Soil Solution Chemistry at Different Positions on Slope in a Conifer Plantation Forest

Autor: Naoko Tokuchi, Goro Iwatsubo
Rok vydání: 1999
Předmět:
Zdroj: Journal of Forest Research. 4:99-106
ISSN: 1610-7403
1341-6979
DOI: 10.1007/bf02762233
Popis: It is known that soil property varies along the slope. It suggests that soil solution chemistry also differs topographically. To determine the variation in soil solution chemistry within one watershed, soil solution chemistry at the different positions of the slope was investigated. Soil N transformation changed along the slope. NH4 + ratio to inorganic N (NH4 + + NO3 −) increased upslope. The tendency was verified by laboratory incubation. After incubation most of the mineralized N was nitrified at the lower part of the slope, while little nitrification occurred at the upper part of the slope. At the ridge and the backslope inorganic N form in soil solution was concomitant with inorganic N form by incubation. At the ridge NH4 + was predominant form in soil solution, at that time major anion was sea salt originated Cl−. From this, soil solution chemistry seems to be regulated by the external nutrient source at the ridge. In the second year of lysimeter installation NO3 − concentration increased in both sites and the ratio of NH4 + to inorganic N decreased. It was considered due to the effect of lysimeter installation. The lag time and the magnitude of NO3 − increase were different between the ridge and the backslope. It would be related with soil N transformation in pre-disturbance. The influence of disturbance were shown in other solute concentrations of soil solution.
Databáze: OpenAIRE