Takashi Sakamaki

Summary Spatial scale of processes is necessary information to design appropriate ecosystem research and management. In‐stream ecological processes are tightly linked with their adjacent terrestrial environment and impacted by modifications of riparian environments, particularly in small, forested streams. Quantitative understanding of how the dynamic coupling of these adjacent ecosystems varies along stream continua is necessary to enhance stream research and management. In temperate, forest‐do

In a long-term and a short-term study of 2 estuarine intertidal flats (sandy and muddy), sediment carbon contents were measured every 2 wk over 2.5 yr and daily for a 2 wk period, respectively. During the long-term study, current velocity was measured twice (for periods of 8 wk and 6 wk). During the short-term study, sediment traps were also deployed. In both tidal flats, sediment carbon content fluctuated but had no long-term trend, indicating dynamic equilibrium. Amplitude, period and mechanis

We compared effects of particulate organic matter (POM) transported from small rivers (POM R ) on chemical properties of sediment and diets of primary consumers in 3 estuarine tidal flats with different watershed characteristics in southwestern British Columbia, Canada. The source rivers (0.1 to 1.9 m 3 s -1 , annual mean) flowed through forested and urbanized areas (FR) or through agricultural areas (AG1 and AG2). The C:N ratio of POM R was significantly higher in FR (8.6 to 10.1) than in AG1 a

The study objective was to clarify how the growth stages of the Pacific oyster Crassostrea gigas affect selective suspension-feeding of particulate organic matter (POM) and the composition of biodeposits. A day-long (22 h), continuous-flow mesocosm experiment was conducted with 3, 15, and 27 mo old oysters. The suspended particulate matter (PM), settled PM (mostly biodeposits in the oyster mesocosms), and oyster soft tissues were analysed to determine the content of fatty acids, organic carbon,

Summary 1. The magnitude and spatial scales of human effects on stream habitats need to be correctly measured to achieve sound ecosystem management. We investigated whether the biogeochemical properties of fine particulate organic matter (FPOM) might be indicative of reach‐scale vs. catchment‐scale effects on forested stream ecosystems. 2. Along each of three forested streams, we established 4–5 sampling stations at 0·6–2·0‐km intervals, which represent a range of local riparian forest condition