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This chapter describes soil and water conservation measures for climate-resilient agriculture. It presents three interventions that can be used separately or in combination, depending on the context of the region: (1) integrating strips of forage grasses and legumes; (2) rainwater harvesting through tied ridges and ripping techniques; (3) constructing banks and ditches as part of an agroforestry system. The description of each technology, its benefits and application are discussed.

This chapter presents technologies for replacing the nutrients lost from cropped fields with external fertilizer sources in a manner that minimizes the consequences of too little or too much application. The technology of using industrial fertilizers, organic fertilizers, and application of farmyard manure and compost alone or in combination with industrial fertilizers are discussed in detail.

National governments across Sub-Saharan Africa include climate-smart agriculture (CSA) - context-specific interventions that support resilience, productivity, and climate mitigation-in plans and policies and strategies to jointly address climate change, agricultural production and rural livelihood goals. This paper synthesizes the evidence on field-based CSA management practices generated through ten years of research led by the CGIAR in Tanzania, an agriculturally diverse country in East Africa that has prioritized climate-smart agriculture practices in its climate adaptation strategies. Tanzania provides an illustrative example of how countries can use evidence of impacts, synergies and tradeoffs to prioritize activities for sustainable development.

Every year, oil sands mining in Alberta, Canada, results in a significant area of degraded land, which needs to be reclaimed. One of the sustainable reclamation strategies for a post-mining site is reforestation. In reconstructed mine sites, establishment of mixedwood boreal tree seedlings like trembling aspen (Populus tremuloides Michx) and white spruce (Picea glauca) along with ground cover is helpful to stabilise soil, minimise erosion and promote native vegetation restoration. Barley (Hordeum vulgare L.) and oats (Avena sativa) are the ground cover species that have been recommended for oil sands reclamation operations, but interactions of planted tree seedlings with ground cover and the growth response to fertilisation are not clearly understood. This study evaluated the effect of different rates of nitrogen (N), phosphorus (P) and potassium (K) fertiliser on the survival and growth of tree seedlings that were planted without and with barley and oats as ground cover. A lower survival rate was recorded for trembling aspen in response to N,P,K fertilisation. Trembling aspen was more sensitive than white spruce to ground cover competition and was negatively affected by barley and oats, especially with added fertiliser. Height, root collar diameter increment and root and shoot biomass yield of trembling aspen were significantly decreased when planted with ground cover, whereas white spruce was not affected. In general, adding fertiliser to these systems appears to be of very little benefit in enhancing the early establishment and growth of tree seedlings.

Several grass species are being screened to identify appropriate cover crops for stabilising recently reclaimed oil sands sites and for nursing newly planted tree seedlings on these sites. Besides soil erosion control, cover crops can influence the establishment success of tree seedlings by regulating the impacts of nutrients, moisture, and light on early survival and growth. However, interspecific interactions determining the net effects of these resources on tree seedling establishment in the Oil sands region are poorly understood. This study evaluated growth and yield responses of trembling aspen (Populus tremuloides) and white spruce (Picea glauca) seedlings to fertiliser, soil moisture, and cover crop species using the bioassay factorial experiment. The objective was to characterise the effects of interspecific interactions on growth of tree seedlings. Barley (Hordeum vulgare) and oats (Avena sativa) were used as test crops because these herbaceous species are being recommended for oil sands reclamation operations. Significant height and root collar diameter (RCD) growth increments of tree seedlings after fertilisation were attributed to differential growth rates between tree species. In contrast, soil moisture stimulated height, shoot and root biomass yields of tree seedlings. Cover crops species largely controlled growth and yield responses of tree seedlings to fertiliser and soil moisture. Even with fertilisation, RCD increment and shoot biomass yield were reduced by 26–51% and 36–68%, respectively, relative to the no grass treatment (grass control). These effects increased with increasing fertiliser and moisture levels, indicating enhanced access to growth resources by tree seedlings after alleviating interspecific competition. Comparatively the suppressive effect of barley was higher than that of oats probably due to a combination of vigorous growth and possible allelopathic effects. Apparently, weed competition may adversely affect early growth and yield of tree seedlings on reclaimed oil sands sites by inducing or augmenting the effects of nutrient limitation and moisture stress. However, revisiting fertiliser recommendations to account for nutrient uptake by the competing vegetation may be the appropriate approach for enhancing tree seedling growth in the oil sands region because cover crops are planted for stabilising recently reclaimed sites. This approach, however, need to consider the observed species-specific response to weed competition.