(Liu TS, Loess and the environment) Much effort was put into the setting up of regional and local loess stratigraphies and their correlation (Kukla 1970, 1975, 1977).
But even the chronostratigraphical position of the last interglacial soil correlating to marine isotope substage 5e has been a matter of debate, owing to the lack of robust and reliable numerical dating, as summarized for example in Zöller et al.
For almost 150 years, this loess deposit was farmed with mouldboard ploughs and fall tilled, both intensely erosive.
At times it suffered erosion rates of over 10 kilograms per square meter per year.
Because these floodplains consist of sediment containing a high content of glacially ground flour-like silt and clay, they were highly susceptible to winnowing of their silts and clays by the wind.
Once entrained by the wind, particles were then deposited downwind.
The fertility of loess is not due to organic matter content, which tends to be rather low, unlike tropical soils which derive their fertility almost wholly from organic matter.Even well managed loess farmland can experience dramatic erosion of well over 2.5 kg /m per year.In China the loess deposits which give the Yellow River its color have been farmed and have produced phenomenal yields for over one thousand years.Soils underlain by loess tend to be excessively drained.The fine grains weather rapidly due to their large surface area, making soils derived from loess rich.