HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) An erratum has been published An erratum has been published Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Topper, K. F. Articles by Sabey, B. R. Search for Related Content PubMed Articles by Topper, K. F. Articles by Sabey, B. R. Agricola Articles by Topper, K. F. Articles by Sabey, B. R.

Sewage Sludge as a Coal Mine Spoil Amendment for Revegetation in Colorado¹

ABSTRACT

Use of digested municipal sewage sludge as an amendment for revegetation of a Colorado coal mine spoil was evaluated as a function of application rate. Plant growth responses to sewage sludge additions were compared to inorganic nitrogen (N) and phosphorus (P) fertilizer treatments on a grass pasture mixture. Sewage sludge additions resulted in significant increases in aboveground biomass and percent canopy cover over the control for two seasons of growth following sludge application. Sewage sludge rates < 83 Mg ha^–1 yielded greater plant growth than any of the inorganic N and P fertilizer treatments for both growing seasons. However, the lowest level of sewage sludge (14 Mg ha^–1) resulted in equivalent total N and total P concentrations of the seeded grasses when compared to the highest inorganic fertilizer treatments. The superior growth associated with sewage sludge additions at less than 83 Mg ha^–1 was likely due to measured increases in nutrient availability, improved physical condition of the spoil and a possible stimulation of microbial activity. The highest level of sewage sludge (83 Mg ha^–1) was detrimental to seeded grass growth when compared to the lower sludge rates in 1984. This may have been due to increased soluble salt concentrations, an increase in competition by invading annual forbs, and/or elemental toxicities. Further research is necessary to determine the exact causes.

Key Words: reclamation • invading annual forbs • life-form dominance • N and P equivalence

¹ Contribution of Agronomy Dep., Colorado State Univ., Fort Collins, CO 80523. Supported in part by the Colorado State Univ. Exp. Stn. Project no. 273.

² Supervisor of Soil Testing Lab, Utah State Univ., Logan, UT and Professor of Soil Science, Colorado State Univ., Fort Collins, CO, respectively.

Received for publication May 23, 1985.