Pasture Pond Research Articles

From small water bodies to lakes: Exploring the diversity of freshwater bacteria in an Alpine Biosphere Reserve

Small water bodies, although supporting high biodiversity, are often understudied in the Alpine region. In this work, we characterized the planktic and benthic bacterial communities, as well as the water chemistry, of a wide physiographic range of 19 freshwater bodies within an Alpine Biosphere Reserve, including ponds, pasture ponds, peat bogs, shallow lakes, and lakes. We collected both water and surface sediment samples, followed by metabarcoding analysis based on the V3-V4 regions of the 16S rRNA gene. We investigated the changes in biodiversity and the distribution of unique and shared amplicon sequence variants (ASVs) between water (11,829 ASVs) and surface sediment (19,145 ASVs) habitats, as well as across different freshwater typologies. The majority of ASVs (78 %) were unique to a single sample, highlighting the variability and uniqueness of bacterial communities in such freshwater bodies. Most freshwater environments showed higher α-diversity in sediment samples (median, 1469 ASVs) compared to water (468 ASVs). We found that water and sediment habitats harboured unique bacterial communities with significant differences in their taxonomic compositions. Benthic bacteria were associated with several biogeochemical and degradative processes occurring in the sediments, with no notable differences among freshwater typologies and with phylogenetically and ecologically similar species. Conversely, planktic communities showed greater heterogeneity: small water bodies and peat bogs were characterized by higher relative abundances of Patescibacteria (up to 33 %), while lakes and shallow lakes were dominated by Actinobacteriota (up to 36 %). Cyanobacteria (426 ASVs) were generally distributed at low abundances in both water and sediment habitats. Overall, our results provided essential insights into the bacterial ecology of understudied environments such as ponds and pasture ponds and highlighted the importance of further exploring their rich pelagic and benthic bacterial biodiversity.

Biological drivers of individual-based anuran-parasite networks under contrasting environmental conditions.

Understanding the mechanisms driving host-parasite interactions has important ecological and epidemiological implications. Traditionally, most studies dealing with host-parasite interaction networks have focused on species relationship patterns, and intra-population variation in such networks has been widely overlooked. In this study, we tested whether the composition of parasite communities of five anuran species (Leptodactylus chaquensis, Leptodactylus fuscus, Leptodactylus podicipinus, Pseudis paradoxa and Pithecopus azureus) vary across a pasture pond and a natural reserve site in south-eastern Pantanal, Brazil. We analysed the structure of individual-based networks of these five anuran species, assessed the species roles in the networks and the contribution of host species and body size to interaction strength in the networks, and tested if network ecological attributes varied between the two sites. We observed a total of 17 parasite morphospecies in 151 individual anurans and found that the abundance of parasite species tends to vary, with host species being the main filter driving parasite community structure. The composition of core parasite species remained similar between study sites, and network structure (i.e. parasite richness, interaction diversity, specialization, nestedness and modularity) did not change between pasture and natural reserve. Individual traits of hosts influenced network descriptors since larger hosts presented greater interaction strength independent of the study site. In short, we found that the occurrence of highly connected parasite taxa in both the pasture and the reserve sites may have promoted similarity in network structures, and host body size was the best predictor of associations with parasites in both study sites.

Insights into spatio-temporal dynamics of invertebrate communities from two alpine pasture ponds

This study aimed to characterise the composition, structure and trophic organisation of the macroinvertebrate communities of two pasture ponds – one natural and one artificial – in the Italian Prealps. Faunal composition was studied during the snow-free period in 2003–2004 and compared with data collected in 1984–1985. Insects (i.e., Coleoptera, Diptera and Heteroptera) prevailed (58%), followed by Tubificidae (40%). Overall, higher taxonomic diversity was assessed in the natural pond, which was less disturbed by livestock and humans. The invertebrate assemblages also had different inter- and intra-pond functional characteristics based on the substrate type (e.g., silt-mud sediments were dominated by collector-gatherers, burrowers and drought-tolerant taxa), vegetation cover and hydrological regime. The faunal composition of the two ponds was different from that reported 20 years prior due to the meteorological conditions (e.g., 2003 was exceptionally hot and dry), human activities (e.g., biomanipulation practices) and natural factors (e.g., siltation); these results emphasise the high vulnerability and resilience of alpine ponds.

Water quality of rural ponds in the extensive agricultural landscape of the Cerrado (Brazil)

The Brazilian Cerrado, one of the world’s 34 biodiversity hotspots, is today under increasing pressure from the intensification of agriculture, with the replacement of traditional extensive pastures by arable crops. Manmade ponds are currently widespread in rural areas of the Cerrado and provide many ecosystem services such as cattle watering, fish production, irrigation and erosion protection. As in other parts of the world, ponds are also likely to play a critical role in the conservation of freshwater biodiversity, although in the Cerrado there is still very little known about their biota. Good water quality, in particular the level of eutrophication, is a key factor in maintaining aquatic biodiversity at the regional scale. Therefore, we aimed here to assess the water quality of ponds in the Cerrado. We also assessed whether the main types of socioeconomic pond uses have an impact on their water quality. We focused on measures of primary production and conducted socioeconomic inquiries for 56 waterbodies in the Goiânia Cerrado region (GO, Brazil) at the beginning of the 2012 dry season. Overall, differences in water quality appeared to be linked to the type of pond use. The trophic level, as indicated by the chlorophyll concentration and conductivity, was greater in fish ponds and seemed to be related to management practices such as fish feeding and the type of water supply, in particular relatively low inflow volume. This contrasted with ponds used for cattle watering in extensive agricultural landscapes characterized by a low trophic level potentially beneficial for regional biodiversity. Good water quality in pasture ponds may be maintained by spring water inflow or heavy precipitation. Overall, the water quality of the Cerrado ponds was good compared with the same type of waterbodies in other regions of the world. These results highlight the high potential of the Cerrado ponds in extensive agricultural landscapes to provide an important habitat for aquatic biodiversity. Biodiversity inventories and assessments are now needed to increase our knowledge of these waterbodies and inform management activities at the local and regional scale.

Identifying core habitat before it’s too late: the case of Bombina variegata, an internationally endangered amphibian

Impending land-use change, including agricultural intensification, is increasingly threatening biodiversity in traditional rural landscapes. To ensure the persistence of species that are vulnerable to land-use change it is necessary to identify and protect high quality habitat before species start to decline. Given that many potentially vulnerable species are still widespread in traditional rural landscapes, it is difficult to identify particularly important locations for such species. Presence–absence data on a given species may have limited application in such cases. As an alternative to presence–absence data, we investigated the influence of environmental variables on the physiological body condition of Bombina variegata (yellow-bellied toad) in a traditional rural landscape in Transylvania, Romania. The species is internationally endangered but remains common throughout our study area. Based on body condition measurements of 550 toads from 60 ponds, we found that toads in forest ponds had significantly better body condition than those in pasture ponds, indicating that forest landscapes provided particularly high quality habitat. We suggest that measures such as body condition—in addition to distribution data—could have considerable application in identifying high quality habitat for other species that are still widespread in traditional landscapes, but have declined in modernised, but otherwise similar landscapes.

Amphibian Parasitism by the Leech Desserobdella picta at a Small Pasture Pond in Northwest Arkansas

ABSTRACT The leech Desserobdella picta was found on amphibian hosts in a small pond in Washington County, Northwest Arkansas, from February through May 1996. In addition to occurrence of D. picta, we recorded anatomical position of leech attachment on amphibians. We found D. picta on six species of amphibians, including four anurans and two salamanders, with the first documented report of the host Rana utricularia (adults and tadpoles). Desserobdella picta showed a strong preference for adult Bufo americanus with greatest attachment in the axillary region of the front limb. Adult B. americanus may not only be the preferred host of adult D. picta but also might influence dispersal of this leech.

New County Records of Amphibians and Reptiles in Kansas

New County Records of Amphibians and Reptiles in Kansas

Erosional Transport and Deposition of Plutonium and Cesium in Two Small Midwestern Watersheds

AbstractThe soils and sediments of two small watersheds and their retaining ponds were sampled in a study of the erosional transport of plutonium and cesium in midwestern ecosystems. In a watershed which had been used exclusively for row crops no relationship was observed between plutonium content of the sediments and location in the pond or clay content. In a pasture watershed sorting of the eroded material had occurred prior to entry into the pond and also within the pond. Clay content in the pasture pond sediments was significantly higher than in the soils of the surrounding watershed and increased with increasing distance from the inlet. Plutonium concentration in the sediments was strongly correlated with clay content, reflecting the higher plutonium content of finer soil particles. Cesium behaved similarly to plutonium in the soils and sediments of both watersheds. Where sorting occurs, as in the pasture watershed, deposits of fine sediments will contain higher plutonium and cesium concentrations than in the original surface soil.

Water Chemistry and Plankton in Unfertilized Ponds in Pastures and in Woods

Abstract Unfertilized ponds in pastures are more eutrophic than unfertilized ponds in woods. Fertilizer application rates currently used in bass-sunfish ponds in the southeastern United States may be greatly reduced in many pasture ponds.

Phosphorus and Potassium Fertilization of Sunfish Ponds

Abstract The rate of fertilization with P2O5, 9 kg/hectare/application, currently recommended for woodland ponds stocked with largemouth bass and sunfish was reduced by one-half without significant reduction in sunfish production. Although further experiments need to be conducted with combinations of largemouth bass and sunfish, these results may be applied on a trial basis. Ponds with waters softer than 20 mg/liter total alkalinity and bottom muds more acid than pH 5.8 should be limed if P2O5 application rates are reduced to 4.5 kg/hectare. Results of the present study probably will not apply to pasture ponds, which usually are more eutrophic than ponds on wooded watersheds. Potash apparently can be omitted from pond fertilizers without reduction in fish production, although this practice is not suggested for waters with less than 1.3 mg/liter potassium.