Sulphur availability on interior lodgepole pine sites

• Main Author: Kishchuk, Barbara Ellen
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/9505

Sulphur deficiencies limit the response of lodgepole pine to nitrogen fertilization on some sites in the British Columbia interior. Soil sulphur properties, foliar nutrition, and response to fertilization were investigated on sulphur-deficient and sulphur-sufficient sites. The soil sulphur constituents most closely associated with sulphur availability were determined. Cycling of soluble inorganic-sulphate through organic-sulphate in mineral soils is the process limiting sulphur availability on sulphur-deficient sites. Sulphur cycling appears to be further limited by low concentrations of organic carbon. A model containing foliar nitrogen, foliar sulphate-sulphur, and soil organic carbon concentrations was a better predictor of lodgepole pine growth response to nitrogen fertilization than a model containing only foliar nitrogen and sulphate-sulphur. Sulphur concentrations in lodgepole pine foliage remained elevated several years after fertilization with sulphate-sulphur. Soil organic-sulphate concentration increased with elemental sulphur fertilization, although seedling biomass was similar on fertilized and unfertilized soils. The susceptibility of interior lodgepole pine sites to sulphur deficiencies is related to both pedogenetic processes and management practices.