Freshwater Research Papers - Academia.edu (original) (raw)

Food habits of co-occurring largemouth bass (Micropterus salmoides) and spotted bass (M. punctulatus) were documented in two New Mexico reservoirs, Brantley Lake and Sumner Lake, from May 2001 to May 2002. In Brantley Lake, bass ate... more

Food habits of co-occurring largemouth bass (Micropterus salmoides) and spotted bass (M. punctulatus) were documented in two New Mexico reservoirs, Brantley Lake and Sumner Lake, from May 2001 to May 2002. In Brantley Lake, bass ate mainly fish, whereas bass in Sumner Lake ate mainly crayfish. Food habits of both species varied seasonally and there was substantial overlap in the

Within the context of global climate changes, it is expected that low-lying coastal freshwater ecosystems will face seawater intrusion with concomitant increase in salinity levels. Increased salinity may provoke disruption of competitive... more

Within the context of global climate changes, it is expected that low-lying coastal freshwater ecosystems will face seawater intrusion with concomitant increase in salinity levels. Increased salinity may provoke disruption of competitive relationships among freshwater species. However, species may be capable of acclimating to salinity, which, in turn, may influence the resilience of ecosystems. Accordingly, this work aimed at assessing the effects of multigenerational exposure to low levels of salinity in the competitive outcome of two species of green microalgae: Raphidocelis subcapitata and Chlorella vulgaris. To attain this, three specific objectives were delineated: (1) compare the toxicity of natural seawater (SW) and NaCl (as a surrogate of SW) to the two microalgae, (2) determine the capacity of the two microalgae species to acclimate to low salinity levels, and (3) assess the influence of exposure to low salinity levels in the competitive outcome of the two microalgae. Results revealed SW to be slightly less toxic than NaCl for the two microalgae. The EC 25,72 h for growth rate was 4.63 and 10.3 mS cm −1 for R. subcapitata and 6.94 and 15.4 mS cm −1 for C. vulgaris, respectively for NaCl and SW. Both algae were capable of acclimating to low levels of salinity, but C. vulgaris seemed to acclimate faster than R. subcapitata. When exposed in competition, under control conditions, the growth rates of C. vulgaris were lower than those of R. subcapitata. However, C. vulgaris was capable of acquiring competitive advantage equaling or surpassing the growth rate of R. subcapitata with the addition of NaCl or SW, respectively. The multigenerational exposure to low levels of salinity influenced the competitive outcome of the two algae both under control and salinity exposure. These results suggest that long-term exposure to low salinity stress can cause shifts in structure of algae communities and, therefore , should not be neglected since algae are at the basis of food web constituting important energetic resources to higher trophic levels.

Seven family-level metrics were determined from benthic macro invertebrate samples collected monthly across four different landuse sites in the Cazenovia Creek watershed in western New York. We evaluated which metrics were most... more

Seven family-level metrics were determined from benthic macro invertebrate samples collected monthly across four different landuse sites in the Cazenovia Creek watershed in western New York. We evaluated which metrics were most appropriate for, and effective in. discerning differences among the sites. Dramatic and consistent seasonal differences in metric scores were observed across all sites. All metric scores indicated markedly better biological health during winter months than during summer months. The biological impairment designation was highest in the summer at the suburban and agricultural sites. Coefficients of variation were considerably greater at the lower stream order sites. The metrics that vvere most appropriate and effective in assessing benthic assemblage health in this study were: richness, percent model affinity, family-level biotic index. and Ephemeroptera-Plecoptera-Trichoptera index. These indices correlated with a low amount of redundancy in a Pearson matrix, had significant discriminatory power in assessing biological impairments across sites, and had low variation within sites and seasons. This suggests these metrics should be selected for bioassessments in similar Great Lakes watersheds.

1. The variable ecological response of lakes to reduced nutrient loading (oligotrophication) at sites in Europe and North America was discussed at a workshop held in Silkeborg (Denmark) in January 2003. Studies of lake oligotrophication... more

1. The variable ecological response of lakes to reduced nutrient loading (oligotrophication) at sites in Europe and North America was discussed at a workshop held in Silkeborg (Denmark) in January 2003. Studies of lake oligotrophication were presented based on both long-term monitoring and data generated by palaeolimnological methods. 2. This introduction to the special issue provides short summaries of a series of the papers presented and their limnological context. Results show that the majority of lakes had approached a new equilibrium of phosphorus (P) and nitrogen (N) concentrations 10-15 years (P) and 0-5 years (N) after a major reduction in loading, irrespective of hydraulic retention time. Phytoplankton biomass decreased and a shift towards meso-oligotrophic species dominance occurred. The fish responded surprisingly fast to the loading reduction in most lakes. As a result, the percentage of piscivores increased and total fish biomass declined markedly, which may explain an increase in the body size of cladocerans and an increase in the zooplankton to phytoplankton biomass ratio seen in many of the lakes. 3. Monitoring has in general been initiated after the effects of eutrophication became apparent. In this context palaeolimnological techniques become very useful because they allow limnologists to extend time scales of coverage and to define restoration targets and baseline conditions. Moreover, lake sediments pre-dating anthropogenic disturbance can be used to examine ecological response to, for instance, climate variability, allowing problems associated with multiple stressors to be addressed. 4. It is concluded that there is a great need for a synthetic, holistic approach to studying lake oligotrophication, combining multiple techniques of palaeolimnological sediment analysis with detailed but temporally limited long-term monitoring of chemical and biological variables. This is important, not least to assess future responses to nutrient loading reductions, as global warming will interact with a range of external stressors and ultimately affect lake management strategies to deal with the resultant feedbacks.

1. The in¯uence of 11 environmental variables on benthic macroinvertebrate communities was examined in seven glacier-fed European streams ranging from Svalbard in the north to the Pyrenees in the south. Between 4 and 11 near-pristine... more

1. The in¯uence of 11 environmental variables on benthic macroinvertebrate communities was examined in seven glacier-fed European streams ranging from Svalbard in the north to the Pyrenees in the south. Between 4 and 11 near-pristine reaches were studied on each stream in 1996±97. 2. Taxonomic richness, measured at the family or subfamily (for Chironomidae) levels for insects and higher levels for non-insects, increased with latitude from Svalbard (3 taxa) to the Pyrenees (29 taxa). 3. A Generalized Additive Model (GAM) incorporating channel stability [Pfankuch Index (PFAN)], tractive force, Froude number (FROU), water conductivity (COND), suspended solids (SUSP) concentration, and maximum temperature explained 79% of the total deviance of the taxonomic richness per reach. Water temperature and the PFAN of stability made the highest contribution to this deviance. In the model, richness response to temperature was positive linear, whereas the response to the PFAN was bell-shaped with an optimum at an intermediate level of stability. 4. Generalized Additive Models calculated for the 16 most frequent taxa explained between 25 (Tipulidae) and 79% (Heptageniidae) of the deviance. In 10 models, more than 50% of the deviance was explained and 11 models had cross-validation correlation ratios above 0.5. Maximum temperature, the PFAN, SUSP and tractive force (TRAC) were the most frequently incorporated explanatory variables. Season and substrate characteristics were very rarely incorporated. 5. Our results highlight the strong deterministic nature of zoobenthic communities in glacier-fed streams and the prominent role of water temperature and substrate stability in determining longitudinal patterns of macroinvertebrate community structure. The GAMs are proposed as a tool for predicting changes of zoobenthic communities in glacier-fed streams under climate or hydrological change scenarios.

1. Bluegill sunfish (Lepomis macrochirus) dominate fish assemblages of small lakes and ponds throughout the eastern United States and may play a major role in structuring aquatic communities. We examined the impact of adult bluegill on... more

1. Bluegill sunfish (Lepomis macrochirus) dominate fish assemblages of small lakes and ponds throughout the eastern United States and may play a major role in structuring aquatic communities. We examined the impact of adult bluegill on amphibian density by stocking bluegill at a range of densities into partitions of an experimental pond in which amphibians were free to colonize. 2. Adult bluegill had a major impact on the amphibian assemblage. By the end of the experiment, gray treefrog (Hyla versicolor) tadpoles were nine times less abundant, and red-spotted newt (Notophthalmus viridescens) adults were three times less abundant in the presence of adult bluegill than in their absence. In contrast, bullfrog (Rana catesbeiana) tadpoles tended to increase in the presence of adult bluegill. Adult bluegill also had a negative effect on the abundance of predaceous aquatic insects. 3. There was no indication that interactions among amphibians were significant in determining the above patterns. We suggest that the strong impact of adult bluegill resulted from a combination of direct and indirect effects on amphibian larvae and predaceous aquatic insects.

This paper introduces a new approach for setting streamflow-based river ecosystem management targets and this method is called the 'Range of Variability Approach' (RVA). The proposed approach derives from aquatic ecology theory concerning... more

This paper introduces a new approach for setting streamflow-based river ecosystem management targets and this method is called the 'Range of Variability Approach' (RVA). The proposed approach derives from aquatic ecology theory concerning the critical role of hydrological variability, and associated characteristics of timing, frequency, duration, and rates of change, in sustaining aquatic ecosystems. The method is intended for application on rivers wherein the conservation of native aquatic biodiversity and protection of natural ecosystem functions are primary river management objectives. 2. The RVA uses as its starting point either measured or synthesized daily streamflow values from a period during which human perturbations to the hydrological regime were negligible. This streamflow record is then characterized using thirty-two different hydrological parameters, using methods defined in Richter et al. (1996). Using the RVA, a range of variation in each of the thirty-two parameters, e.g. the values at Ϯ 1 standard deviation from the mean or the twenty-fifth to seventy-fifth percentile range, are selected as initial flow management targets. 3. The RVA targets are intended to guide the design of river management strategies (e.g. reservoir operations rules, catchment restoration) that will lead to attainment of these targets on an annual basis. The RVA will enable river managers to define and adopt readily interim management targets before conclusive, long-term ecosystem research results are available. The RVA targets and management strategies should be adaptively refined as suggested by research results and as needed to sustain native aquatic ecosystem biodiversity and integrity.

1. Aquatic ecosystems in Northern Europe are expected to face increases in temperature and water colour (TB) in future. While effects of these factors have been studied separately, it is unknown whether and how a combination of them might... more

1. Aquatic ecosystems in Northern Europe are expected to face increases in temperature and water colour (TB) in future. While effects of these factors have been studied separately, it is unknown whether and how a combination of them might affect phenological events and trophic interactions. 2. In a mesocosm study, we combined both factors to create conditions expected to arise during the coming century. We focused on quantifying effects on timing and magnitude of plankton spring phenological events and identifying possible mismatches between resources (phytoplankton) and consumers (zooplankton). 3. We found that the increases in TB had important effects on timing and abundance of different plankton groups. While increased temperature led to an earlier peak in phytoplankton and zooplankton and a change in the relative timing of different zooplankton groups, increased water colour reduced chlorophyll-a concentrations. 4. Increased TB together benefitted cladocerans and calanoid copepods and led to stronger top-down control of algae by zooplankton. There was no sign of a mismatch between primary producers and grazers as reported from other studies. 5. Our results point towards an earlier onset of plankton spring growth in shallow lakes in future with a stronger top-down control of phytoplankton by zooplankton grazers.

A total of 31 sites were collected in the north and middle basins of Capitol Lake and one in Percivial Creek. Twenty-seven of the sites sampled in Capitol Lake had live NZMS present. Of the 3 sites in the middle basin, 2 had only dead... more

A total of 31 sites were collected in the north and middle basins of Capitol Lake and one in Percivial Creek. Twenty-seven of the sites sampled in Capitol Lake had live NZMS present. Of the 3 sites in the middle basin, 2 had only dead NZMS shells present while the southernmost one had none present. Based on a number of the NZMS at the 27 live sites in the lake a density contour map was drawn. The highest densities of the NZMS occur in the north basin of Capitol Lake from the outlet of the lake at the dam to the east along the shoreline. Additional areas of high densities of the NZMS occur in the southern part of the north basin just north of the railroad grade and along the east bank of the north part of the middle basin. The lowest densities of the NZMS are found in three areas of the north basin and the southern end of the middle basin. No NZMS were found in the southernmost part of the middle basin

1. This paper is a synthesis of a special issue on groundwater biodiversity with a focus on obligate subterranean species, the stygobionts. The series of papers constitutes a great leap forward in assessing and understanding biodiversity... more

1. This paper is a synthesis of a special issue on groundwater biodiversity with a focus on obligate subterranean species, the stygobionts. The series of papers constitutes a great leap forward in assessing and understanding biodiversity patterns because of the use of large quantitative data sets obtained over a broad geographic scale. They also represent a conceptual shift, away from a purely taxonomic and phylogenetic focus to the analysis of whole groundwater assemblages. 2. The general patterns emerging for groundwater fauna are: very high levels of endemism, low local diversity relative to regional diversity, a limited number of lineages, occurrence of many relicts, and truncated food webs with very few predators. 3. b-Diversity is at least as important as a-diversity in determining total richness at different scales (aquifer, basin and region) and overall taxa richness increases across spatial scales. 4. Advances in understanding groundwater biodiversity patterns further include identification of several important factors related to geology and hydrology that determine the composition of European stygobiotic assemblages. 5. Important challenges for future research include improving sampling strategies, filling gaps in sampling coverage, intensifying research on theoretical and statistical models, and including functional and genetic diversity components in biodiversity assessments. 6. Strategies are proposed for protecting groundwater biodiversity and an argument is made to integrate biodiversity in groundwater management. Applying principles such as complementarity and flexibility for groundwater biodiversity conservation is a major step toward delineating a reserve network that maximise species representation at the European scale.

this article is about all Ultimate Guide to Marimo Moss Balls. In this article talks all about keeping, cultivating, carrying and tips of marimo moss balls in the freshwater tank. Please visit our site aquascaper.org for more information... more

this article is about all Ultimate Guide to Marimo Moss Balls. In this article talks all about keeping, cultivating, carrying and tips of marimo moss balls in the freshwater tank. Please visit our site aquascaper.org for more information about aquarium moss plants

This research work evaluates the impact of stormwater infiltration on the removal of organics, solids, nitrogen and phosphorus in a LECA-based horizontal subsurface flow constructed wetland. Stormwater runoff for the period between... more

This research work evaluates the impact of stormwater infiltration on the removal of organics, solids, nitrogen and phosphorus in a LECA-based horizontal subsurface flow constructed wetland. Stormwater runoff for the period between January 2008 and June 2010 (30 months) was estimated for the drainage basin of the Vila Fernando wastewater treatment plant (constructed wetland system) and it was observed proportionality between the increase in surface runoff and the infiltration flow rate that reached the plant. The average stormwater infiltration rate that reached the plant was 67.4 m(3) d(-1) (77% of the influent flow rate into the plant). The 30 month monitoring campaign set up at one of the reed beds showed that stormwater infiltration led to a high variation of the hydraulic loading rate (HLR) throughout the bed, which affected its performance in the removal of organic matter, suspended solids and nitrogen. For a HLR below 20 cm d-1 the removal efficiencies for BOD5, COD and TSS doubled. The removal of nitrogen was too low and was associated with the weak development of nitrifying biofilm and the poor growth of reeds. However, it was observed a good relationship between the applied and removed loads for most of the parameters, which seems to indicate that the organic, solid, nitrogen and phosphorus loading rates influenced the respective removal rates. The use of a bed material with high specific surface area, such as LECA, can only improve the treatment capacity of horizontal subsurface flow systems if the organic and solid loading rates, as well as the HLR, can be effectively controlled.

Aim We investigated genetic variation of Irish pike populations and their relationship with European outgroups, in order to elucidate the origin of this species to the island, which is largely assumed to have occurred as a humanmediated... more

Aim We investigated genetic variation of Irish pike populations and their relationship with European outgroups, in order to elucidate the origin of this species to the island, which is largely assumed to have occurred as a humanmediated introduction over the past few hundred years. We aimed thereby to provide new insights into population structure to improve fisheries and biodiversity management in Irish freshwaters.

1. The effect of total nitrogen (TN) and phosphorus (TP) loading on trophic structure and water clarity was studied during summer in 24 field enclosures fixed in, and kept open to, the sediment in a shallow lake. The experiment involved a... more

1. The effect of total nitrogen (TN) and phosphorus (TP) loading on trophic structure and water clarity was studied during summer in 24 field enclosures fixed in, and kept open to, the sediment in a shallow lake. The experiment involved a control treatment and five treatments to which nutrients were added: (i) high phosphorus, (ii) moderate nitrogen, (iii) high nitrogen, (iv) high phosphorus and moderate nitrogen and (v) high phosphorus and high nitrogen. To reduce zooplankton grazers, 1 + fish (Perca fluviatilis L.) were stocked in all enclosures at a density of 3.7 individuals m )2 . 2. With the addition of phosphorus, chlorophyll a and the total biovolume of phytoplankton rose significantly at moderate and high nitrogen. Cyanobacteria or chlorophytes dominated in all enclosures to which we added phosphorus as well as in the high nitrogen treatment, while cryptophytes dominated in the moderate nitrogen enclosures and the controls. 3. At the end of the experiment, the biomass of the submerged macrophytes Elodea canadensis and Potamogeton sp. was significantly lower in the dual treatments (TN, TP) than in single nutrient treatments and controls and the water clarity declined. The shift to a turbid state with low plant coverage occurred at TN >2 mg N L )1 and TP >0.13-0.2 mg P L )1 . These results concur with a survey of Danish shallow lakes, showing that high macrophyte coverage occurred only when summer mean TN was below 2 mg N L )1 , irrespective of the concentration of TP, which ranged between 0.03 and 1.2 mg P L )1 . 4. Zooplankton biomass and the zooplankton : phytoplankton biomass ratio, and probably also the grazing pressure on phytoplankton, remained overall low in all treatments, reflecting the high fish abundance chosen for the experiment. We saw no response to nutrition addition in total zooplankton biomass, indicating that the loss of plants and a shift to the turbid state did not result from changes in zooplankton grazing. Shading by phytoplankton and periphyton was probably the key factor. 5. Nitrogen may play a far more important role than previously appreciated in the loss of submerged macrophytes at increased nutrient loading and for the delay in the reestablishment of the nutrient loading reduction. We cannot yet specify, however, a

We evaluated the influence of environmental integrity and the potential as bioindicator of larval stages of species of Trichoptera in 20 streams of first to fourth order in the Pindaı´ba river basin, Mato Grosso, Central Brazil. We... more

We evaluated the influence of environmental integrity and the potential as bioindicator of larval stages of species of Trichoptera in 20 streams of first to fourth order in the Pindaı´ba river basin, Mato Grosso, Central Brazil. We measured stream integrity with the habitat integrity index (HII), establishing three levels of conservation: preserved, altered and impacted environments. We used (i) simple regression to assess the effect of habitat integrity on species abundance of Trichoptera and (ii) the indicator species analysis (IndVal) to assess the potential as bioindicator of each species. We found that 12 morphospecies showed relationship with HII: six species were bioindicators of preserved and two species of altered environments. Morphospecies that showed relationship in the two analyses (i and ii) were considered strong bioindicators, considering that the other species supported higher environmental variation, becoming evident that loss of physical structure reduces the abundance of organisms specialized in preserved environments. The results showed that the distribution and abundance of trichopterans can be an indicator of habitat integrity. Trichopteran species have bioindicator potential, corroborating the hypotheses of this work that abundance
of organisms will be smaller in environments with low integrity, and that many species are specific to preserved environments, disappearing from impacted environments, and also characteristic species of altered environments.

Dissolved oxygen (DO) is probably the most important parameter related to water quality and biological habitat in aquatic environments. In situ DO sensors are some of the most valuable tools used by scientists and engineers for the... more

Dissolved oxygen (DO) is probably the most important parameter related to water quality and biological habitat in aquatic environments. In situ DO sensors are some of the most valuable tools used by scientists and engineers for the evaluation of water quality in aquatic ecosystems. Presently, we cannot accurately measure DO concentrations under variable temperature and pressure conditions. Pressure and temperature influence polarographic and optical type DO sensors compared to the standard Winkler titration method. This study combines laboratory and field experiments to compare and quantify the accuracy and performance of commercially available macro and micro Clark-type oxygen sensors as well as optical sensing technology to the Winkler method under changing pressure and temperature conditions. Field measurements at various lake depths revealed sensor response time up to 11 min due to changes in water temperature, pressure, and DO concentration. Investigators should account for transient response in DO sensors before measurements are collected at a given location. We have developed an effective model to predict the transient response time for Clark-type oxygen sensors. The proposed procedure increases the accuracy of DO data collected in situ for profiling applications.

1. We observed that the dragonfly species Sympetrum flaveolum, S. striolatum, S. sanguineum, S. meridionale and S. danae were attracted by polished black gravestones in a Hungarian cemetery. 2. The insects showed the same behaviour as at... more

1. We observed that the dragonfly species Sympetrum flaveolum, S. striolatum, S. sanguineum, S. meridionale and S. danae were attracted by polished black gravestones in a Hungarian cemetery. 2. The insects showed the same behaviour as at water: (i) they perched persistently in the immediate vicinity of the chosen gravestones and defended their perch against other dragonflies; (ii) flying individuals repeatedly touched the horizontal surface of the shiny black tombstones with the ventral side of their body; (iii) pairs in tandem position frequently circled above black gravestones. 3. Tombstones preferred by the dragonflies were in the open and had an area of at least 0.5 m 2 with an almost horizontal, polished, black surface and with at least one perch in their immediate vicinity. 4. Using imaging polarimetry, we found that the black gravestones, like smooth water surfaces, reflect highly and horizontally polarized light. 5. In double-choice field experiments with various test surfaces, we showed that the dragonflies attracted to shiny black tombstones display positive polarotaxis and, under natural conditions, detect water by means of the horizontally polarized reflected light. This, and the reflection-polarization characteristics of black gravestones, explain why these dragonflies are attracted to black tombstones. 6. If females attracted to the black gravestones oviposit on them, the latter constitute ecological traps for dragonflies that are not close to water.

Defaunation, originally conceived as the loss of large vertebrates due to hunting or fragmentation, has been widely used in conservation studies yet the term has been arbitrarily used and poorly defined. Here we refine this term by... more

Defaunation, originally conceived as the loss of large vertebrates due to hunting or fragmentation, has been widely used in conservation studies yet the term has been arbitrarily used and poorly defined. Here we refine this term by creating a quantitative index that can be used to compare ecological communities over large zoogeographical regions. We propose a defaunation index (D) as a weighted measure of dissimilarity between the current assemblage of a given location and a reference assemblage that represents a historical and/or unperturbed state. We analyzed the index by means of three case studies that included two empirical assessments of mammal communities in Neotropical rainforests and one hypothetical example, encompassing a variety of criteria to quantify differences in species density and importance. These cases illustrate the broad range of index applicability and show that incorporating functional differences among species, such as those based on body size, conservation status or evolutionary originality can add important information beyond simply species richness.

The pet trade in freshwater crustaceans, including crayfish, has grown rapidly in recent decades and become an important pathway for introducing new non-indigenous species into Europe. This paper provides the first overview of... more

The pet trade in freshwater crustaceans, including crayfish, has grown rapidly in recent decades and become an important pathway for introducing new non-indigenous species into Europe. This paper provides the first overview of non-indigenous crayfish species (NICS) traded as ornamental and their potential impact in the Czech Republic, which is the
second leading importer into Europe. The paper presents a full list of traded crayfish species, their market availability, and trade names or misnomers used in the country. In total, 27 crayfish species from all three families are advertised and marketed, of which Astacus astacus is the only indigenous species.
Only three NICS were recognized as very common on
the market. The invasiveness and risk associated with
ornamental crayfish trade were assessed using the
Freshwater Invertebrate Invasiveness Scoring Kit.
Five NICS were classified into the high-risk category,
the highest score being for Procambarus fallax f.
virginalis. The invasiveness of crayfish indigenous to
North America is significantly greater than that of
crayfish from the rest of the world, and therefore
regulation in this regard is recommended.

In this study, local assessment of water quality is used to illustrate key features of aquatic environments, and demonstrate how human activities on the landscape can influence water quality in both positive and negative ways. Poor water... more

In this study, local assessment of water quality is used to illustrate key features of aquatic environments, and demonstrate how human activities on the landscape can influence water quality in both positive and negative ways. Poor water quality can be the result of natural processes but more associated with human activities and is closely linked to industrial development. Iligan City is considered a home of majestic waterfalls and other bodies of water. Thus, this study was conducted to assess the water quality of Timoga River (downstream), Buruun, Iligan City in terms of physico-chemical parameters (temperature, water salinity, dissolved oxygen and pH); nutrient analyses (phosphates, nitrates and nitrites) and bacteriological analysis (coliform load) using standard methods. Results of this study yield pH values ranging from 9.11 to 9.72 hence, indicating poor water quality for all the sampling stations since, based on EPA standard (2007) pH values between 6.5 and 8.5 are the pH values indicating good water quality. A possibility for the observed high alkalinity of water in the area is the presence of man-made laundry well near the river used by community residents for washing clothes, washing dishes and for cleaning purposes. The water coming from the well containing soaps, detergents and " bleach, " Sodium Hypochlorite (NaOCl) flows directly to the river system and the rise of water level may cover the well especially during high tide. Alkaline compounds as discharges from industries are also great contributors to water alkalinity (increase in pH). Moreover, based on the EPA guidelines for healthy surface, waters dissolved oxygen concentration-DO (mg/L) should be at least 8, here sampling stations yield values below the standard. In terms of nutrient analyses, nitrate concentrations were relatively high compared to the standard of no more than 0.38 mg/L, while the nitrite concentration is relatively low. Phosphate concentrations for all stations were also fairly higher than 10.0µg/L. In terms of bacteriological analyses, the bacteria present were Escherichia coli and Enterobacter sp. With this information, appropriate actions should be disseminated in order to address the need in taking care of these water resources which is vital to environment and human health.

Agriculture, environment, industry, and millions of households in the western US and northern Mexico depend on the Colorado River, which is facing increasing water shortages due to climate change and rising demand. Collaborative... more

Agriculture, environment, industry, and millions of households in the western US and northern Mexico depend on the Colorado River, which is facing increasing water shortages due to climate change and rising demand. Collaborative governance will likely be key to solving allocation issues and achieving sustainable water use but has recently faced multiple challenges. This research integrates concepts from institutional, adaptive govern-ance, and bargaining theories to analyze barriers and facilitators to collaborative governance in the drought contingency plan (DCP) process for the lower Colorado River basin from an Arizona stakeholder's perspective. The DCP is ultimately an effort to create a set of rules to prevent and address shortages in the basin. Through a content analysis of public meetings of the Central Arizona Project's governing board, we find a collective DCP or future related policy may be possible. But barriers to collaborative governance have intensified over time, hindering the process and making an agreement increasingly unlikely. The process is a perfect example of the interplay between rules and norms, and the issues that arise when norms underlying rules are interpreted differently. Our analysis provides insights for the design of collaborative water governance, including that conducting an analysis of power dynamics among the stakeholders would advance the DCP process. We ultimately argue that the Colorado River basin would benefit from a transition towards adaptive governance, and that our recommendations to improve collaboration are an important initial step. Additionally, our results reveal areas that require more empirical research, including understanding how to prepare for policy windows, rapid trust building among stakeholders, and theory building related to equity and marginalization in collaborative gov-ernance processes.

1. Submerged macrophyte and phytoplankton components of eutrophic, shallow lakes have frequently undergone dynamic changes in composition and abundance with important consequences for lake functioning and stability. However, because of a... more

1. Submerged macrophyte and phytoplankton components of eutrophic, shallow lakes have frequently undergone dynamic changes in composition and abundance with important consequences for lake functioning and stability. However, because of a paucity of long-term survey data, we know little regarding the nature, direction and sequencing of such changes over decadal-centennial or longer timescales. 2. To circumvent this problem, we analysed multiple (n = 5) chronologically correlated sediment cores for plant macro-remains and a single core for pollen and diatoms from one small, shallow, English lake (Felbrigg Hall Lake, Norfolk, U.K.), documenting 250 years of change to macrophyte and algal communities. 3. All five cores showed broadly similar stratigraphic changes in macrophyte remains with three distinct phases of macrophyte development: Myriophyllum-Chara-Potamogeton (c. pre-1900), to Ceratophyllum-Chara- Potamogeton (c. 1900Potamogeton (c. -1960 and finally to Zannichellia-Potamogeton (c. post-1960). Macrophyte species richness declined from at least 10 species pre-1900 to just four species at the present day. Additionally, in the final Zannichellia-Potamogeton phase, a directional shift between epi-benthic and phytoplanktonbased primary production was indicated by the diatom data. 4. Based on macrophyte-seasonality relationships established for the region, concomitant with the final shift to Zannichellia-Potamogeton, we infer a reduction in the seasonal duration of plant dominance (plant-covered period). Furthermore, we hypothesise that this change in species composition resulted in a situation whereby macrophyte populations were seasonally 'sandwiched' between two phytoplankton peaks in spring and late summer as observed in the contemporary lake. 5. We suggest that eutrophication-induced reductions in macrophyte species richness, especially if the number of plant-seasonal strategies is reduced, may constrict the plant growing season. In turn, this may render a shallow lake increasingly vulnerable to seasonal invasions of phytoplankton resulting in further species losses in the plant community. Thus, as part of a slow (over perhaps 10-100s of years) and self-perpetuating process, macrophytes may be gradually pushed out by phytoplankton without the need for a perturbation as required in the alternative stable states model of plant loss.

Most of the science and practice of conservation planning has focused on terrestrial environments, just as this book has, with similarly threatened marine and freshwater systems receiving less attention. In contrast to land, anthropogenic... more

Most of the science and practice of conservation planning has focused on terrestrial environments, just as this book has, with similarly threatened marine and freshwater systems receiving less attention. In contrast to land, anthropogenic changes to marine and freshwater systems are less easily observed and, until recently, the phrase " out of sight, out of mind " aptly applied to the conservation of these systems. As human impacts on marine and freshwater systems have become increasingly apparent (e.g., fisheries collapses), there has been an increasing realization that these ecosystems require protection, better resource management, and conservation. Biodiversity in marine and freshwater is declining alarmingly, and humans are starting to feel the effects of reductions in ecosystem services. Increased conservation of marine and freshwater systems is therefore necessary, and a key part of these efforts will be conservation planning. The goals of this chapter are to provide an overview of established good practices in marine and freshwater conservation planning, highlight distinctive characteristics of marine and freshwater systems important for their conservation, and place these systems in the broader framework of conservation planning. We highlight elements of marine and freshwater systems that differ both from each other and from terrestrial systems, and discuss how these differences influence approaches to planning. Also, despite some differences between aquatic and terrestrial systems, many of the principles, lessons, tools, and techniques for terrestrial conservation planning described in other chapters of this book can be adapted to marine and freshwater systems. We also pinpoint some emerging and cutting-edge conservation issues and practices, but the predominant focus of this chapter is on established good practices.

Rainwater harvesting is a technique used for collecting, storing, and using rainwater for potable and various non-potable uses In responses to cope up with the ever-increasing water crisis, particularly freshwater crisis due to various... more

Rainwater harvesting is a technique used for collecting, storing, and using rainwater for potable and various non-potable uses In responses to cope up with the ever-increasing water crisis, particularly freshwater crisis due to various anthropogenic causes and also groundwater depletion problem resulting in the over-extraction of it, harvesting rainwater is now considering as one of the sustainable solutions for different countries or regions of the world that receive a good amount of rain annually. This system is not a new practice as it was a common practice in ancient India and Egypt used for households and agricultural purposes and in Thailand; this practice has prevailed for centuries. But, in recent times, the system, being clean and healthy sources of water, has gained much more popularity in different parts of the world where rainfalls are available in sufficient quantities, taking into consideration of the portable and freshwater inadequacy.

"Plastics and their chemicals are in every body of water and in every human body. Usual scientific measurements of toxicity, the ability to track contaminants, and causal models fore estimating long-term effects are failing to account for... more

"A water body is an ecosystem, not just a carrier of water that is susceptible to pollution. It is a system unto its own that is dependent on plant and animal activity around it. The problem isn’t always pollution and the solution isn’t... more

"A water body is an ecosystem, not just a carrier of water that is susceptible to pollution. It is a system unto its own that is dependent on plant and animal activity around it. The problem isn’t always pollution and the solution isn’t always separation of humans from nature. The solution lies in nurturing a healthy, democratic and accountable relationship between humans and their natural habitat, for the sustainable survival of both. The notion of protecting the environment from pollution by rigidly divorcing it from humans who live off it is problematic. There are some basic assumptions this notion is guided by, which need to be questioned. Who is causing the real pollution? Why is it that the
people who are in direct contact with the environment are always the ones fingers are pointed at? "

Through this assessment, the authors and the United Nations Environment Programme (UNEP) secretariat are providing an objective evaluation and analysis of the pan-European environment designed to support environmental decision-making at... more

Through this assessment, the authors and the United Nations Environment Programme (UNEP) secretariat are providing an objective evaluation and analysis of the pan-European environment designed to support environmental decision-making at multiple scales. In this assessment, the judgement of experts is applied to existing knowledge to provide scientifically credible answers to policy-relevant questions. These questions include, but are not limited to the following:
• What is happening to the environment in the pan-European region and why?
• What are the consequences for the environment and the human population in the pan-European region?
• What is being done and how effective is it?
• What are the prospects for the environment in the future?
• What actions could be taken to achieve a more sustainable future?

In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological... more

In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic communities (lakes); endemism and diversity (ancient lakes); threatened, sensitive species (oxbow lakes, SWE); diverse, reduced littoral (reservoirs); cold-adapted species (Boreal and Arctic fwh); endemism, depauperate (Antarctic fwh); flood pulse, intermittent wetlands, biggest river basins (tropical fwh); variable hydrologic regime-periods of drying, flash floods (arid-climate fwh). Selected impacts: eutrophication and other pollution, hydrologic modifications, overexploitation, habitat destruction, invasive species, salinization. Climate change is a threat multiplier, and it is important to quantify resistance, resilience, and recovery to assess the strategic role of the different types of freshwater ecosystems and their value for biodiversity conservation. Effective conservation solutions are dependent on an understanding of connectivity between different freshwater ecosystems (including related terrestrial, coastal and marine systems).

This work is part of a broader, multi-year investigation of Maui Island’s freshwater resources. Maui Island faces multiple resource constraints, including water, land, energy, and capital, and these resource constraints could become... more

This work is part of a broader, multi-year investigation of Maui Island’s freshwater resources. Maui Island faces multiple resource constraints, including water, land, energy, and capital, and these resource constraints could become relevant over the next forty years. Not only does Maui face potential changes to its water and other systems due to external factors beyond its control, like anthropogenic and other climate changes, but Maui also could make developmental choices that will impact how its resource systems interact. In particular, this work looks at Maui’s freshwater systems as they relate to energy, waste, and environmental systems. This report provides a foundation for future scenario analysis on the island that will aim to characterize potential synergies and hazards of choices like increased food production, local fuel production, and increased use of renewable energies.

1. Copepoda, Ostracoda and`Cladocera`are important meiobenthic Crustacea which can be both numerically abundant and species rich in running waters. Harpacticoids and ostracods are well adapted to benthic life because they are typical... more

1. Copepoda, Ostracoda and`Cladocera`are important meiobenthic Crustacea which can be both numerically abundant and species rich in running waters. Harpacticoids and ostracods are well adapted to benthic life because they are typical crawlers, walkers, and burrowers. Many cladocerans are substratum dwellers, but most benthic species among these can also swim. Cyclopoids which are generally good swimmers are nevertheless often bottom frequenters and actively colonise sediment interstices (the hyporheic zone). 2. The subclass Copepoda includes 10 orders. With 53 families, the order Harpacticoida dominates the benthos. Only five of these families are represented in fresh waters (ca. 1 000 species and subspecies). The order Cyclopoida includes 12 families of which the Cyclopidae is well represented in freshwater habitats with 900 species and subspecies. Freshwater Ostracods belong to the order Podocopida (5 000 species) with three superfamilies occurring in running fresh waters. The group`Cladocera`contains four orders, 12 families, more than 80 genera, and 450±600 freshwater species. Most of the benthic species are found in the families Chydoridae (39 genera), Macrothricidae, Ilyocryptidae and Sididae. 3. For each of the three major taxa, morphological characteristics are presented, specimen collection and preparation are described and references to available taxonomical keys are provided. 4. Biological characteristics are extremely diverse among and within the three taxa, resulting in a great variety of strategies in meiobenthic crustaceans. Characteristics of reproduction, sexual dimorphism, cyclomorphosis and population parameters (i.e. clutch size, lifespan, growth, moulting) are provided for some of the most common species. 5. Important differences between the three main taxa were found at the species level. Ecological requirements such as hydraulic microhabitats and geomorphologic features of the streambed are the major determinants of species diversity and abundance for benthic microcrustacea of lotic habitats. Many studies on the ecology of these communities are limited by a lack of knowledge of the life history characterisitics of lotic (especially interstitial) crustacean populations.

The Mackenzie River is the largest north-flowing river in North America. It is the longest river in Canada and it drains a watershed that occupies nearly 20 per cent of the country. The river is big and complex. It is also... more

Cette étude bibliographique porte sur l'ichtyofaune des eaux continentales du Maroc et a pour but de fournir une liste préliminaire des espèces autochtones et introduites. L'ichtyofaune du Maroc, qui compte 30 espèces autochtones et 16... more

Cette étude bibliographique porte sur l'ichtyofaune des eaux continentales du Maroc et a pour but de fournir une liste préliminaire des espèces autochtones et introduites. L'ichtyofaune du Maroc, qui compte 30 espèces autochtones et 16 introduites, est menacée de disparition à cause de plusieurs facteurs dont la pollution urbaine ou industrielle, la sécheresse, la construction de barrages, le détournement des cours d'eau et la surpêche. Des mesures doivent être prises pour une meilleure conservation de cette richesse ichtyologique.

In this paper, we describe a non-marine mollusk fauna deriving from late middle Miocene (late Serravallian; Sarmatian) deposits of western Serbia. The assemblage encompasses a diverse land snail fauna with twenty-four species, along with... more

In this paper, we describe a non-marine mollusk fauna deriving from late middle Miocene (late Serravallian; Sarmatian) deposits of western Serbia. The assemblage encompasses a diverse land snail fauna with twenty-four species, along with four species of freshwater pulmonate gastropods and one bivalve species. While the aquatic snails are ubiquitous elements in Europe during the middle Miocene, the terrestrial gastropod fauna, consisting of both common and rare species, offers the first comprehensive insight into land snail diversity on the Balkan Peninsula during that time and permits conclusions on regional biogeography. The fauna shows high affinities to the middle Miocene faunas of central Europe and shares only few elements with western and eastern European and Anatolian assemblages. Ecologically, the freshwater mollusks point to a standing or slowing moving, probably highly vegetated, lacustrine environment. The land snails indicate the presence of humid forests around Lake Vračević, which is in line with current climatic reconstruction for the Sarmatian of southeastern Europe. ?Vertigo vracevicensis Neubauer & Harzhauser sp. nov. and Pisidium mionicense Neubauer, Harzhauser & Mandic sp. nov. are introduced as new species. Discus costatus (Gottschick, 1911) is shown to be a junior objective synonym of Discus solarioides (Sandberger, 1872). •

A B S T R A C T The planting of forests has been met with both scepticism and support in international forest policy and management fora. Discussions regarding the values of plantations for extrinsic purposes such as timber supply, carbon... more

A B S T R A C T The planting of forests has been met with both scepticism and support in international forest policy and management fora. Discussions regarding the values of plantations for extrinsic purposes such as timber supply, carbon sequestration, water quality and biodiversity conservation, reveal widely varying opinions across and within different settings. Recent research highlights the role of planted forests in providing multiple ecosystem services to human society. However, there has been little assessment of ecosystems services, partly due to lack of suitable frameworks and evaluation tools. Planted forests generally have low ecosystem services values initially and are more vulnerable to erosion and other impacts of mismanagement than natural forests. Careful monitoring of change in ecosystem services values over time is therefore vital to investors and all stakeholders in plantations. Drawing on lessons derived from ecosystem services assessment for various land use types, here we propose an easy-to-apply framework to assess ecosystem services from planted forests that could be used in various planted forest types around the world. A necessary next step for researchers and practitioners is to test the proposed framework under various settings.

Water is an essential component of human right, yet legal framework of its usage, except for navigation is disproportionally underdeveloped. This allows countries to abuse flaws in this framework, which in turn has a negative impact on... more

Water is an essential component of human right, yet legal framework of its usage, except for navigation is disproportionally underdeveloped. This allows countries to abuse flaws in this framework, which in turn has a negative impact on people. Approaches taken by actors involved in the process of sharing fresh water might determine the future of our planet. The human kind's coexistence (peaceful or non-peaceful) is dependent on that.