Soil physical and biological properties often change when different cropping, tillage, or management systems are imposed. Changes occasionally occur quickly, but usually become evident only after months or years. Infiltration rates are affected by several soil properties and may provide the most sensitive indication of changes in soil properties. To evaluate the use of infiltration measurements for detecting changes in soil properties, we conducted infiltration tests on a cropping systems experiment, a tillage experiment, and two beef cattle grazing experiments. In Pennsylvania, significant changes in infiltration rates did not occur until more than four years after converting from a conventional to a low-input cropping system. Infiltration rates were higher on 14th-year no-till plots compared with moldboard plow and chisel treatments in an Iowa tillage study. Earthworm populations and activity were highest in the no-till treatment. Infiltration rates correlated negatively with increased stocking rates in a long-term beef grazing study in Oklahoma. The number of earthworms did not correlate positively with infiltration in this study, suggesting a complex interaction. A short-term study of overwinter beef corn-stalk grazing in Iowa did not show consistent patterns in infiltration rate or other soil properties with different stocking rates. Infiltration appears to be a good indicator of soil structural changes associated with cropping, tillage, and management systems.

In on-farm studies of sustainable agriculture, farmers often have been classified as sustainable according to their organizational affiliation; self identification; or use or non-use of a particular production practice or input, usually synthetic chemicals. Because this is a great oversimplification, researchers recently have been incorporating several dimensions of sustainability into a composite measure. Typically this is a relative measure of sustainability, with scores assigned by comparing individual farmers' practices to those used by all farmers. In contrast, in the farmer sustainability index (FSI) presented here, practices are scored according to their inherent sustainability. We report on the development of an FSI in a case study involving 33 production practices used by 85 cabbage farmers in Malaysia. We describe its underlying principles, the procedure and rationale for scoring each sustainability item, and the result of combining the constituent items into a composite index.

The development of sustainable agriculture in India has been limited by the absence of data on the agricultural and economic viability of ecological agriculture and its longterm prospects. This paper describes a two-year study of seven farm pairs, each consisting of one ecological and one comparable conventional reference farm. The ecological farms differed significantly from the conventional farms in the number of crops grown, the dependence of crop activities on external nutrients, and the number of techniques used to maintain soil fertility and create plant diversity. No significant economic differences were found. Gross income, variable costs, gross margin and net cash income per hectare were in the same range for the two groups of farms. The two groups were similar in average yields for major crops, days of labor per hectare, and total returns per day of labor.