Groundwater is a hidden global keystone ecosystem.

Groundwater is a vital ecosystem of the global water cycle, hosting unique biodiversity and providing essential services to societies. Despite being the largest unfrozen freshwater resource, in a period of depletion by extraction and pollution, groundwater environments have been repeatedly overlooked in global biodiversity conservation agendas. Disregarding the importance of groundwater as an ecosystem ignores its critical role in preserving surface biomes.

New species of Elaphoidella Chappuis, 1929 and Schizopera Sars, 1905 (Copepoda: Harpacticoida) from two caves in northeastern and southern Thailand.

Two new copepod species from two caves in northeastern and southern Thailand are described. Elaphoidella isana sp. nov.

Modelling the effects of multiple stressors on respiration and microbial biomass in the hyporheic zone using decision trees.

Integrity of freshwater surface- and groundwater ecosystems and their ecological and qualitative status greatly depends on ecological processes taking place in streambed sediments overgrown by biofilm, in the hyporheic zone (HZ). Little is known about the interactions and effects of multiple stressors on biologically driven processes in the HZ. In this study, machine learning (ML) tools were used to provide evidence-based information on how stressors and ecologically important environmental factors interact and drive ecological processes and microbial biomass.

A new blind groundwater-dwelling genus of the Cladocera (Crustacea: Branchiopoda) from the Korean Peninsula.

Groundwater-dwelling Cladocera are to date known only from the caves and hyporheic zones of the rivers in Europe (Belgium, England, France, Bosnia and Herzegovina, Macedonia, Slovenia, Spain), Turkey (European part) and Arabian Peninsula (Yemen). All these animals belong to the subfamily Aloninae Dybowski & Grochowski of the family Chydoridae Dybowski & Grochowski (Cladocera: Anomopoda). Examination of some samples collected by our colleagues - experts in Copepoda, Bathynellidae and Amphipoda-in South Korea led us to discovery of a new stygobiotic alonine genus, which is also the first record of a groundwater-dwelling cladoceran in Asia.

Amended diagnosis of the genus (Copepoda, Calanoida), based on redescription of and description of a new species from caves in central Vietnam.

Nannodiaptomus phongnhaensis Dang & Ho, 2001, an endemic stygobiotic diaptomid from Vietnam and the type species of the genus Nannodiaptomus Dang & Ho, 2001, is redescribed on the basis of a new material from its type locality: Hang Phong Nha Cave, Quang Binh province, central Vietnam. We also designated a neotype, because the type material has been lost. The diagnosis of the genus is amended, based on the description of the neotype.

Two new stygobiotic copepod species from the Tibesti area (Northern Chad) and a re-description of Pilocamptus schroederi (van Douwe, 1915).

Between 4th and 18th March 2014, an international group of biologists carried out a hydrobiological expedition to the Ounianga-Tibesti area of northern Chad (Africa). The Tibesti is a desert volcanic area, intersected by the beds of ancient rivers which were active in the Tertiary. In deep canyons there are small water bodies (gueltas/aguelmans), fed by rain and spring water.

Effects of increased temperature on metabolic activity and oxidative stress in the first life stages of marble trout (Salmo marmoratus).

Climate change may result in future alterations in thermal regime which could markedly affect the early developmental stages of cold water fish due to their expected high sensitivity to increasing temperature. In the present study, the effect of temperature increase of 2, 4 and 6°C on the oxygen consumption rate (R), the activity of respiratory electron transport system (ETS) and oxidative stress have been studied in four developmental stages of the marble trout (Salmo marmoratus)-eyed eggs, yolk-sac larvae and juveniles of 1 and 3 months. Oxygen consumption rate and ETS activity increased with level of development and with temperature in all four stages.

Two new stygobiotic species of Elaphoidella (Crustacea: Copepoda: Harpacticoida) with comments on geographical distribution and ecology of harpacticoids from caves in Thailand.

Elaphoidella thailandensis sp. nov. and E.

Groundwater drift as a tracer for identifying sources of spring discharge.

Groundwater invertebrate drift, collected from the spring outlets at the interface of vadose and phreatic zones, has been examined for its potential for identifying sources of discharge from a karst aquifer. Concurrently, major ion geochemistry, dissolved inorganic carbon (δ13CDIC), particulate organic carbon (δ13CPOC), and naturally occurring stable isotopes of oxygen and tritium (δ18O, 3H) were investigated over a period of 1 year in two outlets, a temporary (TS) and a perennial (PS) spring. A few differences in major ion geochemistry and stable isotope composition were found between the two springs together with moderate seasonal variability.

The thermal tolerance of crayfish could be estimated from respiratory electron transport system activity.

Whether electron transport system (ETS) activity could be used as an estimator of crayfish thermal tolerance has been investigated experimentally. Food consumption rate, respiration rates in the air and water, the difference between energy consumption and respiration costs at a given temperature ('potential growth scope', PGS), and ETS activity of Orconectes limosus and Pacifastacus leniusculus were determined over a temperature range of 5-30°C. All concerned parameters were found to be temperature dependent.

A new method for early assessment of effects of exposing two non-target crustacean species, Asellus aquaticus and Gammarus fossarum, to pesticides, a laboratory study.

A reliable method is needed for assessing the condition of aquatic animals and their resistance to toxic pollutants. The physiological responses of two freshwater crustaceans, Asellus aquaticus and Gammarus fossarum, following in vitro exposure to two pesticides (atrazine and imidacloprid), were measured by a combination of electron transport system (ETS) activity and respiration (R). Short-term exposure concentrations were selected according to standard toxicity tests and ranged from 0.

Effects of exposing two non-target crustacean species, Asellus aquaticus L., and Gammarus fossarum Koch., to atrazine and imidacloprid.

The physiological responses of two freshwater crustaceans, Asellus aquaticus L. and Gammarus fossarum Koch., following in vitro exposure to two pesticides were measured.

Black carbon in Slovenian alpine lacustrine sediments.

Black carbon (BC) contents were measured in recent sediments in five high altitude remote alpine lakes, i.e. Lake Krisko Sup.