accounted for over 90% of the gamma radioactivity in specimens collected in 1972, and had higher concentrations in the crayfish than in fish from that site. Crayfish are suggested as indicator organisms for 106 Ru. In subsequent aquarium experiments, crayfish exposed to water labeled with inorganic complexes of 106 Ru concentrated the dissolved ruthenium an average of 9 x and accumulated 50% of the equilibrium body burden in approximately 10 hr, with the bulk of the isotope bound at the surface of the exoskeleton. If food was also exposed to the labeled water, uptake was faster and high concentrations were found in the digestive gland, which showed concentration factors in excess of 25 x. Releases were slower and bimodal, with approximately 10% of body burden remaining after 1 or 2 months in repeated changes of water. Data describe the partition of 106 Ru to colloidal aggregates and organically-bound sediments, and its availability for bioconcentration. (author)

Accumulation of Heavy Metals in Crayfish and Fish from Selected Czech Reservoirs

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Iryna Kuklina

2014-01-01

Full Text Available To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše and one contaminated site (Darkovské moře in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr, while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb. The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys.

KEYNOTE PRESENTATION AND ROUNDTABLE SESSION 4. CRAYFISH PATHOLOGY IN EUROPE:PAST, PRESENT AND A PROGRAMME FOR THE FUTURE

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EDGERTON B. F.

2004-01-01

Full Text Available The devastating affects of disease on European freshwater crayfish are well known as epizootics in wild populations have occurred throughout much of Europe since the mid XVIIIe s. After protracted and rigorous debate, the cause of the disease named crayfish plague was proved to be the fungus Aphanomyces astaci in 1934. In the last 70 years, much of the research conducted in the field of crayfish pathology has concentrated on fungi, especially improving diagnostic techniques for A. astaci. Similarly, diagnostic responses to epizootics in European crayfish have concentrated almost entirely on fungal isolation and/or identification. On the other hand, viruses have proved to be the most important pathogens in the growing global crustacean aquaculture and fishery industries. Rickettsia-like organisms (RLO are also important. Critically, diagnostic techniques necessary to detect the full range of potential pathogens of crayfish are rarely utilized in the field of crayfish pathology in Europe. Histopathological analysis, required for the diagnosis of infections by viruses and RLOs, is absent from most European studies. Epizootics unrelated to A. astaci in European crayfish and epizootics in introduced American crayfish species highlight the inadequate current state of knowledge in the field. Presently, the field is ill-equipped to determine the cause(s of these epizootics. Moreover, crayfish conservation strategies may be undermined and even detrimental to the longterm goals; eg., stocking programs may spread undetected pathogens. Therefore, critical limitations in the field of crayfish pathology have major repercussions in management of freshwater crayfish. Guiding principles and a concept for a trans-European Community research and education program were developed to address this serious issue and are presented herein.

Toxicological studies of cadmium and zinc on the crayfish Orconectes virilis

International Nuclear Information System (INIS)

Mirenda, R.J.

1985-01-01

The acute toxicities of cadmium and of zinc to the crayfish Oronectes virilis were determined. Adult, intermolt crayfish were exposed to a series of concentrations of either cadmium or zinc for a two week period. Cadmium was found to be a cumulative poison to the crayfish; LC50 values decreased from 6.1 mg Cd/I for 96 hours to 0.7 mg Cd/I for two weeks. An incipient LC50 was also estimated to be 0.0604 mg Cd/I. Zinc was found to have a relatively low toxicity to O. virilis under the present exposure conditions. Whole animal and tissue analyses for cadmium or zinc were performed on the crayfish used in the acute toxicity tests. Whole animals concentrations both for cadmium and for zinc exhibited a linear relationship to exposure concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations (r = 0.85 and 0.87, respectively). The gills had the highest concentrations of cadmium and zinc, and displayed a linear relationship to exposure concentrations (r = 0.82 and 0.87 respectively). The hepatopancreas displayed a plateau in metal concentrations and is probably the main storage site for both metals in the crayfish. The relationship of cadmium concentration to exposure concentration in the antennal glands also showed linearity (r = 0.65), while zinc levels reached a steady state level. All the remaining tissues analyzed exhibited a plateau in metal concentration

A Trial of Natural Habitat Enclosure Traps as a Sampling Tool for Juvenile Crayfish

OpenAIRE

Fjälling, Arne; Engdahl, Fredrik; Edsman, Lennart; Bohman, Patrik; Sandström, Alfred

2013-01-01

Recruitment is a vital factor in the assessment, management and population dynamics of decapods. Since the juvenile stages of crayfish often prefer heterogeneous habitats, sampling with quantitative and reproducible methods have so far been challenging. We evaluate a new quantitative sampling method for juvenile crayfish; the enclosure trap. A field test was carried out during two consecutive years on a population of signal crayfish, Pacifastacus leniusculus, in littoral areas of Swedish Lake...

Diet of the crayfish Paranephrops zealandicus in bush and pasture streams : insights from stable isotopes and stomach analysis

International Nuclear Information System (INIS)

Hollows, J.W.; Townsend, C.R.; Collier, K.J.

2002-01-01

Crayfish (Paranephrops zealandicus White) stomachs from streams in both native bush (mainly tree leaves and dicotyledonous seeds) and exotic pasture settings (mainly grass stems and monocotyledonous seeds) were dominated by allochthonous material. More detritus occurred in stomachs in autumn-winter than in spring-summer, but quantities were similar in crayfish from native bush and pasture streams. The stomachs of larger crayfish contained a significantly greater proportion of detritus than smaller individuals. Aquatic invertebrates were the second most abundant dietary category by volume, with highest values in winter, but there were no significant differences between land uses or crayfish size classes. A wide range of invertebrates was eaten by crayfish, with mayfly nymphs, chironomid larvae, and snails predominating. The latter were numerically more prominent in crayfish from bush than pasture streams. Terrestrial invertebrates were recorded from 4% of stomachs, but there were no significant differences in relation to land use, season, or crayfish size class. Despite aquatic invertebrates making up 13 C and perhaps of microfloral origin, seems to be an important energy source for crayfish in both stream types. (author). 52 refs., 5 figs., 2 tabs

Enzymatic production of N-acetyl-d-glucosamine from crayfish shell wastes pretreated via high pressure homogenization.

Science.gov (United States)

Wei, Guoguang; Zhang, Alei; Chen, Kequan; Ouyang, Pingkai

2017-09-01

This study presents an efficient pretreatment of crayfish shell using high pressure homogenization that enables N-acetyl-d-glucosamine (GlcNAc) production by chitinase. Firstly, the chitinase from Serratia proteamaculans NJ303 was screened for its ability to degrade crayfish shell and produce GlcNAc as the sole product. Secondly, high pressure homogenization, which caused the crayfish shell to adopt a fluffy netted structure that was characterized by Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), was evaluated as the best pretreatment method. In addition, the optimal conditions of high pressure homogenization of crayfish shell were determined to be five cycles at a pressure of 400bar, which achieved a yield of 3.9g/L of GlcNAc from 25g/L of crayfish shell in a batch enzymatic reaction over 1.5h. The results showed high pressure homogenization might be an efficient method for direct utilization of crayfish shell for enzymatic production of GlcNAc. Copyright © 2017 Elsevier Ltd. All rights reserved.

A REVIEW OF INTERNATIONAL BIOSECURITY POLICY DEVELOPMENT IN RELATION TO MOVEMENTS OF FRESHWATER CRAYFISH

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EDGERTON B. F.

2002-07-01

Full Text Available Freshwater crayfish are frequently traded, both alive (for human consumption or for fisheries/aquaculture stocking and as processed products (e.g. fresh or frozen, cooked or uncooked. As the experience in Europe with crayfish plague has shown, there can be significant risks of translocating pathogens with such trade. Such risks can be assessed in an import risk analysis process. This paper will concentrate on describing the principles of import risk analysis (IRA with particular reference to freshwater crayfish.

Effects of Different Social and Environmental Conditions on Established Dominance Relationships in Crayfish.

Science.gov (United States)

Herberholz, Jens; Swierzbinski, Matthew E; Birke, Juliane M

2016-04-01

Like most social animals, crayfish readily form dominance relationships and linear social hierarchies when competing for limited resources. Competition often entails dyadic aggressive interactions, from which one animal emerges as the dominant and one as the subordinate. Once dominance relationships are formed, they typically remain stable for extended periods of time; thus, access to future resources is divided unequally among conspecifics. We previously showed that firmly established dominance relationships in juvenile crayfish can be disrupted by briefly adding a larger conspecific to the original pair. This finding suggested that the stability of social relationships in crayfish was highly context-dependent and more transient than previously assumed. We now report results that further identify the mechanisms underlying the destabilization of crayfish dominance relationships. We found that rank orders remained stable when conspecifics of smaller or equal size were added to the original pair, suggesting that both dominant and subordinate must be defeated by a larger crayfish in order to destabilize dominance relationships. We also found that dominance relationships remained stable when both members of the original pair were defeated by larger conspecifics in the absence of their original opponent. This showed that dominance relationships are not destabilized unless both animals experience defeat together. Lastly, we found that dominance relationships of pairs were successfully disrupted by larger intruders, although with reduced magnitude, after all chemical cues associated with earlier agonistic experiences were eliminated. These findings provide important new insights into the contextual features that regulate the stability of social dominance relationships in crayfish and probably in other species as well. © 2016 Marine Biological Laboratory.

A SURVEY OF THE WHITE-CLAWED CRAYFISH,AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET, AND OF WATERQUALITY IN TWO CATCHMENTS OF EASTERN IRELAND.

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DEMERS A.

2002-07-01

Full Text Available The white-clawed crayfish, Austropotamobius pallipes (Lereboullet, is the only crayfish species found in Ireland. Because of the prohibition on importation of exotic species of crayfish onto the island and of its relatively clean rivers up to now, Ireland has kept an abundant population of crayfish. A survey was conducted in the catchments of the Liffey and Boyne rivers, in eastern Ireland to assess water quality and to sample crayfish populations. The aim of the study was to evaluate the water quality requirements of the white-clawed crayfish in Ireland. Baited traps and nets were used to sample crayfish while water quality was measured with biological indices calculated from samples of macroinvertebrates. Distribution of this crayfish species is patchy in the Liffey catchment and seems to be related to factors such as soil types and water quality. They were not found in the downstream part of the river Liffey possibly due to poor water quality. In the Boyne catchment, no crayfish were found in most of the catchment. They were only present in the Kells Blackwater subcatchment. This may be due to an earlier outbreak of the fungal plague caused by Aphanomyces astaci. The disease was discovered in lakes at the top of some of the tributaries of the Boyne in 1987 and it probably spread from there through the whole catchment.

Increasing Potential Risk of a Global Aquatic Invader in Europe in Contrast to Other Continents under Future Climate Change

Science.gov (United States)

Liu, Xuan; Guo, Zhongwei; Ke, Zunwei; Wang, Supen; Li, Yiming

2011-01-01

Background Anthropogenically-induced climate change can alter the current climatic habitat of non-native species and can have complex effects on potentially invasive species. Predictions of the potential distributions of invasive species under climate change will provide critical information for future conservation and management strategies. Aquatic ecosystems are particularly vulnerable to invasive species and climate change, but the effect of climate change on invasive species distributions has been rather neglected, especially for notorious global invaders. Methodology/Principal Findings We used ecological niche models (ENMs) to assess the risks and opportunities that climate change presents for the red swamp crayfish (Procambarus clarkii), which is a worldwide aquatic invasive species. Linking the factors of climate, topography, habitat and human influence, we developed predictive models incorporating both native and non-native distribution data of the crayfish to identify present areas of potential distribution and project the effects of future climate change based on a consensus-forecast approach combining the CCCMA and HADCM3 climate models under two emission scenarios (A2a and B2a) by 2050. The minimum temperature from the coldest month, the human footprint and precipitation of the driest quarter contributed most to the species distribution models. Under both the A2a and B2a scenarios, P. clarkii shifted to higher latitudes in continents of both the northern and southern hemispheres. However, the effect of climate change varied considerately among continents with an expanding potential in Europe and contracting changes in others. Conclusions/Significance Our findings are the first to predict the impact of climate change on the future distribution of a globally invasive aquatic species. We confirmed the complexities of the likely effects of climate change on the potential distribution of globally invasive species, and it is extremely important to develop

Characteristics of mangrove swamps managed for mosquito control in eastern Florida, USA

Science.gov (United States)

Middleton, B.; Devlin, D.; Proffitt, E.; McKee, K.; Cretini, K.F.

2008-01-01

Manipulations of the vegetation and hydrology of wetlands for mosquito control are common worldwide, but these modifications may affect vital ecosystem processes. To control mosquitoes in mangrove swamps in eastern Florida, managers have used rotational impoundment management (RIM) as an alternative to the worldwide practice of mosquito ditching. Levees surround RIM swamps, and water is pumped into the impoundment during the summer, a season when natural swamps have low water levels. In the New World, these mosquito-managed swamps resemble the mixed basin type of mangrove swamp (based on PCA analysis). An assessment was made of RIM, natural (control), and breached-RIM (restored) swamps in eastern Florida to compare their structural complexities, soil development, and resistance to invasion. Regarding structural complexity, dominant species composition differed between these swamps; the red mangrove Rhizophora mangle occurred at a higher relative density in RIM and breached-RIM swamps, and the black mangrove Avicennia germinans had a higher relative density in natural swamps. Tree density and canopy cover were higher and tree height lower in RIM swamps than in natural and breached-RIM swamps. Soil organic matter in RIM swamps was twice that in natural or breached-RIM swamps. RIM swamps had a lower resistance to invasion by the Brazilian pepper tree Schinus terebinthifolius, which is likely attributable to the lower porewater salinity in RIM swamps. These characteristics may reflect differences in important ecosystem processes (primary production, trophic structure, nutrient cycling, decomposition). Comparative assessments of managed wetlands are vital for land managers, so that they can make informed decisions compatible with conservation objectives. ?? Inter-Research 2008.

Spatial dynamics of the noble crayfish (Astacus astacus, L. in the Paklenica National Park

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G.I.V. Klobucar

2008-07-01

Full Text Available The aim of this work was to analyse the spatial dynamics of a noble crayfish population inhabiting the Velika Paklenica Stream (Paklenica National Park, Croatia. The study was conducted in July 2000, and between March and September 2002. Crayfish were trapped by baited LiNi traps and hand-made traps at two localities over 25 nights. We recorded the precise position of the captured crayfish, their sex, and total length. Crayfish were individually marked and then released back into the stream at the same spot where they were caught. Spatial analyses included determination of movement direction, distribution type, home range, total distance travelled, and mean daily movement. A mean home range of approximately 19 m was calculated. No difference in home range between the sexes was found. There was a large individual variation in the extent of movement without any effect of sex or size.

Utilization of Swamp Forages from South Kalimantan on Local Goat Performances

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T. Rostini

2014-04-01

Full Text Available Forages in swamp area consist of grass and legumes that have good productivity and nutrient quality. This research was aimed to evaluate the potency of swamp forage on digestibility and performance of goats. There were 24 local male goats aged 10-12 months with initial body weight of 13.10±1.55 kg, allocated into 6 treatments. Those were control (R0: 60% grass and 40% legumes; (R1: 60% swamp forages and 40% concentrate; (R2: 100% swamp forages; (R3: 100% swamp forage hay; (R4: 100% swamp forage silage; (R5: 100% haylage swamp forages. Results showed that silage treatment significantly increased (P<0.05 consumption and digestibility. Swamp forages could be utilized well by preservation (silage, hay, and haylage. Ensilage of swamp forages increased protein content from 13.72% to 14.02%, protein intake (74.62 g/d, dry matter intake (532.11 g/d, nitrogen free extract intake (257.39 g/d, with total body weight gain (3.5 kg in eight weeks and average daily gain (62.60 g/d. It is concluded that ensilage of swamp forages (R4 is very potential to be utilized as forage source for ruminants such as goats.

Effects of historical lead–zinc mining on riffle-dwelling benthic fish and crayfish in the Big River of southeastern Missouri, USA

Science.gov (United States)

Allert, A.L.; DiStefano, R.J.; Fairchild, J.F.; Schmitt, C.J.; McKee, M.J.; Girondo, J.A.; Brumbaugh, W.G.; May, T.W.

2013-01-01

The Big River (BGR) drains much of the Old Lead Belt mining district (OLB) in southeastern Missouri, USA, which was historically among the largest producers of lead–zinc (Pb–Zn) ore in the world. We sampled benthic fish and crayfish in riffle habitats at eight sites in the BGR and conducted 56-day in situ exposures to the woodland crayfish (Orconectes hylas) and golden crayfish (Orconectes luteus) in cages at four sites affected to differing degrees by mining. Densities of fish and crayfish, physical habitat and water quality, and the survival and growth of caged crayfish were examined at sites with no known upstream mining activities (i.e., reference sites) and at sites downstream of mining areas (i.e., mining and downstream sites). Lead, zinc, and cadmium were analyzed in surface and pore water, sediment, detritus, fish, crayfish, and other benthic macro-invertebrates. Metals concentrations in all materials analyzed were greater at mining and downstream sites than at reference sites. Ten species of fish and four species of crayfish were collected. Fish and crayfish densities were significantly greater at reference than mining or downstream sites, and densities were greater at downstream than mining sites. Survival of caged crayfish was significantly lower at mining sites than reference sites; downstream sites were not tested. Chronic toxic-unit scores and sediment probable effects quotients indicated significant risk of toxicity to fish and crayfish, and metals concentrations in crayfish were sufficiently high to represent a risk to wildlife at mining and downstream sites. Collectively, the results provided direct evidence that metals associated with historical mining activities in the OLB continue to affect aquatic life in the BGR.

First record of the invasive Australian redclaw crayfish Cherax quadricarinatus (von Martens, 1868 in the Crocodile River, Kruger National Park, South Africa

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Robin M. Petersen

2017-03-01

Full Text Available The redclaw crayfish Cherax quadricarinatus (von Martens, 1868, a robust freshwater crayfish native to Australia and Papua New Guinea, has now been recorded from the Kruger National Park (KNP. Previously absent from the Crocodile River, SAN Parks received a report in February 2016 of redclaw crayfish below the Van Graan Dam on the border of the KNP. Here, we provide evidence of the presence of redclaw crayfish in the Crocodile River. A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the KNP and the Komati Catchment. The negative impacts of global crayfish introductions justify efforts to discourage further introductions and prevent their secondary spread. Conservation implications: A better understanding of the redclaw crayfish distribution, habitat preferences, rate of spread and impacts on the local aquatic ecosystems in the Crocodile River is urgently required to develop mitigation strategies that minimise the spread of this invasive crayfish in the Kruger National Park and the Komati Catchment.

Distribution of crayfish species in Hungarian waters

NARCIS (Netherlands)

Mercédesz, Ludányi; Peeters, E.T.H.M.; Kiss, B.; Roessink, I.

2016-01-01

Three native crayfish species, i.e.~Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, occur in Hungary. Lately, however, non-indigenous crustaceans have also invaded the country Their most recent distribution and impact on the occurrences of the native species is not clear.

A comparison of two gears for quantifying abundance of lotic-dwelling crayfish

Science.gov (United States)

Williams, Kristi; Brewer, Shannon K.; Ellersieck, Mark R.

2014-01-01

Crayfish (saddlebacked crayfish, Orconectes medius) catch was compared using a kick seine applied two different ways with a 1-m2 quadrat sampler (with known efficiency and bias in riffles) from three small streams in the Missouri Ozarks. Triplicate samples (one of each technique) were taken from two creeks and one headwater stream (n=69 sites) over a two-year period. General linear mixed models showed the number of crayfish collected using the quadrat sampler was greater than the number collected using either of the two seine techniques. However, there was no significant interaction with gear suggesting year, stream size, and channel unit type did not relate to different catches of crayfish by gear type. Variation in catch among gears was similar, as was the proportion of young-of-year individuals across samples taken with different gears or techniques. Negative binomial linear regression provided the appropriate relation between the gears which allows correction factors to be applied, if necessary, to relate catches by the kick seine to those of the quadrat sampler. The kick seine appears to be a reasonable substitute to the quadrat sampler in these shallow streams, with the advantage of ease of use and shorter time required per sample.

Temporal variation in the prevalence of the crayfish plague pathogen, Aphanomyces astaci, in three Czech spiny-cheek crayfish populations

Czech Academy of Sciences Publication Activity Database

Matasová, K.; Kozubíková, E.; Svoboda, J.; Jarošík, Vojtěch; Petrusek, A.

-, č. 401 (2011), s. 1-9 ISSN 1961-9502 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : crayfish plague * molecular methosd * dominance Subject RIV: EH - Ecology, Behaviour Impact factor: 1.520, year: 2011

Effects of pond draining on biodiversity and water quality of farm ponds.

Science.gov (United States)

Usio, Nisikawa; Imada, Miho; Nakagawa, Megumi; Akasaka, Munemitsu; Takamura, Noriko

2013-12-01

Farm ponds have high conservation value because they contribute significantly to regional biodiversity and ecosystem services. In Japan pond draining is a traditional management method that is widely believed to improve water quality and eradicate invasive fish. In addition, fishing by means of pond draining has significant cultural value for local people, serving as a social event. However, there is a widespread belief that pond draining reduces freshwater biodiversity through the extirpation of aquatic animals, but scientific evaluation of the effectiveness of pond draining is lacking. We conducted a large-scale field study to evaluate the effects of pond draining on invasive animal control, water quality, and aquatic biodiversity relative to different pond-management practices, pond physicochemistry, and surrounding land use. The results of boosted regression-tree models and analyses of similarity showed that pond draining had little effect on invasive fish control, water quality, or aquatic biodiversity. Draining even facilitated the colonization of farm ponds by invasive red swamp crayfish (Procambarus clarkii), which in turn may have detrimental effects on the biodiversity and water quality of farm ponds. Our results highlight the need for reconsidering current pond management and developing management plans with respect to multifunctionality of such ponds. Efectos del Drenado de Estanques sobre la Biodiversidad y la Calidad del Agua en Estanques de Cultivo. © 2013 Society for Conservation Biology.

Water chemistry and endangered white-clawed Crayfish: a literature review and field study of water chemistry association in Austropotamobius pallipes

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Haddaway N.R.

2015-01-01

Full Text Available Populations of the endangered white-clawed crayfish (Austropotamobius pallipes have rapidly declined in distribution and density in recent decades as a result of invasive crayfish, disease and habitat degradation. The species is thought to be particularly sensitive to water chemistry, and has been proposed as a bio-indicator of water quality. Here we detail the results of a systematic review of the literature regarding the chemistry of waterbodies inhabited by white-clawed crayfish, along with a wide-scale field study of the chemistry of crayfish-inhabited waterbodies in the UK. We use these data to examine potentially significant variables influencing crayfish distribution. Several variables appear to have thresholds that affect crayfish distribution; crayfish presence was associated with high dissolved oxygen, low conductivity, ammonium, sodium, and phosphate, and to a lesser extent low sulphate, nitrate, and total suspended solids. Some variables (magnesium, potassium, sodium, sulphate, nitrate, and total suspended solids may be tolerated at moderate to high concentrations in isolation (indicated by the presence of some populations in high levels of these variables, but suites of chemical conditions may act synergistically in situ and must be considered together. Recent efforts to conserve white-clawed crayfish have included relocations to Ark Sites; novel protected habitats with reduced risk of the introduction of disease, invasive crayfish and habitat degradation. We use our findings to propose the first detailed guidelines for common water chemistry variables of potential Ark Sites for the conservation of the species throughout its European range.

Crayfish impact desert river ecosystem function and litter-dwelling invertebrate communities through association with novel detrital resources.

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Eric K Moody

Full Text Available Shifts in plant species distributions due to global change are increasing the availability of novel resources in a variety of ecosystems worldwide. In semiarid riparian areas, hydric pioneer tree species are being replaced by drought-tolerant plant species as water availability decreases. Additionally, introduced omnivorous crayfish, which feed upon primary producers, allochthonous detritus, and benthic invertebrates, can impact communities at multiple levels through both direct and indirect effects mediated by drought-tolerant plants. We tested the impact of both virile crayfish (Orconectes virilis and litter type on benthic invertebrates and the effect of crayfish on detrital resources across a gradient of riparian vegetation drought-tolerance using field cages with leaf litter bags in the San Pedro River in Southeastern Arizona. Virile crayfish increased breakdown rate of novel drought-tolerant saltcedar (Tamarix ramosissima, but did not impact breakdown of drought-tolerant seepwillow (Baccharis salicifolia or hydric Fremont cottonwood (Populus fremontii and Gooding's willow (Salix goodingii. Effects on invertebrate diversity were observed at the litter bag scale, but no effects were found at the cage scale. Crayfish decreased alpha diversity of colonizing macroinvertebrates, but did not affect beta diversity. In contrast, the drought-tolerant litter treatment decreased beta diversity relative to hydric litter. As drought-tolerant species become more abundant in riparian zones, their litter will become a larger component of the organic matter budget of desert streams which may serve to homogenize the litter-dwelling community and support elevated populations of virile crayfish. Through impacts at multiple trophic levels, crayfish have a significant effect on desert stream ecosystems.

Integral handling of the swamps for indigenous communities - Caribbean of Colombia

International Nuclear Information System (INIS)

Sanchez Paez, Heliodoro; Ulloa Delgado Giovanni, Andres; Tavera Escobar, Hector Arsenio

2004-06-01

The book includes topics like the ecosystems of swamps, zonification for its handling, growth of species of swamps, restoration and vegetation, integral plan of handling of swamps and its fauna among other topics

Range extensions of three crayfishes (Faxonius yanahlindus, F. placidus, and F. erichsonianus) into Mississippi

Science.gov (United States)

Susan B. Adams; Robert L. Jones

2018-01-01

We report 3 new state crayfish records from the Tennessee River drainage in Tishomingo County, Mississippi: 1 is a re-identification of previously published material, and 2 are from unpublished collections. Faxonius yanahlindus (Spinywrist Crayfish), recently described from the middle Tennessee River drainage in northwest Alabama and southern...

Regeneration potential of Taxodium distichum swamps and climate change

Science.gov (United States)

Middleton, B.A.

2009-01-01

Seed bank densities respond to factors across local to landscape scales, and therefore, knowledge of these responses may be necessary in forecasting the effects of climate change on the regeneration of species. This study relates the seed bank densities of species of Taxodium distichum swamps to local water regime and regional climate factors at five latitudes across the Mississippi River Alluvial Valley from southern Illinois to Louisiana. In an outdoor nursery setting, the seed banks of twenty-five swamps were exposed to non-flooded (freely drained) or flooded treatments, and the number and species of seeds germinating were recorded from each swamp during one growing season. Based on ANOVA analysis, the majority of dominant species had a higher rate of germination in non-flooded versus flooded treatments. Similarly, an NMS comparison, which considered the local water regime and regional climate of the swamps, found that the species of seeds germinating, almost completely shifted under non-flooded versus flooded treatments. For example, in wetter northern swamps, seeds of Taxodium distichum germinated in non-flooded conditions, but did not germinate from the same seed banks in flooded conditions. In wetter southern swamps, seeds of Eleocharis cellulosa germinated in flooded conditions, but did not germinate in non-flooded conditions. The strong relationship of seed germination and density relationships with local water regime and regional climate variables suggests that the forecasting of climate change effects on swamps and other wetlands needs to consider a variety of interrelated variables to make adequate projections of the regeneration responses of species to climate change. Because regeneration is an important aspect of species maintenance and restoration, climate drying could influence the species distribution of these swamps in the future. ?? 2008 Springer Science+Business Media B.V.

The scientific value and potential of New Zealand swamp kauri

Science.gov (United States)

Lorrey, Andrew M.; Boswijk, Gretel; Hogg, Alan; Palmer, Jonathan G.; Turney, Christian S. M.; Fowler, Anthony M.; Ogden, John; Woolley, John-Mark

2018-03-01

New Zealand swamp kauri (Agathis australis) are relic trees that have been buried and preserved in anoxic bog environments of northern New Zealand for centuries through to hundreds of millennia. Kauri are massive in proportion to other native New Zealand trees and they can attain ages greater than 1000 years. The export market for swamp (subfossil) kauri has recently been driven by demand for a high-value workable timber, but there are concerns about the sustainability of the remaining resource, a situation exacerbated in recent years by the rapid extraction of wood. Economic exploitation of swamp kauri presents several unique opportunities for Quaternary science, however the scientific value of this wood is not well understood by the wider research community and public. Here, we summarise the history of scientific research on swamp kauri, and explore the considerable potential of this unique resource. Swamp kauri tree-ring chronologies are temporally unique, and secondary analyses (such as radiocarbon and isotopic analyses) have value for improving our understanding of Earth's recent geologic history and pre-instrumental climate history. Swamp kauri deposits that span the last interglacial-glacial cycle show potential to yield "ultra-long" multi-millennia tree-ring chronologies, and composite records spanning large parts of MIS3 (and most of the Holocene) may be possible. High-precision radiocarbon dating of swamp kauri chronologies can improve the resolution of the global radiocarbon calibration curve, while testing age modelling and chronologic alignment of other independent long-term high-resolution proxy records. Swamp kauri also has the potential to facilitate absolute dating and verification of cosmogenic events found in long Northern Hemisphere tree-ring chronologies. Future efforts to conserve these identified values requires scientists to work closely with swamp kauri industry operators, resource consent authorities, and export regulators to mitigate

Nutritional treatment of cancer cachexia in rats. Use of a diet formulated with a crayfish enzymatic extract.

Science.gov (United States)

Cremades, Olga; Parrado, Juan; Jover, María; Collantes de Terán, Laura; Gutiérrez, Juan Francisco; Bautista Palomas, Juan D

2007-09-01

Terminal cancer-associated cachexia, characterized by a marked weight loss, anorexia, asthenia and anemia, is usually associated with a malnutrition status. To investigate whether a diet formulated with a crayfish enzymatic extract, enriched in essential amino acids, omega-3 fatty acids, and astaxanthin, would be effective for the treatment of cancer-associated cachexias, by decreasing mortality and morbidity rates in cachectic rats and/or improving survival. Two types of diet were used: a standard diet and one formulated with crayfish enzymatic extract. Rats were divided into two groups (24 animals per group): one without tumor (T-) and the other with tumor (T+) (AH-130 Yoshida ascites hepatoma). Each group was further divided into two subgroups (12 animals per subgroup). Two subgroups (T-(standard) and T+(standard)) were fed the standard diet and the other two (T-(CFEE) and T+(CFEE)) the crayfish enzymatic extract one for four weeks, after which different tissue and plasma parameters were studied. The implantation of the tumor resulted in a considerable loss of muscle and adipose tissue mass in both groups, but the loss of muscle and fat was lower in the group fed the crayfish enzymatic extract diet. There was also a concomitant increase in the plasma concentration of TNF-alpha, although the increase was smaller in the crayfish enzymatic extract-treated group. This study shows that although the treatment of cachetic rats with the crayfish enzymatic extract diet did not revert the cachexia, it increased survival (57.1% vs. 25.9% in the group treated with crayfish enzymatic extract and standard diets, respectively) and meliorated the cachexia symptoms--anorexia and body mass loss (muscle and adipose tissue).

An invaded invader: high prevalence of entocytherid ostracods on the red swamp crayfish Procambarus clarkii (Girard, 1852) in the Eastern Iberian Peninsula

Czech Academy of Sciences Publication Activity Database

Aguilar-Alberola, J. A.; Mesquita-Joanes, F.; López, S.; Mestre, A.; Casanova, J. C.; Rueda, J.; Ribas, Alexis

2012-01-01

Roč. 688, č. 1 (2012), s. 63-73 ISSN 0018-8158 Institutional research plan: CEZ:AV0Z60930519 Keywords : Ostracoda * Commensalism * Alien species * Biological invasion Subject RIV: EG - Zoology Impact factor: 1.985, year: 2012

Bioaccumulation of lead nitrate in freshwater crayfish (Astacus leptodactylus) tissues under aquaculture conditions.

Science.gov (United States)

Naghshbandi, N; Zare, S; Heidari, R; Soleimani Palcheglu, S

2007-09-15

The aim of this research was to evaluate the amount of lead in the tissue of Astacus leptodactylus especially in their muscle which the consumed part of their body. In this study the crayfish was exposed to intermediate concentration of lead nitrate (500 microg L(-1)) for periods up to 3 weeks. In the first, second and third weeks bioaccumulation in various tissues was under investigation. The data of toxicological analysis obtained by the method of atomic absorption revealed that the levels of bioaccumulation of metal are different in various tissues of this crayfish. The accumulation of the lead in gills was the highest and in muscles was lowest degree. The amount of heavy metals in the tissues of crayfish was as follow. Gills>exoskeleton>hepatopancreas (digestive glands)>digestive tract>green gland>testis and ovary>muscles.

Predatory functional response and prey choice identify predation differences between native/invasive and parasitised/unparasitised crayfish.

Science.gov (United States)

Haddaway, Neal R; Wilcox, Ruth H; Heptonstall, Rachael E A; Griffiths, Hannah M; Mortimer, Robert J G; Christmas, Martin; Dunn, Alison M

2012-01-01

Invasive predators may change the structure of invaded communities through predation and competition with native species. In Europe, the invasive signal crayfish Pacifastacus leniusculus is excluding the native white clawed crayfish Austropotamobius pallipes. This study compared the predatory functional responses and prey choice of native and invasive crayfish and measured impacts of parasitism on the predatory strength of the native species. Invasive crayfish showed a higher (>10%) prey (Gammarus pulex) intake rate than (size matched) natives, reflecting a shorter (16%) prey handling time. The native crayfish also showed greater selection for crustacean prey over molluscs and bloodworm, whereas the invasive species was a more generalist predator. A. pallipes parasitised by the microsporidian parasite Thelohania contejeani showed a 30% reduction in prey intake. We suggest that this results from parasite-induced muscle damage, and this is supported by a reduced (38%) attack rate and increased (30%) prey handling time. Our results indicate that the per capita (i.e., functional response) difference between the species may contribute to success of the invader and extinction of the native species, as well as decreased biodiversity and biomass in invaded rivers. In addition, the reduced predatory strength of parasitized natives may impair their competitive abilities, facilitating exclusion by the invader.

Studies on mangrove swamps of Goa 1. Heterotrophic bacterial flora from mangrove swamps

Digital Repository Service at National Institute of Oceanography (India)

Matondkar, S.G.P; Mathani, S; Mavinkurve, S

Heterotrophic bacterial flora from the mangrove swamps of Goa consisted of physiologically active organisms exhibiting cellulolytic, pectinolytic, amylolytic, proteolytic and H2S forming activities, throughout the year. Coryneform and Bacillus were...

Comparative analysis of crayfish marketing in selected markets of ...

African Journals Online (AJOL)

Comparative analysis of crayfish marketing in selected markets of Akwa Ibom and Abia States, Nigeria. ... It specifically looked at market integration, costs and return, marketing margin, marketing ... EMAIL FULL TEXT EMAIL FULL TEXT

Differences in aggression, activity and boldness between native and introduced populations of an invasive crayfish

Science.gov (United States)

Pintor, L.M.; Sih, A.; Bauer, M.L.

2008-01-01

Aggressiveness, along with foraging voracity and boldness, are key behavioral mechanisms underlying the competitive displacement and invasion success of exotic species. However, do aggressiveness, voracity and boldness of the invader depend on the presence of an ecologically similar native competitor in the invaded community? We conducted four behavioral assays to compare aggression, foraging voracity, threat response and boldness to forage under predation risk of multiple populations of exotic signal crayfish Pacifastacus leniusculus across its native and invaded range with and without a native congener, the Shasta crayfish P. fortis. We predicted that signal crayfish from the invaded range and sympatric with a native congener (IRS) should be more aggressive to outcompete a close competitor than populations from the native range (NR) or invaded range and allopatric to a native congener (IRA). Furthermore, we predicted that IRS populations of signal crayfish should be more voracious, but less bold to forage under predation risk since native predators and prey likely possess appropriate behavioral responses to the invader. Contrary to our predictions, results indicated that IRA signal crayfish were more aggressive towards conspecifics and more voracious and active foragers, yet also bolder to forage under predation risk in comparison to NR and IRS populations, which did not differ in behavior. Higher aggression/voracity/ boldness was positively correlated with prey consumption rates, and hence potential impacts on prey. We suggest that the positive correlations between aggression/voracity/boldness are the result of an overall aggression syndrome. Results of stream surveys indicated that IRA streams have significantly lower prey biomass than in IRS streams, which may drive invading signal crayfish to be more aggressive/voracious/bold to acquire resources to establish a population. ?? 2008 The Authors.

Fish measurement using Android smart phone: the example of swamp eel

Science.gov (United States)

Chen, Baisong; Fu, Zhuo; Ouyang, Haiying; Sun, Yingze; Ge, Changshui; Hu, Jing

The body length and weight are critical physiological parameters for fishes, especially eel-like fishes like swamp eel(Monopterusalbus).Fast and accurate measuring of body length is significant for swamp eel culturing as well as its resource investigation and protection. This paper presents an Android smart phone-based photogrammetry technology for measuring and estimating the length and weight of swamp eel. This method utilizes the feature that the ratio of lengths of two objects within an image is equal to that of in reality to measure the length of swamp eels. And then, it estimates the weight via a pre-built length-weight regression model. Analysis and experimental results have indicated that this method is a fast and accurate method for length and weight measurements of swamp eel. The cross-validation results shows that the RMSE (root-mean-square error) of total length measurement of swamp eel is0.4 cm, and the RMSE of weight estimation is 11 grams.

ECOLOGICAL CHARACTERISATION OF STREAMS IN TUSCANY (ITALY FOR THE MANAGEMENT OF THE THREATENED CRAYFISH AUSTROPOTAMOBIUS PALLIPES COMPLEX

Directory of Open Access Journals (Sweden)

RENAI B.

2006-01-01

Full Text Available Any initiative aimed at the management of a threatened species needs a good knowledge of its environmental requirements. Aims of this study were to individuate suitable areas for the reintroduction of crayfish species belonging to the Austropotamobius pallipes complex and to evaluate the causes of the local extinction in Tuscany (Italy of some populations. Between May 2003 and September 2004, we collected ecological data from 19 streams of 4 catchments, 9 watercourses where crayfish were present (WI and 10 where they were present in the recent past and absent now (WO, and we compared them. Multivariate analyses were performed using chemico-physical and biotic parameters to examine the relationships between their values and the presence of crayfish. The results did not allow us to find significant differences between the two categories of streams, suggesting their suitability for crayfish reintroduction.

Comparative study of freshwater crayfish, Cherax spp. (crustaceae: decapoda: parastacidae) from Papua, Indonesia based on length-weight analysis

Science.gov (United States)

Hamidah, H.; Abinawanto, Bowolaksono, A.

2017-07-01

The freshwater crayfish is one of the most important fish species as the protein resources. Lake and rivers are the habitat of crayfish in Papua. Morphological characters of crayfish, such as color, total body lengths (L) and body weight (W) were influenced by the habitat. The purpose of the study, therefore, was to compare the total body length and body weight as well as the unique color of crayfish from Uter lake (Atinjo district), Seremuk river (Haha village), Baliem river (Pike village; Hubukiak district, Jayawijaya), and Baliem river (Wesaput village; Wesaput district). Length-weight (body length; LB versus wet weight; WWT) relationships were determined for male and female crayfish (Cherax spp.) The length-weight relationships of total individuals was W = 0,022215.L3,159. This regression differed significantly (R2 = 97.5 %) between locations. Both males and females exhibited positive allometric growth as statistical difference was observed in the mean of the wet weight and body length between males and females. Besides, Canonical function was subjected to determine population distribution based on length-weight data.

Histological changes and antioxidant enzyme activity in signal crayfish (Pacifastacus leniusculus) associated with sub-acute peracetic acid exposure.

Science.gov (United States)

Chupani, Latifeh; Zuskova, Eliska; Stara, Alzbeta; Velisek, Josef; Kouba, Antonin

2016-01-01

Peracetic acid (PAA) is a powerful disinfectant recently adopted as a therapeutic agent in aquaculture. A concentration of 10 mg L(-1) PAA effectively suppresses zoospores of Aphanomyces astaci, the agent of crayfish plague. To aid in establishing safe therapeutic guideline, the effects of PAA on treated crayfish were investigated through assessment of histological changes and oxidative damage. Adult female signal crayfish Pacifastacus leniusculus (n = 135) were exposed to 2 mg L(-1) and 10 mg L(-1) of PAA for 7 days followed by a 7 day recovery period in clean water. Superoxide dismutase activity was significantly lower in gill and hepatopancreas after three days exposure to 10 mg L(1) PAA than in the group treated with 2 mg L(-1) PAA and a control in only clean water. Catalase activity in gill and hepatopancreas remained unaffected by both exposures. Glutathione reductase was significantly decreased in gill of 10 mg L(-1) PAA treated crayfish and increased in group exposed to 2 mg L(-1) compared to control after 7 days exposure. Antioxidant enzyme activity in exposed groups returned to control values after recovery period. Gill, hepatopancreas, and antennal gland showed slight damage in crayfish treated with 2 mg L(-1) of PAA compared to the control group. The extent and frequency of histological alterations were more pronounced in animals exposed to 10 mg L(-1). The gill was the most affected organ, infiltrated by granular hemocytes and displaying malformations of lamella tips and disorganization of epithelial cells. After a 7 day recovery period, the infiltrating cells in affected tissues of the exposed crayfish began to return to normal levels. Results suggested that the given concentrations could be applied to signal crayfish against crayfish plague agent in aquaculture; however, further studies are required for safe use. Copyright © 2015 Elsevier Ltd. All rights reserved.

ANNUAL ACTIVITY OF THE NOBLE CRAYFISH (ASTACUS ASTACUS IN THE ORLJAVA RIVER (CROATIA

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FALLER M.

2006-07-01

Full Text Available We studied the annual activity of the noble crayfish (Astacus astacus at three sites along the Orljava River, in the continental part of Croatia, between August 2003 and September 2004. Each site represented the typical characteristics of the upper, middle and lower section of the river (5, 24 and 37 km from the spring, respectively. The biggest population size was recorded on the most upstream site, with greatest structural variability of bottom, high biotic index, and the lowest mean water temperature. Males dominated in catch during the whole research period (total sex ratio was 1.77 males: 1 female. The number of caught crayfish fluctuated during the year and their activity was positively correlated with the water temperature. The crayfish catch within the two downstream sites was dramatically lower in the autumn 2004 then the year before. No obvious reason could be found; therefore we concluded that this was probably result of natural fluctuations in population. Males were significantly longer than females on all three sites. Males and females had similar percentages of injuries, mainly on claws and antennae. Crayfish were active during the whole year, even when water temperature was just 1°C. Phases of life cycle (moulting, active cement glands, mating, hatchlings occurred a month later in our population than in the Northern Europe populations, probably as a consequence of differences in the climate.

Response of tropical peat swamp forest tree species seedlings to macro nutrients

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Tri Wira Yuwati

2015-10-01

Full Text Available Abstract Efforts of restoration of degraded tropical peat swamp forest were facing constraints due to the low available nutrient level of peat. The transplanted peat swamp forest species seedlings experienced low survival rate and poor growth performance. This study aimed to demonstrate the response of ten tropical peat swamp forest species seedlings whether climax and pioneer species to macro-nutrients addition in the nursery. The growth performance of climax and pioneer tropical peat swamp species seedlings was recorded following addition of macro nutrients of Nitrogen (N, Phosphorus(P, Potassium(K and Dolomitic limestone (CaMg. The result showed that Alstonia spatulata and Parartocarpus venenosus showed positive growth response following macro nutrients addition. This study concluded that tropical peat swamp pioneer species has lower necessity for macro-nutrients addition than tropical peat swamp climax species.

Histological analysis of thelohaniasis in white-clawed crayfish Austropotamobius pallipes complex

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Quaglio F.

2011-09-01

Full Text Available From 2004 to 2006, a parasitological survey aimed at the detection of the microsporidian parasite Thelohania contejeani Henneguy was carried out on 177 wild white-clawed crayfish (Austropotamobius pallipes complex captured in six streams and rivers of the province of Belluno in north-eastern Italy. Microscopical examination of the skeletal muscles, and histological analysis applying different histochemical stains to full transverse and sagittal sections of the cephalothorax and abdomen were carried out. Transmission electron microscopy (TEM was also conducted on the parasites recovered during the survey. Out of 177 crayfish examined, Thelohania contejeani (Microsporidia, Thelohaniidae was present in only one crayfish from the Vena d’oro creek. The parasite was detected in the skeletal muscles in several developmental stages, including mature spores, which represented the most common stage recovered. Sporophorous vesicles were also present. Histological examination revealed that the fibres of the skeletal, cardiac and intestinal muscles were filled with spores. Melanin infiltrations were focally present in the infected striated muscles. The gill phagocytic nephrocytes were engulfed by small masses of spores. Among the staining techniques applied, Crossman’s trichrome stain represented the most effective method of detecting T. contejeani.

A global review of freshwater crayfish temperature tolerance, preference, and optimal growth

Science.gov (United States)

Westhoff, Jacob T.; Rosenberger, Amanda E.

2016-01-01

Conservation efforts, environmental planning, and management must account for ongoing ecosystem alteration due to a changing climate, introduced species, and shifting land use. This type of management can be facilitated by an understanding of the thermal ecology of aquatic organisms. However, information on thermal ecology for entire taxonomic groups is rarely compiled or summarized, and reviews of the science can facilitate its advancement. Crayfish are one of the most globally threatened taxa, and ongoing declines and extirpation could have serious consequences on aquatic ecosystem function due to their significant biomass and ecosystem roles. Our goal was to review the literature on thermal ecology for freshwater crayfish worldwide, with emphasis on studies that estimated temperature tolerance, temperature preference, or optimal growth. We also explored relationships between temperature metrics and species distributions. We located 56 studies containing information for at least one of those three metrics, which covered approximately 6 % of extant crayfish species worldwide. Information on one or more metrics existed for all 3 genera of Astacidae, 4 of the 12 genera of Cambaridae, and 3 of the 15 genera of Parastacidae. Investigations employed numerous methodological approaches for estimating these parameters, which restricts comparisons among and within species. The only statistically significant relationship we observed between a temperature metric and species range was a negative linear relationship between absolute latitude and optimal growth temperature. We recommend expansion of studies examining the thermal ecology of freshwater crayfish and identify and discuss methodological approaches that can improve standardization and comparability among studies.

The first record of translocated white-clawed crayfish from the Austropotamobius pallipes complex in Sardinia (Italy

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Julien Amouret

2015-03-01

Full Text Available The white-clawed crayfish Austropotamobius pallipes complex is native to Europe, being present in 18 European countries, Italy included. However, the number and abundance of its populations are today restricted and it has been recently classified as “endangered” by IUCN (International Union for Conservation of Nature. Here, we report the first record of this freshwater crayfish in Sardinia Island (Italy. Using a fragment of the mitochondrial DNA 16S rRNA gene, we identified three haplotypes that correspond to the A. italicus meridionalis subclade. We provide information about the sampling area, population density and finally discuss hypotheses about the occurrence of this population in Sardinia, comparing it with other Mediterranean populations. Our results improve the existing knowledge about the phylogeography of the taxon across Italy, confirming its complex pattern of distribution. In addition to the non-native status of the Sardinian A. i. meridionalis crayfish, we showed that the most proximal Mediterranean population of white-clawed crayfish existing in Corsica belongs to A. pallipes from Southern France.

Predictions of marbled crayfish establishment in conurbations fulfilled: Evidences form the Czech republic

Czech Academy of Sciences Publication Activity Database

Patoka, J.; Buřič, M.; Kolář, Vojtěch; Bláha, M.; Petrtýl, M.; Franta, P.; Tropek, Robert; Kalous, L.; Petrusek, A.; Kouba, A.

2016-01-01

Roč. 71, č. 12 (2016), s. 1380-1385 ISSN 0006-3088 R&D Projects: GA ČR GAP504/12/2525 Grant - others:GA JU(CZ) 158/2016/P; GA MŠk(CZ) LO1205 Institutional support: RVO:60077344 Keywords : Procambarus fallax f. virginalis * biological invasion * first record Subject RIV: EH - Ecology, Behaviour Impact factor: 0.759, year: 2016

Hydrological disturbance diminishes predator control in wetlands.

Science.gov (United States)

Dorn, Nathan J; Cook, Mark I

2015-11-01

Effects of predators on prey populations can be especially strong in aquatic ecosystems, but disturbances may mediate the strength of predator limitation and even allow outbreaks of some prey populations. In a two-year study we investigated the numerical responses of crayfish (Procambarus fallax) and small fishes (Poeciliidae and Fundulidae) to a brief hydrological disturbance in replicated freshwater wetlands with an experimental drying and large predatory fish reduction. The experiment and an in situ predation assay tested the component of the consumer stress model positing that disturbances release prey from predator limitation. In the disturbed wetlands, abundances of large predatory fish were seasonally reduced, similar to dynamics in the Everglades (southern Florida). Densities of small fish were unaffected by the disturbance, but crayfish densities, which were similar across all wetlands before drying, increased almost threefold in the year after the disturbance. Upon re-flooding, juvenile crayfish survival was inversely related to the abundance of large fish across wetlands, but we found no evidence for enhanced algal food quality. At a larger landscape scale (500 km2 of the Everglades), crayfish densities over eight years were positively correlated with the severity of local dry disturbances (up to 99 days dry) during the preceding dry season. In contrast, densities of small-bodied fishes in the same wetlands were seasonally depressed by dry disturbances. The results from our experimental wetland drought and the observations of crayfish densities in the Everglades represent a large-scale example of prey population release following a hydrological disturbance in a freshwater ecosystem. The conditions producing crayfish pulses in the Everglades appear consistent with the mechanics of the consumer stress model, and we suggest crayfish pulses may influence the number of nesting wading birds in the Everglades.

Estudios biológicos sobre procambarus clarkii girard (decapoda cambaridae) en las marismas del bajo Guadalquivir

OpenAIRE

Cano Sánchez, Esperanza

1994-01-01

Procambarus clarkii Girard, es un cangrejo de agua dulce, vulgarmente conocido como cangrejo americano o rojo, originario de Estados Unidos (zona Sur central) y México (zona Noreste) (HOBBS, 1972 a). Fue introducido en Las Marismas del Bajo Guadalquivir en 1974 y debido a que presenta una alta tasa de reproducción, actividad excavadora y buena adaptación a zonas con drásticas fluctuaciones temporales en el nivel del agua (HUNER & BARR, 1984 a), en poco tiempo se extendió por toda la marisma. ...

Biology and control of swamp dodder (Cuscuta gronovii)

International Nuclear Information System (INIS)

Bewick, T.A.

1987-01-01

A simple model predicting swamp dodder (Cuscuta gronovii Willd.) emergence was developed. The model states that 0.1% of the cranberry seedlings will emerge after 150 to 170 GDD have accumulated after the winter ice has melted on the cranberry beds, using 0 C as the low temperature threshold. Experiments in cranberry showed that pronamide [3,5-dichloro-(N-1,1-dimethyl-2-propynyl)benzamide] was effective in controlling swamp dodder when applied preemergence. Rates below 2.4 kg ai/ha appeared to be safe for cranberry plants and fruit. Experiments with 14 C glyphosate showed that the herbicide moved out of carrot leaves to the physiological sinks in the plant. In carrots parasitized by swamp dodder the dodder acted as one of the strongest sinks for photosynthates from the host. In cranberry glyphosate moved out of the leaves, but most remained in the stem to which the treated leaves were attached. The only physiological sinks that accumulated significant amounts of label were the stem apices. The concentration of the herbicide in this sink decreased with time. Swamp dodder stems were able to absorb glyphosate directly from solution

Analysis of Technical Efficiency among Swamp Rice Farmers in ...

African Journals Online (AJOL)

This study was conducted to evaluate the Technical efficiency among swamp rice farmers in Niger State, Nigeria. A multi-stage sampling technique was used to select 159 swamp rice farmers. The data collected were analysed using descriptive statistics, and the stochastic frontier production function. The results showed ...

Natural crayfish clone as emerging model for various biological ...

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences; Volume 36; Issue 2. Marmorkrebs: Natural crayfish clone as emerging model for various biological disciplines. Günter Vogt. Mini-review Volume 36 Issue 2 June 2011 pp 377-382. Fulltext. Click here to view fulltext PDF. Permanent link:

Results of the 2000 Creek Plantation Swamp Survey

International Nuclear Information System (INIS)

Fledderman, P.D.

2000-01-01

This report is a survey of the Creek Plantation located along the Savannah River and borders the southeast portion of the Savannah River Site. The land is primarily undeveloped and agricultural; its purpose is to engage in equestrian-related operations. A portion of Creek Plantation along the Savannah River is a low-lying swamp, known as the Savannah River Swamp, which is uninhabited and not easily accessible

Swamp Buffalo in South Kalimantan : Problem, Disease and Control

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Lily Natalia

2006-12-01

Full Text Available In recent years, several studies have been carried out to evaluate and investigate the important diseases of swamp buffaloes (Bubalus carabanensis in Kalimantan . More attention has been focused on the case of acute infectious diseases and sudden death in the buffaloes . Fasciolosis black disease, acute enteritis, especially fatal enterotoxaemia haemorrhagic septicaemia . and trypanosomiasis (Surra, are some of the important diseases found in these animals . Black disease caused by toxigenic Clostridium novyi occurs in the presence of the organism in the liver and the degree of liver fluke Fasciola gigantica infestation . In regions where black disease is enzootic, Cl. novvi can be isolated from livers of normal healthy animals . In Hulu Sungai Utara district, South Kalimantan, the prevalence of fasciolosis caused by Fasciola gigantica in swamp buffalo was 77% in 1991 . A gross sudden change in diet due to seasonal changes could induce rumen and intestinal stasis, which provide a favourable environment for the rapid proliferation of commensal toxigenic Clostridium perfringens in the small intestine . Subsequent absorption of the toxin produced through the gut wall and its generalized dissemination culminated in a fatal enterotoxaemia . Haemorrhagic septicaemia (HS is an acute, fatal disease affecting swamp buffalo, and caused by Pasteurella multocida B : 2 . The swamp buffalo is particularly susceptible for HS, and the reported greatest losses of swamp buffalo in Kalimantan due to HS is recorded in 1980s. The clinical signs of Surra in swamp buffalo were also found in certain areas in Danau Panggang area . Hulu Sungai Utara district . Vaccination is the accepted method for controlling Black disease, enterotoxaemia and HS. Multi component vaccine, alum adjuvant containing at least 5 types of clostridial toxoids and P. multocida B2 bacterin have been used and provide good protection to the animals . Control and treatment of liver fluke infestation

Swamp Rice Production in Ogun Waterside Local Government Area ...

African Journals Online (AJOL)

This study examined the economics of swamp rice production among peasant farmers in the Waterside Local Government Area of Ogun State for 2001 cropping year. A total of 50 swamp rice farmers were randomly selected from 5 villages using multistage sampling technique. The data collected, with the aid of ...

Who is the boss? Individual recognition memory and social hierarchy formation in crayfish.

Science.gov (United States)

Jiménez-Morales, Nayeli; Mendoza-Ángeles, Karina; Porras-Villalobos, Mercedes; Ibarra-Coronado, Elizabeth; Roldán-Roldán, Gabriel; Hernández-Falcón, Jesús

2018-01-01

Under laboratory conditions, crayfish establish hierarchical orders through agonistic encounters whose outcome defines the dominant one and one, or more, submissive animals. These agonistic encounters are ritualistic, based on threats, pushes, attacks, grabs, and avoidance behaviors that include retreats and escape responses. Agonistic behavior in a triad of unfamiliar, size-matched animals is intense on the first day of social interaction and the intensity fades on daily repetitions. The dominant animal keeps its status for long periods, and the submissive ones seem to remember 'who the boss is'. It has been assumed that animals remember and recognize their hierarchical status by urine signals, but the putative substance mediating this recognition has not been reported. The aim of this work was to characterize this hierarchical recognition memory. Triads of unfamiliar crayfish (male animals, size and weight-matched) were faced during standardized agonistic protocols for five consecutive days to analyze memory acquisition dynamics (Experiment 1). In Experiment 2, dominant crayfish were shifted among triads to disclose whether hierarchy depended upon individual recognition memory or recognition of status. The maintenance of the hierarchical structure without behavioral reinforcement was assessed by immobilizing the dominant animal during eleven daily agonistic encounters, and considering any shift in the dominance order (Experiment 3). Standard amnesic treatments (anisomycin, scopolamine or cold-anesthesia) were given to all members of the triads immediately after the first interaction session to prevent individual recognition memory consolidation and evaluate its effect on the hierarchical order (Experiment 4). Acquisition of hierarchical recognition occurs at the first agonistic encounter and agonistic behavior gradually diminishes in the following days; animals keep their hierarchical order despite the inability of the dominant crayfish to attack the submissive

It takes time to see the menu from the body: an experiment on stable isotope composition in freshwater crayfishes

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Jussila J.

2015-01-01

Full Text Available For many applications and ecological studies in which wild individuals are brought to laboratory it would be essential to know accurately how fast novel diet is reflected in composition of different tissues. To study the effects of two different diets on the stable isotope composition of freshwater crayfish muscle and hemolymph, we conducted a three month experiment on noble crayfish (Astacus astacus and signal crayfish (Pacifastacus leniusculus by feeding them sweet corn (Zea mays or Baltic herring (Clupea harengus membras as novel food. During the experiment, the crayfish were given 0.4 g of selected food daily and the amount consumed was recorded. The samples for the stable isotope analyses were taken at the commencement of the experiment (initial control and three times (hemolymph or twice (muscle tissue during the experiment. We found that stable isotope changes can be similarly, and rather slowly, detected from muscle tissue and hemolymph under studied conditions. Hemolymph sampling, being non-lethal, can be recommended as a practical sampling method. Our results confirm earlier reports according to which diet changes reflect to crayfish isotope ratios slowly implying that isotope ratios indicate long-term diet.

The Sensitivity of the Crayfish Reward System to Mammalian Drugs of Abuse.

Science.gov (United States)

Shipley, Adam T; Imeh-Nathaniel, Adebobola; Orfanakos, Vasiliki B; Wormack, Leah N; Huber, Robert; Nathaniel, Thomas I

2017-01-01

The idea that addiction occurs when the brain is not able to differentiate whether specific reward circuits were triggered by adaptive natural rewards or falsely activated by addictive drugs exist in several models of drug addiction. The suitability of crayfish ( Orconectes rusticus ) for drug addiction research arises from developmental variation of growth, life span, reproduction, behavior and some quantitative traits, especially among isogenic mates reared in the same environment. This broad spectrum of traits makes it easier to analyze the effect of mammalian drugs of abuse in shaping behavioral phenotype. Moreover, the broad behavioral repertoire allows the investigation of self-reinforcing circuitries involving appetitive and exploratory motor behavior, while the step-wise alteration of the phenotype by metamorphosis allows accurate longitudinal analysis of different behavioral states. This paper reviews a series of recent experimental findings that evidence the suitability of crayfish as an invertebrate model system for the study of drug addiction. Results from these studies reveal that unconditioned exposure to mammalian drugs of abuse produces a variety of stereotyped behaviors. Moreover, if presented in the context of novelty, drugs directly stimulate exploration and appetitive motor patterns along with molecular processes for drug conditioned reward. Findings from these studies indicate the existence of drug sensitive circuitry in crayfish that facilitates exploratory behavior and appetitive motor patterns via increased incentive salience of environmental stimuli or by increasing exploratory motor patterns. This work demonstrates the potential of crayfish as a model system for research into the neural mechanisms of addiction, by contributing an evolutionary, comparative context to our understanding of natural reward as an important life-sustaining process.

The Sensitivity of the Crayfish Reward System to Mammalian Drugs of Abuse

Directory of Open Access Journals (Sweden)

Adam T. Shipley

2017-12-01

Full Text Available The idea that addiction occurs when the brain is not able to differentiate whether specific reward circuits were triggered by adaptive natural rewards or falsely activated by addictive drugs exist in several models of drug addiction. The suitability of crayfish (Orconectes rusticus for drug addiction research arises from developmental variation of growth, life span, reproduction, behavior and some quantitative traits, especially among isogenic mates reared in the same environment. This broad spectrum of traits makes it easier to analyze the effect of mammalian drugs of abuse in shaping behavioral phenotype. Moreover, the broad behavioral repertoire allows the investigation of self-reinforcing circuitries involving appetitive and exploratory motor behavior, while the step-wise alteration of the phenotype by metamorphosis allows accurate longitudinal analysis of different behavioral states. This paper reviews a series of recent experimental findings that evidence the suitability of crayfish as an invertebrate model system for the study of drug addiction. Results from these studies reveal that unconditioned exposure to mammalian drugs of abuse produces a variety of stereotyped behaviors. Moreover, if presented in the context of novelty, drugs directly stimulate exploration and appetitive motor patterns along with molecular processes for drug conditioned reward. Findings from these studies indicate the existence of drug sensitive circuitry in crayfish that facilitates exploratory behavior and appetitive motor patterns via increased incentive salience of environmental stimuli or by increasing exploratory motor patterns. This work demonstrates the potential of crayfish as a model system for research into the neural mechanisms of addiction, by contributing an evolutionary, comparative context to our understanding of natural reward as an important life-sustaining process.

Economic analysis of swamp rice production in Ebonyi Southern ...

African Journals Online (AJOL)

The aim of the paper is to analyze the determinants and profitability of the output of swamp rice farmers in Ebonyi southern Agricultural zone of Ebonyi State. Primary data were obtained through the use of structured questionnaires. A total of eighty (80) swamp rice farmers were randomly selected from the different blocks ...

Short Note Invasive Australian crayfish Cherax quadricarinatus in ...

African Journals Online (AJOL)

Most crayfish were between 50 and 59.9 mm carapace length. Males (average 82.6 g) were significantly heavier than females (37.2 g) and males were larger in carapace length, carapace width, chela length and chela width. A feral population of C. quadricarinatus is now established in the Sanyati Basin. Possible modes of ...

ROUNDTABLE SESSION 3: PHYLOGENY OF EUROPEAN CRAYFISH – IMPROVING THE TAXONOMY OF EUROPEAN CRAYFISH FOR A BETTER CONSERVATION

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SCHULZ H. K.

2005-07-01

Full Text Available This paper summarizes the various themes discussed in a roundtable session on the uses and usefulness of genetics for conservation of our European crayfish heritage. After reviewing the importance of characterizing the different genetic stocks (ESU: Evolutionary Significant Units of a species, where morphological criteria used for taxonomy, are utilizable with caution, the present state of knowledge of the phylogeny of European species was determined, in particular for the genus Austropotamobius which occupies most studies. There was a lively debate on the elevation to species rank of A. italicus. The status of knowledge of the taxonomy of Astacus astacus has been presented. Finally, given a major increase in works describing the genetic variability of natural populations of European crayfish, it was evident that an up to date inventory of the different research teams in this field should be developed, for several reasons – (i to describe these teams and their managers (thus facilitating contact (ii to list the species studied and the markers used (iii to give some recommendations on standardizing the use of certain markers or genes so as to allow comparison between the results collected by the various teams, and to apply them on a broader geographic scale.

Crayfish: a newly recognized vehicle for vibrio infections.

Science.gov (United States)

Bean, N H; Maloney, E K; Potter, M E; Korazemo, P; Ray, B; Taylor, J P; Seigler, S; Snowden, J

1998-10-01

We conducted a 1-year case-control study of sporadic vibrio infections to identify risk factors related to consumption of seafood products in two coastal areas of Louisiana and Texas. Twenty-six persons with sporadic vibrio infections and 77 matched controls were enrolled. Multivariate analysis revealed that crayfish (P Vibrio parahemolyticus infection (OR 9.24, P vibrio infection.

CRAYFISH AND ITS CULTURE IN UKRAINE. THEMATIC REFERENCES LIST

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I. Hrytsyniak

2014-09-01

Full Text Available Purpose. To compile a thematic references list on the problems of biology, physiology, pathology and crayfish breeding in Ukraine. Methodology. As the search base for the realization of the purpose was the scientific library stock of the Institute of Fisheries NAAS. The methods that have been preferred were both integrated and selective. Findings. We prepared a thematic reference list of the main scientific works, such as collections of scientific papers, proceedings of international scientific conferences, articles and candidate’s thesis abstracts on the biology of crustaceans and their cultivation in Ukraine, including the literature sources since 1958. The bibliography contains 37 publications of the Institute of Fisheries NAAS scientific library stock, in alphabetical order, and described according to DSTU GOST 7.1:2006 «System of standards on information, librarianship and publishing. Bibliographic entry. Bibliographic description. General requirements and rules». Practical value. The list may be helpful for experts, scientists, students, who are interested in problems of crayfish biology and culture.

Drug-sensitive reward in crayfish: an invertebrate model system for the study of SEEKING, reward, addiction, and withdrawal.

Science.gov (United States)

Huber, Robert; Panksepp, Jules B; Nathaniel, Thomas; Alcaro, Antonio; Panksepp, Jaak

2011-10-01

In mammals, rewarding properties of drugs depend on their capacity to activate appetitive motivational states. With the underlying mechanisms strongly conserved in evolution, invertebrates have recently emerged as a powerful new model in addiction research. In crayfish natural reward has proven surprisingly sensitive to human drugs of abuse, opening an unlikely avenue of research into the basic biological mechanisms of drug addiction. In a series of studies we first examined the presence of natural reward systems in crayfish, then characterized its sensitivity to a wide range of human drugs of abuse. A conditioned place preference (CPP) paradigm was used to demonstrate that crayfish seek out those environments that had previously been paired with the psychostimulants cocaine and amphetamine, and the opioid morphine. The administration of amphetamine exerted its effects at a number of sites, including the stimulation of circuits for active exploratory behaviors (i.e., SEEKING). A further study examined morphine-induced reward, extinction and reinstatement in crayfish. Repeated intra-circulatory infusions of morphine served as a reward when paired with distinct visual or tactile cues. Morphine-induced CPP was extinguished after repeated saline injections. Following this extinction phase, morphine-experienced crayfish were once again challenged with the drug. The priming injections of morphine reinstated CPP at all tested doses, suggesting that morphine-induced CPP is unrelenting. In an exploration of drug-associated behavioral sensitization in crayfish we concurrently mapped measures of locomotion and rewarding properties of morphine. Single and repeated intra-circulatory infusions of morphine resulted in persistent locomotory sensitization, even 5 days following the infusion. Moreover, a single dose of morphine was sufficient to induce long-term behavioral sensitization. CPP for morphine and context-dependent cues could not be disrupted over a drug free period of 5

Palynology, sedimentology and environmental significance of Holocene swamps at northern Kaitoke, Great Barrier Island, New Zealand

International Nuclear Information System (INIS)

Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

2000-01-01

Pollen and sediment analyses of two cores from coastal freshwater swamps at northern Kaitoke (Kaitoke Swamp and Police Station Swamp), Great Barrier Island, show that c. 7300 calibrated yr BP Kaitoke Swamp was an estuary with tidal flats. Avicennia, now absent from the swamp area, was present in the estuary. By c. 4500 yr BP fresh water conditions had developed at the Kaitoke Swamp site as marine influences decreased. Around the same time, fresh water swamp conditions commenced at the Police Station Swamp site on the surface of a low lying area of a Late Pleistocene dune. A sandy layer at Kaitoke may represent rapid infilling followed by a dry soil surface until c. 1000 yr BP. Conifer-hardwood forest on the hills surrounding the sites c. 7300-c. 1800 yr BP was dominated by Dacrydium and Metrosideros. During this period, environmental conditions were relatively stable, with little change in forest composition. Between 1800 yr and 800 yr BP Kaitoke Swamp was reflooded, and the Police Station Swamp extended as a shallow lake over the nearby dune flat. These new shallow swamps were invaded by swamp forest (mainly Dacrycaprus with some Laurelia). The presence of charcoal and Pteridium spores above the Kaharoa Tephra suggests that major Polynesian deforestation at northern Kaitoke began c. 600 calibrated yr BP. (author). 41 refs., 4 figs., 2 tabs

The potential for using red claw crayfish and hybrid African catfish as biological control agents for Schistosoma host snails

NARCIS (Netherlands)

Monde, C.; Syampungani, S.; Rico, A.; Brink, van den P.J.

2017-01-01

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After

Benefits of Riverine Water Discharge into the Lorian Swamp, Kenya

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Zipporah Musyimi

2012-12-01

Full Text Available Use and retention of river water in African highlands deprive communities in arid lowlands of their benefits. This paper reviews information on water use in the Ewaso Ng’iro catchment, Kenya, to evaluate the effects of upstream abstraction on the Lorian Swamp, a wetland used by pastoralists downstream. We first assess the abstractions and demands for water upstream and the river water supplies at the upper and the lower end of the Lorian Swamp. Further analysis of 12 years of monthly SPOT-VEGETATION satellite imagery reveals higher NDVI (Normalized Differential Vegetation Index values in the swamp than nearby rainfed areas, with the difference in NDVI between the two positively related to river water discharged into the swamp. The paper next reviews the benefits derived from water entering the swamp and the vulnerability to abstractions for three categories of water: (i the surface water used for drinking and sanitation; (ii the surface water that supports forage production; and (iii the water that recharges the Merti Aquifer. Our results suggest that benefits from surface water for domestic use and forage production are vulnerable to abstractions upstream whereas the benefits from the aquifer, with significant fossil water, are likely to be affected in the long run, but not the short term.

Isolation of heat-tolerant myoglobin from Asian swamp eel Monopterus albus.

Science.gov (United States)

Chotichayapong, Chatrachatchaya; Wiengsamut, Kittipong; Chanthai, Saksit; Sattayasai, Nison; Tamiya, Toru; Kanzawa, Nobuyuki; Tsuchiya, Takahide

2012-10-01

Myoglobin from Asian swamp eel Monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. The purified Mb of 0.68 mg/g wet weight of muscle was determined for its molecular mass by MALDI-TOF-MS to be 15,525.18 Da. Using isoelectric focusing technique, the purified Mb showed two derivatives with pI of 6.40 and 7.12. Six peptide fragments of this protein identified by LC-MS/MS were homologous to Mbs of sea raven Hemitripterus americanus, yellowfin tuna Thunnus albacores, blue marlin Makaira nigicans, common carp Cyprinus carpio, and goldfish Carassius auratus. According to the Mb denaturation, the swamp eel Mb had thermal stability higher than walking catfish Clarias batrachus Mb and striped catfish Pangasius hypophthalmus Mb, between 30 and 60 (°)C. For the thermal stability of Mb, the swamp eel Mb showed a biphasic behavior due to the O(2) dissociation and the heme orientation disorder, with the lowest increase in both Kd(f) and Kd(s). The thermal sensitivity of swamp eel Mb was lower than those of the other Mbs for both of fast and slow reaction stages. These results suggest that the swamp eel Mb globin structure is thermally stable, which is consistent with heat-tolerant behavior of the swamp eel particularly in drought habitat.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States.

Science.gov (United States)

Cooksey-Stowers, Kristen; Schwartz, Marlene B; Brownell, Kelly D

2017-11-14

This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data from the United States Department of Agriculture (USDA) Food Environment Atlas, the American Community Survey, and a commercial street reference dataset. We employed an instrumental variables (IV) strategy to correct for the endogeneity of food environments (i.e., that individuals self-select into neighborhoods and may consider food availability in their decision). Our results suggest that the presence of a food swamp is a stronger predictor of obesity rates than the absence of full-service grocery stores. We found, even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All three food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on rates of adult obesity ( p values ranged from 0.00 to 0.16). Our adjustment for reverse causality, using an IV approach, revealed a stronger effect of food swamps than would have been obtained by naïve ordinary least squares (OLS) estimates. The food swamp effect was stronger in counties with greater income inequality ( p food outlets and incentivizing healthy food retailers to locate in underserved neighborhoods warrant consideration as strategies to increase health equity.

Biophysics environmental conditions of swamp buffalo Bubalus bubalis Pampangan in district Rambutan South Sumatera

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Yuanita Windusari

2015-06-01

Full Text Available Swamp buffalo (Bubalus bubalis is a germ plasm specific of Pampangan and endemic in South Sumatera with low productivity and limited distribution. The aims of this study was to obtain information regarding biophysical conditions in the central areas of swamp buffalo in South Sumatera. The method used is purposive sampling method. Data collected in the form of quantitative and qualitative. Primary data were obtained through direct observation, interviews breeders selected as respondents while secondary data obtained from various related. The data obtained are presented descriptively and data tabulation. Productivity of swamp buffalo Pampangan can be increased by managing and maintaining habitat conditions although traditional maintenance. The results of observations of the biophysical condition of swamp buffalo (B. bubalis Pampangan showed that habitat of swamp buffalo Pampangan consists of dominated by lowland swamp area is overgrown with shrubs and grass. The conclution of the research are productivity and population of swamp buffalo (B. bubalis pampangan as specific plasma nutfah of South Sumatra can be improved by studying the characteristics and preferred habitat of the buffalo, although developed in a traditional farms but is good enough and so need to be developed, grass is most preferred by swamp buffalo Pampangan derived from ‘Kumpai’ grass group, and ‘Kasur’grass and ‘Kumpai’ grass is the dominant grass type found in habitat swamp buffalo Pampangan.

COMPARISON AMONG PRE-GELATINIZED STARCHES OF DIFFERENT BOTANICAL ORIGINS USED IN NOBLE CRAYFISH ASTACUS ASTACUS DIETS

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D’AGARO E.

2006-01-01

Full Text Available The objective of the present experiment was to compare the biological value and the binding functionality of four pre-gelatinized starches (wheat, diet 1; waxy maize, diet 2; maize, diet 3 and potato, diet 4 used in crayfish diets. 360 juvenile of A. astacus (initial b.w.: 0.70 ± 0.15 g were cultured in 12 tanks for 43d. Growth performance were significantly higher in crayfish fed diets containing wheat and waxy maize compared to those containing maize and potato pre-gelatinized starches. Disintegration in water and shear force tests of diets confirmed the superior binding capability of pre-gelatinized starches obtained from wheat and waxy maize. These results suggest that the pregelatinized wheat and waxy maize starches are the best choice for the production of diets for the noble crayfish.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States

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Kristen Cooksey-Stowers

2017-11-01

Full Text Available This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data from the United States Department of Agriculture (USDA Food Environment Atlas, the American Community Survey, and a commercial street reference dataset. We employed an instrumental variables (IV strategy to correct for the endogeneity of food environments (i.e., that individuals self-select into neighborhoods and may consider food availability in their decision. Our results suggest that the presence of a food swamp is a stronger predictor of obesity rates than the absence of full-service grocery stores. We found, even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All three food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on rates of adult obesity (p values ranged from 0.00 to 0.16. Our adjustment for reverse causality, using an IV approach, revealed a stronger effect of food swamps than would have been obtained by naïve ordinary least squares (OLS estimates. The food swamp effect was stronger in counties with greater income inequality (p < 0.05 and where residents are less mobile (p < 0.01. Based on these findings, local government policies such as zoning laws simultaneously restricting access to unhealthy food outlets and incentivizing healthy food retailers to locate in underserved neighborhoods warrant consideration as strategies to increase health equity.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States

Science.gov (United States)

Cooksey-Stowers, Kristen; Schwartz, Marlene B.; Brownell, Kelly D.

2017-01-01

This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data from the United States Department of Agriculture (USDA) Food Environment Atlas, the American Community Survey, and a commercial street reference dataset. We employed an instrumental variables (IV) strategy to correct for the endogeneity of food environments (i.e., that individuals self-select into neighborhoods and may consider food availability in their decision). Our results suggest that the presence of a food swamp is a stronger predictor of obesity rates than the absence of full-service grocery stores. We found, even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All three food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on rates of adult obesity (p values ranged from 0.00 to 0.16). Our adjustment for reverse causality, using an IV approach, revealed a stronger effect of food swamps than would have been obtained by naïve ordinary least squares (OLS) estimates. The food swamp effect was stronger in counties with greater income inequality (p < 0.05) and where residents are less mobile (p < 0.01). Based on these findings, local government policies such as zoning laws simultaneously restricting access to unhealthy food outlets and incentivizing healthy food retailers to locate in underserved neighborhoods warrant consideration as strategies to increase health equity. PMID:29135909

Gulf-Wide Information System, Environmental Sensitivity Index Swamps, Geographic NAD83, LDWF (2001) [esi_swamp_LDWF_2001

Data.gov (United States)

Louisiana Geographic Information Center — This data set contains Environmental Sensitivity Index (ESI) swamps data of coastal Louisiana. The ESI is a classification and ranking system, which characterizes...

Conservation status of crayfishes of the United States and Canada

Science.gov (United States)

Christopher A. Taylor; Melvin L. Warren; J. F. Fitzpatrick; Horton H. Hobbs; Raymond F. Jezerinac; William L. Pflieger; Henry W. Robinson

1996-01-01

The American Fisheries Society (AFS) Endangered Species Committee herein provides a list of all crayfishes (families and Cambaridae) in the United States and Canada that includes state provincial distributions; a comprehensive review of the conservation status of all taxa; and references on biology, conservation, and...

Information to support to monitoring and habitat restoration on Ash Meadows National Wildlife Refuge

Science.gov (United States)

Scoppettone, G. Gary

2013-01-01

The Ash Meadows National Wildlife Refuge staff focuses on improving habitat for the highest incidence of endemic species for an area of its size in the continental United States. Attempts are being made to restore habitat to some semblance of its pre-anthropogenic undisturbed condition, and to provide habitat conditions to which native plant and animal species have evolved. Unfortunately, restoring the Ash Meadows’ Oases to its pre-anthropogenic undisturbed condition is almost impossible. First, there are constraints on water manipulation because there are private holdings within the refuge boundary; second, there has been at least one species extinction—the Ash Meadows pool fish (Empetrichthys merriami). It is also quite possible that thermal endemic invertebrate species were lost before ever being described. Perhaps the primary obstacle to restoring Ash Meadows to its pre-anthropogenic undisturbed conditions is the presence of invasive species. However, invasive species, such as red swamp crayfish (Procambarus clarki) and western mosquitofish (Gambusia affinis), are a primary driving force in restoring Ash Meadows’ spring systems, because under certain habitat conditions they can all but replace native species. Returning Ash Meadows’ physical landscape to some semblance of its pre-anthropogenic undisturbed condition through natural processes may take decades. Meanwhile, the natural dissolution of concrete and earthen irrigation channels threatens to allow cattail marshes to flourish instead of spring-brooks immediately downstream of spring discharge. This successional stage favors non-native crayfish and mosquitofish over the native Amargosa pupfish (Cyprinodon nevadensis). Thus, restoration is needed to control non-natives and to promote native species, and without such intervention the probability of native fish reduction or loss, is anticipated. The four studies in this report are intended to provide information for restoring native fish habitat and

Long-term disturbance dynamics and resilience of tropical peat swamp forests.

Science.gov (United States)

Cole, Lydia E S; Bhagwat, Shonil A; Willis, Katherine J

2015-01-01

1. The coastal peat swamp forests of Sarawak, Malaysian Borneo, are undergoing rapid conversion, predominantly into oil palm plantations. This wetland ecosystem is assumed to have experienced insignificant disturbance in the past, persisting under a single ecologically-stable regime. However, there is limited knowledge of the past disturbance regime, long-term functioning and fundamentally the resilience of this ecosystem to changing natural and anthropogenic perturbations through time. 2. In this study, long-term ecological data sets from three degraded peatlands in Sarawak were collected to shed light on peat swamp forest dynamics. Fossil pollen and charcoal were counted in each sedimentary sequence to reconstruct vegetation and investigate responses to past environmental disturbance, both natural and anthropogenic. 3. Results demonstrate that peat swamp forest taxa have dominated these vegetation profiles throughout the last c . 2000-year period despite the presence of various drivers of disturbance. Evidence for episodes of climatic variability, predominantly linked to ENSO events, and wildfires is present throughout. However, in the last c . 500 years, burning and indicators of human disturbance have elevated beyond past levels at these sites, concurrent with a reduction in peat swamp forest pollen. 4. Two key insights have been gained through this palaeoecological analysis: (i) peat swamp forest vegetation has demonstrated resilience to disturbance caused by burning and climatic variability in Sarawak in the late Holocene, however (ii) coincident with increased fire combined with human impact c . 500 years ago, these communities started to decline. 5. Synthesis . Sarawak's coastal peat swamps have demonstrated resilience to past natural disturbances, with forest vegetation persisting through episodes of fire and climatic variability. However, palaeoecological data presented here suggest that recent, anthropogenic disturbances are of a greater magnitude

Geomorphic controls on fluvial carbon exports and emissions from upland swamps in eastern Australia.

Science.gov (United States)

Cowley, Kirsten; Looman, Arun; Maher, Damien T; Fryirs, Kirstie

2018-03-15

Temperate Highland Peat Swamps on Sandstone (THPSS) are upland wetlands, similar to fens in the Northern Hemisphere and are found at the headwaters of low-order streams on the plateaus of Eastern Australia. They are classified as endangered ecological communities under State and National legislation. Previous works have identified particular geomorphic characteristics that are important to carbon storage in these low energy sediment accumulation zones. Changes in the geomorphic structure of THPSS, such as channelisation, may have profound implications for carbon storage. To assess the effect of channelisation on carbon budgets in these ecosystems it is essential to identify and quantify differences in carbon export, emissions and stocks of carbon of intact swamps and those that have become channelised. We undertook seasonal sampling of the perched swamp aquifers and surface waters of two intact swamps and two channelised fills in the Blue Mountains of New South Wales, Australia, to investigate differences in carbon exports and emissions between the two swamp types. We found that channelised fills' mean CO 2 emissions were almost four times higher than intact swamps with mean CH 4 emissions up to five times higher. Annual fluvial carbon exports for channelised fills were up to 18 times that of intact swamps. Channelised fill exports and emissions can represent up to 2% of the total swamp carbon stocks per annum which is 40 times higher than the intact swamps. This work clearly demonstrates that changes in geomorphic structure brought about by incision and channelisation results in profound changes to the carbon storage function of THPSS. Copyright © 2017 Elsevier B.V. All rights reserved.

Fluoride bioaccumulation and toxic effects on the survival and behavior of the endangered white-clawed crayfish Austropotamobius pallipes (Lereboullet).

Science.gov (United States)

Aguirre-Sierra, Arantxa; Alonso, Alvaro; Camargo, Julio A

2013-08-01

Laboratory experiments were performed to examine the toxic effects of fluoride (F(-)) on the survival and behavior of white-clawed crayfish (Austropotamobius pallipes). Body fluoride contents (bioaccumulation) of test crayfish were also examined. No significant differences between male and female crayfish regarding mortality, escape (tail-flip) response, and fluoride bioaccumulation were detected. For mortality, 48-, 72-, 96-, 120-, 144-, 168-, and 192-h median lethal concentrations (LC50) were estimated to be 93.0, 55.3, 42.7, 36.5, 32.9, 30.6, and 28.9 mg F(-)/l, respectively. For the escape response, 48-, 72-, 96-, 120-, 144-, 168- and 192-h median effective concentrations (EC50) were estimated to be 18.4, 11.1, 8.6, 7.4, 6.7, 6.2 and 5.9 mg F(-)/l, respectively. Average food consumption in test crayfish tended to decrease with increasing water fluoride concentration with a 192-h lowest-observed effect concentration of 10.7 mg F(-)/l. These results indicate that the escape response was the most sensitive end point to fluoride toxicity followed by food consumption and mortality. Fluoride bioaccumulation in test crayfish increased with increasing water fluoride concentration and exposure time. The exoskeleton accumulated more fluoride than muscle. A comparison of the obtained results with previous data for other freshwater invertebrates shows that white-clawed crayfish are relatively tolerant to fluoride toxicity. We conclude that fluoride pollution in freshwater ecosystems should not be viewed as an important risk factor contributing to the catastrophic decrease of A. pallipes in many European countries. Our results indicate that fluoride bioaccumulation in A. pallipes might be used as a bioindicator of fluoride pollution in freshwater ecosystems where it is present.

137Cs Transfer Factor from Latosol Soil to Swamp Gabbages (Ipomea Reptans Poir)

International Nuclear Information System (INIS)

Leli-Nirwani; Yurfida; Buchori

2001-01-01

A study of 137 Cs transfer factor from Latosol soil to swamp cabbages plant has been conducted using pot treatment system with complete random design. The aim of the research is to determine transfer factor of 137 Cs from latosol soil to swamp cabbages plant. Cs-137 concentration administered was 7.5287 kBq/pot. The number of swamp cabbages planted in 137 Cs treated soil and in cannot soil respectively was 12 pots filled with 1 kg soil/pot. After harvest, the weight of dried plant was measured. Transfer factor was determined according to the accumulation of 137 Cs concentration in swamp cabbages and soil and counted using Spectrometer Gamma. It was found that is a significant difference between 137 Cs concentration in swamp cabbages planted inthe treated soil and that of control soil. Transfer factor ranges between 0.02 and 0.13 with the averageof 0.08. (author)

Coatal salt marshes and mangrove swamps in China

Science.gov (United States)

Yang, Shi-Lun; Chen, Ji-Yu

1995-12-01

Based on plant specimen data, sediment samples, photos, and sketches from 45 coastal crosssections, and materials from two recent countrywide comprehensive investigations on Chinese coasts and islands, this paper deals with China’s vegetative tidal-flats: salt marshes and mangrove swamps. There are now 141700 acres of salt marshes and 51000 acres of mangrove swamps which together cover about 30% of the mud-coast area of the country and distribute between 18°N (Southern Hainan Island) and 41 °N (Liaodong Bay). Over the past 45 years, about 1750000 acres of salt marshes and 49400 acres of mangrove swamps have been reclaimed. The 2.0×109 tons of fine sediments input by rivers into the Chinese seas form extensive tidal flats, the soil basis of coastal helophytes. Different climates result in the diversity of vegetation. The 3˜8 m tidal range favors intertidal zone development. Of over 20 plant species in the salt marshes, native Suaeda salsa, Phragmites australis, Aeluropus littoralis, Zoysia maerostachys, Imperata cylindrica and introduced Spartina anglica are the most extensive in distribution. Of the 41 mangrove swamps species, Kandelia candel, Bruguiera gymnorrhiza, Excoecaria agallocha and Avicennia marina are much wider in latitudinal distribution than the others. Developing stages of marshes originally relevant to the evolution of tidal flats are given out. The roles of pioneer plants in decreasing flood water energy and increasing accretion rate in the Changjiang River delta are discussed.

MANAGEMENT OF THE WHITE-CLAWED CRAYFISH (AUSTROPOTAMOBIUS PALLIPES IN WESTERN FRANCE: ABIOTIC AND BIOTIC FACTORS STUDY

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TROUILHE M. C.

2003-04-01

Full Text Available In France, the distribution of the white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858, is restricted, fragmented and mainly located in headwaters. To preserve this indigenous species, it is necessary to characterize its ecological requirements (water and habitat quality. With this aim in view, a two-year study is being conducted in the Deux-Sèvres department (Western France since November 2002. Nine brooks from four different catchments are monitored regularly; eight of the nine brooks harbour whiteclawed crayfish populations. Two sampling sites are surveyed per brook, the first being where the crayfish population is located and the second 2 to 3 km downstream. Physicochemical parameters (18 are measured twice monthly and biotic factors are estimated twice yearly. In this study, the I.B.G.N. (Indice Biologique Global Normalisé protocol based on the determination of macroinvertebrates was used as a biotic index of biological water quality. Results of this preliminary study on two brooks (Thouet and Verdonnière show that physico-chemical and biological data considered separately do not provide reliable information about A. pallipes ecological requirements. However, the use of multivariate analyses (Principal Component Analysis to combine abiotic and biotic factors highlights a good correlation between these parameters. Organic matter appears to be a better discriminating factor than mineral matter affecting presence or absence of the whiteclawed crayfish.

Trapping for invasive crayfish: comparisons of efficacy and selectivity of baited traps versus novel artificial refuge traps

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Green Nicky

2018-01-01

Full Text Available Non-native crayfish can dominate the invertebrate biomass of invaded freshwaters, with their high ecological impacts resulting in their populations being controlled by numerous methods, especially trapping. Although baited funnel traps (BTs are commonly used, they tend to be selective in mainly catching large-bodied males. Here, the efficacy and selectivity of BTs were tested against an alternative trapping method based on artificial refuges (ARTs that comprised of a metal base with several tubes (refuges attached. The target species was signal crayfish Pacifastacus leniusculus in an upland river in southwest England. Trapping was completed in April to October over two consecutive years. In total, 5897 crayfish were captured, with 87% captured in ARTs. Comparison of the catch per unit effort (CPUE between the trapping methods in the same 24 hour periods revealed significantly higher CPUE in ARTs than of BTs. ARTs fished for 6 consecutive days had higher catches than both methods over 24 hours. Whilst catches in BTs were significantly dominated by males (1.49M:1F, the sex ratio of catches in ARTs was 0.99M:1F. The mean carapace length of crayfish was also significantly larger in BTs (43.2 ± 0.6 mm than in ARTs (33.6 ± 0.2 mm. Thus, ARTs had higher CPUE over 24 hour and 6 day periods versus BTs and also captured a greater proportion of smaller and female individuals. These results indicate that when trapping methods are deployed for managing invasions, the use of ARTs removes substantial numbers of crayfish of both sexes and of varying body sizes.

Peat swamp forest of Thailand

Energy Technology Data Exchange (ETDEWEB)

Niyomdham, C.; Urapeepatanapong, C.; Pitayakajornwute, P. [Pikoolthong Royal Development Study Center, Bangkok (Thailand). Royal Forest Department

1996-12-31

Peat swamp forest in Thailand occurs extensively along coastal flatlands in the central and southern parts of the country and some small patches of topogenous peatland are present locally on several mountain tops of the northern region. Many have been deteriorated by recent extensive development programs. However, one large area, about 347.04 km{sup 2}, of ombrogenous peatland is still left intact in the Pru Toh Dang area where conservation activities are being strictly enforced under one of the Royal Initiative Projects. Pru Toh Dang peat consists of 5 metres of fibrous organic soil overlying pyritic marine clay. Despite an inhospitable, submerged and unstable forest floor, the floristic composition of the peat swamp forest is extremely complicated, consisting of 124 families and 470 species of which 109 families and 437 species of flowering plants, and 15 families and 33 species of ferns recorded between 1983-1989 by a team from the Forest Herbarium of the Royal Forest Department of Thailand. (orig.) (4 refs.)

Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea

International Nuclear Information System (INIS)

Simon, Olivier; Garnier-Laplace, Jacqueline

2005-01-01

At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9 ± 0.1 to 20.2 ± 9 μg/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9 ± 0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution

DISTRIBUTION, RECENT MORTALITIES AND CONSERVATION MEASURES OF CRAYFISH IN HELLENIC FRESH WATERS

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KOUTRAKIS E.

2007-04-01

Full Text Available Freshwater crayfish are found in 20 out of 53 Prefectures of Greece (38% and they form isolated populations in relatively pristine water bodies. Three indigenous crayfish species (ICS occur in Greek waters: Astacus astacus, Astacus leptodactylus and Austropotamobius torrentium, as well as one non-indigenous crayfish species (NICS Pacifastacus leniusculus. Greece represents probably the most southern natural distribution limit for A. astacus and A. torrentium in the world. Concerning NICS, P. leniusculus was imported, at least in two cases, from Sweden and Germany during the early and late 1980’s respectively, in order to replace A. astacus stocks impoverished by human activities. Recently, Cherax quadricarinatus specimens have been seen in a restaurant’s aquarium and pet shop, raising fears about uncontrolled imports of alien pet species. During our 2004-2005 survey, we found that P. leniusculus established not only a thriving population in the artificial Lake Agra (Region of Central Macedonia, but also they co-occur with A. torrentium there. It is also suspected that A. astacus may co-occur there with these two species, as three large male specimens of A. astacus were caught in a creek close to the lake. Concerning A. leptodactylus, there are three sets of preserved samples from the River Evros (state border with Turkey in Thrace today, dated back to the 19th century, but no recent information about occurrence was available. But the accidental catch of six specimens of A. leptodactylus during May 2005 in that river re-documented the occurrence of the species. Finally, a deep-dwelling A. torrentium population with bluish legs was found to live in depths up to 7,800 meters inside the Aggitis Cave in northeastern Greece. There is a lot of work to be done on geographic distribution, population dynamics, genetics, reproduction, nutrition, diseases, and farming of crayfish species in Greece. Moreover, several actions should be undertaken to

Crayfish Behavior: Observing Arthropods to Learn about Science & Scientific Inquiry

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Rop, Charles J.

2010-01-01

This is a set of animal behavior investigations in which students will practice scientific inquiry as they observe crayfish, ask questions, and discuss territoriality, social interactions, and other behaviors. In doing this, they hone their skills of observation, learn to record and analyze data, control for variables, write hypotheses, make…

REDUCING THE THREAT TO CONTROL INVASIVE SIGNAL CRAYFISH REDUCING: THE POTENTIAL USE OF PHEROMONES

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STEBBING P. D.

2003-04-01

Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States

OpenAIRE

Cooksey-Stowers, Kristen; Schwartz, Marlene B.; Brownell, Kelly D.

2017-01-01

This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data ...

Electrophysiological Investigation of Different Methods of Anesthesia in Lobster and Crayfish

Science.gov (United States)

Fregin, Torsten; Bickmeyer, Ulf

2016-01-01

Objectives In search for methods of anesthesia of crustaceans, an implanted electrode into lobster and crayfish CNS enabled us to monitor signal propagation in the nerve system of animals undergoing different protocols. Results Cooling (tap water 0°C, sea water -1,8°C) and anesthesia with MgCl2 (10%) were both discarded as anesthetic procedures because responses to external stimuli were still detectable under treatment. Contrarily, bubbling the aquarium water with CO2 can be considered a “partially successful” anesthesia, because signal propagation is inhibited but before that the animals show discomfort. The procedure of “electro-stunning” induces epileptic-form seizures in the crustacean CNS (lobster, crayfish), which overlay but do not mitigate the response to external stimuli. After several minutes the activity declines before the nervous system starts to recover. A feasible way to sacrifice lobsters is to slowly raise the water temperature (1°C min-1), as all electrical activities in the CNS cease at temperatures above ~30°C, whereas below this temperature the animals do not show signs of stress or escape behavior (e.g. tail flips) in the warming water. Conclusion CO2 is efficient to anaesthetize lobster and crayfish but due to low pH in water is stressful to the animals previous to anesthesia. Electrical stunning induces epileptiform seizures but paralyses the animals and leads to a reversible decline of nerve system activity after seizure. Electric stunning or slowly warming just before preparation may meet ethical expectations regarding anaesthesia and to sacrifice crustaceans. PMID:27642755

Effects of chronic cocaine, morphine and methamphetamine on the mobility, immobility and stereotyped behaviors in crayfish.

Science.gov (United States)

Imeh-Nathaniel, Adebobola; Rincon, Natalia; Orfanakos, Vasiliki Bessie; Brechtel, Leanne; Wormack, Leah; Richardson, Erika; Huber, Robert; Nathaniel, Thomas I

2017-08-14

The worth of crayfish as a model system for studies of addiction was not previously recognized because a drug-reward phenomenon had not been documented in this model system. In our previous experiments, we demonstrate that the crayfish natural reward pathways are sensitive to human drugs of abuse. This finding supports crayfish as a suitable model to characterize specific behaviors that are relevant in drug addiction research, and the current study builds on our previous findings. The aim of the present study was to investigate unconditioned neurobehavioral effects of repeated treatment regimens using cocaine, morphine, and methamphetamine for three consecutive days. We analyzed mobility, immobility and characterized stereotypic behaviors following intracardial infusions of 2.0μg/g or 10.0μg/g doses of cocaine, morphine, and methamphetamine for three days. The results showed that systemic cocaine, morphine, and methamphetamine increased mobility at a low dose of 2.0μg/g more effectively than a high dose of 10.0μg/g, while simultaneously showing that the high dose exerted a more prominent effect in increasing immobility. Moreover, systemic cocaine, morphine, and methamphetamine injections have discerning effects towards a group of defined unconditioned stereotyped behavioral patterns associated with each drug, rather than a shared universal behavioral effect. These findings provide insight into the behavioral and pharmacological basis responsible for the unconditioned effects of these drugs in crayfish. Copyright © 2017. Published by Elsevier B.V.

New distributional records of the stygobitic crayfish Cambarus cryptodytes (Decapoda: Cambaridae) in the Floridan Aquifer System of southwestern Georgia

Science.gov (United States)

Fenolio, Dante B.; Niemiller, Matthew L.; Gluesenkamp, Andrew G.; Mckee, Anna; Taylor, Steven J.

2017-01-01

Cambarus cryptodytes (Dougherty Plain Cave Crayfish) is an obligate inhabitant of groundwater habitats (i.e., a stygobiont) with troglomorphic adaptations in the Floridan aquifer system of southwestern Georgia and adjacent Florida panhandle, particularly in the Dougherty Plain and Marianna Lowlands. Documented occurrences of Dougherty Plain Cave Crayfish are spatially distributed as 2 primary clusters separated by a region where few caves and springs have been documented; however, the paucity of humanly accessible karst features in this intermediate region has inhibited investigation of the species' distribution. To work around this constraint, we employed bottle traps to sample for Dougherty Plain Cave Crayfish and other groundwater fauna in 18 groundwater-monitoring wells that access the Floridan aquifer system in 10 counties in southwestern Georgia. We captured 32 Dougherty Plain Cave Crayfish in 9 wells in 8 counties between September 2014 and August 2015. We detected crayfish at depths ranging from 17.9 m to 40.6 m, and established new county records for Early, Miller, Mitchell, and Seminole counties in Georgia, increasing the number of occurrences in Georgia from 8 to 17 sites. In addition, a new US Geological Survey (USGS) Hydrologic Unit Code 8 (HUC8) watershed record was established for the Spring Creek watershed. These new records fill in the distribution gap between the 2 previously known clusters in Georgia and Jackson County, FL. Furthermore, this study demonstrates that deployment of bottle traps in groundwater-monitoring wells can be an effective approach to presence—absence surveys of stygobionts, especially in areas where surface access to groundwater is limited.

Neuromodulation of activity-dependent synaptic enhancement at crayfish neuromuscular junction.

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Qian, S M; Delaney, K R

1997-10-17

Action potential-evoked transmitter release is enhanced for many seconds after moderate-frequency stimulation (e.g. 15 Hz for 30 s) at the excitor motorneuron synapse of the crayfish dactyl opener muscle. Beginning about 1.5 s after a train, activity-dependent synaptic enhancement (ADSE) is dominated by a process termed augmentation (G.D. Bittner, D.A. Baxter, Synaptic plasticity at crayfish neuromuscular junctions: facilitation and augmentation, Synapse 7 (1991) 235-243'[4]; K.L. Magleby, Short-term changes in synaptic efficacy, in: G.M. Edelman, L.E. Gall, C.W. Maxwell (Eds.), Synaptic Function, John Wiley and Sons, New York, 1987, pp. 21-56; K.L. Magleby; J.E. Zengel, Augmentation: a process that acts to increase transmitter release at the frog neuromuscular junction, J. Physiol. (Lond.) 257 (1976) 449-470) which decays approximately exponentially with a time constant of about 10 s at 16 degrees C, reflecting the removal of Ca2+ which accumulates during the train in presynaptic terminals (K.R. Delaney, D.W. Tank, R.S. Zucker, Serotonin-mediated enhancement of transmission at crayfish neuromuscular junction is independent of changes in calcium, J. Neurosci. 11 (1991) 2631-2643). Serotonin (5-HT, 1 microM) increases evoked and spontaneous transmitter release several-fold (D. Dixon, H.L. Atwood, Crayfish motor nerve terminal's response to serotonin examined by intracellular microelectrode, J. Neurobiol. 16 (1985) 409-424; J. Dudel, Modulation of quantal synaptic release by serotonin and forskolin in crayfish motor nerve terminals, in: Modulation of Synaptic Transmission and Plasticity in Nervous Systems, G. Hertting, H.-C. Spatz (Eds.), Springer-Verlag, Berlin, 1988; S. Glusman, E.A. Kravitz. The action of serotonin on excitatory nerve terminals in lobster nerve-muscle preparations, J. Physiol. (Lond.) 325 (1982) 223-241). We found that ADSE persists about 2-3 times longer after moderate-frequency presynaptic stimulation in the presence of 5-HT. This slowing of the

Stress reaction in crayfish: chlorides help to withstand stress in high nitrite concentration conditions – preliminary study

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Kozák P.

2011-06-01

Full Text Available A non-invasive method of recording cardiac activity (heart rate – HR and stress reaction (stress index – SI was used to understand the immediate and ongoing stress reaction of crayfish to the chemical stimuli. This method detects changes in the shape and amplitude parameters of the response to the stress factors, which characterized the crayfish functional state. Experimental animals (Astacus leptodactylus were divided to the two groups with (400 mg·L-1 Cl− and without added chlorides and then exposed to a stepwise increased level of nitrite to the final (sublethal-lethal concentration of 60 mg·L-1 N-NO\\hbox{$_{2}^{-}$}−2 within 24 hours. The course of crayfish reaction was evident and provided information about their reaction to the sublethal-lethal concentration over time. As expected, a less prominent stress reaction was detected in the group with chlorides. The non-invasive method successfully evaluated the sensing of chemical stimuli in water through HR and SI changes.

Evaluation of different marking methods for spiny-cheek crayfish (Orconectes limosus

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Buřič M.

2008-10-01

Full Text Available Different methods of marking were evaluated for Orconectes limosus (CL = carapace length, 12–37 mm under laboratory conditions: the use of passive integrated transponders, visible implant elastomers, visible implant alphanumeric tags, and cauterization. High survival (> 90% was obtained with all methods tested. Tag retention and readability were evaluated immediately after marking, before and after ecdysis, with moult increments and number of moults been recorded. Marking using cauterization negatively affects the percent moult increment (PMI of crayfish. The average PMI of 15 ± 0.88% did not differ between males (15 ± 1.41 mm and females (15 ± 1.12 mm. It was found that PMI gradually decreased with an increase in CL. Sixty-one moults were observed, with 12 crayfish (6 juveniles and 6 adults presenting two moults. Time between moults varied from 3 to 7 weeks. CL was increased with over 28 ± 2.68% due to two moults. Three females moulted twice after successful hatching and carrying of juveniles.

Swamp land optimization in supporting food security and enhancing farmers welfare in South Sumatra Indonesia

Science.gov (United States)

Herwenita; Hutapea, Y.

2018-02-01

Swamp land in Indonesia spread in Sumatra, Kalimantan and West Papua. In Sumatra the largest swamp land area is located in South Sumatera Province. Unfortunately only few of the areas have been utilized due to its fragility, in which farmers could only cultivate rice on it once a year. The purpose of this paper is to develop a feasible farming pattern in swamp land to help farmers and practitioners in optimizing it by managing its water level. Shallow and mid swamp land can be cultivated using rotation model of crops (rice, corn, cassava), horticulture (cucumber, long beans, watermelon etc), fish farming (catfish, snake head fish, tilapia), and duck farming, whereas submergence tolerant rice varieties can be cultivated alternating with fish farming in deep swamp land. This study shows that such swamp land management is financially feasible showing by its positive NPV value, BCR value is above 1.00, and IRR value is greater than the interest rate. Therefore, implementation of this farming pattern is expected to increase farmers’ income and household food supply as well as village food supply.

Pen Branch Delta and Savannah River Swamp Hydraulic Model

International Nuclear Information System (INIS)

Chen, K.F.

1999-01-01

The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions

Effects of dietary propolis on the number and size of pleopadal egg, oxidative stress and antioxidant status of freshwater crayfish (Astacus leptodactylus Eschscholtz).

Science.gov (United States)

Mişe Yonar, Serpil; Köprücü, Kenan; Yonar, Muhammet Enis; Silici, Sibel

2017-09-01

Four different crayfish diets; control, E1, E2 and E3, respectively containing 0, 1, 2 and 4% propolis, were tested to determine the effects of dietary propolis on the number and size of pleopadal egg, and malondialdehyde (MDA) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities in the freshwater crayfish (Astacus leptodactylus). The crayfish were kept at 9.6±5.3°C water temperature and fed three times daily during a six month period The pleopodal egg number (from 7 to 9) produced per gram of the body weight and total pleopodal egg number (from 201 to 263) significantly increased (Pegg size (from 3.22mm to 2.76mm). MDA level significantly (Pegg. The dietary propolis improves reproductive efficiency in the crayfish and decreases the oxidative stress under controlled hatchery conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Mineral uptake by taro (colocasla esculenta) in swamp agroecosystem following gramoxone paraquat herbicide spraying

International Nuclear Information System (INIS)

Nashriyah Mat; Mazleha Maskin; Abdul Khalik Wood

2006-01-01

Mineral elemental uptake by Colocasia esculenta growing in swamp agroecosystem was studied following 14, 18 or 28 months of field spraying (MAT, months after treatment) with herbicide Gramoxone paraquat. In overall, Al (68226.67 ± 24066.56 μ/g dw) was the major element in riverine alluvial swamp soil, followed by micronutrient Fe (22280.00 ± 6328.87 μ/g dw). Concentration of macronutrient K (20733.33 ± 7371.82, μ/g dw) was the highest in swamp taro leaf followed by macronutrient Ca (7050.00 ± 3767.26 μ/g dw). In overall, the order of importance of the average mineral concentration in swamp taro leaf was K > Ca > Mn > Al > Na > Fe > Zn > Br > Co. However at 14 MAT, the order of importance of mineral content concentration in swamp taro leaf was K > Ca > Al > Na > Mn > Fe > Zn > Br > Co. At 18 MAT, the order of importance of mineral content concentration in swamp taro leaf was K > Ca > Mn > Al > Fe > Na > Zn > Br > Co. At 28 AMT, the order of importance of mineral content concentration in swamp taro leaf was K > Ca > Mn > Fe > Al > Zn > Na > Br > Co. In overall, the average order of importance of mineral elemental uptake or the soil plant transfer coefficient was Mn > K > Na > Zn > Co > Fe > Al; similar with the order at 28 MAT However, at 14 MAT the order of importance of the soil plant transfer coefficient was different at Mn > K > Na > Co > Zn > Al > Fe. (Author)

Magruder Park Swamp

Science.gov (United States)

Hotchkiss, N.; Uhler, F.M.

1967-01-01

The last Tuesday in August, between five-thirty and seven in the evening, we zigzaged through this glorious jungle, attended by a family of Wood Pewees for whom we seemed to be stirring up a feast of flying insects. There was gentle background music by Mole Crickets. A few steps in from the playing field and we were out of sight in ten-foot-high Cattails. All through, we met -- as high as we, or higher--clumped Cinnamon Ferns, deep-rose Joe Pye Weed, and orange, pendent flowers of Jewelweed (first cousins to Balsam and Sultana). Here and there were soft, white spikes of Canadian Burnet, a rare plant hereabouts, and deep purple Ironweed. Dense-foliaged Hempweed climbed over bushes and up small trees, filling the air with its delicate fragrance. Arrowleaf Tear-thumb snatched at us with tiny prongs on its angled stems. Once in a while we tripped over huge sedge tussocks, half-hidden in the tangle. A few times we steered around a small bush of Poison Sumac. The next day We remembered seeing ninety kinds of plants on this hasty trip. Skunk Cabbage leaves recalled April, when a person, from the edge of the lawn, could see huge clumps of them all the way across the swamp. The sky had been washed by last week's downpours; scattered Gums were reddening; and Maples were getting ready for crimson beauty a month from now. There wasn't a mosquito! (Ed. Note.-The Hyattsville City Council is taking pains to preserve this interesting swamp.)

Growth, yield, plant quality and nutrition of basil (Ocimum basilicum L. under soilless agricultural systems

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Subhrajit Saha

2016-12-01

Full Text Available Traditional agricultural systems are challenged by globally declining resources resulting from climate change and growing population. Alternative agricultural practices such as aquaponics (includes crop plant and aquatic species and hydroponics (includes crop plant only have the potential to generate high yield per unit area using limited land, water, and no soil. A soilless agricultural study was conducted at the Georgia Southern University, Statesboro, GA, USA from August to November, 2015. The growth, yield, quality, and nutrition of basil (Ocimum basilicum L. cultivar Aroma 2, were compared between aquaponic and hydroponic systems using crayfish (Procambarus spp. as the aquatic species. Non-circulating floating raft systems were designed using 95 L polyethylene tanks. Equal amounts of start-up fertilizer dose were applied to both systems. The objective was to understand how the additional nutritional dynamics associated with crayfish influence the basil crop. Both fresh and dry basil plant weights were collected after harvest, followed by leaf nutrient analysis. Leaf chlorophyll content, water pH, nitrogen and temperature were measured periodically. Aquaponic basil (AqB showed 14%, 56%, and 65% more height, fresh weight, and dry weight, respectively, compared to hydroponic basil (HyB. It is logical to assume that crayfish waste (excreta and unconsumed feed has supplied the additional nutrients to AqB, resulting in greater growth and yield. The chlorophyll content (plant quality or leaf nutrients, however, did not differ between AqB and HyB. Further research is needed to investigate aquaponic crayfish yield, overall nutritional dynamics, cost-benefit ratio, and other plant characteristics under soilless systems.

Differences found in the macroinvertebrate community composition in the presence or absence of the invasive alien crayfish, Orconectes hylas

Science.gov (United States)

Freeland-Riggert, Brandye T.; Cairns, Stefan H.; Poulton, Barry C.; Riggert, Chris M.

2016-01-01

Introductions of alien species into aquatic ecosystems have been well documented, including invasions of crayfish species; however, little is known about the effects of these introductions on macroinvertebrate communities. The woodland crayfish (Orconectes hylas (Faxon)) has been introduced into the St. Francis River watershed in southeast Missouri and has displaced populations of native crayfish. The effects of O. hylas on macroinvertebrate community composition were investigated in a fourth-order Ozark stream at two locations, one with the presence of O. hylas and one without. Significant differences between sites and across four sampling periods and two habitats were found in five categories of benthic macroinvertebrate metrics: species richness, percent/composition, dominance/diversity, functional feeding groups, and biotic indices. In most seasons and habitat combinations, the invaded site had significantly higher relative abundance of riffle beetles (Coleoptera: Elmidae), and significantly lower Missouri biotic index values, total taxa richness, and both richness and relative abundance of midges (Diptera: Chironomidae). Overall study results indicate that some macroinvertebrate community differences due to the O. hylas invasion were not consistent between seasons and habitats, suggesting that further research on spatial and temporal habitat use and feeding ecology of Ozark crayfish species is needed to improve our understanding of the effects of these invasions on aquatic communities.

The Productivity and Natural Increase of Swamp Buffalo in District Malang

Science.gov (United States)

Budiarto, A.; Ciptadi, G.

2018-02-01

The purpose of this research was to collect the basic information needed to develop a sustainable breeding program, which includes the potential for production and reproduction of buffaloes. This research was conducted on swamp buffalo in Malang Regency East Java. The research method used was survey method. Primary data was obtained from direct observation on 323 tails owned by 98 breeders. Variables observed were population growth and reproductive performance. The data obtained were analyzed descriptively. The result showed that the initial population study of swamp Buffaloes in Malang as many as 1155 with male and female ratio 1: 2. The ratios of male and female swamp Buffalo 20 percent male and 80 percent female. Overall, the buffalo reproduction performance was still low. Service per conception 2.06 ± 0.88; Anestrus Postpartum 7.46 ± 3.83 months; calving interval distance 17.82 ± 4.86 months; 20.43 % birth rate and 4.33% mortality rate of Natural Increase (NI) population was about 16,1%. In conclusion, the value of NI of swamp Buffalo in Malang Regency is still low. To increase buffalo productivity, buffalo breeding program is continuously based on reproduction control.

Logged peat swamp forest supports greater macrofungal biodiversity than large-scale oil palm plantations and smallholdings.

Science.gov (United States)

Shuhada, Siti Noor; Salim, Sabiha; Nobilly, Frisco; Zubaid, Akbar; Azhar, Badrul

2017-09-01

Intensive land expansion of commercial oil palm agricultural lands results in reducing the size of peat swamp forests, particularly in Southeast Asia. The effect of this land conversion on macrofungal biodiversity is, however, understudied. We quantified macrofungal biodiversity by identifying mushroom sporocarps throughout four different habitats; logged peat swamp forest, large-scale oil palm plantation, monoculture, and polyculture smallholdings. We recorded a total of 757 clusters of macrofungi belonging to 127 morphospecies and found that substrates for growing macrofungi were abundant in peat swamp forest; hence, morphospecies richness and macrofungal clusters were significantly greater in logged peat swamp forest than converted oil palm agriculture lands. Environmental factors that influence macrofungi in logged peat swamp forests such as air temperature, humidity, wind speed, soil pH, and soil moisture were different from those in oil palm plantations and smallholdings. We conclude that peat swamp forests are irreplaceable with respect to macrofungal biodiversity. They host much greater macrofungal biodiversity than any of the oil palm agricultural lands. It is imperative that further expansion of oil palm plantation into remaining peat swamp forests should be prohibited in palm oil producing countries. These results imply that macrofungal distribution reflects changes in microclimate between habitats and reduced macrofungal biodiversity may adversely affect decomposition in human-modified landscapes.

Performance measures for a Mississippi River reintroduction into the forested wetlands of Maurepas Swamp

Science.gov (United States)

Krauss, Ken W.; Shaffer, Gary P.; Keim, Richard F.; Chambers, Jim L.; Wood, William B.; Hartley, Stephen B.

2017-06-09

The use of freshwater diversions (river reintroductions) from the Mississippi River as a restoration tool to rehabilitate Louisiana coastal wetlands has been promoted widely since the first such diversion at Caernarvon became operational in the early 1990s. To date, aside from the Bonnet Carré Spillway (which is designed and operated for flood control), there are only four operational Mississippi River freshwater diversions (two gated structures and two siphons) in coastal Louisiana, and they all target salinity intrusion, shellfish management, and (or) the enhancement of the integrity of marsh habitat. River reintroductions carry small sediment loads for various design reasons, but they can be effective in delivering fresh­water to combat saltwater intrusion and increase the delivery of nutrients and suspended fine-grained sediments to receiving wetlands. River reintroductions may be an ideal restoration tool for targeting coastal swamp forest habitat; much of the area of swamp forest habitat in coastal Louisiana is undergo­ing saltwater intrusion, high rates of submergence, and lack of riverine flow leading to reduced concentrations of important nutrients and suspended sediments, which sustain growth and regeneration, help to aerate swamp soils, and remove toxic compounds from the rhizosphere.The State of Louisiana Coastal Protection and Restora­tion Authority (CPRA) has made it a priority to establish a small freshwater river diversion into a coastal swamp forest located between Baton Rouge and New Orleans, Louisiana, to reintroduce Mississippi River water to Maurepas Swamp. While a full understanding of how a coastal swamp forest will respond to new freshwater loading through a Mississippi River reintroduction is unknown, this report provides guidance based on the available literature for establishing performance measures that can be used for evaluating the effectiveness of a Mississippi River reintroduction into the forested wetlands of Maurepas Swamp

Throughfall and stemflow dynamics in a riparian cedar swamp: possible ecohydrological feedbacks

Science.gov (United States)

Duval, T. P.

2012-12-01

Partitioning of rainfall through forest canopies as throughfall and stemflow have deservedly been the subject of much research in the past; however, very little is known about the fluxes of water and solutes through forested wetland communities. Temperate swamps are characterized by intermittent canopy coverage, with areas that are denser than upland forests of similar species, but also contain canopy gaps of meadow and marsh communities,. Understanding the role of vegetation on the distribution of precipitation in these ecosystems is necessary to effectively constrain water balance estimates and predict possible community responses to shifting climate regimes. This study examines throughfall, stemflow, and interception dynamics in a riparian cedar swamp in Alliston, Ontario, Canada over the 2012 growing season. Throughfall averaged 76 % of above-canopy rainfall; however, there were spatial-magnitude interaction variations within the swamp. For events less than 20 mm, between 17 and 75 % of the measured swamp floor received greater depth of rain than above the canopy, whereas for events greater than 20 mm only between 2 and 23 % of the sampled swamp floor received more water than the actual event. The observed spatial variability in throughfall was not related to leaf area index, suggesting remote sensing modelling efforts may not be an accurate method for quantification of wetland precipitation dynamics. Stemflow along the predominantly cedar trees averaged 5 %; therefore, net precipitation on a seasonal basis in this cedar swamp was 81 % of above canopy rainfall. Throughfall DOC and total nitrogen concentrations averaged 31 and 2.2 mg/L, respectively, with stemflow DOC and TN concentrations averaging 109 and 6.5 mg/L, respectively. These values are much higher than reported for upland forest species. In general, throughfall magnitudes increased and solute concentrations decreased with increasing distance from the existing forest boles. The delivery of high

Circadian rhythm in melatonin release as a mechanism to reinforce the temporal organization of the circadian system in crayfish.

Science.gov (United States)

Mendoza-Vargas, Leonor; Báez-Saldaña, Armida; Alvarado, Ramón; Fuentes-Pardo, Beatriz; Flores-Soto, Edgar; Solís-Chagoyán, Héctor

2017-06-01

Melatonin (MEL) is a conserved molecule with respect to its synthesis pathway and functions. In crayfish, MEL content in eyestalks (Ey) increases at night under the photoperiod, and this indoleamine synchronizes the circadian rhythm of electroretinogram amplitude, which is expressed by retinas and controlled by the cerebroid ganglion (CG). The aim of this study was to determine whether MEL content in eyestalks and CG or circulating MEL in hemolymph (He) follows a circadian rhythm under a free-running condition; in addition, it was tested whether MEL might directly influence the spontaneous electrical activity of the CG. Crayfish were maintained under constant darkness and temperature, a condition suitable for studying the intrinsic properties of circadian systems. MEL was quantified in samples obtained from He, Ey, and CG by means of an enzyme-linked immunosorbent assay, and the effect of exogenous MEL on CG spontaneous activity was evaluated by electrophysiological recording. Variation of MEL content in He, Ey, and CG followed a circadian rhythm that peaked at the same circadian time (CT). In addition, a single dose of MEL injected into the crayfish at different CTs reduced the level of spontaneous electrical activity in the CG. Results suggest that the circadian increase in MEL content directly affects the CG, reducing its spontaneous electrical activity, and that MEL might act as a periodical signal to reinforce the organization of the circadian system in crayfish.

Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

Science.gov (United States)

Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

2014-01-01

Crayfishes and other freshwater aquatic fauna are particularly at risk globally due to anthropogenic demand, manipulation and exploitation of freshwater resources and yet are often understudied. The Ozark faunal region of Missouri and Arkansas harbours a high level of aquatic biological diversity, especially in regard to endemic crayfishes. Three such endemics, Orconectes eupunctus,Orconectes marchandi and Cambarus hubbsi, are threatened by limited natural distribution and the invasions of Orconectes neglectus.

CONFIRMATION OF OCCURRENCE OF THE NARROW-CLAWED CRAYFISH ? STACUS LEPTODACTYLUS ESCHSCHOLTZ, 1823 IN THE RIVER EVROS IN GREECE

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PERDIKARIS C.

2007-04-01

Full Text Available The narrow-clawed crayfish Astacus leptodactylus Eschscholtz, 1823, is widely distributed in eastern European and western Asian countries. However, species presence in Greece was documented only by limited museum conserved specimens dating back to 1893. Recently (May 2005 several crayfish were captured in the Evros River (close to city of Didimotiho and these were identified as A. leptodactylus. The present work confirms the presence of A. leptodactylus in the Evros River still hundred and twelve years later and introduces the possibility of A. leptodactylus being indigenous to Greece.

Wastewater treatment by a natural wetland: the Nakivubo swamp, Uganda : processes and implications

NARCIS (Netherlands)

Kansiime, F.; Nalubega, M.

1999-01-01

An investigation to assess the capacity of the Nakivubo swamp, Kampala-Uganda (which has been receiving partially treated sewage from the city for more than 30 years now), to remove nutrients and pathogens was carried out. The aim of the study was to evaluate the potential of this swamp to

Changes in Species Composition in Alder Swamp Forest Following Forest Dieback

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Remigiusz Pielech

2018-06-01

Full Text Available It is generally hypothesized that forest dieback is a characteristic of alder swamp forests (alder carrs, Alnion glutinosae alliance. Different internal and external factors may trigger this process, including human disturbance, changes in river discharge, unusually severe and prolonged flooding, terminal age of an even-aged alder forest (ca. 100–150 years and others. Although forest dieback in this type of forest may cause major changes in environmental conditions, the influence of this change on the floristic composition has not been well recognized. The study aimed to detect any possible changes in floristic variation in alder swamp forest following forest dieback. Vegetation plots in alder swamp forests affected by forest dieback were resurveyed 20 years after a previous study. PERMANOVA was used to test the significance of the compositional change and nonmetric multidimensional scaling (NMDS with passively fitted means of the Ellenberg’s Indicator Values were used to interpret its ecological meaning. In addition, different structural and diversity indices were compared, including species richness, percentage cover of vegetation layers, Shannon and Simpson diversity and evenness. Finally, we analyzed changes in the frequency of vascular plant species using Chi square tests. We recorded clear and significant compositional changes following alder swamp forest dieback. This change was most related to the gradient of moisture, followed by the gradients of light and temperature. The analysis of the individual species showed that the species of hummocks declined, while the species of hollows increased. Moreover, the current communities are dominated by some hydrophytes that were not recorded 20 years ago. Forest dieback resulted in profound changes in the hydrological regime. The observed changes are consistent with a model of cyclic succession as proposed for alder swamps. In addition, we conclude that the natural forest dynamics have to be

Producer farmer’s sovereignty in dry land and swamps areas

Science.gov (United States)

Suhaeti, RN; Wahyuni, S.

2018-01-01

Farmers could perform their farming if they have sovereignty on their farming production inputs and marketing. Suboptimal land, such as dry land and swamps areas have good prospect if applying appropriate technologies. A research in 2015, on status of farmers’ sovereignty, had been conducted in Piani and North Candi Laras Subdistricts, Tapin District, South Borneo Province, representing swamp land and dry land respectively. Data and information were obtained through interviewing related agencies at provincial and district levels and 30 units of farmer’s households. The primary and secondary data were analyzed descriptively. The research results showed that farmers in swamps and dry land were categorized as large farmers and had sovereignty over the land and production. Water shortage and excessive in both land types could be overcome by giving access on appropriate technology such as programs making farmers improve their farming techniques and providing levees. In addition, land certification program, farming expansion and constructing new irrigated lowland were also some efforts to improve farmers’ sovereignty. It was crucial to identify and improve farmer’s sovereignty indicators through research in larger sites and samples.

EVALUATION OF THE AMERICAN WATERWEED (ELODEA CANADENSIS MICHX. AS SUPPLEMENTAL FOOD FOR THE NOBLE CRAYFISH, ASTACUS ASTACUS

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D’AGARO E.

2004-01-01

Full Text Available We conducted a preliminary study to evaluate the capacity of summerling Astacus astacus to consume the American waterweed (Elodea canadensis Michx..under artificial rearing conditions. Summerling A. astacus (initial b.w.: 0.32 ± 0.02 g were cultured (50 crayfish/m2 in 600l tanks for 89 days. The experimental design was composed of three treatments as follows: control diet (D (crude protein: 40.9% DM; ether extract: 7.4% DM, elodea (E (crude protein: 25.8% DM; ether extract: 1.4% DM and control diet + elodea (D + E with three replicates per treatment. Temperature, dissolved oxygen, and other water parameters were measured weekly (T: 20.1°C; O2: 7.2 mg/l; pH: 7.5; N-NH4: 0.05 mg/l; N-NO2: 0.01 mg/l; N-NO3: 29.9 mg/l. The relative growth rate was significantly (P < 0.01 higher in treatment D + E (195% and D (143% than in E (65%. The reduced growth observed in crayfish fed elodea only can probably be due to the lower dietary lipid level of the plant respect to the standard crayfish requirements. At the end of the experiment, the survival rate of A. astacus was higher (P < 0.05 for the treatment D + E (87% and D (81%, compared to E (56%. Our results suggest that E. canadensis can be used as a non-expensive supplemental food in order to increase growth and survival in summerling noble crayfish. They also showed that A. astacus has the potential to consume this macrophyte in nature.

The Use of Fresh Cogongrass as Transportation Media with Level Dry System for Broodstock of Crayfish on Various Old Time

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Ferdinand Hukama Taqwa

2015-01-01

Full Text Available The research was to determine the effect of the use of fresh cogongrass as media packaging filler on survival rate of broodstock of crayfish that transported with level dry system for 24, 48, dan 72 hours which randomized completely design experiment. The research preparation were media preparation of pond water, preparation of filler material and preparation of experimental animal (3 days adaptation after arrived from producer and starvation for 24 hours. The major research were anestetion of broodstock of crayfish with direct sock of low temperature at 12oC for ±5 minutes, transportation experiment of broodstock with fresh cogongrass as material filler. The result showed that the use of fresh cogongrass on various old time of dry level system has a significantly different to time of recovery and survival rate of broodstock of crayfish after tranforted. The fastest time of recovery was 89.55 seconds for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. The survival rate after tranported the highest was 98.89% for 24 hours transportation and significantly different with time of transportation for 48 hours and 72 hours. This research showed that the use of fresh cogongrass as material packaging filler of dry level system was still effective until 48 hours.Keywords: afresh cogongrass, broodstock of crayfish, various old time transportation, level dry system

Comparative Ultrastructure and Carbohydrate Composition of Gastroliths from Astacidae, Cambaridae and Parastacidae Freshwater Crayfish (Crustacea, Decapoda

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Gérard Alcaraz

2012-12-01

Full Text Available Crustaceans have to cyclically replace their rigid exoskeleton in order to grow. Most of them harden this skeleton by a calcification process. Some decapods (land crabs, lobsters and crayfish elaborate calcium storage structures as a reservoir of calcium ions in their stomach wall, as so-called gastroliths. For a better understanding of the cyclic elaboration of these calcium deposits, we studied the ultrastructure of gastroliths from freshwater crayfish by using a combination of microscopic and physical techniques. Because sugars are also molecules putatively involved in the elaboration process of these biomineralizations, we also determined their carbohydrate composition. This study was performed in a comparative perspective on crayfish species belonging to the infra-order Astacidea (Decapoda, Malacostraca: three species from the Astacoidea superfamily and one species from the Parastacoidea superfamily. We observed that all the gastroliths exhibit a similar dense network of protein-chitin fibers, from macro- to nanoscale, within which calcium is precipitated as amorphous calcium carbonate. Nevertheless, they are not very similar at the molecular level, notably as regards their carbohydrate composition. Besides glucosamine, the basic carbohydrate component of chitin, we evidenced the presence of other sugars, some of which are species-specific like rhamnose and galacturonic acid whereas xylose and mannose could be linked to proteoglycan components.

Development of crayfish bio-based plastic materials processed by small-scale injection moulding.

Science.gov (United States)

Felix, Manuel; Romero, Alberto; Cordobes, Felipe; Guerrero, Antonio

2015-03-15

Protein has been investigated as a source for biodegradable polymeric materials. This work evaluates the development of plastic materials based on crayfish and glycerol blends, processed by injection moulding, as a fully biodegradable alternative to conventional polymer-based plastics. The effect of different additives, namely sodium sulfite or bisulfite as reducing agents, urea as denaturing agent and L-cysteine as cross-linking agent, is also analysed. The incorporation of any additive always yields an increase in energy efficiency at the mixing stage, but its effect on the mechanical properties of the bioplastics is not so clear, and even dampened. The additive developing a greater effect is L-cysteine, showing higher Young's modulus values and exhibiting a remnant thermosetting potential. Thus, processing at higher temperature yields a remarkable increase in extensibility. This work illustrates the feasibility of crayfish-based green biodegradable plastics, thereby contributing to the search for potential value-added applications for this by-product. © 2014 Society of Chemical Industry.

Floristic and phytosociological analysis of palm swamps in the central part of the Brazilian savanna

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Isa Lucia de Morais Resende

2013-03-01

Full Text Available We analyzed the floristics and phytosociology of three palm swamps in the municipality of Bela Vista de Goiás, located in the state of Goiás, Brazil, in the central part of the Brazilian savanna (Cerrado. The floristic surveys were conducted monthly from May 2008 to April 2009, and 310 species were recorded (seven bryophytes, 15 ferns and 288 angiosperms. Bryophytes belonged to five genera and five families; ferns belonged to nine genera and nine families; and angiosperms belonged to 134 genera and 45 families. The angiosperm families with the highest species richness were Poaceae, Cyperaceae, Asteraceae, Eriocaulaceae, Xyridaceae, Lentibulariaceae, Melastomataceae, Rubiaceae and Fabaceae. The palm swamps were divided into three zones of increasing humidity: edge, middle and core. The number of species was higher in the middle than at the edge and the core. The families with the highest cover values were Cyperaceae, Melastomataceae, Arecaceae and Poaceae. Although the palm swamps had been disturbed to varying degrees, those disturbances did not affect the flora in the middle or the core. Floristic similarity was high between these two zones within a given palm swamp and low between the edges of different palm swamps.

A multigear protocol for sampling crayfish assemblages in Gulf of Mexico coastal streams

Science.gov (United States)

William R. Budnick; William E. Kelso; Susan B. Adams; Michael D. Kaller

2018-01-01

Identifying an effective protocol for sampling crayfish in streams that vary in habitat and physical/chemical characteristics has proven problematic. We evaluated an active, combined-gear (backpack electrofishing and dipnetting) sampling protocol in 20 Coastal Plain streams in Louisiana. Using generalized linear models and rarefaction curves, we evaluated environmental...

Interactions between crayfish, benthic invertebrates, macrophyte roots and sediment in a littoral zone

Czech Academy of Sciences Publication Activity Database

Ságová-Marečková, Markéta

2002-01-01

Roč. 155, č. 4 (2002), s. 645-665 ISSN 0003-9136 Grant - others:GA the Center for Limnology of the UW-Madison(XX) BSR8514330 Institutional research plan: CEZ:AV0Z5020903 Keywords : predation * food * crayfish Subject RIV: EE - Microbiology, Virology Impact factor: 1.195, year: 2002

ROUNDTABLE SESSION 2B: NATIONAL INTERACTIONS BETWEEN NON-INDIGENOUS AND INDIGENOUS CRAYFISH SPECIES

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GHERARDI F.

2002-07-01

Full Text Available The main object of the present essay is to summarise some aspects underlying the interactions between non-indigenous (NICS and indigenous (ICS crayfish species. The discussion has been also extended to the effects exercised by NICS on the natural habitats they occupy. While doing research on the dyads NICS/ICS, one starting point is to extrapolate common traits that make NICS good invaders from the analysis of their biology, ecology and ethology and the comparison with indigenous species. A subsequent step is to switch attention to the understanding of the characteristics that make ecosystems less vulnerable to invasions and then to analyse both the complex interactions of invaders and target communities and the negative and positive impacts exerted by NICS on the occupied habitats. Examples from Sweden, Britain, and Italy have shown that NICS can replace the native species by a combination of several interacting mechanisms. Besides the transmission of the crayfish plague fungus, mechanisms into action include mostly competitive interference, but also diverse life history traits, recruitment failure, differential susceptibility to predation, and reproductive interference. It has been claimed that invasion theory is full of rules of thumb that, having no precise predictive powers, are thus useless to guide reliable public policy. The solution of the prediction problem requires an in-depth study of every potential invader and target community, trespassing the boundaries among disciplines and having a look at crayfish as a whole and not a single entity. The expectation is thus the return to precise and clear empirical generalisations that can be most useful to develop management strategies.

Tritium uptake kinetics in crayfish (Orconectes immunis)

International Nuclear Information System (INIS)

Patrick, P.H.

1985-06-01

Uptake of tritiated water (HTO) by Orconectes immunis was investigated under laboratory conditions. Tritium uptake in the tissue-free water fraction (TFWT) was described using an exponential model. When steady-state was reached, the ratio of TFWT to HTO was approximately 0.9. Uptake of tritium in the organically-bound fraction (OBT) proceeded slowly, and had not reached steady-state after 117 days of culture. Although steady-state was never reached, the maximum observed ration of OBT to TFWT in whole animals was approximately 0.6. However, this ratio exceeded unity in the exoskeleton. Specific activity ratios of OBT between crayfish and lettuce (food source) were less than or at unity for various test conditions

Stone crayfish in the Czech Republic: how does its population density depend on basic chemical and physical properties of water?

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Vlach P.

2013-03-01

Full Text Available The stone crayfish (Austropotamobius torrentium Schrank is one of the two native crayfish species in the Czech Republic. The populations as well as physical and chemical parameters of water (pH, conductivity, dissolved oxygen, undissolved particles, NH3, NH4+, NO2−, NO3−, phosphorus, Ca2+ and SO42 −  of 33 streams were examined to find the ecological plasticity of this crayfish and some relations between these parameters and population densities. The mentioned parameters often significantly varied at the sites. Two approaches were applied to find relations between these parameters and observed abundance. At first, the observed streams were compared using RDA (streams  ×  physical-chemical parameters. No significance was found while testing relationship between the streams grouped along the 1st axis of model and the observed abundances of stone crayfish. However, some correlations between abundance and conductivity, calcium, nitrates and sulphates were found using polynomial regression. These relationships are explicable in terms of mutual correlations, underlying geology and other factors which affect abundances. In conclusion, A. torrentium is able to inhabit waters with a large range of physical and chemical parameters of the water without any fundamental influence on population densities. Water properties play an indisputable role as limiting ecological factors at uncommon concentrations, but population densities are probably influenced much more by the types of habitats, habitat features, predation and other ecological factors.

EFFECTS OF RATION SIZE AND TEMPERATURE ON MOULT INCREMENT AND METABOLIC PARAMETERS OF JUVENILE NOBLE CRAYFISH, ASTACUS ASTACUS

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RENAI B.

2007-07-01

Full Text Available A laboratory experiment was carried out to test the combined effects of ration size (1 vs 3% body weight, b.w. and temperature (15 ± 2 vs 22 ± 2 °C on moult increment and metabolic parameters of 80 juvenile noble crayfish (Astacus astacus. The maximum daily consumption (Cmax and respiration rate (R were used to calculate the growth scope (i.e. the difference between maximum daily energy consumption and energy costs at a given temperature. The conversion of R into a food-equivalent unit allowed the comparison with Cmax. Results showed that crayfish obtained the maximum moult increment when fed 3% b.w. while temperature seemed to play a less relevant role on growth rate per moult, affecting only the moulting frequency. Crayfish A. astacus fed ad libitum showed a relative insensitivity to the metabolic parameters (oxygen uptake, R and Cmax within the analysed range of temperatures, possibly as a reflection of this “species” distribution across a broad variety of habitats with different thermal regimes. In the present study, A. astacus displayed characteristics proper of a K-selected species, as slow to moderate growth.

The Effects of Corrosive Chemicals on Corrosion Rate of Steel Reinforcement Bars: I. Swamp Water

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Sulistyoweni Widanarko

2010-10-01

Full Text Available Most of infrastructures using steel concrete to reinforce the strength of concrete. Steel concrete is so vulnerable to chemical compounds that can cause corrosion. It can happen due to the presence of chemical compounds in acid environment in low pH level. These chemical compounds are SO42-, Cl-, NO3-. There are many swamp area in Indonesia. The acid contents and the concentration of ion sulphate, chlorides, and nitrate are higher in the swamp water than in the ground water .The objective of this research was to find out the influence of corrosive chemicals in the swamp water to the steel concrete corrosion rate. There were two treatment used: (1 emerging ST 37 and ST 60 within 60 days in the 'polluted' swamp water, (2 moving the ST 37 up and down periodically in the ' polluted' swamp water. Three variation of 'polluted' swamp water were made by increasing the concentration of corrosive chemical up to 1X, 5X and 10X respectively. The corrosion rate was measured by using an Immersion Method. The result of Immersion test showed that chloride had the greatest influence to corrosion rate of ST 37 and ST 60 and followed by sulphate and Nitrate. Corrosion rate value for ST 37 is 24.29 mpy and for ST 60 is 22.76 mpy. By moving the sample up and down, the corrosion rate of ST 37 increase up to 37.59 mpy, and chloride still having the greatest influence, followed by sulphate and nitrate.

The effect of sensory feedback on crayfish posture and locomotion: II. Neuromechanical simulation of closing the loop.

Science.gov (United States)

Bacqué-Cazenave, Julien; Chung, Bryce; Cofer, David W; Cattaert, Daniel; Edwards, Donald H

2015-03-15

Neuromechanical simulation was used to determine whether proposed thoracic circuit mechanisms for the control of leg elevation and depression in crayfish could account for the responses of an experimental hybrid neuromechanical preparation when the proprioceptive feedback loop was open and closed. The hybrid neuromechanical preparation consisted of a computational model of the fifth crayfish leg driven in real time by the experimentally recorded activity of the levator and depressor (Lev/Dep) nerves of an in vitro preparation of the crayfish thoracic nerve cord. Up and down movements of the model leg evoked by motor nerve activity released and stretched the model coxobasal chordotonal organ (CBCO); variations in the CBCO length were used to drive identical variations in the length of the live CBCO in the in vitro preparation. CBCO afferent responses provided proprioceptive feedback to affect the thoracic motor output. Experiments performed with this hybrid neuromechanical preparation were simulated with a neuromechanical model in which a computational circuit model represented the relevant thoracic circuitry. Model simulations were able to reproduce the hybrid neuromechanical experimental results to show that proposed circuit mechanisms with sensory feedback could account for resistance reflexes displayed in the quiescent state and for reflex reversal and spontaneous Lev/Dep bursting seen in the active state. Copyright © 2015 the American Physiological Society.

Decline of the Maurepas Swamp, Pontchartrain Basin, Louisiana, and Approaches to Restoration

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Gary P. Shaffer

2016-03-01

Full Text Available The Maurepas swamp is the second largest contiguous coastal forest in Louisiana but it is highly degraded due to subsidence, near permanent flooding, nutrient starvation, nutria herbivory, and saltwater intrusion. Observed tree mortality rates at study sites in the Maurepas swamp are very high (up to 100% tree mortality in 11 years and basal area decreased with average salinities of <1 ppt. Habitat classification, vegetation productivity and mortality, and surface elevation changes show a clear trajectory from stagnant, nearly permanently flooded forests with broken canopy to degraded forests with sparse baldcypress and dominated by herbaceous species and open water to open water habitat for most of the Maurepas swamp without introduction of fresh water to combat saltwater intrusion and stimulate productivity and accretion. Healthy forests in the Maurepas are receiving fresh water containing nutrients and sediments from urban areas, high quality river water, or secondarily treated municipal effluent. Currently, two proposed diversions into the swamp are via Hope Canal (57 m3·s−1 and Blind River (142 m3·s−1. These diversions would greatly benefit their immediate area but they are too small to influence the entire Maurepas sub-basin, especially in terms of accretion. A large diversion (>1422 m3·s−1 is needed to deliver the adequate sediments to achieve high accretion rates and stimulate organic soil formation.

Skin disease affecting the conservation of the western swamp tortoise (Pseudemydura umbrina)

Science.gov (United States)

Ladyman, J M; Kuchling, G; Burford, D; Boardman, W; Raidal, S R

1998-11-01

To review the present position of the western swamp tortoise (Pseudemydura umbrina) as an endangered species and significant health issues affecting efforts to save it from extinction. A retrospective analysis of the husbandry, hospital and pathology records of the western swamp tortoise captive breeding program at Perth Zoo. In 1987 a captive breeding project was developed to prevent the extinction of the western swamp tortoise but an outbreak of a necrotising dermatitis in 1989 threatened the survival of the captive bred hatchlings. Less severe outbreaks occurred in 1990 and 1993, with isolated cases in between. Of 283 tortoises that were born in captivity or came into captivity from the wild, 37 (13.1%) were affected, comprising 37% of all males, 26% of all females and 13% of animals of unknown gender. Of the affected animals, 70% were less than 2 years of age and 29% were older. Males were 1.6 times more likely to be infected than females but this difference was not statistically significant (P = 0.27). Culture of the lesions consistently yielded unidentified Pseudomonas sp. Improved husbandry, such as strict maintenance of water quality and temperature conditions similar to that of the animal's natural habitat, and monitoring the health of individual tortoises have successfully controlled skin disease in the captive breeding of the western swamp tortoise.

The fungal flora of the mangrove swamps of Goa

Digital Repository Service at National Institute of Oceanography (India)

Matondkar, S.G.P.; Mahtani, S.; Mavinkurve, S.

Mangrove swamps of Goa (India) showed the presence of fungi belonging to 14 different genera, predominant ones being Monilia, Mucor, Syncephalastrum, Aspergillus and Trichothecium. Most of the isolates were found to be physiologically active...

Food swamps and food deserts in Baltimore City, MD, USA: associations with dietary behaviours among urban adolescent girls.

Science.gov (United States)

Hager, Erin R; Cockerham, Alexandra; O'Reilly, Nicole; Harrington, Donna; Harding, James; Hurley, Kristen M; Black, Maureen M

2017-10-01

To determine whether living in a food swamp (≥4 corner stores within 0·40 km (0·25 miles) of home) or a food desert (generally, no supermarket or access to healthy foods) is associated with consumption of snacks/desserts or fruits/vegetables, and if neighbourhood-level socio-economic status (SES) confounds relationships. Cross-sectional. Assessments included diet (Youth/Adolescent FFQ, skewed dietary variables normalized) and measured height/weight (BMI-for-age percentiles/Z-scores calculated). A geographic information system geocoded home addresses and mapped food deserts/food swamps. Associations examined using multiple linear regression (MLR) models adjusting for age and BMI-for-age Z-score. Baltimore City, MD, USA. Early adolescent girls (6th/7th grade, n 634; mean age 12·1 years; 90·7 % African American; 52·4 % overweight/obese), recruited from twenty-two urban, low-income schools. Girls' consumption of fruit, vegetables and snacks/desserts: 1·2, 1·7 and 3·4 servings/d, respectively. Girls' food environment: 10·4 % food desert only, 19·1 % food swamp only, 16·1 % both food desert/swamp and 54·4 % neither food desert/swamp. Average median neighbourhood-level household income: $US 35 298. In MLR models, girls living in both food deserts/swamps consumed additional servings of snacks/desserts v. girls living in neither (β=0·13, P=0·029; 3·8 v. 3·2 servings/d). Specifically, girls living in food swamps consumed more snacks/desserts than girls who did not (β=0·16, P=0·003; 3·7 v. 3·1 servings/d), with no confounding effect of neighbourhood-level SES. No associations were identified with food deserts or consumption of fruits/vegetables. Early adolescent girls living in food swamps consumed more snacks/desserts than girls not living in food swamps. Dietary interventions should consider the built environment/food access when addressing adolescent dietary behaviours.

The impact of the Suwannee River Sill on the surface hydrology of Okefenokee Swamp, USA

Science.gov (United States)

Yin, Zhi-Yong; Brook, George A.

1992-08-01

Okefenokee Swamp, located in southeastern Georgia and northeastern Florida, is one of the largest freshwater wetland complexes and a National Wildlife Refuge in the United States. A low earthen dam, the Suwannee River Sill, was built on the largest outlet stream of Okefenokee Swamp in the early 1960s. The purpose was to raise the water level and thus reduce fire frequency in this National Wildlife Refuge. In this study, hydrologic conditions in the swamp prior to (1937-1962) and after (1963-1986) sill construction were compared by statistical procedures. An average 9 cm increase in swamp water level at the Suwannee Canal Recreation Area was attributed to the sill. Increased precipitation and decreased evapotranspiration during the study period caused another 5 cm increase in water levels. Seasonal changes in climatic factors were also responsible for seasonal changes in water levels and streamflow in the pre- and post-sill periods. Although the effect of the sill on water level was more significant during dry periods, it is doubtful that the Suwannee River Sill actually prevented occurrence of severe fibres in the post-sill period, which was wetter than the period before sill construction. The sill diverted 2.6% of swamp outflow from the Suwannee River to the St. Mary's River. Diversion of flow was more marked during low flow periods. Therefore, the discharge of the St. Mary's River in the post-sill increased more than the discharge of the Suwannee River and its variability became lower that of the Suwannee River. The relationships between swamp water level, streamflow and precipitation were also changed due to construction of the sill.

Fishes, mussels, crayfishes, and aquatic habitats of the Hoosier-Shawnee ecological assessment area

Science.gov (United States)

M. Burr Brooks; Justin T. Sipiorski; Matthew R. Thomas; Kevin S. Cummings; Christopher A. Taylor

2004-01-01

The Hoosier-Shawnee Ecological Assessment Area, part of the Coastal Plain and Interior Low Plateau physiographic provinces, includes 194 native fish species, 76 native mussel species, and 34 native crayfish species. Five of the subregions (e.g., Mississippi Embayment) that make up the assessment area were recently ranked as either globally or bioregionally outstanding...

Imported Asian swamp eels (Synbranchidae: Monopterus) in North American live food markets: Potential vectors of non-native parasites

Science.gov (United States)

Nico, Leo G.; Sharp, Paul; Collins, Timothy M.

2011-01-01

Since the 1990s, possibly earlier, large numbers of Asian swamp eels (Synbranchidae: Monopterus spp.), some wild-caught, have been imported live from various countries in Asia and sold in ethnic food markets in cities throughout the USA and parts of Canada. Such markets are the likely introduction pathway of some, perhaps most, of the five known wild populations of Asian swamp eels present in the continental United States. This paper presents results of a pilot study intended to gather baseline data on the occurrence and abundance of internal macroparasites infecting swamp eels imported from Asia to North American retail food markets. These data are important in assessing the potential role that imported swamp eels may play as possible vectors of non-native parasites. Examination of the gastrointestinal tracts and associated tissues of 19 adult-sized swamp eels—identified as M. albus "Clade C"—imported from Vietnam and present in a U.S. retail food market revealed that 18 (95%) contained macroparasites. The 394 individual parasites recovered included a mix of nematodes, acanthocephalans, cestodes, digeneans, and pentastomes. The findings raise concern because of the likelihood that some parasites infecting market swamp eels imported from Asia are themselves Asian taxa, some possibly new to North America. The ecological risk is exacerbated because swamp eels sold in food markets are occasionally retained live by customers and a few reportedly released into the wild. For comparative purposes, M. albus "Clade C" swamp eels from a non-native population in Florida (USA) were also examined and most (84%) were found to be infected with internal macroparasites. The current level of analysis does not allow us to confirm whether these are non-native parasites.

[Amphibians and reptiles in the swamps dominated by the palm Raphia taedigera (Arecaceae) in northeastern Costa Rica].

Science.gov (United States)

Bonilla-Murillo, Fabian; Beneyto, Davinia; Sasa, Mahmood

2013-09-01

The herpetofauna that inhabits Caribbean Costa Rica has received considerable attention in the last two decades. This assemblage includes a total of 141 species of reptiles and 95 amphibians mostly distributed in tropical wet and moist lowland forests. While most information available came from primary and secondary forest sites, little is known about the amphibians and reptiles that inhabit more open habitats, such as wetlands and swamps. For instances, swaps dominated by the yolillo palm Raphia taedigera extend through much of the northeastern Caribbean coast of Costa Rica and eastern Nicaragua, but information about the herpetological community that uses such environments remains practically unknown. This situation reflects the little research conducted in such inhospitable environments. Here, we report the results of an intensive survey conducted to assess the herpetological community that inhabit R. taedigera palm-swamps. A total of 14 species of amphibians and 17 of reptiles have been recorded from these swamps. Amphibians and reptiles that inhabit yolillo swamps have wide distributions along much of Middle America and are considered common species throughout their range. In general, yolillo swamps are poor environments for herpetofauna: richness of reptiles and amphibians is almost two times higher in the adjacent forest than in the palm dominated swamps. Furthermore, most species observed in this swamps can be considered habitat generalists that are well adapted to the extreme conditions imposed by the changes in hydroperiods, reduce understory cover, low tree diversity and simple forest architecture of these environments. Despite similarities in the herpetofauna, it is clear that not all forest species use yolillo habitat, a characteristic that is discussed in terms of physical stress driven by the prolonged hydroperiod and reduced leaflitter in the ground, as these features drive habitat structure and herpetofaunal complexity. Our list of species using

Crayfish Self-Administer Amphetamine in a Spatially Contingent Task

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Udita Datta

2018-05-01

Full Text Available Natural reward is an essential element of any organism’s ability to adapt to environmental variation. Its underlying circuits and mechanisms guide the learning process as they help associate an event, or cue, with the perception of an outcome’s value. More generally, natural reward serves as the fundamental generator of all motivated behavior. Addictive plant alkaloids are able to activate this circuitry in taxa ranging from planaria to humans. With modularly organized nervous systems and confirmed vulnerabilities to human drugs of abuse, crayfish have recently emerged as a compelling model for the study of the addiction cycle, including psychostimulant effects, sensitization, withdrawal, reinstatement, and drug reward in conditioned place preference paradigms. Here we extend this work with the demonstration of a spatially contingent, operant drug self-administration paradigm for amphetamine. When the animal enters a quadrant of the arena with a particular textured substrate, a computer-based control system delivers amphetamine through an indwelling fine-bore cannula. Resulting reward strength, dose-response, and the time course of operant conditioning were assessed. Individuals experiencing the drug contingent on their behavior, displayed enhanced rates of operant responses compared to that of their yoked (non-contingent counterparts. Application of amphetamine near the supra-esophageal ganglion elicited stronger and more robust increases in operant responding than did systemic infusions. This work demonstrates automated implementation of a spatially contingent self-administration paradigm in crayfish, which provides a powerful tool to explore comparative perspectives in drug-sensitive reward, the mechanisms of learning underlying the addictive cycle, and phylogenetically conserved vulnerabilities to psychostimulant compounds.

CORRELATION ANALYSIS OF AGRONOMIC CHARACTERS AND GRAIN YIELD OF RICE FOR TIDAL SWAMP AREAS

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Aris Hairmansis

2013-05-01

Full Text Available Development of rice varieties for tidal swamp areas is emphasized on the improvement of rice yield potential in specific environment. However, grain yield is a complex trait and highly dependent on the other agronomic characters; while information related to the relationship between agronomic characters and grain yield in the breeding program particularly for tidal swamp areas is very limited. The objective of this study was to investigate relationship between agronomic characters and grain yield of rice as a basis for selection of high yielding rice varieties for tidal swamp areas. Agronomic characters and grain yield of nine advanced rice breeding lines and two rice varieties were evaluated in a series of experiments in tidal swamp areas, Karang Agung Ulu Village, Banyuasin, South Sumatra, for four cropping seasons in dry season (DS 2005, wet season (WS 2005/2006, DS 2006, and DS 2007. Result from path analysis revealed that the following characters had positive direct effect on grain yield, i.e. number of productive tillers per hill (p = 0.356, number of filled grains per panicle (p = 0.544, and spikelet fertility (p = 0.215. Plant height had negative direct effect (p = -0.332 on grain yield, while maturity, number of spikelets per panicle, and 1000-grain weight showed negligible effect on rice grain yield. Present study suggests that indirect selection of high yielding tidal swamp rice can be done by selecting breeding lines which have many product tive tillers, dense filled grains, and high spikelet fertility.

Sequence Stratigraphic Appraisal: Coastal Swamp Depobelt In The ...

African Journals Online (AJOL)

Mid-Lower Miocene Agbada sedimentary intercalations of “AB” Field in the coastal swamp depobelt, Western Niger-Delta, were evaluated to determine their sequence stratigraphic character. The analysis was based on a combination of data sets including logs of six wells to describe lithic variations of the Agbada Formation ...

Production Efficiency of Swamp Rice Production in Cross River ...

African Journals Online (AJOL)

This study compares profit maximization, output optimization and resource use efficiency in ... of two varieties of swamp rice by farmers in Cross River State of Nigeria. ... The result of the finding also shows that small-scale farmers were more ...

Genetic characterization of Western European noble crayfish populations (Astacus astacus) for advanced conservation management strategies

NARCIS (Netherlands)

Schrimpf, A.; Piscione, M.; Cammaerts, R.; Collas, M.; Herman, D.; Jung, A.; Ottburg, F.; Roessink, I.; Rollin, X.; Schulz, R.; Theissinger, K.

2017-01-01

One central goal of conservation biology is to conserve the genetic diversity of species in order to protect their adaptive potential. The main objective of this study was to identify management units (MUs) for the threatened noble crayfish (Astacus astacus) in Western Europe by utilizing

Reproductive responses to climatic heat induced by management systems in swamp buffaloes

International Nuclear Information System (INIS)

Dollah, M.A.; Ramakrishnan, N.; Nordin, Y.; Abdullah Sani, R.

1990-01-01

Climatic heat is one of the factors influencing the reproductive performance of swamp buffaloes. Any management system that imposes high climatic heat stress tends to reduce reproductive performance. Buffaloes grazing in an open hilly ranch system reached puberty later (at an age of 33 months) and at heavier body weight (365 kg) than animals raised in confinement (26 months and 289 kg). Physiological data (water metabolism and thyroid activity) indicated that grazing animals had to tolerate a higher heat load. High climatic temperatures were found to depress ovarian activity, especially during the dry season. The effect was observed only in cycling buffaloes denied wallow. Buffaloes having access to wallows were able to maintain their heat balance under various levels of heat load by adjusting their water requirements, mobilizing their body water and adjusting their metabolic rate (thyroid activity). It is concluded that stressful climatic temperatures can depress the reproductive performance of young heifers and adult swamp buffaloes, and that climatic heat stress directly depresses ovarian activity in swamp buffaloes. (author). 16 refs, 1 fig., 4 tabs

Increased microsporidian parasitism of the crayfish Orconectes virilis in an experimentally acidified lake. [Thelohania contejeani

Energy Technology Data Exchange (ETDEWEB)

France, R.L.; Graham, L.

1985-10-01

Orconectes virilis has been identified as a host of the microsporidian Thelohania contejeani in four lakes in the Experimental Lakes Area (ELA), northwestern Ontario. Prevalence of parasitism increased from 1.7% in autumn 1979, to 6.5% and 7.7% in autumns 1980 and 1981 concomitant with experimental acidification of Lake 223 to pH 5.1. By comparison, mean infection rates observed within three reference lakes were between 0.3 to 0.6%. Enhanced microsporidosis is believed to have contributed to a reduction in annual crayfish survival rates for the Lake 223 population of 8% in 1979 and 18% in 1980 compared to averages calculated for the non-acidified lakes. Hypotheses to explain the ten-fold increase in Thelohania parasitism in Lake 223 over background levels for the ELA region include a) increased probagative ability due to elevated rate of crayfish cannibalism or low pH-favored parasite life cycle, and b) decreased host resistance when under sublethal stress.

Genetic characteristic of swamp buffalo (Bubalus bubalis) from Pampangan, South Sumatra based on blood protein profile

Science.gov (United States)

Windusari, Yuanita; Hanum, Laila; Wahyudi, Rizki

2017-11-01

Swamp buffalo (Bubalus bubalis) is an endemic species and one of the genetic wealth of South Sumatra with a distribution area in the district of Pampangan (OganIlir and OganOganIlir). Suspected inbreeding causes decreased phenotypic properties. Inbreeding among various swamp buffalo is certainly not only lower the qualities but also genotypes and phenotypes. It is of interest to determine kinship variants swamp buffaloes from Pampangan through the analysis of a blood protein profile. Blood protein profile of four variants swamps buffalo was studied by using five electrophoresis system i.e. pre-albumin (Palb), albumin (Alb), ceruloplasmin (Cp), transferrin (Tf) and transferrin post (Ptf). In this paper, it is obtained that there was no significant differences among the four variants of the buffaloes were used as a sample. Prealbumin has two alleles (Palb1 and Palb2), albumin has three alleles (Alba, AlbB, AlbC), ceruloplasmin has one allele (BPA), post-transferrin has one allele (PTFA) with an allele frequency 1.0000 at any time transferrin has two alleles (TFA and TFB) with the allele frequency of 0.7500 and 1.0000. Characteristics prealbumin (Palb), albumin (Alb), ceruloplasmin (Cp), and post-transferrin (P-tf) is monomorphic, while transferrin is polymorphic average heterozygosity values all loci (H) 0.1286. Based on average heterozygosity, the swamp buffalo (Bubalusbubalis) from Pampangan has low genetic variation and closest genetic relationship.

The exploitation of swamp plants for dewatering liquid sewage sludge

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Jiří Šálek

2006-01-01

Full Text Available The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6–8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

The influence of coarse-scale environmental features on current and predicted future distributions of narrow-range endemic crayfish populations

Science.gov (United States)

Dyer, Joseph J.; Brewer, Shannon K.; Worthington, Thomas A.; Bergey, Elizabeth A.

2013-01-01

1.A major limitation to effective management of narrow-range crayfish populations is the paucity of information on the spatial distribution of crayfish species and a general understanding of the interacting environmental variables that drive current and future potential distributional patterns. 2.Maximum Entropy Species Distribution Modeling Software (MaxEnt) was used to predict the current and future potential distributions of four endemic crayfish species in the Ouachita Mountains. Current distributions were modelled using climate, geology, soils, land use, landform and flow variables thought to be important to lotic crayfish. Potential changes in the distribution were forecast by using models trained on current conditions and projecting onto the landscape predicted under climate-change scenarios. 3.The modelled distribution of the four species closely resembled the perceived distribution of each species but also predicted populations in streams and catchments where they had not previously been collected. Soils, elevation and winter precipitation and temperature most strongly related to current distributions and represented 6587% of the predictive power of the models. Model accuracy was high for all models, and model predictions of new populations were verified through additional field sampling. 4.Current models created using two spatial resolutions (1 and 4.5km2) showed that fine-resolution data more accurately represented current distributions. For three of the four species, the 1-km2 resolution models resulted in more conservative predictions. However, the modelled distributional extent of Orconectes leptogonopodus was similar regardless of data resolution. Field validations indicated 1-km2 resolution models were more accurate than 4.5-km2 resolution models. 5.Future projected (4.5-km2 resolution models) model distributions indicated three of the four endemic species would have truncated ranges with low occurrence probabilities under the low-emission scenario

The hydrological function of upland swamps in eastern Australia: The role of geomorphic condition in regulating water storage and discharge

Science.gov (United States)

Cowley, Kirsten L.; Fryirs, Kirstie A.; Hose, Grant C.

2018-06-01

Temperate Highland Peat Swamps on Sandstone (THPSS) are a type of wetland found in low-order streams on the plateaus of eastern Australia. They are sediment and organic matter accumulation zones, which combined with a climate of high rainfall and low evaporation function as water storage systems. Changes to the geomorphic structure of these systems via incision and channelisation can have profound impacts on their hydrological function. The aim of this study was to develop an understanding of how changes to the geomorphic structure of these systems alter their hydrological function, measured as changes and variability in swamp water table levels and discharge. We monitored the water table levels and discharges of three intact and three channelised THPSS in the Blue Mountains between March 2015 and June 2016. We found that water levels in intact swamps were largely stable over the monitoring period. Water levels rose only in high rainfall events, returned quickly to antecedent levels after rain, and drawdown during dry periods was not significant. In contrast, the water table levels in channelised THPSS were highly variable. Water levels rose quickly after almost all rainfall events and declined significantly during dry periods. Discharge also showed marked differences with the channelised THPSS discharging 13 times more water than intact swamps, even during dry periods. Channelised THPSS also had flashier storm hydrographs than intact swamps. These results have profound implications for the capacity of these swamps to act as water storage reservoirs in the headwaters of catchments and for their ability to maintain base flow to downstream catchments during dry times. Changes to geomorphic structure and hydrological function also have important implications for a range of other swamp functions such as carbon storage, emission and exports, contaminant sorption, downstream water quality and biodiversity, as well as the overall fate of these swamps under a changing

SURVEY OF ECONOMIC TREES IN FRESH WATER SWAMP OF

African Journals Online (AJOL)

1

2011-05-16

May 16, 2011 ... availability because it determines the number of surviving individuals. This is true for all species of .... 2010). CRUTECH, Calabar forest is a pseudo forest having characteristics of rain and swamp forests. ... as reflected in the random and contiguous distribution. (clumped or aggregated population) of the ...

Influence of Soil Type and Drainage on Growth of Swamp Chestnut Oak (Quercus Michauxii Nutt.) Seedlings

Science.gov (United States)

Donald D. Hook

1969-01-01

Swamp chestnut oak (Quercus michauxii Nutt.) seedlings were grown for 2 years in five soil types in drained and undrained pots. First-year height growth was related to soil type and pot drainage, but second-year height growth was related only to soil type. Results suggest that swamp chestnut oak is site-sensitive. But slow growth, a maximum of 2...

Influences of deforestation on radiation and heat balances in tropical peat swamp forest in Thailand

International Nuclear Information System (INIS)

Suzuki, S.; Ishida, T.; Nagano, T.; Matsukawa, S.

1997-01-01

The difference of radiation and heat balances between a natural peat swamp forest and a deforested secondary forest has been investigated in Narathiwat Province, Thailand. Micrometeorological measurements were conducted continuously on observation towers 38 m and 4 m in heights in the primary forest and the secondary forest respectively. Results show that the deforestation of peat swamp forest leads to an increase in the sensible heat flux in the secondary forest. The yearly average ratio of the sensible heat flux to the net radiation was 20.9% in the peat swamp forest, and 33.2% in the secondary forest from Aug. 1995 to Jul. 1996. A ratio more than 40% was observed only in the dry season in the secondary forest. The change in sensible heat flux seemed to be influenced by the change in ground water levels. (author)

Utilization of Organic Fertilizer on Sweet Corn (Zea mays saccharata Sturt Crop at Shallow Swamp Land

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Midranisiah

2017-01-01

Full Text Available Shallow lowland swamp area has significant potential for cultivation of sweet corn crop. This lowland swamp has rich natural resources such as organic fertilizers from chicken dunk, cow dunk, oil palm fresh bunches and legume cover crops (LCC that are not maximally utilized yet by farmers. These organic fertilizers can be utilized to increase the growth and production of sweet corn crop. The research objective was to determine organic fertilizer types that capable to increase the growth and production of sweet corn crop at shallow lowland swamp area. This research had been conducted from January to April 2015 in Pulau Semambu Village, North Indralaya Subdistrict, Ogan Ilir District, South Sumatra Province. The design used in this research was non-factorial Randomized Block Design (RBD with four treatments of organic fertilizer types with six replications for each treatment. The treatments were consisted of organic fertilizers from chicken dunk, cow dunk, oil palm fresh bunches and legume cover crops (LCC. The results showed that treatment of organic fertilizers from chicken dunk could increase the growth and production of sweet corn at shallow lowland swamp area with yield level of 4.37 kg.plot −1.

Report of mortmorilloniticas clay in the Medina swamp (Cerro Largo district)

International Nuclear Information System (INIS)

Gomez Rifas, C.; Heinzen, W.; Theune, C.

1980-01-01

This report describes the prospect ion work for the montmorillonitics clay in the region of Medina swamp in Cerro Largo district. The existence of new deposits was detected by cartography and geological study.

Diversity and Antagonistic Activity of Actinomycete Strains From Myristica Swamp Soils Against Human Pathogens

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Varghese Rlnoy

2014-05-01

Full Text Available Under the present investigation Actinomycetes were isolated from the soils of Myristica swamps of southern Western Ghats and the antagonistic activity against different human bacterial pathogens was evaluated. Results of the present study revealed that Actinomycetes population in the soils of Myristica swamp was spatially and seasonally varied. Actinomycetes load was varied from 24×104 to 71×103, from 129×103 to 40×103 and from 31×104 to 84×103 in post monsoon, monsoon and pre monsoon respectively. A total of 23 Actinomycetes strains belonging to six genera were isolated from swamp soils. Identification of the isolates showed that most of the isolates belonged to the genus Streptomyces (11, followed by Nocardia (6, Micromonospora (3, Pseudonocardia (1, Streptosporangium (1, and Nocardiopsis (1. Antagonistic studies revealed that 91.3% of Actinomycete isolates were active against one or more tested pathogens, of that 56.52% exhibited activity against Gram negative and 86.95% showed activity against Gram positive bacteria. 39.13% isolates were active against all the bacterial pathogens selected and its inhibition zone diameter was also high. 69.5% of Actinomycetes were exhibited antibacterial activity against Listeria followed by Bacillus cereus (65.21%, Staphylococcus (60.86%, Vibrio cholera (52.17%, Salmonella (52.17% and E. coli (39.13%. The results indicate that the Myristica swamp soils of Southern Western Ghats might be a remarkable reserve of Actinomycetes with potential antagonistic activity.

Kennedy Space Center: Swamp Works

Science.gov (United States)

DeFilippo, Anthony Robert

2013-01-01

When I began my internship with the Granular Mechanics and Regolith Operations laboratory (GMRO), also known as Swamp Works, I was given the unique opportunity to shadow many teams working on various projects, and decide what projects I wanted to take part in. Before I go into details of my experiences at Swamp Works, I would like to take a moment to explain what I discovered Swamp Works to be. Swamp Works is a family of hardworking, dedicated, and driven people from various backgrounds and skill sets. These people all work to advance technologies and make science fiction science fact through means of rapid prototyping. They support and encourage failure as an option when learning new things, as long as lesson learned from said failure. In fact, their motto states "Fail, Fast, Forward." What this means is, not if but when one fails he or she must do so quickly and spring forward from the failure so that his or her progress is not delayed. With this acceptance, it provided me the confidence to dive into a multitude of projects working in various fields and with a wide range of skill sets. The first project I joined was Badger. My motivation for taking on this project was the opportunity I would have to obtain valuable experience working with 3D modeling and 3D printing technologies. Badger was a digging apparatus to be used in a highly dusty environment in a material known as Regolith. Regolith is a scientific term for the dirt or top soil found on planetary bodies. Regolith contains a large quantity of sediments less than lOppm and as a result poses a challenge of keeping it out of any cracks and crevices. Furthermore, regolith can create high levels of electrostatic energy, which can prove damaging to sensitive electrical hardware. With these characteristics in mind, I decided to take on the task of designing and manufacturing a dust proof cover for the sensitive electrical hardware. When I began this project, I did not have the slightest idea as to how to use 3D

Utilization of agro-industrial by-products by swamp buffalo

International Nuclear Information System (INIS)

Jelan, Z.A.; Jalaludin, S.; Vijchulata, P.

1987-01-01

A series of studies were conducted to determine the factors affecting the utilization of palm press fibre (PPF) by swamp buffaloes. The nutritive values, fermentation and rumen kinetics, intake and growth responses to a PPF based diet with or without protein and energy supplementation were studied. Palm press fibre was considered a poor quality feed as it is low in crude protein (about 6%) and high in lignin content (about 21%). Dry matter (DM) disappearance from nylon bags at 48 h was low (about 40%) as compared with grass (47%), oaten hay (49%) and lucerne (64%). Sodium hydroxide (8% solution) was most effective as a treating agent as the DM disappearance of PPF from the nylon bags at 48 h was increased by 14%. Dry matter loss from the bags was greater in swamp buffaloes than in cattle. Rumen fluid volume and flow rate were not significantly (P>0.05) increased with fish meal supplementation, but the total dry matter intake (DMI) increased significantly (P<0.05) when 360 g DM/d fish meal was supplemented. Total volatile fatty acid (VFA) concentrations were low in unsupplemented animals and the molar proportions of the VFAs were typical of those seen in the rumen fluid of ruminants fed a fibre based diet. Rumen ammonia-nitrogen was high (40-70 mg/L) in fish meal supplemented animals. When urea treated PPF was supplemented with fish meal and cassava, the animals showed significant increases (P<0.05) in average daily gain and in both total DMI and in the DMI of a basal diet. The study concludes that supplementation with rumen undegradable protein and an energy source are essential to a PPF based diet and that untreated PPF is not a suitable basal diet for swamp buffaloes. (author)

Residu Gula Glikokonjugat pada Lambung Depan Kerbau Rawa (Bubalus bubalis Kalimantan Selatan (SUGAR RESIDU OF GLYCOCONJUGATES IN FORESTOMACH OF SOUTH KALIMANTAN SWAMP BUFFALO (BUBALUS BUBALIS

Directory of Open Access Journals (Sweden)

Anni Nurliani

2014-08-01

Full Text Available The ability of swamp buffaloes to adapt with swamp environment was suggested to be supported bytheir digestive system efficiency. The research was done to obtain scientific explanation about digestiveefficiency of swamp buffalo by identification on kinds and distribution of glycoconjugates in swamp buffaloforestomach. Six male swamp buffaloes aged more than 2.5 year old and had body weight between 300-400kg were used in this study. Samples were obtained from Regency of Banjar slaughter house, SouthKalimantan. Every parts of the forestomach included rumen, reticulum, and omasum was taken andprocessed for microscopic observation with hematoxyline eosin (HE and alcian blue-periodic acid schiff(AB-PAS stainings. Sugar residues of glycoconjugates were localized with lectin histochemistry wheatgerm agglutinin (WGA, ulex europaeus agglutinin (UEA, ricinus communis agglutinin (RCA, concanavalinagglutinin (Con A, and soybean agglutinin (SBA. Every part of swamp buffalo forestomach had kinds ofspecific glycoconjugates with special distribution pattern which were different with other ruminant, andwere suitable for their functions in that part. The existence of D mannose/D glucose glycoconjugates thatwas dominant in forestomach estimated that had important role in supporting fermentative digestionfunction in swamp buffalo, through its function as receptor bacteria attachment. This is suggested as aspecial characteristic in digestive system of swamp buffalo which causes high digestive efficiency inswamp buffalo.

Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia.

Science.gov (United States)

Chen, Guang C; Ulumuddin, Yaya I; Pramudji, Sastro; Chen, Shun Y; Chen, Bin; Ye, Yong; Ou, Dan Y; Ma, Zhi Y; Huang, Hao; Wang, Jing K

2014-07-15

The soil to atmosphere fluxes of greenhouse gases N2O, CH4 and CO2 and their relationships with soil characteristics were investigated in three tropical oceanic mangrove swamps (Teremaal, Likupang and Kema) in North Sulawesi, Indonesia. Mangrove soils in North Sulawesi were rich in organic carbon and nitrogen, but the greenhouse gas fluxes were low in these mangroves. The fluxes ranged -6.05-13.14 μmol m(-2)h(-1), -0.35-0.61 μmol m(-2)h(-1) and -1.34-3.88 mmol m(-2)h(-1) for N2O, CH4 and CO2, respectively. The differences in both N2O and CH4 fluxes among different mangrove swamps and among tidal positions in each mangrove swamp were insignificant. CO2 flux was influenced only by mangrove swamps and the value was higher in Kema mangrove. None of the measured soil parameters could explain the variation of CH4 fluxes among the sampling plots. N2O flux was negatively related to porewater salinity, while CO2 flux was negatively correlated with water content and organic carbon. This study suggested that the low gas emissions due to slow metabolisms would lead to the accumulations of organic matters in North Sulawesi mangrove swamps. Copyright © 2014 Elsevier B.V. All rights reserved.

Study, using stable isotopes, of flow distribution, surface-groundwater relations and evapotranspiration in the Okavango Swamp, Botswana

International Nuclear Information System (INIS)

Dincer, T.; Hutton, L.G.; Kupee, B.B.J.

1979-01-01

Stable isotope data collected in the Okavango Delta have confirmed that the central distributary system is more active at present than the peripheral systems. The data also show that there is no groundwater outflow at the western and southern margins of the delta. A salinity-isotope model of the deltaic swamp has been developed to study the relation between the salinity and isotopic composition of the swamp waters. An attempt has been made to separate the atmospheric losses from the swamp into its evapotranspiration components. The results indicate that in winter, when high water levels prevail, these losses are almost entirely due to evaporation whilst in summer, when the water levels are low, evaporation and transpiration contribute almost equally to the total atmospheric losses. (author)

Hobbseus yalobushensis, a crayfish of intermittent streams: Biotic and habitat associations, life history characteristics, and new localities

Science.gov (United States)

Susan B. Adams; Blake A. Davis; Darren A. Miller

2018-01-01

Hobbseus yalobushensis, the Yalobusha rivulet crayfish, is a species of conservation concern because it is known from only six localities in parts of three central Mississippi counties. No studies have focused on the species since its description in 1989. Our objectives were to: (1) identify additional H. yalobushensis...

The Effects of Corrosive Chemicals on Corrosion Rate of Steel Reinforcement Bars: II. Swamp Sludges

Directory of Open Access Journals (Sweden)

Henki Ashadi

2010-10-01

Full Text Available A polluted environment will influence the building age. The objective of this research was to find out the influence of corrosive chemicals within the sludge swamp area with the corrosion rate of steel concrete. Corrosion in steel concrete usually occur in acid area which contain of SO42-, Cl- and NO3-. The research treatment used by emerging ST 37 andST 60 within 60 days in 'polluted' sludge swamp area. Three variation of 'polluted' swamp sludge were made by increasing the concentration a corrosive unsure up to 1X, 5X and 10X. The corrosion rate measured by using an Immersion Method. The result of Immersion test showed that sulphate had a greatest influence to corrosion rate of ST 37 and ST 60 and followed by chloride and nitrate. Corrosion rate value for ST 37 was 17.58 mpy and for ST 60 was 12.47 mpy.

Invasion of an occupied niche by the crayfish Orconectes rusticus: potential importance of growth and mortality.

Science.gov (United States)

Hill, Anna M; Sinars, Damon M; Lodge, David M

1993-06-01

We are exploring mechanisms of an invasion that contradicts the oft-cited generalization that species invade vacant niches. In northern Wisconsin lakes, the introduced crayfish Orconectes rusticus is replacing two ecologically similar resident congeners, O. virilis and O. propinquus. In laboratory experiments, we compared growth and mortality of individually maintained crayfish offered one of five ad libitum diets: invertebrates, macrophytes, dentritus, periphyton or all items combined. Mortality was highest for O. virilis and lowest for O. rusticus. Macrophyte diets yielded the highest mortality. All three species grew best on invertebrate and combination diets but grew little or not at all on diets of periphyton, detritus or macrophytes. O. rusticus and O. virilis grew more than O. propinquus. O. rusticus grew more quickly and/or was better able to survive overall than its congeners. Therefore, O. rusticus would probably have advantages over O. virilis and O. propinquus in competitive interactions, reproductive success and avoiding size-selective fish predation. Subtle interspecific differences may interact strongly with other ecological factors and contribute to the displacement of resident species from a well-occupied niche.

Biomagnification of some heavy and essential metals in sediments, fishes and crayfish from Ondo State coastal region, Nigeria

International Nuclear Information System (INIS)

Asaolu, S.S.; Olaofe, O.

2005-01-01

The bio magnifications levels of some essential (Fe, Zn, Cu) and toxic metals (Pb, Ni, Cd, Cr, Co, Mn) were determined in sediments, three kinds of fish (Oreochromis niloticus, Synodonthis sp., and Clarias gariepinus) and crayfish from the Ondo State coastal region. The metal bio magnification in the fish and crayfish was several times greater than in water, while that in the sediments was several thousand-folds greater than in both the organisms and water. Among the metals examined in water, Fe was the most abundant with average values of 146.7 and 74.3 mg/1, respectively, for wet and dry seasons, while Co was the least with average values of 2.4 and 1.6 mg/1. In the sediments, concentrations of Pb, Ni, Fe, Cr, Co and Mn in the wet season were relatively higher than those obtained for the dry season. Fe with an average of 50.9 mg/kg in C, gariepinus was the most abundant metal in the fish samples, while Cu with an average value of 0.3 mg/kg in O. niloticus was the least. The metal bio magnification for most of the metals for both seasons was found to vary widely from one location to the other. This was confirmed by the coefficient of variation that ranged from 31% to 144% and 29% to 130% in the wet and dry seasons, respectively. The present study has shown that fish, crayfish and sediments can be used to monitor the pollution level of metals in the Nigerian coastal water. (author)

Glutamatergic postsynaptic block by Pamphobeteus spider venoms in crayfish.

Science.gov (United States)

Araque, A; Ferreira, W; Lucas, S; Buño, W

1992-01-31

The effects of toxins from venom glands of two south american spiders (Pamphobeteus platyomma and P. soracabae) on glutamatergic excitatory synaptic transmission were studied in the neuromuscular junction of the opener muscle of crayfish. The toxins selectively and reversibly blocked both excitatory postsynaptic currents and potentials in a dose-dependent manner. They also reversibly abolished glutamate-induced postsynaptic membrane depolarization. They had no effect on resting postsynaptic membrane conductance nor on postsynaptic voltage-gated currents. The synaptic facilitation and the frequency of miniature postsynaptic potentials were unaffected by the toxins, indicating that presynaptic events were not modified. Picrotoxin, a selective antagonist of the gamma-aminobutyric acid (GABA)A receptor, did not modify toxin effects. We conclude that both toxins specifically block the postsynaptic glutamate receptor-channel complex.

Concentrations of elements in fish fillets, fish muscle plugs, and crayfish from the 2007 Missouri Department of Conservation General Contaminant Monitoring Program

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

2009-01-01

This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillets of channel catfish (Ictalurus punctatus), bass (Micropterus salmoides, Micropterus dolomieu, Morone chrysops), walleye (Sander vitreus), common carp (Cyprinus carpio), lake sturgeon (Acipenser fulvescens), northern hog sucker (Hypentelium nigricans), and rainbow trout (Oncorhynchus mykiss) were collected from 21 sites as part of the Department's Fish Contaminant Monitoring Program. Long-pincered crayfish (Orconectes longidigitus) were collected from one site to assess trophic transfer of metals to fish. Fish muscle plugs were collected from smallmouth bass (Micropterus dolomieu) at two different locations from one site.

Concentrations of elements in fish fillets, fish muscle plugs, and crayfish from the 2011 Missouri Department of Conservation general contaminant monitoring program

Science.gov (United States)

May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

2013-01-01

This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in fish fillets, fish muscle plugs, and crayfish. Fillet samples of yellow bullhead (Ameiurus natalis), golden redhorse (Moxostoma erythrurum), longear sunfish (Lepomis megalotis), and channel catfish (Ictalurus punctatus) were collected from six sites as part of the Missouri Department of Conservation’s Fish Contaminant Monitoring Program. Fish dorsal muscle plugs were collected from largemouth bass (Micropterus salmoides) at eight of the sites, and crayfish from two sites. Following preparation and analysis of the samples, highlights of the data were as follows: cadmium and lead residues were most elevated in crayfish tissue samples from the Big River at Cherokee Landing, with 1 to 8 micrograms per gram dry weight and 22 to 45 micrograms per gram dry weight, respectively. Some dorsal muscle plugs from largemouth bass collected from Clearwater Lake, Lake St. Louis, Noblett Lake, Hazel Creek Lake, and Harrison County Lake contained mercury residues (1.7 to 4.7 micrograms per gram dry weight) that exceeded the U.S. Environmental Protection Agency Water Quality Criterion of 1.5 micrograms per gram dry weight of fish tissue (equivalent to 0.30 micrograms per gram wet weight).

Net ecosystem CO2 exchange of a primary tropical peat swamp forest in Sarawak, Malaysia

Science.gov (United States)

Tang Che Ing, A.; Stoy, P. C.; Melling, L.

2014-12-01

Tropical peat swamp forests are widely recognized as one of the world's most efficient ecosystems for the sequestration and storage of carbon through both their aboveground biomass and underlying thick deposits of peat. As the peat characteristics exhibit high spatial and temporal variability as well as the structural and functional complexity of forests, tropical peat ecosystems can act naturally as both carbon sinks and sources over their life cycles. Nonetheless, few reports of studies on the ecosystem-scale CO2 exchange of tropical peat swamp forests are available to-date and their present roles in the global carbon cycle remain uncertain. To quantify CO2 exchange and unravel the prevailing factors and potential underlying mechanism regulating net CO2 fluxes, an eddy covariance tower was erected in a tropical peat swamp forest in Sarawak, Malaysia. We observed that the diurnal and seasonal patterns of net ecosystem CO2 exchange (NEE) and its components (gross primary productivity (GPP) and ecosystem respiration (RE)) varied between seasons and years. Rates of NEE declined in the wet season relative to the dry season. Conversely, both the gross primary productivity (GPP) and ecosystem respiration (RE) were found to be higher during the wet season than the dry season, in which GPP was strongly negatively correlated with NEE. The average annual NEE was 385 ± 74 g C m-2 yr-1, indicating the primary peat swamp forest functioned as net source of CO2 to the atmosphere over the observation period.

Isolation of vibrio spp. In oysters (crassostrea rhizophorea) caught in the ‘de la virgen’ swamp

OpenAIRE

López Gutiérrez, Lercy; Autor; Manjarrez Pava, Ganiveth; Autor; Herrera Rodríguez, Lilibeth; Autor; Montes Payares, Ana Elena; Autor; Olascuaga Ruíz, Yuranis Paola; Autor; Ortega Quiroz, Rolando José; Autor

2015-01-01

Objective:  To establish contamination by Vibrio in oysters (Crassostrea rhizophorae) caught in De La Virgen Swamp, in order to alert entities in charge or protecting consumer health in Cartagena city. Methods: Between February and April 2006, 67 oysters from 5 strategic sites along De La Virgen Swamp, were analyzed. Insulation and identification of Vibrio was performed through a culture and biochemical tests.Results.  Predominant species were V. alginolyticus (23%),V fluvialis  (20%),V. para...

Mapping swamp timothy (Cripsis schenoides) seed productivity using spectral values and vegetation indices in managed wetlands

Energy Technology Data Exchange (ETDEWEB)

Rahilly, P.J.A.; Li, D.; Guo, Q.; Zhu, J.; Ortega, R.; Quinn, N.W.T.; Harmon, T.C.

2010-01-15

This work examines the potential to predict the seed productivity of a key wetland plant species using spectral reflectance values and spectral vegetation indices. Specifically, the seed productivity of swamp timothy (Cripsis schenoides) was investigated in two wetland ponds, managed for waterfowl habitat, in California's San Joaquin Valley. Spectral reflectance values were obtained and associated spectral vegetation indices (SVI) calculated from two sets of high resolution aerial images (May 11, 2006 and June 9, 2006) and were compared to the collected vegetation data. Vegetation data were collected and analyzed from 156 plots for total aboveground biomass, total aboveground swamp timothy biomass, and total swamp timothy seed biomass. The SVI investigated included the Simple Ratio (SR), Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Transformed Soil Adjusted Vegetation Index (TSAVI), Modified Soil Adjusted Vegetation Index (MSAVI), and Global Environment Monitoring Index (GEMI). We evaluated the correlation of the various SVI with in situ vegetation measurements for linear, quadratic, exponential and power functions. In all cases, the June image provided better predictive capacity relative to May, a result that underscores the importance of timing imagery to coincide with more favorable vegetation maturity. The north pond with the June image using SR and the exponential function (R{sup 2}=0.603) proved to be the best predictor of swamp timothy seed productivity. The June image for the south pond was less predictive, with TSAVI and the exponential function providing the best correlation (R{sup 2}=0.448). This result was attributed to insufficient vegetal cover in the south pond (or a higher percentage of bare soil) due to poor drainage conditions which resulted in a delay in swamp timothy germination. The results of this work suggest that spectral reflectance can be used to estimate seed productivity in managed seasonal

ANNUAL ACTIVITY OF THE NOBLE CRAYFISH (ASTACUS ASTACUS) IN THE ORLJAVA RIVER (CROATIA)

OpenAIRE

FALLER M.; MAGUIRE I.; KLOBUČAR G.

2006-01-01

We studied the annual activity of the noble crayfish (Astacus astacus) at three sites along the Orljava River, in the continental part of Croatia, between August 2003 and September 2004. Each site represented the typical characteristics of the upper, middle and lower section of the river (5, 24 and 37 km from the spring, respectively). The biggest population size was recorded on the most upstream site, with greatest structural variability of bottom, high biotic index, and the lowest mean wate...

Aluminum and iron contents in phosphate treated swamp rice farm ...

African Journals Online (AJOL)

In 2006 aluminum and iron contents were determined in phosphate treated swamp rice farm of Mbiabet, Akwa Ibom State. The objectives were to determine the aluminum and iron contents, the effect of drying, phosphate and lime application in an acid sulphate soil grown to rice in Nigeria. The soil samples used were ...

Species Turnover across Different Life Stages from Seedlings to Canopy Trees in Swamp Forests of Central Brazil

Directory of Open Access Journals (Sweden)

Clarissa G. Fontes

2015-01-01

Full Text Available Processes driving the assembly of swamp forest communities have been poorly explored. We analyzed natural regeneration and adult tree communities data of a swamp gallery forest in Central Brazil to discuss the role of ecological filters in shaping plant species turnover in a successional gradient. Species data of 120 plots were used to assess species turnover between natural regeneration and adult tree communities. Our analyses were based on 4995 individuals belonging to 72 species. Community patterns were discerned using ordination analyses. A clear floristic turnover among plant life stages was distinguished. Regeneration community of swamp forests was richer in species composition than the adult community. Tree species commonly found in nonflooded gallery forests were present in the regeneration plots but not in the adult community. Differences in the floristic composition of these two strata suggest that not all species in the seedling stage can stand permanent flooding conditions and only a few tolerant species survive to become adult trees. We propose that natural disturbances play an important role by altering limiting resources, allowing seeds of nonflooded forest species to germinate. This paper elucidates the turnover between plant life stages in swamp forests and suggests mechanisms that may shape these communities.

Interdisciplinarity to reconstruct historical introductions: solving the status of cryptogenic crayfish.

Science.gov (United States)

Clavero, Miguel; Nores, Carlos; Kubersky-Piredda, Susanne; Centeno-Cuadros, Alejandro

2016-11-01

Anciently introduced species can be confounded with native species because introduction pre-dates the first species inventories or because of the loss of the collective memory of the introductions. The term 'cryptogenic species' denotes species of unknown or unclear status (native versus non-native) in a given territory, and disciplinary approaches are often insufficient for solving their true status. Here, we follow an integrative, multidisciplinary approach to solve the status of a cryptogenic species, proposing that building on evidence from multiple disciplines can produce robust and clarifying insights. We undertook an exhaustive review of information on a putatively native crayfish (Austropotamobius italicus) in Spain. The reviewed information included taxonomy, genetics and phylogeography, history, archaeology, linguistics, biogeography, ecology, symbiotic organisms and even gastronomy and pharmacy. The knowledge produced by different scientific disciplines converges to indicate that A. italicus is a non-native species in Spain. Historical documents even identify the first introduction event: crayfish were shipped from Italy to Spain in 1588 as a diplomatic gift from Francesco I de' Medici to King Philip II of Spain. Previous discussions on the status of A. italicus focussed on inconclusive and often confusing genetic results and excluded the rich and clarifying evidence available from other approaches and disciplines. Interdisciplinarity is an often-invoked but rarely implemented practice in an academic environment that increasingly promotes narrow-focussed specialization. Our review shows that the integration of disciplines can surpass disciplinary approaches in solving scientific controversies. Our results have straightforward implications for strategies to conserve biological diversity in Spain and Europe, urging a debate on the appropriateness of devoting conservation efforts to non-native species. © 2015 Cambridge Philosophical Society.

Neuromodulation of reciprocal glutamatergic inhibition between antagonistic motoneurons by 5-hydroxytryptamine (5-HT) in crayfish walking system.

Science.gov (United States)

Pearlstein, E; Clarac, F; Cattaert, D

1998-01-23

In an in vitro preparation of the crayfish thoracic locomotor system, paired intracellular recordings were performed from antagonistic depressor (Dep) and levator (Lev) motoneurons (MNs) that control the second joint of walking legs. Connections between these two groups of MNs consist mainly of inhibitory connections and weak electrotonic synapses. Injection of depolarizing current into a Lev MN results in a hyperpolarization in a Dep MN, and vice versa. This reciprocal glutamatergic inhibition, is not changed in the presence of the sodium channel blocker tetrodotoxin (TTX) and therefore is likely supported by a direct connection between MNs. By contrast, reciprocal inhibition is largely reduced in the presence of 5-hydroxytryptamine (5-HT; 10 microM). Direct micro-application of glutamate pressure-ejected close to an intracellularly recorded MN, evoked an inhibitory response in that MN, accompanied by a decrease of input resistance. These two effects were dramatically reduced in the presence of 5-HT. Thus 5-HT could be involved in mechanisms of dynamic reconfigurations of the neural network controlling leg movements in crayfish.

Project conservation and handling for the multiple uses and the development of the swamps of Colombia

International Nuclear Information System (INIS)

Sanchez Paez, Heliodoro

1998-01-01

In Colombia the swamps are distributed in the Atlantic and Pacific coasts; they are located in areas with conditions of pluvial precipitation that varies from annual 200 mm in the Guajira department; nine species of mangroves have registered for Colombia, which are related following a zonation starting from the tide line, still when this pattern not always stays and it depends on the influence of diverse factors and local conditions. The project conservation and handling for the multiple use and the development of the swamps of Colombia, had as objectives; to watch and to control the parameters of salinity, level of water and flow to laminate and of strengthening the generation of alternative productive social and environmentally appropriate for the sustainable use, guaranteeing their conservation and preservation of the swamps. The project was developed in two phases, one of diagnostic and planning and the other of dynamics of growth, phenology and natural regeneration

Swamp tours in Louisiana post Hurricane Katrina and Hurricane Rita

Science.gov (United States)

Dawn J. Schaffer; Craig A. Miller

2007-01-01

Hurricanes Katrina and Rita made landfall in southern Louisiana during August and September 2005. Prior to these storms, swamp tours were a growing sector of nature-based tourism that entertained visitors while teaching about local flora, fauna, and culture. This study determined post-hurricane operating status of tours, damage sustained, and repairs made. Differences...

Biocontrol for Rhizoctonia Stem Rot Disease by Using Combination of Specific Endophyte in Paddy Tidal Swamp

OpenAIRE

Budi, Ismed Setya; Mariana, Mariana

2013-01-01

The use of combination of specific endophytic in tidal swamps to control stem root disease as biological control agents has not been done. It is expected that this combination is able to continuously protect plants from pathogen interference. The research was carried out in type C tidal swamp in Banjar regency of South Kalimantan, from March to November 2011, temperature 29-32oC, and pH 4.0-5.5. The method used was Split Plot design. Biocontrol preparation for both types of endophytic was ap...

Operational restoration of the Pen Branch bottomland hardwood and swamp wetlands - the research setting

International Nuclear Information System (INIS)

Nelson, E.A.

2000-01-01

The Savannah River Swamp is a 3020 Ha forested wetland on the floodplain of the Savannah River and is located on the Department of Energy's Savannah River Site (SRS) near Aiken, SC. Historically the swamp consisted of approximately 50 percent bald cypress-water tupelo stands, 40 percent mixed bottomland hardwood stands, and 10 percent shrub, marsh, and open water. Creek corridors were typical of Southeastern bottomland hardwood forests. The hydrology was controlled by flooding of the Savannah River and by flow from four creeks that drain into the swamp prior to flow into the Savannah River. Upstream dams have caused some alteration of the water levels and timing of flooding within the floodplain. Major impacts to the swamp hydrology occurred with the completion of the production reactors and one coal-fired powerhouse at the SRS in the early 1950's. Water was pumped from the Savannah River, through secondary heat exchangers of the reactors, and discharged into three of the tributary streams that flow into the swamp. Flow in one of the tributaries, Pen Branch, was typically 0.3 m3 s-1 (10-20) cfs prior to reactor pumping and 11.0 m3 s-1 (400 cfs) during pumping. This continued from 1954 to 1988 at various levels. The sustained increases in water volume resulted in overflow of the original stream banks and the creation of additional floodplains. Accompanying this was considerable erosion of the original stream corridor and deposition of a deep silt layer on the newly formed delta. Heated water was discharged directly into Pen Branch and water temperature in the stream often exceeded 65 degrees C. The nearly continuous flooding of the swamp, the thermal load of the water, and the heavy silting resulted in complete mortality of the original vegetation in large areas of the floodplain. In the years since pumping was reduced, early succession has begun in some affected areas. Most of this has been herbs, grasses, and shrubs. Areas that have seedlings are generally willow

TEMPORAL VEGETATION DYNAMICS IN PEAT SWAMP AREA USING MODIS TIME-SERIES IMAGERY: A MONITORING APPROACH OF HIGH-SENSITIVE ECOSYSTEM IN REGIONAL SCALE

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Yudi Setiawan

2016-10-01

Full Text Available Peat swamp area is an essential ecosystem due to high vulnerability of functions and services. As the change of forest cover in peat swamp area has increased considerably, many studies on peat swamp have focused on forest conversion or forest degradation. Meanwhile, in the context of changes in the forestlands are the sum of several processes such as deforestation, reforestation/afforestation, regeneration of previously deforested areas, and the changing spatial location of the forest boundary. Remote sensing technology seems to be a powerful tool to provide information required following that concerns. A comparison imagery taken at the different dates over the same locations for assessing those changes tends to be limited by the vegetation phenology and land-management practices. Consequently, the simultaneous analysis seems to be a way to deal with the issues above, as a means for better understanding of the dynamics changes in peat swamp area. In this study, we examined the feasibility of using MODIS images during the last 14 years for detecting and monitoring the changes in peat swamp area. We identified several significant patterns that have been assigned as the specific peat swamp ecosystem. The results indicate that a different type of ecosystem and its response to the environmental changes can be portrayed well by the significant patterns. In understanding the complex situations of each pattern, several vegetation dynamics patterns were characterized by physical land characteristics, such as peat depth, land use, concessions and others. Characterizing the pathways of dynamics change in peat swamp area will allow further identification for the range of proximate and underlying factors of the forest cover change that can help to develop useful policy interventions in peatland management.

Approaches for the environmental evaluation of two swamp complexes of the Momposina depression

International Nuclear Information System (INIS)

Caballero, Humberto; Durango, Consuelo

1998-01-01

The swamp complexes of the Momposina depression in the lower Magdalena River have been submitted to irrational exploitation, transformation and contamination mainly since the beginning of the century, process that has be en getting worse in the last decade. The most evident manifestation of the environmental deterioration is expressed by the drastic reduction of fishing, with important socio-economic effects to the population that lives from this source. The most notorious causes of the actual state of the ecosystem were detected, and some preliminary considerations for its management are presented. However, due to the modifications that the complexes have suffered (closure of the natural sewer, construction of jarillones, modifications of the internal water flows and sediments, over exploitation, of fish and herpetofauna), the deterioration of the limnologic conditions is moderated, which allows to begin recuperation plans. The major impacts were observed in the fauna of birds and reptiles associated to the swamps; the decrease of the ictics populations seems to be related to the strong impact generated by the fishing action used and the interruption of the natural cycles of fish. The possibility of rebuilding the communication swamp-river should be studied with care because it seems the system has arrived to new conditions. The re-opening of the sewers could mean a new unbalanced condition represented mainly by the contamination coming from the Magdalena River

Distribution and establishment of the alien Australian redclaw crayfish, Cherax quadricarinatus, in South Africa and Swaziland

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Ana L. Nunes

2017-04-01

Full Text Available Background The Australian redclaw crayfish (Cherax quadricarinatus, von Martens, is native to Australasia, but has been widely translocated around the world due to aquaculture and aquarium trade. Mostly as a result of escape from aquaculture facilities, this species has established extralimital populations in Australia and alien populations in Europe, Asia, Central America and Africa. In South Africa, C. quadricarinatus was first sampled from the wild in 2002 in the Komati River, following its escape from an aquaculture facility in Swaziland, but data on the current status of its populations are not available. Methods To establish a better understanding of its distribution, rate of spread and population status, we surveyed a total of 46 sites in various river systems in South Africa and Swaziland. Surveys were performed between September 2015 and August 2016 and involved visual observations and the use of collapsible crayfish traps. Results Cherax quadricarinatus is now present in the Komati, Lomati, Mbuluzi, Mlawula and Usutu rivers, and it was also detected in several off-channel irrigation impoundments. Where present, it was generally abundant, with populations having multiple size cohorts and containing ovigerous females. In the Komati River, it has spread more than 112 km downstream of the initial introduction point and 33 km upstream of a tributary, resulting in a mean spread rate of 8 km year−1 downstream and 4.7 km year−1 upstream. In Swaziland, estimated downstream spread rate might reach 14.6 km year−1. Individuals were generally larger and heavier closer to the introduction site, which might be linked to juvenile dispersal. Discussion These findings demonstrate that C. quadricarinatus is established in South Africa and Swaziland and that the species has spread, not only within the river where it was first introduced, but also between rivers. Considering the strong impacts that alien crayfish usually have on invaded ecosystems

Greenhouse gas efflux from an impacted Malaysian tropical peat swamp (Invited)

Science.gov (United States)

Waldron, S.; Vihermaa, L. E.; Evers, S.; Garnett, M.; Newton, J.; Padfield, R.

2013-12-01

Tropical peatlands constitute ~11% of global peatland area and ~12% of the global peat C pool. Malaysia alone contains 10% of tropical peats. Due to rising global demands for food and biofuels, SE-Asia peat swamp forest ecosystems are threatened by increasing amounts of drainage, fire and conversion to plantation. These processes can change the GHG emissions and thus net ecosystem C balance. However, in comparison to temperate and boreal peatlands, there is a lack of data on terrestrial-aquatic-atmospheric carbon transfer from tropical peatlands, both those that are little disturbed and those facing anthropogenic pressures. Lateral transport of soil-respired carbon, and fluvial respiration or UV-oxidation of terrestrial DOC primes atmospheric carbon dioxide efflux. We now know that DOC lost from disturbed tropical peat swamp forests can be centuries to millennia old and originates deep within the peat column - this carbon may fuel efflux of old carbon dioxide and so anthropogenic land-use change renders the older, slower carbon cycles shorter and faster. Currently we have no knowledge of how significant ';older-slower' terrestrial-aquatic-atmospheric cycles are in disturbed tropical peatlands. Further, in some areas for commercial reasons, or by conservation bodies trying to minimise peat habitat loss, logged peats have been left to regenerate. Consequently, unpicking the legacy of multiple land uses on magnitude, age and source of GHG emissions is challenging but required to support land management decisions and projections of response to a changing climate. Here, we present the results of our first field campaign in July 2013 to the Raja Musa and Sungai Karang Peat Swamp Forest Reserves in North Selangor, Malaysia. This is one of Malaysia's largest oceanic peat swamps, and has been selectively logged and drained for 80 years, but is now subject to a 30 year logging ban to aid forest regeneration and build up wood stocks. From sites subject to different land use

Mapping Upper Amazon Palm Swamps with Spaceborne L-band Synthetic Aperture Radar

Science.gov (United States)

Pinto, N.; McDonald, K. C.; Podest, E.; Schroeder, R.; Zimmermann, R.; Horna, V.

2010-12-01

Palm swamp ecosystems are widespread in the Amazon basin, forming where seasonal flooding is moderate and surface inundation persists. Recent studies suggest that palm swamps have a disproportional role on tropical biogeochemistry: the combination of persistently saturated soils, warm temperatures, and low oxygen soils can support significant land-atmosphere methane flux. Potential impacts of climate change on these ecosystems include changes in temperature and precipitation regimes that influence primary productivity and flood extent significantly, potentially reversing net land-atmosphere carbon exchanges regionally. Data acquired from Earth-orbiting satellites provides the opportunity to characterize vegetation structure and monitor surface inundation independently of cloud cover. Building on efforts under our NASA MEaSUREs project for assembly of a global-scale Earth System Data Record (ESDR) of inundated wetlands, we develop and evaluate a systematic approach to map the distribution and composition of palm swamps in the upper Amazon using data sets from JAXA’s Advanced Land Observing Satellite (ALOS) Phased Array L-Band SAR (PALSAR). Our input dataset consists of HH backscatter images acquired in 2007 and 2009. Ground measurements for training were obtained from a study site near Loreto, Peru (4.43S 75.34W) containing the palm species Mauritia flexuosa. The ALOS PALSAR images are first averaged temporally and spatially. We then develop ancillary data layers of flood extent, distance from open water, and SAR image texture. The PALSAR data and derived ancillary layers are combined with MODIS Vegetation Indices and SRTM elevation and input in a classification framework. Since palm swamps are found in persistently flooded areas, we evaluate the potential of identifying and mapping these ecosystems using multi-temporal SAR-based flood extent maps. We conclude by comparing the performance between a decision-tree supervised vs. unsupervised approach and by

Mitochondrial DNA provides evidence of a double origin for the stone crayfish Austropotamobius torrentium in the Elbe basin

Czech Academy of Sciences Publication Activity Database

Petrusek, A.; Pešek, P.; Leština, Dan; Martin, P.; Fischer, D.; Kozák, P.; Vlach, P.

2017-01-01

Roč. 62, JAN 01 (2017), s. 77-83 ISSN 0075-9511 Institutional support: RVO:60077344 Keywords : stone crayfish * Austropotamobius torrentium * Elbe basin Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 1.427, year: 2016 https://www.sciencedirect.com/science/article/pii/S0075951116300901

Beautiful, but also potentially invasive

Directory of Open Access Journals (Sweden)

Lipták Boris

2015-03-01

Full Text Available Introduction of non-indigenous exotic species to new areas, where they may establish viable populations and become invasive, is a considerable problem in the protection of nature worldwide, as these species may alter the indigenous species population structure and potentially even decrease the biodiversity. The European fauna underwent through major negative changes on the continent and nowadays, it experiences another new treat, represented by the expanding aquarium pet trade, and with it, associated species (and disease introductions. Exotic freshwater crustaceans are one of the taxa widely incorporated in the business, counting a remarkable number of species. Recent records of the exotic marbled crayfish or Marmorkrebs (Procambarus fallax f. virginalis in German in open ecosystems in Slovakia pointed to human-mediated introductions associated with aquarium pet trade in the country. In this regard, a study of the aquarium pet trade both in expositions and shops and online was assessed. Several crustacean taxa are available both in pet trade exhibitions and online through the Internet. Altogether 26 different species were identified in the aquarium trade in Slovakia. These are Procambarus fallax f. virginalis, P. clarkii, P. alleni, Cherax quadricarinatus, C. destructor, C. holthuisi, C. peknyi, Cambarellus patzcuarensis and C. diminutus occurring in the aquarium pet trade in Slovakia (n = 9. Procambarus fallax f. virginalis, P. clarkii and C. patzuarensis are the most common in this regard. There is also a quantity of other related taxa in the aquarium pet trade in Slovakia, mainly Caridina spp. (n = 5, Neocaridina spp. (n = 4, Atyopsis moluccensis, Atya gabonensis, Arachnochium kulsiense and several taxa of exotic crabs (n = 5 belonging to three different genera (Cardiosoma, Geosesarma and Gecarinus present. Neocaridina davidi is identified as the most frequent in this regard. As some of the species can become established and form viable

Spatial and temporal variations of mercury levels in Okefenokee invertebrates: Southeast Georgia

International Nuclear Information System (INIS)

George, Bagie M.; Batzer, Darold

2008-01-01

Accumulation of mercury in wetland ecosystems has raised concerns about impacts on wetland food webs. This study measured concentrations of mercury in invertebrates of the Okefenokee Swamp in Georgia, focusing on levels in amphipods, odonates, and crayfish. We collected and analyzed total mercury levels in these invertebrates from 32 sampling stations across commonly occurring sub-habitats. Sampling was conducted in December, May, and August over a two-year period. The highest levels of mercury were detected in amphipods, with total mercury levels often in excess of 20 ppm. Bioaccumulation pathways of mercury in invertebrates of the Okefenokee are probably complex; despite being larger and higher in the food chain, levels in odonates and crayfish were much lower than in amphipods. Mercury levels in invertebrates varied temporally with the highest levels detected in May. There was a lack of spatial variation in mercury levels which is consistent with aerial deposition of mercury. - This study measured mercury levels in invertebrates and found the highest levels in amphipods

Tritium behaviour in aquatic plants and animals in a freshwater marsh ecosystem

International Nuclear Information System (INIS)

Adams, L.W.; Peterle, T.J.; White, G.C.

1979-01-01

Ten curies of tritium as tritiated water (HTO) were experimentally added to an enclosed 2-ha Lake Erie marsh on 20 October 1973. Tritium kinetics in selected plants and animals were determined over a one-year period. Tritium levels in the marsh bottom sediment averaged 1.8 times the marsh water levels, with little evidence of tritium concentration above the marsh water tritium levels in the flora and fauna. The unbound tritium: marsh water tritium ratios in smartweed (Polygonum lapathifolium) and pickerelweed (Pontederia cordata) (both emergents) were lower than the same ratio for pondweed (Potamogeton crispus) (a submergent). There was some evidence of bound tritium buildup in midsummer, particularly in the pondweed. Tritium uptake into the unbound compartments of crayfish (Procambarus blandingi), carp (Cyprinus carpio) and bluegills (Lepomis macrochirus) was rapid. For crayfish, maximum HTO levels were observed on days 2 and 3 following treatment for muscle and viscera respectively. Unbound HTO in carp muscle peaked in 4 hours and the level in carp viscera reached a maximum in 2 days, in bluegill muscle and viscera on day 1. Unbound HTO in all species decreased following peak levels, paralleling marsh water HTO activity. Tritium uptake into the bound compartments was not as rapid nor were the levels as high as for unbound HTO in the fauna. The peak bound level in crayfish muscle was observed on day 10 (bound : unbound ratio of 0.34) and the maximum level in viscera was noted on day 20 (bound : unbound ratio of 0.23). Bound tritium in carp muscle and viscera reached maximum levels on day 20 (bound : unbound ratios of 0.25 and 0.39 respectively). In bluegills, peaks were reached on days 5 and 7 (bound : unbound ratios of 0.35 and 0.38 for muscle and viscera respectively). Bound tritium in all species decreased following maximum levels

Herbivore preference for native vs. exotic plants: generalist herbivores from multiple continents prefer exotic plants that are evolutionarily naïve.

Directory of Open Access Journals (Sweden)

Wendy E Morrison

2011-03-01

Full Text Available Enemy release and biotic resistance are competing, but not mutually exclusive, hypotheses addressing the success or failure of non-native plants entering a new region. Enemy release predicts that exotic plants become invasive by escaping their co-adapted herbivores and by being unrecognized or unpalatable to native herbivores that have not been selected to consume them. In contrast, biotic resistance predicts that native generalist herbivores will suppress exotic plants that will not have been selected to deter these herbivores. We tested these hypotheses using five generalist herbivores from North or South America and nine confamilial pairs of native and exotic aquatic plants. Four of five herbivores showed 2.4-17.3 fold preferences for exotic over native plants. Three species of South American apple snails (Pomacea sp. preferred North American over South American macrophytes, while a North American crayfish Procambarus spiculifer preferred South American, Asian, and Australian macrophytes over North American relatives. Apple snails have their center of diversity in South America, but a single species (Pomacea paludosa occurs in North America. This species, with a South American lineage but a North American distribution, did not differentiate between South American and North American plants. Its preferences correlated with preferences of its South American relatives rather than with preferences of the North American crayfish, consistent with evolutionary inertia due to its South American lineage. Tests of plant traits indicated that the crayfish responded primarily to plant structure, the apple snails primarily to plant chemistry, and that plant protein concentration played no detectable role. Generalist herbivores preferred non-native plants, suggesting that intact guilds of native, generalist herbivores may provide biotic resistance to plant invasions. Past invasions may have been facilitated by removal of native herbivores, introduction of

Predation of the alien American mink Mustela vison on native crayfish populations in middle-sized streams in central and western Bohemia

Czech Academy of Sciences Publication Activity Database

Fischer, D.; Pavluvčík, P.; Sedláček, František; Šálek, Martin

2009-01-01

Roč. 58, č. 1 (2009), s. 45-56 ISSN 0139-7893 Institutional research plan: CEZ:AV0Z60870520 Keywords : mink diet * stone crayfish * prey selectivity * density-dependent predation * Czech Republic Subject RIV: EG - Zoology Impact factor: 0.357, year: 2009

Characterizing the Status (Disturbed, Hybrid or Novel) of Swamp Forest Fragments in a Caribbean Ramsar Wetland: The Impact of Anthropogenic Degradation and Invasive Plant Species.

Science.gov (United States)

Prospere, Kurt; McLaren, Kurt P; Wilson, Byron

2016-10-01

The last remaining Amazonian-type swamp forest fragments in Black River Lower Morass, Jamaica, have been subjected to a myriad of anthropogenic disturbances, compounded by the establishment and spread of several invasive plant species. We established 44 permanent sample plots (covering 3.92 ha) across 10 of these swamp forest fragments and sampled all non-woody plants and all trees ≥2 cm DBH found in the plots. These data were used to (1) identify thresholds of hybridity and novelty, (2) derive several diversity and structural descriptors used to characterize the swamp forest fragments and (3) identify possible indicators of anthropogenic degradation. These were incorporated into a framework and used to determine the status of the swamp forest fragments so that appropriate management and conservation measures can be implemented. We recorded 43 woody plant species (9 endemic, 28 native and 4 non-native) and 21 non-tree species. The composition and structure of all the patches differed significantly due to the impact of the herbaceous invasive plant Alpinia allughas, the presence and diversity of other non-native plants, and differing intensities of anthropogenic disturbance (e.g., burning, cutting and harvesting of non-timber forest products). We ranked forest patches along a continuum representing deviations from a historical proxy (least disturbed) swamp forest to those with dramatically altered structural and floristic attributes (=novel swamp forests). Only one fragment overrun with A. allughas was classified as novel. If effective conservation and management does not come to the BRLM, the remaining swamp forest fragments appear doomed to further degradation and will soon disappear altogether.

Mapping Palm Swamp Wetland Ecosystems in the Peruvian Amazon: a Multi-Sensor Remote Sensing Approach

Science.gov (United States)

Podest, E.; McDonald, K. C.; Schroeder, R.; Pinto, N.; Zimmerman, R.; Horna, V.

2012-12-01

Wetland ecosystems are prevalent in the Amazon basin, especially in northern Peru. Of specific interest are palm swamp wetlands because they are characterized by constant surface inundation and moderate seasonal water level variation. This combination of constantly saturated soils and warm temperatures year-round can lead to considerable methane release to the atmosphere. Because of the widespread occurrence and expected sensitivity of these ecosystems to climate change, it is critical to develop methods to quantify their spatial extent and inundation state in order to assess their carbon dynamics. Spatio-temporal information on palm swamps is difficult to gather because of their remoteness and difficult accessibility. Spaceborne microwave remote sensing is an effective tool for characterizing these ecosystems since it is sensitive to surface water and vegetation structure and allows monitoring large inaccessible areas on a temporal basis regardless of atmospheric conditions or solar illumination. We developed a remote sensing methodology using multi-sensor remote sensing data from the Advanced Land Observing Satellite (ALOS) Phased Array L-Band Synthetic Aperture Radar (PALSAR), Shuttle Radar Topography Mission (SRTM) DEM, and Landsat to derive maps at 100 meter resolution of palm swamp extent and inundation based on ground data collections; and combined active and passive microwave data from AMSR-E and QuikSCAT to derive inundation extent at 25 kilometer resolution on a weekly basis. We then compared information content and accuracy of the coarse resolution products relative to the high-resolution datasets. The synergistic combination of high and low resolution datasets allowed for characterization of palm swamps and assessment of their flooding status. This work has been undertaken partly within the framework of the JAXA ALOS Kyoto & Carbon Initiative. PALSAR data have been provided by JAXA. Portions of this work were carried out at the Jet Propulsion Laboratory

Improved open-sun drying method for local swamp rice in Uganda ...

African Journals Online (AJOL)

“Kaiso” and “Supa” are the main local swamp-rice (Oryza Sativa) varieties currently grown in Uganda mainly by smallholder farmers on small gardens (0.5 – 2ha). Due to lack of mechanized drying equipment and owing to the low volumes of their harvests, these farmers use open-sun drying methods, where the paddy is ...

Weathering of a petroleum spill in a tropical mangrove swamp

Energy Technology Data Exchange (ETDEWEB)

Fisher, S.J.; Alexander, R.; Kagi, R.I. [Curtin Univ., Perth (Australia)

1996-12-31

In August 1987, an indeterminate amount of petroleum condensate was released from a buried pipe leading to contamination of a tropical mangrove swamp surrounding a tidal creek in North Western Australia. Since no bioremediation was attempted at this site, we have monitored the natural weathering of the condensate by detailed analysis of the petroleum hydrocarbons extracted from sediment samples collected on 11 occasions over a 3 year period.

Comparing Avocado, Swamp Bay, and Camphortree as Hosts of Raffaelea lauricola Using a Green Fluorescent Protein (GFP)-Labeled Strain of the Pathogen.

Science.gov (United States)

Campbell, A S; Ploetz, R C; Rollins, J A

2017-01-01

Raffaelea lauricola, a fungal symbiont of the ambrosia beetle Xyleborus glabratus, causes laurel wilt in members of the Lauraceae plant family. North American species in the family, such as avocado (Persea americana) and swamp bay (P. palustris), are particularly susceptible to laurel wilt, whereas the Asian camphortree (Cinnamomum camphora) is relatively tolerant. To determine whether susceptibility is related to pathogen colonization, a green fluorescent protein-labeled strain of R. lauricola was generated and used to inoculate avocado, swamp bay, and camphortree. Trees were harvested 3, 10, and 30 days after inoculation (DAI), and disease severity was rated on a 1-to-10 scale. By 30 DAI, avocado and swamp bay developed significantly more severe disease than camphortree (mean severities of 6.8 and 5.5 versus 1.6, P < 0.003). The extent of xylem colonization was recorded as the percentage of lumena that were colonized by the pathogen. More xylem was colonized in avocado than camphortree (0.9% versus 0.1%, P < 0.03) but colonization in swamp bay (0.4%) did not differ significantly from either host. Although there were significant correlations between xylem colonization and laurel wilt severity in avocado (r = 0.74), swamp bay (r = 0.82), and camphortree (r = 0.87), even severely affected trees of all species were scarcely colonized by the pathogen.

Heavy Metals Uptake by Asian Swamp Eel, Monopterus albus from Paddy Fields of Kelantan, Peninsular Malaysia: Preliminary Study

OpenAIRE

Yin, Sow Ai; Ismail, Ahmad; Zulkifli, Syaizwan Zahmir

2012-01-01

Swamp eel, Monopterus albus is one of the common fish in paddy fields, thus it is suitable to be a bio-monitor for heavy metals pollution studies in paddy fields. This study was conducted to assess heavy metals levels in swamp eels collected from paddy fields in Kelantan, Malaysia. The results showed zinc [Zn (86.40 μg/g dry weight)] was the highest accumulated metal in the kidney, liver, bone, gill, muscle and skin. Among the selected organs, gill had the highest concentrations of lead (Pb),...

Appropriate Usage Level of Shrimp Waste Meal as Chitin Source for Feeding Young Crayfish (Astacus leptodactylus Esch. 1823

Directory of Open Access Journals (Sweden)

Seval Bahadır Koca*, Nalan Ozgur Yigit, Arife Dulluc, Gonca Erol1, Nihal Cılbız1 and Ramazan Kucukkara1

2011-06-01

Full Text Available This study was conducted to determine effects of shrimp waste meal as natural chitin source at different rates (0 (control, 10, 20, 30 and 40% on growth, feed conversion ratio (FCR, survival of young crayfish (1.61±0.04 g and 3.74±0.03 cm for 60 days. Fifteen glass aquariums (70x30x40 cm were used in the experiment and 20 individuals were stocked per aquarium (95/m2. The highest of final weight and weight gain were obtained in feed with 10% shrimp waste meal group (3.29±0.23 and 1.66±0.23 g, while the lowest of final weight and weight gain was obtained in fed with 40% shrimp waste meal group (2.75±0.35 and 1.18±0.37 g, respectively. However, non-significant differences were found between final weight, weight gain, specific growth rate, final total length, feed conversion ratio, survival percentage among groups at the end of experimental period. It was concluded that shrimp waste meal as natural chitin source can be used in young crayfish diets up to 40% without adverse effect influence on growth.

Spatial differences in hydrologic characteristics and water chemistry of a temperate coastal plain peatland: The Great Dismal Swamp, USA

Science.gov (United States)

Speiran, Gary K.; Wurster, Frederick C.

2016-01-01

Spatial differences in hydrologic processes and geochemistry across forested peatlands control the response of the wetland-community species and resiliency to natural and anthropogenic disturbances. Knowing these controls is essential to effectively managing peatlands as resilient wetland habitats. The Great Dismal Swamp is a 45,325 hectare peatland in the Atlantic Coastal Plain of Virginia and North Carolina, USA, managed by the U.S. Fish and Wildlife Service. The existing forest-species distribution is a product of timber harvesting, hydrologic alteration by canal and road construction, and wildfires. Since 2009, studies of hydrologic and geochemical controls have expanded knowledge of groundwater flow paths, water chemistry, response to precipitation events, and characteristics of the peat. Dominant hydrologic and geochemical controls include (1) the gradual slope in land surface, (2) vertical differences in the hydraulic characteristics of the peat, (3) the proximity of lateral groundwater and small stream inflows from uplands, (4) the presence of an extensive canal and road network, and (5) small, adjustable-height dams on the canals. Although upland sources provide some surface water and lateral groundwater inflow to western parts of the swamp, direct groundwater recharge by precipitation is the major source of water throughout the swamp and the only source in many areas. Additionally, the proximity and type of upland water sources affect water levels and nutrient concentrations in canal water and groundwater. Where streams are a dominant upland source, variations in groundwater levels and nutrient concentrations are greater than where recharge by precipitation is the primary water source. Where upland groundwater is a dominant source, water levels are more stable. Because the species distribution of forest communities in the Swamp is strongly influenced by these controls, swamp managers are beginning to incorporate this knowledge into forest, water, and fire

75 FR 8107 - Bond Swamp National Wildlife Refuge, Bibb and Twiggs Counties, GA

Science.gov (United States)

2010-02-23

... impact. SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce the availability of our final comprehensive Conservation Plan (CCP) and finding of no significant impact (FONSI) for the environmental..., including upland mixed pine/hardwood, bottomland hardwood, and tupelo gum swamp forests. Creeks, beaver...

The palynology and sedimentology of a coastal swamp at Awana, Great Barrier Island, New Zealand, from c. 7000 yr B.P. to present

International Nuclear Information System (INIS)

Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

1999-01-01

Pollen and sediment analysis of two Holocene cores from Awana, Great Barrier Island, shows that at 7000 calibrated yr B.P. the local swamp was an estuarine salt marsh dominated by Restionaceae. By c. 6000 yr B.P. the water table was lower, and a fresh water swamp (Gleichenia-Leptospermum) had replaced the salt marsh. Regional conifer-hardwood forest c. 7000 yr B.P. was initially co-dominated by Libocedrus and Dacrydium cupressinum. Libocedrus declined from c. 6000 yr B.P. During the period c. 6000-c. 2500 yr B.P., relatively stable environmental conditions ensued with little change in local or regional vegetation. Around 2500 yr B.P., the swamp surface became drier and was invaded by Dacrycarpus and Laurelia swamp forest. This forest was subsequently repeatedly disturbed (not by fire), indicating climatic change to drier and windier conditions. Ascarina lucida was periodically a major component of swamp forest. Disturbance is also recorded in the clastic (mineral) sediments, where beds of sand within finer-grained sediment and peat are interpreted as wind blown material derived from partly devegetated dunes to seaward. The presence of the Kaharoa Tephra allows the timing of major Polynesian deforestation at Awana to be reliably dated to c. 600 calibrated yr B.P. In contrast, we see no evidence in the clastic sediment record of disturbance at Awana since Kaharoa time. We attribute this to the maintenance of stable dunes by a herb/scrub cover despite nearby fires, or to the presence of scrub or forest buffering the swamp from ablating dunes. (author). 45 refs., 4 figs., 1 tab

Behavioural and hormonal aspects of the oestrous cycle in swamp buffaloes reared under temperate conditions

International Nuclear Information System (INIS)

Kanai, Y.; Ishikawa, N.; Shimizu, H.

1990-01-01

A series of experiments was carried out using a small herd of swamp buffaloes raised in Japan under temperate conditions at 36 deg. N latitude, with a view to determining whether they exhibit peculiar characteristics in their oestrous cycles. The studies on the oestrous behaviour revealed that under adequate feeding and management conditions, buffaloes regularly display oestrous throughout the year, with the cycle length, duration of oestrous and time of ovulation all falling within ranges similar to those reported in cattle. External signs of oestrus were generally less evident, as previously reported. Hormonal analysis showed that there were no remarkable differences between swamp buffaloes and cattle in terms of the secretory patterns of pituitary gonadotrophins and ovarian steroids during the oestrous cycle. (author). 13 refs, 2 figs

Lunar-Rhythmic Molting in Laboratory Populations of the Noble Crayfish Astacus astacus (Crustacea, Astacidea): An Experimental Analysis

Science.gov (United States)

Franke, Robert; Hoerstgen-Schwark, Gabriele

2013-01-01

Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing “summer conditions” (LD 16:8, 19°C). Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at “new moons”. Males showed a slightly higher degree of synchronization than females. A phase-shift of the artificial lunar cycle in relation to the natural cycle resulted in a corresponding shift of the molting cycle. This clearly demonstrates that changes in the nocturnal light regime provide the primary external information for the lunar-monthly molting rhythm. There is a first indication that lunar photic stimuli do not act directly but as a zeitgeber which entrains an endogenous molting rhythm to the lunar cycle. Moreover, the results of the long-term experiments suggest that the hibernal resting period of A . astacus in the field (no molts between October and April) may also involve some endogenous programming. Continuing artificial summer conditions can delay but not completely suppress this resting period. The adaptive significance of the phenomena and how the findings may be applied to improve the management of crowded crayfish stocks are discussed. PMID:23840899

Repeated drought alters resistance of seed bank regeneration in baldcypress swamps of North America

Science.gov (United States)

Lei, Ting; Middleton, Beth A.

2018-01-01

Recurring drying and wetting events are likely to increase in frequency and intensity in predicted future droughts in the central USA and alter the regeneration potential of species. We explored the resistance of seed banks to successive droughts in 53 sites across the nine locations in baldcypress swamps in the southeastern USA. Along the Mississippi River Alluvial Valley and northern Gulf of Mexico, we investigated the capacity of seed banks to retain viable seeds after successive periods of drying and wetting in a greenhouse study. Mean differences in species richness and seed density were compared to examine the interactions of successive droughts, geographical location and water regime. The results showed that both species richness and total density of germinating seedlings decreased over repeated drought trials. These responses were more pronounced in geographical areas with higher annual mean temperature. In seed banks across the southeastern swamp region, most species were exhausted after Trial 2 or 3, except for semiaquatic species in Illinois and Tennessee, and aquatic species in Texas. Distinct geographical trends in seed bank resistance to drought demonstrate that climate-induced drying of baldcypress swamps could influence the regeneration of species differently across their ranges. Despite the health of adult individuals, lack of regeneration may push ecosystems into a relict status. Seed bank depletion by germination without replenishment may be a major conservation threat in a future with recurring droughts far less severe than megadrought. Nevertheless, the protection of moist refugia might aid conservation.

Holocene mangrove swamps of West Africa sedimentology and soils

Science.gov (United States)

Marius, C.; Lucas, J.

The mangrove swamps of West African Coast belong to the Atlantic type which is characterized by a small number of species. They colonize tidal environments which are dissected by numerous meandering tidal channels and are presently subject to a low rate of sediment accumulation. The mangrove vegetation exhibits a characteristic zonation pattern that basically reflects the adaptation of the various species to saline conditions. The typical zonation sequence is: Rhizophora racemosa (or Rh. mangle), Rh. mangle + Avicennia africana, Avicennia, flooded tanne, barren tanne, herbaceous tanne. The tannes are generated by aridic climatic conditions, heavy soil and water salt content, and are, in a way a peculiar feature of mangrove swamps in West Africa. The sediment colonized by the mangroves is relatively homogenous. Mineralogically, they are dominated by quartz and clay to which are associated halite, pyrite and jarosite. The clay suite is mainly composed of smectite and kaolinite. Smectite is predominant in the inlet areas and is replaced inland by kaolinite. Chemically, the sediments contain very low amounts of Ca, bases and trace elements. The mangrove swamp floodwaters have a chemical composition similar to that of seawater. It is dominated by sodium and chloride. Morphologically, the ripening of the soils appears with a chestnut mash colour horizon and buttery consistency in relation with the decomposition of fibrous roots of Rhizophora and also with pale yellow jarosite mottles in the top horizons of the tanne profiles due to the oxidation of pyrine. The two main properties of the mangrove soils of West Africa are acidity and salinity; the first is related to the high content of sulphur and the second to the sea influence. The acidity has to be connected mainly to the Rhizophora vegetation whose the root system is a real trap for catching the pyrites resulting from the reduction of the sulphates of sea water by the sulphate reducing bacteria, in a reduced

Do environmental changes or juvenile competition act as mechanisms of species displacement in crayfishes?

Science.gov (United States)

Westhoff, Jacob T.; DiStefano, R.J.; Magoulick, D.D.

2012-01-01

The Big Creek Crayfish, Orconectes peruncus, is native to the St. Francis River drainage in Missouri, USA and is often absent where the introduced Woodland Crayfish, Orconectes hylas, has established. We performed a field experiment to determine whether effects of current abiotic conditions and interspecific competition with O. hylas were responsible for displacement of O. peruncus from parts of their former range. We examined growth and survival of juvenile male O. peruncus exposed to juvenile male O. hylas in enclosures at two sites in the former range of O. peruncus. Enclosures contained 8 (low density) or 16 individuals (high density) and had O. peruncus only (control) or both species (interspecific treatment). Juvenile O. peruncus were able to survive and grow in portions of their former range, implicating biotic versus abiotic factors in the displacement of O. peruncus. Survival rates of O. peruncus did not differ among treatments at either site. Orconectes peruncus showed significant growth in all treatments and interspecific effects were not greater than intraspecific effects on O. peruncus growth rates. High-density treatments showed significantly reduced O. peruncus growth rates compared to low-density treatments, except in Carver Creek interspecific treatments. When considered in the context of previous studies examining the effects of O. hylas on O. peruncus, results suggest that neither direct competition between juvenile males of the two species or abiotic change are responsible for the decreased range of O. peruncus. Additional research is required to determine the mechanism(s) driving the displacement of O. peruncus. ?? 2011 Springer Science+Business Media B.V.

Relationships between Vacant Homes and Food Swamps: A Longitudinal Study of an Urban Food Environment.

Science.gov (United States)

Mui, Yeeli; Jones-Smith, Jessica C; Thornton, Rachel L J; Pollack Porter, Keshia; Gittelsohn, Joel

2017-11-21

Research indicates that living in neighborhoods with high concentrations of boarded-up vacant homes is associated with premature mortality due to cancer and diabetes, but the mechanism for this relationship is unclear. Boarded-up housing may indirectly impact residents' health by affecting their food environment. We evaluated the association between changes in vacancy rates and changes in the density of unhealthy food outlets as a proportion of all food outlets, termed the food swamp index, in Baltimore, MD (USA) from 2001 to 2012, using neighborhood fixed-effects linear regression models. Over the study period, the average food swamp index increased from 93.5 to 95.3 percentage points across all neighborhoods. Among non-African American neighborhoods, increases in the vacancy rate were associated with statistically significant decreases in the food swamp index (b = -0.38; 90% CI, -0.64 to -0.12; p -value: 0.015), after accounting for changes in neighborhood SES, racial diversity, and population size. A positive association was found among low-SES neighborhoods (b = 0.15; 90% CI, 0.037 to 0.27; p -value: 0.031). Vacant homes may influence the composition of food outlets in urban neighborhoods. Future research should further elucidate the mechanisms by which more distal, contextual factors, such as boarded-up vacant homes, may affect food choices and diet-related health outcomes.

Strong and stable geographic differentiation of swamp buffalo maternal and paternal lineages indicates domestication in the China/Indochina border region.

Science.gov (United States)

Zhang, Yi; Lu, Yongfang; Yindee, Marnoch; Li, Kuan-Yi; Kuo, Hsiao-Yun; Ju, Yu-Ten; Ye, Shaohui; Faruque, Md Omar; Li, Qiang; Wang, Yachun; Cuong, Vu Chi; Pham, Lan Doan; Bouahom, Bounthong; Yang, Bingzhuang; Liang, Xianwei; Cai, Zhihua; Vankan, Dianne; Manatchaiworakul, Wallaya; Kowlim, Nonglid; Duangchantrasiri, Somphot; Wajjwalku, Worawidh; Colenbrander, Ben; Zhang, Yuan; Beerli, Peter; Lenstra, Johannes A; Barker, J Stuart F

2016-04-01

The swamp type of the Asian water buffalo is assumed to have been domesticated by about 4000 years BP, following the introduction of rice cultivation. Previous localizations of the domestication site were based on mitochondrial DNA (mtDNA) variation within China, accounting only for the maternal lineage. We carried out a comprehensive sampling of China, Taiwan, Vietnam, Laos, Thailand, Nepal and Bangladesh and sequenced the mtDNA Cytochrome b gene and control region and the Y-chromosomal ZFY, SRY and DBY sequences. Swamp buffalo has a higher diversity of both maternal and paternal lineages than river buffalo, with also a remarkable contrast between a weak phylogeographic structure of river buffalo and a strong geographic differentiation of swamp buffalo. The highest diversity of the swamp buffalo maternal lineages was found in south China and north Indochina on both banks of the Mekong River, while the highest diversity in paternal lineages was in the China/Indochina border region. We propose that domestication in this region was later followed by introgressive capture of wild cows west of the Mekong. Migration to the north followed the Yangtze valley as well as a more eastern route, but also involved translocations of both cows and bulls over large distances with a minor influence of river buffaloes in recent decades. Bayesian analyses of various migration models also supported domestication in the China/Indochina border region. Coalescence analysis yielded consistent estimates for the expansion of the major swamp buffalo haplogroups with a credibility interval of 900 to 3900 years BP. The spatial differentiation of mtDNA and Y-chromosomal haplotype distributions indicates a lack of gene flow between established populations that is unprecedented in livestock. © 2015 John Wiley & Sons Ltd.

Differential recovery of a deepwater swamp forest across a gradient of disturbance intensity

Science.gov (United States)

Diane De Steven; Rebecca R. Sharitz

1997-01-01

On the Savannah River Site, South Carolina, USA, large areas of floodplain swamp forest of baldcypress (Taxodium distichum) and water tupelo (Nyssa aquatica) were destroyed by the cumulative impacts of cooling-water discharges over a 35-year period of nuclear reactor operations. In one floodplain area, four years after thermal...

Importance of small fishes and invasive crayfish in otter Lutra lutra diet in an English chalk stream

OpenAIRE

Britton, J.R.; Berry, M.; Sewell, S.; Lees, C.; Reading, P.

2017-01-01

The diet composition of the European otter Lutra lutra was assessed using spraint analysis in the Hampshire Avon, a lowland chalk stream in Southern England, over an 18-month period. Small cyprinid fishes were the main prey item taken in all seasons, with bullhead Cottus gobio and stone loach Barbatula barbatula also important; there were relatively few larger fishes of interest to fisheries found. There were significant seasonal differences in diet composition by season, with signal crayfish...

CRAYFISH PREDATION EXPERIMENTS ON THE INTRODUCED ZEBRA MUSSEL, DREISSENA POLYMORPHA, IN IRELAND, AND THEIR POTENTIAL FOR BIOCONTROL.

OpenAIRE

REYNOLDS J. D.; DONOHOE R.

2001-01-01

The zebra mussel Dreissena polymorpha, native to the Aralo-Caspian region, has spread across Europe in the last 180 years. Although it reached England in 1820, it only arrived in Ireland in around 1995, probably attached to the hull of pleasure boats, and since then has spread through the lowland Shannon and Erne systems, which are linked by canal. While White-clawed crayfish Austropotamobius pallipes (Lereboullet) occur in these systems, Dreissena has not yet colonized sites with large crayf...

Comparative palynomorph signals of vegetation change preserved in an adjacent peat swamp and estuary in north-west Nelson, New Zealand

International Nuclear Information System (INIS)

Armour, R.K.; Kennedy, D.M.

2005-01-01

A history of vegetation for the mid-late Holocene was extracted from the southern margins of Whanganui Inlet and Mangarakau Swamp. These two sites represent very different pollen sinks with the estuary being dominated by fluvially transported material and the swamp by in situ pollen rain. They are, however, located very close to each other and therefore provide a unique study area to investigate how differing source environments affect pollen signals. A vegetation change from podocarps to beech forest is recorded in both settings at around 4000 years CalBP which is similar to that recorded at higher altitudes in the region. Robust palynomorphs were found in greater abundance in the inlet while the swamp contained a higher proportion of wetland species. Despite these differences both environments appeared to record a similar regional vegetation signal. This shows that estuarine environments, often characterised by material that has been transported, can provide accurate reconstructions of vegetation change. (author). 31 refs., 8 figs., 1 tab

BIOCONTROL FOR RHIZOCTONIA STEM ROT DISEASE BY USING COMBINATION OF SPECIFIC ENDOPHYTE IN PADDY TIDAL SWAMP

Directory of Open Access Journals (Sweden)

Ismed Setya Budi

2013-10-01

Full Text Available The use of combination of specific endophytic in tidal swamps to control stem root disease as biological control agents has not been done. It is expected that this combination is able to continuously protect plants from pathogen interference. The research was carried out in type C tidal swamp in Banjar regency of South Kalimantan, from March to November 2011, temperature 29-32oC, and pH 4.0-5.5. The method used was Split Plot design. Biocontrol preparation for both types of endophytic was applied in seeds in 7 days after planting (DAP. Observation on high intensity and plant diseases of planting stage on tidal swamps (taradak, ampak and lacak was conducted. The results showed that there was a reduction of disease ranging from 58.70 to 87.29%. The application of combination of two biocontrol agents (T. viride PS-2.1 + P. fluorescent PS-4.8, (Fusarium non-pathogenic PS-1.5 + P. fluorescent PS-4.8 and (T. viride PS-2.1+ FNP PS-1.5 isolate gave the best inhibition result, reduced disease intensity, and increased plant height. The result of soil analysis before and after application of endophytic showed that there was an increase in soil fertility with the element addition of N, P, K and pH.

AGRICULTURE PHENOMENA AND PERSPECTIVES OF LEBAK SWAMP IN JAKABARING SOUTH SUMATRA, INDONESIA

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Elisa Wildayana

2017-11-01

Full Text Available The research aimed to analyze agriculture phenomena and perspectives of lebak swamp in Jakabaring South Sumatra Indonesia. The research used mix methods of quantitative and qualitative approaches. The description of the research area was assisted with interpretation of Landsat images in 1987 and 2015. The research resulted that farmer’s groups living in Jakabaring are divided into four group, namely indigenous people (people of Ogan, Komering, Musi, Enim, and Palembang, new comers (Javanese, spontaneous migration (Buginese, Banjarnese, Bataknese and outside spontaneous migration (Chinese, Arabic. The total area of Jakabaring is approximately 5,525 ha, around 2,700 ha (48.87 % was already landfilled by the Government in 1990, while the remaining 2,825 ha (51.13 % is still not reclaimed. The landfill materials were directly sucked from mud, sand, silt and stones of the Musi River. Each lebak swamp typology shows specific soil characters, but after landfills all soils became homogenous because of uniform materials of landfills. Patterns of land degradation after landfills are classified into three groups, namely making layers of water impermeability, changing vegetation types of land cover, and decreasing type and density of vegetation.

Potential roles of fish, birds, and water in swamp privet (Forestiera acuminata) seed dispersal

Science.gov (United States)

Susan B. Adams; Paul B. Hamel; Kristina Connor; Bryce Burke; Emile S. Gardiner; David Wise

2007-01-01

Forestiera acuminata (swamp privet) is a common wetland shrub/small tree native to the southeastern United States. We examined several possible dispersal avenues for the plant. We tested germination of seeds exposed to various treatments, including passage through Ictalurus punctatus (Channel Catfi sh) guts, and conducted other...

Yellow perch larval survival in the Zekiah Swamp watershed (Wicomico River, Maryland) relative to the potential effects of a coal ash storage facility

International Nuclear Information System (INIS)

Burton, W.H.; Pinkney, A.E.

1994-01-01

A coordinated program of in situ and laboratory bioassays supported by water quality analyses was used to evaluate the potential effect of a coal ash storage facility on a yellow perch (Perca flavescens) spawning area. The facility is located in the Zekiah Swamp watershed, a tributary of the Wicomico River, MD. In situ bioassays were conducted in Zekiah Swamp Run and reference locations in 1989 and 1990. Larval mortality was high in non-tidal areas of Zekiah Swamp Run, both at a site upstream and beyond the influence of the facility, and at a site downstream of the facility. Mortality was significantly less at a nearby reference stream and at a station in the tidal area of Zekiah Swamp Run. Analysis of water samples for metals (including inorganic monomeric aluminum), organic contaminants, and pH, as well as measurements of stream flow, did not identify a specific cause for the mortality. The field and laboratory bioassays showed that, although leachate from the ash facility contributed to local contamination of ground water, the facility does not appear to be responsible for the poor survival of larval yellow perch. 16 refs., 4 figs., 6 tabs

Effect of calcium on excitatory neuromuscular transmission in the crayfish

Science.gov (United States)

Bracho, H.; Orkand, R. K.

1970-01-01

1. The effects of varying the external Ca concentration from 1·8 to 30 mM/l. (⅛-2 times normal) have been studied at the in vitro crayfish excitatory neuromuscular junction. Electrophysiological techniques were used to record transmembrane junctional potentials from muscle fibres and extracellular junctional currents from the vicinity of nerve terminals. 2. The excitatory junctional potential amplitude was proportional to [Ca]0n, where n varied between 0·68 and 0·94 (mean 0·82) when [Ca]0 was varied from 1·8 to 15 mM/l. 3. The increase in junctional potential amplitude on raising [Ca]0 resulted primarily from an increase in the average number of quanta of excitatory transmitter released from the presynaptic nerve terminal by the nerve impulse. 4. The size of the quanta, synaptic delay, presynaptic potential and electrical properties of the muscle membrane were little affected by changes in calcium concentration in the range studied. PMID:5498460

Spatial analysis of Carbon-14 dynamics in a wetland ecosystem (Duke Swamp, Chalk River Laboratories, Canada)

International Nuclear Information System (INIS)

Yankovich, T.L.; King-Sharp, K.J.; Carr, J.; Robertson, E.; Killey, R.W.D.; Beresford, N.A.; Wood, M.D.

2014-01-01

A detailed survey was conducted to quantify the spatial distribution of 14 C in Sphagnum moss and underlying soil collected in Duke Swamp. This wetland environment receives 14 C via groundwater pathways from a historic radioactive Waste Management Area (WMA) on Atomic Energy Canada Limited (AECL)'s Chalk River Laboratories (CRL) site. Trends in 14 C specific activities were evaluated with distance from the sampling location with the maximum 14 C specific activity (DSS-35), which was situated adjacent to the WMA and close to an area of groundwater discharge. Based on a spatial evaluation of the data, an east-to-west 14 C gradient was found, due to the influence of the WMA on 14 C specific activities in the swamp. In addition, it was possible to identify two groups of sites, each showing significant exponential declines with distance from the groundwater source area. One of the groups showed relatively more elevated 14 C specific activities at a given distance from source, likely due to their proximity to the WMA, the location of the sub-surface plume originating from the WMA, the presence of marsh and swamp habitat types, which facilitated 14 C transport to the atmosphere, and possibly, 14 C air dispersion patterns along the eastern edge of the swamp. The other group, which had lower 14 C specific activities at a given distance from the groundwater source area, included locations that were more distant from the WMA and the sub-surface plume, and contained fen habitat, which is known to act as barrier to groundwater flow. The findings suggest that proximity to source, groundwater flow patterns and habitat physical characteristics can play an important role in the dynamics of 14 C being carried by discharging groundwater into terrestrial and wetland environments. - Highlights: • Groundwater represents an important source of volatile radionuclides to wetlands. • Habitat type influenced 14 C transport from sub-surface to surface environments. • C-14 specific

Composition and species diversity of pine-wiregrass savannas of the Green Swamp, North Carolina

Science.gov (United States)

Joan Walker; Robert K. Peet

1983-01-01

Fire-maintained, species-rich pines wiregrass savannas in the Green Swamp, North Carolina were sampled over their natural range of environmental conditions and fire frequencies. Species composition, species richness, diversity (Exp H', I/ C), and aboveground production were documented and fertilization experiments conducted to assess possible mechanisms for the...

Recycling of phenolic compounds in Borneo's tropical peat swamp forests.

Science.gov (United States)

Yule, Catherine M; Lim, Yau Yan; Lim, Tse Yuen

2018-02-07

Tropical peat swamp forests (TPSF) are globally significant carbon stores, sequestering carbon mainly as phenolic polymers and phenolic compounds (particularly as lignin and its derivatives) in peat layers, in plants, and in the acidic blackwaters. Previous studies show that TPSF plants have particularly high levels of phenolic compounds which inhibit the decomposition of organic matter and thus promote peat accumulation. The studies of phenolic compounds are thus crucial to further understand how TPSF function with respect to carbon sequestration. Here we present a study of cycling of phenolic compounds in five forests in Borneo differing in flooding and acidity, leaching of phenolic compounds from senescent Macaranga pruinosa leaves, and absorption of phenolics by M. pruinosa seedlings. The results of the study show that total phenolic content (TPC) in soil and leaves of three species of Macaranga were highest in TPSF followed by freshwater swamp forest and flooded limestone forest, then dry land sites. Highest TPC values were associated with acidity (in TPSF) and waterlogging (in flooded forests). Moreover, phenolic compounds are rapidly leached from fallen senescent leaves, and could be reabsorbed by tree roots and converted into more complex phenolics within the leaves. Extreme conditions-waterlogging and acidity-may facilitate uptake and synthesis of protective phenolic compounds which are essential for impeded decomposition of organic matter in TPSF. Conversely, the ongoing drainage and degradation of TPSF, particularly for conversion to oil palm plantations, reverses the conditions necessary for peat accretion and carbon sequestration.

Testate amoebae analysis in the peat deposits of the swamp Dolgon’koye in the south of Western Siberia and peatland paleohydrology for last 3100 years

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Kurina, Irina V.; Blyakharchuk, Tatiana A.

2018-03-01

Our research is devoted to paleohydrological reconstruction in the swamp located in the river valley on the piedmont of the Altai Mountains in the south of Western Siberia. The reconstruction was carried out based on rhizopod analysis for the last 3100 cal yr. A large amount of different testate amoebae was found in the peat. Total 64 testate amoebae taxa were recorded in the peat core with the most abundant being: Trinema lineare, Centropyxis aculeata, C. aerophila, Euglypha rotunda, Cryptodifflugia sp. Decrease of surface wetness in the swamp are observed 2280, 2140, 1900–600 cal yr BP and increase – in 2700, 2500–1900, 230–215 cal yr BP. The results of our reconstruction of the swamp paleohydrology agrees well with the paleoclimatic data obtained earlier for the central area of the south of Western Siberia Plain. It indicates a high sensitivity of the swamp to climatic changes in the Holocene. The rhizopod analysis proved to be very effective when used for paleohydrology reconstruction in minerotrophic peat.

Feeding habits of the genet Genetta genetta in an Iberian continental wetland

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Maite Sánchez

2009-02-01

Full Text Available Abstract This study quantified the diet of the genet Genetta genetta in an Iberian continental wetland, the Galachos Nature Reserve, northern Spain, based on the frequency with which items appeared in five monthly-surveyed latrines during 2004-2005. Prey types were identified de visu using identification keys and expert advice. the genet was confirmed as an opportunistic and generalist predator, its diet including mammals (95.0%, plants (68.3% and arthropods (60.0% as main prey. With the exception of a newly available prey species, the alien crayfish Procambarus clarkii, the genet probably consumed arthropods because of chance encounters rather than active search. The consumption of fruits and small mammals varied seasonally. Riassunto Alimentazione della genetta Genetta genetta in un'area umida continentale della penisola iberica La dieta della genetta è stata investigata in un'area umida interna della Spagna settentrionale, la riserva Naturale dei Galachos. La frequenza di ciascuna categoria alimentare è stata espressa come numero di occorrenze mansili in cinque latrine monitorate per il periodo 2004-2005. Le categorie sono state identificate de visu tramite chiavi per il riconoscimento o l'intervento di singoli esperti. I risultati confermano il comportamento alimentare generalista e opportunista della genetta. La dieta ha incluso principalmente mammiferi (95%, vegetali (68.3% e artropodi (60%. Questi ultimi, con l'eccezione del gambero Procambarus clarkii, introdotto e di recente presenza, sono probabilmente utilizzati in modo opportunistico, piuttosto che in seguito a ricerca attiva. L'uso dei frutti e dei micromammiferi varia stagionalmente.

SWAMP+: multiple subsequence alignment using associative massive parallelism

Energy Technology Data Exchange (ETDEWEB)

Steinfadt, Shannon Irene [Los Alamos National Laboratory; Baker, Johnnie W [KENT STATE UNIV.

2010-10-18

A new parallel algorithm SWAMP+ incorporates the Smith-Waterman sequence alignment on an associative parallel model known as ASC. It is a highly sensitive parallel approach that expands traditional pairwise sequence alignment. This is the first parallel algorithm to provide multiple non-overlapping, non-intersecting subsequence alignments with the accuracy of Smith-Waterman. The efficient algorithm provides multiple alignments similar to BLAST while creating a better workflow for the end users. The parallel portions of the code run in O(m+n) time using m processors. When m = n, the algorithmic analysis becomes O(n) with a coefficient of two, yielding a linear speedup. Implementation of the algorithm on the SIMD ClearSpeed CSX620 confirms this theoretical linear speedup with real timings.

Structure of the tree stratum of three swamp forest communities in southern Brazil under different soil conditions

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Luciana Carla Mancino

2015-03-01

Full Text Available Restinga forests are commonly known to be plant communities rather poor in tree species. This study aimed to describe and explain the association between the floristic-structural similarities and the environmental conditions in three Swamp Restinga Forest communities in southern Brazil. In 13 plots of 100 m2 each, we sampled all individual trees (circumference at breast height >12 cm and height ≥3 m. We collected soil samples in each plot for chemical and textural analyses. Phytosociological parameters were calculated and different structural variables were compared between areas. The density of individuals did not differ between areas; however, the maximum height and abundance of species differed between the site with Histosols and the other two sites with Gleysols. Further, a canonical correspondence analysis based on a matrix of vegetation and that of environmental characteristics explained 31.5% of the total variation. The high floristic and environmental heterogeneity indicate that swamp-forests can shelter many species with low frequency. Most species were generalists that were not exclusive to this type of forest. Overall, our study showed that swamp-forests within the same region can show considerable differences in composition and structure and can include species-rich communities, mostly due to the presence of species with a broader distribution in the Atlantic Rainforest domain on sites with less stressful environmental conditions and without waterlogged conditions.

Tritium kinetics in a freshwater marsh ecosystem

International Nuclear Information System (INIS)

Adams, L.W.

1976-01-01

Ten curies of tritium (as tritiated water, HTO) were applied to a 2-ha enclosed Lake Erie marsh in northwestern Ohio on 29 October 1973. Tritium kinetics in the marsh water, bottom sediment, and selected aquatic plants and animals were determined. Following HTO application, peak tritium levels in the sediment were observed on day 13 in the top 1-cm layer, on day 27 at the 5-cm depth, and on day 64 at the 10-cm depth. Peak levels at 15 and 20 cm were not discernible, although there was some movement of HTO to the 20-cm depth. A model based on diffusion theory described tritium movement through the sediment. Unbound and bound tritium levels in curly-leaf pondweed (Potamogeton crispus), pickerelweed (Pontederia cordata), and smartweed (Polygonum lapathifolium) generally tended to follow tritium levels in marsh water. The unbound tritium:marsh water tritium ratio was significantly larger (P < 0.001) in curly-leaf pondweed than in either of the two emergents. Tritium uptake into the unbound compartments of crayfish (Procambarus blandingi), carp (Cyprinus carpio), and bluegills (Lepomis macrochirus) was rapid. For crayfish, maximum HTO levels were observed on days 3 and 2 for viscera and muscle, respectively. Unbound HTO in carp viscera peaked on day 2, and levels in carp muscle reached a maximum in 4 hours. Maximum levels of unbound HTO in bluegill viscera and muscle were observed on day 1. After peak levels were obtained, unbound HTO paralleled marsh water HTO activity in all species. Tritium uptake into the bound compartments was not as rapid nor were the levels as high as for unbound HTO in any of the species. Peak bound levels in crayfish viscera were observed on day 20 and maximum levels in muscle were noted on day 10. Bound tritium in carp viscera and muscle reached maximum levels on day 20. In bluegills, peaks were reached on days 7 and 5 for viscera and muscle, respectively. Bound tritium in all species decreased following maximum levels

Nariva Swamp Ramsar Site, Trinidad and Tobago (West Indies) Wetland Habitat Restoration Initiative

Science.gov (United States)

Montserrat Carbonell; Nadra Nathai-Gyan

2005-01-01

Trinidad and Tobago, a twin island nation, is the most southerly of the Caribbean islands and lies just 11 km off the coast of Venezuela, near the Orinoco delta. Trinidad, the larger of the two islands, is approximately 5,000 km² and the Nariva Swamp is located on its eastern coast (fig. 1). In 1993, this site was designated as a wetland of international...

Response Function of the Crayfish Caudal Photoreceptor to Hydrodynamic Stimuli

Science.gov (United States)

Breite, Sally; Bahar, Sonya; Neiman, Alexander; Moss, Frank

2002-03-01

In its abdominal 6th ganglion the crayfish houses 2 light-sensitive neurons (caudal photoreceptors, or CPRs). It is known that these neurons work in tandem with a mechanosensory system of tiny hairs spread across the tailfan, which make synaptic contact with the photoreceptors. A stochastic resonance effect has been shown in this system in which light enhances the transduction of a weak, periodic mechanosensory (hydrodynamic) stimulus. It is not known, however, whether an optimal response from the CPR is induced by a single sine wave cycle or some other waveform. We have experimentally investigated this favorable waveform by driving a tailfan preparation with mechanical 10 Hz correlated Ornstein-Uhlenbeck noise and calculating the response function from the spike-triggered average of the applied noise waveform. We will discuss differences in the shape of the optimal waveform under dark and light conditions, as well as what seems to be a noticeable difference in the magnitude of the animals' response to a noisy stimulus in comparison with a periodic stimulus.

Clinical features of Haff disease and myositis after the consumption of boiled brackish water crayfish: a retrospective study of 96 cases at a single centre.

Science.gov (United States)

He, Fei; Ni, Jun; Huang, Jun-Ai; Liu, Yao; Wu, Chao; Wang, Jun

2018-05-08

The present study describes the difference in clinical features between the patients with Haff disease and crayfish-related myositis (CRM) after crayfish consumption. This was a single-centre, retrospective analysis at the Emergency Department of the Drum Tower Hospital of Nanjing University School of Medicine from July to August of 2016. The baseline information came from the Electronic Medical Record System at the institution. Totally 96 patients were included, of whom 52 patients were confirmed to have Haff disease and 44 patients were CRM. The illness predominately occurs in summer and most of them (55/96) are female. The primary clinical features are myalgia, muscle allodynia and back and body pain. Statistical differences in the baseline CK, CK-MB, myoglobin, and the WBC count exist between the Haff disease and CRM groups (P < 0.05). The serum levels of CK and CK-MB increase in the second (a median time 29.2 ± 7.4 h) or third day (a median time 54.8 ± 9.3 h) of disease course, and then rapidly decreased to normal levels, while the levels of myoglobin peak at the admission (a median time 7.7 ± 6.4 h) and became normal after admission. There were no fatalities or complications during this study. All 96 patients recovered in a week. Of them, 75 were followed-up within 1 month and none had recurrence. The Haff disease and CRM after boiled crayfish consumption reflect a different severity of muscle injury, and reveal similar clinical characteristics and most of the laboratory values. The overall prognosis of both is good.

Palm Swamp Wetland Ecosystems of the Upper Amazon: Characterizing their Distribution and Inundation State Using Multiple Resolution Microwave Remote Sensing

Science.gov (United States)

Podest, E.; McDonald, K. C.; Schröder, R.; Pinto, N.; Zimmermann, R.; Horna, V.

2011-12-01

Palm swamp wetlands are prevalent in the Amazon basin, including extensive regions in northern Peru. These ecosystems are characterized by constant surface inundation and moderate seasonal water level variation. The combination of constantly saturated soils, giving rise to low oxygen conditions, and warm temperatures year-round can lead to considerable methane release to the atmosphere. Because of the widespread occurrence and expected sensitivity of these ecosystems to climate change, knowledge of their spatial extent and inundation state is crucial for assessing the associated land-atmosphere carbon exchange. Precise spatio-temporal information on palm swamps is difficult to gather because of their remoteness and difficult accessibility. Spaceborne microwave remote sensing is an effective tool for characterizing these ecosystems since it is sensitive to surface water and vegetation structure and allows monitoring large inaccessible areas on a temporal basis regardless of atmospheric conditions or solar illumination. We are developing a remote sensing methodology using multiple resolution microwave remote sensing data to determine palm swamp distribution and inundation state over focus regions in the Amazon basin in northern Peru. For this purpose, two types of multi-temporal microwave data are used: 1) high-resolution (100 m) data from the Advanced Land Observing Satellite (ALOS) Phased Array L-Band Synthetic Aperture Radar (PALSAR) to derive maps of palm swamp extent and inundation from dual-polarization fine-beam and multi-temporal HH-polarized ScanSAR, and 2) coarse resolution (25 km) combined active and passive microwave data from QuikSCAT and AMSR-E to derive inundated area fraction on a weekly basis. We compare information content and accuracy of the coarse resolution products to the PALSAR-based datasets to ensure information harmonization. The synergistic combination of high and low resolution datasets will allow for characterization of palm swamps and

Yeast communities in Sphagnum phyllosphere along the temperature-moisture ecocline in the boreal forest-swamp ecosystem and description of Candida sphagnicola sp. nov.

Science.gov (United States)

Kachalkin, Aleksey V; Yurkov, Andrey M

2012-06-01

The effects of the temperature-moisture factors on the phylloplane yeast communities inhabiting Sphagnum mosses were studied along the transition from a boreal forest to a swamp biotope at the Central Forest State Biosphere Reserve (Tver region, Russia). We tested the hypothesis that microclimatic parameters affect yeast community composition and structure even on a rather small spatial scale. Using a conventional plating technique we isolated and identified by molecular methods a total of 15 species of yeasts. Total yeast counts and species richness values did not depend on environmental factors, although yeast community composition and structure did. On average, Sphagnum in the swamp biotope supported a more evenly structured yeast community. Relative abundance of ascomycetous yeasts was significantly higher on swamp moss. Rhodotorula mucilaginosa dominated in the spruce forest and Cryptococcus magnus was more abundant in the swamp. Our study confirmed the low occurrence of tremellaceous yeasts in the Sphagnum phyllosphere. Of the few isolated ascomycetous yeast and yeast-like species, some were differentiated from hitherto known species in physiological tests and phylogenetic analyses. We describe one of them as Candida sphagnicola and designate KBP Y-3887(T) (=CBS 11774(T) = VKPM Y-3566(T) = MUCL 53590(T)) as the type strain. The new species was registered in MycoBank under MB 563443.

Galling arthropod diversity in adjacent swamp forests and restinga vegetation in Rio Grande do Sul, Brazil.

Science.gov (United States)

Mendonça, Milton De S; Piccardi, Hosana M F; Jahnke, Simone M; Dalbem, Ricardo V

2010-01-01

Galling arthropods create plant structures inside which they find shelter. Factors acting on galler diversity are still being discussed, with this fauna considered more diverse in xeric than mesic environments (higrothermic stress hypothesis, HSH), and also in more plant diverse sites. Here we compare galler abundance (N), equitability (E), species richness (S) and composition between adjacent restinga (xeric) and swamp forests (mesic) in Parque Estadual de Itapeva (29°21' S, 49°45' W), Rio Grande do Sul, southern Brazil. Five trails, two in swamp forest and three in restingas, were sampled four times each (January/December 2005). After an effort of 60h/person, 621 galled plant individuals belonging to 104 gall morphotypes were recorded. This suggests a high galler diversity for the Park, comparable to the richest places known. No differences were found for N, E or S between restingas and swamp forests. However, faunal composition differs significantly between the vegetation types. The dominant (most abundant) species are different in either vegetation type, and are rare or absent on the other vegetation type. Such species composition analysis is still largely ignored for gallers, and stresses the fact that the HSH cannot explain this pattern, since the latter is based on preferences by the ovipositing galler for xeric sites instead of mesic ones. The two habitats differ in microclimate, but species richness, as would be predicted by the HSH, does not differ. This small scale pattern can perhaps be attributed to biogeographic processes on larger scales, as suggested by the resource synchronisation hypothesis.

Supplementation of Carrot (Daucus carrota as Natural Source of Beta-carotene prepared by Several Methods in Feed to Increase Blue Colour of Freshwater Crayfish Red Claw (Cherax quadricarinatus

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Woro H. Satyantini

2012-02-01

Full Text Available Red claw (Cherax quadricarinatus is one kind of freshwater crayfish that can cultured as consumption or ornamental fish commodities.  The colour of body was important character for performance of red claw as ornamental fish commodity.  Red claw with blue body colour is more expensive than brown.  The purpose of  this experiment was to know the influence addition of carrot with several methods in feed on blue colour  of freshwater crayfish red claw and which was the best preparation method to increase blue colour of freshwater crayfish red claw. The experiment used Completely Randomized Design with four treatments: A (control, B (extract, C (juice and D (shreeded of carrot with 45 ppm dose and five time replicates.  Data was analysed with Kruskal-Wallis and continued with Z test. Result of the experiment was showed that addition of carrot as natural source of beta-carotene with several preparation in feed increase significantly (P Keywords: freshwater crayfish, colour of red claw, carrot, beta-carotene   ABSTRAK Red claw (Cherax quadricarinatus adalah salah satu jenis lobster air tawar yang dapat dibudidayakan sebagai komoditas konsumsi maupun hias.  Sebagai komoditas ikan hias, warna tubuh merupakan karakter penting untuk menunjang penampilan red claw.  Red claw ukuran konsumsi yang memiliki warna biru akan memiliki nilai jual yang lebih tinggi daripada red claw berwarna coklat.  Tujuan penelitian ini untuk mengetahui pengaruh penambahan wortel sebagai sumber beta karoten alami dengan beberapa metoda pengolahan pada pakan terhadap peningkatan warna biru lobster red claw. Penelitian menggunakan Rancangan Acak Lengkap dengan 4 perlakuan : A (kontrol, B (ekstrak, C (jus dan D (serutan wortel dengan menggunakan dosis 45 ppm beta karoten dan ulangan 5 kali.  Data dianalisis dengan uji Kruskal-Wallis dan dilanjutkan dengan uji Z.  Hasil penelitian menunjukkan bahwa penambahan wortel sebagai sumber beta karoten alami dengan beberapa metode

Nitrogen Dynamics Along a Headwater Stream Draining a Fen, Swamp, and Marsh in a Fractured Dolomite Watershed

Science.gov (United States)

Duval, T. P.; Waddington, J. M.

2009-05-01

Stream-wetland interaction has been shown to have a significant effect on nutrient cycling and downstream water quality. Additionally, connection to regional groundwater systems can dilute or enrich stream water with a number of dissolved constituents. This study demonstrates the resultant downstream change in dissolved nitrogen species as a hardwater stream emerges from a calcareous aquifer and traverses a calcareous fen, a cedar swamp, and a cattail marsh over two growing seasons, a very dry 2006 and a very wet 2007. Upon emergence at a number of groundwater seeps, the water contained appreciable nitrate levels averaging 2.72±0.42 mg NO3-N L-1, minimal organic nitrogen, and ammonium below detectable levels. Through the gently sloping calcareous fen, with a stream residence time of ~ 5 hours, NO3-N concentration decreases of 0.35 mg L-1 were observed. Concomitantly, stream recharge into the dolomite bedrock depressed stream discharge values significantly, further removing nitrate from the stream system. This resulted in the fen-bedrock system acting as an estimated net sink of 432 kg of NO3-N in the early summer of 2007, for example. In contrast, the hydrological-biogeochemical systems became decoupled through the swamp during the same period, where concentrations increased from 2.58±0.34 mg L-1 entering the swamp to 2.65±0.58 mg L-1 exiting, but streamflow decreased in general by 5 L s- 1. This resulted in the swamp, with its large depression storage, acting as a small net sink of nitrate (75 kg through the early summer), which would not be detected simply from concentration changes. The concentration-discharge relation realigned through the marsh, where significant groundwater entered the wetland, increasing both concentration and discharge, yielding a small export of 93 kg over the same time period. A series of tracer injections in each wetland type will be presented to compare the streamflow- concentration patterns with the measured nutrient spiralling

Polyancora globosa gen. sp. nov., an aeroaquatic fungus from Malaysian peat swamp forests.

Science.gov (United States)

Voglmayr, Hermann; Yule, Catherine M

2006-10-01

During an investigation of submerged leaves and twigs sampled from tropical peat swamp forests located in Peninsular Malaysia, an anamorphic fungus not attributable to a described genus was detected and isolated in pure culture. Conidial ontogeny was thoroughly studied and illustrated using both light and SEM, which revealed a unique conidial morphology. Analysis of partial nuLSU rDNA and ITS data revealed a phylogenetic position within the Xylariales (Ascomycota), but family affiliation remained unclear.

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

Science.gov (United States)

Wedeux, B. M. M.; Coomes, D. A.

2015-11-01

Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplay between environmental factors and disturbance legacies on forest canopy structure across landscapes is practically unexplored. We used airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistent with previous work linking deep peat to stunted tree growth. Gap size frequency distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of Pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and illegal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced. With logging, the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and peat depth gradient within the old-growth tropical peat swamp forest. This relationship breaks down after selective logging, with canopy structural recovery, as observed by ALS, modulated by environmental conditions. These findings improve our

Dissolved Oxygen Dynamics in Backwaters of North America's Largest River Swamp

Science.gov (United States)

Bueche, S. M.; Xu, Y. J.; Reiman, J. H.

2017-12-01

The Atchafalaya River (AR) is the largest distributary of the Mississippi River flowing through south-central Louisiana, creating North America's largest river swamp basin - the Atchafalaya River Basin (ARB). Prior to human settlement, the AR's main channel was highly connected to this large wetland ecosystem. However, due to constructed levee systems and other human modifications, much of the ARB is now hydrologically disconnected from the AR's main channel except during high flow events. This lack of regular inputs of fresh, oxygenated water to these wetlands, paired with high levels of organic matter decomposition in wetlands, has caused low oxygen-deprived hypoxic conditions in the ARB's back waters. In addition, due to the incredibly nutrient-rich and warm nature of the ARB, microbial decomposition in backwater areas with limited flow often results in potentially stressful, if not lethal, levels of DO for organisms during and after flood pulses. This study aims to investigate dynamics of dissolved oxygen in backwaters of the Atchafalaya River Basin, intending to answer a crucial question about hydrological and water quality connectivity between the river's mainstem and its floodplain. Specifically, the study will 1) conduct field water quality measurements, 2) collect composite water samples for chemical analysis of nutrients and carbon, 3) investigate DO dynamics over different seasons for one year, and 4) determine the major factors that affect DO dynamics in this unique swamp ecosystem. The study is currently underway; therefore, in this presentation we will share the major findings gained in the past several months and discuss backwater effects on river chemistry.

Calcium transport mechanism in molting crayfish revealed by microanalysis

International Nuclear Information System (INIS)

Mizuhira, V.; Ueno, M.

1983-01-01

Crayfish provide a good model in which to study the transport mechanism of Ca ions. During the molting stage, decalcified Ca ions are transferred into the blood and accumulate in the gastrolith epithelium, after which a gastrolith is formed on the surface of the epithelium. The gastrolith is dissolved in the stomach after molting, and the Ca is reabsorbed and redistributed throughout the newly formed exoskeleton. We studied the mechanism of Ca transport by cytochemical precipitation of Ca ions and by electron microanalysis, including X-ray microanalysis (EDX) and electron energy-loss spectroscopy (EELS), with a computer. In EDX analysis, the fine precipitates of K-antimonate in the gastrolith mitochondria clearly defined Ca with antimony; we also observed a large amount of Ca-oxalate in the mitochondria, and Ca-K X-ray pulses were clearly defined. Ca-K X-rays were also detected from fresh freeze-substituted mitochondria. Finally, we succeeded in taking a Ca-L EELS image from the mitochondria of fresh freeze-substituted thin sections. Only a very small amount of Ca was detected from the cell membrane and other organelles. Ca-adenosine triphosphatase (ATPase) and Mg-ATPase activity was also very clearly demonstrated in the mitochondria. These enzymes may play an important role in Ca metabolism

Isolation of crustecdysone (20R-hydroxyecdysone) from a crayfish (Jasus lalandei H. Milne-Edwards)

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Horn, D. H. S.; Fabbri, S.; Hampshire, F.; Lowe, M. E.

1968-01-01

1. A small amount (2mg.) of crustecdysone, a moulting hormone of crustaceans, was isolated from 1 ton of crayfish waste. 2. The purification procedure used was developed with the aid of crustacean and insect bioassays. 3. CM-Sephadex was found to be superior to Sephadex and very effective for the chromatographic separation of crustecdysone from other non-ionic compounds. The higher efficiency of CM-Sephadex is attributed to the greater number of carboxyl groups available for hydrogen-bonding. 4. Reversed-phase chromatography, with butan-1-ol–cyclohexane mixtures as the stationary phase and water as the flowing phase, proved superior to countercurrent distribution with these solvents for the fractionation of purified extracts. 5. A second moulting hormone, deoxycrustecdysone, and the red-concentrating hormone were obtained in a partially purified form. PMID:5685865

Field and laboratory tests on acute toxicity of cadmium to freshwater crayfish

Energy Technology Data Exchange (ETDEWEB)

1986-09-01

Environmental regulatory standards for cadmium (EPA 1980), like those for most pollutants, are based on acute, laboratory toxicity tests of single species. Such tests can be conducted rapidly and inexpensively in comparison to acute or chronic field studies, but their validity has often been questioned. Laboratory-based criteria are subject to two criticisms: (1) chemical and physical conditions differ greatly in degree and variability from laboratory to field, and (2) species are not isolated, but live in an ecosystem of interacting taxa and biofeedback. To investigate the validity of basing field toxicity standards on laboratory data, the authors subjected the freshwater crayfish Orconectes immunis for 96 h to various levels of cadmium in laboratory aquaria and experimental ponds. The study was designed to evaluate in part the first criticism of lab-based criteria. The studies were conducted concurrently with similar short-term experiments on the fathead minnow, Pimephales promelas, and coincided with studies of chronic cadmium stress on fathead minnows in experimental ponds.

[Distribution, surface and protected area of palm-swamps in Costa Rica and Nicaragua].

Science.gov (United States)

Serrano-Sandí, Juan; Bonilla-Murillo, Fabian; Sasa, Mahmood

2013-09-01

In Central America, palm swamps are known collectively as yolillales. These wetlands are usually dominated by the raffia palm Raphia taedigera, but also by the royal palm Manicaria saccifera and -in lower extensions- by the American oil palm Elaeis oleifera. The yolillales tend to be poor in woody species and are characteristic of regions with high rainfall and extensive hydroperiods, so they remain flooded most of the year. The dominance of large raffia palm leaves in the canopy, allow these environments to be distinguishable in aerial photographs, which consequently has helped to map them along most of their distribution. However, while maps depicting yolillales are available, the extent of their surface area, perimeter and connectivity remains poorly understood. This is particularly true for yolillales in Costa Rica and Nicaragua, countries that share a good proportion of palm dominated swaps in the Rio San Juan Basin. In addition, it is not known the actual area of these environments that is under any category of protection according to the conservation systems of both countries. As a first step to catalog yolillal wetlands in Costa Rica and Nicaragua, this paper evaluates cartographic maps to delineate yolillales in the region. A subsample of yolillales mapped in this study were visited and we geo-referenced them and evaluate the extent and condition of the swamp. A total of 110 883.2ha are classified as yolillales in Nicaragua, equivalent to 22% of wetland surface area recorded for that country (excluding the Cocibolca and Xolothn Lakes). In Costa Rica, 53 931.3ha are covered by these palm dominated swamps, which represent 16.24% of the total surface area covered by wetlands. About 47% of the area covered by yolillales in Nicaragua is under some category of protection, the largest extensions protected by Cerro Silva, Laguna Tale Sulumas and Indio Maiz Nature Reserves. In Costa Rica, 55.5% of the area covered by yolillal is located within protected areas

Seed germination studies on Gymnacranthera canarica (King Warb. - a Vulnerable tree species of a highly threatened Myristica swamp ecosystem

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K. Keshavachandra

2016-07-01

Full Text Available Gymnacranthera canarica (King Warb. is an exclusive Myristica swamp species endemic to the Western Ghats.  The Myristica swamp is a Critically Endangered ecosystem.  Studies were carried out to assess the viability, germination and storage behaviour of Gymnacranthera canarica seeds.  In the present study, it was observed that seeds have shown an initiation of germination after two weeks.  A maximum of 90% germination was recorded when the initial moisture content was 38.04 ± 1.75 %.  A decreased percentage (3% was observed when the moisture content reached 14.26 ± 2.3 after 70 days of storage.  Seeds failed to germinate beyond this moisture level.  A desiccation study showed recalcitrant behaviour and seeds can be stored in lab conditions for up to two and half months.

Old carbon efflux from tropical peat swamp drainage waters

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Vihermaa, Leena; Waldron, Susan; Evers, Stephanie; Garnett, Mark; Newton, Jason

2014-05-01

Tropical peatlands constitute ~12% of the global peatland carbon pool, and of this 10% is in Malaysia1. Due to rising demand for food and biofuels, large areas of peat swamp forest ecosystems have been converted to plantation in Southeast Asia and are being subjected to degradation, drainage and fire, changing their carbon fluxes eg.2,3. Dissolved organic carbon (DOC) lost from disturbed tropical peat can be derived from deep within the peat column and be aged from centuries to millennia4 contributing to aquatic release and cycling of old carbon. Here we present the results of a field campaign to the Raja Musa Peat Swamp Forest Reserve in N. Selangor Malaysia, which has been selectively logged for 80 years before being granted timber reserve status. We measured CO2 and CH4efflux rates from drainage systems with different treatment history, and radiocarbon dated the evasion CO2 and associated [DOC]. We also collected water chemistry and stable isotope data from the sites. During our sampling in the dry season CO2 efflux rates ranged from 0.8 - 13.6 μmol m-2 s-1. Sediments in the channel bottom contained CH4 that appeared to be primarily lost by ebullition, leading to sporadic CH4 efflux. However, dissolved CH4 was also observed in water samples collected from these systems. The CO2 efflux was aged up to 582±37 years BP (0 BP = AD 1950) with the associated DOC aged 495±35 years BP. Both DOC and evasion CO2 were most 14C-enriched (i.e. younger) at the least disturbed site, and implied a substantial component of recently fixed carbon. In contrast, CO2 and DOC from the other sites had older 14C ages, indicating disturbance as the trigger for the loss of old carbon. 1Page et al., 2010 2Hooijer et al., 2010 3Kimberly et al., 2012 4Moore et al., 2013

Gnathostoma spinigerum in live Asian swamp eels (Monopterus spp.) from food markets and wild populations, United States

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Cole, Rebecca A.; Choudhury, Anindo; Nico, Leo G.; Griffin, Kathryn M.

2014-01-01

In Southeast Asia, swamp eels (Synbranchidae: Monopterus spp.) are a common source of human gnathostomiasis, a foodborne zoonosis caused by advanced third-stage larvae (AL3) of Gnathostoma spp. nematodes. Live Asian swamp eels are imported to US ethnic food markets, and wild populations exist in several states. To determine whether these eels are infected, we examined 47 eels from markets and 67 wild-caught specimens. Nematodes were identified by morphologic features and ribosomal intergenic transcribed spacer–2 gene sequencing. Thirteen (27.7%) M. cuchia eels from markets were infected with 36 live G. spinigerum AL3: 21 (58.3%) in liver; 7 (19.4%) in muscle; 5 (13.8%) in gastrointestinal tract, and 3 (8.3%) in kidneys. Three (4.5%) wild-caught M. albus eels were infected with 5 G. turgidum AL3 in muscle, and 1 G. lamothei AL3 was found in a kidney (both North American spp.). Imported live eels are a potential source of human gnathostomiasis in the United States.

Weeds optimally grow in peat swamp after burning

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P.D. Susanti

2014-07-01

Full Text Available After clearing land by burning the peat, then the weeds and undergrowth will flourish. Even sometimes, the weeds are eventually burned again. Weed is known as a destroyer plant that has to be controlled. Through proper treatment, the existing weeds in peatlands can be potentiallly exploited. The purpose of this study was to determine the calorific value of briquettes as one of peatland weeds utilization. The results showed that the calorific value ranged from 2,492 cal/g to 5,230 cal/g. The lowest calorific value was on ‘teki kecil’ grass (Scirpus grossus Lf, while the highest calorific value was observed for ‘bantalaki grass’ (Hymenachne amplexicaulis Nees. The high calorific value of the peat weeds are potential for biomass briquettes raw materials. The utilization and use of peat weed briquettes as a raw materials expected can reduce land degradation due to peat swamp burning

Identifying food deserts and swamps based on relative healthy food access: a spatio-temporal Bayesian approach.

Science.gov (United States)

Luan, Hui; Law, Jane; Quick, Matthew

2015-12-30

Obesity and other adverse health outcomes are influenced by individual- and neighbourhood-scale risk factors, including the food environment. At the small-area scale, past research has analysed spatial patterns of food environments for one time period, overlooking how food environments change over time. Further, past research has infrequently analysed relative healthy food access (RHFA), a measure that is more representative of food purchasing and consumption behaviours than absolute outlet density. This research applies a Bayesian hierarchical model to analyse the spatio-temporal patterns of RHFA in the Region of Waterloo, Canada, from 2011 to 2014 at the small-area level. RHFA is calculated as the proportion of healthy food outlets (healthy outlets/healthy + unhealthy outlets) within 4-km from each small-area. This model measures spatial autocorrelation of RHFA, temporal trend of RHFA for the study region, and spatio-temporal trends of RHFA for small-areas. For the study region, a significant decreasing trend in RHFA is observed (-0.024), suggesting that food swamps have become more prevalent during the study period. For small-areas, significant decreasing temporal trends in RHFA were observed for all small-areas. Specific small-areas located in south Waterloo, north Kitchener, and southeast Cambridge exhibited the steepest decreasing spatio-temporal trends and are classified as spatio-temporal food swamps. This research demonstrates a Bayesian spatio-temporal modelling approach to analyse RHFA at the small-area scale. Results suggest that food swamps are more prevalent than food deserts in the Region of Waterloo. Analysing spatio-temporal trends of RHFA improves understanding of local food environment, highlighting specific small-areas where policies should be targeted to increase RHFA and reduce risk factors of adverse health outcomes such as obesity.

Ornithological aspects on the swamp Herghelie – Mangalia (Romania

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GACHE Carmen

2005-09-01

Full Text Available This ornithological notice present information on the avifauna recorded in the swamp Herghelie – Mangalia beginning with the 1998’s summer. We identified 132 species of birds. The reedbeds cover about 35% of the swamp’s surface, offering good conditions for the breeding season (Ixobrychus minutus, Botaurus stellaris, Cygnus olor, Himantopus himantopus, Recurvirostra avosetta and Sterna hirundo but also for migration period. The breeding population is low due the high level of the human pressure. Due the presence of sulphurous sources and peat bed, the water is not freezing during the winter, transforming this territory in an important wintering site in the southeastern Dobroudja. Interesting is also the presence in this area during the winter of some summer visitors’ species for Romania like: Phalacrocorax pygmeus, Botaurus stellaris and Rallus aquaticus.

Modeling Flood Plain Hydrology and Forest Productivity of Congaree Swamp, South Carolina

Science.gov (United States)

Doyle, Thomas W.

2009-01-01

An ecological field and modeling study was conducted to examine the flood relations of backswamp forests and park trails of the flood plain portion of Congaree National Park, S.C. Continuous water level gages were distributed across the length and width of the flood plain portion - referred to as 'Congaree Swamp' - to facilitate understanding of the lag and peak flood coupling with stage of the Congaree River. A severe and prolonged drought at study start in 2001 extended into late 2002 before backswamp zones circulated floodwaters. Water levels were monitored at 10 gaging stations over a 4-year period from 2002 to 2006. Historical water level stage and discharge data from the Congaree River were digitized from published sources and U.S. Geological Survey (USGS) archives to obtain long-term daily averages for an upstream gage at Columbia, S.C., dating back to 1892. Elevation of ground surface was surveyed for all park trails, water level gages, and additional circuits of roads and boundaries. Rectified elevation data were interpolated into a digital elevation model of the park trail system. Regression models were applied to establish time lags and stage relations between gages at Columbia, S.C., and gages in the upper, middle, and lower reaches of the river and backswamp within the park. Flood relations among backswamp gages exhibited different retention and recession behavior between flood plain reaches with greater hydroperiod in the lower reach than those in the upper and middle reaches of the Congaree Swamp. A flood plain inundation model was developed from gage relations to predict critical river stages and potential inundation of hiking trails on a real-time basis and to forecast the 24-hour flood In addition, tree-ring analysis was used to evaluate the effects of flood events and flooding history on forest resources at Congaree National Park. Tree cores were collected from populations of loblolly pine (Pinus taeda), baldcypress (Taxodium distichum), water

Differences in impacts of Hurricane Sandy on freshwater swamps on the Delmarva Peninsula, Mid−Atlantic Coast, USA

Science.gov (United States)

Middleton, Beth A.

2016-01-01

Hurricane wind and surge may have different influences on the subsequent composition of forests. During Hurricane Sandy, while damaging winds were highest near landfall in New Jersey, inundation occurred along the entire eastern seaboard from Georgia to Maine. In this study, a comparison of damage from salinity intrusion vs. wind/surge was recorded in swamps of the Delmarva Peninsula along the Pocomoke (MD) and Nanticoke (DE) Rivers, south of the most intense wind damage. Hickory Point Cypress Swamp (Hickory) was closest to the Chesapeake Bay and may have been subjected to a salinity surge as evidenced by elevated salinity levels at a gage upstream of this swamp (storm salinity = 13.1 ppt at Nassawango Creek, Snow Hill, Maryland). After Hurricane Sandy, 8% of the standing trees died at Hickory including Acer rubrum, Amelanchier laevis, Ilex spp., and Taxodium distichum. In Plot 2 of Hickory, 25% of the standing trees were dead, and soil salinity levels were the highest recorded in the study. The most important variables related to structural tree damage were soil salinity and proximity to the Atlantic coast as based on Stepwise Regression and NMDS procedures. Wind damage was mostly restricted to broken branches although tipped−up trees were found at Hickory, Whiton and Porter (species: Liquidamabar styraciflua, Pinus taeda, Populus deltoides, Quercus pagoda and Ilex spp.). These trees fell mostly in an east or east−southeast direction (88o−107o) in keeping with the wind direction of Hurricane Sandy on the Delmarva Peninsula. Coastal restoration and management can be informed by the specific differences in hurricane damage to vegetation by salt versus wind.

Prevalence and intensity of third stage Gnathostoma spinigerum larvae in swamp eels sold in three large markets in Bangkok, Thailand.

Science.gov (United States)

Saksirisampant, Wilai; Nuchprayoon, Surang; Wiwanitkit, Viroj; Kraivichian, Kanyarat; Suwansaksri, Jamsai

2002-01-01

Gnathostoma spinigerum is a common human tissue parasite in Thailand. The swamp eel is the major intermediate or paratenic host for this parasite. The high prevalence of the infective third stage larvae (L3) of this parasite in the rainy season has been noted in previous studies. During June 1999 (rainy season), we performed a cross-sectional survey of the prevalence and the intensity of G. spinigerum L3s in the livers of swamp eels that were obtained from three large Bangkok markets (Klong Toey, Pran Nok, and Tevej). Of a total of 785 livers, G. spinigerum L3s were found in 97: an infection rate of 12%. The prevalence rates in Klong Toey, Pran Nok, and Tevej markets were 13%, 10% and 14% respectively. There was no significant difference in the proportion of infected eels between the markets (p > 0.05). The intensity of L3 burden in the livers ranged from 1-17 larvae, with an average of 2.60 +/- 0.24 larvae (mean +/- SE). In this study a high prevalence of G. spinigerum L3s was found; there was no significant difference in the intensity of larvae in swamp eels between markets. These findings emphasize the importance of public health education: people need to be aware of the dangers of consuming raw or undercooked food.

Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

Science.gov (United States)

Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

2008-01-01

How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

CONSIDERATIONS ON THE ANTHROPIC IMPACT IN THE AREA OF THE ORNITHOLOGIC RESERVATION “THE SWAMPS FROM SATCHINEZ” (TIMIŞ COUNTY

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Rodica Török-Oance

2005-01-01

Full Text Available The estimate of the anthropic impact within the Ornithologic Reservation Swamps from Satchinez is based on the field notes in the period 2003-2005, the air photos taken in 2004 and the reconstitution of past situations (1963-1973 using the photoplans from that period. Within the reservation and the buffer area a series of anthropic activities are taking place, allowed or not, which have a negative impact on the protected area: agricultural works (including agro-chemical treatments, grazing, mowing, hydrotechnical arrangements, illegal tree felling, cutting and burning the reed, poaching, hunting and fishing, collecting biological material, transport, tourism and petrol exploitation. All these lead to the deterioration of the habitat, affect the life of the birds, the water, the clogging of the swamp and cause the disappearance of the clean water spots thus endangering the reservation itself.

Effects of both ecdysone and the acclimation to low temperature, on growth and metabolic rate of juvenile freshwater crayfish Cherax quadricarinatus (Decapoda, Parastacidae

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Anouk Chaulet

2013-06-01

Full Text Available Growth, metabolic rate, and energy reserves of Cherax quadricarinatus (von Martens, 1868 juveniles were evaluated in crayfish acclimated for 16 weeks to either 25ºC (temperature near optimum or 20ºC (marginal for the species. Additionally, the modulating effect of ecdsyone on acclimation was studied. After 12 weeks of exposure, weight gain of both experimental groups acclimated to 25ºC (control: C25, and ecdysone treated: E25 was significantly higher than that of those groups acclimated to 20ºC (C20 and E20. A total compensation in metabolic rate was seen after acclimation from 25ºC to 20ºC; for both the control group and the group treated with ecdysone. A Q10value significantly higher was only observed in the group acclimated to 20ºC and treated with ecdysone. A reduction of glycogen reserves in both hepatopancreas and muscle, as well as a lower protein content in muscle, was seen in both groups acclimated to 20ºC. Correspondingly, glycemia was always higher in these groups. Increased lipid levels were seen in the hepatopancreas of animals acclimated to 20ºC, while a higher lipid level was also observed in muscle at 20ºC, but only in ecdysone-treated crayfish.

POTENCY OF RAMIN (Gonystylus bancanus Kurtz. AND OTHER COMMERCIAL SPECIES IN PEAT SWAMP FOREST MANAGED WITH TPTI SILVICULTURAL SYSTEM IN BAGAN, RIAU

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Hendromono Hendromono

2005-07-01

Full Text Available Ramin  (Gonystylus bancanus Kurtz.  is one  of  the  tree  species in  peat-swamp  forest  that  is endangered due to excessive exploitation. The objective of this research was to assess the potency of rarnin and other commercial tree species in primary and logged over peat-swamp forests at Bagan, Riau. The tree stands were inventoried in primary forest of the 2004 and 2006 Annual Work Plan (RKTs and in  the  1997  and  2001  RKTs  managed  with  Indonesian  Selective Cutting  and  Planting  (TPTI silvicultural system.  The  result  showed  that  rarnin in  Bagan peat-swamp  forest  was not  evenly distributed. The total number of ramin  in tree stage in primary forests was fewer than that in  logged over forests.  The total number of ramin species at tree stage in primary forest was between 4.5  and 5 trees ha·' with the important value index (IVI of 10.3  to 12.0%,  whereas the one at logged over forest were between 2.5 and 15  trees ha·' with theM    indices of 7.9 to 20.4%.  Commercial species of swamp meranti (Shorea uliginosaand S. teysmaniana and balam/ suntai or (Palaqqiumspp. were dominant at tree stage both in the primary and the logged over forests. Enrichment in logged over forests is not needed since the total number of seedlings and saplings  is enough. The total number of potential core trees in logged over forests was enough for the next cutting cycle. The effort that must be done in logged over forests is to protect them from illegal logging.

Effect of different concentration of fish oil in skim milk-egg yolk extenders on post- thawed semen qualities of Kalang swamp buffalo bull

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Abdul Malik

2018-01-01

Full Text Available Objective: To explore the effect of fish oil at different concentrations on post-thawed semen of Kalang swamp buffalo. Methods: A total of 4 Kalang swamp buffalo bulls with 3-5 years of age and weighed about 340-360 kg were slected. Semen was regularly collected from these buffalo bulls once a week by an artificial vagina. Fish oil was supplementary at the dosages of 0 mg (control, 50 mg, 100 mg, 150 mg, and 200 mg to the extender (skim milk-egg yolk. Fresh, pre-freezing and frozen semen were thawed at 37 °C and evaluated for motility, viability, morphology, and plasma integrity of membrane. Results: The study results indicated that before freezing, supplementation of fish oil at the dose of 150 mg in the extender had significantly motility. And a significant (P<0.05 increase was observed in viability and motility of post-thawed semen at the dose of 150 mg fish oil, which was in difference with other treatment groups. Conclusions: Addition of 150 mg fish oil in the extender could be positive for the enhancement of the quality of post-thawed semen of Kalang swamp buffaloes.

TALL HERB SPRUCE FORESTS AS CLIMAX COMMUNITIES ON LOWLAND SWAMPS OF BRYANSK POLESIE

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O. I. Evstigneev

2017-09-01

Full Text Available Nettle grey alder forests are a dominant forest type on lowland swamps in the Bryansk Polesie. They are formed as a result of repeated cuttings in the place of tall herb spruce forests. Tall herb spruce forests are very rare communities in the vegetation cover in this area due to clear cutting, melioration and peat extraction. An assessment of the succession status of tall herb spruce forests and nettle grey alder forests was carried out in this paper. The criteria of climax state and succession state of communities, developed for Eastern European forests, were used. These criteria are based on the degree of intensity of the following signs in the community: 1 the completeness of species composition of tree synusia; 2 the ontogenetic structure of tree species cenopopulation; 3 the gap-mosaic stand structure; 4 the diversity of microsites in soil cover; 5 the completeness of species composition and ecological-coenotic diversity of vascular species. We showed that tall herb spruce forest, as opposed to black alder forest, is close to communities of the climax type. This is evidenced by the following features of cenosis: firstly, all tree species in the area that covers the Bryansk Polesie and that are able to grow on lowland swamps are represented in the spruce forest (Alnus glutinosa, Betula pubescens, Fraxinus excelsior, Padus avium, Picea abies, Salix pentandra, Sorbus aucuparia, Ulmus glabra. Secondly, a steady turnover of generations is carried out in the cenopopulations of main edificators (Picea abies and Alnus glutinosa. This is evidenced by the complete and left-sided structure of their ontogenetic spectrum. Thirdly, a system of asynchronously developing gaps (parcels, which are formed on the site of old tree falls, is formed in the community. This ensures the continuous renewal of spruce and alder populations and creates conditions for the regeneration of other tree species. Fourthly, the structure of biogenic microsites has been formed

Studies on algea of Da′erbin lake and its surrounding swamps in daxing anling mountain

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LI Xiaofei

2012-08-01

Full Text Available The paper reports 234 taxa of algae (excluding diatomas and desmids in Da′erbin Lake and its surrounding swamps in the Great Xing′an Mountains.They were identified belong to 6 phylums 79 generas 197 species 31 varieties and 6 forms.Among them Characium ornithocephalum var.pringsheimii (A.Br. Kom.,Characium pluricoccum Kor.,Quadrigula korsikovii Kom.,Crucigeniella rectangularis (Ng. Kom.are newly reported in China.

From Blood to Brain: Adult-Born Neurons in the Crayfish Brain Are the Progeny of Cells Generated by the Immune System

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Barbara S. Beltz

2017-12-01

Full Text Available New neurons continue to be born and integrated into the brains of adult decapod crustaceans. Evidence in crayfish indicates that the 1st-generation neural precursors that generate these adult-born neurons originate in the immune system and travel to the neurogenic niche via the circulatory system. These precursors are attracted to the niche, become integrated amongst niche cells, and undergo mitosis within a few days; both daughters of this division migrate away from the niche toward the brain clusters where they will divide again and differentiate into neurons. In the crustacean brain, the rate of neuronal production is highly sensitive to serotonin (5-hydroxytryptamine, 5-HT levels. These effects are lineage-dependent, as serotonin's influence is limited to late 2nd-generation neural precursors and their progeny. Experiments indicate that serotonin regulates adult neurogenesis in the crustacean brain by multiple mechanisms: via direct effects of serotonin released from brain neurons into the hemolymph or by local release onto target cells, or by indirect influences via a serotonin-mediated release of agents from other regions, such as hormones from the sinus gland and cytokines from hematopoietic tissues. Evidence in crayfish also indicates that serotonin mediates the attraction of neural precursors generated by the immune system to the neurogenic niche. Thus, studies in the crustacean brain have revealed multiple roles for this monoamine in adult neurogenesis, and identified several pathways by which serotonin influences the generation of new neurons.

Carcass Characteristics and Meat Quality of Swamp Buffaloes (Bubalus bubalis) Fattened at Different Feeding Intensities.

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Lambertz, C; Panprasert, P; Holtz, W; Moors, E; Jaturasitha, S; Wicke, M; Gauly, M

2014-04-01

Twenty-four male 1-year old swamp buffaloes (Bubalus bubalis) were randomly allocated to 4 groups. One group grazed on guinea grass (GG) and another on guinea grass and the legume Stylosanthes guianensis (GL). The other two groups were kept in pens and fed freshly cut guinea grass and concentrate at an amount of 1.5% (GC1.5) and 2.0% (GC2.0) of body weight, respectively. The effect of the different feeding intensities on carcass characteristics and meat quality were assessed. The mean body weight at slaughter was 398 (±16) kg. Average daily gain was higher in concentrate-supplemented groups (570 and 540 g/d in GC1.5 and GC2.0, respectively) when compared to GG (316 g/d) and GL (354 g/d) (pbuffaloes. Results of the present study showed that the supplementation of pasture with concentrate enhances the growth and carcass characteristics of swamp buffaloes expressed in superior dressing percentage, better muscling, and redder meat with a higher content of protein and fat, whereas animals grazing only on pasture had a more favorable fatty acid profile and water holding capacity. In conclusion, the supplementation of concentrate at a rate of about 1.5% of body weight is recommended to improve the performance and carcass quality of buffaloes.

STRUCTURE OF NATURAL REGENERATION IN RELATION TO SOIL PROPERTIES AND DISTURBANCE IN TWO SWAMP FORESTS

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Marly Antonielle Ávila

2016-03-01

Full Text Available Veredas (palm swamps is a type of vegetation associated with watercourses, characterized by the presence of Mauritia flexuosa palm trees. These systems are not well understood and suffer from high anthropogenic pressure. The aims of this study were to describe the natural regeneration of two swamp forests in vereda systems with different anthropogenic impacts and investigate if the variation in these plant communities are associated to edaphic conditions. The study was performed in preserved and impacted sites located in the Environmental Protection Area of the Pandeiros River in northern Minas Gerais. At each site, one hundred 25 m2 plots were established for surveying regenerating shrubs and trees (≥1 cm diameter at the base of the stem and < 3 cm diameter at breast height. Vegetation structure was evaluated by phytosociological parameters, similarity index, and size distribution of individuals. Regenerating strata was correlated with chemical and physical soil analyses. The vegetation at the preserved site was characterized by a higher number of individuals and a lower diversity but contained species that were typical of flooded areas. The results also showed differences in soil nutrient availability between sites that influenced the distribution of species at the two study sites.

Stable carbon isotope composition of organic material and carbonate in sediment of a swamp and lakes in Honshu island, Japan

International Nuclear Information System (INIS)

Ishizuka, Toshio

1978-01-01

Recent sediments from a swamp and lakes in Honshu were analyzed for organic carbon and carbonate contents, and stable isotope ratios of carbon in the organic materials and carbonate. delta C 13 values of the carbonate tend to be distinctly larger than those of organic carbon in reducing condition as natural gas field, whereas in oxidizing SO 4 -reducing conditions, they are slightly larger than those of organic carbon within the limited range of a few per mil. Carbon isotopic compositions of organic carbon in sediment of the swamp, Obuchi-numa, were analyzed and compared with habitat analysis of associated fossil diatoms. deltaC 13 values of organic carbon in the sediment vary in correlation with the species abundance in habitat of the associated fossil diatoms, ranging from fresh-water (-0.0282) to coastal marine (-0.0236) via brackish. (auth.)

Toxicity induced by dieldrin and chlorpyrifos in the freshwater crayfish Cambarellus montezumae (Cambaridae

Directory of Open Access Journals (Sweden)

Sandra Díaz-Barriga Arceo

2015-03-01

Full Text Available The toxicity induced by insecticides in aquatic organisms is of utmost relevance because it may give a clue about the degree of health or damage of the involved ecosystem. In the present report, we determined the effect of dieldrin (DD and chlorpyrifos (CP on the freshwater crayfish, Cambarellus montezumae. The organisms (4-6cm in diameter were collected in the Ignacio Ramírez Reservoir, situated at 50km Northeast of Mexico City, in the Rio Lerma Basin. Initially, we determined the LC50 value with the Probit method, then the DNA damage with single cell gel electrophoresis (comet assay applied at 24, 48, and 72h of exposure to the brain and hepatopancreas of animals exposed (in reconstituted water to 0.05 and 0.5µg/L of each insecticide. In the hepatopancreas of the same organisms, we determined the lipid peroxidation by applying the TBARS test. DNA damage and lipid peroxidation were also evaluated with the same methods to organisms exposed in water from the reservoir. In regard to the LC50 at 72h of exposure, we found a value of 5.1µg/L and a value of 5.62µg/L for DD and CP, respectively. The comet assay applied at different exposure times showed significant DNA damage to both organs, with respect to the control level. In the case of DD, statistical significance was observed for the two doses in the whole evaluated schedule. CP was genotoxic in the brain with the high dose at 72h, and in the hepatopancreas with the two tested doses at all evaluated exposure times. Also, a significant lipid peroxidation increase was detected with the two doses of insecticides. In the study with water from the reservoir, a more pronounced DNA damage was detected. Our results showed strong DNA damage induced by both insecticides in the crayfish, as well as a correlation with the lipid peroxidation effect, suggesting that oxidative stress is involved in the genotoxic alteration. Our results also showed the usefulness of the studied organism as well as the

Improvement of the productivity of the swamp buffalo of S.E. Asia

International Nuclear Information System (INIS)

Frisch, J.E.; Vercoe, J.E.

1984-01-01

The needs of an expanding human population necessitate an increase in numbers and efficiency of output if the swamp buffalo is to remain as a significant component of S.E. Asian agriculture. Biological constraints to an increase in numbers are associated mainly with high calf mortality and low reproductive rate. A combination of vaccination and deworming markedly increases calf survival and provides the simplest means for increasing buffalo numbers. However, methods for improvement of the low inherent fertility of buffaloes remain to be devised. A first step towards a genetic solution is to obtain accurate comparative data for reproductive rates of different buffalo breeds and measures of the magnitude of heterosis for reproductive rate. However, facilities to do this in the near future do not exist. Milk yield or draft power could be most rapidly increased by crossing to river breeds with the optimum proportion of river breed in the cross determined by that level of milk yield and size commensurate with the locally available feed. This is the only method currently available that allows genetic improvement to initially equal or exceed the rate of human population growth. The lack of both large, well-documented herds and efficient AI schemes at present rules against within-breed selection as a method of improvement for any productive trait. It is unrealistic to expect large amounts of high-quality feeds to ever become available for rearing swamp buffaloes and there is a need to develop the facilities and expertise to allow comparative evaluation of buffalo breeds, the exploitation of heterosis in crosses and ultimately, within-breed selection for higher productivity, on straw-based diets. (author)

Recovery of Hafnia alvei from diseased brown trout, Salmo trutta L., and healthy noble crayfish, Astacus astacus (L.), in Bulgaria.

Science.gov (United States)

Orozova, P; Sirakov, I; Chikova, V; Popova, R; Al-Harbi, A H; Crumlish, M; Austin, B

2014-10-01

Hafnia alvei was isolated in Bulgaria from healthy noble crayfish, Astacus astacus (L.), and then from farmed diseased brown trout, Salmo trutta L., with signs of haemorrhagic septicaemia. The isolates were identified initially with conventional phenotyping and commercial Merlin Micronaut and API 20E rapid identification systems, followed by sequencing of the 16S rRNA gene. Hafnia alvei Bt1, Bt2 and Aa4 were of low virulence to rainbow trout and brown trout, although cytotoxicity was demonstrated by Bt1 and Bt2, but not by Aa4. © 2014 John Wiley & Sons Ltd.

Substantial improvements not seen in health behaviors following corner store conversions in two Latino food swamps

OpenAIRE

Ortega, Alexander N.; Albert, Stephanie L.; Chan-Golston, Alec M.; Langellier, Brent A.; Glik, Deborah C.; Belin, Thomas R.; Garcia, Rosa Elena; Brookmeyer, Ron; Sharif, Mienah Z.; Prelip, Michael L.

2016-01-01

Background The effectiveness of food retail interventions is largely undetermined, yet substantial investments have been made to improve access to healthy foods in food deserts and swamps via grocery and corner store interventions. This study evaluated the effects of corner store conversions in East Los Angeles and Boyle Heights, California on perceived accessibility of healthy foods, perceptions of corner stores, store patronage, food purchasing, and eating behaviors. Methods Household data ...

Heavy Metals Uptake by Asian Swamp Eel, Monopterus albus from Paddy Fields of Kelantan, Peninsular Malaysia: Preliminary Study.

Science.gov (United States)

Yin, Sow Ai; Ismail, Ahmad; Zulkifli, Syaizwan Zahmir

2012-12-01

Swamp eel, Monopterus albus is one of the common fish in paddy fields, thus it is suitable to be a bio-monitor for heavy metals pollution studies in paddy fields. This study was conducted to assess heavy metals levels in swamp eels collected from paddy fields in Kelantan, Malaysia. The results showed zinc [Zn (86.40 μg/g dry weight)] was the highest accumulated metal in the kidney, liver, bone, gill, muscle and skin. Among the selected organs, gill had the highest concentrations of lead (Pb), cadmium (Cd) and nickel (Ni) whereas muscle showed the lowest total metal accumulation of Zn, Pb, copper (Cu), Cd and Ni. Based on the Malaysian Food Regulation, the levels of Zn and Cu in edible parts (muscle and skin) were within the safety limits. However, Cd, Pb and Ni exceeded the permissible limits. By comparing with the maximum level intake (MLI), Pb, Ni and Cd in edible parts can still be consumed. This investigation indicated that M. albus from paddy fields of Kelantan are safe for human consumption with little precaution.

Sustainable management of peat swamp forest of Sarawak with special reference to ramin (Gonystylus bancanus); development of a monitoring system

NARCIS (Netherlands)

Wijdeven, S.M.J.; Meer, van der P.J.; Chai, F.Y.C.; Tan, S.; Mohizah, M.; Liam, D.

2004-01-01

Peat swamp forests in Sarawak are valuable in terms of timber and biodiversity, but heavily degraded. In order to assess the current status, potential developments and possible management interventions, an adequate monitoring system is necessary. In this study a new monitoring system is proposed,

Growth Response and Tolerance to Heavy Metals of two Swamp Species inoculated with a Plant Growth-Promoting Rhizobacteria

International Nuclear Information System (INIS)

Rodriguez-Dorantes, A.; Labra-Cardon, D.; Guerrero-Zuniga, A.; Montes-Villafan, S.

2009-01-01

Due to the sensitivity and the sequestration ability of the microbial communities to heavy metals, microbes have been used for bioremediation. Recently the application of plant growth-promoting rhizobacteria (PGPR) for the bioremediation of this kind of contaminants has been done. This study evaluated the growth response and the tolerance to heavy metals of two swamp species. (Author)

Swamp plots for dynamic aperture studies of PEP-II lattices

International Nuclear Information System (INIS)

Yan, Y.T.; Irwin, J.; Cai, Y.; Chen, T.; Ritson, D.

1995-01-01

With a newly developed algorithm using resonance basis Lie generators and their evaluation with action-angle Poisson bracket maps (nPB tracking) the authors have been able to perform fast tracking for dynamic aperture studies of PEP-II lattices as well as incorporate lattice nonlinearities in beam-beam studies. They have been able to better understand the relationship between dynamic apertures and the tune shift and resonance coefficients in the generators of the one-turn maps. To obtain swamp plots (dynamic aperture vs. working point) of the PEP-II lattices, they first compute a one-turn resonance basis map for a nominal working point and then perform nPB tracking by switching the working point while holding fixed all other terms in the map. Results have been spot-checked by comparing with element-by-element tracking

Muscle receptor organs in the crayfish abdomen: a student laboratory exercise in proprioception.

Science.gov (United States)

Leksrisawat, Bonnie; Cooper, Ann S; Gilberts, Allison B; Cooper, Robin L

2010-11-18

The primary purpose of this experiment is to demonstrate primary sensory neurons conveying information of joint movements and positions as proprioceptive information for an animal. An additional objective of this experiment is to learn anatomy of the preparation by staining, dissection and viewing of neurons and sensory structures under a dissecting microscope. This is performed by using basic neurophysiological equipment to record the electrical activity from a joint receptor organ and staining techniques. The muscle receptor organ (MRO) system in the crayfish is analogous to the intrafusal muscle spindle in mammals, which aids in serving as a comparative model that is more readily accessible for electrophysiological recordings. In addition, these are identifiable sensory neurons among preparations. The preparation is viable in a minimal saline for hours which is amenable for student laboratory exercises. The MRO is also susceptible to neuromodulation which encourages intriguing questions in the sites of modulatory action and integration of dynamic signals of movements and static position along with a gain that can be changed in the system.

Strong and stable geographic differentiation of swamp buffalo maternal and paternal lineages indicates domestication in the China/Indochina border region

NARCIS (Netherlands)

Zhang, Yi; Lu, Yongfang; Yindee, Marnoch; Li, Kuan-Yi; Kuo, Hsiao-Yun; Ju, Yu-Ten; Ye, Shaohui; Faruque, Md Omar; Li, Qiang; Wang, Yachun; Cuong, Vu Chi; Pham, Lan Doan; Bouahom, Bounthong; Yang, Bingzhuang; Liang, Xianwei; Cai, Zhihua; Vankan, Dianne; Manatchaiworakul, Wallaya; Kowlim, Nonglid; Duangchantrasiri, Somphot; Wajjwalku, Worawidh; Colenbrander, Ben; Zhang, Yuan; Beerli, Peter; Lenstra, Johannes A; Barker, J Stuart F

The swamp type of the Asian water buffalo is assumed to have been domesticated by about 4000 years BP, following the introduction of rice cultivation. Previous localizations of the domestication site were based on mitochondrial DNA (mtDNA) variation within China, accounting only for the maternal

Two new species of freshwater crayfish of the genus Faxonius (Decapoda: Cambaridae) from the Ozark Highlands of Arkansas and Missouri.

Science.gov (United States)

Fetzner, James W Jr; Taylor, Christopher A

2018-03-22

Two new species of freshwater crayfish are described from the Ozarks Plateau of northern Arkansas and southern Missouri. Both species are restricted to the mainstem of rocky streams that are at least fourth-order or greater in size. Recent genetic and morphological investigations of the coldwater crayfish, Faxonius eupunctus Williams, 1952, indicated that it was actually composed of several undescribed species. Faxonius eupunctus is herein restricted to just the Eleven Point River system. Faxonius roberti, new species is found in the mainstem of the Spring and Strawberry river systems in northern Arkansas. It differs from F. eupunctus by lacking a male Form-I gonopod with a distal spatulate mesial process, and presence of two spines on the dorsal side of the merus, where F. eupunctus typically has 1 spine. Faxonius wagneri, new species is known from a 54 mile (86 km) stretch of the Eleven Point River mainstem, ranging from just southeast of Greer, Missouri to just north of Birdell, Arkansas. Faxonius wagneri can be differentiated from both F. eupunctus and Faxonius roberti sp. nov. by using the male Form-I and Form-II gonopods, the shape of the chelae, and the female annulus ventralis. In F. wagneri, the terminal elements of the first pleopod are almost twice as long as those in F. eupunctus and F. roberti, with the tips of the appendage reaching the posterior base of the first perieopod when the abdomen is flexed forward, whereas, in the other two species, these elements only reach the base of the second pereiopod. The species also possesses two spines on the dorsal side of the merus of the first pereiopod, which helps distinguish it from F. eupunctus.

Water-use dynamics of a peat swamp forest and a dune forest in Maputaland, South Africa

Directory of Open Access Journals (Sweden)

A. D. Clulow

2013-05-01

Full Text Available Peat swamp forests are the second rarest forest type found in South Africa while dune forests have been under severe threat through mining and agriculture. Both forest types exist in the conservation area, and World Heritage site, known as the iSimangaliso Wetland Park on the East coast of South Africa. The area is prone to severe droughts (Taylor et al., 2006 and recent attempts to understand the local water balance revealed that there was insufficient information on the water use of the indigenous forests of the area. The peat swamp forest and dune forest sites studied in this research were located within close proximity to each other, yet, are characterised by different landscape positions in terms of water availability. The coastal dune forest soil profile was generally dry and sandy and the tree roots did not have access to the water table. In contrast the peat swamp forest is located in an interdunal wetland where the trees have permanent access to water. The climate at both sites is subtropical with a mean annual precipitation of 1200 mm yr−1. However, over 20 months of measurement, the first summer (October 2009 to March 2010 was drier (424 versus 735 mm than the second summer (October 2010 to March 2011 emphasising the variability of the rainfall in the area and providing a wide range of conditions measured. The sap flow of an evergreen, overstory Syzygium cordatum and a semi-deciduous, understory Shirakiopsis elliptica were measured in the peat swamp forest using the heat ratio method. The Syzygium cordatum water use was not highly seasonal and the daily maximum water use ranged from approximately 30 L d−1 in winter to 45 L d−1 in summer whereas the extit{Shirakiopsis elliptica} water use was more seasonal at 2 L d−1 in winter and 12 L d−1 in summer. The water use of the Syzygium cordatum was not influenced by seasonal rainfall variations and was actually higher in the drier summer (October 2009 to March 2010. Three trees of

Isolation of peat swamp forest foliar endophyte fungi as biofertilizer

Directory of Open Access Journals (Sweden)

Safinah Surya Hakim

2017-01-01

Full Text Available Peatland restoration activity is facing many obstacles, particularly in planting techniques and poor nutrient in peat soil. Naturally, endophytic fungi are abundant and have great potential as biofertilizer. This research investigates the potential endophytic fungi isolated from leaves of peat swamp tree species for biofertilizer. Research activities include: exploration, in vitro test to examine the phosphate solubilization and identification. Result showed that there were 360 leave segments collected from 4 sampling locations. The colonization percentage of 222 isolates ranged from 52.17% - 60.17%. Fifty seven morphospecies were selected from 222 isolates. Twelve isolates demonstrated ability to produce clear zones and ten isolates were selected for identification. It is concluded that twelve isolated demonstrated potential ability to produce clear zone and Penicillum citrinum isolate P3.10 was identified as an isolate that show the highest potential ability as a biofertilizer

Proteomic analysis of three gonad types of swamp eel reveals genes differentially expressed during sex reversal

OpenAIRE

Sheng, Yue; Zhao, Wei; Song, Ying; Li, Zhigang; Luo, Majing; Lei, Quan; Cheng, Hanhua; Zhou, Rongjia

2015-01-01

A variety of mechanisms are engaged in sex determination in vertebrates. The teleost fish swamp eel undergoes sex reversal naturally and is an ideal model for vertebrate sexual development. However, the importance of proteome-wide scanning for gonad reversal was not previously determined. We report a 2-D electrophoresis analysis of three gonad types of proteomes during sex reversal. MS/MS analysis revealed a group of differentially expressed proteins during ovary to ovotestis to testis transf...

The assessment of the habitat and water quality requirements of the stone crayfish (Austropotamobius torrentium and noble crayfish (Astacus astacus species in the rivers from the Anina Mountains (SW Romania

Directory of Open Access Journals (Sweden)

Pârvulescu L.

2011-02-01

Full Text Available The species Austropotamobius torrentium and Astacus astacus are two species known in the EU directives to require deeper understanding of their autecologic requirements before any sustainable conservation effort could be successfully applied. Therefore, the paper aims to analyze the occurrence of these two species of crayfish in the Anina Mountains (Romania in relation to several physical-chemical indicators measured on site. The results suggest that the anthropogenic impacts registered in some of the sampling sites (e.g. organic pollution and river bed modification might have triggered the disappearance of both species from the areas of the water sheds situated downstream villages and towns, deforestation sites and sewage treatment plants. The analysis suggest that both species might have similar ecologic requirements, with a BMWP score of 8 (out of a possible 10, therefore good indicators of pristine aquatic environments and with a possible toleration to pollution but only up to a moderate level. Nevertheless, the lack of cohabitation of the populations of both species at a local scale was discussed along with two possible explaining hypotheses: behavioral exclusion or different times and/or modalities of dispersal history.

IMPROVEMENT OF RICE GROWTH AND PRODUCTIVITY THROUGH BALANCE APPLICATION OF INORGANIC FERTILIZER AND BIOFERTILIZER IN INCEPTISOL SOIL OF LOWLAND SWAMP AREA

Directory of Open Access Journals (Sweden)

Neni Marlina

2014-02-01

Full Text Available The objective of this study was to obtain a proper balance dose between biofertilizer and inorganic fertilizer in order to increase the growth and yield of rice in Inceptisol soil of lowland swamp origin. Biofertilizer was made by enriching straw compost with N2 interceptor bacteria, phosphate solvent bacteria and growth stimulator bacteria isolated from swamp lowland in South Sumatra. This study was conducted from November 2012 to March 2013 in a greenhouse. The design used was completely randomized design (CRD factorial, with two treatment factors consisting of inorganic fertilizer (0,25, 50, 75 and 100% recommended dosage and biofertilizer (0, 100, 200, 300, 400 and 500 kg.ha-1. The results showed that the best treatment in term of plant height at 8 weeks after planting (WAP, the maximum number of tillers, number of productive tillers, number of grains per panicle and weight of milled dry rice were obtained in combination of 75% inorganic fertilizer and 300 - 400 kg.ha-1biofertilizer.

Immunological responses of pregnant swamp and murrah buffalo cows and calves to Toxocara (Neoascaris) vitulorum infection

International Nuclear Information System (INIS)

Amerasinghe, P.; Masoodi, M.A.; Samarasinghe, B.; Sivanathan, S.; Gunawardana, V.K.; Fernando, S.T.

1984-01-01

Swamp buffalo cows from an area where T. vitulorum infection was heavy were examined for serum antibodies. Serum from all cows showed strongly positive precipitin reactions from the 4th to 6th months of pregnancy and after parturition using homologous larval, adult worm and adult excretory and secretory antigens; these precipitins were still being detected in the sera 4-6 months after calving. The sera of calves born to these cows were negative for T. vitulorum precipitins before feeding with colostrum but a precipitin reaction was evident from 24 hours of birth. Nevertheless, patent infections developed from 19-21 days after birth and one calf died with severe diarrhoea; the remainder revealed heavy faecal Toxocara egg counts. In six calves the infection was spontaneously eliminated between 40 and 60 days after birth suggesting a 'self-cure' reaction. In a similar study involving 30 Murrah cows sera precipitins were not observed during the first 4-6 months of pregnancy. In 14 calves born to these animals serum precipitins were never observed, but the animals had T. vitulorum egg counts comparable with those in swamp buffalo calves. After an initial natural infection a strong resistance to reinfection was acquired by most calves of both breeds in that larvae did not generally develop beyond the second stage. (author)

Hydrography - HYDROGRAPHY_HIGHRES_WATERBODYDISCRETE_NHD_USGS: Lakes, Ponds, Reservoirs, Swamps, and Marshes in Watersheds of Indiana (U. S. Geological Survey, 1:24,000, Polygon Shapefile)

Data.gov (United States)

NSGIC State | GIS Inventory — HYDROGRAPHY_HIGHRES_WATERBODYDISCRETE_NHD_USGS.SHP is a polygon shapefile that contains features of lakes, ponds, reservoirs, swamps and marshes in watersheds in and...

Autonomic control of the heart in the Asian swamp eel (Monopterus albus)

DEFF Research Database (Denmark)

Iversen, Nina Kerting; Huong, Do Thi Thanh; Bayley, Mark

2011-01-01

The Asian swamp eel (Monopterus albus) is an air-breathing teleost with very reduced gills that uses the buccal cavity for air-breathing. Here we characterise the cardiovascular changes associated with the intermittent breathing pattern in M. albus and we study the autonomic control of the heart.......3 cm H2O). The autonomic control of the heart during water- and air-breathing was revealed by infusion of the β-adrenergic antagonist propranolol and muscarinic antagonist atropine (3 mg kg− 1) in eels instrumented with an arterial catheter. Inhibition of the sympathetic and parasympathetic...... innervations of the heart revealed a strong vagal tone on the heart of water-breathing eels and that the tachycardia during air-breathing is primarily mediated by withdrawal of cholinergic tone....

Sunken wood habitat for thiotrophic symbiosis in mangrove swamps.

Science.gov (United States)

Laurent, Mélina C Z; Gros, Olivier; Brulport, Jean-Pierre; Gaill, Françoise; Bris, Nadine Le

2009-03-01

Large organic falls to the benthic environment, such as dead wood or whale bones, harbour organisms relying on sulfide-oxidizing symbionts. Nothing is known however, concerning sulfide enrichment at the wood surface and its relation to wood colonization by sulfide-oxidizing symbiotic organisms. In this study we combined in situ hydrogen sulfide and pH measurements on sunken wood, with associated fauna microscopy analyses in a tropical mangrove swamp. This shallow environment is known to harbour thiotrophic symbioses and is also abundantly supplied with sunken wood. A significant sulfide enrichment at the wood surface was revealed. A 72h sequence of measurements emphasized the wide fluctuation of sulfide levels (0.1->100muM) over time with both a tidal influence and rapid fluctuations. Protozoans observed on the wood surface were similar to Zoothamnium niveum and to vorticellids. Our SEM observations revealed their association with ectosymbiotic bacteria, which are likely to be sulfide-oxidizers. These results support the idea that sunken wood surfaces constitute an environment suitable for sulfide-oxidizing symbioses.

Importance of small fishes and invasive crayfish in otter Lutra lutra diet in an English chalk stream

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Britton J. Robert

2017-01-01

Full Text Available The diet composition of the European otter Lutra lutra was assessed using spraint analysis in the Hampshire Avon, a lowland chalk stream in Southern England, over an 18-month period. Small cyprinid fishes were the main prey item taken in all seasons, with bullhead Cottus gobio and stone loach Barbatula barbatula also important; there were relatively few larger fishes of interest to fisheries found. There were significant seasonal differences in diet composition by season, with signal crayfish Pacifastacus leniusculus only being prominent prey items in warmer months and amphibians in winter, revealing that non-fish resources were seasonally important dietary components. Reconstructed body lengths of prey revealed the only species present in diet >350 mm was pike Esox lucius. These dietary data thus provide important information for informing conservation conflicts between otters and fishery interests.

Water quality study at the Congaree Swamp National monument of Myers Creek, Reeves Creek and Toms Creek. Technical report

International Nuclear Information System (INIS)

Rikard, M.

1991-11-01

The Congaree Swamp National Monument is one of the last significant near virgin tracts of bottom land hardwood forests in the Southeast United States. The study documents a water quality monitoring program on Myers Creek, Reeves Creek and Toms Creek. Basic water quality parameters were analyzed. High levels of aluminum and iron were found, and recommendations were made for further monitoring

Three approaches to the classification of inland wetlands. [Dismal Swamp, Tennessee, and Florida

Science.gov (United States)

Gammon, P. T.; Malone, D.; Brooks, P. D.; Carter, V.

1977-01-01

In the Dismal Swamp project, seasonal, color-infrared aerial photographs and LANDSAT digital data were interpreted for a detailed analysis of the vegetative communities in a large, highly altered wetland. In Western Tennessee, seasonal high altitude color-infrared aerial photographs provided the hydrologic and vegetative information needed to map inland wetlands, using a classification system developed for the Tennessee Valley Region. In Florida, color-infrared aerial photographs were analyzed to produce wetland maps using three existing classification systems to evaluate the information content and mappability of each system. The methods used in each of the three projects can be extended or modified for use in the mapping of inland wetlands in other parts of the United States.

Effect of Carbohydrate Source and Cottonseed Meal Level in the Concentrate on Feed Intake, Nutrient Digestibility, Rumen Fermentation and Microbial Protein Synthesis in Swamp Buffaloes

Directory of Open Access Journals (Sweden)

M. Wanapat

2013-07-01

Full Text Available The objective of this study was to investigate the effect of carbohydrate source and cottonseed meal level in the concentrate on feed intake, nutrient digestibility, rumen fermentation and microbial protein synthesis in swamp buffaloes. Four, 4-yr old rumen fistulated swamp buffaloes were randomly assigned to receive four dietary treatments according to a 2×2 factorial arrangement in a 4×4 Latin square design. Factor A was carbohydrate source; cassava chip (CC and CC+rice bran at a ratio 3:1 (CR3:1, and factor B was level of cottonseed meal (CM; 109 g CP/kg (LCM and 328 g CP/kg (HCM in isonitrogenous diets (490 g CP/kg. Buffaloes received urea-treated rice straw ad libitum and supplemented with 5 g concentrate/kg BW. It was found that carbohydrate source did not affect feed intake, nutrient intake, digested nutrients, nutrient digestibility, ammonia nitrogen concentration, fungi and bacterial populations, or microbial protein synthesis (p>0.05. Ruminal pH at 6 h after feeding and the population of protozoa at 4 h after feeding were higher when buffalo were fed with CC than in the CR3:1 treatment (p0.05. Based on this experiment, concentrate with a low level of cottonseed meal could be fed with cassava chips as an energy source in swamp buffalo receiving rice straw.

Ground survey of red lechwe in the Linyanti swamps and Chobe floodplains, northern Botswana

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Phemelo Gadimang

2017-05-01

Full Text Available A ground survey of red lechwe was carried out in the Linyanti swamps and the Chobe floodplains of northern Botswana in the dry and wet seasons of 2012 and 2013, respectively. We documented numbers, sex ratio and age structure of red lechwe within the linear strips of 25 km × 300 m along the Linyanti swamps and the Chobe floodplains. Results indicated a significant difference in the numbers of red lechwe between sites and seasons. About 66 and 755 red lechwe were estimated for Chobe in the dry and wet season, respectively, with 343 and 261 of them estimated for Linyanti in the dry and wet season, respectively. In Chobe, the red lechwe densities varied widely between seasons (9 red lechwe/km2 – 101 red lechwe/km2 compared with Linyanti, where the densities did not vary much between seasons (35 red lechwe/km2 – 46 red lechwe/km2 . The lower densities of red lechwe in Chobe in the dry season when compared with the wet season suggest a possible seasonal shift in the distribution of red lechwe to the nearby Zambezi floodplains in Namibia. Conservation implications: The higher number of red lechwe in the Chobe floodplains in the wet season indicates the potential of the floodplains as a habitat for this species in that season. The dry season shift in the distribution of red lechwe in Chobe presents an opportunity for local communities in Namibia to engage in tourism, whereas the return of the red lechwe to the floodplains in the wet season ensures protection of the animals as well as boosts the tourism potential of the Chobe National Park.

Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

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Letícia S. Machado

Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

Identifying the best season for mapping evergreen swamp and mangrove species using leaf-level spectra in an estuarine system in KwaZulu-Natal, South Africa

CSIR Research Space (South Africa)

Van Deventer, Heidi

2014-10-01

Full Text Available would provide the best discrimination of six evergreen tree species, associated with swamp (Ficus Trichopoda), mangrove (Avicennia marina, Bruguiera gymnorrhiza, Hibiscus tiliaceus), wetlands in adjacent woodlands (Syzygium cordatum) and coastal...

Effect of day or night grazing on behaviour of swamp buffalo heifers

Directory of Open Access Journals (Sweden)

Somparn, P.

2007-03-01

Full Text Available An experiment was conducted to examine the effect of day or night grazing on behaviour by swamp buffaloes. A grazing trial was conducted over 42 days in the late rainy season, during September to November2005 at Surin Livestock Research and Breeding Center, Surin province. The experimental period was divided into two 21-day periods. Twelve 2-year-old swamp buffalo heifers were allocated to four groups, eachcontaining three heifers, with the mean group weights being as similar as possible. Each group was allowed to graze either from 06:20 to 18:00 h (daytime treatment or from 18:20 to 06:00 h (nighttime treatment infour separate paddocks, each of 5 rai, using a cross-over design. When not at pasture the animals in each group were kept in the common corral with free access to fresh drinking water and mineral blocks. Individualanimal activity was recorded by visual observation at 1-min intervals during the period at pasture. Individual groups within each period were treated as replicates. Differences between group means weretested using MIXED procedure of SAS.The buffaloes on daytime treatment spent longer (P<0.05 grazing than those on nighttime treatment (423 vs 332 min. The number of meals differed (P<0.05 between treatments, but overall mean meal durationswere similar (73 min. Buffaloes allowed to graze during daylight had a tendency (P<0.10 toward a higher bite and step rates than those grazing during the night. With the reduction in grazing activity duringthe night on nighttime treatment, the animals ruminated for longer during the period at pasture (327 and 191 min, P<0.001. Live-weight change over periods of 20 days did not differ significantly. The difference intemporal behaviour patterns between treatments indicated that animals have to adapt foraging strategies appropriate for different situations in order to maintain feed intake and subsequently production.

How does conversion from peat swamp forest to oil palm plantation affect emissions of nitrous oxide from the soil? A case study in Jambi, Indonesia

Science.gov (United States)

Hartill, Jodie; Hergoualc'h, Kristell; Comeau, Louis-Pierre; Jo, Smith; Lou, Verchot

2017-04-01

Half of the peatlands across Peninsular Malaysia, Borneo and Sumatra are 'managed'. Conversion of peat swamp forest to workable oil palm plantation requires a drastic, potentially irreversible, change to the landscape, to which fertilizers are then routinely applied. A combination of these factors is now widely thought to increase soil nitrous oxide (N2O) emissions, although there is high uncertainty due to gaps in the knowledge, both regionally and nationally. Despite the widespread use of fertilizers in plantations on peats, studies observing their effects remain very limited. Therefore, there is a need for in situ studies to evaluate how environmental parameters (edaphic properties, climate, soil moisture and N availability indicators) influence soil emissions. This 18 month study was located in plots local to each other, representing the start, intermediate and end of the land conversion process; namely mixed peat swamp forest, drained and logged forest and industrial oil palm plantation. Spatial variability was taken into account by differentiating the hollows and hummocks in the mixed peat swamp forest, and the fertilized zone and the zone without fertilizer addition in the oil palm plantation. Gas samples were collected each month from static chambers at the same time as key environmental parameters were measured. Intensive sampling was performed during a 35 day period following two fertilizer applications, in which urea was applied to palms at rates of 0.5 and 1 kg urea palm-1. Soil N2O emissions (kg N ha-1 y-1 ± SE) were low overall, but they were greater in the oil palm plantation (0.8 ± 0.1) than in the mixed peat swamp forest (0.3 ± 0.0) and the drained/logged forest (0.2 ± 0.0). In the mixed peat swamp forest, monthly average fluxes of N2O (g N ha-1 d-1 ± SE) were similar in the hollows (0.6 ± 0.2) and the hummocks (0.3 ± 0.1), whereas in the oil palm plantation they were consistently higher in the zone without fertilizer (2.5 ± 0.4) than in

Photodynamic damage of glial cells in crayfish ventral nerve cord

Science.gov (United States)

Kolosov, M. S.; Duz, E.; Uzdensky, A. B.

2011-03-01

Photodynamic therapy (PDT) is a promising method for treatment of brain tumors, the most of which are of glial origin. In the present work we studied PDT-mediated injury of glial cells in nerve tissue, specifically, in abdominal connectives in the crayfish ventral nerve cord. The preparation was photosensitized with alumophthalocyanine Photosens and irradiated 30 min with the diode laser (670 nm, 0.1 or 0.15 W/cm2). After following incubation in the darkness during 1- 10 hours it was fluorochromed with Hoechst 33342 and propidium iodide to reveal nuclei of living, necrotic and apoptotic cells. The chain-like location of the glial nuclei allowed visualization of those enveloping giant axons and blood vessels. The level of glial necrosis in control preparations was about 2-5 %. Apoptosis was not observed in control preparations. PDT significantly increased necrosis of glial cells to 52 or 67 % just after irradiation with 0.1 or 0.15 W/cm2, respectively. Apoptosis of glial cells was observed only at 10 hours after light exposure. Upper layers of the glial envelope of the connectives were injured stronger comparing to deep ones: the level of glial necrosis decreased from 100 to 30 % upon moving from the connective surface to the plane of the giant axon inside the connective. Survival of glial cells was also high in the vicinity of blood vessels. One can suggest that giant axons and blood vessels protect neighboring glial cells from photodynamic damage. The mechanism of such protective action remains to be elucidated.

Effect of uranium chronic exposure on the moult in crayfish

International Nuclear Information System (INIS)

Simon, O.; Camilleri, V.; Garnier-Laplace, J.

2004-01-01

Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

Effect of uranium chronic exposure on the moult in crayfish

Energy Technology Data Exchange (ETDEWEB)

Simon, O.; Camilleri, V.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

2004-07-01

Throughout any ecological risk assessment, one can try to establish a link between pollutant in the ecosystem and adverse biological effects. A number of methodological approaches are based on the development of the use of bio-markers such as the enzyme activity measurements (biotransformation enzymes, antioxidant enzymes) and/or bioaccumulation markers (metal in target-organs). These data allow obtaining an early-warning signal of exposure and potential involved effects and help risk management. However, the effects at higher hierarchical levels (organism or population) are not frequently considered because they tend to occur after longer exposure periods. On the basis of previous results obtained to quantify uranium biokinetics in the crayfish Orconectes limosus and to understand the influence of the exposure pathway, a chronic exposure experiment was performed for 100 days at an environmentally relevant uranium concentration in water (low level concentration ranging from?? to 100 nM). The main effect studied was focused on the moult; moulted animals being the most sensitive to pollutants. Effects on the moult process were assessed in terms of occurrence, delay, and success. Preliminary results that indicated no induction of the moult by U exposure and better survival rate to uranium exposure must be confirmed. Simultaneously, both enzymatic bio-markers of effect quantifying the oxidative status (catalase, superoxide dismutase and glutathione peroxidases) and markers of exposure (uranium distribution at organs and cellular levels and MET observations) were studied. Results obtained from complementary experiments on the uranium fluxes all over moult states were used to discuss the link between bio-markers responses and observed effects on the moult. (author)

The effect of sodium ions on the light-induced 86Rb release from the isolated crayfish retina

International Nuclear Information System (INIS)

Hartung, K.; Stieve, H.

1980-01-01

The effect of low external Na + concentrations on the light-induced K + release from crayfish photoreceptor cells was tested by labelling intracellular K + with the isotope 86 Rb. The amount of isotope released per light, stimulus is roughly proportional to the external Na + concentration if the osmolarity is kept constant by replacing Na + with Tris, choline or sucrose. When sucrose is used to replace the depleted Na + the light-induced K + release is a linear function of the external Na + concentration and is reduced by approx. 95% at an external Na + concentration of 5 mmol/l. For choline and Tris substitutions the relationships are less clear but at Na + concentrations + release is smaller in a Tris solution and larger in a choline solution. It is suggested that the light-induced K + release is due mainly to an activation of voltage sensitive K + channels. (orig.)

Similarity of 241Am and 59Fe speciation in selected freshwaters and of their adsorption on crayfish exoskeleton

International Nuclear Information System (INIS)

Vangenechten, J.H.D.; Chughtai, N.A.; Bierkens, J.; Vanderborght, O.L.J.

1987-01-01

The particulate fraction and the organically complexed fraction of freshly added 241 Am and 59 Fe were determined in 21 prefiltered surface waters. The adsorptive behaviour of both radionuclides on a biological surface (isolated carapace segments of crayfish) was tested simultaneously. A striking similarity was observed in the chemical and absorptive behaviours of both radionuclides. The stoichiometry of particulate formation revealed a 3/4, Am to Fe ratio. This same stoichiometric relationship was observed in organic complexation, while adsorptive behaviour was characterised by a 1/1, Am to Fe ratio. It is concluded that Am predictably follows the chemistry of freshly added Fe at least over a 15 day period. This observation may find interesting application in risk assessment where use can be made of the well-known geochemical cycling of iron to predict the behaviour of man-made Am. (author)

What vaccination studies tell us about immunological memory within the innate immune system of cultured shrimp and crayfish.

Science.gov (United States)

Chang, Yu-Hsuan; Kumar, Ramya; Ng, Tze Hann; Wang, Han-Ching

2018-03-01

The possibility of immunological memory in invertebrates is a topic that has recently attracted a lot of attention. Today, even vertebrates are known to exhibit innate immune responses that show memory-like properties, and since these responses are triggered by cells that are involved in the innate immune system, it seems that immune specificity and immune memory do not necessarily require the presence of B cells and T cells after all. This kind of immune response has been called "immune priming" or "trained immunity". In this report, we review recent observations and our current understanding of immunological memory within the innate immune system in cultured shrimp and crayfish after vaccination with live vaccine, killed vaccine and subunit vaccines. We also discuss the possible mechanisms involved in this immune response. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

OpenAIRE

Suciatmih Suciatmih

2003-01-01

In order to describe the vesicular-arbuscular mycorrhizal (VAM) status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2%) high level, 32 (66.7%) medium level, and 2(4.1%) low level respectively.

Nitric oxide-mediated intersegmental modulation of cycle frequency in the crayfish swimmeret system.

Science.gov (United States)

Yoshida, Misaki; Nagayama, Toshiki; Newland, Philip

2018-05-21

Crayfish swimmerets are paired appendages located on the ventral side of each abdominal segment that show rhythmic beating during forward swimming produced by central pattern generators in most abdominal segments. For animals with multiple body segments and limbs, intersegmental coordination of central pattern generators in each segment is crucial for the production of effective movements. Here we develop a novel pharmacological approach to analyse intersegmental modulation of swimmeret rhythm by selectively elevating nitric oxide levels and reducing them with pharmacological agents, in specific ganglia. Bath application of L-arginine, the substrate NO synthesis, increased the cyclical spike responses of the power-stroke motor neurons. By contrast the NOS inhibitor, L-NAME decreased them. To determine the role of the different local centres in producing and controlling the swimmeret rhythm, these two drugs were applied locally to two separate ganglia following bath application of carbachol. Results revealed that there was both ascending and descending intersegmental modulation of cycle frequency of the swimmeret rhythm in the abdominal ganglia and that synchrony of cyclical activity between segments of segments was maintained. We also found that there were gradients in the strength effectiveness in modulation, that ascending modulation of the swimmeret rhythm was stronger than descending modulation. © 2018. Published by The Company of Biologists Ltd.

Chronological Reorganization of Microtubules, Actin Microfilaments, and Chromatin during the First Cell Cycle in Swamp Buffalo (Bubalus bubalis Embryos

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Vibuntita Chankitisakul

2010-01-01

Full Text Available This paper aimed to study the dynamics of early embryonic development, in terms of redistribution of cytoskeleton (microtubules, actin microfilaments and chromatin configurations during the first cell cycle in swamp buffalo embryos. Oocytes were matured and fertilized in vitro, and they were fixed at various time points after IVF. At 6 h after IVF, 44.4% matured oocytes were penetrated by spermatozoa. Partial ZP digestion, however, did not improve fertilization rate compared to control (P>.05. At 12 h after IVF, the fertilized oocytes progressed to the second meiotic division and formed the female pronucleus simultaneously with the paternal chromatin continued to decondense. A sperm aster was observed radiating from the base of the decondensing sperm head. At 18 h after IVF, most presumptive zygotes had reached the pronuclear stage. The sperm aster was concurrently enlarged to assist the migration and apposition of pronuclei. Cell cleavage was facilitated by microfilaments and firstly observed by 30 h after IVF. In conclusion, the cytoskeleton actively involves with the process of fertilization and cleavage in swamp buffalo oocytes. The centrosomal material is paternally inherited. Fertilization failure is predominantly caused by poor sperm penetration. However, partial digestion of ZP did not improve fertilization rate.

Modification of sodium and potassium channel kinetics by diethyl ether and studies on sodium channel inactivation in the crayfish giant axon membrane

Energy Technology Data Exchange (ETDEWEB)

Bean, Bruce Palmer [Univ. of Rochester, NY (United States)

1979-01-01

The effects of ether and halothane on membrane currents in the voltage clamped crayfish giant axon membrane were investigated. Concentrations of ether up to 300 mM and of halothane up to 32 mM had no effect on resting potential or leakage conductance. Ether and halothane reduced the size of sodium currents without changing the voltage dependence of the peak currents or their reversal potential. Ether and halothane also produced a reversible, dose-dependent speeding of sodium current decay at all membrane potentials. Ether reduced the time constants for inactivation, and also shifted the midpoint of the steady-state inactivation curve in the hyperpolarizing direction. Potassium currents were smaller with ether present, with no change in the voltage dependence of steady-state currents. The activation of potassium channels was faster with ether present. There was no apparent change in the capacitance of the crayfish giant axon membrane with ether concentrations of up to 100 mM. Experiments on sodium channel inactivation kinetics were performed using 4-aminopyridine to block potassium currents. Sodium currents decayed with a time course generally fit well by a single exponential. The time constant of decay was a steep function of voltage, especially in the negative resistance region of the peak current vs voltage relation.The time course of inactivation was very similar to that of the decay of the current at the same potential. The measurement of steady-state inactivation curves with different test pulses showed no shifts along the voltage asix. The voltage-dependence of the integral of sodium conductance was measured to test models of sodium channel inactivation in which channels must open before inactivating; the results appear inconsistent with some of the simplest cases of such models.

Vesicular-arbuscular mycorrhizal status of plant species in the peat swamp forest of Setia Alam Jaya, Sebangau, Central Kalimantan

Directory of Open Access Journals (Sweden)

Suciatmih Suciatmih

2003-06-01

Full Text Available In order to describe the vesicular-arbuscular mycorrhizal (VAM status of plants growing on peat soil, a study was carried out inthe peat swamp forest of Setia Alam Jaya in Sebangau, Central Kalimantan. Out of 146 plant root samples belonging to 48 plantspecies from 25 families examined, all plants colonized by VAM fungi namely 14 (29.2% high level, 32 (66.7% medium level, and 2(4.1% low level respectively.

Pseudocapillaria (Ichthyocapillaria) ophisterni sp. n. (Nematoda : Capillariidae) from the swamp-eel Ophisternon aenigmaticum (Pisces) in Mexico.

Science.gov (United States)

Moravec, F; Salgado-Maldonado, G; Jiménez-García, I

2000-04-01

A new nematode species, Pseudocapillaria ophisterni sp. n., is described from the intestine and rarely from the stomach of the swamp-eel, Ophisternon aenigmaticum Rosen et Greenwood, from Catemaco Lake, Veracruz, Mexico. In having both caudal lobes in the male interconnected by a distinct dorsal membrane, it belongs to the subgenus Ichthyocapillaria. It differs from the three species in this subgenus mainly in possessing either a distinctly longer spicule or a smaller length of oesophagus relative to body length. It also differs in host type and geographical distribution. P. ophisterni is the first capillariid species reported from synbranchiform fishes.

American black bears and bee yard depredation at Okefenokee Swamp, Georgia

Science.gov (United States)

Clark, J.D.; Dobey, S.; Masters, D.V.; Scheick, B.K.; Pelton, M.R.; Sunquist, M.E.

2005-01-01

We studied American black bears (Ursus americanus), on the northwest periphery of Okefenokee Swamp in southeast Georgia, to assess landowner attitudes toward bears, estimate the extent of damage to commercial honey bee operations by bears, and evaluate methods to reduce bear depredations to apiaries. We collected 8,351 black bear radiolocations and identified 51 bee yards on our study area. Twenty-seven of 43 home ranges contained ≥1 bee yard, averaging 11.3 and 5.1 bee yards/home range of males (n = 7) and females (n = 20), respectively. From 1996 to 1998, we documented 7 instances of bears raiding bee yards within our study area and 6 instances in adjacent areas. All but 1 of the 13 raided yards were enclosed by electric fencing. In the 12 cases of damage to electrically fenced yards, however, the fences were not active because of depleted batteries. Based on compositional analysis, bear use of areas 800–1,400 m from bee yards was disproportionately greater than use 0–800 m from bee yards. Bears disproportionately used bay (red bay: Persea borbonia, loblolly bay: Gordonia lasianthus, and southern magnolia: Magnolia virginia), gum (water tupelo: Nyssa aquatic and black gum: N. sylvatica), and cypress (Taxodium spp.) and loblolly bay habitats, however, compared with slash pine (Pinus elliottii) or pine–oak (Quercus spp.), where bee yards usually were placed. The distribution of bear radiolocations likely reflected the use of those swamp and riparian areas, rather than avoidance of bee yards. Distances to streams from damaged bee yards (x̄ = 1,750 m) were less than from undamaged yards (x̄ = 4,442 m), and damaged bee yards were closer to unimproved roads (x̄ = 134 m) than were undamaged bee yards (x̄ = 802 m). Our analysis suggests that bee yard placement away from bear travel routes (such as streams and unimproved roads) can reduce bear depredation problems. Our results strongly indicate that working electric fences are effective deterrents to bear

Primary production in a shallow water lake with special reference to a reed swamp

International Nuclear Information System (INIS)

Andersen, F.Oe.

1976-01-01

Phytoplankton gross primary production ( 14 C method) in the shallow, eutrophic Danish Lake Arresoe in 1973 was 980 g C m -2 . Calculated net primary production was near zero. Macrophyte net primary production was measured by harvesting the maximum biomass, and above ground values were between 420 and 1325 g ash free dry wt m -2 , while below ground values were between 2480 and 8570 g ash free dry wt m -2 . The reed swamps were mapped on aerial photographs, and the composition of the macrophyte vegetation was determined. A comparison of macrophyte vegetation in 1944 and 1972 showed a reduction in species diversity, especially of submerged species. The seasonal variations in physical and chemical data indicated strong eutrophication in Arresoe. (author)

EFFECT OF ARBUSCULAR MYCORRHIZAL COLONIZATION ON EARLY GROWTH AND NUTRIENT CONTENT OF TWO PEAT­ SWAMP FOREST TREE SPECIES SEEDLINGS, Calophyllum hosei AND Ploiarium alternifolium

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Maman Turjaman

2006-03-01

Full Text Available Tropical peat-swamp forests are one of  the largest near-surface reserves of terrestrial organic carbon,  but rnany peat-swamp forest tree species decreased due over-exploitation, forest fire and conversion of natural forests into agricultural lands. Among those species are slow-growing Calophyllum  hoseiand Ploiarium  alternifolium, two species are good for construction of boats, furniture, house building and considerable attention from pharmacological viewpoint for human healthly. This study was aimed at understanding the effects of arbuscular mycorrhizal (AM fungi on early growth of  C. hosei and P.alternifoliumunder greenhouse condition. Seedlings of C. hosei and P.alternifoliumwere inoculated with AM fungi: Glomus clarum and Glomus aggregatum ,or uninoculated under greenhouse condition during 6 months. AM colonization,   plant growth,  survival rate and  nutrient  content  (P, Zn  and B were measured. The percentage of C. hoseiand P.alternifolium ranged from 27-32% and 18-19%,  respectively. Both inoculated seedling species had greater plant  height, diameter, leaf number, shoot and root dry weight than control  seedlings.   Nutrient  content  of  inoculated  plants  were increased with AM colonization- Survival rates of  inoculated plants were higher (100%  than those of  control plants (67%. The results suggested that inoculation of AM fungi could improve the early growth of C. hoseiand P.alternifolium grown in tropical peat-swamp forest therefore  this finding has greater potential impact if this innovative technology applied in field scales which are socially acceptable, commercially profitable and environmentally friendly.

Postpartum anoestrus in the suckled swamp buffalo

International Nuclear Information System (INIS)

Jainudeen, M.R.; Sharifuddin, W.; Yap, K.C.; Bakar Dahari, A.

1984-01-01

Postpartum anoestrus is a serious cause of infertility in the swamp buffalo. Our studies have revealed that it is due to a failure in the resumption of ovarian cyclicity. Parity was inversely related to the calving interval being longer in primiparous than multiparous suckled buffaloes. This effect may be partly due to the higher nutrient demands for growth as well as for lactation in the primiparous animal. The effects of suckling on ovarian and pituitary function of postpartum buffaloes were investigated with the aid of radioimmunoassays for progesterone and luteinizing hormone (LH) as well as rectal palpation and laparoscopic inspection of the ovaries. The incidence of postpartum anoestrus was higher in suckled than non-suckled buffaloes. Weaning buffalo calves at 30 d postpartum resulted in the resumption of normal ovarian cycles within 60 d postpartum. LH release in response to a single injection of a synthetic gonadotropin-releasing hormone (GnRH) indicated that pituitary responsiveness to GnRH was restored by Day 30 postpartum in suckled buffaloes whereas anoestrous buffaloes were able to release levels of LH comparable to that of the preovulatory surge. A progesterone-releasing intra-vaginal device (PRID) induced an anovulatory oestrus in the anoestrous suckled buffalo which was partially overcome by human chorionic gonadotropin (HCG) administered at the induced oestrus. However, a 72 h separation of the calf from its dam combined with PRID was the most effective substitute to weaning in initiating ovarian cycles in the suckled buffalo. Our data suggest that suckling inhibits ovarian function not by an effect on the pituitary gland but rather on GnRH release by the hypothalamus. (author)

Firing Room Remote Application Software Development & Swamp Works Laboratory Robot Software Development

Science.gov (United States)

Garcia, Janette

2016-01-01

The National Aeronautics and Space Administration (NASA) is creating a way to send humans beyond low Earth orbit, and later to Mars. Kennedy Space Center (KSC) is working to make this possible by developing a Spaceport Command and Control System (SCCS) which will allow the launch of Space Launch System (SLS). This paper's focus is on the work performed by the author in her first and second part of the internship as a remote application software developer. During the first part of her internship, the author worked on the SCCS's software application layer by assisting multiple ground subsystems teams including Launch Accessories (LACC) and Environmental Control System (ECS) on the design, development, integration, and testing of remote control software applications. Then, on the second part of the internship, the author worked on the development of robot software at the Swamp Works Laboratory which is a research and technology development group which focuses on inventing new technology to help future In-Situ Resource Utilization (ISRU) missions.

Similarity of /sup 241/Am and /sup 59/Fe speciation in selected freshwaters and of their adsorption on crayfish exoskeleton

Energy Technology Data Exchange (ETDEWEB)

Vangenechten, J.H.D.; Chughtai, N.A.; Bierkens, J.; Vanderborght, O.L.J.

1987-01-01

The particulate fraction and the organically complexed fraction of freshly added /sup 241/Am and /sup 59/Fe were determined in 21 prefiltered surface waters. The adsorptive behaviour of both radionuclides on a biological surface (isolated carapace segments of crayfish) was tested simultaneously. A striking similarity was observed in the chemical and absorptive behaviours of both radionuclides. The stoichiometry of particulate formation revealed a 3/4, Am to Fe ratio. This same stoichiometric relationship was observed in organic complexation, while adsorptive behaviour was characterised by a 1/1, Am to Fe ratio. It is concluded that Am predictably follows the chemistry of freshly added Fe at least over a 15 day period. This observation may find interesting application in risk assessment where use can be made of the well-known geochemical cycling of iron to predict the behaviour of man-made Am.

Food habitats of the Antillean manatees (Trichechus manatus manatus) in the Coswine Swamps (French Guiana, South America)

OpenAIRE

Spiegelberger, Thomas; Ganslosser, Udo

2005-01-01

A study was conducted to analyse the habitat of the Antillean manatee (Trichechus manatus manatus L. 1758) in the Coswine Swamps of northwest French Guiana, South America. Water parameters were similar to those described in other studies: water depth varied from 2.5 m to more than 20 m; water temperature was between 24.5 °C and 30.3 °C and pH varied between 5.5 and 6.9. Salinity was low (0.0‰ to 1.3‰) with 86.9% of all samples taken in fresh water. No submerged aquatic vegetation was found in...

Zoneamento ambiental em Pantanais (Banhados Environmental zoning in swamp regions

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Fabio C. Kurtz

2001-05-01

Full Text Available O zoneamento ambiental em pantanais (Banhados permitiu avaliar a deterioração ambiental dos ecossistemas existentes na Estação Ecológica do Taim (ESEC/TAIM municípios de Rio Grande, RS, e Santa Vitória do Palmar, RS. Considerou-se dois tipos distintos de ecossistemas: o do Banhado (ECO1 = Ecossistema Límnico e o da Planície Marítima (ECO2 = Ecossistema Planície Marítima. A ECO TOTAL (ECO1 + ECO2 apresentou 64% da classe APP (Área de Preservação Permanente, 27,6% de ACP (Área de Conservação Permanente, e 5,6% de AUO (Área de Uso e Ocupação, enquanto em menor porcentagem se encontra a classe AR (Área de Restauração com 2,8%. A deterioração ambiental da ESEC/TAIM (ECO TOTAL ficou em 13,65%. Com relação à análise fatorial, conclui-se que esta técnica permitiu conhecer a estrutura dos dados, mostrando as correlações entre cada variável (classes de exuberância e seu respectivo fator; entretanto, não foi possível separar grupos ou quantificar a influência de uma ou mais variáveis sobre outra de interesse (variável resposta. Recomenda-se que o zoneamento ambiental seja elaborado pelos órgãos públicos ambientais, nas demais estações ecológicas e nas unidades de conservação.The environmental zoning in swamp regions allowed the evaluation of the environmental deterioration of the ecosystems in the Ecological Station of Taim (ESEC/TAIM, in Rio Grande and Santa Vitória of Palmar (in the State of Rio Grande do Sul - Brazil. Two different types of ecosystems were considered: swamp regions (ECO1 = Límnico Ecosystem and the Marine Plain (ECO2 = Ecosystem Marine Plain. The ECO TOTAL (ECO1 + ECO2 presented 64% of the class APP (Permanent Preservation Area, 27.6% of ACP (Permanent Conservation Area, 5.6% of AUO (Occupation and Use Area, and in a smaller percentage the class AR (Restoration Area with 2.8%. The environmental deterioration of ESEC/TAIM (ECO TOTAL was 13.65%. The factorial analysis technique permitted

Clonal growth strategy, diversity and structure: A spatiotemporal response to sedimentation in tropical Cyperus papyrus swamps.

Science.gov (United States)

Geremew, Addisie; Stiers, Iris; Sierens, Tim; Kefalew, Alemayehu; Triest, Ludwig

2018-01-01

Land degradation and soil erosion in the upper catchments of tropical lakes fringed by papyrus vegetation can result in a sediment load gradient from land to lakeward. Understanding the dynamics of clonal modules (ramets and genets) and growth strategies of plants on such a gradient in both space and time is critical for exploring a species adaptation and processes regulating population structure and differentiation. We assessed the spatial and temporal dynamics in clonal growth, diversity, and structure of an emergent macrophyte, Cyperus papyrus (papyrus), in response to two contrasting sedimentation regimes by combining morphological traits and genotype data using 20 microsatellite markers. A total of 636 ramets from six permanent plots (18 x 30 m) in three Ethiopian papyrus swamps, each with discrete sedimentation regimes (high vs. low) were sampled for two years. We found that ramets under the high sedimentation regime (HSR) were significantly clumped and denser than the sparse and spreading ramets under the low sedimentation regime (LSR). The HSR resulted in significantly different ramets with short culm height and girth diameter as compared to the LSR. These results indicated that C. papyrus ameliorates the effect of sedimentation by shifting clonal growth strategy from guerrilla (in LSR) to phalanx (in HSR). Clonal richness, size, dominance, and clonal subrange differed significantly between sediment regimes and studied time periods. Each swamp under HSR revealed a significantly high clonal richness (R = 0.80) as compared to the LSR (R = 0.48). Such discrepancy in clonal richness reflected the occurrence of initial and repeated seedling recruitment strategies as a response to different sedimentation regimes. Overall, our spatial and short-term temporal observations highlighted that HSR enhances clonal richness and decreases clonal subrange owing to repeated seedling recruitment and genets turnover.

The Analysis of Management and Timber Trade System of Gelam (Melaleuca cajuputi From Peat Swamp Forest in South Kalimantan

Directory of Open Access Journals (Sweden)

Yudi Firmanul Ariffin

2015-05-01

Full Text Available Until now the raw material of wood especially Gelam (Melaleuca cajuputi available for supporting the construction of housing and other infrastructures is increasingly large in Indonesia. On the Island of Borneo that partly consists of swamps needs Gelam very large and continuous, particularly for residential development. However, areas of peat swamp forest habitat of this plant from year to year are degradation and shrinkage. This situation is a very big influence on the population of Gelam, while the management and timber trade systems are not well regulated. This study aims to analyze the management and timber trade systems of Gelam particularly in South Kalimantan to provide input to the policy holder in the preservation of Gelam. The method was used a field survey and interviews with traders and policy holders related regulations. The results showed in South Kalimantan the potency of Gelam is only 2,9-7,1 m3/ha and decreasing yearly. Normally Gelam with a diameter <4 cm have been cut down, as well as > 30 cm. These dimensions should not be cut because of <4 cm too young and > 30 cm can be used as seed sources. Gelam derived from peat swamp forest, which mostly comes from the Batola District and some came from Kapuas District of Central Kalimantan. Distributions of Gelam were starting gatherers logging in the forest then sold to small gatherers, next to the large gatherers and distributed to all districts/cities in South Kalimantan, wood processing industries, and some of them were sent to Java. The silviculture system of Gelam was using selective cutting. Classification of wood sizes traded by the diameter divided into 3-4cm, 5-6cm, 7-8cm, 9-10cm, 11-12cm, 13-14cm, 15-19cm and > 20cm to 4m long. Its use consists of a small diameter (3-10cm for foundry building and firewood, while the large diameter (10-20cm for the construction of houses in swampy areas, and waste as well as the stems are bent and deformed used for firewood. Until now Gelam

Productivity of Indonesian swamp buffaloes in relation to nutrition, reproduction and draught use in the wet tropics

International Nuclear Information System (INIS)

Bamualim, A.; Liem, C.; Ffoulkes, D.

1990-01-01

Buffaloes in Indonesian villages fulfil a valuable function in providing the major source of draught power for cultivation. However, in wet irrigated areas, the continuous work of buffaloes and the low to medium quality of the available feed result in low growth rates and low reproductive performance. Results from buffalo feeding trials using similar feeds to those given in the villages indicated that high usage for draught would ultimately reduce body weight gains and might reduce the ovarian activity of buffalo cows. Use of supplements is recommended to improve the growth rates and fertility of swamp buffalo cows subjected to high work loads. (author). 14 refs, 7 tabs

Reproductive biology of the swamp racer Mastigodryas bifossatus (Serpentes: Colubridae in subtropical Brazil

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Pedro T. Leite

2009-03-01

Full Text Available The swamp racer Mastigodryas bifossatus (Raddi, 1820 is a large snake of Colubrinae. It is widely distributed in open areas throughout South America. Dissection of 224 specimens of this species housed in herpetological collections of the southern Brazilian states of Rio Grande do Sul, Santa Catarina and Paraná provided information on its sexual dimorphism, reproductive cycle and fecundity in subtropical Brazil. Adult specimens of M. bifossatus average approximately 1190 mm in snout-vent length and females are larger than males. The reproductive cycle of females is seasonal, with secondary vitellogenesis occurring from July to December. However, examination of male gonads did not reveal signs of reproductive seasonality in this sex. Egg laying was recorded from November to January. The estimated recruitment period extends from February to April. The mean number of individuals per clutch is 15, and there is a positive correlation between female length and clutch size.

Waste drilling-fluid-utilising microorganisms in a tropical mangrove swamp oilfield location

Energy Technology Data Exchange (ETDEWEB)

Benka-Coker, M.O.; Olumagin, A. [Benin Univ. (Nigeria). Dept. of Microbiology

1995-12-31

Waste drilling-fluid-utilising microorganisms were isolated from drilling-mud cuttings, soil and creek water from a mangrove swamp oilfield location in the Delta area of Nigeria using waste drilling-fluid as the substrate. Eighteen bacterial isolates obtained were identified as species of Staphylococcus, Acinetobacter, Alcaligenes, Serratia, Clostridium, Enterobacter, Klebsiella, Nocardia, Bacillus, Actinomyces, Micrococcus and Pseudomonas, while the genera of fungi isolated were Penicillium, Cladosporium and Fusarium. Even though drilling-fluid-utilising genera were in higher numbers in the soil than in the two other sources examined, the percentages of the total heterotrophic bacteria that utilised waste drilling-fluid were 6.02 in the drilling-mud cuttings, 0.83 in creek water and 0.42 in soil. The screen tests for biodegradation potential of the bacterial isolates showed that, even though all the isolates were able to degrade and utilise the waste fluid for growth, species of Alcaligenes and Micrococcus were more active degraders of the waste. The significance of the results in environmental management in oil-producing areas of Nigeria is discussed. (Author)

Waste drilling-fluid-utilising microorganisms in a tropical mangrove swamp oilfield location

International Nuclear Information System (INIS)

Benka-Coker, M.O.; Olumagin, A.

1995-01-01

Waste drilling-fluid-utilising microorganisms were isolated from drilling-mud cuttings, soil and creek water from a mangrove swamp oilfield location in the Delta area of Nigeria using waste drilling-fluid as the substrate. Eighteen bacterial isolates obtained were identified as species of Staphylococcus, Acinetobacter, Alcaligenes, Serratia, Clostridium, Enterobacter, Klebsiella, Nocardia, Bacillus, Actinomyces, Micrococcus and Pseudomonas, while the genera of fungi isolated were Penicillium, Cladosporium and Fusarium. Even though drilling-fluid-utilising genera were in higher numbers in the soil than in the two other sources examined, the percentages of the total heterotrophic bacteria that utilised waste drilling-fluid were 6.02 in the drilling-mud cuttings, 0.83 in creek water and 0.42 in soil. The screen tests for biodegradation potential of the bacterial isolates showed that, even though all the isolates were able to degrade and utilise the waste fluid for growth, species of Alcaligenes and Micrococcus were more active degraders of the waste. The significance of the results in environmental management in oil-producing areas of Nigeria is discussed. (Author)

Phylogeny and evolutionary patterns in the Dwarf crayfish subfamily (Decapoda: Cambarellinae.

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Carlos Pedraza-Lara

Full Text Available The Dwarf crayfish or Cambarellinae, is a morphologically singular subfamily of decapod crustaceans that contains only one genus, Cambarellus. Its intriguing distribution, along the river basins of the Gulf Coast of United States (Gulf Group and into Central México (Mexican Group, has until now lacked of satisfactory explanation. This study provides a comprehensive sampling of most of the extant species of Cambarellus and sheds light on its evolutionary history, systematics and biogeography. We tested the impact of Gulf Group versus Mexican Group geography on rates of cladogenesis using a maximum likelihood framework, testing different models of birth/extinction of lineages. We propose a comprehensive phylogenetic hypothesis for the subfamily based on mitochondrial and nuclear loci (3,833 bp using Bayesian and Maximum Likelihood methods. The phylogenetic structure found two phylogenetic groups associated to the two main geographic components (Gulf Group and Mexican Group and is partially consistent with the historical structure of river basins. The previous hypothesis, which divided the genus into three subgenera based on genitalia morphology was only partially supported (P = 0.047, resulting in a paraphyletic subgenus Pandicambarus. We found at least two cases in which phylogenetic structure failed to recover monophyly of recognized species while detecting several cases of cryptic diversity, corresponding to lineages not assigned to any described species. Cladogenetic patterns in the entire subfamily are better explained by an allopatric model of speciation. Diversification analyses showed similar cladogenesis patterns between both groups and did not significantly differ from the constant rate models. While cladogenesis in the Gulf Group is coincident in time with changes in the sea levels, in the Mexican Group, cladogenesis is congruent with the formation of the Trans-Mexican Volcanic Belt. Our results show how similar allopatric

A palynological study of Polynesian and European effects on vegetation in Coromandel, New Zealand, showing the variability between four records from a single swamp

International Nuclear Information System (INIS)

Byrami, M.; Ogden, J.; Horrocks, M.; Deng, Y.; Shane, P.; Palmer, J.

2002-01-01

Seven cores were extracted from a river terrace swamp in the forested Kauaeranga valley, Coromandel Peninsula, New Zealand. High-resolution (c. 36-73 yr interval) pollen records were obtained from four of the cores and aged by radiocarbon dating and with stratigraphic reference to the 665 ± 15 14 C yr BP Kaharoa Tephra. The records span the last c. 1800 yr and show that the vegetation consisted of lowland podocarp-hardwood forest before deforestation by burning occurred. The pattern of deforestation at Kauaeranga, indicated by the abrupt dominance of Pteridium with concurrent increased charcoal, is typical of pollen records associated with early Polynesian settlement in New Zealand. Peaks of Pteridium and charcoal were also found in sediments deposited after European settlement. Different cores show marked palynological and stratigraphic differences relative to the Kaharoa Tephra, most importantly with regard to the timing of deforestation. Deforestation occurred close to the Kaharoa, at a calculated age of c. 750 BP in one core but well above the Kaharoa (c. 480 BP) in another. The stratigraphic unconformities between cores are attributed to variable fluvial processes causing an uneven deposition of sediments within the swamp. (author). 32 refs., 8 figs., 4 tabs

Late-Holocene Environmental Reconstruction and Depositional History from a Taxodium Swamp near Lake Pontchartrain in Southern Louisiana

Science.gov (United States)

Ryu, J.; Bianchette, T. A.; Liu, K. B.; Yao, Q.; Maiti, K.

2017-12-01

The hydrological and environmental history of estuarine wetlands in Louisiana is not well-documented. To better understand the depositional processes in coastal wetlands, this study aims to reconstruct the environmental changes and document the occurrence of event deposits found in a bald cypress (Taxodium distichum) swamp approximately 800 m west of Lake Pontchartrain, a site susceptible to wind-generated storm surges as well as inundation from other fluvial and lacustrine processes. 210Pb analysis of a 59 cm sediment core (WMA-1) suggests that it has a sedimentation rate of 0.39 cm/year, consistent with the detection of a 137Cs peak at 17 cm from the core top. Results of sedimentological, geochemical, and palynological analyses reveal that the core contains two distinct sediment facies: an organic-rich dark brown peat unit from 0 to 29 cm containing low concentrations of terrestrial elements (e.g., Ti, Fe, and K), and a clay unit from 30 to 59 cm with elevated concentrations of most elements. Two thin clay layers, at 3-5 cm and 14-19 cm, embedded in the upper peat section are probably attributed to two recent storm events, Hurricane Isaac (2012) and Hurricane Gustav (2008), because both hurricanes caused heavy rain and significant storm-surge flooding at the study site. The pollen assemblage in the clay section is dominated by TCT (mainly Taxodium), but it is replaced by Salix and wetland herbaceous taxa in the overlying peat section. The multi-proxy data suggest that a cypress swamp has been present at the site for at least several hundred years but Taxodium was being replaced by willow (Salix) and other bottomland hardwood trees and wetland herbs as the water level dropped. Human activities may have been an important factor causing the hydrological and ecological changes at the site during the past century.

Laboratory Scale Bioremediation of Petroleum Hydrocarbon – Polluted Mangrove Swamps in the Niger Delta Using Cow Dung

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Dike, E. N.

2012-01-01

Full Text Available Aims: The aim of the study was to carry-out laboratory–scale bioremediation of petroleum hydrocarbon polluted mangrove swamps using cow dung as source of limiting of nutrients.Methodology and Results: In a 70 days study, the cow dung treated polluted soil had its total culturable hydrocarbon utilising bacterial/fungi, heterotrophic bacterial and fungal counts increased progressively from the 28th day to the 70th day. The control set- up showed very slight increment in its microbial growth. Alkaline pH was observed in all the treatments and control during the study period. The conductivity values of cow dung decreased progressively. In the cow dung treatment option, the nitrate concentration decreased from 35.44 mg/kg to 14.28 mg/kg. Phosphate concentration of cow dung option decreased from 25.41 mg/kg to 9.31mg/kg. The control had the nitrate decreased from 8.42 mg/kg to 6.98 mg/kg. Percentage total organic carbon (% TOC in the cow dung option decreased from 4.06% to 0.96%. Control experiment had the % TOC decreased from 3.32% to 2.99%. Studies using Gas chromatographic analyses showed that 0%, 49.88%, and 69.85% of Total petroleum hydrocarbon (TPH were lost at zero hour, 28th day and 70th day respectively in the cow dung option. In addition, in the control experimental set-up, 0%, 7.14% and 13.42% of TPH were lost at zero hour, 28th day and 70th day respectively.Conclusion, significance and impact of study: The use of organic nutrient sources such as cow dung has shown good promises in bioremediation of crude oil impacted Mangrove Swamps in the Niger Delta. The next line of action is to transfer the technology to pilot scale study.

Insect emergence in relation to floods in wet meadows and swamps in the River Dalälven floodplain.

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Vinnersten, T Z Persson; Östman, Ö; Schäfer, M L; Lundström, J O

2014-08-01

Annual variation in flood frequency and hydroperiod during the vegetation season has ecological impacts on the floodplain biota. Although many insect groups may have a lower emergence during a flood event, it is poorly known how annual emergence of insects in temporary wetlands is related to the variation in hydrology. Between May and September, we studied the weekly emergence of 18 insect taxa over six consecutive years, 2002-2007, in six temporary flooded wetlands (four wet meadows and two forest swamps) in the River Dalälven floodplains, Central Sweden. We used emergence traps to collect emerging insects from terrestrial and aquatic parts of wet meadows and swamp forests. In all wetlands, the insect fauna was numerically dominated by the orders Diptera, Hymenoptera, Coleoptera and Homoptera. On a weekly basis, 9 out of the 18 insect taxa had lower emergence in weeks with flood than in weeks with no flood, whereas no taxon had a higher emergence in weeks with flood. Over the seasons, we related insect emergence to seasonal flood frequency and length of hydroperiod. The emergence of most studied taxa decreased with increasing hydroperiod, which suggests that emergence after floods do not compensate for the reduced emergence during floods. Only Culicidae and the aquatic Chironomidae sub-families Tanypodinae and Chironominae showed an increase in emergence with increasing hydroperiod, whereas Staphylinidae peaked at intermediate hydroperiod. We conclude that a hydroperiod covering up to 40% of the vegetation season has a significant negative effect on the emergence of most taxa and that only a few taxa occurring in the temporary wetlands are actually favoured by a flood regime with recurrent and unpredictable floods.

NILAI EKONOMI KARBON HUTAN RAWA GAMBUT MERANG KEPAYANG, PROVINSI SUMATERA SELATAN (Economic Value of Carbon of Merang Kepayang Peat Swamp Forest, South Sumatera Province

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Nur Arifatul Ulya

2015-03-01

Full Text Available ABSTRAK Hutan rawa gambut menyimpan cadangan karbon baik di tanah maupun di atas tanah. Hutan Rawa Gambut Merang Kepayang (HRGMK merupakan kawasan hutan yang berada di kubah gambut terbesar di Sumatera Selatan, yaitu Kubah Gambut Merang (KGM, yang didalamnya terdapat gambut dengan ketebalan lebih dari 3 meter. Meskipun menurut aturan KGM seharusnya dikonservasi, pada kenyataannya kawasan HRGMK dihadapkan pada konversi. Konversi HRGMK diduga akan mengakibatkan terganggunya fungsi hutan rawa gambut sebagai cadangan karbon dunia sehingga akan menyebabkan terjadinya emisi karbon ke atmosfer dalam jumlah besar. Penelitian ini bertujuan untuk mengetahui nilai ekonomi kawasan HRGMK sebagai penyimpan cadangan karbon. Hasil penelitian diharapkan menjadi acuan pelestarian HRGMK sebagai stabilisator iklim dunia. Nilai ekonomi karbon HRGMK ditaksir dengan menggunakan harga bayangan. Harga karbon yang digunakan untuk menaksir nilai ekonomi karbon diperoleh dengan metode benefit transfer. Hasil penelitian menunjukkan bahwa nilai total karbon HRGMK adalah US$ 1.591.878.378,00 atau Rp. 14.002.162.211.645,00. Nilai tersebut sebagian besar berasal dari cadangan karbon di bawah tanah. ABSTRACT Peat swamp forests store aboveground and belowground carbon. Merang Kepayang Peat Swamp Forest (MKPSF is a forest area which is located in Merang Peat Dome (MPD, the largest peat dome in South Sumatra, with peat thickness more than 3 meters. Although the order should be conserved MPD, in fact MKPSF area exposed to the conversion. MKPSF conversion would presumably result in impaired function of peat swamp forest as world's carbon storage that will be caused carbon emissions into the atmosphere in large quantities. This study aimed to determine the economic value of the HRGMK as carbon storage. The results are expected to be justifications for conservation of MKPSF as climate stabilizers. The economic value of carbon HRGMK assessed using shadow pricing method. The carbon price

Is the herb-shrub composition of veredas (Brazilian palm swamps distinguishable?

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Diogo Pereira da Silva

2017-11-01

Full Text Available ABSTRACT Vereda (Brazilian palm swamp is a poorly known savannic phytophysiognomy that occurs on moist soils with high herb-shrub floristic richness. This study aimed to document the herb-shrub species of veredas of the Estação Ecológica Serra Geral do Tocantins - EESGTO, and compare this flora with other veredas in Brazil. Furthermore, we assessed the similarity of the herb-shrub flora of the studied veredas with that of inventories of other savannas and grasslands in order to evaluate whether veredas possess an exclusive flora. Ordination analysis was performed to understand the floristic relationship among these areas. We recorded 213 species, 105 genera and 49 families at EESGTO, including five new floral records for the Cerrado and 78 for the state of Tocantins. The floristic similarity among veredas at EESGTO and the other sites was low. For all sites, a total of 1,324 species were recorded, of which 342 were unique to veredas and 187 unique to moist grasslands (campos limpos úmidos. After reviewing databases, 14.3 % of these species remained exclusive to veredas and moist grasslands. The ordination analysis indicated a gradient in floristic composition from wet to dry phytophysiognomies. In conclusion, we recognize a flora that distinguishes veredas from other Cerrado phytophysiognomies.

Proteomic analysis of three gonad types of swamp eel reveals genes differentially expressed during sex reversal.

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Sheng, Yue; Zhao, Wei; Song, Ying; Li, Zhigang; Luo, Majing; Lei, Quan; Cheng, Hanhua; Zhou, Rongjia

2015-05-18

A variety of mechanisms are engaged in sex determination in vertebrates. The teleost fish swamp eel undergoes sex reversal naturally and is an ideal model for vertebrate sexual development. However, the importance of proteome-wide scanning for gonad reversal was not previously determined. We report a 2-D electrophoresis analysis of three gonad types of proteomes during sex reversal. MS/MS analysis revealed a group of differentially expressed proteins during ovary to ovotestis to testis transformation. Cbx3 is up-regulated during gonad reversal and is likely to have a role in spermatogenesis. Rab37 is down-regulated during the reversal and is mainly associated with oogenesis. Both Cbx3 and Rab37 are linked up in a protein network. These datasets in gonadal proteomes provide a new resource for further studies in gonadal development.

On the relative roles of hydrology, salinity, temperature, and root productivity in controlling soil respiration from coastal swamps (freshwater)

Science.gov (United States)

Krauss, Ken W.; Whitbeck, Julie L.; Howard, Rebecca J.

2012-01-01

Background and aims Soil CO2 emissions can dominate gaseous carbon losses from forested wetlands (swamps), especially those positioned in coastal environments. Understanding the varied roles of hydroperiod, salinity, temperature, and root productivity on soil respiration is important in discerning how carbon balances may shift as freshwater swamps retreat inland with sea-level rise and salinity incursion, and convert to mixed communities with marsh plants. Methods We exposed soil mesocosms to combinations of permanent flooding, tide, and salinity, and tracked soil respiration over 2 1/2 growing seasons. We also related these measurements to rates from field sites along the lower Savannah River, Georgia, USA. Soil temperature and root productivity were assessed simultaneously for both experiments. Results Soil respiration from mesocosms (22.7-1678.2 mg CO2 m-2 h-1) differed significantly among treatments during four of the seven sampling intervals, where permanently flooded treatments contributed to low rates of soil respiration and tidally flooded treatments sometimes contributed to higher rates. Permanent flooding reduced the overall capacity for soil respiration as soils warmed. Salinity did reduce soil respiration at times in tidal treatments, indicating that salinity may affect the amount of CO2 respired with tide more strongly than under permanent flooding. However, soil respiration related greatest to root biomass (mesocosm) and standing root length (field); any stress reducing root productivity (incl. salinity and permanent flooding) therefore reduces soil respiration. Conclusions Overall, we hypothesized a stronger, direct role for salinity on soil respiration, and found that salinity effects were being masked by varied capacities for increases in respiration with soil warming as dictated by hydrology, and the indirect influence that salinity can have on plant productivity.

Assessment of semen quality in Swamp Buffalo AI Bulls in Thailand

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S. Koonjaenak

2010-02-01

Full Text Available Characteristic of Thai swamp buffalo bulls semen used for artificial insemination (AI in Thailand, aspects relevance in freezing and thawing of semen are review. Semen and sperm characteristics were evaluated included sperm count, motility (assessed subjectively and by CASA, morphology (using phase-contrast light microscopy and SEM, plasma membrane integrity (PMI (using a hypo-osmotic swelling test [HOST] and SYBR- 14/propidium iodide [PI], plasma membrane stability (PMS (using Annexin-V/PI and deoxyribonucleic acid (DNA integrity (using SCSA and flow cytometry [FCM]. The average ejaculate volume was about 3.0–4.0 mL, with good viability (PMI measured by the HOST and motility (>65% and >70%, respectively. Sperm concentration ranged from 1.1 to 1.2 billion/mL, being also affected by bull age. Whereas semen quality (including sperm output, pH and initial sperm motility did not differ between the seasons. Few spermatozoa (<15%/ ejaculate had abnormal morphology with abnormalities resembling those in other bovidae. In FT semen, PMI (using SYBR-14/PI and PMS were highest in winter. Across seasons, ~50% of post-thaw spermatozoa depicted linear motility, a proportion that decreased to ~35% during incubation (38oC for 60 minutes, without marking any seasonal difference. The sperm DNA was hardly damaged (with <3% fragmentation, expressed as DNA fragmentation index [DFI], among seasons.

Calculation method for determination of carbon in the peatand moss litter of forest swamps by ash content of plant substrates

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T. T. Efremova

2016-12-01

Full Text Available Studies were carried out in the lowmountain part of the Kuznetsk Alatau. The spruce stands were studied in the peaty valley of river Tunguzhul and swamp near Agaskyr Lake (valley of river Pechische, basin of river Black Iyus. The objects belong to the group of high ash content flood plain peat lands of cryogenicseries. We have done the evaluation of organic carbon response to physical-chemical properties – decomposition degree, ash content, and bulk density, connected together (r – 0.5–0.7, that in contrast to carbon, is easy determined analytically. Received results according to stepwise regression analysis characterize the strong conditionality predictors of carbon: multiple determination index R2 – 0.86. The highest partial correlation coefficient with the response belongs to the ash content in range (5–68 %. Partial correlation coefficient values of bulk density and decomposition degree is not significant. The determination index (R2 – 0.93, constant and negative coefficient of pair regression analysis are highly significant and evidence of the strong bond of carbon and organic substrate ash content. The relative error of approximation is in the range of 2–8 % and characterizes the high accuracy of prognosis. Including only one indicator (ash content in the calculation formula makes it convenient and simple in practical application for the carbon content prediction on the forest litter, modern peat soils, buried peat and peat-mineral formations with ash content of 5–68 %. We are the first to present the geochemical characteristics of forest swamps peat mine for the KuznetskAlatau intermountain basins.

Monticellia ophisterni n. sp. (Cestoda: Monticelliidae) from the swamp-eel Ophisternon aenigmaticum (Synbranchiformes) from Mexico.

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Scholz, T; de Chambrier, A; Salgado-Maldonado, G

2001-12-01

Monticellia ophisterni n. sp. is described from the swamp-eel Ophisternon aenigmaticum Rosen and Greenwood (Synbranchiformes: Synbranchidae) from Lake Catemaco, Veracruz, Mexico. The new species is placed into Monticellia because of the cortical position of the testes, ovary, and uterus. It differs from other Monticellia species (with the exception of Monticellia magna (Rego, Santos and Silva, 1974)) in the position of longitudinal musculature that crosses the vitelline follicles, making them paramuscular. The new species can be distinguished from M. magna--which possesses a similar number of testes (107-139), paramuscular vitelline follicles, and numerous gland cells distributed between the apex of the scolex and suckers--in the position of the genital pore (8-21% vs. 19-27%), in the presence of a weak internal longitudinal musculature, in the arrangement of the testes in the median field, and in the absence of a vaginal sphincter. This is the first proteocephalidean tapeworm reported from a synbranchid fish and the first species of Monticellia found in North America.

DNA-based hair sampling to identify road crossings and estimate population size of black bears in Great Dismal Swamp National Wildlife Refuge, Virginia

OpenAIRE

Wills, Johnny

2008-01-01

The planned widening of U.S. Highway 17 along the east boundary of Great Dismal Swamp National Wildlife Refuge (GDSNWR) and a lack of knowledge about the refugeâ s bear population created the need to identify potential sites for wildlife crossings and estimate the size of the refugeâ s bear population. I collected black bear hair in order to collect DNA samples to estimate population size, density, and sex ratio, and determine road crossing locations for black bears (Ursus americanus) in G...

Draining the swamp while making America great: senior dissonance in the age of Trump.

Science.gov (United States)

Hudson, Robert B

2018-04-13

In his surprise election as President, Donald Trump enjoyed disproportionate electoral support from older voters, many of whom saw in Trump a person who would work to reverse demographic, economic, and cultural forces that had transformed American life as they had long seen it. Yet, Trump's campaign and incumbency has also been very much about gutting the Washington policy establishment of officials, bureaucrats, and lobbyists (aka, the Swamp) which, for over half a century, has been instrumental in enacting and expanding legislation that has benefitted older Americans, far more than any other social policy constituency in the country. This article contrasts the value-oriented electoral support Trump enjoyed from older Americans with their interest concerns centered on policies such as the Affordable Care Act, Medicaid, and a host of smaller grant-in-aid programs. It then reviews the strong institutional base seniors and their advocates have in Washington, posing whether interest-oriented concerns may outweigh ideological ones as policy options emerge from a Republican-controlled government prior to the 2018 elections.

Performans Produksi, Jumlah Nematoda Usus, dan Profil Metabolik Darah Kambing yang Diberi Pakan Hijauan Rawa Kalimantan (PRODUCTION PERFORMANS, INTESTINE NEMATODE NUMBER AND METABOLIC BLOOD PROFILE OF GOAT FEED WITH BORNEO SWAMP FORAGE

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Tintin Rostini

2017-09-01

Full Text Available This study aims were to determine the effect of the use of swamp forage on the performances, the number of nematodes and the blood metabolic profile in goats. In this study, as many as 24 male goats were used; consisted of 12 local male goats (kacang goat with the average weight ranged from 12.65±1.65kg (diversity coefficient 11.34% and 12 PE goats with the average weight of 18.05±0.62 kg (diversity coefficient 7.54%. This research used a completely randomized factorial design (CRD 2x4 with 2 main treatments x 4 factorials and three replications. The first factor was based on the goat breed being used (Kacang and Peranakan Etawah. The second factor was based on four differents feed percentages that used, i.e.: (PR0 40% grass forage and 60% concentrate, (PR1 60% grass forage and 40% concentrate, (PR2, 40% of swamp forage and concentrates 60%, (PR3 60% swamp forage and 40% concentrate. Data were analyzed by using analysis of variance, then continued with Duncan test. The results of this study showed that the consumption of nutrients, daily weight gain and feed efficiency in treatment provision of swamp forage up to 60% (PR3 gave best result based on the metabolic profile of blood (total protein, glucose, cholesterol, Ca and P. The number of worm eggs in the goat feces were still in normal range. It was concluded that swamp forage is a potential forage that can be used as an alternative towards grass forage for the goats. ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan hijauan rawa terhadap performans, jumlah nematoda, dan profil metabolik darah kambing. Pada penelitian ini digunakan ternak kambing jantan sebanyak 24 ekor. Kambing yang digunakan terdiri dari 12 ekor kambing kacang jantan dengan rataan bobot badan berkisar antara 12,65 ± 1,65 kg (koefisien keragaman 11,34% dan 12 ekor kambing peranakan etawah (PE dengan rataan bobot badan 18,05 ± 0,62 kg (koefisien keragaman 7,54%. Dalam penelitian ini digunakan rancangan

The Munchausen paradigm for deprived neighbourhoods: pulling yourself out of the swamp of deprivation

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Jeannette Nijkamp

2017-06-01

Full Text Available The Munchausen paradigm for deprived neighbourhoods: pulling yourself out of the swamp of deprivation Since the 1980s, many initiatives have attempted to tackle the deprivation currently experienced in South Rotterdam. Efforts have been made to attract creative workers and, in a counter-reaction, other initiatives have aimed to encourage the creative talents of poorer residents to strengthen their economic position. One example of this is Freehouse, which has established projects in the Afrikaanderwijk, including a neighbourhood cooperative. Our article addresses two questions: 1 What are the effects of the Freehouse projects on the economic position of residents of the Afrikaanderwijk? and 2 Which insights do our results provide into the possible effects of local government policies that rely on citizens playing an active role? Although the economic effects of the projects were limited, our study reveals that citizens’ initiatives, such as the Afrikaander Cooperative, can help residents gain employment. In order to succeed, these initiatives should not be hindered by obstructive regulations, and they should include input from the residents who function as staff. However, in deprived neighbourhoods, many residents require support to be able to contribute to citizens’ initiatives, and cannot be expected to act like Baron Münchausen and pull themselves out of the swamp of deprivation by their own hair. Het Münchausen paradigma voor achterstandswijken: jezelf uit het moeras van achterstand trekken Sinds de jaren 80 hebben veel initiatieven geprobeerd het achterstandsniveau in Rotterdam Zuid te verminderen. Verschillende initiatieven waren gericht op het aantrekken van creatieve professionals. Als tegenreactie stimuleerden andere initiatieven de creatieve talenten van arme wijkbewoners teneinde hun economische positie te versterken. Een voorbeeld hiervan is Freehouse, dat projecten in de Afrikaanderwijk startte, waaronder de oprichting van

Effect of Ground Corn Cob Replacement for Cassava Chip on Feed Intake, Rumen Fermentation and Urinary Derivatives in Swamp Buffaloes

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M. Wanapat

2012-08-01

Full Text Available Four Thai - rumen fistulated male swamp buffaloes (Bubalus bubalis, about four years old with 400±20 kg liveweight, were randomly assigned according to a 4×4 Latin square design to receive dietary treatments. The treatments were: ground corn cob (GCC replacement for cassava chip (CC in concentrate at 0% (T1; GCC replacement at 33% (T2; GCC replacement at 67% (T3; and GCC replacement at 100% (T4, respectively. During the experiment, concentrate was offered at 0.5% BW while 5% urea-treated rice straw was given at ad libitum. The result revealed that there was no effect of GCC replacement on DMI among treatments. In addition, digestibilities of DM, OM and CP were not different while aNDF linearly increased with an increasing level of GCC replacement. However, GCC replacement did not affect rumen fermentation such as ruminal pH, NH3-N and VFA concentration; except C3 proportion which was the highest at 33% replacement while the lowest was at 100% replacement. All replacements of GCC resulted in similar protozoal and bacterial populations and microbial protein synthesis (MPS. Purine derivatives (PD concentration in urine and PD to creatinine (PDC index were varied with time of urination and among treatments at 0 to 8 and 8 to 16 h post feeding and higher values were shown among the GCC replacement groups. However at 16 to 24 h-post feeding, it was untraceable. In addition, creatinine concentration was similar among all treatments at every sampling time. Based on the above results, GCC can be used as an energy source for swamp buffalo fed with rice straw. Spot sampling of urine can be used for purine derivatives determination.

Yolk proteins during ovary and egg development of mature female freshwater crayfish (Cherax quadricarinatus).

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Serrano-Pinto, Vania; Vazquez-Boucard, Celia; Villarreal-Colmenares, Humberto

2003-01-01

Vitellins from ovaries and eggs at different stages of development in freshwater crayfish (Cherax quadricarinatus) were examined by chromatography, PAGE and SDS-PAGE. With these methods, two forms of vitellin (Vt1 and Vt2) were observed in ovaries and eggs (stages I and V). In ovaries in secondary vitellogenesis, native molecular mass was 470 (Vt1) and 440 (Vt2) kDa. The electrophoretic pattern of the eggs proved to be more complex. The protein molecular mass depend on the development stage of the egg: stage I, 650 kDa (Vt1) and 440 kDa (Vt2); stage V, 390 kDa (Vt1) and 340 kDa (Vt2). The identified vitellins appear to be lipo-glycocarotenoprotein. A similar vitellin polypeptide composition was observed in the two forms of vitellin from ovaries and eggs in stage V. In ovaries the SDS-PAGE analysis showed four subunits with molecular weights of approximately 180, 120, 95 and 80 kDa (Vt1 and Vt2). The polypeptide composition in the two forms of vitellins in stage I and stage III eggs were different at 195, 190, 130 and 110 kDa (Vt1) and 116 and 107 kDa (Vt2). On the other hand, in stage V eggs, 110, 95, 87 and 75 kDa (Vt1 and Vt2) were identified. Two antibodies (Ab1 and Ab2) were prepared against the purified proteins of stage V eggs and their specificity was demonstrated by radial immunoprecipitation, and Western blotting analysis. Two forms of vitellins were also found in stage V eggs after chromatography on Sepharose CL-2B column and hydroxylapatite and polyacrylamide gel electrophoresis.

BIOLOGICAL WATER QUALITY ASSESSMENT OF THE WHITECLAWED CRAYFISH HABITAT BASED ON MACROINVERTEBRATE COMMUNITIES: USEFULNESS FOR ITS CONSERVATION

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GRANDJEAN F.

2003-04-01

Full Text Available A survey of the macroinvertebrates of three brooks harbouring the white-clawed crayfish was conducted in Haute-Vienne department (France. Its aim was to increase our understanding of these ecosystems to help the conservation of A. pallipes. These brooks run through pastoral areas with well-developed riparian vegetation, which offers an important shade. Water temperature, dissolved oxygen concentration, pH, and conductivity fell within the ranges found for this species. A total of 34, 31, 29 taxa and 1 502, 1 364, 2 707 individuals of macrobenthos were collected in Holme, Besque and Bellecombe streams, respectively. Results showed good to very good water quality with IBGN scores ranging from 15 (Bellecombe to 17 (Holme and Besque, reflecting a limited impact of the anthropogenic disturbances. Taxa diversity were high for Holme and Besque with Shannon index around 3.2, translating a great heterogeneity of habitat and an equilibrated faunal community. Bellecombe showed a limited diversity with Shannon index of 1.42, resulting from the presence of numberous Chironomidae. This brook suffers probably weak organic pollution which could be related to the low water flow observed during the sampling. The similarity test according to Jaccard index showed high percentage of common taxa among ETP (Ephemeroptera-Trichoptera-Plecoptera between all sites. The high similarity of benthic macroinvertebrate communities could be an useful criteria to identify brooks for restocking purpose.

Ultrastructural observations of target-organs of the crayfish Orconectes limosus exposed to metallic pollutants: application to uranium

International Nuclear Information System (INIS)

Grasset, G.; Simon, O.; Floriani, M.

2004-01-01

Using electron microscopy associated with energy dispersive X-ray microanalysis (EDAXTEM), ultrastructure and elemental analysis in subcellular micro-localization can bring understanding to both metabolic cycle of a metallic pollutant and its potential effects at the subcellular scale. The approach consists in comparing both structures and micro-localization in various tissues/organs ultrathin sections (70-140 nm thickness) obtained from control organisms (i.e. not exposed to a given metal) and exposed organisms. However, the observations of ultrastructural effects of metal exposure involved robust comparison to reference subcellular and cellular organization. Consequently, preliminary developments presented in this poster have been performed from the non-contaminated freshwater crayfish Orconectes limosus (adult at inter-moult state). Studies of ultrastructural images and elemental composition of subcellular mineral deposits were carried out on target organs of uranium accumulation such as the digestive gland, the gills, the intestine and the antennal gland, organs participating in the detoxification, primary accumulation and depuration mechanisms. Observations indicated cell-specific architecture (identification of main organelles, frequency, length of cells), the range of natural variation of the cell organisation between individuals and identification of cellular types. Information will allow then to focus on these identified specific organization after metallic exposure. These ultrastructural observations performed on reference organisms constitute necessarily a first set of data for the cellular metallic effects analysis. (author)

Determination of endocrine patterns and their applications in the swamp buffalo

International Nuclear Information System (INIS)

Kamonpatana, M.

1984-01-01

The introduction of AI in swamp buffalo breeding has made hormonal measurement and treatment an important area of research. Hormonal regulation of buffalo reproduction is becoming an increasingly important tool for monitoring genetic progress and productivity. The development of immunoassay techniques for measuring progesterone was quickly identified as a suitable tool for monitoring the reproductive status of the water buffalo. Progesterone profiles during the oestrous cycle, pregnancy, parturition and post partum have been established. A knowledge of progesterone levels has helped to improve clinical skills in determining reproductive status. Attempts have been made to understand the role of gonadotrophins during these reproductive stages, to advance the onset of postpartum cyclicity, and to characterize the weak signs of oestrus. Peripartal changes of oestrone and prostaglandin have been monitored. Endocrinological methods for oestrus synchronization have been developed and applied and oestrone sulphate and progesterone have been used to assess pregnancy status and a rapid pregnancy test has been utilized to maximize reproductive efficiency in ranch-type breeding herds. In the male attempts have been made to clarify the testicular testosterone secretory capacity and the possible relationships between testosterone secretion, libido, semen characteristics and the influence of season. Within the context of long-term improvement, these studies should help to decrease calving intervals, improve heat and non-pregnancy detection, and allow for subfertility discrimination and sire selection with consequent increases in milk and meat production and draught power. (author)

AN INVESTIGATION INTO THE DISAPPEARANCE OF AUSTROPOTAMOBIUS PALLIPES (LEREBOULLET POPULATIONS IN THE HEADWATERS OF THE NORE RIVER, IRELAND AND THE CORRELATION TO WATER QUALITY

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LYONS R.

2003-04-01

Full Text Available Monitoring of the protected white-clawed crayfish Austropotamobius pallipes (Lereboullet has been carried out in the headwaters of the Nore River since 1995. In recent years a reduction in crayfish abundance had become apparent. Some populations had completely disappeared. Adult crayfish were sampled using the baited trap method while juveniles were sampled using a modified surber sampler. The temporal variation in baited trap data was found to be significant at three of the sites while significant variation in enclosure sampling data was found at two sites. In an effort to ascertain why the populations had disappeared a possible relationship between water quality and adult and juvenile crayfish numbers was investigated. Water quality was assessed using both chemical and macroinvertebrate data. Macroinvertebrate sampling revealed deterioration in water quality at all sites. Results also showed the disappearance of crayfish from both Q3 and Q3-4 waters at some sites yet crayfish remain at these Q-ratings at other sites. Therefore the Q-rating below which crayfish cannot survive cannot clearly be defined. However, no clear correlation was observed between the water chemistry data and the crayfish data. Crayfish populations at the Fertagh (FRT site appear to be surviving intermittent pollution and eutrophic conditions where pre-dawn oxygen sags reach lows of 4.4 mg/l O2. Deterioration in water quality as indicated by the Q-value biotic index coincided with reduced crayfish catches. There is no evidence to suggest that predation be it of aquatic or terrestrial origin is a major contributing factor.

The effect of mixed liming and NPK fertilizer to yield of some rice varieties on new openings of acid sulfate tidal swamp land

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Akhmad, A.; Dewi, W. S.; Sagiman, S.; Suntoro

2018-03-01

The strategies to meet the staple food needs in Indonesia is to open new paddy fields in the sub-optimal land. The research aims to get adaptive rice varieties with the highest yield on new openings of the acid sulfate tidal swamp applying mixed liming and NPK fertilizer. The experiment was conducted in a greenhouse at the Faculty of Agriculture, Tanjungpura University, Pontianak. The trials used a factorial completely randomized block design consisting of two factors. The first factor is a mixture of dolomite with NPK fertilizer, consisting of 3 levels (1 ton/ha dolomite and 60 kg/ha NPK; 2 ton/ha dolomite and 90 kg/ha of NPK, and 3 ton/ha dolomite and 120 kg/ha NPK). The second factor is rice varieties, consisting of 6 levels (Ciherang, Situ Bagendit, Inpara, Mira, Si Randah and Ringkak Janggut). Each treatment replicated four times. The results showed that the application of a mixture of 3 ton/ha dolomite and 120 kg/ha of NPK fertilizer showed the best results to improve rice yield on new opening of the acid sulfate tidal swap. Local rice varieties, Ringkak Janggut, applied 3 ton/ha dolomite and 120 kg/ha NPK fertilizer showed the best result of 1000 seed weight, i.e., 28.19 g, and total grain amount per panicle is 110.75 grains, with the lowest number of empty grains. Local rice varieties Ringkak Janggut potential to be developed as superior varieties on new opening acid sulfate tidal swamps by applying liming and fertilizer.

Aquatic macroinvertebrate responses to native and non-native predators

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Haddaway N. R.

2014-01-01

Full Text Available Non-native species can profoundly affect native ecosystems through trophic interactions with native species. Native prey may respond differently to non-native versus native predators since they lack prior experience. Here we investigate antipredator responses of two common freshwater macroinvertebrates, Gammarus pulex and Potamopyrgus jenkinsi, to olfactory cues from three predators; sympatric native fish (Gasterosteus aculeatus, sympatric native crayfish (Austropotamobius pallipes, and novel invasive crayfish (Pacifastacus leniusculus. G. pulex responded differently to fish and crayfish; showing enhanced locomotion in response to fish, but a preference for the dark over the light in response to the crayfish. P.jenkinsi showed increased vertical migration in response to all three predator cues relative to controls. These different responses to fish and crayfish are hypothesised to reflect the predators’ differing predation types; benthic for crayfish and pelagic for fish. However, we found no difference in response to native versus invasive crayfish, indicating that prey naiveté is unlikely to drive the impacts of invasive crayfish. The Predator Recognition Continuum Hypothesis proposes that benefits of generalisable predator recognition outweigh costs when predators are diverse. Generalised responses of prey as observed here will be adaptive in the presence of an invader, and may reduce novel predators’ potential impacts.

Proteomic analysis of the crayfish gastrolith chitinous extracellular matrix reveals putative protein complexes and a central role for GAP 65.

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Glazer, Lilah; Roth, Ziv; Weil, Simy; Aflalo, Eliahu D; Khalaila, Isam; Sagi, Amir

2015-10-14

Chitin is a major component of arthropod cuticles, where it forms a three-dimensional network that constitutes the scaffold upon which cuticles form. The chitin fibers that form this network are closely associated with specific structural proteins, while the cuticular matrix contains many additional structural, enzymatic and other proteins. We study the crayfish gastrolith as a simple model for the assembly of calcified cuticular structures, with particular focus on the proteins involved in this process. The present study integrates a gastrolith-forming epithelium transcriptomic library with data from mass spectrometry analysis of proteins extracted from the gastrolith matrix to obtain a near-complete picture of gastrolith protein content. Using native protein separation we identified 24 matrix proteins, of which 14 are novel. Further analysis led to discovery of three putative protein complexes, all containing GAP 65 the most abundant gastrolith structural protein. Using immunological methods we further studied the role of GAP 65 in the gastrolith matrix and forming epithelium, as well as in the newly identified protein complexes. We propose that gastrolith matrix construction is a sequential process in which protein complexes are dynamically assembled and disassembled around GAP 65, thus changing their functional properties to perform each step in the construction process. The scientific interest on which this study is based arises from three main features of gastroliths: (1) Gastroliths possess partial analogy to cuticles both in structural and molecular properties, and may be regarded, with the appropriate reservations (see Introduction), as simple models for cuticle assembly. At the same time, gastroliths are terminally assembled during a well-defined period, which can be controlled in the laboratory, making them significantly easier to study than cuticles. (2) Gastroliths, like the crayfish exoskeleton, contain stable amorphous calcium carbonate (ACC) rather

The burrows of Parastacus defossus (Decapoda: Parastacidae, a fossorial freshwater crayfish from southern Brazil

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Clarissa K. Noro

2010-06-01

Full Text Available Parastacus defossus Faxon, 1898 is a fossorial crayfish species, which constructs its burrows in swampy areas in southeast Uruguay and in the state of Rio Grande do Sul, Brazil. The present field study was carried out in Lami, Porto Alegre, Rio Grande do Sul, Brazil, from May 2003 through August 2005. Environmental measurements (temperature, pH, dissolved oxygen, and water-table depth of the water in the galleries were made monthly. Burrow morphology was analyzed by means of resin and gypsum casts. The spatial distribution and changes in the number and shape of the surface openings over time were observed in a 100 m² area. To estimate the spatial distribution of the openings, the observed distribution was compared with the expected distribution predicted by the Poisson and Negative Binomial frequency-distribution models. The adult population density was estimated by direct observation of burrows and counts in the study area. Inside the burrows of P. defossus, the water temperature ranged between 16.6°C (autumn 2004 and 23°C (spring 2003. The water was hypoxic and slightly acidic, and the dissolved oxygen content was very low (mean 1.43 mg/l (18.2% saturation. The soil with burrows had higher percentages of coarse sand, fine sand, and silt. The spatial distribution of the openings showed a significant fit to the Negative Binomial distribution, indicating that the distribution of the openings is aggregated, as confirmed from the burrow morphology. The galleries are always formed by a central tunnel with multiple branchings that connect the underground water to the soil surface by one or more openings, which can be recognized by the chimneys. From knowledge of the burrow morphology, the population density was estimated to be about 120 individuals/100 m².

PENGEMBANGAN KONSEP AGROINDUSTRI BERBASIS SISTEM USAHATANI TERPADU DI WILAYAH PASANG SURUT BAGIAN I: (KONSEP PEMIKIRAN The Concept Development of Agroindustry Based on Integrated Farming System at Tidal Swamp Land Areas Chapter I: Conceptual Thinkin

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Rustan Massinai

2013-06-01

Full Text Available Integrated farming system was directed in efforts to lengthen biological cycle by optimizing use of agriculture and livestock products. Each chain of cycle resulted new product that have high economic value, so this system was expected to optimize empowerment and use of marginal land in all regions. The problems encountered in agricultural systems in tidal swamp land in general, i.e; (a limitations in the form of land, human resources, technology, and capital owned by farmers, then the potential of local resources need to be managed optimally, directed, integrated and sustainable with a view to improve land productivity and living standards of farmers by way of application of integrated farming systems by integrating crop and livestock based on the potential of local areas, and (b socio-economic problems and constraints in the development of food crops was due to a swamp area. The objective of this research was to produce integrated farming system concept to support agroindustry development in tidal swamp land in Pulang Pisau regency of Central Kalimantan province. This research was conducted with a book study method, which identifies a system consisting of integrated farming and agroindustry systems. In the both identification is performed by the system includes four aspects, i,e; economic aspects, technical aspects, social aspects of cultural and environmental. Integrated farming systems concept in tidal swamp land was generated from the production of integrated farming systems should first be processed through the processing system (agroindustry in the form of home industry, or using a mechanical device. After that, it was carried out the marketing of products, systems concepts was expected to increase the added value of agricultural production (rice, coffee and cow. With the application of agroindustry systems in tidal swamp land Pulang Pisau regency of Central Kalimantan Province is expected to increase the economic income of farmers in

Heavy Metals Bioaccumulation in Tissues of Spiny-Cheek Crayfish (Orconectes limosus) from Lake Gopło: Effect of Age and Sex.

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Stanek, Magdalena; Dąbrowski, Janusz; Różański, Szymon; Janicki, Bogdan; Długosz, Jacek

2017-06-01

The aim of the present work was to assess the concentrations of metals in the abdominal muscle and exoskeleton of 3-year-old males and 4-year-old females and males of spiny-cheek crayfish (Orconectes limosus) collected from Lake Gopło. A total of 93 males and 35 females were collected in autumn (October 2014). The analyzes of heavy metals were conducted by means of atomic absorption spectroscopy with a PU9100X spectrometer. The content of mercury was determined using AMA 254 mercury analyser. As analyses indicated heavy metals accumulated in the muscle and exoskeleton in the following sequence: Zn > Cu > Pb > Mn > Ni > Hg and Mn > Pb > Zn > Ni > Cu > Hg, respectively. Statistically significant differences between 3- and 4-year-old males were found for all analyzed metals. Gender dependent differences were calculated only for Ni in the muscle tissue and for Mn and Hg in the exoskeleton. In comparison with the study carried out 2 years ago notably higher concentrations of Pb were found in the muscle and a higher content of Zn, Pb, Mn and Ni was determined in the exoskeleton.

Vegetation change in the coastal-lowland rainforest at Avai'o'vuna Swamp, Vava'u, Kingdom of Tonga

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Fall, Patricia L.

2005-11-01

Avai'o'vuna Swamp, a small coastal wetland in Vava'u, Kingdom of Tonga, produced a 4500-year pollen and sediment record. Results are: (1) a mid-Holocene sea level highstand is confirmed for Tonga between about 4500 and 2600 14C yr B.P.; marine clay contains pollen from mangroves ( Rhizophora mangle), coastal forest trees ( Barringtonia asiatica and Cocos nucifera), and rainforest trees ( Alphitonia, Rhus, Hedycarya and Calophyllum). (2) Microscopic charcoal first appeared at 2600 14C yr B.P., coincident with the arrival of Polynesians. (3) Cocos, Pandanus, Excoecaria, Macaranga, and Elaeocarpaceae pollen reflects the establishment of a mixed coastal-lowland rainforest in the last 2500 years. (4) The loss of Hedycarya, Elaeocarpus, Calophyllum, and Guettarda and the reduction of Terminalia and taxa in the Papilionaceae family by about 1000 years ago may be due to habitat destruction and the loss of dispersal capabilities of some species through the extinction of the two largest pigeons in Tonga.

Evaluation of solid residues removed from a mangrove swamp in the São Vicente Estuary, SP, Brazil.

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Cordeiro, C A M M; Costa, T M

2010-10-01

Mangrove swamps are found in estuaries along the coastal plains of tropical regions and have be subjected to heavy occupation and use pressure due to their privileged locations and abundance of biological resources. The present work evaluated the ecological characteristics and solid wastes accumulated in eight areas along the Santos - São Vicente Estuary Complex. The superficially deposited residues at each sampling site were collected and subsequently washed, drained, counted, weighed and separated into classes according to their composition and predominant use. The predominant litter type in terms of density was plastic (62.81%) and, by weight, wood (55.53%). The greatest deposition of residues was associated with areas that were less inclined and that had low plant density levels, indicating that the presence of obstacles was not critical for retaining floating residues in mangrove areas. The presence of the most frequently encountered types of solid waste residues could be explained by local activities. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effects of fires on the chemical and petrographic composition of peat in the Snuggedy Swamp, South Carolina

Energy Technology Data Exchange (ETDEWEB)

Rollins, M S; Cohen, A D; Durig, J R [South Carolina University, Columbia, SC (USA). Dept. of Chemistry

1993-04-01

Charcoal-rich zones in a peat core from the Snuggedy Swamp in South Carolina were investigated to determine the chemical and physical changes associated with fires. Petrographic analyses of microtome thin sections revealed that three charcoal zones were present in the core and that the fires causing such zones were severe enough to penetrate into the subsurface and burn some of the peat. Despite these severe fires, only minor changes in the botanical composition occurred throughout the history of the study site, suggesting that these fires were not extensive enough to retard recolonization of the site from nearby unburned areas. Pyrolysis gas chromatography/Fourier transform infrared/flame ionization detection and pyrolysis gas chromatography/mass spectrometry studies reveal distinct organic chemical changes in the peat that can be related to the fires. Decreases in aliphatic and cellulose compounds mirrored increases in charcoal abundance; while aromatic, lignin-related compounds increased as charcoal increased. 44 refs., 8 figs., 1 tab.

Dispositions of enrofloxacin and its major metabolite ciprofloxacin in Thai swamp buffaloes

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RUENNARONG, Nitwarat; WONGPANIT, Kannika; SAKULTHAEW, Chainarong; GIORGI, Mario; KUMAGAI, Susumu; POAPOLATHEP, Amnart; POAPOLATHEP, Saranya

2015-01-01

Given the limited information available in this species, the aim of this study was to investigate the pharmacokinetic characteristics of enrofloxacin (ER) and its major metabolite ciprofloxacin (CP) in buffaloes, Bubalus bubalis. ER was administered intravenously (i.v.) or subcutaneously (s.c.) to buffaloes at doses of 5.0 and 7.5 mg/kg BW, and plasma, urine and fecal samples were collected until 48 hr post-administration. The concentrations of ER and CP in the plasma, urine and feces were analyzed using high-performance liquid chromatography equipped with a fluorescence detector. The plasma concentrations of ER and CP could be determined up to 24 hr and 32 hr after i.v. and s.c. administrations at doses of 5.0 and 7.5 mg/kg BW, respectively. CP concentrations were always lower than those of parental drug. The s.c. bioavailability of ER was 52.36 ± 4.24% and 72.12 ± 5.39% at doses of 5.0 and 7.5 mg/kg BW, respectively. Both ER and CP were detectable in urine and feces up to 24 hr. ER and CP were mainly excreted via the urine. Based on the pharmacokinetic data and PK-PD indices, s.c. administration of ER at doses of 5.0 and 7.5 mg/kg BW might be appropriate for the treatment of susceptible bacterial diseases in Thai swamp buffaloes. PMID:26596287

Deforestation projections for carbon-rich peat swamp forests of Central Kalimantan, Indonesia.

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Fuller, Douglas O; Hardiono, Martin; Meijaard, Erik

2011-09-01

We evaluated three spatially explicit land use and cover change (LUCC) models to project deforestation from 2005-2020 in the carbon-rich peat swamp forests (PSF) of Central Kalimantan, Indonesia. Such models are increasingly used to evaluate the impact of deforestation on carbon fluxes between the biosphere and the atmosphere. We considered both business-as-usual (BAU) and a forest protection scenario to evaluate each model's accuracy, sensitivity, and total projected deforestation and landscape-level fragmentation patterns. The three models, Dinamica EGO (DE), GEOMOD and the Land Change Modeler (LCM), projected similar total deforestation amounts by 2020 with a mean of 1.01 million ha (Mha) and standard deviation of 0.17 Mha. The inclusion of a 0.54 Mha strict protected area in the LCM simulations reduced projected loss to 0.77 Mha over 15 years. Calibrated parameterizations of the models using nearly identical input drivers produced very different landscape properties, as measured by the number of forest patches, mean patch area, contagion, and Euclidean nearest neighbor determined using Fragstats software. The average BAU outputs of the models suggests that Central Kalimantan may lose slightly less than half (45.1%) of its 2005 PSF by 2020 if measures are not taken to reduce deforestation there. The relatively small reduction of 0.24 Mha in deforestation found in the 0.54 Mha protection scenario suggests that these models can identify potential leakage effects in which deforestation is forced to occur elsewhere in response to a policy intervention.

Swamp Works: A New Approach to Develop Space Mining and Resource Extraction Technologies at the National Aeronautics Space Administration (NASA) Kennedy Space Center (KSC)

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Mueller, R. P.; Sibille, L.; Leucht, K.; Smith, J. D.; Townsend, I. I.; Nick, A. J.; Schuler, J. M.

2015-01-01

The first steps for In Situ Resource Utilization (ISRU) on target bodies such as the Moon, Mars and Near Earth Asteroids (NEA), and even comets, involve the same sequence of steps as in the terrestrial mining of resources. First exploration including prospecting must occur, and then the resource must be acquired through excavation methods if it is of value. Subsequently a load, haul and dump sequence of events occurs, followed by processing of the resource in an ISRU plant, to produce useful commodities. While these technologies and related supporting operations are mature in terrestrial applications, they will be different in space since the environment and indigenous materials are different than on Earth. In addition, the equipment must be highly automated, since for the majority of the production cycle time, there will be no humans present to assist or intervene. This space mining equipment must withstand a harsh environment which includes vacuum, radical temperature swing cycles, highly abrasive lofted dust, electrostatic effects, van der Waals forces effects, galactic cosmic radiation, solar particle events, high thermal gradients when spanning sunlight terminators, steep slopes into craters / lava tubes and cryogenic temperatures as low as 40 K in permanently shadowed regions. In addition the equipment must be tele-operated from Earth or a local base where the crew is sheltered. If the tele-operation occurs from Earth then significant communications latency effects mandate the use of autonomous control systems in the mining equipment. While this is an extremely challenging engineering design scenario, it is also an opportunity, since the technologies developed in this endeavor could be used in the next generations of terrestrial mining equipment, in order to mine deeper, safer, more economical and with a higher degree of flexibility. New space technologies could precipitate new mining solutions here on Earth. The NASA KSC Swamp Works is an innovation

Impact of logging on a mangrove swamp in South Mexico: cost / benefit analysis

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Cristian Tovilla Hernández

2001-06-01

Full Text Available Environmental changes caused by logging in a mangrove swamp were studied in Barra de Tecoanapa, Guerrero, Mexico. Original forest included Rhizophora mangle, Laguncularia racemosa, Avicennia germinans and halophytic vegetation, and produced wood (164.03 m3/ha and organic matter (3.9 g/m2/day. A total of 3.5 tons of wood per year were harvested from this area. Later, an average of 2 555 kg of maize per planting cycle were obtained (market value of 88 USD. Succession when the area was abandoned included strictly facultative and glycophyte halophytes (16 families, Cyperaceae and Poaceae were the best represented. After logging, temperatures increased 13 °C in the soil and 11°C in the air, whereas salinity reached 52 psu in the dry season. These modified soil color and sand content increased from 42.6 to 63.4%. Logging was deleterious to species, habitat, biogeochemical and biological cycles, organic matter production, seeds, young plants, genetic exchange conservation of soil and its fertility, coastal protection, and aesthetic value; 3 000 m2 had eroded as the river advanced towards the deforested area (the cost/benefit analysis showed a ratio of 246: 1. There was long-term economic loss for the community and only 30% of the site has recovered after five years.

Comparative Proteomic Analysis of Mature and Immature Oocytes of the Swamp Buffalo (Bubalus bubalis

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Qiang Fu

2016-01-01

Full Text Available Maternal protein components change markedly during mammalian oogenesis. Many of these proteins have yet to be characterized and verified. In this study, a proteomics approach was used to evaluate changes in proteins during oogenesis in the Swamp Buffalo (Bubalus bubalis. Proteins from 500 immature oocytes and 500 in vitro matured oocytes were subjected to two-dimensional electrophoresis, and more than 400 spots were detected. Image analysis indicated that 17 proteins were differentially expressed between the two groups. Eight proteins were identified by mass spectrometry. In mature oocytes, three proteins were down-regulated: major vault protein (MVP, N-acetyllactosaminide β-1,6-N-acetylglucosaminyl-transferase (GCNT-2, and gem-associated protein (GEMIN8, whereas five other proteins, heat shock protein (HSP60, Ras-responsive element-binding protein 1 (RREB-1, heat shock cognate 71 kDa protein (HSC71, hemoglobin subunit α (HBA, and BMP-2-inducible protein kinase (BMP-2K, were up-regulated. The expression profiles of HSP60 and GEMIN8 were further verified by Western blotting. The changes in HSP60 protein expression demonstrate the increasing need for mitochondrial protein importation to facilitate macromolecular assembly during oocyte maturation. The down-regulation of GEMIN8 production implies that RNA splicing is impaired in mature oocytes.

ROUNDTABLE - SESSION 2 EXPLOITATION, CONSERVATION AND LEGISLATION

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EDSMAN L.

2004-01-01

Full Text Available The link between socioeconomics and conservation and the role of legislation in conservation work was discussed in the group with participants from nine European countries. Interest and knowledge among the general public, stakeholders and managers is the key to successful conservation of native crayfish species. Exploitation and conservation do not necessarily exclude each other. A controlled fishery, where it can be sustained, may be an essential tool for conservation by increasing the general awareness and involving more people in the task of protecting the native crayfish species. This strategy is mainly possible for the noble crayfish in the northern part of its distribution, where strong traditions connected to crayfish also exist. A balance between utilisation and overexploitation has to be found and local guidelines for sustainable exploitation produced. Media, the Internet and educational material aimed at schools and stakeholders are excellent ways of reaching a wide audience with information. Universal objectives, rules and regulations at the European level are desirable and the noble crayfish and the stone crayfish should be included in Annex II of the Habitat Directive. Based on this framework detailed regulations are best worked out at the national level, considering the specific crayfish situation in the country. Information about the legislation, the purpose of the legislation and the consequences when not obeying it should be distributed. Stricter regulation of the trade with live alien crayfish is vital because of the associated risk of introducing new diseases and species.

Fitossociologia de dois trechos inundáveis de Matas de Galeria no Distrito Federal, Brasil Phytosociology of two swamped portions of gallery forests in Distrito Federal, Brazil

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Ernestino de Souza Gomes Guarino

2005-09-01

Full Text Available As Matas de Galeria do bioma Cerrado possuem peculiaridades fisionômicas e florísticas que permitem separá-las em dois subtipos: "não-inundável", quando em solos bem drenados; e "inundável", o subtipo menos estudado, em solos mal drenados. O presente trabalho objetivou caracterizar estrutural e floristicamente dois trechos inundáveis das matas dos córregos Acampamento (15°35'S; 48°10'W e Riacho Fundo (15°55'S; 48°02'W no Distrito Federal (DF. Para isso foi alocada em cada Mata uma grade de 160×50 m (0,8 ha, composta por 40 parcelas de 10×20 m (200 m². Todos os indivíduos com diâmetro a 1,30 m da altura do solo (DAP > 3,0 cm foram amostrados, incluindo aqueles mortos ainda em pé. Foram amostrados 6.078 indivíduos, sendo 3.030 no trecho do Acampamento (33 famílias, 49 gêneros e 60 espécies e 3.048 no Riacho Fundo (30 famílias, 41 gêneros, 53 espécies. A área basal e a diversidade (H' calculada para os trechos foram de 47,96 m²/ha e 2,99 nats/ind. (Acampamento, e 41,28 m²/ha e 2,84 nats/ind. (Riacho Fundo, respectivamente. Se comparados com matas anteriormente estudadas no DF os valores de diversidade são baixos, estando na mesma magnitude indicada para as Matas de Brejo (Higrófilas do sudeste brasileiro. Os índices de similaridade indicaram alta semelhança qualitativa (Sørensen 58,0% e quantitativa (Morisita 70,6% entre os trechos estudados, embora uma classificação por TWINSPAN tenha gerado dois grupos distintos, cada qual vinculado a um dos trechos. Os resultados reforçam indicações anteriores de que as Matas de Galeria do DF, ou trechos similares destas, inundáveis ou não, possuem comunidades arbóreas particulares, as quais estão relacionadas à bacia hidrográfica na qual a Mata esta inserida e ao padrão determinante da drenagem do solo.Gallery forests in the Cerrado biome possess physiognomic and floristic peculiarities that allow its division in two subtypes: "non-swamp" located in well drained

Effect of redox conditions on bacterial and fungal biomass and carbon dioxide production in Louisiana coastal swamp forest sediment

International Nuclear Information System (INIS)

Seo, Dong Cheol; DeLaune, Ronald D.

2010-01-01

Fungal and bacterial carbon dioxide (CO 2 ) production/emission was determined under a range of redox conditions in sediment from a Louisiana swamp forest used for wastewater treatment. Sediment was incubated in microcosms at 6 Eh levels (-200, -100, 0, + 100, + 250 and + 400 mV) covering the anaerobic range found in wetland soil and sediment. Carbon dioxide production was determined by the substrate-induced respiration (SIR) inhibition method. Cycloheximide (C 15 H 23 NO 4 ) was used as the fungal inhibitor and streptomycin (C 21 H 39 N 7 O 12 ) as the bacterial inhibitor. Under moderately reducing conditions (Eh > + 250 mV), fungi contributed more than bacteria to the CO 2 production. Under highly reducing conditions (Eh ≤ 0 mV), bacteria contributed more than fungi to the total CO 2 production. The fungi/bacteria (F/B) ratios varied between 0.71-1.16 for microbial biomass C, and 0.54-0.94 for microbial biomass N. Under moderately reducing conditions (Eh ≥ + 100 mV), the F/B ratios for microbial biomass C and N were higher than that for highly reducing conditions (Eh ≤ 0 mV). In moderately reducing conditions (Eh ≥ + 100 mV), the C/N microbial biomass ratio for fungi (C/N: 13.54-14.26) was slightly higher than for bacteria (C/N: 9.61-12.07). Under highly reducing redox conditions (Eh ≤ 0 mV), the C/N microbial biomass ratio for fungi (C/N: 10.79-12.41) was higher than for bacteria (C/N: 8.21-9.14). For bacteria and fungi, the C/N microbial biomass ratios under moderately reducing conditions were higher than that in highly reducing conditions. Fungal CO 2 production from swamp forest could be of greater ecological significance under moderately reducing sediment conditions contributing to the greenhouse effect (GHE) and the global warming potential (GWP). However, increases in coastal submergence associated with global sea level rise and resultant decrease in sediment redox potential from increased flooding would likely shift CO 2 production to bacteria

Physiological and morphological responses to permanent and intermittent waterlogging in seedlings of four evergreen trees of temperate swamp forests.

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Zúñiga-Feest, Alejandra; Bustos-Salazar, Angela; Alves, Fernanda; Martinez, Vanessa; Smith-Ramírez, Cecilia

2017-06-01

Waterlogging decreases a plant's metabolism, stomatal conductance (gs) and photosynthetic rate (A); however, some evergreen species show acclimation to waterlogging. By studying both the physiological and morphological responses to waterlogging, the objective of this study was to assess the acclimation capacity of four swamp forest species that reside in different microhabitats. We proposed that species (Luma apiculata [D.C.] Burret. and Drimys winteri J.R. et G. Forster.) abundant in seasonally and intermittently waterlogged areas (SIWA) would have a higher acclimation capacity than species abundant in the inner swamp (Blepharocalyx cruckshanksii [H et A.] Mied. and Myrceugenia exsucca [D.C.] Berg.) where permanent waterlogging occurs (PWA); it was expected that the species from SIWA would maintain leaf expansion and gas exchange rates during intermittent waterlogging treatments. Conversely, we expected that PWA species would have higher constitutive waterlogging tolerance, and this would be reflected in the formation of lenticels and adventitious roots. Over the course of 2 months, we subjected seedlings to different waterlogging treatments: (i) permanent (sudden, SW), (ii) intermittent (gradual) or (iii) control (field capacity, C). Survival after waterlogging was high (≥80%) for all species and treatments, and only the growth rate of D. winteri subjected to SW was affected. Drimys winteri plants had low, but constant A and g during both waterlogging treatments. Conversely, L. apiculata had the highest A and g values, and g increased significantly during the first several days of waterlogging. In general, seedlings of all species subjected to waterlogging produced more adventitious roots and fully expanded leaves and had higher specific leaf area (SLA) and stomatal density (StD) than seedlings in the C treatment. From the results gathered here, we partially accept our hypothesis as all species showed high tolerance to waterlogging, maintained growth, and had

Acid base status in swamp buffaloes (Bubalus Bubalis fed rice straw and concentrate with addition of sodium

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G Joseph

2001-12-01

Full Text Available An experiment was conducted to study the addition of NaHCO3 and Na2CO3 on acid-base status in swamp buffaloes, Three fistulated buffaloes were each introduced to dietary treatment control diett (50% rice straw + 50% concentrate, control + \\0% NaHCO3 and diet control + 10% Na2CO3 in two times Latin Square Design. The diets contained 9,7% crude protein and 53% TDN to achieve maintenance requirements of the animals. Parameters measured include (l Fed consumption, water consumption and urine volume. (2 pH in rumen fluid, saliva, bLood and urine, (3 natrium mineral content in rumen fluid, saliva, blood and urine. The results of the experiment showed higher pH in the rumen fluid, saliva, blood and urine of buffaloes due to supplementation of NaHCO3 and Na2CO3, Water consumption and urine volume was significanly increased as the effect of Na supplement. The acid-base status of buffaloes was apparently normal in all animals.

A pilot village study to improve Philippine swamp buffalo production using nuclear techniques

International Nuclear Information System (INIS)

Alejandrino, A.L.; Alcantara, J.; Eduardo, S.

1990-01-01

An integrated Philippine village study on carabao (swamp buffalo) production was conducted in a pilot village. The quasi-experimental design was adopted in two areas designated 'with project' (W/P) and 'without project' (W/OP). The farmers' demographic and socio-economic characteristics, livestock management practices and carabao production were monitored during the baseline phase (18 months) and the intervention phase (24 months). The progesterone levels in milk and serum were measured by radioimmunoassay to assess the reproductive status of the carabaos. The improved management scheme for the intervention period consisted of urea + molasses in drinking water, a routine health programme of deworming and vaccination, and breeding by artificial insemination or natural mating. The level of parasitism was low and was mainly caused by infection with Fasciola sp. and amphistomes. Intermediate snail hosts infected with these parasites were found in the study area. Coccidial oocysts and eggs of Mecistocirrus digitatus were occasionally present in the faecal samples. Reproductive traits were improved in both areas during the intervention phase, with the animals in the W/OP area showing a higher increase in pregnancy rate (57.6%) than those in the W/P area (53.7%); however, the increase in the calving rate and calf survival were greater in the W/P area (45.5% and 100%, respectively) than those in the W/OP area (37% and 94.1%, respectively). (author). 10 refs, 3 figs

Nitrogen fate in a subtropical mangrove swamp: Potential association with seawater-groundwater exchange.

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Xiao, Kai; Wu, Jiapeng; Li, Hailong; Hong, Yiguo; Wilson, Alicia M; Jiao, Jiu Jimmy; Shananan, Meghan

2018-04-18

Coastal mangrove swamps play an important role in nutrient cycling at the land-ocean boundary. However, little is known about the role of periodic seawater-groundwater exchange in the nitrogen cycling processes. Seawater-groundwater exchange rates and inorganic nitrogen concentrations were investigated along a shore-perpendicular intertidal transect in Daya Bay, China. The intertidal transect comprises three hydrologic subzones (tidal creek, mangrove and bare mudflat zones), each with different physicochemical characteristics. Salinity and hydraulic head measurements taken along the transect were used to estimate the exchange rates between seawater and groundwater over a spring-neap tidal cycle. Results showed that the maximum seawater-groundwater exchange occurred within the tidal creek zone, which facilitated high-oxygen seawater infiltration and subsequent nitrification. In contrast, the lowest exchange rate found in the mangrove zone caused over-loading of organic matter and longer groundwater residence times. This created an anoxic environment conducive to nitrogen loss through the anammox and denitrification processes. Potential oxidation rates of ammonia and nitrite were measured by the rapid and high-throughput method and rates of denitrification and anammox were measured by the modified membrane inlet mass spectrometry (MIMS) with isotope pairing, respectively. In the whole transect, denitrification accounted for 90% of the total nitrogen loss, and anammox accounted for the remaining 10%. The average nitrogen removal rate was about 2.07g per day per cubic meter of mangrove sediments. Copyright © 2018 Elsevier B.V. All rights reserved.

Substantial improvements not seen in health behaviors following corner store conversions in two Latino food swamps

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Alexander N. Ortega

2016-05-01

Full Text Available Abstract Background The effectiveness of food retail interventions is largely undetermined, yet substantial investments have been made to improve access to healthy foods in food deserts and swamps via grocery and corner store interventions. This study evaluated the effects of corner store conversions in East Los Angeles and Boyle Heights, California on perceived accessibility of healthy foods, perceptions of corner stores, store patronage, food purchasing, and eating behaviors. Methods Household data (n = 1686 were collected at baseline and 12- to 24-months post-intervention among residents surrounding eight stores, three of which implemented a multi-faceted intervention and five of which were comparisons. Bivariate analyses and logistic and linear regressions were employed to assess differences in time, treatment, and the interaction between time and treatment to determine the effectiveness of this intervention. Results Improvements were found in perceived healthy food accessibility and perceptions of corner stores. No changes were found, however, in store patronage, purchasing, or consumption of fruits and vegetables. Conclusions Results suggest limited effectiveness of food retail interventions on improving health behaviors. Future research should focus on other strategies to reduce community-level obesity.

Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons

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Italo Salgado-Leu

2015-11-01

Full Text Available In cultivated aquatic organisms nutritional requirements are critical, not only for their impact on production techniques, but also, for their high incidence on production costs. There is limited knowledge on some species such as the southern Chilean freshwater crayfish, Samastacus spinifrons. In order to generate practical knowledge, a study was carried out to determine protein and carbohydrate content requirements. These factors were evaluated upon their effects on growth and survival of juveniles. For this purpose, individual weight, biomass gain, survival, and feed conversion parameters were measured. The assay was carried out in 42 days, it was conducted in a flow through system, using 21 plastic tanks of 10.6 L capacity. Each tank was seeded with 20 juveniles weighing 50 mg average each. A 3×2 factorial design was proposed with three protein contents (20, 30, 40% and two carbohydrate contents (low: from 16.3 to 23.5% and high: from 34.6 to 35.8%. Six treatments and three replicates were performed. Individuals were fed on apparent satiation once a day. The diets formulated with 30% of protein and the two carbohydrate contents resulted in higher biomass increases, food conversion efficiencies over 26%, and specific growth rate of 0.78%, all displaying significant differences. Survival showed highly significant differences; in all diets were superior to 60%, however the diets with 30% of protein surpassed 90%.

High methane emissions from restored Norway spruce swamps in southern Finland over one growing season

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M. Koskinen

2016-02-01

Full Text Available Forestry-drained peatlands in the boreal region are currently undergoing restoration in order to bring these ecosystems closer to their natural (undrained state. Drainage affects the methane (CH4 dynamics of a peatland, often changing sites from CH4 sources to sinks. Successful restoration of a peatland would include restoration of not only the surface vegetation and hydrology, but also the microbial populations and thus CH4 dynamics. As a pilot study, CH4 emissions were measured on two pristine, two drained and three restored boreal spruce swamps in southern Finland for one growing season. Restoration was successful in the sense that the water table level in the restored sites was significantly higher than in the drained sites, but it was also slightly higher than in the pristine sites. The restored sites were surprisingly large sources of CH4 (mean emissions of 52.84 mg CH4 m-2 d-1, contrasting with both the pristine (1.51 mg CH4 m-2 d-1 and the drained sites (2.09 mg CH4 m-2 d-1. More research is needed to assess whether the high CH4 emissions observed in this study are representative of restored spruce mires in general.

A Late Quaternary palynological and sedimentological record from two coastal swamps at southern Kaitoke, Great Barrier Island, New Zealand

International Nuclear Information System (INIS)

Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

2000-01-01

Pollen and sediment analyses of two cores from southern Kaitoke (Forsythes' Paddock and Blackwells' Bush), Great Barrier Island, show that at c. 7500 cal. yr BP, the area was an estuary with tidal flats and Avicennia. By c. 3000 cal. yr BP, a Restionaceae (Leptocarpus) salt marsh had developed in the estuary as marine influences lessened. By c. cal. 2550 yr BP, fresh water swamp (Cyperacceae-Gleichenia-Leptspermum) had replaced the salt marsh. Conifer-hardwood forest surrounding the southern Kaitoke sites from c. 7500-c. 2800 cal. yr BP was dominated by Daceydium, Metrosideros and Libocedrus. After c. 2800 cal. yr BP Metrosideros was replaced by Agathis, Phyllocladus and Prumnopitys taxifolia, suggesting climatic change to more variable conditions. The presence of the Kaharoa Tephra suggests that major Polynesian deforestation at southern Kaitoke began c. 600 cal. yr BP Minor pre-Kaharoa fire disturbance is evident c. 1750 cal. yr BP and c. 1290-970 cal. yr BP (author). 52 refs., 4 figs., 2 tabs

Carbon Dioxide and Methane Flux Related to Forest Type and Managed and Unmanaged Conditions in the Great Dismal Swamp, USA

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Gutenberg, L. W.; Krauss, K.; Qu, J. J.; Hogan, D. M.; Zhu, Z.; Xu, C.

2017-12-01

The Great Dismal Swamp in Virginia and North Carolina, USA, has been greatly impacted by human use and management for the last few hundred years through logging, ditching, and draining. Today, the once dominant cedar, cypress and pocosin forest types are fragmented due to logging and environmental change. Maple-gum forest has taken over more than half the remaining area of the swamp ecosystem, which is now a National Wildlife Refuge and State Park. The peat soils and biomass store a vast quantity of carbon compared with the size of the refuge, but this store is threatened by fire and drying. This study looks at three of the main forest types in the GDS— maple-sweet gum, tall pine pocosin, and Atlantic white cedar— in terms of their carbon dioxide and methane soil flux. Using static chambers to sample soil gas flux in locally representative sites, we found that cedar sites showed a higher carbon dioxide flux rate as the soil temperature increased than maple sites, and the rate of carbon dioxide flux decreased as soil moisture increased faster in cedar sites than in maple sites. Methane flux increased as temperature increased for pocosin, but decreased with temperature for cedar and maple. All of the methane fluxes increased as soil moisture increased. Cedar average carbon dioxide flux was statistically significantly different from both maple and pocosin. These results show that soil carbon gas flux depends on soil moisture and temperature, which are factors that are changing due to human actions, as well as on forest type, which is also the result of human activity. Some of these variables may be adjustable by the managers of the land. Variables other than forest type, temperature and soil moisture/inundation may also play a role in influencing soil flux, such as stand age, tree height, composition of the peat and nutrient availability, and source of moisture as some sites are more influenced by groundwater from ditches and some more by rainfall depending on the

INTRODUCTION : THE EU-NETWORK CRAYNET- IMPACTS ON FUNDAMENTAL QUESTIONS

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SOUTY-GROSSET C.

2005-07-01

Full Text Available The European network CRAYNET “European crayfish as keystone species-linking science, management and economics with sustainable environmental quality” emphasises knowledge-based management strategies. The CRAYNET meetings concentrate on certain topics: monitoring in conservation and management of natives; interaction between natives and aliens; control of aliens; habitat restoration; reintroduction and restocking; legislation; education. The Irish meeting (Kilkenny, 2003 “The endangered native crayfish Austropotamobius pallipes: bioindicator and heritage species” initiated debates about (1 what is a bioindicator, a flagship species or a heritage species?; (2 the problem of species complexes and the need to clarify and resolve taxonomy before management; and (3 what is meant by biodiversity in the context of European crayfish? The Norwegian meeting (Halden, 2003 “European native, crayfish with a special focus on Astacus astacus: linking socioeconomics and conservation ” involved roundtables about (1 threats to indigenous population of crayfish at a landscape level; (2 exploitation, conservation, legislation; (3 reintroduction of indigenous crayfish, habitat restoration and monitoring; and (4 the urgent need for joint research about pathology. The present meeting (Innsbruck, 2004 “European native crayfish in relation to land-use and habitat deterioration with a special focus on Austropotamobius torrentim” aims to identify the species protection programs, to examine if legislation is working well in protecting vulnerable species, the state of advances about conservation genetics and how to make progress in education of the public. A permanent connection between the 12 core members provides opportunities to check the needed lines of research, to prepare recommendations, and to gather information for an atlas on the distribution of crayfish species in Europe as well as to prepare leaflets for the public.

Feasibility, density and growth of culture of freshwater crayfish (Decapoda: Cherax Quadricarinatus in Sinaloa, México

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Juan Francisco Arzola González

2012-09-01

Full Text Available Feasibility, density and growth of culture of freshwater crayfish (Cherax quadricarinatus in Sinaloa were analyzed between September, 2005 and January, 2006. The densities were 7 (reservoir 1 and 16 (reservoir 2 org/m-2. Applied a method not parametrico (Kruskal-Wallis, the variables of response were density, weight and sex, the experimental unit the reservoirs. Samplings were weekly and 40 lobsters were captured in tubes of PVC. Total and cefalotorácica length ((LT y LC in mm and total weight (PT in g of the organisms were recorded, the biometric correlations were realized and von Bertalanffy estimated the growth for the model of von Bertallanfy. The major average was obtained in 41.2 g to a density of 7 org/m, though her k (growth rate coincided with the reservoirs with 0.30, in addition, the lobsters they presented a growth of isometric type. From the first year, usefulness of $3,419,165.00 obtained, that represented 26.8 % of the total of income, keeping a growth like that supported until the fifth year (2011. The financial evaluation determined that the investment is profitable economically, his analysis of VAN was $9,060,554.00, and in agreement to the financial indicators, this value was ideal for the accomplishment of the project. As indicator of the profitability, the TIR resulted in 66 %, being major that the minimal acceptable rate of performance and concluding the profitability of the culture in 59 %. Likewise, Sinaloa's condition, for his geographical location and the results ofthe growth, the heights, the performance of the lobster and of the financial analysis of the culture, indicated to C. quadricarinatusas an alternative of development in the region, being the lobster of interest in acuiculture of new species in tropical areas, thoughin Sinaloa the investigations are practically void with ends of commercial production.

High blood oxygen affinity in the air-breathing swamp eel Monopterus albus.

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Damsgaard, Christian; Findorf, Inge; Helbo, Signe; Kocagoz, Yigit; Buchanan, Rasmus; Huong, Do Thi Thanh; Weber, Roy E; Fago, Angela; Bayley, Mark; Wang, Tobias

2014-12-01

The Asian swamp eel (Monopterus albus, Zuiew 1793) is a facultative air-breathing fish with reduced gills. Previous studies have shown that gas exchange seems to occur across the epithelium of the buccopharyngeal cavity, the esophagus and the integument, resulting in substantial diffusion limitations that must be compensated by adaptations in others steps of the O₂ transport system to secure adequate O₂ delivery to the respiring tissues. We therefore investigated O₂ binding properties of whole blood, stripped hemoglobin (Hb), two major isoHb components and the myoglobin (Mb) from M. albus. Whole blood was sampled using indwelling catheters for blood gas analysis and determination of O₂ equilibrium curves. Hb was purified to assess the effects of endogenous allosteric effectors, and Mb was isolated from heart and skeletal muscle to determine its O₂ binding properties. The blood of M. albus has a high O₂ carrying capacity [hematocrit (Hct) of 42.4±4.5%] and binds O₂ with an unusually high affinity (P₅₀=2.8±0.4mmHg at 27°C and pH7.7), correlating with insensitivity of the Hb to the anionic allosteric effectors that normally decrease Hb-O₂ affinity. In addition, Mb is present at high concentrations in both heart and muscle (5.16±0.99 and 1.08±0.19mg ∙ g wet tissue⁻¹, respectively). We suggest that the high Hct and high blood O₂ affinity serve to overcome the low diffusion capacity in the relatively inefficient respiratory surfaces, while high Hct and Mb concentration aid in increasing the O₂ flux from the blood to the muscles. Copyright © 2014 Elsevier Inc. All rights reserved.

How could a freshwater swamp produce a chemical signature characteristic of a saltmarsh?

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McCloskey, Terrence; Smith, Christopher G.; Liu, Kam-biu; Marot, Marci E.; Haller, Christian

2018-01-01

Reduction–oxidation (redox) reaction conditions, which are of great importance for the soil chemistry of coastal marshes, can be temporally dynamic. We present a transect of cores from northwest Florida wherein radical postdepositional changes in the redox regime has created atypical geochemical profiles at the bottom of the sedimentary column. The stratigraphy is consistent along the transect, consisting of, from the bottom upward, carbonate bedrock, a gray clay, an organic mud section, a dense clay layer, and an upper organic mud unit representing the current saltwater marsh. However, the geochemical signature of the lower organic mud unit suggests pervasive redox reactions, although the interval has been identified as representing a freshwater marsh, an unlikely environment for such conditions. Analyses indicate that this discrepancy results from postdepositional diagenesis driven by millennial-scale environmental parameters. Rising sea level that led to the deposition of the capping clay layer, created anaerobic conditions in the freshwater swamp interval, and isolated it hydrologically from the rest of the sediment column. The subsequent infiltration of marine water into this organic material led to sulfate reduction, the buildup of H2S and FeS, and anoxic conditions. Continued sulfidation eventually resulted in euxinic conditions, as evidenced by elevated levels of Fe, S, and especially Mo, the diagnostic marker of euxinia. Because this chemical transformation occurred long after the original deposition the geochemical signature does not reflect soil chemistry at the time of deposition and cannot be used to infer syn-depositional environmental conditions, emphasizing the importance of recognizing diagenetic processes in paleoenvironmental studies.

Mercury bioaccumulation along food webs in temperate aquatic ecosystems colonized by aquatic macrophytes in south western France.

Science.gov (United States)

Gentès, Sophie; Maury-Brachet, Régine; Guyoneaud, Rémy; Monperrus, Mathilde; André, Jean-Marc; Davail, Stéphane; Legeay, Alexia

2013-05-01

Mercury (Hg) is considered as an important pollutant for aquatic systems as its organic form, methylmercury (MeHg), is easily bioaccumulated and bioamplified along food webs. In various ecosystems, aquatic periphyton associated with macrophyte was identified as an important place for Hg storage and methylation by microorganisms. Our study concerns temperate aquatic ecosystems (South Western France) colonized by invasive macrophytes and characterized by high mercury methylation potentials. This work establishes original data concerning Hg bioaccumulation in organisms (plants, crustaceans, molluscs and fish) from five contrasting ecosystems. For low trophic level species, total Hg (THg) concentrations were low (from 27±2ngTHgg(-1)dw in asiatic clam Corbicula fluminea to 418±114ngTHgg(-1)dw in crayfish Procambarus clarkii). THg concentrations in some carnivorous fish (high trophic level) were close to or exceeded the International Marketing Level (IML) with values ranging from 1049±220ngTHgg(-1)dw in pike perch muscle (Sander lucioperca) to 3910±1307ngTHgg(-1)dw in eel muscle (Anguilla Anguilla). Trophic levels for the individuals were also evaluated through stable isotope analysis, and linked to Hg concentrations of organisms. A significant Hg biomagnification (r(2)= 0.9) was observed in the Aureilhan lake, despite the absence of top predator fish. For this site, Ludwigia sp. periphyton, as an entry point of Hg into food webs, is a serious hypothesis which remains to be confirmed. This study provides a first investigation of Hg transfer in the ecosystems of south western France and allows the assessment of the risk associated with the presence of Hg in aquatic food webs. Copyright © 2013 Elsevier Inc. All rights reserved.

Studies of axon-glial cell interactions and periaxonal K+ homeostasis--II. The effect of axonal stimulation, cholinergic agents and transport inhibitors on the resistance in series with the axon membrane.

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Hassan, S; Lieberman, E M

1988-06-01

The small electrical resistance in series with the axon membrane is generally modeled as the intercellular pathway for current flow through the periaxonal glial (Schwann cell) sheath. The series resistance of the medial giant axon of the crayfish, Procambarus clarkii, was found to vary with conditions known to affect the electrical properties of the periaxonal glia. Series resistance was estimated from computer analysed voltage waveforms generated by axial wire-constant current and space clamp techniques. The average series resistance for all axons was 6.2 +/- 0.5 omega cm2 (n = 128). Values ranged between 1 and 30 omega cm2. The series resistance of axons with low resting membrane resistance (less than 1500 omega cm2) increased an average of 30% when stimulated for 45 s to 7 min (50 Hz) whereas the series resistance of high membrane resistance (greater than 1500 omega cm2) axons decreased an average of 10%. Carbachol (10(-7) M) caused the series resistance of low membrane resistance axons to decrease during stimulation but had no effect on high membrane resistance axons. d-Tubocurare (10(-8) M) caused the series resistance of high membrane resistance axons to increase during stimulation but had no effect on low membrane resistance axons. Bumetanide, a Na-K-Cl cotransport inhibitor and low [K+]o, prevented the stimulation-induced increase in series resistance of low membrane resistance axons but had no effect on the high membrane resistance axons. The results suggest that the series resistance of axons varies in response to the activity of the glial K+ uptake mechanisms stimulated by the appearance of K+ in the periaxonal space during action potential generation.(ABSTRACT TRUNCATED AT 250 WORDS)

Prediction of the neuropeptidomes of members of the Astacidea (Crustacea, Decapoda) using publicly accessible transcriptome shotgun assembly (TSA) sequence data.

Science.gov (United States)

Christie, Andrew E; Chi, Megan

2015-12-01

The decapod infraorder Astacidea is comprised of clawed lobsters and freshwater crayfish. Due to their economic importance and their use as models for investigating neurochemical signaling, much work has focused on elucidating their neurochemistry, particularly their peptidergic systems. Interestingly, no astacidean has been the subject of large-scale peptidomic analysis via in silico transcriptome mining, this despite growing transcriptomic resources for members of this taxon. Here, the publicly accessible astacidean transcriptome shotgun assembly data were mined for putative peptide-encoding transcripts; these sequences were used to predict the structures of mature neuropeptides. One hundred seventy-six distinct peptides were predicted for Procambarus clarkii, including isoforms of adipokinetic hormone-corazonin-like peptide (ACP), allatostatin A (AST-A), allatostatin B, allatostatin C (AST-C) bursicon α, bursicon β, CCHamide, crustacean hyperglycemic hormone (CHH)/ion transport peptide (ITP), diuretic hormone 31 (DH31), eclosion hormone (EH), FMRFamide-like peptide, GSEFLamide, intocin, leucokinin, neuroparsin, neuropeptide F, pigment dispersing hormone, pyrokinin, RYamide, short neuropeptide F (sNPF), SIFamide, sulfakinin and tachykinin-related peptide (TRP). Forty-six distinct peptides, including isoforms of AST-A, AST-C, bursicon α, CCHamide, CHH/ITP, DH31, EH, intocin, myosuppressin, neuroparsin, red pigment concentrating hormone, sNPF and TRP, were predicted for Pontastacus leptodactylus, with a bursicon β and a neuroparsin predicted for Cherax quadricarinatus. The identification of ACP is the first from a decapod, while the predictions of CCHamide, EH, GSEFLamide, intocin, neuroparsin and RYamide are firsts for the Astacidea. Collectively, these data greatly expand the catalog of known astacidean neuropeptides and provide a foundation for functional studies of peptidergic signaling in members of this decapod infraorder. Copyright © 2015 Elsevier Inc

Radionuclides distribution in artificial reservoir V-17 (old swamp)

Energy Technology Data Exchange (ETDEWEB)

Kuzmenkova, N. [Vernadsky Institute of geochemistry and analytical chemistry RAS (Russian Federation); Vlasova, I.; Sapozhnikov, Y.; Kalmykov, S. [Lomonosov MSU, Chemistry Dep. (Russian Federation); Pryakhin, E. [Urals Research center for radiation medicine (Russian Federation); Ivanov, I. [FSUE Mayak PA (Russian Federation)

2014-07-01

Reservoir V-17 (Old Swamp) was formed as a result of the construction of dams in 1952 and 1954 (MAYAK Production Association),located in a natural depression relief. Intermediate level liquid radioactive wastes (ILLW) have been discharged to this reservoir since 1949. The water surface area of the lake is 0.13 km{sup 2} with the volume of 0.36 Mm{sup 3}. The maximum depth is 6.5 m with the average value of 2.8 m. Among 74 PBq deposited to the reservoir, the major portion is concentrated in the bottom sediments (as determined in 2007). The aim of this study is to determine radionuclide distribution among abiotic and biotic aquatic components, that includes study of various radionuclides distribution between water and bottom sediments, their speciation and evaluation of condition of zooplankton community. As a result of field research at the reservoir, 4 sampling locations were chosen from which bottom sediments, water samples and some hydrobionts were collected. Pore waters were separated from the wet sediments by high-speed centrifugation. All samples were analyzed by gamma spectrometry using HPGe detector Canberra GR 3818.The radioactivity of tritium in the pore and lake waters was determined by liquid-scintillation spectrometry. The strontium-90 was detected by Cherenkov counting of the daughter {sup 90}Y. The preliminary data show for sediments samples: for {sup 137}Cs amount varies from 75,5 KBq/g to 232 KBq/g, {sup 154}Eu - from 460 to 990 Bq/g, {sup 241}Am - from 1 to 4 KBq/g, {sup 134}Cs - from 50 to 220 Bq/g; for water samples: large contribution from strontium-90 and tritium (varies from 2 to 25 Bq/g). Pore water contains medium amount of radionuclides between sediments and water samples. For {sup 137}Cs varies between 160 to 1100 Bq/g, {sup 154}Eu - from 0,1 to 0,3 Bq/g, {sup 241}Am - from 0,3 to 11 Bq/g, {sup 134}Cs - from 0,1 to 1,7 Bq/g. Variation depends on the sampling place. Activity distribution among hydrobionts was studied by digital Radiography

Heat death in the crayfish Austropotamobius pallipes: thermal inactivation of muscle membrane-bound ATPases in warm and cold adapted animals

Energy Technology Data Exchange (ETDEWEB)

Gladwell, R T

1976-01-01

The thermal sensitivity of the membrane-bound Mg/sup 2 +/ and Na/sup +/ + K/sup +/ + Mg/sup 2 +/ ATPases from the abdominal flexor muscles of 10 and 25/sup 0/C acclimated animals was investigated. The Mg/sup 2 +/ ATPase was inactivated by milder heat treatments than the Na/sup +/ + K/sup +/ + Mg/sup 2 +/ ATPase. The effect of high lethal temperatures on the Mg/sup 2 +/ ATPase was dependent on the previous thermal history of the animal, the enzyme preparations from 10/sup 0/C acclimated animals being more sensitive than those from 25/sup 0/C acclimated animals. The thermal sensitivity of the Na/sup +/ + K/sup +/ + Mg/sup 2 +/ ATPase was not altered by temperature acclimation. The change in the thermal sensitivity of the Mg/sup 2 +/ ATPase with the acclimation temperature of the whole animal was correlated with the survival times of 10 and 25/sup 0/C acclimated animals. The K/sub m/ and V/sub max/ of the ATPases was investigated and the K/sub m/ of both enzymes was found to decrease with acclimation of the whole animal to lower temperatures, so that enzyme/substrate affinity increased with cold acclimation. It was concluded that the inactivation of the muscle Mg/sup 2 +/ ATPase was the primary lesion of heat death in the crayfish, and that the changes in the kinetic properties of the ATPases were an important mechanism in the process of physiological temperature acclimation.

Behavioral and electrophysiological evidence for the mechanisms involved in the detection of ionizing radiations by the crayfish Pacifastacus trowbridgii

International Nuclear Information System (INIS)

Rodriguez, A.

1976-01-01

The light-adapted crayfish, Pacifastacus trowbridgii, displayed a behavioral response to exposure to 300 kV x-rays at exposure rates of 10 to 30 R/s. Within this range, the proportion of subjects that responded increased with an increase in exposure rate. The response latency was inversely proportional to the exposure rate. Ophthalmectomized animals exhibited a similar response with a significantly shorter latency than the intact animals at the same exposure rate (30 R/s). Partial body exposure of ophthalmectomized animals also elicited a behavioral response and indicated that a radiation-sensitive receptor was located in the abdomen. X-ray exposure of the dark-adapted compound eye evoked an electroretinogram (ERG) that was similar to the light evoked ERG. The x-ray evoked ERG amplitude was found to be dependent on total exposure for stimulus durations of 300 ms or less. With stimulus durations greater than 300 ms, the ERG amplitude increased in relation to the logarithm of the exposure rate. Similar responses with light indicated that the mechanism of interaction may be the same for x-rays. The time course for maximal dark-adaptation, after a 500 ms exposure to 3.85 ft-c of light, was comparable for both x-ray and light exposure (9 min). Differences observed in ERG amplitude between the light and x-ray evoked responses during the initial recovery period can be attributed to absorption of light by migrating accessory pigments or by differential interaction of light with photosensitive pigments in the eye

RECENT SUSPECT CASES AND A PILOT DETECTION STUDY

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KOZUBÍKOVÁ E.

2006-01-01

Full Text Available There are only very limited reports about the occurrence of the crayfish plague in Czechia. In recent years, mass mortalities of Astacus spp. with symptoms of possible crayfish plague were noticed in three streams in the country – two in Central Bohemia (1998-9 and one in Silesia (2004. Three dead individuals from the last outbreak were examined for the presence of the crayfish plague pathogen, Aphanomyces astaci, by observation of the presence of hyphae in their cuticle and by a PCR-based diagnostic method. In all three cases the detection was positive. Although causes of mass mortalities from two other localities lack such a direct confirmation, the indirect evidence supports the same conclusion. The main potential vector of A. astaci in Czechia is the American spiny-cheeck crayfish Orconectes limosus, widespread in large rivers of the western part of the country and in various isolated standing waters. Using the same molecular method, we investigated the presence of A. astaci in living O. limosus individuals from six localities (three running and three standing waters. The analysis indicated the presence of the pathogen in animals from five out of six investigated Orconectes populations. One of them is present in the stream where two European Astacus species had gone extinct in 1998-9. Our results suggest that the crayfish plague is still present in Czechia, and that populations of O. limosus represent a reservoir for the crayfish plague pathogen, which directly endangers populations of the native crayfish.

The Effect of Seed Soaking with Rhizobacteria Pseudomonas alcaligenes on the Growth of Swamp Cabbage (Ipomoea reptans Poir)

Science.gov (United States)

Widnyana, I. K.; Ngga, M.; Sapanca, P. L. Y.

2018-01-01

The research was conducted to determine the effect of seed soaking with suspense of P. alcaligenes isolate KtSl, TrN2, and TmAl to the growth of swamp cabbage. The research has been initially developed on tomatoes. In this research, Randomized Block Design was chosen as its model while the data analysis was performed by using SPSS v.17 for Windows. Three types of treatment were administered towards P. alcaligenes, namely isolating, soaking, and growing the medium. Some observed parameters were germination and growth. The results showed that seed soaking treatments with suspense P. alcaligenes fostered the germination 25% faster, enhanced the crop up to 24.4%, increased the number of leaves up until 23.15%, lengthen stems to 25%, lengthen the roots up to 46.90%, and increase the fresh weight of stems up until 67.07% and oven-dry weight of stem up to 84.21% compared to the control treatment. The best response of treatment for germination speed was soaking seeds with P. alcaligenes TrN2 for 20 minutes on both NB (Natrium Broth) and PDB (Potato Dextrose Broth) media.

Socioeconomic Determinants of Income From Fresh and Processed ...

African Journals Online (AJOL)

A total sample size of 84 crayfish marketers were in all randomly selected across three major Cray ... determine the income derived from fresh crayfish marketing while household size and purchasing ... EMAIL FULL TEXT EMAIL FULL TEXT

Effects of waste drilling fluid on bacterial isolates from a mangrove swamp oilfield location in the Niger delta of Nigeria

Energy Technology Data Exchange (ETDEWEB)

Benka-Coker, M.O.; Olumagin, A. [Benin Univ. (Nigeria). Dept. of Microbiology

1996-03-01

Four bacteria strains isolated from a mangrove swamp oilfield location in the Niger Delta of Nigeria were cultured aerobically in the presence of 1.0% waste drilling fluid, to determine the effect of the waste on their growth. A 2-h lag phase of growth was produced by the waste in cultures of Micrococcus and Pseudomonas species, while the waste increased the lag phases of Alcaligenes and Staphylococcus species to 4 h. The exponential phase of growth of Pseudomonas sp. was depressed by the waste drilling fluid but fluid stimulated the exponential phases of Micrococcus and Alcaligenes spp. There was enhancement of the growth rate of Alcaligenes and Micrococcus spp. while those of Staphylococcus and Pseudonomas spp. were decreased. The depressed growth rates of Staphylococcus and Pseudonomas spp. in the presence of the waste drilling fluid might lead to a decrease in their contribution to the removal of the waste from the environment during spillage or disposal and, therefore, may result in an accumulation of the waste in the environment. (author)

Effects of waste drilling fluid on bacterial isolates from a mangrove swamp oilfield location in the Niger delta of Nigeria

International Nuclear Information System (INIS)

Benka-Coker, M.O.; Olumagin, A.

1996-01-01

Four bacteria strains isolated from a mangrove swamp oilfield location in the Niger Delta of Nigeria were cultured aerobically in the presence of 1.0% waste drilling fluid, to determine the effect of the waste on their growth. A 2-h lag phase of growth was produced by the waste in cultures of Micrococcus and Pseudomonas species, while the waste increased the lag phases of Alcaligenes and Staphylococcus species to 4 h. The exponential phase of growth of Pseudomonas sp. was depressed by the waste drilling fluid but fluid stimulated the exponential phases of Micrococcus and Alcaligenes spp. There was enhancement of the growth rate of Alcaligenes and Micrococcus spp. while those of Staphylococcus and Pseudonomas spp. were decreased. The depressed growth rates of Staphylococcus and Pseudonomas spp. in the presence of the waste drilling fluid might lead to a decrease in their contribution to the removal of the waste from the environment during spillage or disposal and, therefore, may result in an accumulation of the waste in the environment. (author)

Adaptation of Cambarus bartonii cavatus (Hay) (Decapoda: Cambaridae) to acid mine-polluted waters

Energy Technology Data Exchange (ETDEWEB)

Gallaway, M.S.; Hummon, W.D. (Ohio University, Athens, OH (USA). Dept. of Zoological and Biomedical Sciences)

1991-09-01

Juvenile crayfish {ital Cambarus bartonii cavatus} were taken from two nearby sites on Big Four Creek, Vinton County, OH. Water from upstream (UpS) and downstream (DnS) sites had total conductivities of 250 {mu}S and 600 {mu}S ({mu}S {mu}mho/cm{sup 2}) at 25{degree}C. Non-carbonate conductivity was largely made up of sulfuric acid and heavy metals. Carbonates represented 40% of the conductivity at UpS but were absent from DnS. With only 100 {mu}S of carbonate buffering capacity, water from UpS had little ability to neutralize acidic input, and this was easily overcome. Tests in seven solutions ranging between 250 {mu}S and 5000 {mu}S showed that: (1) mortality of crayfish was affected by the conductivity of test solutions, (2) DnS crayfish survived longer than UpS crayfish in all test conditions except the clean UpS water, and (3) there was no interaction term between source area and strength of conductivity on longevity. Attempts to acclimate crayfishes to higher levels of mine acid over short time periods were unsuccessful. Crayfish mortality under low acid conditions was not increased by addition of iron precipitate, though deaths were associated with ecdysis at intermediate and higher concentrations of mine acid. If DnS, but not UpS, crayfishes of this subspecies have acclimatized to intermediate concentrations of mine acid, then we infer a regime of semi-isolated reproduction over a short distance of streambed. Such an adaptation might have evolved following long-term exposure to low level, naturally-occurring acid seepage from coal outcrops, with success depending on the pre-adaptation of this subspecies to life in waters that are naturally low in carbonate buffering capacity. 37 refs., 3 tabs.

A case study on fuel oil contamination in a mangrove swamp in Hong Kong

Energy Technology Data Exchange (ETDEWEB)

Tam, N.F.Y.; Wong, T.W.Y.; Wong, Y.S. [City University of Hong Kong, Kowloon (Hong Kong). Department of Biology

2005-07-01

Mangroves commonly found along tropical and subtropical coastlines are susceptible to oil pollution. In December 2000, around 500 1 m tall Kandelia candel saplings at the age of 3-5 years old located at the foreshore region of Sheung Pak Nai swamp, Hong Kong SAR, were found to be damaged by oil pollution. More than 80% of the saplings were either dead or washed away and leaving less than 5% healthy saplings with dense green leaves. Elevated concentrations of light n-alkanes (ranging from n-C{sub 14} to n-C{sub 20}), pristane and phytane were recorded in surface sediments collected in December 2000. The ratio between light and total n-alkanes was 0.4. The total petroleum hydrocarbons (60-80 {mu}g g{sup -1} TPH) and unresolved complex mixtures (60-70 {mu}g g{sup -1} UCM) were higher than the background values of other mangrove sediments in Hong Kong, which were 40 and 20 {mu}g g{sup -1}, respectively. In certain root zone sediments, TPH concentrations were above 1000 {mu}g g{sup -1}. These results suggest that surface sediments in Sheung Pak Nai were contaminated by petroleum oil, most likely by illegal discharge of fuel oil which occurred between 1998 and 2002. One year later, in December 2001, unhealthy saplings had recovered and re-grown. The concentrations of TPH and UCM in sediments declined to around 40 {mu}g g{sup -1}, pristane and phytane dropped by 80%, and the ratio of light to total n-alkanes was 0.15, suggesting that residual oil in sediments was weathered leading to a remarkable recovery of the unhealthy saplings. (author)

Benefits of the fire mitigation ecosystem service in the Great Dismal Swamp National Wildlife Refuge, Virginia, USA

Science.gov (United States)

Parthum, Bryan M.; Pindilli, Emily J.; Hogan, Dianna

2017-01-01

 The Great Dismal Swamp (GDS) National Wildlife Refuge delivers multiple ecosystem services, including air quality and human health via fire mitigation. Our analysis estimates benefits of this service through its potential to reduce catastrophic wildfire related impacts on the health of nearby human populations. We used a combination of high-frequency satellite data, ground sensors, and air quality indices to determine periods of public exposure to dense emissions from a wildfire within the GDS. We examined emergency department (ED) visitation in seven Virginia counties during these periods, applied measures of cumulative Relative Risk to derive the effects of wildfire smoke exposure on ED visitation rates, and estimated economic losses using regional Cost of Illness values established within the US Environmental Protection Agency BenMAP framework. Our results estimated the value of one avoided catastrophic wildfire in the refuge to be \\$3.69 million (2015 USD), or \\$306 per hectare of burn. Reducing the frequency or severity of extensive, deep burning peatland wildfire events has additional benefits not included in this estimate, including avoided costs related to fire suppression during a burn, carbon dioxide emissions, impacts to wildlife, and negative outcomes associated with recreation and regional tourism. We suggest the societal value of the public health benefits alone provides a significant incentive for refuge mangers to implement strategies that will reduce the severity of catastrophic wildfires.

Sedimentology and ichnology of Neogene Coastal Swamp deposits in the Niger Delta Basin, Nigeria

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Ezeh Sunny C.

2016-09-01

Full Text Available Often analyses of depositional environments from sparse data result in poor interpretation, especially in multipartite depositional settings such as the Niger Delta. For instance, differentiating channel sandstones, heteroliths and mudstones within proximal environments from those of distal facies is difficult if interpretations rely solely on well log signatures. Therefore, in order to achieve an effective and efficient interpretation of the depositional conditions of a given unit, integrated tools must be applied such as matching core descriptions with wireline log signature. In the present paper cores of three wells from the Coastal Swamp depositional belt of the Niger Delta are examined in order to achieve full understanding of the depositional environments. The well sections comprise cross-bedded sandstones, heteroliths (coastal and lower shoreface and mudstones that were laid down in wave, river and tidal processes. Interpretations were made from each data set comprising gamma ray logs, described sedimentological cores showing sedimentary features and ichnological characteristics; these were integrated to define the depositional settings. Some portions from one of the well sections reveal a blocky gamma ray well log signature instead of a coarsening-upward trend that characterises a shoreface setting while in other wells the signatures for heteroliths at some sections are bell blocky in shaped rather than serrated. Besides, heteroliths and mudstones within the proximal facies and those of distal facies were difficult to distinguish solely on well log signatures. However, interpretation based on sedimentology and ichnology of cores from these facies was used to correct these inconsistencies. It follows that depositional environment interpretation (especially in multifarious depositional environments such as the Niger Delta should ideally be made together with other raw data for accuracy and those based solely on well log signatures should

Reflorestamento de manguezais e o valor de resgate para o seqüestro de carbono atmosférico The reforestation of mangrove swamps and its value in atmospheric carbon sequestration

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Sérgio de Mattos Fonseca

2003-12-01

Full Text Available Os autores afirmam a relevância do reflorestamento de manguezais para projetos de seqüestro de carbono atmosférico, dentro dos princípios do chamado mecanismo de desenvolvimento limpo (MDL,definidos em diversas arenas técnicas e políticas internacionais, dentro da Convenção de Mudanças Climáticas. Descrevem um projeto de pesquisa em andamento, que inclui estudo de caso focalizado em manguezais da laguna de Itaipu (Niterói, RJ, cujo objetivo é selecionar e fazer medições preliminares de parâmetros ecológicos e socioambientais relevantes para a valoração econômica e financeira dos benefícios do reflorestamento. A seleção e as medições servirão como estudo de viabilidade para que projetos semelhantes se qualifiquem para obter apoio financeiro e alcançar sucesso técnico, gerando benefícios ambientais e sociais.The article argues that the reforestation of mangrove swamps is of relevance to projects for sequestering atmospheric carbon, within the principles of the Clean Development Mechanism (CDM currently being defined in different technical and political arenas as part of the Convention on Climate Change. The text describes a research project currently under way that includes a case study of mangrove swamps in the Itaipu Lagoon in Niterói, RJ. The project's goal is to select and take preliminary measurements of the ecological and socio-environmental parameters pertinent to the economic and financial valuation of the benefits of reforestation. These parameters will serve as part of feasibility studies that determine whether similar projects up for financing by the CDM qualify for financial support and whether they will achieve technical success that brings environmental and social benefits to the various social actors involved.

76 FR 3126 - Final Determination of the Assistant Administrator for Water Pursuant to Section 404(c) of the...

Science.gov (United States)

2011-01-19

... macroinvertebrates, up to 46 species of amphibians and reptiles, 4 species of crayfish, and 5 species of fish, as... amphibians, reptiles, crayfish, and bird species that depend on downstream waters for food or habitat... be, in turn, substantial effects on fish, amphibian, and bird populations that rely on these...

Gonad development and size at maturity of the male mud crab Scylla paramamosain (Forsskål, 1755 in a tropical mangrove swamp

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Md. Sherazul Islam

2013-12-01

Full Text Available The reproductive traits and size at sexual maturity of the male mud crab Scylla paramamosain were investigated in Pak Phanang mangrove swamps, Thailand. Samples were taken seven times from the local middlemen mud crab traders during June 2006 to January 2008. Gonad development was determined based on histological appearance that was classified into three stages: 1 Immature (Spermatogonia, 2 Maturing (Spermatocytes and 3 Mature (Spermatids and Spermatozoa. Among the sample population, the highest 72% was under gonad development stage I, whereas mature stage III was only 12%. The size at first maturity was estimated by the external allometric growth and histological observation of gonad. The size at which 50% of individuals attain sexual maturity was estimated by the two mathematical models such as probit analysis and logistic curve. The mean size at first sexual maturity and 50% maturation of male S. paramamosain were 96 mm and 109 mm internal carapace width (ICW which revealed that 88% individuals were immature. The present result suggested that the minimum legal size of male S. paramamosain capture should be >110 mm ICW.

Are rapid transitions between invasive and native species caused by alternative stable states, and does it matter?

Science.gov (United States)

Hansen, Gretchen J A; Ives, Anthony R; Vander Zanden, M Jake; Carpenter, Stephen R

2013-10-01

Rapid transitions in ecosystem structure, or regime shifts, are a hallmark of alternative stable states (ASS). However, regime shifts can occur even when feedbacks are not strong enough to cause ASS. We investigated the potential for ASS to explain transitions between dominance of an invasive species, rusty crayfish (Orconectes rusticus), and native sunfishes (Lepomis spp.) in northern Wisconsin (USA) lakes. A rapid transition from Lepomis to rusty crayfish dominance occurred as rusty crayfish invaded Trout Lake, and the reverse transition resulted from an eight-year experimental removal of rusty crayfish from Sparkling Lake. We fit a stage-structured population model of species interactions to 31 years of time-series data from each lake. The model identified water level as an important driver, with drought conditions reducing rusty crayfish recruitment and allowing Lepomis dominance. The maximum-likelihood parameter estimates of the negative interaction between rusty crayfish and Lepomis led to ASS in the model, where each species was capable of excluding the other within a narrow range of environmental conditions. However, uncertainty in parameter estimates made it impossible to exclude the potential that rapid transitions were caused by a simpler threshold response lacking alternative equilibria. Simulated forward and backward transitions between species dominance occurred at different environmental conditions (i.e., hysteresis), even when the parameters used for simulation did not predict ASS as a result of slow species responses to environmental drivers. Thus, ASS are possible, but by no means certain, explanations for rapid transitions in this system, and our results highlight the difficulties associated with distinguishing ASS from other types of threshold responses. However, whether regime shifts are caused by ASS may be relatively unimportant in this system, as the range of conditions over which transitions occur is narrow, and under most conditions, the

Bringing Healthy Retail to Urban "Food Swamps": a Case Study of CBPR-Informed Policy and Neighborhood Change in San Francisco.

Science.gov (United States)

Minkler, Meredith; Estrada, Jessica; Thayer, Ryan; Juachon, Lisa; Wakimoto, Patricia; Falbe, Jennifer

2018-04-09

In urban "food swamps" like San Francisco's Tenderloin, the absence of full-service grocery stores and plethora of corner stores saturated with tobacco, alcohol, and processed food contribute to high rates of chronic disease. We explore the genesis of the Tenderloin Healthy Corner Store Coalition, its relationship with health department and academic partners, and its contributions to the passage and implementation of a healthy retail ordinance through community-based participatory research (CBPR), capacity building, and advocacy. The healthy retail ordinance incentivizes small stores to increase space for healthy foods and decrease tobacco and alcohol availability. Through Yin's multi-method case study analysis, we examined the partnership's processes and contributions to the ordinance within the framework of Kingdon's three-stage policymaking model. We also assessed preliminary outcomes of the ordinance, including a 35% increase in produce sales and moderate declines in tobacco sales in the first four stores participating in the Tenderloin, as well as a "ripple effect," through which non-participating stores also improved their retail environments. Despite challenges, CBPR partnerships led by a strong community coalition concerned with bedrock issues like food justice and neighborhood inequities in tobacco exposure may represent an important avenue for health equity-focused research and its translation into practice.

Comparative molecular analyses of select pH- and osmoregulatory genes in three freshwater crayfish Cherax quadricarinatus, C. destructor and C. cainii.

Science.gov (United States)

Ali, Muhammad Y; Pavasovic, Ana; Dammannagoda, Lalith K; Mather, Peter B; Prentis, Peter J

2017-01-01

Systemic acid-base balance and osmotic/ionic regulation in decapod crustaceans are in part maintained by a set of transport-related enzymes such as carbonic anhydrase (CA), Na + /K + -ATPase (NKA), H + -ATPase (HAT), Na + /K + /2Cl - cotransporter (NKCC), Na + /Cl - /HCO[Formula: see text] cotransporter (NBC), Na + /H + exchanger (NHE), Arginine kinase (AK), Sarcoplasmic Ca +2 -ATPase (SERCA) and Calreticulin (CRT). We carried out a comparative molecular analysis of these genes in three commercially important yet eco-physiologically distinct freshwater crayfish , Cherax quadricarinatus, C. destructor and C. cainii , with the aim to identify mutations in these genes and determine if observed patterns of mutations were consistent with the action of natural selection. We also conducted a tissue-specific expression analysis of these genes across seven different organs, including gills, hepatopancreas, heart, kidney, liver, nerve and testes using NGS transcriptome data. The molecular analysis of the candidate genes revealed a high level of sequence conservation across the three Cherax sp. Hyphy analysis revealed that all candidate genes showed patterns of molecular variation consistent with neutral evolution. The tissue-specific expression analysis showed that 46% of candidate genes were expressed in all tissue types examined, while approximately 10% of candidate genes were only expressed in a single tissue type. The largest number of genes was observed in nerve (84%) and gills (78%) and the lowest in testes (66%). The tissue-specific expression analysis also revealed that most of the master genes regulating pH and osmoregulation (CA, NKA, HAT, NKCC, NBC, NHE) were expressed in all tissue types indicating an important physiological role for these genes outside of osmoregulation in other tissue types. The high level of sequence conservation observed in the candidate genes may be explained by the important role of these genes as well as potentially having a number of

Effects of Supplementation of Eucalyptus ( Leaf Meal on Feed Intake and Rumen Fermentation Efficiency in Swamp Buffaloes

Directory of Open Access Journals (Sweden)

N. T. Thao

2015-07-01

Full Text Available Four rumen fistulated swamp buffaloes were randomly assigned according to a 4×4 Latin square design to investigate the effects of Eucalyptus (E. Camaldulensis leaf meal (ELM supplementation as a rumen enhancer on feed intake and rumen fermentation characteristics. The dietary treatments were as follows: T1 = 0 g ELM/hd/d; T2 = 40 g ELM/hd/d; T3 = 80 g ELM/hd/d; T4 = 120 g ELM/hd/d, respectively. Experimental animals were kept in individual pens and concentrate was offered at 0.3% BW while rice straw was fed ad libitum. The results revealed that voluntary feed intake and digestion coefficients of nutrients were similar among treatments. Ruminal pH, temperature and blood urea nitrogen concentrations were not affected by ELM supplementation; however, ELM supplementation resulted in lower concentration of ruminal ammonia nitrogen. Total volatile fatty acids, propionate concentration increased with the increasing level of EML (p<0.05 while the proportion of acetate was decreased (p<0.05. Methane production was linearly decreased (p<0.05 with the increasing level of ELM supplementation. Protozoa count and proteolytic bacteria population were reduced (p<0.05 while fungal zoospores and total viable bacteria, amylolytic, cellulolytic bacteria were unchanged. In addition, nitrogen utilization and microbial protein synthesis tended to increase by the dietary treatments. Based on the present findings, it is suggested that ELM could modify the rumen fermentation and is potentially used as a rumen enhancer in methane mitigation and rumen fermentation efficiency.

Effect of Lunar Phases, Tides, and Wind Speed on the Abundance of Diptera Calliphoridae in a Mangrove Swamp.

Science.gov (United States)

Batista-da-Silva, J A

2014-02-01

Abiotic factors, such as lunar phases and tides, have a significant effect on insect development. Reproduction and immature development are usually interlinked to these abiotic factors. The tide is at its highest levels at full moon or new moon, hindering the feeding of the immature or causing their drowning. The oviposition by adult females is also compromised on these days because much of the available food is submerged. Another important abiotic factor is the wind, which displaces odoriferous particles in the air. Wind speed and direction are important elements to indicate potential sources of food for insects. I report on the effects of lunar phases, tides, and wind speed on the Calliphoridae fauna in mangrove swamps. The different species collected were identified, and the predominant species in the area were quantified. A total of 1,710 flies were collected over a 1-year period. Six Calliphoridae flies, Chloroprocta idioidea (Robineau-Desvoidy), Chrysomya megacephala (Fabricius), Chrysomya albiceps (Wiedemann), Chrysomya putoria (Wiedemann), Cochliomyia macellaria (Fabricius), and Lucilia eximia (Wiedemann) were collected. Data indicated that lunar phases have a significant effect on the abundance of C. albiceps (r = 0.39, p tides also affected the abundance of C. putoria (r = 0.40, p < 0.00), C. macellaria (r = 0.41, p < 0.00), and C. idioidea (r = 0.31, p < 0.04). The wind speed, however, did not affect these species.

Direct effects of cold shock: bioassays with three Columbia River organisms

International Nuclear Information System (INIS)

Becker, C.D.; Schneider, M.J.

1975-01-01

Results of studies of the direct effects of cold shock on the pumpkinseed sunfish (representing a warmwater fish), the rainbow trout (representing a coldwater fish), and the common crayfish showed that resistance to cold shock varies between species, is dependent on acclimation temperature, and resistance to temperature declines is dependent on the decline rate. Severe cold shock at a sublethal level is accompanied by disorientation, loss of equilibrium, and immobilization. Pumpkinseed, the warm water species, are most susceptible. Rainbow, the cold water species, are less susceptible; at an acclimation 10 0 C, rainbow survive abrupt shock to levels slightly above freezing. Crayfish, the decapod crustacean, are most resistant; at an acclimation of 15 0 C, crayfish survive abrupt shock to the point just above freezing

Importance of body-water circulation for body-heat dissipation in hot-humid climates: a distinctive body-water circulation in swamp buffaloes

Directory of Open Access Journals (Sweden)

S. Chanpongsang

2010-02-01

Full Text Available Thermo-regulation in swamp buffaloes has been investigated as an adaptive system to hot-humid climates, and several distinctive physiological responses were noted. When rectal temperature increased in hot conditions, blood volume, blood flow to the skin surface and skin temperature markedly increased in buffaloes relatively to cattle. On the other hand, the correlation between blood volume and plasma concentration of arginine vasopressin (AVP was compared between buffaloes and cattle under dehydration. Although plasma AVP in cattle increased immediately for reducing urine volume against a decrease in blood volume as well as the response observed in most animal species, the increase in plasma AVP was delayed in buffaloes, even after a large decrease in blood volume. In buffaloes, a marked increase in blood volume facilitated the dissipation of excess heat from the skin surface during wallowing. In addition, the change in plasma AVP observed in buffaloes was consistent with that of other animals living in habitats with the high availability of water. These results suggest that the thermo-regulatory system in buffaloes accelerates body-water circulation internally and externally. This system may be adaptive for heat dissipation in hot-humid climates, where an abundance of water is common.

Study of the sediment contamination levels in a mangrove swamp polluted by a marine oil spill

Energy Technology Data Exchange (ETDEWEB)

Wong, T.W.Y.; Ke, L.; Wong, Y.S.; Tam, N.F.Y. [City University of Hong Kong, Hong Kong SAR (China)

2002-07-01

The pattern of oil retention in mangrove sediments was studied in an effort to determine the temporal changes of petroleum hydrocarbon concentrations and composition several months after oil spills occur. Mangroves are inter-tidal wetlands in tropical and subtropical coastlines. Due to the anoxic and water logging characteristics of mangrove sediments, oil residues linger much longer in these wetlands compared to other coastal habitats. In November 2000, an accidental oil spill occurred in the Pearl River Estuary in which approximately 230,000 litres of crude oil was leaked from an oil tanker. The spilled oil migrated to the YiO, a typical mangrove swamp in Hong Kong Special Administrative Region. The degree of oil contamination in the sediments depended on the sediment texture and topography of the mangrove. The total petroleum hydrocarbon (TPH) concentration of the sediments in the most affected area near a freshwater creek flowing into the sea was 130 times higher than normal, one month after the accident. The mean TPH concentration was 2862 ug/g of dry sediment while the mean carbon preference index was 1.22 compared to the background value of 3.97. The temporal changes of the petroleum hydrocarbon level in 5 defined areas were examined for 7 months after the spill. The most polluted area next to the creek was determined to have very high TPH levels in the muddy sediments even 7 months after the spill. Oil residues infiltrated as deep as 20 cm into the sediments, making it more difficult to degrade than surface pollution and posing long-term adverse effects on trees in the area. It was determined that with growing industrialization and increasing demands for fuel and energy supply, mangroves in South China should be ranked as top priority for protection from oil spills. 19 refs., 6 tabs., 6 figs.

Study of the sediment contamination levels in a mangrove swamp polluted by a marine oil spill

International Nuclear Information System (INIS)

Wong, T.W.Y.; Ke, L.; Wong, Y.S.; Tam, N.F.Y.

2002-01-01

The pattern of oil retention in mangrove sediments was studied in an effort to determine the temporal changes of petroleum hydrocarbon concentrations and composition several months after oil spills occur. Mangroves are inter-tidal wetlands in tropical and subtropical coastlines. Due to the anoxic and water logging characteristics of mangrove sediments, oil residues linger much longer in these wetlands compared to other coastal habitats. In November 2000, an accidental oil spill occurred in the Pearl River Estuary in which approximately 230,000 litres of crude oil was leaked from an oil tanker. The spilled oil migrated to the YiO, a typical mangrove swamp in Hong Kong Special Administrative Region. The degree of oil contamination in the sediments depended on the sediment texture and topography of the mangrove. The total petroleum hydrocarbon (TPH) concentration of the sediments in the most affected area near a freshwater creek flowing into the sea was 130 times higher than normal, one month after the accident. The mean TPH concentration was 2862 ug/g of dry sediment while the mean carbon preference index was 1.22 compared to the background value of 3.97. The temporal changes of the petroleum hydrocarbon level in 5 defined areas were examined for 7 months after the spill. The most polluted area next to the creek was determined to have very high TPH levels in the muddy sediments even 7 months after the spill. Oil residues infiltrated as deep as 20 cm into the sediments, making it more difficult to degrade than surface pollution and posing long-term adverse effects on trees in the area. It was determined that with growing industrialization and increasing demands for fuel and energy supply, mangroves in South China should be ranked as top priority for protection from oil spills. 19 refs., 6 tabs., 6 figs

Transport and Retention of Nitrogen, Phosphorus and Carbon in North America’s Largest River Swamp Basin, the Atchafalaya River Basin

Directory of Open Access Journals (Sweden)

Y. Jun Xu

2013-04-01

Full Text Available Floodplains and river corridor wetlands may be effectively managed for reducing nutrients and carbon. However, our understanding is limited to the reduction potential of these natural riverine systems. This study utilized the long-term (1978–2004 river discharge and water quality records from an upriver and a downriver location of the Atchafalaya River to quantify the inflow, outflow, and inflow–outflow mass balance of total Kjeldahl nitrogen (TKN = organic nitrogen + ammonia nitrogen, nitrate + nitrite nitrogen (NO3 + NO2, total phosphorous (TP, and total organic carbon (TOC through the largest river swamp basin in North America. The study found that, over the past 27 years, the Atchafalaya River Basin (ARB acted as a significant sink for TKN (annual retention: 24%, TP (41%, and TOC (12%, but a source for NO3 + NO2 nitrogen (6%. On an annual basis, ARB retained 48,500 t TKN, 16,900 t TP, and 167,100 t TOC from the river water. The retention rates were closely and positively related to the river discharge with highs during the winter and spring and lows in the late summer. The higher NO3 + NO2 mass outflow occurred throughout spring and summer, indicating an active role of biological processes on nitrogen as water and air temperatures in the basin rise.

Gene cloning and induced expression pattern of IRF4 and IRF10 in the Asian swamp eel (Monopterus albus)

Science.gov (United States)

XU, Qiao-Qing; YANG, Dai-Qin; TUO, Rui; WAN, Jing; CHANG, Ming-Xian; NIE, Pin

2014-01-01

The Asian swamp eel (Monopterus albus) is one of the most economically important freshwater fish in East Asia, but data on the immune genes of M. albus are scarce compared to other commercially important fish. A better understanding of the eel’s immune responses may help in developing strategies for disease management, potentially improving yields and mitigating losses. In mammals, interferon regulatory factors (IRFs) play a vital role in both the innate and adaptive immune system; though among teleosts IRF4 and IRF10 have seldom been studied. In this study, we characterized IRF4 and IRF10 from M. albus (maIRF4 and maIRF10) and found that maIRF4 cDNA consists of 1 716 nucleotides encoding a 451 amino acid (aa) protein, while maIRF10 consists of 1 744 nucleotides including an open reading frame (ORF) of 1 236 nt encoding 411 aa. The maIRF10 gene was constitutively expressed at high levels in a variety of tissues, while maIRF4 showed a very limited expression pattern. Expression of maIRF4 and maIRF10 in head kidney, and spleen tissues was significantly up-regulated from 12 h to 48 h post-stimulation with polyinosinic: polycytidylic acid (poly I:C), lipopolysaccharide (LPS) and a common pathogenic bacteria Aeromonas hydrophila. These results suggest that IRF4 and IRF10 play roles in immune responses to both viral and bacterial infections in M. albus. PMID:25297077

Reproductive status and synchronization of oestrus for predetermined insemination of Philippine carabaos (swamp buffalo) raised by smallholder farmers

International Nuclear Information System (INIS)

Momongan, V.G.; Palad, O.A.; Singh, M.; Sarabia, A.S.; Chiong, R.D.; Nava, Z.M.; Obsioma, A.R.; Del Barrio, A.N.

1984-01-01

There is an urgent need to improve size, and meat and milk productivity of the Philippine carabao, a swamp type of water buffalo (Bubalus bubalis), through crossbreeding with the riverine type. Studies were conducted to assess the reproductive status of carabaos raised by smallholder farmers, determine conception rates of buffaloes to artificial insemination (AI) through oestrus synchronization, and examine the patterns of plasma progesterone in cyclic and acyclic carabao heifers. Approximately 20% of carabaos raised by smallholder farmers were diagnosed pregnant by rectal palpation. This low pregnancy rate may be due to a combination of factors such as the failure to submit for examination carabaos exhibiting external signs of pregnancy, the deliberate postponement of breeding for working females, the inability of bulls to gain access to carabaos in oestrus which are tethered at night, or the high incidence of anoestrus or suboestrus. The reproductive problems in non-pregnant animals were cystic (19.5%), infantile (25.7%), and dormant ovaries (51.3%), and pathology of the uterus and cervix (3.5%). Both feeding and management practices in different locations influenced the nutritional status of female carabaos examined. Animals in good body condition were either cycling or pregnant. A 30-40% conception rate was achieved by synchronization of oestrus and insemination with frozen semen at 72 and 96 h later. Based on progesterone radioimmunoassay and rectal palpation of the ovaries, anoestrus in carabao heifers was due either to a failure of cycling animals to exhibit oestrus or those with inactive ovaries. (author)

Diel turbidity cycles in a headwater stream: evidence of nocturnal bioturbation?

OpenAIRE

Cooper, Richard J.; Outram, Faye; Hiscock, Kevin M.

2016-01-01

Purpose: A small number of recent studies have linked daily cycles in stream turbidity to nocturnal bioturbation by aquatic fauna, principally crayfish, and demonstrated this process can significantly impact upon water quality under baseflow conditions. Adding to this limited body of research, we use high-resolution water quality monitoring data to investigate evidence of diel turbidity cycles in a lowland, headwater stream with a known signal crayfish (Pacifastacus leniusculus) population an...