Effects of Organic Substrate Amendments on Selected Organic Fractions and Biochemical Parameters under Different Soils.

The application of organic substrates can affect soil respiration, dehydrogenase (DH-ase) activity, dissolved organic carbon (DOC), and humic acid (HA) fractions. This study aimed to evaluate the effects of five organic substrates in the organic fractions of degraded alluvial soil, acid sulfate soil, and sandy soils and the physicochemical properties of the soil. Soil samples were amended at a rate of 5 tons ha with (1) water hyacinth compost, (2) sugarcane filter cake compost, (3) biogas sludge-rice straw compost, (4) vermicompost, and (5) sludge.

Rapid and sensitive Nitrosomonas europaea biosensor assay for quantification of bioavailable ammonium sensu strictu in soil.

Knowledge on bioavailable ammonium sensu strictu (i.e., immediately available for cellular uptake) in soil is required to understand nutrient uptake processes in microorganisms and thus of vital importance for plant production.