Yield and soil nitrous oxide emissions of Vigna radiata under contrasting fertilizer management practices in Maharashtra, India

Rationale
The Soil Protection and Rehabilitation for Food Security global program, commissioned by the German Federal Ministry for Economic Cooperation and Development (BMZ) and implemented by GIZ and partners in Benin, Burkina Faso, Ethiopia, India and Kenya, addresses the issue of soil degradation and loss of productivity and its impact on smallholder livelihoods. The primary goal – as the program title implies – is to support and promote the immediate function that protected, fertile soils play in terms of providing and sustaining food security. In addition improved agricultural management practices may have a role to play in terms of climate change mitigation. Besides increased productivity and climate change resilience, mitigation is the third pillar of climate smart agriculture (CSA). To assess the climate smartness of selected GIZ-supported soil protection and rehabilitation measures in the five countries, GIZ engaged CIAT scientists in the project Climate-smart soil protection and rehabilitation in Benin, Burkina Faso, Ethiopia, India and Kenya, which builds on CIAT’s expertise in both soil science and CSA.
As part of the Soil Protection and Rehabilitation for Food Security project, various improved soil and agronomic management practices where tested in the State of Maharashtra in India by experts of the Watershed Organization Trust, WOTR. A sub-set of these practices were assessed in detail in terms of their climate smartness and results summarized in a CIAT report (Birnholz et al. 2017a). The climate smartness assessment included a quantification of greenhouse gas (GHG) emissions using IPCC Tier-1 and Tier-2 empirical equations applying the Kalkulator; a Microsoft Excel based spreadsheet tool (Birnholz et al. 2017b). In addition, exemplarily, emissions of nitrous oxide (N2O) – a very potent GHG – from soils were measured in-situ in an on-farm agronomic field trial. Here, green gram (Vigna radiata; also known as mung bean) was exposed to contrasting fertilizer management practices. This brief report summarizes major findings, focusing on the agronomic performance (yield) and N2O emissions.