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<jats:title>Abstract</jats:title><jats:p>Soil fertility depletion is a major constraint to agricultural production in the Congo Basin and is aggravated by climate change. Therefore, agroforestry systems (AFS) are used to improve soil fertility and crop productivity. Indeed, <jats:italic>Pentaclethra macrophylla</jats:italic> and <jats:italic>Acacia auriculiformis</jats:italic> are among the most agroforestry species used in this basin. However, smallholders are limited in their choice of agroforestry species and the spacing. Hence, this study comparatively evaluated the effects of <jats:italic>P. macrophylla</jats:italic> (native) and <jats:italic>A. auriculiformis</jats:italic> (exotic) legume tree species on soil macronutrients and food crops’ yield during four cropping seasons. To do this, a multifactor trial design was implemented in Lobilo catchment, Congo Basin, with two tree species, four tree planting densities (T<jats:sub>1</jats:sub>: 2500 trees × ha<jats:sup>−1</jats:sup>, T<jats:sub>2</jats:sub>: 625 trees × ha<jats:sup>−1</jats:sup>, T<jats:sub>3</jats:sub>: 278 trees × ha<jats:sup>−1</jats:sup>; and T<jats:sub>0</jats:sub>: crop monoculture), and three intercrops (cassava, maize, and peanut). The results revealed that both agroforestry species did not significantly differ regarding their impact on soil macronutrients. The total nitrogen and the pH in soil have increased with the cropping seasons. With regard to the food crops, cassava and maize yield were greater under <jats:italic>P. macrophylla</jats:italic> than under <jats:italic>A. auriculiformis.</jats:italic> However, the 2500 trees × ha<jats:sup>−1</jats:sup> density negatively affected food crops’ yield and did not allow food crop production after the second cropping season. To maximize the positive effects of these AFS, it is essential to plant or co-plant these two agroforestry species at 625 trees × ha<jats:sup>−1</jats:sup> density. Future research could investigate other native species and include water and light interactions.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Agroforestry adoptition is gaining considerable traction in the temperate US with growing popularity and government incentives (e.g., the Partnerships for Climate-Smart Commodities Project) for systems with greenhouse gas mitigation potential. The identification of complementary species combinations will accelerate the expansion of temperate agroforestry. Since the mid-19th century, European timber plantations have taken advantage of the late-leafing habit of walnut (<jats:italic>Juglans</jats:italic> spp.) to grow a spring grain crop between the tree rows. Such alley cropping systems increase land-use efficiency and provide extensive environmental benefits. A parallel but underutilized opportunity in North American involves incorporating eastern black walnut (<jats:italic>Juglans nigra</jats:italic> L.) cultivars into alley cropping systems (ACS). Eastern black walnut, henceforth referred to as black walnut, is native to North America and exhibits architectural and phenological characters for reduced competition with winter cereal crops grown in alleys. Black walnut also produces nutritious nuts, and cultivars with improved kernel percentage and mass offer potential to cultivate the species as a domesticated orchard crop, as opposed to just the high-quality timber for which it is well-known. However, field observations suggest significant variation in tree architecture and phenology amongst cultivars, which is likely to influence complementarity with winter grains. Comprehensive characterization of trait genetic diversity is needed to best leverage germplasm into productive systems. Here, we review literature related to implementing ACS with consideration of cultivar-dependent traits that may reduce interspecific competition. While the focus is directed toward black walnut, broad characterization of other underutilized fruit/nut species will allow for robust diversification of ACS.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Silvopastoral systems (SPS) are strategic in neutralizing greenhouse gases (GHG) emissions in livestock production systems, particularly in the tropics. This research assessed the mitigation potential of SPS on the carbon footprint (CFP) neutralizing in one integrated livestock farm of cow-calf and pig production system in the Colombian Amazon. Annual carbon accumulation rate (ACAR) in MgCO<jats:sub>2</jats:sub>e ha<jats:sup>−1</jats:sup>y<jats:sup>−1</jats:sup>, was evaluated on living above-ground biomass including trees and shrubs &gt; 2 cm DBH and pasture, and leaf litter and below-ground biomass including coarse and fine roots, soil organic carbon 0–10 cm deep, and total ACAR adding up all components in live fences (LF), scattered trees (ST), fallows (FW), fodder bank (FB) and pastures (PT). The GHG emissions in MgCO<jats:sub>2</jats:sub>e ha<jats:sup>−1</jats:sup>y<jats:sup>−1</jats:sup> were accounted in CO<jats:sub>2</jats:sub> from liming, urea, fuel, electricity, and supplementation, CH<jats:sub>4</jats:sub> from enteric methane, manure, and organic fertilization and N<jats:sub>2</jats:sub>O from urine and manure. The C balance was obtained from the differences between ACAR of SPS on farm and the CFP per surface. Mean total ACAR expressed in MgC ha<jats:sup>−1</jats:sup>y<jats:sup>−1</jats:sup> were 9.0 ± 4.6 in FW, 7.0 ± 1.2 in LF, 5.5 ± 0.8 in ST, 4.2 ± 0.2 in FB and 2.9 ± 0.1 in PT. Mean CFP was 3.7 MgCO<jats:sub>2</jats:sub>e ha<jats:sup>−1</jats:sup>y<jats:sup>−1</jats:sup>, 5.3 MgCO<jats:sub>2</jats:sub>e Live Weight ha<jats:sup>−1</jats:sup>y<jats:sup>−1</jats:sup>, and 23.6 MgCO<jats:sub>2</jats:sub>e Live Weight Gain y<jats:sup>−1</jats:sup>. The CFP (area) can be neutralized with total ACAR value of 2.1 ha<jats:sup>−1</jats:sup> for LF, 1.6 ha<jats:sup>−1</jats:sup> for FW, 2.6 ha<jats:sup>−1</jats:sup> for ST, 3.5 ha<jats:sup>−1</jats:sup> for FB and 5.1 ha<jats:sup>−1</jats:sup> for PT. The <jats:underline>S</jats:underline>ilvopastoral systems have a higher potential for neutralizing GHG emissions than pasture-based scenario when considering the ACAR in above-ground biomass.</jats:p>

<jats:title>Abstract</jats:title><jats:p>This paper investigates the potential labour efficiencies and socio-cultural benefits of agroforestry for coffee smallholders practising low input production strategies. Employing both qualitative and quantitative methods, our case study of coffee smallholders in the highlands of Papua New Guinea, shows that despite managing very small holdings of coffee trees (&lt; 500 trees), productivity is challenged by labour shortages and by very low levels of farm inputs. Constraints on labour supply include barriers to mobilising women’s labour; competition for labour from alternative livelihoods; the absence of a market in hired labour; and the time, labour and income demands of the indigenous socio-economy. The indigenous social economy draws heavily on smallholders’ time, labour and coffee income, to the extent that there is little labour for coffee garden maintenance and little coffee income invested in other farm inputs. To address these input shortfalls we explore the potential of ecosystem services from shade-grown coffee to generate labour efficiencies to partly fill some of the unmet maintenance requirements of coffee gardens and to partly fill the role of other farm inputs. Coffee extension must become more holistic and consider smallholder families’ diverse livelihoods and recognise the enduring nature of the low input production strategy, its socio-cultural value, its role in determining life quality, and thus its resistance to change. Extension must align with, rather than challenge, the low input production strategy to promote the potential labour efficiencies and benefits of agroforestry to create more resilient, sustainable and culturally-enriching coffee-based farming systems.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Dutch policy strives to increase the amount of agroforestry. This pilot study aimed to research the forces and obstacles for this growth, in particular the role of various drivers of change. Therefore we conducted a case study in Lingezegen Park (near Arnhem, The Netherlands), using the transition model of Van der Meulen et al. as a basis. This model describes the connection between the transition of the social and physical realms. Important drivers of change influencing the social and physical realms in Lingezegen Park are the establishment of the park itself, but also the relations between and roles of the various stakeholders and the presence of a change agent. Data was collected via Rapid Rural Appraisal in combination with visualization studies and in depth interviews. The interviews were analyzed using a thematic analysis, with the help of NVIVO-software. The case of Lingezegen Park clearly shows that the transformation of the social realm intertwines with developments in the physical realm. The development of the park, both a change in the physical as well as the social realm, made way for new initiatives in sustainable farming systems such as agroforestry. The overall conclusion is that for the transition towards agroforestry, in addition to all kinds of on-site innovation, it is also necessary to take due account of exogenous important drivers of change, especially the functioning of local networks, land use planning and the presence of change agents. The combined effect of this largely determines opportunities for the growth of agroforestry.</jats:p>