Flooding and Aquatic Ecosystems

2000 ◽  
pp. 238-268
Author(s):  
Richard S. Wydoski ◽  
Edmund J. Wick
Keyword(s):  
2021 ◽  
Vol 26 (1) ◽  
pp. 2269-2274
Author(s):  
IOAN PĂCEŞILĂ ◽  
EMILIA RADU

Phosphorus is one of the most important inorganic nutrients in aquatic ecosystems, the development and functioning of the phytoplankton communities being often correlated with the degree of availability in assimilable forms of this element. Alkaline phosphatase (AP) is an extracellular enzyme with nonspecific activity that catalyses the hydrolysis of a large variety of organic phosphate esters and release orthophosphates. During 2011-2013, AP Activity (APA) was assessed in the water column and sediments of several aquatic ecosystems from Danube Delta: Roșu Lake, Mândra Lake and their adjacent channels – Roșu-Împuțita and Roșu-Puiu. The intensity of APA widely fluctuated, ranging between 230-2578 nmol p-nitrophenol L-1h-1 in the water column and 2104-15631 nmol p-nitrophenol g-1h-1 in sediment. Along the entire period of the study, APA was the most intense in Roșu-Împuțita channel, for both water and sediment samples. Temporal dynamics revealed its highest values in summer for the water column and in autumn for sediment. Statistical analysis showed significant seasonal diferences of the APA dynamics in spring vs. summer and autumn for the water column, and any relevant diferences for sediment.


2019 ◽  
Vol 70 (11) ◽  
pp. 3903-3907
Author(s):  
Galina Marusic ◽  
Valeriu Panaitescu

The paper deals with the issues related to the pollution of aquatic ecosystems. The influence of turbulence on the transport and dispersion of pollutants in the mentioned systems, as well as the calculation of the turbulent diffusion coefficients are studied. A case study on the determination of turbulent diffusion coefficients for some sectors of the Prut River is presented. A new method is proposed for the determination of the turbulent diffusion coefficients in the pollutant transport equation for specific sectors of a river, according to the associated number of P�clet, calculated for each specific area: the left bank, the right bank and the middle of the river.


2015 ◽  
Vol 4 (0) ◽  
pp. 9781780403007-9781780403007 ◽  
Author(s):  
M. Gladyshev

2008 ◽  
Vol 3 (2) ◽  
Author(s):  
L. Sala ◽  
S. Romero de Tejada

Where there is water scarcity, the situation is dramatic for aquatic ecosystems. In many Mediterranean basins the exploitation of water resources has gone clearly beyond renewable level and affects aquatic ecosystems. Thus, they may benefit from the recycling of high-quality effluents that can be used to cope with environmental water demands instead of being discharged. Their reclamation with natural technologies produces an improvement in quality based on the development of trophic webs built upon nutrients still dissolved in the reclaimed water. The main project in the Costa Brava area is that of the Empuriabrava constructed wetland system, where nitrified effluent is further treated to reduce the concentration of nutrients in the water and is reused for environmental enhancement. This facility is also an interesting site for bird-watching. Other projects where water recycling produces indirect benefits on the aquatic ecosystems are those in Tossa de Mar, affecting the “temporary” Tossa Creek (a watercourse which flows on temporary basis according to rainfall patterns), and in the Aro Valley, affecting the also “temporary”, but slightly bigger, Ridaura River. This document summarizes these projects and proposes practical recommendations for the use of treated effluents in the recreation and restoration of aquatic ecosystems.


Sign in / Sign up

Export Citation Format

Share Document