Vízügyi Közlemények, 2001 (83. évfolyam)

2. füzet - Rövidebb tanulmányok, közlemények, beszámolók

Gondolatok a vízminőségi célállapot és termelhetöség meghatározásáról 333 — For some parameters, which do not have simultaneous internal sinks and sources and the variation of which can be described by one of these in a lumped way, one could use simple first order reaction kinetics, describing the longitudinal changes of this parameter (or the relevant mass fluxes of it). This method might yield a rough approximation of the "allowable load". Nevertheless, this method must not be considered on the long term and for the wide range of parameters, the basic of calculating the "allowable loads". Since the present extremely poor (practically non-existent) Hungarian emission data base consists mostly of a single generally available parameter, the COD. therefore this most simple modelling method could be applied for this parameter, with serious reservations. - The allowable plant-nutrient load of lakes can be relatively reliably determined using a simple (fully mixed reactor type) lake model. For the use of this model the nutrient retention rate of a given lake must be estimated on the basis of the measurement data of inputs, lake-nutrients and outputs. Nevertheless the problem of reducing nutrient loads is not an easy one and is usually dominated by the control of non-point sources. However, the reliable calculation (modelling) methods of non-point source loads arc still missing (also at global scale). Further on it was stated that the carrying out of a nation-wide programme for the determination of WQ target conditions and of the corresponding allowable loads would be hindered by two basic problems: 1. For many parameters the bulk of the pollution load of our streams originates from abroad and thus the control of its sources is mostly outside the competence of the relevant Hungarian authorities, for all transboundary streams. 2. For many parameters the bulk of the pollution load originates from non-point (or unidentified) sources of pollution. The consideration of these sources is hindered by a severe lack of data (inside and outside of Hungary). Finally, as the result of this not-at-all "rosy" picture outlined above, the authors wished to express their hope, that this study will draw the attention of all relevant Hungarian (and in the case of a foreseen English publication the foreign, international) authorities (stakeholders, decision makers) to the likely difficulties of professionally acceptable (and cost efficient) water quality management. It is also hoped, that the recognition of these circumstances will result in a basic break-through in the basic principles. This break-through shall be manifested primarily in transforming scientific results into the practice and thus in the carrying out of the relevant measurement and experimental tasks, involving also the task-oriented development of the routine monitoring systems. * * * Gedanken zur Bestsimmung des Zielzustandes der Wassergüte und der Belastbarkeit von Dr.-lng. Géza JOLÁN KAI DSc. und Dipl.-Ing. István BÍRÓ Die Verfasser vertreten die Ansicht, daß weder der Zielzustand der Wassergüte, noch die denselben auslösende/beeinflussende Belastbarkeit ohne ein für das gegebene Gewässersystem (sowie dessen Verschmutzungsquellen) aufgestelltes Wassergütemodell ermittelt werden kann. (Einschränkend wird bemerkt, daß der Zielzustand ggf. vielleicht auch ohne Modell bestimmt werden kann, die Belastbarkeit aber keineswegs.) Obige Feststellung ist die Folge der Tatsache, daß die den Gütezustand der Rezipienten determinierende Belastbarkeit einzig und allein über eine numerische Erfassung der Beziehungen zwischen Ursache und Folge bestimmt werden kann. Dabei ist hier die Ursache die Ver-