Types Of Water Bodies Research Articles

Do bats seek clean water? A perspective on biodiversity from the Namib Desert

Water abundance, distribution, and quality are key elements affecting species distributions in arid environments, yet how their interactions structure specific animal communities is often unclear. To address this knowledge gap, we examined relationships between bodies of water and bat communities in the northern Namib Desert. We predicted that water quality would be poorer (i.e., higher indices of electrical conductivity and ion concentrations) during the dry season and at artificial pools, and that bat species richness and activity would consequently be lower at these sites. We conducted extensive fieldwork at the terminus of the hot, dry season from November 2016 to January 2017 and at the conclusion of the following wet season from March to May 2017, collecting water samples and acoustic recordings of bat activity at both natural springs (n = 18) and artificial pools (n = 5). Overall activity (but not species richness) was greater during the wet season and at artificial pools, but we did not find systematic differences in water quality driven by seasonality or water body type. Although individual artificial pools harbored significantly greater bat activity, >35% of the species that we recorded were present only at natural springs. While bat species richness was reduced at saline sites, only the activity of the Zulu serotine also related to water quality. In general, water surface area was more often associated with bat activity in the Namib Desert than was water quality.

Potential of restored gravel pits to provide suitable habitats for Eurasian otters in anthropogenic landscapes

In anthropogenic landscapes, which are usually characterized by the existence of highly heterogeneous patchworks of habitats with different conservation status, restored gravel pits have the potential to play a conservation role for semiaquatic species such as Eurasian otters (Lutra lutra). Here, we report an otter habitat suitability analysis on a complex fluvial system in an anthropogenic landscape to understand the role of different artificial water bodies (i.e. irrigation channels and ditches) and natural water bodies (i.e. rivers) related to a restored gravel pit lagoon system as providers of suitable habitats for otters. We implemented seven sampling campaigns during 2016 and 2017 consisting of 19 transects across all existing types of water bodies. We integrated 34 environmental variables with otter habitat use, measured by three spraint marking intensity indicators. We found that otter use of water bodies was not related to the natural or artificial origin of the water. Three key factors influenced habitat suitability: riparian vegetation tree cover, forestland use (either natural or planted) within 100 m from the banks, and the level of human disturbance. Our results suggest that otters' tolerance of human activities might be lower in key areas of their territory compared to areas they pass through or explore. We argue that restored gravel pit lagoon systems can potentially play a role in providing suitable habitats for otters in anthropogenic landscapes.

Comparing key drivers of cyanobacteria biomass in temperate and tropical systems

There is growing evidence that cyanobacterial blooms are becoming more common in different parts of the world; within this context, predictive cyanobacteria models have an essential role in lake management. Several models have been successfully used in temperate systems to describe the main drivers of cyanobacterial blooms, but relatively less work has been conducted in the Tropics. We analyzed data from six Brazilian reservoirs and from five Canadian lakes using a combination of regression tree analyses and variation partitioning to evaluate the similarities and differences between regions. Our results, together with a synthesis of the literature from different latitudes, showed that trophic state (i.e. nutrients), climatic variables (e.g., temperature and/or precipitation) and hydrodynamic regimes (i.e. water residence time) are significant drivers of cyanobacteria biomass over several scales. Nutrients came out as the primary predictor in both regions, followed by climate, but when all systems were pooled together, water residence time came out as most important. The consistency in variables identified between regions suggests that these drivers are widely important and cyanobacteria responded quite similarly in different geographical settings and waterbody types (i.e. lakes or reservoirs). However, more work is needed to identify key thresholds across latitudinal gradients. Taken together, these results suggest that multi-region syntheses can help identify drivers that predict broad-scale patterns of cyanobacteria biomass.

Identification and characterization of immature Anopheles and culicines (Diptera: Culicidae) at three sites of varying malaria transmission intensities in Uganda

BackgroundOver the last two decades, there has been remarkable progress in malaria control in sub-Saharan Africa, due mainly to the massive deployment of long-lasting insecticidal nets and indoor residual spraying. Despite these gains, it is clear that in many situations, additional interventions are needed to further reduce malaria transmission. The World Health Organization (WHO) has promoted the Integrated Vector Management (IVM) approach through its Global Vector Control Response 2017–2030. However, prior roll-out of larval source management (LSM) as part of IVM, knowledge on ecology of larval aquatic habitats is required.MethodsAquatic habitats colonized by immature Anopheles and culicines vectors were characterized at three sites of low, medium and high malaria transmission in Uganda from October 2011 to June 2015. Larval surveys were conducted along transects in each site and aquatic habitats described according to type and size. Immature Anopheles, culicines and pupae from the described habitats were sampled using standard dipping methods to determine larval and pupae densities. Larvae were identified as anopheline or culicine, and counted. Pupae were not identified further. Binary logistic regression analysis was used to identify factors associated with the presence of immature Anopheles and culicines in each site.ResultsA total of 1205 larval aquatic habitats were surveyed and yielded a total of 17,028 anopheline larvae, 26,958 culicine larvae and 1189 pupae. Peaks in larval abundance occurred in all sites in March–May and August-October coinciding with the rainy seasons. Anopheles larvae were found in 52.4% (n = 251) of aquatic habitats in Tororo, a site of high transmission, 41.9% (n = 536) of habitats in Kanungu, a site with moderate malaria transmission, and 15.8% (n = 418) in Jinja, a site with low malaria transmission. The odds of finding larvae was highest in rice fields compared to pools in both Tororo (odds ratio, OR = 4.21, 95% CI 1.22–14.56, p = 0.02) and Kanungu (OR = 2.14, 95% CI 1.12–4.07, p = 0.02), while in Jinja the odd were highest in containers (OR = 4.55, 95% CI = 1.09–19.14, p = 0.03). In Kanungu, larvae were less likely to be found in containers compared to pools (OR = 0.26, 95% CI 0.09–0.66, p = 0.008) and river fringe (OR = 0.19, 95% CI 0.07–0.52, p = 0.001). Medium sized habitats were associated with high odds of finding larvae compared to small habitats (OR = 3.59, 95% CI 1.18–14.19, p = 0.039).ConclusionsThese findings show that immature Anopheles and culicines were common in areas of high and moderate transmission but were rare in areas of low transmission. Although immature Anopheles and culicines were found in all types of water bodies, they were most common in rice fields and less common in open drains and in river fringes. Methods are needed to reduce the aquatic stages of anopheline mosquitoes in human-made habitats, particularly rice fields.

Riparian Ground Beetles (Coleoptera) on the Banks of Running and Standing Waters

Rivers and their floodplains offer a wide variety of habitats for invertebrates. River ecosystems are subject to high anthropic influence: as a result the channel morphology is changed, swamps are drained, floodplains are built up, and rivers are polluted. All this has radically changed the environment for the inhabitants of the floodplains, including riparian stenotopic species. Although riparian arthropods are oriented primarily to the production of hydro-ecosystems, the type of water body—lentic or lotic—has a determining effect in the structure of communities. Most riparian arthropods have evolutionarily adapted to riverbanks with significant areas of open alluvial banks. This paper considered the structure of assemblages of ground beetles associated with the riverbanks and the shores of floodplain lakes and their differences. The banks of rivers and the shores of floodplain lakes were considered separately due to the differences in the habitats associated with them. Our results showed that riverbanks, which experience significant pollution, were actively colonized by vegetation and were unsuitable for most riparian ground beetles. The shores of floodplain lakes, being an optional habitat for riparian arthropods, cannot serve as refugia. Thus, the transformation of floodplain landscapes and river pollution creates a problem for the biological diversity of floodplain ecosystems, since riparian stenotopic species of the riverbanks become rare and disappear.

Morphological and biological Features of Parthenogenetic and Dioecious generations Schistosoma turkestanicum skrjabin, 1913

The purpose of the research is to study of the morphological and biological characteristics of parthenogenetic and dioecious generations of the trematode Schistosoma turkestaniсum – a parasite of mammals of Uzbekistan.Materials and methods. Populations of mature trematodes from animals and mollusks Lymnaea auricularia from different types of water bodies of Uzbekistan were collected and studied. Experimentally reproduced the development of trematodes in the body of the intermediate and definitive hosts according to generally accepted methods.Results and discussion.The morphological and biological features of all phases of the development of Sch. turkestanicum under experimental conditions. Some new data on the morphology of the parasite having taxonomic meanings and the distribution of Sch. turkestanicum in Uzbekistan.

Effects of landscape heterogeneity and breeding habitat diversity on rice frog abundance and body condition in agricultural landscapes of Yangtze River Delta, China.

Amphibians play a key role in structuring biological assemblages of agricultural landscapes, but they are threatened by global agricultural intensification. Landscape structure is an important variable influencing biodiversity in agricultural landscapes. However, in the Yangtze River Delta, where a "farmland-orchard-fishpond" agricultural pattern is common, the effects of landscape construction on anuran populations are unclear. In this study, we examined the effects of agricultural landscape parameters on the abundance and body condition of the rice frog (Fejervarya multistriata), which is a dominant anuran species in farmland in China. Employing a visual encounter method, we surveyed rice frog abundance for 3 years across 20 agricultural landscapes. We also calculated the body condition index (BCI) of 188 male frog individuals from these agricultural landscapes. Landscape variables, comprising landscape compositional heterogeneity (using the Shannon diversity index of all land cover types except buildings and roads), landscape configurational heterogeneity (using landscape edge density), breeding habitat diversity (using the number of 5 waterbody types available as breeding habitats), and areas of forest were also measured for each 1-km radius landscape. We found that the amount of forest in each agricultural landscape had a significant positive relationship with rice frog abundance, and breeding habitat diversity was positively related to the BCI of male rice frogs. However, body condition was negatively impacted by landscape configurational heterogeneity. Our results suggested the importance of nonagricultural habitats in agricultural landscapes, such as waterbodies and forest, to benefit rice frog population persistence.

Acoustic and morphological variation on two populations of Dryophytes arenicolor in central México

ABSTRACT Contrasting conditions of different habitats lead to geographic variation among populations of the same species. In widespread species, trait divergence represents a response to spatial variation in local habitat conditions and biotic interactions. Morphology and call characteristics are crucial for anuran fitness because of their direct impacts on survival and reproduction. Our aim was to analyse and compare morphological and call characteristics of two populations of Dryophytes arenicolor in central Mexico where waterbody types and presence of other species (D. eximius) differed. We measured morphological characteristics, estimated the sex ratio, and characterised the advertisement calls for each population. We found that the sex ratio differed among populations: in one population, the sex ratio was male-biased. No morphological variation was detected between populations; however, females had longer limbs and higher mass. We found differences in call characteristics among populations and even among individuals of the same population. There was an effect of calling context (solitary or chorus) on call characteristics, we found that calls from conspecifics led to an increase in values of spectral characteristics and reduction of temporal ones, whereas calls from D. eximius resulted in a decrease in values of spectral characteristics and increase in temporal ones.

High-resolution monitoring of inland water bodies across China in long time series and water resource changes

The accurate examination of inland water body distributions, types, areas and sizes is critical for global water cycling, while water resources and the diagnosis of utilization problem are essential to sustainable water management. Therefore, there remain less well-studied in China, especially for the accurate examination of long time series. Based on high-resolution satellite imagery from the late 1970s, statistical water resource data and precipitation data, this study identifies inland rivers, lakes, reservoirs and ponds larger than 0.001 km2, examines the regularity of different water distributions; analyzes area, perimeter and water resource changes for ten basins from long time series, quantitatively and qualitatively analyzes determinants, and illustrates main characteristics and water use problems affecting each basin and presents a number of suggestions. The results show that inland water body areas increased from 1980 to 2015 and that reservoir and pond areas increased considerably, while lake and river areas changed little. Land surface water resources and precipitation declined slightly from 1997 to 2015. Climatic conditions determine basic water body and resource distributions and volumes at the macroscopic scale, and human activities have greatly altered spatial patterns. Basin with rivers in the southwest includes highly exploitable water resources. Basin with rivers in the northwest faces considerable water shortages and fragile environmental conditions. The Yellow River, the Haihe River and the Songhua and Liaohe River Basins suffer from water shortages and pollution. The other four basins are experiencing eutrophication and frequent meteorological and geological hazards. Sustainable water management must be based on basin characteristics and major problems.

Tadpoles in the diet of otters – an overlooked prey item in the diet of a riparian predator?

Understanding the diets of predators, prey selection and their impact on prey populations is pivotal to investigations on the ecology of predator and prey species. In this study, we observed a hand-reared European otter (Lutra lutra) foraging in the wild, in order to identify the type of prey captured by the predator. The study was carried out between March and June 2001 in a diverse range of natural otter habitats in Białowieża Forest (NE Poland). We found that tadpoles represented an important part of the otter's diet in June, when their frequency of occurrence and biomass reached 38% and 11%, respectively. During spring, tadpoles were less common than other types of prey, such as adult amphibians, fish, or aquatic Coleoptera. Otter diet varied among months and there were differences in the main prey type captured among water body types. Our results highlight the need to develop methods that enable the identification of tadpoles and other cryptic seasonal food items in riparian predator diets.

Towards the Development of an Affordable and Practical Light Attenuation Turbidity Sensor for Remote Near Real-Time Aquatic Monitoring.

Turbidity is a key environmental parameter that is used in the determination of water quality. The turbidity of a water body gives an indication of how much suspended sediment is present, which directly impacts the clarity of the water (i.e., whether it is cloudy or clear). Various commercial nephelometric and optical approaches and products exist for electronically measuring turbidity. However, most of these approaches are unsuitable or not viable for collecting data remotely. This paper investigates ways for incorporating a turbidity sensor into an existing remote aquatic environmental monitoring platform that delivers data in near real-time (i.e., 15-min intervals). First, we examine whether an off-the-shelf turbidity sensor can be modified to provide remote and accurate turbidity measurements. Next, we present an inexpensive design for a practical light attenuation turbidity sensor. We outline the sensor’s design rationale and how various technical and physical constraints were overcome. The turbidity sensor is calibrated against a commercial turbidimeter using a Formazin standard. Results indicate that the sensor readings are indicative of actual changes in turbidity, and a calibration curve for the sensor could be attained. The turbidity sensor was trialled in different types of water bodies over nine months to determine the system’s robustness and responsiveness to the environment.

Nature based measures increase freshwater biodiversity in agricultural catchments

This is the first study that describes the effect of adding mitigation measures on the freshwater biodiversity of all waterbody types in agricultural catchments. We measured alpha (site) and gamma (catchment) richness annually over a nine-year period in all the streams, ponds and ditches in three upper-catchments in the English lowlands, and investigated whether freshwater plant biodiversity could be increased by adding: (i) multi-functional ecosystem services measures to intercept pollutants, store water and promote biodiversity, and, (ii) biodiversity-only protection measures. In the absence of measures, all catchments saw a decline in macrophyte richness during the survey (mean species loss of 1% pa, rare species loss of 2% pa). Ponds were a key habitat with a disproportionate influence on catchment trends. Five years after introducing measures, natural colonisation of ecosystem services waterbodies (dammed streams and ditches, runoff ponds, flood storage ponds) largely cancelled-out the background loss of plant species but, importantly, did not restore the loss of rare plants. Adding clean water ponds as a biodiversity-only enhancement measure brought substantial benefits: increasing total-catchment richness by 26%, and the number of rare plant species by 181%. Populations of spatially restricted species also increased. Adding stream debris-dams as a biodiversity measure did not affect plant richness or rarity. The findings suggest that ecosystem services measures could bring some biodiversity benefits to agricultural catchments. However, creating clean-water ponds specifically targeted for biodiversity could hold considerable potential as a tool to help stem, and even reverse, ongoing declines in freshwater plant biodiversity across farming landscapes.

A Multi-Scale Water Extraction Convolutional Neural Network (MWEN) Method for GaoFen-1 Remote Sensing Images

Automatic water body extraction method is important for monitoring floods, droughts, and water resources. In this study, a new semantic segmentation convolutional neural network named the multi-scale water extraction convolutional neural network (MWEN) is proposed to automatically extract water bodies from GaoFen-1 (GF-1) remote sensing images. Three convolutional neural networks for semantic segmentation (fully convolutional network (FCN), Unet, and Deeplab V3+) are employed to compare with the water bodies extraction performance of MWEN. Visual comparison and five evaluation metrics are used to evaluate the performance of these convolutional neural networks (CNNs). The results show the following. (1) The results of water body extraction in multiple scenes using the MWEN are better than those of the other comparison methods based on the indicators. (2) The MWEN method has the capability to accurately extract various types of water bodies, such as urban water bodies, open ponds, and plateau lakes. (3) By fusing features extracted at different scales, the MWEN has the capability to extract water bodies with different sizes and suppress noise, such as building shadows and highways. Therefore, MWEN is a robust water extraction algorithm for GaoFen-1 satellite images and has the potential to conduct water body mapping with multisource high-resolution satellite remote sensing data.

Planktonic algae abundance and diversity are similar in urban stormwater ponds of different geographic locations and natural shallow lakes

Elevated levels of different contaminants are typical to stormwater management ponds. Despite that, a number of works report stormwater ponds serving as habitats for a variety of biota. In this study we aimed to examine phytoplankton communities of urban ponds, as the basis of the aquatic food web, and compare them to those of natural shallow lakes. Stormwater ponds were selected from two distant geographic locations: three in Denmark and three in Canada. As a reference to natural systems, three Danish shallow lakes were sampled. The sampling was carried out in the spring, summer and fall of 2014. The phytoplankton communities in ponds were found to be at least as rich in taxa as natural shallow lakes. Their abundance and biovolume varied highly among the types of water bodies as well as in each pond or lake individually, depending on the sampling month. We did not find any significant differences among ponds and natural shallow lakes at the investigated taxonomic level, despite some distinction observed by multivariate DCA and CCA analyses. Little difference was found between Canadian and Danish ponds as well, even though they are separated by a large geographic distance. This study shows that stormwater ponds are habitats for diverse planktonic algae communities which have some similarities to those of natural shallow lakes. Also, the similarities observed between Danish and Canadian ponds indicate some consistence with the urban homogenization hypothesis, although this should be further looked into by future works examining a larger number and distinct types of ponds.

Connectivity of Neotropical River Basins in the Central Guiana Shield Based on Fish Distributions

The Guiana Shield in northeastern South America contains some of the largest tracts of intact forests on the globe. Guyana alone has more than 80% forest cover. In south-central Guyana a unique biogeographic feature allows for a hydrological connection between the Guiana Shield with the Amazon basin via the Rupununi savannas and wetlands (Rupununi Portal). This corridor allows for connectivity between two of the most biodiverse, carbon rich and intact forests in the world. The significance of this (and other) hydrological corridors for terrestrial and aquatic species are underappreciated in the scientific literature. We attempt to determine the importance of the surrounding mosaic of habitats that influence fish assemblages in the Rupununi Portal. We extensively sampled fishes in this corridor over six expeditions. Multivariate analyses revealed significant trends in fish assemblage structure and environmental conditions. We found high species richness and diversity within the Takutu (Amazon River drainage) and Rupununi rivers (Essequibo River drainage). Fish assemblages were found to be most similar within the specific river drainages with some similarity within forest and savanna sites. A second Rupununi portal was revealed in the South Rupununi, at the upper Rupununi and Takutu Rivers. Ordination analyses found water body type, vegetation and water chemistry to be significantly structuring the fish assemblages of the Rupununi. Our study reveals the interdependent nature of the various habitats in the Rupununi that facilitate high biodiversity and maintain the ecosystem. With the increase in human activity in this region, and the increased connectivity of the region with the rest of the world through better roads, this area is in danger of being modified and fragmented to a point where ecosystem services begin to fail. We recommend demarcating a protected area in the region that considers the diversity of associated habitats and the importance of the ecological portal joining two diverse river basins.

Magnetotactic bacteria diversity of and magnetism contribution to sediment in Wudalianchi volcanic barrier lakes, NE China

Magnetotactic bacteria (MTB), the members of sediment microorganisms, play an important role in geochemical iron-cycling and sediment magnetism. This study aimed to investigate the diversity and magnetism contribution of MTB in three volcanic barrier lakes with different waterbody types (open waterbody, YC; semi-enclosed waterbody, WB; and enclosed waterbody, YYP). High-throughput sequencing results showed that MTB affiliated to Alphaproteobacteria, Betaproteobacteria and Nitrospira distributed widely in these lakes. The genera of Magnetococcus (98.10%) and Candidatus Magnetoovum (1.47%) were endemic to YC and WB, respectively. The changes in frequency-dependent susceptibility (χfd) values before and after magnetic collection in YC, WB and YYP samples were − 0.28%, 0.05% and − 0.22%, respectively. The magnetic susceptibility was significantly associated with Chao1 (R2 = 0.637 to 0.763, p < .01) and Shannon index (R2 = 0.803 to 0.998, p < .01). The room- and low-temperature magnetic characteristics of sediment samples were analyzed by vibrating sample magnetometer (VSM) and radio-frequency superconducting quantum interference device (SQUID). Results indicated that the presence or absence of MTB could lead to the changes in the room- and low-temperature magnetism of volcanic lake sediments, which would extend our knowledge of MTB magnetism contribution to volcanic ecosystems.

SXT int harboring bacteria as effective indicators to determine high-risk reservoirs of multiple antibiotic resistance in different aquatic environments of western coast of Gujarat, India

Unregulated use of antibiotics in the developing countries has led to the development of Multiple Antibiotic Resistant (MAR) strains. Resistance transferring elements like SXT play crucial role in dissemination of the resistance genes. Persistence of antibiotics and their resistance elements in an aquatic ecosystem depends on the physicochemical properties, and thus may depend on the type of whole water body in general. The study focuses on isolation of bacteria possessing SXT integrase from diverse aquatic bodies like polluted sources, freshwater ponds, groundwater and seawaters of western Gujarat coast, and studying distribution of multidrug resistance in them. Initially, 246 Co-Trimoxazole resistant microbes were isolated from various environmental samples on the basis of morphological distinction. In the PCR analysis, 45 of them were found to be positive for the SXT integrase gene and subsequent analysis confirmed the presence of SXT or SXT-variants. Partial 16S rRNA gene sequencing and diversity analysis on the basis of Shannon’s diversity indices revealed bacterial class-wise diversity trend to be pond water > seawaters > ground water > polluted sources. Antibiogram of these organisms revealed the order of antibiotic resistance indices to be polluted sources > groundwater sources > freshwater ponds > seawater sources. However, the trend of percentage resistance towards antibiotic classes separately in the studied aquatic environments was groundwater sources > polluted sources > freshwater ponds > seawater. Further, the trend for therapeutic efficiency of antibiotic classes was similar in all waters to that of total isolates i.e. Aminoglycosides > Fluoroquinolones > Amphenicols > Cephalosporins > Imidazolidinedione derivatives > Glycopeptide > Quinolones > Macrolides > Penicillins > Sulfa drugs. Positive correlation was observed between prevalence of SXT int positive bacteria and multiple antibiotic resistance incidences; but negative correlation was observed between SXT int positive bacteria and class wise bacterial diversity in four designated type of aquatic environment. Thus, screening for occurrence frequency of SXT integrase gene in the bacterial isolates, may prove as an effective parameter to estimate the multiple antibiotics’ resistance indices in any of the four studies aquatic ecosystems, and thereby determine the antibiotic pollution resulting in the corresponding pressure. The overall quantitative values were logically higher in polluted sources in terms of total resistance indices, and freshwater ponds in terms of diversity. But the groundwater sites may be regarded as the prominent high-risk zones of contamination with multiple antibiotic and/or their resistance traits qualitatively.

Comparison of planktonic and reed biofilm bacteria in different riverine water bodies of river Danube

AbstractAs the submerged shoot parts of common reed (Phragmites australis) can provide large surfaces for biofilm‐forming bacteria, extensive reed stands can effectively contribute to the self‐purification in the littoral zones of freshwaters. However, bacterial biofilm developed on reed surfaces have been studied only in still waters. In the present study, comparative examinations were performed on the planktonic and reed biofilm bacterial communities from two different riverine water bodies. Water and reed biofilm samples were taken at the beginning and end of the vegetation period from (a) a regulated side arm and (b) a separated oxbow of River Danube. Besides measuring physical and chemical environmental variables, planktonic bacterial cell numbers were detected by 4′,6‐diamidino‐2‐phenylindole staining method, and the bacterial communities were compared by denaturing gradient gel electrophoresis. Our results demonstrated that the structure and composition of bacterial communities correlated with different environmental variables and were different regarding both the habitats (planktonic vs. reed biofilm) and the types of riverine water bodies. The seasonal differences in the bacterial community structures were smaller in the river side arm than in the separated oxbow. In the water column, representatives of widespread and typical freshwater planktonic bacteria (“Candidatus Planktophila,” Limnohabitans, and Polynucleobacter), whereas, in the reed biofilm samples, phototrophic and plant associated bacteria were identified.

Integrating various satellite images for identification of the water bodies through using machine learning: A case study of Salah Adin, Iraq

This research aims to extract water bodies from several types of satellite images by using machine learning. There are several methods to apply the extraction of information about water bodies such as unsupervised classification, supervised classification. This project applied the supervised classification method to extract water bodies and building geodatabase for the water bodies in Salah Adin, Iraq by applying remote sensing and GIS technique. The satellite images which have been used in this research include satellite images from RapideEye satellite with spatial resolution (5×5) m at 2011, where these images used to extract canals of water, also used images from Sentinel-2 satellite with spatial resolution (10 × 10) m at 2017 to extract lakes, and broad rivers. In addition, DEM raster (90) m at 2011 from ASTER satellite was used to extract the water streams, which are expected to be channels of water discharge in flood situations. During implementation of the methodology of the research the most important issue which appear is using multi data to extract all types of water bodies in study area also to avoid the pixel mixed problem, this case was evident when using RapidEye satellite images in the confluence of the river in the surrounding wetlands, which led to inaccurate results in the geometric dimensions of the river, although the high spatial resolution but the influenced element on the accuracy of results is radiometric resolution. The result shows the random forest of machine learning algorithm is overcome on the other algorithms such as decision tree machine learning, maximum likelihood and support vector machine. The high accuracy of image classification to extract the water bodies depend on integrating the three satellite images.

Ecosystem-specific growth responses to climate pattern by a temperate freshwater fish

Abstract Somatic growth patterns among animal populations are maintained through complex processes that vary among ecosystems. Changes in growth patterns may be concomitant with changes in climate; however, understanding how growth will manifest among ecosystems is limited. Information embedded within fish hard-parts (i.e., otoliths, spines, vertebrae) can account for variation in growth patterns resulting from changing climate conditions. Channel catfish Ictalurus punctatus is a freshwater fish species widely distributed across North America with limited information regarding climate influences on growth and differences in climate-growth relations among ecological systems. We assessed growth (total length) response to changing climate conditions for channel catfish among three waterbody types—pit lakes, irrigation and power-generation reservoirs, and flood-control reservoirs in Nebraska, USA. We used linear mixed-effect models and an information theoretic approach to assess the relative strengths among competing hypotheses. The most supported linear mixed-effect model of channel catfish growth was a function of fish age and an interaction between waterbody type and growing-degree-day (GDD). A positive trend existed in GDD from 1990 through 2008 whereby the predicted increase in GDD among waterbody types ranged from 182 GDD to 189 GDD. The predicted change in channel catfish growth resulting from increased GDD ranged from 1% to 39% among waterbody types. Channel catfish population rate functions, thus, may not respond similarly to climate conditions across ecosystem types. Changes in climate variables may contribute to system-specific responses in population dynamics for channel catfish as well as other similar freshwater species. The establishment of relations between climate and growth variables for a freshwater generalist with a plastic diet and broad temperature tolerance serves as an indication of the breadth of responses possible for freshwater fishes under global changes in climate conditions.