The loess soils of China as records of climatic change

The sequence of palaeosols and intervening loess units in North China provi des a sensitive, detailed record of global climatic changes over the last 2 .5 million years. Although various depth functions of properties, notably m agnetic susceptibility, have been successfully correlated with oxygen isoto pe records from the deep oceans, there is a need to improve our understandi ng of such proxy measures used to infer past climates. For instance, pedolo gists are well placed to address some of the uncertainties surrounding the origin of the enhanced magnetic susceptibility (MS) values in palaeosols, a nd the reconstruction of palaeoprecipitation patterns by application of MS climofunctions. There are few published field descriptions of the soils bur ied in the loess, and those available often fail to recognize their accreti onary and polycyclic nature. Field and micromorphological techniques enable finely detailed reconstructions of the pedogenic and sedimentary signals h eld in both palaeosol and loess units. Micromorphology, in particular, has provided detailed environmental information on successive pedosedimentary d evelopmental stages at several sites in the Loess Plateau of China. This ap proach re-focuses attention on the local, climatically sensitive mechanisms that underpin the inferred global patterns of climate.