Geoscience Reference
In-Depth Information
bones and hoofs, chicken feathers and lime in various places, a total of 80 different
substances has been counted. Seeds were prepared for sowing by mixing them with
manure or compost (for which very detailed and complex recipes exist) and non-
organic soil amendments such as river mud were recommended, the latter for wheat
cultivation. As late as the 1930s, marine
sh too small to market as food were dried
and sold as fertilizer, a practice which was certainly unsustainable with regard to the
tted the nutrient balance of soils.
35
Chinese farmers and writers
knew that the application of the wrong type or amount of fertilizer could do more
harm than good and that some fertilizers could
sheries, but bene
crops.
Rice paddies needed and had to be treated with special care. Application of fer-
tilizing agents was time-sensitive. One manual gives a detailed prescription involving
four different types of fertilizers.
'
burn
'
“
You should not put down manure too early or its
strength will not last [
] Only at sowing time must river mud be applied as a base, and
although its strength is lasting and dissipates slowly, by midsummer you should apply
a little potash or oil-cake, which also dissipates slowly and is long-lasting. Only at the
end of the summer or the beginning of autumn should you apply nightsoil, by which
time it will have the double effect, so that the rice panicles will grow very long
…
.
36
”
elds
cover large areas of the Chinese south, bearing witness to a technique of human
creation of fertile soil. A hardpan soil layer on the bottom of the paddy is con-
sciously created to prevent water seepage, with a system of ditches, ridges and
dykes to control water
The creation of rice paddies is a long-lasting intervention into soils. Paddy
ow. Yields are higher in paddies which are several years
old. Other special types of
elds (y
ü
thien), diligently ridged spaces to reclaim swampy areas such as in the Yangtze
delta, where the lakes had been turned into
elds known in Chinese history are poldered
elds by the 12th century CE. On
marshy lake shores,
oating
elds were created from wooden frames,
lled with
mud and water-weed, enabling the planting of crops on arti
cial soils.
Terraces are a feature of many agricultural systems. In China, they were con-
sidered bene
cial to prevent erosion, conserve soil moisture and nutrients, and
improve yields. Terracing allows the cultivation of slopes otherwise un
t for irri-
gated agriculture and hence, enlarges the cultivable area. The Chinese agricultural
writers distinguish between stone-walled terraces and
elds formed from piled-up
soil. Terraces are labor intensive to build and maintain, but the overall improvement
was obviously considered to outweigh the effort.
Chinese agriculture was based on cereals and vegetables, with pig, poultry and
sh as the main sources of animal protein. Interventions into soils were undertaken
consciously, and the extant manuals are proof of intricate and detailed technical
knowledge, based on systematical observations of key features of soils, both their
relation to the water-table and their situation with regard to the relief of the land-
scape. A system of soil classi
cation was the basis for decisions on crops, rotations
and the timing, amount and quality of fertilizer to be applied, but also for the siting
35
Muscolino (
2008
).
36
Bray and Needham (
1984
).
