A green roof segment for monitoring the hydrological and thermal behaviour of anthropogenic soil systems

Abstract

Jelínková V., Dohnal M., Picek T. (2015): A green roof segment for monitoring the hydrological and thermal behaviour of anthropogenic soil systems. Soil & Water Res., 10: 262-270.Green roofs and similar anthropogenic soil-plant systems in conurbations have a high relevance for society, especially in a changing climate. Understanding the hydrological performance of green roof substrates is a significant task in the framework of sustainable urban planning and water/energy management in urban areas. Potential retention and detention capabilities of anthropogenic, light weight, highly permeable soil systems and their continued performance over time are of major importance. A green roof test segment was designed to investigate the benefits of such anthropogenic systems. This adaptable low-cost system allows for long-term monitoring of preferred characteristics. Temperature and water balance measurements complemented with meteorological observations and studies of physical properties of substrates provide a basis for a detailed analysis of thermal and hydrological regime in green roof systems. The very first results obtained from the test segment have confirmed the green roof systems benefits. Reduced temperature fluctuations as well as rainfall runoff were attained compared to the traditional roof systems. Depending on numerous factors including the substrate material or vegetation cover, in the green roof tested the temperature amplitude for a selected period of nonfreezing days (with minimum ambient air temperature of 2.8°C) was suppressed by about 6.5°C on average. The ability to completely prevent (light rainfall events) or reduce and delay (medium and heavy rainfall events) the peak runoff was demonstrated, too.

Identification of soil-cooling rains in southern France from soil temperature and soil moisture observations

“…Since severe convective events associated with the intense soil-cooling events observed in this study tend to become more and more frequent in relation to climate change (Feng et al, 2016), soil-cooling effects may play a role in the response of the Earth system to climate change. Moreover, rainwater temperature estimates from observation networks or from atmospheric model simulations could be beneficial for a number of applications such as urban heat island monitoring (e.g., Jelinkova et al, 2015), drinking water quality monitoring (e.g., Chubaka et al, 2018), the estimation of the emission rates of greenhouse gases by soils (e.g., Gagnon et al, 2018), or the quantification of soil erosion (e.g., Sachs and Sarah, 2017).…”

“…In both studies, it was assumed that rainwater temperature was equal to the air wet-bulb temper-S. Zhang et al: Identification of soil-cooling rains in southern France ature. This assumption is valid for raindrops in thermal equilibrium with the ambient air (Kinzer and Gunn, 1951). Both studies tended to show a soil-cooling effect over France, but for some regions at higher latitudes a soil-warming effect was simulated.…”

Identification of soil-cooling rains in southern France from soil temperature and soil moisture observations

“…Moreover, rainwater temperature estimates from observation networks or from atmospheric model simulations could be beneficial for a number of applications such as urban heat island monitoring (e.g. Jelinkova et al, 2015), drink-water quality monitoring (e.g. Chubaka et al, 2018), the estimation of the emission rates of greenhouse gases by soils (e.g.…”

Hydrological and thermal regime of a thin green roof system evaluated by physically-based model

“…The green infrastructure facilities of the University Centre for Energy Efficient Buildings (CTU in Prague) serve as a basis for studying heat load and stormwater reduction in lightweight green-roof systems. Jelinkova et al (2015) designed simple and durable test beds equipped for automatic continuous monitoring, suitable for long-term testing of different green-roof systems. Jelinkova et al (2016) studied the thermal and water regime of two green roof assemblies with different soil mixtures during the first months of their life cycle.…”