Soil fertility along toposequence

In common with other undulating landscapes in Asia, rainfed rice on the East India Plateau (EIP) has traditionally been grown in hydrologic discharge areas or ‘lowlands’, but terracing has allowed it to encroach progressively upon ‘upland’ recharge areas. Hydrologic differentiation of the landscape and its implications for crop agronomy were documented in our previous research published in Agricultural Systems. Principles were established for application across the EIP. The present data relate to landscape differentiation in soil fertility, that has been less well documented. This is required to allow agronomic application of our research in two case-study watersheds across the EIP. Measurements of soil fertility in seven of 24 EIP Districts were used to evaluate variation between and within small watersheds differentiated along the toposequence into six land classes to reflect hydrology and land use (three with rice and three without, 36 fields/watershed).