scholarly journals Managing human mediated range shifts: understanding spatial, temporal and genetic variation in marine non- native species

2021 ◽  
Author(s):  
Luke E Holman ◽  
Shirley Parker-Nance ◽  
Mark de Bruyn ◽  
Simon Creer ◽  
Gary Carvalho ◽  
...  
Keyword(s):  
Native Species ◽  
Temporal Dynamics ◽  
Methodological Approach ◽  
Environmental Dna ◽  
Range Size ◽  
Range Shifts ◽  
Spatial And Temporal Variation ◽  
Tissue Samples ◽  
Molecular Biodiversity ◽  
Biodiversity Changes

The use of molecular methods to manage natural resources is increasingly common. However, DNA-based methods are seldom used to understand the spatial and temporal dynamics of species' range shifts. This is important when managing range-shifting species such as non-native species (NNS), which can have negative impacts on biotic communities. Here we investigated the range-shifting NNS Ciona robusta, Clavelina lepadiformis, Microcosmus squamiger and Styela plicata using a combined methodological approach. We first conducted non-molecular biodiversity surveys for these NSS along the South African coastline, and compared the results with historical surveys. We detected no consistent change in range size across species, with some displaying range stability and others showing range shifts. We then sequenced a section of cytochrome c oxidase subunit I (COI) from tissue samples and found genetic differences along the coastline but no change over recent times. Finally, we found that environmental DNA metabarcoding data showed broad congruence with both the non-molecular biodiversity and the COI datasets, but failed to capture complete incidence of all NSS. Overall, we demonstrated how a combined methodological approach can effectively detect spatial and temporal variation in genetic composition and range size, which is key for managing biodiversity changes of both threatened and NSS.

scholarly journals Spatial distribution and temporal variation of microcrustaceans assembly (Cladocera and Copepoda) in different compartments of a reservoir in the brazilian semiarid region

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Josiane Souza Santos ◽  
Nadson Ressyé Simões ◽  
Sérgio Luiz Sonoda
Keyword(s):  
Spatial Distribution ◽  
Spatial Variation ◽  
Temporal Variation ◽  
Aquatic Macrophytes ◽  
Temporal Dynamics ◽  
Lateral Compartment ◽  
Spatial And Temporal Variation ◽  
Semiarid Region ◽  
Brazilian Semiarid ◽  
Significant Spatial Variation

Abstract Aim: The objective of this study was to investigate the spatial and temporal variation of microcrustacean assemblages of a reservoir in the Brazilian semiarid region. Methods Physical and chemical water variables and samples of microcrustaceans were collected at eight sites of the reservoir between July 2013 and November 2014, in a total of seven campaigns. For this study, the reservoir was categorized in two compartments: lateral and central. Results Limnological variables showed significant temporal variation (PERMANOVA, Pseudo-F = 19.51, p = 0.001). Higher turbidity values and suspended solids were observed in the rainiest months, while during the dry months, we measured higher values of transparency, dissolved oxygen, and chlorophyll-a. It was not found significant spatial variation of limnological variables (PERMANOVA, Pseudo-F = 0.96; p = 0.394). During the study period, ten species were recorded: four Cladocera (Ceriodaphnia cornuta, Daphnia gessneri, Diaphanosoma birgei and Diaphanosoma spinulosum ) three Copepoda Calanoida (Argyrodiaptomus azevedoi, Notodiaptomus cearensis and Notodiaptomus iheringi) and three Copepoda Cyclopoida (Macrocyclops albidus, Thermocyclops minutus and Thermocyclops decipiens). The microcrustacean assemblages showed significant temporal variation (PERMANOVA, Pseudo-F = 4.34; p = 0.001) as well as significant spatial variation (PERMANOVA, Pseudo-F = 9.46; p = 0.001). The highest values of abundance and richness were observed in the lateral compartment, this result is mainly related to the presence of aquatic macrophytes in this region, because the analysis of partial RDA indicated that limnological variables explained only 11% of this variation (Pseudo-F = 2.08, p = 0.001). Conclusions The results suggest that the seasonality of the semiarid is an important factor in the temporal dynamics of the limnological variables, while the aquatic macrophytes play an important role in the spatial distribution of the microcrustacean assembly.

scholarly journals Spatial and Temporal Variations of Nitrogen and Phosphorus in Surface Water and Groundwater of Mudong River Watershed in Huixian Karst Wetland, Southwest China

2021 ◽  
Vol 13 (19) ◽  
pp. 10740
Author(s):  
Linyan Pan ◽  
Junfeng Dai ◽  
Zhiqiang Wu ◽  
Liangliang Huang ◽  
Zupeng Wan ◽  
...  
Keyword(s):  
Surface Water ◽  
Temporal Dynamics ◽  
Flow Direction ◽  
Influencing Factor ◽  
Shallow Groundwater ◽  
Temporal Variations ◽  
Field Investigation ◽  
Spatial And Temporal Variation ◽  
Nitrogen And Phosphorus ◽  
River Watershed

When considering the factors affecting the spatial and temporal variation of nitrogen and phosphorus in karst watersheds, the unique karst hydrogeology as an internal influencing factor cannot be ignored, as well as natural factors such as meteorological hydrology and external factors such as human activities. A watershed-scale field investigation was completed to statistically analyze spatial and temporal dynamics of nitrogen and phosphorus through the regular monitoring and collection of surface water and shallow groundwater in the agricultural-dominated Mudong River watershed in the Huixian Karst Wetland over one year (May 2020 to April 2021). Our research found that non-point source pollution of nitrogen (84.5% of 239 samples TN > 1.0 mg/L) was more serious than phosphorus (7.5% of 239 samples TP > 0.2 mg/L) in the study area, and shallow groundwater nitrogen pollution (98.3% of 118 samples TN > 1.0 mg/L) was more serious than surface water (68.6% of 121 samples TN > 1.0 mg/L). In the three regions with different hydrodynamic features, the TN concentration was higher and dominated by NO3−-N in the river in the northern recharge area, while the concentrations of TN and TP were the highest in shallow groundwater wells in the central wetland core area and increased along the surface water flow direction in the western discharge area. This research will help improve the knowledge about the influence of karst hydrodynamic features on the spatial patterns of nitrogen and phosphorus in water, paying attention to the quality protection and security of water in karst areas with a fragile water ecological environment.

Assessing variation in assemblages of large marine fauna off ocean beaches using drones

2020 ◽  
Vol 71 (1) ◽  
pp. 68 ◽  
Author(s):  
Brendan P. Kelaher ◽  
Andrew P. Colefax ◽  
Alejandro Tagliafico ◽  
Melanie J. Bishop ◽  
Anna Giles ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Bottlenose Dolphins ◽  
Spatial And Temporal Variation ◽  
Marine Animals ◽  
Marine Fauna ◽  
South Wales ◽  
Carcharhinus Leucas ◽  
Spatio Temporal ◽  
Marine Wildlife

The turbulent waters off ocean beaches provide habitat for large marine fauna, including dolphins, sharks, rays, turtles and game fish. Although, historically, these assemblages have proven difficult to quantify, we used a new drone-based approach to assess spatial and temporal variation in assemblages of large marine fauna off four exposed beaches in New South Wales, Australia. In total, 4388 individual large marine animals were identified from 216 drone flights. The most common taxa, bottlenose dolphins (Tursiops spp.) and Australian cownose rays (Rhinoptera neglecta), occurred in 25.5 and 19.9% of flights respectively. White (Carcharodon carcharias), bull (Carcharhinus leucas) and other whaler (Carcharhinus spp.) sharks were observed in <1% of flights. There was significant variation in the structure of assemblages of large fauna among beaches, with those adjacent to riverine estuaries having greater richness and abundance of wildlife. Overall, drone surveys were successful in documenting the spatio-temporal dynamics of an impressive suite of large marine fauna. We contend that emerging drone technology can make a valuable contribution to the ecological information required to ensure the long-term sustainability of sandy-beach ecosystems and associated marine wildlife.

scholarly journals Assessment of the Impacts of Anthropogenic Activities on a Large River Using Longfin Eel as a Bioindicator

2020 ◽  
Vol 12 (20) ◽  
pp. 8412
Author(s):  
Olivier Champeau ◽  
James M. Ataria ◽  
Grant L. Northcott ◽  
Gen Kume ◽  
Andrew Barrick ◽  
...  
Keyword(s):  
Native Species ◽  
Anthropogenic Activities ◽  
Economic Value ◽  
River System ◽  
Large River ◽  
Chemical Contamination ◽  
Bioindicator Species ◽  
Tissue Samples ◽  
Anthropogenic Stressors ◽  
Residential Land Use

The Matāura River is the sixth largest river system in New Zealand and has long been subject to agricultural, industrial, and residential land use activities. The catchment has economic value and is of great cultural importance for local Māori, who have concerns over potential adverse impacts that anthropogenic stressors exert on the health of the river. There is a dearth of information on the impacts of these stressors towards the health of native species such as the longfin eel Anguilla dieffenbachii. This study assessed the environmental status of the Matāura River using biological and chemical methodologies incorporating A. dieffenbachii as a bioindicator species for exposure to multiple anthropogenic stressors. A range of biomarkers were measured in caged and wild-caught eels (when available) to characterize site-specific responses to anthropogenic stressors. While there was no clear indication of cumulative impacts moving from pristine headwaters to the lower reaches of the Matāura River, biomarkers of xenobiotic metabolization were induced in A. dieffenbachia and there was evidence of chemical contamination in sediment and tissue samples.

Biological, Ecological, and Distributional Aspects of Two Native Species of Lucilia Genus (Diptera: Calliphoridae) of Forensic Interest in Yungas Environments of Argentina

2020 ◽  
Vol 57 (6) ◽  
pp. 1700-1711
Author(s):  
X Acosta ◽  
A X González-Reyes ◽  
N D Centeno ◽  
J A Corronca
Keyword(s):  
Native Species ◽  
Temporal Dynamics ◽  
Synergistic Effects ◽  
Habitat Preferences ◽  
Warm Season ◽  
Sun Exposure ◽  
Late Summer ◽  
Cold Season ◽  
Tree Cover ◽  
Native Habitats

Abstract This study determined the spatial and temporal dynamics of two native neotropical species flies of forensic interest, belonging to the Lucilia (Robineau-Desvoidy) genus. The study focused on their abundance and reproductive behaviors associated with different habitats and phenological parameters. In the Province of Salta, Argentina, monthly samplings were performed over 1 yr in urban, rural, and native habitats, at morning, mid-day, and afternoon periods, controlling the oviposition of captured specimens. Environmental variables were also assessed: cloudiness, precipitation, relative humidity, temperature, and tree cover. Lucilia purpurascens (Walker) appeared to be associated with native habitats, whereas Lucilia ochricornis (Wiedemann) was mainly associated with rural habitats, exhibiting distinct habitat preferences. Two ecotones were also identified: rural–urban and rural–native, suggesting rural habitats promoted habitable conditions at its margins. Both species were recorded at the end of winter to the middle of autumn, with an initial peak in early spring, and a second peak at late summer. These peaks were associated with the highest numbers of laid eggs. Lucilia purpurascens preferred high tree coverings, whereas L. ochricornis resisted areas with intermediate sun, suggesting limited sun exposure was important. The latter was also associated with daily flight activities; during the warm season, the densest catches occurred at morning and afternoon periods, whereas during the cold season, they occurred at mid-day. Climatic variables explained 77% of variability in terms of abundance and oviposition. Synergistic effects were observed between these variables, suggesting that these variables conditioned insect distribution and reproduction, and not just temperature per se.

scholarly journals Spatial and temporal variation in densities of chironomid larvae (Diptera) in two lagoons and two tributaries of the upper Paraná River floodplain, Brazil

2002 ◽  
Vol 62 (4b) ◽  
pp. 807-818 ◽  
Author(s):  
J. HIGUTI ◽  
A. M. TAKEDA
Keyword(s):  
Temporal Variation ◽  
Temporal Dynamics ◽  
Paraná River ◽  
Spatial And Temporal Variation ◽  
Chironomid Larvae ◽  
River Floodplain ◽  
Parana River ◽  
Upper Paraná River Floodplain ◽  
Upper Paraná River ◽  
Paraná River Floodplain

Chironomid larvae were collected and abiotic variables measured at monthly intervals at 21 sampling stations in two lagoons (Guaraná and Patos) and two tributaries (Baía and Ivinheima) of the Upper Paraná River floodplain. The genera Procladius, Chironomus, Goeldichironomus, and Polypedilum were dominant in the lagoons and in the Baía River, while Cryptochironomus and Lopescladius were more dominant in the Ivinheima River. The similarity in the generic composition of the chironomids of the lagoons and the Baía River is probably due to the fact that this river presents hydrodynamic characteristics similar to those of the lagoons. The results obtained suggest that the hydrodynamics of these environments are the main factor determining spatial variation in the chironomid fauna. This is intuitively clear, as this factor itself determines sediment type, quantity of organic matter and presence or absence of aquatic macrophytes. However, on a seasonal scale, the flood pulse seems to be the main controlling factor of the temporal variation in densities and dominance of chironomid larvae. Given that this factor has a large influence on the temporal dynamics of several limnological variables, this is again a logical correlation. Our results suggest a strong relationship between the variations in the chironomid community and fluctuations in limnological characteristics.

Improving reliability in environmental DNA detection surveys through enhanced quality control

2017 ◽  
Vol 68 (2) ◽  
pp. 388 ◽  
Author(s):  
Elise M. Furlan ◽  
Dianne Gleeson
Keyword(s):  
Quality Control ◽  
Native Species ◽  
Conservation Management ◽  
Environmental Dna ◽  
Positive Control ◽  
False Negatives ◽  
Method Error ◽  
Target Dna ◽  
Species Specific ◽  
Australian Freshwater

Species-specific environmental DNA (eDNA) surveys are increasingly being used to infer species presence in an environment. Current inadequacies in quality control increase concern for false negatives, which can have serious ramifications for both the management of invasive species and the conservation of native species. eDNA surveys involve a multi-step process to sample, capture, extract and amplify target DNA from the environment. We outline various positive control options and show that many of the commonly used controls are capable of detecting false negatives arising during the amplification stage only. We suggest a secondary, generic primer, designed to co-amplify endogenous DNA sampled during species-specific eDNA surveys, constitutes a superior positive control to monitor method success throughout all stages of eDNA analysis. We develop a species-specific European carp (Cyprinus carpio) assay and a generic fish assay for use as an endogenous control for eDNA surveys in Australian freshwater systems where fish are known to be abundant. We use these assays in a multiplex on eDNA samples that are simultaneously sampled, captured, extracted and amplified. This positive control allows us to distinguish method error from informative non-amplification results, improving reliability in eDNA surveys, which will ultimately lead to better informed conservation management decisions.

scholarly journals Hot spot detection and spatio-temporal dynamics of dengue in Queensland, Australia

2014 ◽  
Vol XL-8 ◽  
pp. 197-204 ◽  
Author(s):  
S. Naish ◽  
S. Tong
Keyword(s):  
Temporal Variation ◽  
Temporal Dynamics ◽  
Hot Spot ◽  
Seasonal Pattern ◽  
Temporal Distribution ◽  
Health Concern ◽  
Spatial And Temporal Variation ◽  
Dengue Case ◽  
Spatio Temporal ◽  
Over Time

Dengue has been a major public health concern in Australia since it re-emerged in Queensland in 1992–1993. This study explored spatio-temporal distribution and clustering of locally-acquired dengue cases in Queensland State, Australia and identified target areas for effective interventions. A computerised locally-acquired dengue case dataset was collected from Queensland Health for Queensland from 1993 to 2012. Descriptive spatial and temporal analyses were conducted using geographic information system tools and geostatistical techniques. Dengue hot spots were detected using SatScan method. Descriptive spatial analysis showed that a total of 2,398 locally-acquired dengue cases were recorded in central and northern regions of tropical Queensland. A seasonal pattern was observed with most of the cases occurring in autumn. Spatial and temporal variation of dengue cases was observed in the geographic areas affected by dengue over time. Tropical areas are potential high-risk areas for mosquito-borne diseases such as dengue. This study demonstrated that the locally-acquired dengue cases have exhibited a spatial and temporal variation over the past twenty years in tropical Queensland, Australia. There is a clear evidence for the existence of statistically significant clusters of dengue and these clusters varied over time. These findings enabled us to detect and target dengue clusters suggesting that the use of geospatial information can assist the health authority in planning dengue control activities and it would allow for better design and implementation of dengue management programs.

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