scholarly journals The Macrophyte Index for Rivers (MIR) as an Advantageous Approach to Running Water Assessment in Local Geographical Conditions

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 108 ◽  
Author(s):  
Krzysztof Szoszkiewicz ◽  
Szymon Jusik ◽  
Karol Pietruczuk ◽  
Daniel Gebler

The Macrophyte Index for Rivers (MIR) was developed in 2007, and it was one of the first biological methods developed in Poland under the requirements of the Water Framework Directive to assess the ecological status of running waters. It is based on the quantitative and qualitative evaluation of 153 indicator taxa. The aim of this study was to evaluate the ability of the MIR method to detect trophic degradation in rivers and to compare its efficiency with other macrophyte metrics. Our investigation was based on 100 sites, representing a very clear gradient from near oligotrophic to eutrophic conditions. The results showed that macrophytes can be distinguished in terms of their ecological requirements for nutrient concentration in water, and this can be used to develop an effective system of freshwater assessment. The MIR was shown to be the indicator most strongly correlated with various forms of nutrients, and it was demonstrated that calibration of the macrophyte method to local biogeographical conditions resulted in greater effectiveness of the assessment method.

Author(s):  
Claus Orendt

Based on data from monitoring in north-east Germany (Land Brandenburg) over a decade, chironomid taxa and their abundances were analysed for their preferences for certain running water types and degradation levels. A detrended correspondence analysis (DCA) revealed that the distribution of the taxa was determined by both, degradation level and water body type. A series of taxa was positively or negatively correlated to degradation, however, frequently only in certain water body types. In other types, they played no major role or were evenly distributed along the degradation gradient. Higher correlations were found for taxa favouring ‘good’ and 'poor' or 'bad' conditions than for preferers of ‘moderate’ status. The results allow to validate indices and weigths of indicators derived from high frequencies of the taxa in certain one or more quality class(es). The preferred ocurrencies elaborated have to be discussed or tested for plausiblity before using or evaluating powerful indicator taxa for classifications or revisions in assessment practice. A reduction of the taxonomical precision to genus level lowered the statistical significance and requires careful examination of the species preferences of the genus.


2014 ◽  
Vol 186 (9) ◽  
pp. 5501-5517 ◽  
Author(s):  
Hanna Ciecierska ◽  
Agnieszka Kolada

Author(s):  
Asea Timus ◽  
N. Croitoru

Every year, the demand of ecological products in the world is increasing more and more. Republic of Moldova also aspires to expand the areas of agricultural crops to get production with the "ecological" status. The sweet corn, is one of these cultures and every year the areas increase. However, because of the considerable develop of harmful insects on cultural fields, the damage reaches up to 15-20 % and more it is necessary to take measures of struggle. One of these, is a biological method and in this case it has appeared effective. For the period of sweet corn cultivation, excepting for the technology observance of cultivation of the given culture, there have been used biological methods of struggle against harmful insects. Depending on climatic conditions of each zone of the country where it is grown up this culture, different species of harmful insects develop. In R. Moldova, begining with year 2000, have been registered the following harmful species of insects on sweet corn: Aphis spp. (Aphididae); Agrotis spp. (Elateridae); Blaps halophila Fisch. (Tenebrionidae); Phylotreta spp. (Chrysomelidae); Helicoverpa armigera Hubner (Noctuidae) Ostrinia nubilalis Hb. (Pyraustidae). The constant useful fauna which develops due to these harmful species is: Nabis spp. (Miridae); Chrysopa spp., (Chrysopidae); Coccinella spp. (Coccinelidae) and others. That is why, annually are let out individuals from species Trichogramma evanescens W., to reduce the number of harmful species H. armigera Hubner. This species annually damages on different cultures, including on sweet corn. The results on released trichogrammas in 2005, for struggle against harmful species H. armigera Hubner, are presented in this work.


2021 ◽  
Vol 4 ◽  
Author(s):  
Sara Atienza Casas ◽  
Markus Majaneva ◽  
Thomas Jensen ◽  
Marie Davey ◽  
Frode Fossøy ◽  
...  

Biodiversity assessments using molecular identification of organisms through high-throughput sequencing techniques have been a game changer in ecosystem monitoring, providing increased taxonomic resolution, more objective identifications, potential cost reductions, and reduced processing times. The use of DNA metabarcoding of bulk samples and environmental DNA (eDNA) is now widespread but is not yet universally implemented in national monitoring programs. While bulk sample metabarcoding involves extraction of DNA from organisms in a sample, eDNA analysis involves obtaining DNA directly from environmental samples, which can include microorganisms, meiofauna-size taxa and macrofauna traces such as larval stages, skin and hair cells, gametes, faeces and free DNA bound to particles. In Norway, freshwater biomonitoring in compliance with the EU Water Framework Directive (WFD) is conducted on several administrative levels, including national monitoring programs for running water, small and large lakes. These programs typically focus on a fraction of the actual biodiversity present in the monitored habitats (Weigand 2019). DNA metabarcoding of both bulk samples and eDNA samples are relevant tools for future freshwater biomonitoring in Norway. The aim of this PhD project is to develop assessment protocols based on DNA-metabarcoding and eDNA of benthic invertebrates, microcrustaceans and fish that can be used as standard biomonitoring tools to assess the ecological condition of lakes. The main topics addressed will be: - Development of protocols throughout the eDNA-metabarcoding workflow (i.e. sampling, filtration, preservation, extraction, amplification and sequencing) suitable to execute biodiversity assessments and determine the ecological status of lakes. - Comparison of the results obtained using molecular tools and traditional morphology-based approaches in order to assess the feasibility of such techniques to be incorporated as standard biomonitoring tools, such as the ones implemented under the provisions of the WFD. - Evaluate the effect of improved taxonomic resolution from molecular techniques on determining the ecological status of lakes, both by broadening the number of taxa analyzed and by identifying more taxa to species level. - Assess the feasibility of using eDNA extracted from water samples, taken at different depths and fish densities, to measure fish abundance/biomass as a proxy to calculate the ecological quality indices regulated in the WFD. - Analyze the coverage and resolution provided by reference libraries for certain taxa, such as crustacea, in order to assess the reliability and precision of taxonomic assignments.


Diversity ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 458
Author(s):  
Olena P. Bilous ◽  
Agata Z. Wojtal ◽  
Natalia O. Ivanova ◽  
Petro M. Tsarenko ◽  
Olga V. Burova ◽  
...  

The Sasyk Reservoir is one of the largest seaside reservoirs in Ukraine, artificially maintained as a freshwater area including various floodplain areas. The Reservoir originated from an estuary to now being an almost freshwater reservoir. The diatoms (Bacillariophyta) in benthos were investigated for analyzing the coastal zone diversity of the Black Sea inside the borders of Ukraine. The indicated diatom composition was formed by 97 species (100 infraspecies taxa). Some rare marine and freshwater taxa were noted, as well as three species reported in Ukrainian territory for the first time (Navicula vandamii Schoeman et R.E.M. Archibald, Sellaphora difficillima (Hustedt) C.E. Wetzel, L. Ector et D.G. Mann, and Mastogloia laterostrata Hustedt). The bioindicative characteristics of the diatom composition testified to the freshwater condition of the reservoir. Changes to the salinity level of the Sasyk Reservoir were exposed due to the composition of benthic diatoms. The presence of mesohalobous species (7 taxa) acknowledges conditions that are typical for estuaries and mouths of rivers and reveals the salinity changes in the Sasyk Reservoir. Likewise, the prevailing number of oligohalobous diatoms (61 taxa) reveal presence of freshwater in the reservoir. The implementation of the Polish phytobenthos lake assessment method for the nearby Ukrainian Reservoir was conducted for the first time. The multimetric Diatom Index for lake values varied from 0.39 to 0.76, and revealed alterations in the status over the Sasyk sites, ranging from good, moderate, to poor. Thus, it may be concluded that the current ecological status relating to the composition of benthic diatoms of the reservoir located in the coastal zone of the Black Sea is evaluated as having a moderate status class with some exceptions.


Parasitology ◽  
1974 ◽  
Vol 68 (2) ◽  
pp. 155-159 ◽  
Author(s):  
Edward Suchart Upatham

The effects of cercarial concentration and length of exposure on the infection of mice by St Lucian Schistosoma mansoni cercariae were investigated in a running-water habitat.For all exposure times, mice exposed to cercarial concentrations from 2·5 to 40 cercariae per mouse acquired no infections. At higher concentrations, infection rates and worm burdens of mice increased in direct proportion to cercarial concentrations and exposure times. The highest infection rate (57·9 %) and worm burden (46 worms) were obtained in mice exposed for 256 mm to 1280 cercariae per mouse.Cercarial concentrations are low in St Lucian running waters, a fact suggesting that the risk of persons becoming infected while fording, collecting domestic water, washing clothes and swimming in habitats with reasonable flows is very low. It appears that most infected individuals acquire a low worm burden over a rather long period of time.


2019 ◽  
Vol 48 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Anna Budka

Abstract The presented research focused on macrophytes, which constitute a primary element in the assessment of the ecological status of surface waters following the guidelines of the Water Framework Directive. In Poland, such assessments are conducted using the Macrophyte Index for Rivers (MIR). The objective of this study was to characterize macrophyte species in rivers in terms of their information value in the assessment of the ecological status of rivers. The macrophyte survey was carried out at 100 river sites in the lowland area of Poland. Botanical data were used to verify the completeness of samples (the number of taxa). In the presented research, the information provided by each species was controlled. Entropy was used as the main part of information analysis. This analysis showed that the adoption of a standard approach in the studies of river macrophytes is likely to provide sample underestimation (with missing species). This may potentially lead to incorrect determination of MIR and thus result in a wrong environmental decision. On this basis, a sample completeness criterion was developed. Using this criterion, the average value of information for macrophyte species in medium-sized lowland rivers is suffcient to be considered representative.


2002 ◽  
Vol 29 (2) ◽  
pp. 134-153 ◽  
Author(s):  
Björn Malmqvist ◽  
Simon Rundle

Running waters are perhaps the most impacted ecosystem on the planet as they have been the focus for human settlement and are heavily exploited for water supplies, irrigation, electricity generation, and waste disposal. Lotic systems also have an intimate contact with their catchments and so land-use alterations affect them directly. Here long-term trends in the factors that currently impact running waters are reviewed with the aim of predicting what the main threats to rivers will be in the year 2025. The main ultimate factors forcing change in running waters (ecosystem destruction, physical habitat and water chemistry alteration, and the direct addition or removal of species) stem from proximate influences from urbanization, industry, land-use change and water-course alterations. Any one river is likely to be subjected to several types of impact, and the management of impacts on lotic systems is complicated by numerous links between different forms of anthropogenic effect. Long-term trends for different impacts vary. Concentrations of chemical pollutants such as toxins and nutrients have increased in rivers in developed countries over the past century, with recent reductions for some pollutants (e.g. metals, organic toxicants, acidification), and continued increases in others (e.g. nutrients); there are no long-term chemical data for developing countries. Dam construction increased rapidly during the twentieth century, peaking in the 1970s, and the number of reservoirs has stabilized since this time, whereas the transfer of exotic species between lotic systems continues to increase. Hence, there have been some success stories in the attempts to reduce the impacts from anthropogenic impacts in developed nations. Improvements in the pH status of running waters should continue with lower sulphurous emissions, although emissions of nitrous oxides are set to continue under current legislation and will continue to contribute to acidification and nutrient loadings. Climate change also will impact running waters through alterations in hydrology and thermal regimes, although precise predictions are problematic; effects are likely to vary between regions and to operate alongside rather than override those from other impacts. Effects from climate change may be more extreme over longer time scales (>50 years). The overriding pressure on running water ecosystems up to 2025 will stem from the predicted increase in the human population, with concomitant increases in urban development, industry, agricultural activities and water abstraction, diversion and damming. Future degradation could be substantial and rapid (c. 10 years) and will be concentrated in those areas of the world where resources for conservation are most limited and knowledge of lotic ecosystems most incomplete; damage will centre on lowland rivers, which are also relatively poorly studied. Changes in management practices and public awareness do appear to be benefiting running water ecosystems in developed countries, and could underpin conservation strategies in developing countries if they were implemented in a relevant way.


2011 ◽  
Vol 383-390 ◽  
pp. 5321-5326
Author(s):  
Chun Yu Yu ◽  
Kai Li Zhang ◽  
De Zhong Ma ◽  
Zhen Zhou

With regard to the problem that only single index has been used in assessment of reliability, a suitable comprehensive assessment method about reliability index of electromagnetic flowmeter was established, and Mean Time To First Failure(MTTFF), Mean Time Between Failure(MTBF) and equivalent failure rate(D) were selected as the standards of reliability evaluation for the electromagnetic flowmeter in this paper. Because many evaluation elements involved and failure information and evaluation indexes are fuzzy, fuzzy comprehensive evaluation based on entropy weight was introduced to quantify the qualitative evaluation indexes, and indexes weight were determined scientifically by using comprehensive evaluation obtained from combining a subjective expert’s evaluation weight with objective entropy weight. Two kinds of the domestically produced electromagnetic flowmeter were studied, the censored data obtained from the process of consumers’s use were analyzed, and fuzzy comprehensive evaluation method based on entropy weight was used to evaluate the indexes of reliability in two kinds of electromagnetic flowmeter comprehensively. The results show that the conclusion is consistent with the fact, the method can effectively solve the problem existed in current modeling, and evaluation of electromagnetic flowmeter reliability has great practical value in the application.


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