Green Roof Envrionment Biochar

The effects of biochar on green roof plant and soil microorganism.

Green roof envrionment biochar.

A green roof platform experiment hereafter experiment testing the impacts of biochar on green roof runoff quality and water retention was established in the city of lahti southern finland latitude 6 756 000 longitude 4 24 000 in early july 2013. Biochar amended in the substrate reduced cumulative nutrient leaching. Given the need to keep the per sq foot weight of the. Adding biochar increased water holding capacity whc and plant available water paw which postponed the days to permanent wilting point dpw.

Due to the drought prone environment of green roofs moisture is key in determining plant growth. Biochar is rapidly replacing perlite as the medium of choice for green roofs and biochar supreme s environmental ultra tm is an ideal soil less component to green roof installations particularly for its characteristics of high surface area high activity porosity and very light weight. Stovin 71 documented that green roofs have considerable potential for rainwater source control with a water retention capacity of 34. The biochar used in this study was a 300 series blend from international tech corporation.

The laboratory experiment was established on 20 march. Pro gro extensive mix is a proprietary blend specially designed as a green roof growing media that contains a mix of gravel sand silt clay buccola 2008 as well as specially screened pumice fiber life compost and paper fiber. The difference between the carbon content of the sludge green roof and of the biochar green roof was 18 8 30 5 and the greatest dif ference was ob served for the 10 treatments figure 4a. To test whether the quality of biochar has an effect on its performance a 6 week long laboratory experiment with two different biochar products were tested as a layer in the substrate of sedum mats that were cut from pre grown vegetation mats produced in sweden product name nordic green roof sedum matte delivered by eg trading ltd.

38 and cao et al. Biochar s ability to bind nutrients reduces the risk of nutrients being washed away with the runoff water. 72 applied biochar into. The quality of the water that leaves green roofs rain beds and other plantings is thereby increased and the risk of polluting lakes seas and other watercourses is reduced.

Biochar had a combined impact on runoff quantity and quality over time.