This Handbook was developed by the Department of Agricultural Land Resources Management (DALRM, GDA), Department of Agricultural Engineering (DAEng, GDA), Department of Extension for Agriculture, Forestry and Fisheries (DEAFF, MAFF), SmartAgro, CIRAD, Swisscontact, CE SAIN (RUA), Faculty of Agricultural Engineering (RUA) and were funded in whole or partly by Innovation for Sustainable Agriculture (ISA), financed by Happel Foundation, the Marcuard Family Office, among other donors, and also a part of the Swisscontact Development Programme, which is co-financed by the Swiss Agency for Development and Cooperation (SDC), Federal Department of Foreign Affairs FDFA; Kansas State University; the Center of Excellence on Sustainable Agricultural Intensification and Nutrition (CE SAIN, RUA) through the support of the United States Agency for International Development (USAID) Bureau for Resilience and Food Security/Center for Agriculture-led Growth under the Cooperative Agreement # AIDOAA-L-14-00006 as part of Feed the Future Innovation Lab for Collaborative Research on Sustainable Intensification (SIIL); the project Water Resources Management and Agroecological Transition for Cambodia (WAT4CAM) funded by the French Agency for Development (AFD) and the European Union (EU) (Grant agreement WAT4CAM-CS/04-02). Any opinions, findings, conclusions, or recommendations expressed here are those of the authors alone”.