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Based on the source-sink landscape theory and the principles of ecosystem services, the minimum cumulative resistance (MCR) model was modified, where the urban center construction land was taken as the expansion source, and the contribution rate of ecological land ecosystem services value was considered as the resistance coefficient. With the modified MCR, the urban spatial expansion process of Xintang Town, Guangzhou City was successfully simulated, and, based on the protection of ecological security pattern, the optimum path for reconstructing urban land space was put forward. The simulated urban spatial expansion short path in 1988-2008 was in accordance with the real situation. By the modified MCR, the urban space was divided into four zones of high, higher, medium, and low resistance, with the area of 80.84, 78.90, 24.26, and 61.88 km2, respectively. The expansion path of the urban space was along the route from low to medium and then to high resistance zones successively. The land suitable for eco-protection and construction had an area of 159.74 km2 and 86.14 km2, while the ecological conflict area (17.37 km2) was mainly located in higher and high resistance zones, being 10.38 and 6.99 km2, respectively. The modified MCR could not only effectively reflect the distribution area of urban land use and the conflict relationship between urban construction and ecological protection, but also reasonably judge the best developmental short path for urban spatial expansion.

The responses of the autumn phenophase of 20 woody plants to climate warming in Beijing in 1962-2007 were analyzed by using the plant phenological data and the meteorological data obtained from Chinese Phenology Observation Network of Chinese Academy of Sciences. The results showed that in Beijing region, the end date of autumn defined by phenology was extended remarkably at an average rate of 3.2 d x 10 a(-1), while the onset of autumn defined by phenology remained essentially unchanged, resulting in a 14 d prolongation in autumn in 1962-2007. The timing of first leaf coloring change for the woody plants showed an average delaying rate of 4.9 d x 10 a(-1), and the main affecting factor was the mean minimum temperature. Climate warming was probably the main reason for the delaying trend in autumn phenophase of woody plants in Beijing during the study period.