Agroforestry Systems最新文献

Slash-and-mulch agroforestry systems can reduce greenhouse gas emissions by mulching the vegetation instead of burning it. This mulch layer then contains greater stocks of organic material than after burning, making it a potential source of N₂O and CH₄ efflux during decomposition. We examined N₂O and CH₄ efflux from slash-and-mulch AFS using a two-way factorial design: with and without P + K fertilization, and with and without a nitrogen-fixing tree (Inga edulis). We hypothesized that inclusion of N-fixing trees would increase N₂O efflux and that CH₄ efflux would increase due to increased soil moisture with mulching. We measured trace gas fluxes prior to the end of Rotation 1, and after mulching to begin Rotation 2. N₂O efflux increased with I. edulis during the year prior to, but not after, mulching. No differences by treatment were detected for CH₄ efflux before or after mulching. Site conversion from secondary forest to Rotation 2 resulted in a 130% increase in N₂O efflux and a 430% decrease in CH₄ efflux. The CO_2e increase of 2,400 kg ha⁻¹ was an order of magnitude less than estimated releases of trace gases from burning (38,400 kg ha⁻¹). For both N₂O and CH₄, land disturbance during mulching led to larger changes in trace gas fluxes than either P + K fertilization or inclusion of the N-fixer. The order-of-magnitude estimates of trace gas release as CO_2e from mulching and the addition of N-fixers appears to be less than that from burning alone.

Within the search for sustainable food production methods, a system that has recently seen a surge in attention is the temperate food forest. Research into the functioning of these complex agroforestry systems is taking off, yet the variety in systems referred to as food forests has not been thoroughly explored. We therefore used site surveys and interviews to gain insight in biophysical (age, size, soil, spatial context, previous land use and a special focus on vegetation) and management characteristics of 23 projects in the food forest movement in Flanders, Belgium. The projects differed substantially in almost every aspect, but we also discerned shared characteristics that largely correspond to how temperate food forests are commonly described and distinguish them from other food production systems in the region: the food forests harboured a high plant diversity and structural complexity and were managed with minimal external inputs and a focus on natural processes for the system’s functioning. They were typically managed for the provisioning of multiple services in often complex organisational constructions with diversified business models, but most managers were not dependent on the food forest for their livelihoods. Managers focused more on realising food forests’ environmental and socio-cultural functions than food production, and temperate food forests’ role in a transition to sustainable food systems will depend on how issues outlined with respect to their food production and biodiversity function will be handled in the future.

Homegarden agroforestry conserves biodiversity in the agricultural landscape. Farmers manage traditional and improved homegarden agroforestry system to enhance their food security and income. However, socioeconomic factors and agroforestry systems may influence the species composition and diversity of homegarden agroforestry systems, and there is limited study to make this assertion. The effects of homegarden practices, homegarden size, homegarden age, and household wealth status on plant diversity were investigated in southeast Ethiopia. Households’ homegardens were selected using a multistage sampling procedure. The Dello Mena and Harena Buluk districts in southeastern Ethiopia were chosen for the study due to the presence of both traditional and improved homegarden practices. Data were collected from 96 homegardens, constituting 200 nested sample plots, a plot size 20 × 20 m for an inventory of trees and shrubs. Additionally, five sub-plots (each 1 m × 1 m) were taken from each main sample plot to account tree seedlings and herbaceous plants. We identified 128 plant species across the studied homegardens, representing 103 genera and 52 families. Both traditional and improved homegarden agroforestry practices shared 76 plant species. Homegarden practices and homegarden size had a positive and significant effect on the plant species composition, Shannon diversity index, and Margalef species richness (p < 0.05). In contrast, homegarden age and household wealth status had no significant influence. The Shannon diversity index and Margalef species richness in the improved homegarden were by 25.2% and 21.6% higher, respectively, than in the traditional homegarden. We concluded that the efforts to conserve plant species diversity in homegarden agroforestry should consider the homegarden practices and homegarden size to enhance biodiversity conservation in the agricultural landscape of the study region and beyond. The study will also serve as a showcase to identify the manageable socioeconomic factors and agroforestry systems that can enhance the conservation of plant diversity to support local livelihoods and foster various ecosystem services.

Traditional-homegardens are important for the food security, economy, and culture of rural communities, but also contributing to biodiversity conservation. The objective of this study was to evaluate the role of traditional-homegardens as a refuge for birds, how the birds used them, and which of their attributes were associated with the frequency of bird visits. We compared the percentage of visits among groups of birds by habitat preference. Also, we compared the frequency of visits to different vegetation strata and the use that birds made within traditional-homegardens (forage, perching or nesting). Finally, we analyzed the relationship between the number of visits and some characteristics of the traditional-homegardens (size area, richness of large plants and distance to the nearest forest fragment). Birds visited different vegetation stratum of traditional-homegardens to perch, to forage, and even to nest. In general, we found that larger traditional-homegardens area increased the number of bird visits, while distance to the native forest fragments and the species richness of large plants did not have significant effects. Insectivores and frugivores had a similar pattern to the general; to the granivores, the distance to the forest fragment had a positive effect on the number of visits; to the omnivores, the species richness of large plants had negative effect, to the nectarivores, none of the variables had a significant effect. Overall, this study sheds light on the significance of traditional-homegardens not only for human communities but also for biodiversity conservation by providing valuable habitats for a variety of bird species.

The objective of this study was to evaluate the herbaceous aboveground biomass production (DM kg ha⁻¹), the woodland structure and greenhouse gas (GHG) emissions mitigation capacity of agroecosystems under silvopastoral use in the semi-arid region located at the southern part of the Argentinean Pampa region called Espinal Periestépico. Two contrasting vegetable covers (woody vs. herbaceous) were selected in three locations (Algarrobo, Villalonga, and Patagones) along a precipitation and vegetation gradient. We measured in each location/cover the biodiversity/size of woody species, soil water dynamics at different depths, and forage productivity, methane (CH₄) concentration profiles and potential oxidation rates of CH₄ in laboratory conditions at different soil layers. Tree density varied between 820 and 1088 individuals ha⁻¹, a higher value compared to previous national forest inventory data. The average aboveground biomass of forage species in woody and herbaceous cover was greater than non-forage ones. A different soil water dynamics were observed according to vegetable cover and soil depth. Finally, CH₄ oxidation rate revealed different patterns between locations and vegetable cover. The result highlight the importance of considering vegetation cover and water dynamics in the sustainable management of these systems, while recognizing their ecosystem services, especially their potential to mitigate greenhouse gas (GHG) emissions.

Ensuring double cropping, securing livelihood and restoring ecosystem are the major challenges under rain-fed smallholder farming situation. A study was undertaken during 2013–2021 for smallholders through integrating rain water harvesting, crops, trees and livestock to estimate the multiple benefits to farmers and ecosystem under rain-fed situation. One hectare rain-fed integrated farming system (IFS) model comprising of farm pond, food crops, fodder crops, agrihortipasture, silvipasture, boundary plantation and livestock was evaluated on-station for various ecosystem services potential (provisioning, supporting, regulating and cultural) and also promoted on-farm. The smallholder rain-fed integrated farming system (IFS) produced total 5926 kg ha⁻¹ chickpea equivalent yield and multiple provisioning services including grains, fruits, straw, green fodder, milk, meat, fuel-wood, etc. The model recorded 1327.4 US$ ha⁻¹ year⁻¹ net returns with 1.6 benefit cost ratio and resulted round-the-year supply of income (US$ 141 to 509 every month) to the farmer. It generated 204 man-days ha⁻¹ year⁻¹ employment. The regulating services resulted from the IFS were improved soil fertility (39 and 22% more soil organic carbon in 0–15 and 15–30 cm soil layer, respectively), better infiltration rate, higher carbon stock (31.5%) with 1.36 Mg ha⁻¹ year⁻¹carbon sequestration rate. The rain-fed IFS provided supporting ecosystem services in the form of improved soil biodiversity (earthworm and microbial count) and nutrient (41.4 kg N, 18.7 kg P and 33.2 kg K ha⁻¹ year⁻¹) and by-product recycling [8.16 tonnes farmyard manure (FYM) and 1.13 tonnes farm-compost] besides providing many cultural services. The results highlighted that synergistic integration of rain water harvesting-crops-trees-livestock provides multiple ecosystem services and benefits that leads to sustainable food systems under rain-fed agro-ecosystems.