水保所知识产出(1956---)知识库

Seasonal changes in respiration and the components of four reconstructed soils
(gravel + meteorite + lou; gravel + shale + lou; gravel + sand + lou; and gravel + soft rock + lou) in barren
gravel land were monitored using the soil carbon flux measurement system. The results showed that
(1) the monthly average respiration rate and the rates of the components in the four reconstructed
soils were the highest in summer and lowest in winter. In winter, the monthly average respiration
rates of the four reconstructed soils were not different (p > 0.05). In summer, the monthly average
respiration rate of the sand or meteorite reconstructed soil was different from that of the other three
(p < 0.05). (2) The heterotrophic and autotrophic respiration rates were different between the four
reconstructed soils (p < 0.05). The contribution of heterotrophic respiration to total respiration in
the four reconstructed soils was greater than that of autotrophic respiration throughout the year.
In winter, autotrophic respiration accounts for the smallest proportion of total respiration. As the
temperature rises, the proportion of autotrophic respiration to total respiration gradually increases
and peaks in summer. In summer, the proportion of heterotrophic respiration in the total respiration
is the smallest. With the decrease in temperature, the proportion of heterotrophic respiration in
total respiration gradually increases and peaks in winter. (3) The maximum and minimum values
of the monthly average respiration rate of the four reconstructed soils coincided with the months
of maximum and minimum soil temperature. The soil volumetric water content changed with the
amount of precipitation. The correlation between soil respiration and temperature was greater than
that between soil respiration and volumetric water content. (4) The correlation in seasonal variation
between respiration of the four remodelled soils and hydrothermal factors in the study area can be
characterised by an exponential function and power-exponential function.