Green Roof Envrionment Biochar

Due to the drought prone environment of green roofs moisture is key in determining plant growth.

Green roof envrionment biochar.

Extensive pre grown green roofs are a source of nutrient pollution. Biochar is a solid carbon material produced from organic material. A short term laboratory test with green roofs receiving artificial rainfall showed that the addition of biochar could be an option to decrease nutrient discharge and also to improve water retention of green roofs beck et al 2011. Another biochar type increased the leaching of nutrients from green roofs.

Green roof growing media need to be designed to insure low concentrations of nutrients in storm water runoff. Given the need to keep the per sq foot weight of the green roof installation low our biochar is ideal due to the fact that it is a very light media yet has a very great whc lessing water and irrigation. Chen h 1 ma j 2 wei j 3 gong x 3 yu x 4 guo h 5 zhao y 6. Biochar s ability to bind nutrients reduces the risk of nutrients being washed away with the runoff water.

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. It is similar to charcoal in its composition but it s used as a soil amendment not fuel. Addition of biochar reduces total organic carbon content in runoff by 67 72. Experimental green roofs a comparison of standard and green roof layers with a combination of biochar article pdf available january 2020 with 112 reads how we measure reads.

Biochar increases plant growth and alters microbial communities via regulating the moisture and temperature of green roof substrates. Biochar is highly porous lightweight and long lasting. Biochar addition to green roof substrates has also been shown to delay the onset of wilting by plants due to increased water holding capacity thereby enhancing plant survival cao et al 2014. Structurally green roofs are comprised of native vegetation planting medium soil less filter fabric drainage storage layer insulation waterproof membrane protection board and roof deck.

Biochar in green roof soil reduces nitrogen and phosphorus in the runoff. The effects of biochar on green roof plant and soil microorganism. Adding biochar increased water holding capacity whc and plant available water paw which postponed the days to permanent wilting point dpw. Biochar is a product that shows promise in addressing issues of green roof weight and runoff.

Incorporating biochar into green roof design. Biochar improves water retention of saturated soil. Addition of biochar reduces turbidity of runoff.