The scarcity of water can result in a direct conflict between the protection of aquatic resources and water use. For many agencies, environmental flow (EF) methods are essential in environmental impact assessments and in the protection of important fisheries resources. The objective of this paper is to compare selected hydrological and hydraulic methods and determine the scientifically acceptable and cost-effective way to environmental flow within a section of a mountain river with high naturalness, on the example of the Wisłoka. In this paper, environmental flow was calculated using conventional hydrological methods: Tennant’s, Tessman’s, flow duration curve and hydraulic methods, wetted perimeter method (WPM) and method based directly on ichthyofauna habitat requirements (spawn and migration). The novelty is the combined use of the hydraulic and hydrological methods which relates to flow hydraulics based directly on ichthyofauna habitat conditions. The hydraulic methods provide lower values of environmental flow in comparison with the hydrological methods. The key issue in the use of the hydraulic methods is the choice of criteria. The development of the required set of parameters while taking into account their seasonal nature shifts the method toward habitat modeling methods. However, the scope of habitat requirements of ecosystems must be defined, including the set of aquatic organisms and watercourse type before a hydraulic method may be widely used. Being generally low-cost and simple, the methods presented in this paper can be applied in the water management legislative process.
This work was aimed at comparing the instream flow environment of four basic hydromorphological units of a mountain gravel-bed river: pools, runs, riffles and rapids. A survey was performed during the average flow stage on the Skawa River in southern Poland. In the 3.5 km long reach, 31 physical habitats were surveyed: eight pools, eight runs, nine riffles and seven rapids. Using Micro ADV Sontek equipment, instantaneous velocity time series components were measured at eight locations in three positions—z/h = 0.2, 0.4 and 0.6—in each unit. Turbulence descriptors—the mean components of velocity, turbulence intensities calculated as the root mean square of velocity component time series, turbulent kinetic energy TKE, Reynolds shear stresses and standard hydraulic attribute, i.e., Froude number—were estimated. Although there was a wide dispersion of the turbulence variable distributions, a standard tendency of decreased mean velocity and increased turbulence towards the bottom was observed. Most turbulence parameters—streamwise velocity, turbulence intensities, TKE and streamwise-vertical Reynolds shear stresses—reveal differences of instream flow environment between the pools, runs and riffles. In addition, the mean turbulence intensities suggested a 1:2:3:3 proportion of turbulence intensity in pools, runs, riffles and rapids, respectively. Riffles and rapids, in general, have similar turbulence values, whereas rapids are deeper and visually more energetic.
Abstract. Flow variability determines the conditions of river ecosystems and river ecological functioning. The variability of ecological processes in river ecosystems gradually decreases due to river channelization and incision. Prediction of the environmental flow allows us to keep biological diversity and river health developed as a response to the degradation of aquatic ecosystems overexploited by humans. The goal of the study was to test the influence of river incision on environmental flow estimation based on the Biological Monitoring Working Party (BMWP) macroinvertebrate index. A total of 240 macroinvertebrate assemblages of 12 waterbodies differing in bed substrate and amplitude of discharge were surveyed in southern Poland. Variations in the distribution of 151 466 macroinvertebrates belonging to 92 families were analysed. The similarity of benthic macroinvertebrates reflects the typological division of the rivers into three classes: Tatra mountain streams, mountain flysch rivers, and upland carbonate and silicate rivers. As a response variable reflecting the macroinvertebrate distribution in the river, the BMWP_PL index was chosen. The river incision significantly increased the values of e-flow calculations in relation to redeposited channels. The area of optimal habitat for macroinvertebrates decreased with the bed incision intensity. In highly incised rivers, the environmental flow values are close to the mean annual flow, suggesting that a high volume of water is needed to obtain good macroinvertebrate conditions. As a consequence, river downcutting processes and impoverishment of optimal habitats will proceed.
WprowadzenieRynek farmaceutyczny jest specyficznym obszarem polskiej gospodarki. Rzπ-dzi siÍ prawami rynkowymi, na ktÛrych kszta≥t wp≥ywajπ zachowania zaleønych od siebie podmiotÛw uczestniczπcych w procesie obrotu lekami oraz przepisy prawna administracyjnego. Dystrybutorzy lekÛw, to gracze rynkowi, ktÛrzy konkurujπc potencja≥em cenowym, wykorzystujπ efekt skali i maksymalizujπ zyski. Z kolei prawodawca, nie w konkurencji upatruje korzyúci dla pacjenta, lecz w obniøeniu cen produktÛw leczniczych i ich dostÍpnoúci.Powaøne zmiany, jakie zachodzπ w przepisach prawa farmaceutycznego, decydujπ o procesie obrotu lekami miÍdzy producentem i nabywcπ. PaÒstwo bÍdπ-ce regulatorem rynku, wp≥ywa z jednej strony na indywidualizacjÍ stosunkÛw wspÛ≥pracy miÍdzy tymi podmiotami w obrocie lekami, z drugiej zaú na ich funkcjonowanie. ImplementacjÍ przepisÛw prawa na gruncie polskim z wymogami prawa unijnego w obrocie lekami tworzy uchwalona 6 wrzeúnia 2001 r. Ustawa Prawo farmaceutyczne (Dz. U. z 2004 r. Nr 53, poz. 533 ze zm.). Zgodnie z niπ, dostÍpne w obrocie leki sπ ujÍte w kategoriach:
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