Temporary Water Bodies Research Articles

Knowledge, attitude and practices in relation to prevention and control of schistosomiasis infection in Mwea Kirinyaga county, Kenya.

BackgroundSchistosomiasis remains a major public health problem in Kenya. Inadequate knowledge, attitudes and practices (KAP) on causative factors are some of the critical factors for the increased prevalence. The study assessed KAP on the control and prevention of schistosomiasis infection in Mwea division, Kirinyaga County-Kenya. Four hundred and sixty five house-hold heads were enrolled in this study by use of simple random sampling technique.MethodsThe study employed an analytical descriptive cross sectional design utilizing both quantitative and qualitative data collection methods. A pretested structured questionnaire, Focus Group Discusions (FGDs) and Key Informant Interviews (KII) guides were used for data collection. Descriptive statistics and Chi square tests and Fisher’s exact tests were computed where applicable. Data from the FGDs and KIIs were analyzed using NUID.IST NUIRO.6 software.ResultsSignificant associations between knowledge and demographic factors i.e. age (p = 0.011), education level (p = 0.046), were reported. Handwashing after visiting the toilet (p = 0.001), having a toilet facility at home (p = 0.014); raring animals at home (p = 0.031), households being affected by floods (p = 0.005) and frequency of visits to the paddies (p = 0.037) had a significant association with respondents practices and schistosomiasis infection. Further significance was reported on households being affected by floods during the rainy season (p < 0.001), sources of water in a household (p < 0.047) and having a temporary water body in the area (p = 0.024) with increase in schistosomiasis infection. Results revealed that respondents practices were not significantly associated with gender (p = 0.060), marital status (p = 0.71), wearing of protective gear (p = 0.142) and working on the paddies (p = 0.144).ConclusionsThis study reveals that knowledge about the cause, transmission, symptoms and prevention of schistosomiasis among the Mwea population was inadequate, and that this could be a challenging obstacle to the elimination of schistosomiasis in these communities. Due to various dominant risk factors, different control strategies should be designed. Therefore, there is a need for integrated control programme to have a lasting impact on transmission of schistosomiasis infection. Control programs like mass drug administration need to go beyond anti-helminthic treatment and that there is a need of a more comprehensive approach including access to clean water, sanitation and hygiene. School and community-based health education is also imperative among these communities to significantly reduce the transmission and morbidity from schistosomiasis.

Use of Reproductive Microhabitat by Melanophryniscus montevidensis (Anura: Bufonidae) from Uruguay.

This study describes the reproductive microhabitat of Melanophryniscus montevidensis and its use in two water bodies (WBs) in Barra de la Laguna de Rocha, Uruguay. Monthly field trips were performed between March 2012 and February 2013. Variables related to the WBs and vegetation, as well as parameters linked to the usage the amphibians make of the site (e.g: distance to the border of the pond, water depth and the vegetation use) were recorded. The behavior shown by the individuals during the breeding activity was recorded. This activity occurs in shallow temporary WBs with abundant hydrophilic vegetation. The individuals were found more frequently in areas near the edge of the pond, which has denser vegetation. The calling males were found closer to the border of the pond, and they showed better body condition than the non-calling males. In addition to calling activities, males used alternative tactics to find couples, such as active search of females, and aggressive behaviors, such as male displacing and physical combat. Such behaviors are common in anurans with explosive reproductive dynamics. The characterization of the reproductive microhabitats permits the proposal of strategies for the conservation of the species in Uruguay, given that the loss and fragmentation of habitats is one of the main causes considered for the decrease in their populations.

Mosquito breeding site water temperature observations and simulations towards improved vector-borne disease models for Africa.

An energy budget model is developed to predict water temperature of typical mosquito larval developmental habitats. It assumes a homogeneous mixed water column driven by empirically derived fluxes. The model shows good agreement at both hourly and daily time scales with 10-min temporal resolution observed water temperatures, monitored between June and November 2013 within a peri-urban area of Kumasi, Ghana. There was a close match between larvae development times calculated using either the model-derived or observed water temperatures. The water temperature scheme represents a significant improvement over assuming the water temperature to be equal to air temperature. The energy budget model requires observed minimum and maximum temperatures, information that is generally available from weather stations. Our results show that hourly variations in water temperature are important for the simulation of aquatic-stage development times. By contrast, we found that larval development is insensitive to sub-hourly variations. Modelling suggests that in addition to water temperature, accurate estimation of degree-day development time is very important to correctly predict the larvae development times. The results highlight the potential of the model to predict water temperature of temporary bodies of surface water. Our study represents an important contribution towards the improvement of weatherdriven dynamical disease models, including those designed for malaria early forecasting systems.

First report of Leptolegnia chapmanii (Peronosporomycetes: Saprolegniales) affecting mosquitoes in central Brazil

Numerous isolates of an oomycete ‘fungus’, Leptolegnia chapmanii, are reported from Brazil for the first time. This aquatic pathogen was baited with Aedes aegypti sentinel larvae from stagnant, temporary bodies of water in selected locations under secondary tropical forest in and near the central Brazilian city of Goiânia and from more distant sites in the western and northern regions of the state of Goiás. Isolates were identified based on their morphological and developmental characters, comparative sequence data for the ITS and TEF loci, as well as their rapid activity against A. aegypti larvae. Taxonomic issues affecting the application of the name L. chapmanii and its typification are rectified. This study contributes to a better understanding of the presence and distribution of this oomycete in Brazil, its sequence-based identification, and of its potential as a biological agent against mosquito vectors.

The role of spatial environmental factors as determinants of large branchiopod distribution in Tunisian temporary ponds

The influence of spatial and environmental factors in explaining the structure of large branchiopod assemblages at different spatial scales is still poorly explored. We hypothesized that the extent of actual spatial connectivity, and thus the spatial distribution of a metacommunity, may depend on the environmental conditions as represented by climatic gradients and the structural characteristics of the landscape. To test this hypothesis, the distributional patterns of 14 large branchiopod species in a set of 177 temporary water bodies repeatedly sampled across Tunisia and on its main islands were analysed. Physical, chemical, morphological and climatic characteristics of the studied water bodies were collected as well, and spatial structures were described using distance-based Moran’s Eigenvector Maps. Distance-based Redundancy Analysis and variance partitioning explained more than one-half of total variation. Mantel’s autocorrelograms demonstrated that species composition was spatially autocorrelated at shorter distances in the Mediterranean part of the country than in the southern, more arid part. These results suggest that both dispersal limitation and species response to spatially structured environmental gradients might be involved in determining large branchiopod distribution in Tunisia and that these patterns may greatly vary on a regional basis.

Taphonomic phenomenon of ancient hair from Glacial Beringia: perspectives for palaeoecological reconstructions

An accumulation of mammoth hair, discovered in the Bol'shaya Chukochya River valley (northeast Yakutia, Russia), was found to contain remains of terrestrial and aquatic organisms, including plants, insects, crustaceans, birds and mammals. Radiocarbon dating indicated that this post‐mortem taphocoenosis represented multiple time periods. The mammoth hair was dated to older than 45 ka BP, the plants were dated to 12 750±50 a BP (which corresponds to a shift in the environmental conditions and landscapes during the formation of thermokarst in northeastern Russia) and the bird feathers were dated to 4115±40 a BP. A scenario of the formation of this fossil assemblage is proposed, covering the MIS 3‐1 time range. The hair also yielded various Arctic branchiopod crustaceans, which inhabit shallow temporary water bodies and therefore are important for reconstruction of palaeoenvironments. The cladoceran subgenus Daphnia (Ctenodaphnia), currently absent from the Asian part of Beringia, is reported from this region for the first time. The study demonstrates that the discovered permafrost‐preserved hair is a unique repository of Ice Age organisms.

Sex-specific functional responses of dragonfly naiads Rhodothemis rufa on Culex quinquefasciatus larvae in laboratory bioassay

ABSTRACTLaboratory bioassay was conducted to establish the biocontrol potentiality of naiads (aquatic nymphal stage) of Rhodothemis rufa (Rambur, 1842) against larvae of Culex quinquefasciatus, a common vector of filariasis in Tropical countries. From the study, it was noticed that in laboratory condition, the rate of predation of males of R. rufa was higher than that of females of almost same size and same species. The results of the present study revealed that both sexes displayed a density-dependent decelerating type-II functional response as the logistic regression estimated a significant negative linear parameter (P1 value of −0.330 and −0.151 for males and females, respectively). Attack rate was almost similar for both sexes (0.082); however, handling time is less in males (0.62 min) than in females (0.852 min). The predator species usually coexist in the same aquatic habitat to that of mosquito larvae and can be effectively used in field condition to reduce the larval densities of mosquitoes in temporary or permanent aquatic water bodies.

A floristic inventory of the epizoic algae and their associates from inland waters of Bangladesh

The diversity of epizoic algae and their associates occurring on the body surface of aquatic animals in 35 permanent and 15 temporary lentic water bodies of Rajshahi University, Bangladesh and its adjacent area has been studied. In all 35 genera and 82 species have been recorded of which 16 genera and 51 species belonged to Chlorophyceae, 11 genera and 21 species to Cyanophyceae, seven genera and nine species to Bacillariophyceae and one genus and species to Euglenophyceae. The environmental parameters at which the epizoic algae occurred were a pH of 7.4–8.2 and a water temperature of 19.4–32.1°C.

The First Bromeligenous Species of Dendropsophus (Anura: Hylidae) from Brazil's Atlantic Forest.

We describe a new treefrog species of Dendropsophus collected on rocky outcrops in the Brazilian Atlantic Forest. Ecologically, the new species can be distinguished from all known congeners by having a larval phase associated with rainwater accumulated in bromeliad phytotelms instead of temporary or lentic water bodies. Phylogenetic analysis based on molecular data confirms that the new species is a member of Dendropsophus; our analysis does not assign it to any recognized species group in the genus. Morphologically, based on comparison with the 96 known congeners, the new species is diagnosed by its small size, framed dorsal color pattern, and short webbing between toes IV-V. The advertisement call is composed of a moderate-pitched two-note call (~5 kHz). The territorial call contains more notes and pulses than the advertisement call. Field observations suggest that this new bromeligenous species uses a variety of bromeliad species to breed in, and may be both territorial and exhibit male parental care.

The mineralisation of dissolved organic matter recovered from temperate waterbodies during summer

Natural dissolved organic matter (DOM) has many forms in freshwaters, controlling C availability for heterotrophic respiration and ecosystem functions in headwaters and downstream ecosystems. This study aimed to examine the respiration of DOM recovered using reverse osmosis (RO) during extended summer baseflow from a parkland Pond (DOMPond) and three headwater rivers: moorland (DOMMoor), mixed agriculture (DOMAgr) and predominantly moorland system with mixed riparian forest (DOMForest), and compared to glucose and soil-derived fulvic acid. Batch decomposition tests at time points up to 379 h were completed in a replicated 96-well micro-plate system (MicroResp) spiking river sediments carrying a standardised microbial inoculum with C sources at two concentrations (1513 and 30 µgC/g sediment dry matter). Respiration rates were greatest initially and declined over time with an exponential form. Total C respired (38–80 %, following subtraction of basal respiration controls) for the high C treatment followed: DOMForest > DOMAgr > DOMMoor > DOMPond > Fulvic acid. A similar order occurred at the low C treatment but BDOC >100 % was evidence that added DOM primed respiration of the sediment C above that of basal controls. Despite issues of high background salt concentrations in the DOM matrix caused by the RO procedure results show that even under summer baseflow conditions DOM can be highly labile. Labile C generated especially from agricultural catchments and those with riparian forests may be conveyed downstream to fresh and estuarine waters to control ecological processes at critical times of the year.

Rising temperatures may increase growth rates and microcystin production in tropical Microcystis species

Rising temperatures (1.4–6°C) due to climate change have been predicted to increase cyanobacterial bloom occurrences in temperate water bodies; however, the impacts of warming on tropical cyanobacterial blooms are unknown. We examined the effects of four different temperatures on the growth rates and microcystin (MC) production of five tropical Microcystis isolates (M. ichthyoblabe (two strains), M. viridis, M. flos-aquae, and M. aeruginosa). The temperature treatments are based on current temperature range in Singapore's reservoirs (27°C and 30°C), as well as projected mean (33°C) and maximum temperatures (36°C) based on tropical climate change estimates of +6°C in air temperature. Increasing temperatures did not significantly affect the maximum growth rates of most Microcystis strains. Higher growth rates were only observed in one M. ichthyoblabe strain at 33°C and M. flos-aquae at 30°C where both were isolated from the same reservoir. MC-RR and MC-LR were produced in varying amounts by all four species of Microcystis. Raised temperatures of 33°C were found to boost total MC cell quota for three Microcystis strains although further increase to 36°C led to a sharp decrease in total MC cell quota for all five Microcystis strains. Increasing temperature also led to higher MC-LR:MC-RR cell quota ratios in M. ichthyoblabe. Our study suggests that higher mean water temperatures resulting from climate change will generally not influence growth rates of Microcystis spp. in Singapore except for increases in M. ichthyoblabe strains. However, toxin cell quota may increase under moderate warming scenarios depending on the species.

Stochastic effects associated with resting egg banks lead to genetically differentiated active populations in large branchiopods from temporary water bodies

For Branchiopoda (Crustacea) and other taxa with resting egg banks, genetic differentiation among populations has been commonly observed at small geographic scales. This has been explained by a combination of priority effects and local adaptation. However, stochastic effects associated with hatching from resting egg banks may distort estimates of genetic differentiation. Herein we assessed the genetic composition and differentiation of subsequent active populations of two spinicaudatan species within a temporary water body in eastern Australia by sequencing mitochondrial cytochrome c oxidase subunit I and compared it to the differentiation among populations. Furthermore, a simulation was performed in which the genetic differentiation between active populations derived from resting egg banks of identical genetic composition was assessed. Genetic differentiation between subsequent active populations of the same water body was significant and of similar magnitude as among neighboring populations, all simulated active populations were significantly differentiated from each other. Stochastic effects associated with hatching from resting egg banks combined with genetic drift can lead to significantly differentiated active populations, even if the genetic composition of their resting egg banks was identical. As a consequence, genetic differentiation among populations may often be overestimated due to stochastic effects, which in turn may result in underestimations of gene flow.

Macroinvertebrates in woodland pools and ditches and their response to artificial drainage in Estonia

Since the twentieth century, freshwater ecosystems have been extensively drained. Despite the magnitude of artificial drainage, its impact on freshwater biodiversity, especially on small forest waterbodies, is still poorly known. We examined macroinvertebrate taxon richness and assemblages in forest landscapes, comparing natural temporary waterbodies situated in drained and undrained areas, ditches, and wheel rut pools. We aimed to determine macroinvertebrates that are characteristic to these waterbodies, the impact of forest drainage on them, and the functioning of ditches as an alternative habitat for aquatic macroinvertebrates. Altogether 181 waterbodies within six landscape regions were surveyed, identifying 171 macroinvertebrate taxa. Taxa accumulation curves pooling all the regions indicated that natural waterbodies situated in drained areas harbored less invertebrate taxa than other waterbody types. Thus drainage has effect at supraregional scale. At the waterbody scale, however, we did not detect substantial forest drainage effect on taxon richness or assemblages. Ordering of the waterbody types by richness differed between landscape regions, suggesting that macroinvertebrates are largely dependent on landscape characteristics. Since neither total and mean richness nor assemblages did not differ significantly between natural temporary waterbodies and drainage ditches, the latter could be considered as an alternative habitat for invertebrates at least in semi-naturally managed forests.

Documenting the fauna of a small temporary pond from Pune, Maharashtra, India

Most of the limnological studies in India have focussed on a few taxa of large, permanent water bodies, and pond ecosystems, and related temporary water bodies are neglected. We present here a faunal inventory, with representative photographs, for a single, small temporary pond, reporting over 125 species of strictly aquatic fauna and 25 species of associated fauna, even though we did not identify some groups such as Protozoa, Diptera and nymphs of Odonata, etc. The identified species belong to seven taxa of vertebrates and invertebrates together. Arthropoda and Rotifera were the most species rich groups, observed with 83 and 45 representatives, respectively. Coleoptera were the most numerous in terms of species number. Such a small water body holds some endemics as well as otherwise very rare animals and so deserves better attention. We also highlight the potential and importance of such habitats for research and conservation.

Scinax nebulosus (Spix, 1824) (Amphibia: Hylidae): review of distribution and new record from Sergipe, Brazil

We present the first record of Scinax nebulosus for the State of Sergipe, in the Atlantic Forest, Brazil. Scinax nebulosus is a small hylid which inhabits the Amazon and Atlantic Forest. Its main microhabitat is temporary water bodies in tropical forests. This species can be recognized by the presence of many scattered glandules on the dorsal surface, especially on the head, upper eyelids and margins of the members. Some taxonomic studies and vocals records suggest careful evaluation of the taxonomic status of S. nebulosus along its geographical distribution.

From the bush to the bench: the annual Nothobranchius fishes as a new model system in biology.

African annual fishes from the genus Nothobranchius are small teleosts that inhabit temporary water bodies subject to annual desiccation due to the alternation of the monsoon seasons. Given their unique biology, these fish have emerged as a model taxon in several biological disciplines. Their increasing popularity stems from the extremely short lifespan that is the result of their specific life-history adaptations and is retained under laboratory conditions. Nothobranchius furzeri, the most popular laboratory species, is the vertebrate species with the shortest lifespan recorded in captivity. In the laboratory, adults of different Nothobranchius species and populations live between 3 and 18 months and, notably, there is a negative correlation between the captive lifespan of a species and the aridity of their habitat. Their short lifespan is coupled to rapid age-dependent functional decline and expression of cellular and molecular changes comparable to those observed in other vertebrates, including humans. The recent development of transgenesis in this species makes it possible to insert specific constructs into their genome, and the establishment of transgenic lines is facilitated by their very rapid generation time, which can be as short as 1 month. This makes Nothobranchius species particularly suited for investigating biological and molecular aspects of ageing and ageing-associated dysfunctions. At the same time, they also represent a unique model taxon to investigate the evolution of life-history adaptations and their genetic architecture. We review their natural history, including phylogenetic relationships, distribution in relation to habitat conditions and natural selection for differential longevity, population structure and demography, and life cycle with emphasis on diapause that may occur at three stages during embryonic development. We further critically evaluate their use as a laboratory model for understanding the evolution of a rapid ageing rate and its consequences for other life-history traits, for cellular, molecular and integrative traits associated with the ageing process, high incidence of neoplasias, their utility for genome-wide gene-expression studies, and as a model for quantitative genetics. We summarize recent achievements in fostering Nothobranchius species as a widely applicable model system, including an annotated transcriptome, successful transgenesis, and existence of viable inbred lines. We compare the conditions they experience in the wild and in captivity and suggest that they are an ideal taxon to investigate natural genetic variation in a laboratory setting. We conclude that Nothobranchius species - and N. furzeri in particular - could become a unique model taxon that bridges interests in ecological and biomedical research. We hope that a conceptual and methodological integration of these two branches of biology will provide important new insights.

Hatching phenology of Odonata species inhabiting temporary and permanent water bodies (Odonata: Lestidae, Aeshnidae, Libellulidae)

The hatching phenology of 15 Odonata species was studied under seminatural conditions to find out how the hatching modes of typical species of summer dry temporary waters (vernal ponds) differ from those of species inhabiting both permanent and temporary waters. We attempt to answer the following questions. (1) Do vernal pond species hatch earlier in the year than congeneric permanent water species? (2) Can hatching in vernal pond species be delayed under unsuitable environmental conditions, like drought? (3) Can eggs of vernal pond species survive for more than one year? Larvae of vernal pond species, Aeshna affinis, Lestes barbarus, L. dryas and Sympetrum flaveolum, hatched significantly earlier than their permanent water counterparts A. mixta, L. sponsa, L. virens, L. viridis, S. danae, S. depressiusculum, S. meridionale, S. sanguineum, S. striolatum and S. vulgatum. Only one vernal pond species, L. macrostigma, did not show this early hatching. In both vernal pond and permanent water species hatching ...

Long-term monitoring of astatic water bodies: microcrustaceans as indicators of hydroperiod length in ponds and pools

Microcrustacean assemblages (Cladocera and Copepoda) from astatic ponds and pools of Castelporziano Presidential Estate were analysed to evaluate their role as indicators of functional variations related to the duration of the wet phase. Samples from a subset of 23 water bodies classified as permanent or temporary (based on observations over two decades, 1989–2010) were analysed. As a whole, 36 species of microcrustaceans were present. Hierarchical clustering allowed a clear distinction between temporary and permanent water bodies. Principal coordinates analysis (PCoA) provided a good separation of the two major hydroperiod groups along the first axis, while no correlation emerged among PCoA axes and hydrogeological setting. The correlation between species and the first PCoA axis highlighted biological indicators of hydrological change: among them, the cyclopoid copepods Macrocyclops albidus and Eucyclops serrulatus, which have no resting stages, were exclusive of permanent ponds; the calanoid copepod Eudiaptomus padanus etruscus and the cladocerans Ceriodaphnia reticulata, Scapholeberis rammneri and Coronatella rectangula were present in permanent and semi-permanent ponds; the cladoceran Daphnia chevreuxi and the calanoid copepods Diaptomus serbicus, Hemidiaptomus gurneyi and Mixodiaptomus kupelwieseri were exclusive of temporary ponds with short hydroperiod (less than 6 months). Temporary water bodies hosted a higher mean species richness (13.7 species) than permanent ones (10.3), and the difference was statistically significant. Our results highlight that: (1) the cladoceran and copepod assemblage effectively discriminate between ponds with different wet phase duration, proving to be good bioindicator; (2) small astatic water bodies play an important role in biodiversity conservation, as they host a high percentage of the species distributed over wider areas, next to species which are exclusively found in these habitats; (3) hydroperiod appears to be the main driving force in characterising microcrustacean assemblages in astatic ponds.

Phytoplankton succession in an artificial, periodically drained small water body

This study was undertaken to monitor the course of a secondary succession of phytoplankton in temporary water bodies, based on a man-made periodically drained pond. Results of phycological analyses showed, that small Chlorophyceae from the order Chlorococcales predominated qualitatively throughout the study period. Chlorophyceae, e.g. stress-resistant Haematococcus pluvialis, developed best as the first al - gae (after the pond was re-filled). In the next stages of diatom succession ( Ulnaria ulna) predominated quan- titatively, followed by the longest period of Cyanobacteria (Aphanothece elabens) predominance, replaced again by Chlorophyceae (Tetraedron minimum and Oocystis lacustris). Total abundance of algae, similarly as that of Cyanobacteria, were positively correlated with temperature and pH of water.

Tropical cyanobacterial blooms: a review of prevalence, problem taxa, toxins and influencing environmental factors

Toxic cyanobacterial blooms are a major issue in freshwater systems in many countries. The potentially toxic species and their ecological causes are likely to be different in tropical zones from those in temperate water bodies; however, studies on tropical toxic cyanobacterial blooms are sporadic and currently there is no global synthesis. In this review, we examined published information on tropical cyanobacterial bloom occurrence and toxin production to investigate patterns in their growth and distribution. Microcystis was the most frequently occurring bloom genus throughout tropical Asia, Africa and Central America, while Cylindrospermopsis and Anabaena blooms occurred in various locations in tropical Australia, America and Africa. Microcystis blooms were more prevalent during the wet season while Cylindrospermopsis blooms were more prevalent during the dry period. Microcystin was the most encountered toxin throughout the tropics. A meta-analysis of tropical cyanobacterial blooms showed that Microcystis blooms were more associated with higher total nitrogen concentrations, while Cylindrospermopsis blooms were more associated with higher maximum temperatures. Meta-analysis also showed a positive linear relationship between levels of microcystin and N:P (nitrate:phosphate) ratio. Tropical African Microcystis blooms were found to have the lowest microcystin levels in relation to biomass and N:P (nitrate:phosphate) compared to tropical Asian, Australian and American blooms. There was also no significant correlation between microcystin concentration and cell concentration for tropical African blooms as opposed to tropical Asian and American blooms. Our review illustrates that some cyanobacteria and toxins are more prevalent in tropical areas. While some tropical countries have considerable information regarding toxic blooms, others have few or no reported studies.