Table 1 The cropping and management history of the Eniwa and Narita farms

Soil classification (WRB)

Vitric andosol

Vitric andosol

Silandic andosol

Silandic andosol

Unfertilised cultivation history (year)

56

–

41

–

Farm area (ha)

0.18

0.10

0.25

0.20

Tillage depth (cm)

10

40

10

20

Implements used

Rotary tiller

Mouldboard plough and rotary tiller

Rotary tiller

Rotary tiller

Mulch type

Weed and plant residue

Plant residue

Cornstalk

Composted fallen leaves

Mulch rates (dry) (kg ha⁻¹⁾

0.4

0.3

0.4

1.0

Nutrient inputs in mulch

TC: 35.0 %, TN: 2.4 %, C/N: 15, moisture: 41.6 %

TC: 35.3 %, TN: 1.9 %, C/N: 18, moisture: 80.3 %

TC: 38.9 %, TN: 1.7 %, C/N: 23, moisture: 59.6 %

TC: 35.8 %, TN: 2.0 %, C/N: 18, moisture: 27.2 %

Chemical fertilisers

Not use

Not use

Not use

N,P,K

Input of chemical fertilisers (t ha⁻¹)

0

0

0

0.5

Seed type

House seeds

Commercial seedling

House seeds

Commercial seeds