Details

Autor(en) / Beteiligte

• Cartron, J.M
• Weil, R.R

Titel

Seasonal trends in soil nitrogen from injected or surface-incorporated sewage sludge applied to corn

Ist Teil von

• Communications in soil science and plant analysis, 1998, Vol.29 (1/2), p.121-139, Article 121

Ort / Verlag

Philadelphia, PA: Taylor & Francis Group

Erscheinungsjahr

1998

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Use of sewage sludge on cropland may contribute to nitrate leaching or runoff from fields if mineralization of organic nitrogen (N) is not in synchrony with crop N uptake. Differences in sludge application method may influence sludge N use efficiency. A two-year field experiment was conducted to determine how method of applying lime-stabilized digested sewage sludge in the spring affected seasonal patterns of soil mineral N. Sludge rate was such as to supply 157 kg ha(-1) plant available N as determined by State of Maryland regulations. Corn (Zea mays) yield in year 2 and corn earleaf N at tasseling in both years were significantly lower for surface-incorporated sludge than for injected sludge, although equivalent N was applied to both. Vertical distribution of soil ammonium-N and nitrate-N within the surface 30 cm of soil in year 2 suggested that, compared to injected sludge, surface-incorporated sludge lost more nitrate by leaching before the period of rapid plant N uptake. Release of nitrate was delayed by at least one month with injected as compared to surface-incorporated sludge. In both years, soil pH and electrical conductivity measured about one month after sludge application were sufficiently high to inhibit nitrification in the injected sludge band. Residual mineral soil N remaining in the upper 30 cm of soil after plant N uptake ceased in fall was greatest with injected sludge in both years. Delayed nitrification in the injected band should be considered in planning method and timing of sludge applications to cropland.