Geoscience Reference
In-Depth Information
cultivation using lithic mulching. This technique
—
adding a layer of stones on top
of fertile soil
is used to curb erosion and limit evaporation. There are many
instances of lithic mulching documented around the world.
45
—
India
South Asia is the home of some of the most ancient human settlements. The
Harappan Civilization in the Indus valley dates to 3200 BCE and thrived in Mo-
henjodaro from agriculture, grazing and trade until ca 1900 BCE.
46
The archaeo-
logical record of terraced
elds allows us to assume knowledge about water and soil
retention having been available at that time. In the Ganges valley, the situation is
similar. Archaeological evidence shows that wild rice was being used as early as
9000
8000 BCE at sites near Allahabad, but reliable evidence from pollen of
settled agriculture for most of the valley does not appear until about 6000 BP
(
-
4000 BCE).
The testimony of the Vedas, religious texts of uncertain age, offers a coarse
terminology for soils. Land was classi
*
ed as waste (ushara), especially when
saline, pasture (gochara/vraja/ghoshtha) and cultivated (karsha). Cultivated land
could be furrowed (sitya) and plowed (halya). The Vedic texts show that ancient
Indians acknowledged the positive effect of alluvium deposition by rivers, and
distinguished two types of riverbed erosion. One text, the Vishnu Purana (1st
century CE), offers distinctions of soils by color (black, white or yellowish, red or
blue, and golden) and texture or morphology, namely gravelly and hilly or boul-
dery. Soil quality is connected to water quality in another of these texts, the Brihat
Samhita, which also discerns soil and rock type by depth. The Manusmriti,a
compilation of Hindu law composed in its
nal form in the 2nd or 3rd century CE,
advises against the use of iron-tipped plows because they injure the earth and its
creatures. Another piece of evidence for soil knowledge in India is contained in the
Arthashastra, a treatise on how the well-being of a people should be organized,
plausibly dated to 3000 BCE. In the chapter on the duties of the superintendent of
agriculture (XXIV), the existence of systematic agricultural knowledge is pre-
sumed. The superintendent must either possess such knowledge himself or be
assisted by those who do. The text advises on suitable lands for particular crops,
without giving a classi
cation
—
it has referred readers to the agricultural knowledge
beforehand
own by water
(parivahanta) are good for long pepper, grapes and sugar-cane. The text does also
give some indication of manuring practices, stating that water-pits at the root of
trees are to be manured with the bones and dung of cows on proper occasions.
Likewise, sprouts of seeds are to be manured with a fresh haul of minute
—
but informs e.g. that lands that are frequently over
shes and
45
Lightfoot (
1997
).
46
Wasson (
2006
).
