Geoscience Reference
In-Depth Information
disruption of the nutrient cycle of a forest ecosystem will result in deteri-
oration in drainage water chemistry, such as unusual elevation of stream
NO
3
concentrations or eutrophication of lake water.
Biogeochemical dynamics have been investigated in tandem with
groundwater monitoring in a temperate forest catchment in Japan, to deter-
mine the effect of the partial dieback of dominant tree stands on nutrient
cycling and streamwater chemistry, especially temporal and spatial changes
in the solute concentrations related to nitrogen dynamics in soil and ground
water.
4
2. Field Investigation
The field investigation has been carried out in a forested headwater catch-
ment (0.68 ha, the Matsuzawa catchment) in the Kiryu Experimental
Watershed in central Japan (35
◦
N, 136
◦
E). The catchment is underlain
by weathered granitic rocks. The soils are predominantly cambisols. Detail
site descriptions were in Refs. 4 and 5 and Fig. 1.
Fig. 1. (a) Location of the Kiryu Experimental Watershed. (b) Surface topography and
observation apparatus of the Matsuzawa. UG512, DG75, and DG190 indicate the obser-
vation wells. The two solid squares indicate points where soil solutions were sampled.
S: spring point; W: gauging weir; Open circles indicate other wells. (c) Longitudinal sec-
tion along the dotted line in the panel (b) and groundwater condition (after Ohte
et al
.
4
).
