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Urban stream assessment procedure: An integrative framework for assessing stream condition in the urban environment
Published in Wim Uijttewaal, Mário J. Franca, Daniel Valero, Victor Chavarrias, Clàudia Ylla Arbós, Ralph Schielen, Alessandra Crosato, River Flow 2020, 2020
Much of the information on urban streams is related to the hydrological, biological, and chemical assessments and the associated effects of watershed urbanization such as changes to the hydrologic regime and water quality (Beck et al. 2019). Most assessments are limited to measurements of simplified parameters (such as hydrology and water quality) within individual reaches (Francis 2014, Booth and Fischenich 2015) and modeled characteristics of hydraulic and geomorphology indicators (Hawley et al. 2013, Mazor et al. 2018). To date, hydromorphological assessment methods have often focused upon the occurrence and spatial configuration of the channel (Gregory 2006) or physical habitats at the reach or segment scale (Davenport and Gurnell 2004), placing little emphasis on streams in the urban environment and their complex system dynamics including “pressure” or “response” variables. The application of a hydromorphological framework approach such as that described in this paper seeks to overcome this problem.
Hydrology: Urban
Published in Yeqiao Wang, Fresh Water and Watersheds, 2020
Stormflows in urban streams also increase in frequency. In natural basins, when soils are dry, rainfall events are absorbed by the soils and streams respond very little. In most of the humid United States, natural streams experience very few large flows in late summer and early fall when soils are dry. Impervious surfaces provide no such buffering and produce stormflows during all rainfall events regardless of soil moisture conditions. Cumulative hydrologic alterations of an urban basin can also dramatically affect wetland hydropatterns (the time series of water levels), causing shifts in the composition of vegetative and amphibian communities. Urbanization reduces recharge rates over much of the landscape, thus reducing local sources of stream baseflow; but urban areas often import water from other basins, and groundwater and baseflows in urban streams may be supplemented by leakage from the water and sewage distribution system, lawn watering, and car washing. Thus, different studies have found both increases and decreases in base- flows as a result of urbanization.
Floods in Greece
Published in Zbigniew W. Kundzewicz, Changes in Flood Risk in Europe, 2019
D. Koutsoyiannis, N. Mamassis, A. Efstratiadis, N. Zarkadoulas, I. Markonis
Palaeoflood data, mythological narrations, written documents and archaeological evidence suggest that floods have created severe problems to humans at all stages of civilization, and also that river flood regimes have changed continually. Such changes reflect the perpetual change of climate but are also influenced, in a positive or negative manner, by human interventions for land use and the human struggle to control river flows. Evidently, such interventions have been magnified in recent decades. However, despite technological progress, the example of Greece, where civilization has flourished for millennia, suggests that the problems with respect to floods are more severe today than they were in ancient times. Above all, urbanization has amplified the problems and has resulted in degradation of urban streams. Restoration, maintenance and water quality control of urban streams, along with source control and flood retention, constitute big challenges for modern societies. In modified rivers, a balance of flood control measures and environmental conservation practices, with particular emphasis on aquatic ecosystems is strongly needed.
Physical and hydraulic properties of bioretention substrate using hexadecyl trimethyl ammonium bromide (HDTMA) modified zeolite
Published in Environmental Technology, 2022
Yifeng Qin, Mingsheng Chen, Yunqing Fang, Xudong Li, Jin Wang, Jiangping Qiu
Rapid urbanisation process has adverse effects on urban hydrology, including increased runoff magnitude and frequency, decreased infiltration and underground water recharge, which would cause ecological degradation of urban streams and negative impact on the urban ecosystem [1–4]. Moreover, with the increased runoff from the urban area, more pollutants such as organic and inorganic matters, heavy metal, and pharmaceutical compounds would be scoured into urban streams, which would cause deterioration of water quality and threaten human health [3, 5–7]. To address these issues, integrated water management approaches such as low impact development (LID), water sensitive urban design (WSUD), and best management practices (BMPs) have been adopted as response to the urban hydrology problems [8–10]. Bioretention has been recognised as an effective stormwater management practice that suffices the needs of these approaches. By using soils and other porous materials as the substrate media to promoting infiltration and evapotranspiration of stormwater, bioretention systems bring the hydrological condition closer to the predevelopment status [9,11], and it also improves stormwater quality [12–15].
Influence of stormwater control measures on water quality at nested sites in a small suburban watershed
Published in Urban Water Journal, 2018
Rachel D. Scarlett, Sara K. McMillan, Colin D. Bell, Sandra M. Clinton, Anne J. Jefferson, P. Suresh C. Rao
We also observe a delayed pulse of nutrients from the SCM to the receiving stream during hydrograph recession. This finding implies that hydrologic regimes within SCMs have a significant effect on essential nutrient availability in the stream and likely on stream ecological processes. It is suggested, yet seldom observed, that the redistribution of stormflows to baseflows and control of peak flows through stormwater mitigation can aid in ecological recovery of urban streams by protecting instream ecosystems from disturbances such as scour (Palmer, Hondula, and Koch 2014; Konrad and Booth 2005). We show that hydrologic regimes also alter nutrient availability in the stream during low flow periods, which may be a key limitation to or aid in mediating ecological recovery after a hydrologic disturbance.
How historical land use/land cover changes affected ecosystem services in lake Pamvotis, Greece
Published in Human and Ecological Risk Assessment: An International Journal, 2021
Dionissis Latinopoulos, Maria Koulouri, Ifigenia Kagalou
A quite fragmented landscape was revealed by the LULC maps, where designated areas per use surround the lake. Starting from the city in reverse clockwise order, urban areas are followed by agricultural and then some seminatural take the lead due to the hilly terrain and the slopes. Each LULC affects the lake’s system in a different way. In Lake Pamvotis, more than 25% of the riparian habitat zone is covered by urban areas and a similar proportion by agricultural lands. Urban development affects greatly freshwater ecosystems and related services (Wangai et al. 2019) provoking the “urban stream syndrome” (Booth et al. 2016). Roads and impervious areas creation are long recognized as a potential factor of sedimentation increase (Waters 1995). Such a rapid urbanization has detrimental impacts on ecology and environment and has become a major concern in many countries, both developing and developed (Tan et al. 2016). Moreover, besides many urban works target flood protection, the latest has negative correlation with such large LULC changes in the riparian habitat buffer zone due to augmented vulnerability (Olokeogun et al. 2020). Agricultural expansion at the expense of natural and seminatural areas d affects the adjacent freshwaters. Agricultural production used to and still plays a central role in the environmental and socio-economic dynamics of the area speeding the eutrophication process (Drinan et al. 2013). Peppa et al. (2020) through a satellite assessment confirmed Pamvotis Lake is a eutrophic one and found that for the years 2016–2018 the highest chl-a concentration was in the east and south-east of the lake. This is the area hosting the majority of agricultural land and the most affected by wash-off (Kagalou et al. 2001).