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INTERNATIONAL COOPERATION ON WATER SCIENCES AND RESEARCHmanagement of water and nutrient dynamics from the landscapeto aquatic ecosystems, with the ecohydrological aim of enhancingcarrying capacity, must take place through harmonizing traditionalhydroengineering solutions with biotechnology. 7 Due to the complexityof synergetic and mutually interacting hydrological processes, theimplementation of biotechnological solutions to ensure the regulationof catchment-scale water must lead to enhancement of the self-organizationfunction of ecosystem/nutrient dynamics, 8 and must be carriedout using an adaptive assessment and management methodology. 9Recently applied scientific approaches and the methodologiesused in conservation, restoration, ecological engineering and ecohydrologyrepresent progress in understanding the ecological structureand dynamics of ecosystems and the impact of human activities.They embody a move from a species-structure-oriented perspectivetowards a more progressively process-oriented approach, exemplifiedby ecological engineering and ecohydrology. 10The goal of ecohydrology as a problem-solving science is to determinewhy the biosphere is drying and soil fertility is declining, andhow these trends can be reversed. The major challenges are:• slowing the transfer of water from the atmosphere to the sea(prioritizing flood and drought control)• reducing input and regulating the allocation of excess nutrientsand pollutants in aquatic ecosystems to improve water quality,biodiversity and human health• enhancing ecosystem carrying capacity (water resources,biodiversity, ecosystem services for society and resilience) bydual regulation towards harmonization with societal needs.The proposed highly-complex approach must be transferred to society,decision makers and politicians through transdisciplinary education.In the case of the highly-complex environmental problems that weexperience today there is an urgent need to move away from specializationin education and add a knowledge integrating element,enabling a broader understanding of the complexity of environmentalprocesses. Integration of the knowledge garnered across differentdisciplines should be facilitated on the basis of a common methodologicalbackground. Parallel educational efforts are needed to raisethe consciousness of society concerning possible realistic scenariosfor harmonizing societal needs with enhanced ecosystem potential:water, biodiversity, ecosystem services for society and resilience.Reducing cyanobacterial blooms: Sulejów ReservoirModification of the biogeochemical cycles on a catchment scale –resulting from degraded biocenosis structure and increased emissionsof nutrient and pollutants combined with climate change – seemsto be the main reason for acceleration of the eutrophication process,including the presence of cyanobacterial blooms in freshwater andcoastal ecosystems. An important indicator for assessing the threatof cyanobacteria to the environment and humans is the activity oftoxic genotypes, which are responsible for producing cyanotoxins thatcan cause skin irritation, impaired breathing (neurotoxin), diarrhoea,acute gastroenteritis, and kidney and liver damage (hepato- and cytotoxins).11 Thus, the molecular monitoring of toxigenic strains ofcyanobacteria acts as a precise indicator of the possible health threat.The Pilica River in Central Poland is a global reference site forecohydrology under the United Nations Educational, Scientific andCultural Organization International Hydrological Programme. Theriver’s Sulejów Reservoir is a dam reservoir with progressive anthropogeniceutrophication, in which cyanobacterial blooms appearevery year. 12 During the bloom accumulation, the totalmicrocystin (cyanobacterial hepatotoxin) concentrationin the water could increase up to 30 μg L -1 . 13 Studiesusing sensitive molecular methods based on the detectionof genes involved in the synthesis of microcystinshowed that the genotypes of microcystin-producingcyanobacteria occurred throughout the period of monitoring,and their number increased with deterioratingenvironmental conditions for the development of cyanobacteria.14 This demonstrates that the availability ofphosphorus is a driving factor determining the intensityof cyanobacterial blooms in the reservoir. 15 Phosphorusconcentration (annual average: 0.078- 0.215 mg TP/l)strongly depends on the discharge pattern of the maintributaries and the chemical composition of the river’swater, which both determine the nutrient load enteringthe reservoir (average 87-693 t TP/year).The reduction of nutrient fluxes from the catchment isa fundamental measure for reducing toxic blooms. Due tovarious cumulative impacts from agriculture, urban zonesand recreation, actions aimed at reducing the developmentof cyanobacterial blooms must be based on cooperationbetween scientists, decision makers and stakeholders.In order to reverse eutrophication of a reservoir, itswater balance and nutrient flows should be considered inthe context of a whole catchment basin. The MONERISmodel for the Pilica River Basin showed that only around6.5 per cent of the phosphorus loads were from pointsources, with around 18.4 per cent from urban areas.Three quarters of the phosphorus load came from thelandscape, mainly associated with soil particles andorganic material eroded during flow events.Reducing the nutrient loads coming from the landscapedue to a high complexity of water-soil-plant-society interactionshas been much more complicated than controllingthe loads originating from the point sources. The preservationor construction of riparian land/water buffer zones(ecotones) is widely recommended to reduce the impactof nutrients present in the landscape on freshwater ecosystems.These linear belts of permanent vegetation adjacentto an aquatic ecosystem permit the improvement of waterquality by trapping and removing various non-pointsource pollutants from both overland and shallow subsurfaceflow pathways. Phosphorus retention in ecotones iscontrolled by a range of physical, geochemical and biologicalprocesses, including sediment deposition, adsorptionto iron and aluminium oxides or precipitation of calciumphosphates, and plant uptake.Highly effective buffer zones were designed and implementedin the direct catchment of the Sulejów Reservoir,an area characterized by heavy groundwater pollution,with phosphorus arising from non-point source pollutionfrom illegally leaking septic tanks. This demo site ofthe LIFE+EKOROB project 16 is located in a recreationalarea, where the shoreline is surrounded by cottages. Theseepage of groundwater heavily contaminated with phosphoruswas observed below the water level in the reservoirshoreline. Average phosphate concentration in groundwaterreached 3.1 mg PO 4/l, exceeding the threshold value[ 300 ]