Engineered (bioretention) media amendments material properties and specifications.
Link to this table
Property | Biochar | Coir</ | Water treatment residuals | Spent lime | Compost | Peat | Iron | Wood chips |
---|---|---|---|---|---|---|---|---|
Phosphorus leaching | No | No to slight | ||||||
Phosphorus retention | No to slight | No | ||||||
Handling concerns | Potential explosive concerns in closed space situations; volatile compounds (depending on pyrolysis temperature) | Dust | ||||||
Soil hydraulic properties | Significant improvement | Significant improvement | ||||||
Soil physical properties | Significant improvement | Moderate improvement | ||||||
Plant effects | Beneficial but varies with feedstock | Beneficial | ||||||
Availability | Multiple distributors | Widely available | ||||||
Specifications available | Limited due to variability with feedstocks | Yes | ||||||
Cost | ||||||||
Research needs | Feedstocks suitable for stormwater applications | Phosphorus fate in stormwater applications | ||||||
Applications | [1] | [2] | ||||||
Chemical and physical properties | [3] | [4] | ||||||
Sustainability | Sustainable, but has current market constraints | Sustainable | ||||||
Potential contaminants | Minor risk - metals and polycyclic aromatic hydrocarbons (PAHs) | Low risk - possible chloride depending on preparation method | ||||||
Test methods | Not standardized but International Biochar Initiative widely used [5] | Not standardized but multiple methods available [6] | ||||||
Effects of aging | Varies with production method [7] | Decomposes slowly unless nutrients are added [8] | ||||||
Notes | Characteristics vary with feedstock and pyrolysis temperature | Coir must be composted or incorporated with compost, lime, fertilizer, and/or microbes |
1Exclusive of spent lime