Assessing the returns to water harvesting: A meta-analysis.

This study presents the results of a meta-analysis of the peer reviewed literature on water harvesting technologies, with a focus on the crop yield impacts of water harvesting in semi-arid Africa and Asia. Main aim of the analysis is to assess whether water harvesting significantly improves crop yields, and whether the type of water harvesting technology and the quality of the rainy season correlate with the change in yield. We find that water harvesting improves crop yields significantly, and that the relative impact of water harvesting on crop yields is largest in low rainfall years. Smallholder farmers may still be reluctant to invest in water harvesting, however, as in regions with low agricultural productivity the returns to investment are limited. Finally, our review of the literature suggests that there is only a limited number of studies that has systematically evaluated the crop yield impacts of water harvesting technologies. More work is needed to strengthen the scientific knowledge base

INTERGOVERNMENTAL IMPLEMENTATION MANDATES: A STUDY OF TWO LAND USE REGULATORY POLICIES

This paper examines the implementation mandates and experiences associated with two intergovernmental regulatory policies, one at the federal-state level and the other a t the state-control level. The policies are the Federal Surface Mining Control and Reclamation Act of 1977 and the Florida Growth Management Act of 1985. These experiences suggest that implementation mandates, a t least with respect to intergovernmental regulatory policies, are not as effective as logic and rational argument might dictate. Copyright 1989 by The Policy Studies Organization.