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The 1951–2004 time series of annual sediment supply from the Yangtze were analyzed using the wavelet method. Coastal bathymetric data were processed using the Arc‐GIS software. A typical intertidal flat was measured from May 2002 to August 2005 for comparison of bed levels before and after the Three Gorges Dam (TGD). There is a significant decreasing trend in riverine sediment supply since late 1960s, which is attributed mainly to the dam constructions. TGD reduced the sediment load to147 mt/yr in 2004, only 35% of the average. In response to this drastic decrease, the deltaic coast is turning from progradation to recession. We predict that the Yangtze sediment supply will further decrease and coastal erosion will be intensified in the coming decades, which poses a great challenge to coastal management.

[1] To evaluate the response of river discharge to anthropogenic impacts and climate variability over the Industrial Period, we reconstructed past series of monthly discharge from three gauges on the main river of the Yangtze by means of regression (making use of the cross correlation among the gauges) and analyzed the integrated data (the observed series of discharge with missing values filled by reconstructed values) for the period 1865-2008 in relation to human activities and climate variability. The correlative coefficients between observed and predicted discharges at the three stations for the gauging period are R 2 = 0.90-0.96 (n = 827-1557). The integrated time series of discharge to the sea shows periodicities of ∼7, ∼14, and ∼38 years, and we found significant decreasing trends in annual discharge (−11%) and monthly discharge from August to November (−47% for November) and an increasing trend in discharge in January (+30%) and February during the dry season. These trends are mainly attributed to human impacts, in particular, reservoir construction and water consumption. It is estimated that these trends will continue in the future decades of this century because of the influence of the South-toNorth Water Diversion Project as well as increased water consumption and the construction of new dams within the river basin.

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Corticosteroids are prescribed for the treatment of many medical conditions and their adverse effects on bone, including steroid-associated osteoporosis and osteonecrosis, are well documented. Core decompression is performed to treat osteonecrosis, but the results are variable. As steroids may affect bone turnover, this study was designed to investigate bone healing within a bone tunnel after core decompression in an experimental model of steroid-associated osteonecrosis. A total of five 28-week-old New Zealand rabbits were used to establish a model of steroid-induced osteonecrosis and another five rabbits served as controls. Two weeks after the induction of osteonecrosis, core decompression was performed by creating a bone tunnel 3 mm in diameter in both distal femora of each rabbit in both the experimental osteonecrosis and control groups. An in vivo micro-CT scanner was used to monitor healing within the bone tunnel at four, eight and 12 weeks postoperatively. At week 12, the animals were killed for histological and biomechanical analysis. In the osteonecrosis group all measurements of bone healing and maturation were lower compared with the control group. Impaired osteogenesis and remodelling within the bone tunnel was demonstrated in the steroid-induced osteonecrosis, accompanied by inferior mechanical properties of the bone. We have confirmed impaired bone healing in a model of bone defects in rabbits with pulsed administration of corticosteroids. This finding may be important in the development of strategies for treatment to improve the prognosis of fracture healing or the repair of bone defects in patients receiving steroid treatment.

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