Does integrated soil fertility management increase returns to land and labor?
研究分析了综合土壤肥力管理（ISFM）三种核心做法及其组合对埃塞俄比亚小农户土地和劳动生产率及净作物价值的影响，发现所有做法均提升生产率，但有机肥加改良种子的组合可能比含无机肥的组合更有利。
Abstract Integrated Soil Fertility Management (ISFM) is promoted to enhance soil fertility and agricultural productivity among smallholders. Its core is the combined use of organic and inorganic fertilizers with improved crop varieties. Adoption of these practices potentially involves additional monetary and labor investments, and it remains unclear whether these pay off. This study analyzes the effects of the three core ISFM practices and their combinations on key agricultural outcomes, including land and labor productivity as well as net crop value, in which we account for the shadow costs of unpaid labor. We employ a multinomial endogenous switching model to original survey data from over 6000 teff, maize and wheat plots owned by around 2000 households in Ethiopia. All ISFM practices and their combinations increase land and labor productivity, despite higher labor demand, with the largest effects stemming from the joint use of all three practices. Effects on net crop value are positive for most combinations, but suggest that organic fertilizer with improved seeds may be more beneficial compared to combinations with inorganic fertilizer. The importance of organic fertilizer applications is also supported by our regionally disaggregated analysis that reveals important agroecological heterogeneity.