Iwona Wagner

Effect of hydrological patterns of tributaries on biotic processes in a lowland reservoir - consequences for restoration.

Relationships between river hydrology and chemistry were considered as the key point of ecohydrological approach for a shallow, eutrophic reservoir (2500 ha) restoration. By comparison of data from the two main tributaries of the reservoir it was demonstrated that nutrient concentrations and consequently load supplying the reservoir are significantly positively correlated with hydrological characteristics of the spring spate of the rivers and depends on theirs catchment characteristics. Concentrations of total phosphorus (TP), which is the main factor responsible for reservoir eutrophication, are positively correlated with spring spate dynamics (Pilica River, r=0.619; P=0.05; Luciaza River, r=0.443; P=0.05) but not with discharge. The above findings also indicate that a high nutrient load has been entering the reservoir in relatively small water volume. As biota react with the nutrient load, a statistically significant correlation was found (r=0.769; P<0.05) between hydrological characteristics of the tributaries’ spring spates and biomass of diatoms in the reservoir. The understanding of temporal variability of nutrient supply in relation to the hydrology of tributaries indicates that a fundamental first step of reservoir restoration should be the reduction of the external nutrient load transported into the reservoir by rivers at the raising hydrograph limb. This may be achieved by converting part of the natural river floodplain in the upper part of the reservoir into constructed wetlands. On the basis of the data obtained, maps and area photographs, the necessary area of treatment wetlands has been estimated. For a reduction of 20% of the TP load of an average spring flood, up to 5 km of the Pilica River valley has to be converted into constructed wetlands (area, 150 ha; depth, 1 m). However, for a reduction of 25% of the load, a re-construction of up to 25 km (area, 500 ha; depth, 1.5 m) of the river is necessary.

Ecohydrological system solutions to enhance ecosystem services: the Pilica River Demonstration Project

Abstract The application of ecohydrology principles as part of Integrated Water Resources Management (IWRM) has the potential to enhance the resilience of a catchment to anthropogenic impacts. Linking this approach with an understanding of water users and social and economic conditions in a given region, provides a foundation for the development of system solutions. Improving the quality of the environment, and the ecosystem services provided, can be a driver of new employment opportunities that contribute to both the overall economy of a region and sustainability. With these goals in mind, the paper presents a four-step approach for implementation of ecohydrology principles in IWRM, including a) monitoring of threats, b) analysis of the cause-effect relationships, c) development of methods, and d) system solutions. This approach was formulated and tested within a UNESCO-IHP and UNEP-IETC Demonstration Project on the Pilica River in Poland. This project aims to support fulfilment of Polands obligations resulting from the EU Water Framework Directive and other European directives, and constitutional obligations for sustainable development. Attempts to transfer lessons learned to other catchments and socio-ecological systems (such as urban catchments) are highlighted.

An ecohydrological approach for the protection and enhancement of ecosystem services

Water is the only factor linking all ecosystem services – provisional, supporting, regulatory, and cultural. For this reason water resources are highly vulnerable to human pressures and become a cause of environmental insecurity in many regions of the world. The methods of coping with water-related problems were built on the conviction that the risk of losing water driven services can be, to a great extent, anticipated and diminished by policy and technical and technological measures. However, considering the number of factors regulating accessibility and quality of water, the risks associated with water scarcity should be considered as having higher damage potential, persistency, ubiquity and irreversibility, especially under increasing climate variability, than previously assumed. Handling risk is problematic also due to high uncertainty and severe outcomes associated with rising water needs, conflicting demands, and low awareness among citizens. Many important issues affecting water management are often rooted in the past, e.g. poverty, dramatic population growth, industrialization, land transformations, inefficient policy and overengineering. Unknown risk, damages difficult to assess, and low capacity for worldwide introduction of top, but expensive technologies led back to questions concerning a potential for using natural mechanisms to maintain ecosystem resilience and to mitigate human activities, which are handicapping. A proposed ecohydrology approach scrutinizes the interrelation between components of river catchments, focusing especially on those between biota and hydrology. It suggests using these relations for increasing an adaptive capacity of ecosystems and thus the stability and security of ecosystem services.

Sequential Sedimentation-Biofiltration System for the purification of a small urban river (the Sokolowka, Lodz) supplied by stormwater

The study analyses the efficiency of a Sequentional Sedimentation-Biofiltration System (SSBS) built on the Sokolowka river in Lodz (Poland). It was constructed to purify a small urban river whose hydrological regime is dominated by stormwater and meltwater. The SSBS was constructed on a limited area as multi-zone constructed wetlands. The SSBS consists of three zones: sedimentation zone with structures added to improve sedimentation, a geochemical barrier made of limestone deposit and biofiltration zone. The purification processes of total suspended solids (TSS), total phosphorus (TP), total nitrogen (TP) and other nutrients: phosphates (PO43-), ammonium (NH4+) and nitrates (NO3-) of the SSBS were analyzed. Chloride (Cl-) reduction was investigated. Monitoring conducted in the first two hydrological years after construction indicated that the SSBS removed 61.4% of TSS, 37.3% of TP, 30.4% of PO43-, 46.1% of TN, 2.8% of NH4+, 44.8% of NO3- and 64.0% of Cl-. The sedimentation zone played a key role in removing TSS and nutrients. The geochemical barrier and biofiltration zone each significantly improved overall efficiency by 4-10% for TSS, PO43-, TN, NO3- and Cl-. Although the system reduced the concentration of chloride, further studies are needed to determine the circulation of Cl- in constructed wetlands (CWs), and to assess its impact on purification processes.

University’s multi-scale initiatives for redefining city development

Purpose The purpose of this paper is to present the varied roles played by the University of Lodz (UL) in maintaining and restoring the natural capital of a city as a driver for sustainable city development. The higher education institution can be perceived as visionary, originator and executor of natural capital projects. Design/methodology/approach The paper analyses three cases performed by the Faculty of Biology and Environmental Protection, UL, in the city of Lodz. The activities are based on different scales ranging from city-wide to local, e.g. river and green infrastructure, and which vary in character from policy planning to implementation. Findings Natural capital projects influence city development on different levels: by the initiation of legal protection, by the implementation of rehabilitation concepts for rivers and by influencing the strategic documents for mid-term and long-term urban development. Originality/value The university has the potential for multidisciplinary engagement in the development of urban sustainability. In large-scale projects, academics play a more conceptual role, in capacity building and knowledge transfer, while in local-scale implementations, their role includes innovation, know-how and technology transfer. Moreover, it may act as a reinforcement hub, by safeguarding and strengthening the natural capital of the city.