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Rwanda's agricultural sector is facing severe challenges of increasing environmental degradation, resulting in declining productivity. The problem is likely to be further aggravated by the growing population pressure. A viable pathway is climate smart agriculture, aiming at the triple win of improving food security and climate change adaptation, while contributing to mitigation if possible. The Government of Rwanda has initiated ambitious policies and programs aiming at low emission agricultural development. Crop focused policies include the Crop Intensification Program (CIP) which facilitates access to inorganic fertilizer and improved seeds. In the livestock subsector, zero-grazing and improved livestock feeding are encouraged, and the Girinka program provides poor farm households with a crossbred dairy cow. In this study, we aimed at assessing the potential impact of these policy programs on food availability and greenhouse gas (GHG) emissions of 884 households across different agro-ecologies and farming systems in Rwanda. Household level calculations were used to assess the contribution of current crops, livestock and off-farm activities to food availability and GHG emissions. Across all sites, 46% of households were below the 2500 kcal MAE − 1 yr − 1 line, with lower food availability in the Southern and Eastern Rwanda. Consumed and sold food crops were the mainstay of food availability, contributing between 81.2% (low FA class) to 53.1% (high FA class). Livestock and off-farm income were the most important pathways to higher FA. Baseline GHG emissions were low, ranging between 395 and 1506 kg CO 2 e hh − 1 yr − 1 per site, and livestock related emissions from enteric fermentation (47.6–48.9%) and manure (26.7–31.8%) were the largest contributors to total GHG emissions across sites and FA classes. GHG emissions increased with FA, with 50% of the total GHG being emitted by 22% of the households with the highest FA scores. Scenario assessment of the three policy options showed strong differences in potential impacts: Girinka only reached one third of the household population, but acted highly pro-poor by decreasing the households below the 2500 kcal MAE − 1 yr − 1 line from 46% to 35%. However, Girinka also increased GHG by 1174 kg CO 2 e hh − 1 yr − 1 , and can therefore not be considered climate-smart. Improved livestock feeding was the least equitable strategy, decreasing food insufficient households by only 3%. However, it increased median FA by 755 kcal MAE − 1 yr − 1 at a small GHG increase (50 kg CO 2 e hh − 1 yr − 1 ). Therefore, it is a promising option to reach the CSA triple win. Crop and soil improvement resulted in the smallest increase in median FA (FA by 322 kcal MAE − 1 yr − 1 ), and decreasing the proportion of households below 2500 kcal MAE − 1 yr − 1 by 6%. This came only at minimal increase in GHG emissions (23 kg CO 2 e hh − 1 yr − 1 ). All policy programs had different potential impacts and trade-offs on different sections of the farm household population. Quick calculations like the ones presented in this study can assist in policy dialogue and stakeholder engagement to better select and prioritize policies and development programs, despite the complexity of its impacts and trade-offs.

Crop productivity in Rwanda is declining as a result of intensive farming on steep slopes, which leads to soil loss and declining soil fertility particularly in the northern highlands. Slow-forming terraces have been widely adopted in the northern highlands of Rwanda to control soil erosion however not much been done to evaluate their efficiency. We hypothesized that slow-forming terraces reduce soil loss and soil fertility gradients compared with non-conserved land. A field experiment compared the soil erosion rates and fertility gradients of 20+ year old terraces where sole grass strips ( Pennisetum purpureum ) or grass strips combined with infiltration ditches were used with those of land where no soil conservation technologies were applied. The experiment was conducted in the year 2010 on three landscape positions (Upperslope, Hillslope and Footslope) along a representative toposequence using farmers’ fields where potato and maize were grown in two consecutive cropping seasons. The highest annual soil loss (41.5 t ha −1 ) was recorded with plots receiving no soil conservation practices while the lowest annual soil loss (18 t ha −1 ) was recorded with grass strips combined with infiltration ditches. The slow-forming terraces showed a marked “within” spatial difference in both soil quality and crop yield. The soil in the lower part of the terraces showed as much as 57% more organic carbon content and 31% more available phosphorous than the soil in the upper part. Organic carbon (OC) was higher (OC = 2.1%) on the upperslope than on hillslope (OC = 1.9%). Less than 2.3 t ha −1 of the mean potato yield (23 t ha −1 ) and only 0.5 t ha −1 of the mean maize yield (5 t ha −1 ) were recorded on the uppermost third of the terraces on all three landscape positions. The marked soil fertility gradients indicate that the sustainability of slow-forming terraces is threatened, unless a site-specific fertilizer strategy is developed. For the sustainability of these terraces, the current practice of “harvesting” the fertile soil from the lower edge of the grass strip and using it as fertilizer for the nutrient deficient upper parts of terraces needs to be stopped.