conformed by the changes of the total contributions of land use/
cover inTable 6.
It could be found from Table 6that the contribution of
temperature for the types of built-up and water was higher,
followed by fish pond and bare land in the Pearl River Delta. As
the water changed less during the study time period, it had less
influence on regional temperature changes. Expansions of builtup area became the main contributor for the regional temperature
rise (0.11 °C). Although the semi-bare land was not big for its
contribution of temperature per unit area, it still became an
important contributor to the temperature rise (0.10 °C) because of
its large area change. The calculated results showed that the
contribution of semi-bare land was almost equal to that of builtup type, both of them contributed more than 75% (0.21 °C) to the
regional temperature rise (0.27 °C) in the Pearl River Delta. If the
contribution of cropland (0.07 °C) was included, it nearly
matched the regional total contribution. The results suggested
that the impact of land use/cover change on temperature rise
mainly occurred in the types of built-up, semi-bare land and
cropland, where great area changes had happened over the study
time period in the Pearl River Delta. As the changes of semi-bare
land and cropland were largely caused by urbanization, it could
be concluded that urbanization was a major contributor to the
regional temperature rise. If the future 10 years' urban area
expands in same rate as that in the time period of 1990 to 2000,
the contribution of land use/cover changes to the regional
temperature rise will reach almost 1 °C when urban area
expanded from 0 to 30 percent in the PRD (Table 6).