Showing papers in "Agroforestry Systems in 2018"

Agroforestry for soil health

Abstract: Healthy soil is one of the most critical resources for the health and sustainability of ecosystems, including agroecosystems. Although the agroforestry community has long been convinced of the soil health benefits of agroforestry practices, many of such practices remain to be fully accepted by the mainstream agriculture community. Agroforestry, as a sustainable land management practice, has shown solid evidence of its role in improving soil quality and health based on at least four decades of data gathered from the world over. This thematic issue presents 28 papers that add further to the body of knowledge to reaffirm that agroforestry can improve the major measurable soil metrics that define soil health. Collectively, these papers show that agroforestry has the ability to (1) enrich soil organic carbon better than monocropping systems, (2) improve soil nutrient availability and soil fertility due to the presence of trees in the system, and (3) enhance soil microbial dynamics, which would positively influence soil health. It is imperative that agroforestry, as part of a multifunctional land-use strategy, should receive increased attention in our policy discussion for the future of soil and soil health.

Agroforestry systems of high nature and cultural value in Europe: provision of commercial goods and other ecosystem services

Abstract: Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game Some of the cultural value of these systems can also be captured through tourism and local events However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services

Temperate agroforestry research: considering multifunctional woody polycultures and the design of long-term field trials

Abstract: The many benefits of agroforestry are well-documented, from ecological functions such as biodiversity conservation and water quality improvement, to cultural functions including aesthetic value. In North American agroforestry, however, little emphasis has been placed on production capacity of the woody plants themselves, taking into account their ability to transform portions of the landscape from annual monoculture systems to diversified perennial systems capable of producing fruits, nuts, and timber products. In this paper, we introduce the concept of multifunctional woody polycultures (MWPs) and consider the design of long-term experimental trials for supporting research on agroforestry emphasizing tree crops. Critical aspects of long-term agroforestry experiments are summarized, and two existing well-documented research sites are presented as case studies. A new long-term agroforestry trial at the University of Illinois, “Agroforestry for Food,” is introduced as an experiment designed to test the performance of increasingly complex woody plant combinations in an alley cropping system with productive tree crops. This trial intends to address important themes of food security, climate change, multifunctionality, and applied solutions. The challenges of establishing, maintaining, and funding long-term agroforestry research trials are discussed.

How is agroforestry perceived in Europe? An assessment of positive and negative aspects by stakeholders

Abstract: Whilst the benefits of agroforestry are widely recognised in tropical latitudes few studies have assessed how agroforestry is perceived in temperate latitudes. This study evaluates how stakeholders and key actors including farmers, landowners, agricultural advisors, researchers and environmentalists perceive the implementation and expansion of agroforestry in Europe. Meetings were held with 30 stakeholder groups covering different agroforestry systems in 2014 in eleven EU countries (Denmark, France, Germany, Greece, Hungary, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom). In total 344 valid responses were received to a questionnaire where stakeholders were asked to rank the positive and negative aspects of implementing agroforestry in their region. Improved biodiversity and wildlife habitats, animal health and welfare, and landscape aesthetics were seen as the main positive aspects of agroforestry. By contrast, increased labour, complexity of work, management costs and administrative burden were seen as the most important negative aspects. Overall, improving the environmental value of agriculture was seen as the main benefit of agroforestry, whilst management and socio-economic issues were seen as the greatest barriers. The great variability in the opportunities and barriers of the systems suggests enhanced adoption of agroforestry across Europe will be most likely to occur with specific initiatives for each type of system.

Supporting and regulating ecosystem services in cacao agroforestry systems

Abstract: Cacao agroforestry systems (CAFS) can provide supporting services such as optimum light conditions for cacao growth, water and nutrient cycling and regulating services such as pest and disease control and climate regulation. This review considers recent literature on the manifestation of these services in CAFS around the world to provide an overview of scientific knowledge. Crown structures of associated trees can facilitate optimum light conditions for cacao growth, and provide water through vertical root segregation. Leaf litter fall and roots from associated species contribute to nutrient cycling. Both nitrogen-fixing and non-nitrogen-fixing species can provide nutrients to the cacao plant, though competition from certain species may limit phosphorus and potassium uptake. Pest and disease regulating services can arise through careful shade management to create a microclimate which reduces susceptibility of cacao to fungal diseases and sun-loving pests. All CAFS store carbon to varying degrees; those resembling original forest much more than simple two-species systems from which shade trees are removed after maturity of the cacao stand. CAFS also promotes biodiversity conservation depending on structure, management, and landscape arrangement, though not to the extent of natural forests. Research opportunities to increase provision of these services include optimal spatial arrangement for nutrient cycling and functional diversity as well as landscape connectivity for biodiversity conservation. Trade-offs between carbon storage, biodiversity, cacao yield and socio-economic resilience are presented, indicating that optimization of ecosystem services in CAFS requires consideration of interactions between all services, including socio-cultural and economic ones.

Farmers’ reasoning behind the uptake of agroforestry practices: evidence from multiple case-studies across Europe

Abstract: Potential benefits and costs of agroforestry practices have been analysed by experts, but few studies have captured farmers’ perspectives on why agroforestry might be adopted on a European scale. This study provides answers to this question, through an analysis of 183 farmer interviews in 14 case study systems in eight European countries. The study systems included high natural and cultural value agroforestry systems, silvoarable systems, high value tree systems, and silvopasture systems, as well as systems where no agroforestry practices were occurring. A mixed method approach combining quantitative and qualitative approaches was taken throughout the interviews. Narrative thematic data analysis was performed. Data collection proceeded until no new themes emerged. Within a given case study, i.e. the different systems in different European regions, this sampling was performed both for farmers who practice agroforestry and farmers who did not. Results point to a great diversity of agroforestry practices, although many of the farmers are not aware of the term or concept of agroforestry, despite implementing the practice in their own farms. While only a few farmers mentioned eligibility for direct payments in the CAP as the main reason to remove trees from their land, to avoid the reduction of the funded area, the tradition in the family or the region, learning from others, and increasing the diversification of products play the most important role in adopting or not agroforestry systems.

Advances in European agroforestry: results from the AGFORWARD project

Abstract: In global terms, European farms produce high yields of safe and high quality food but this depends on the use of many off-farm inputs and the associated greenhouse gas emissions, loss of soil nutrients and other negative environmental impacts incur substantial societal costs. Farmers in the European Union receive support through a Common Agricultural Policy (CAP) that comprises direct payments to farmers (Pillar I) and payments related to rural development measures (Pillar II). This paper examines the ways in which agroforestry can support European agriculture and rural development drawing on the conclusions of 23 papers presented in this Special Issue of Agroforestry Systems which have been produced during a 4-year research project called AGFORWARD. The project had the goal of promoting agroforestry in Europe and focused on four types of agroforestry: (1) existing systems of high nature and cultural value, and agroforestry for (2) high value tree, (3) arable, and (4) livestock systems. The project has advanced our understanding of the extent of agroforestry in Europe and of farmers’ perceptions of agroforestry, including the reasons for adoption or non-adoption. A participatory approach was used with over 40 stakeholder groups across Europe to test selected agroforestry innovations through field trials and experiments. Innovations included improved grazing management in agroforestry systems of high nature and cultural value and the introduction of nitrogen fixing plants in high value timber plantations and olive groves. Other innovations included shelter benefits for arable crops, and disease-control, nutrient-retention, and food diversification benefits from integrating trees in livestock enterprises. Biophysical and economic models have also been developed to predict the effect of different agroforestry designs on crop and tree production, and on carbon sequestration, nutrient loss and ecosystems services in general. These models help us to quantify the potential environmental benefits of agroforestry, relative to agriculture without trees. In view of the substantial area of European agroforestry and its wider societal and environmental benefits, the final policy papers in this Special Issue argue that agroforestry should play a more significant role in future versions of the CAP than it does at present.

Spatial similarities between European agroforestry systems and ecosystem services at the landscape scale

Abstract: Agroforestry systems are known to provide ecosystem services which differ in quantity and quality from conventional agricultural practices and could enhance rural landscapes. In this study we compared ecosystem services provision of agroforestry and non-agroforestry landscapes in case study regions from three European biogeographical regions: Mediterranean (montado and dehesa), Continental (orchards and wooded pasture) and Atlantic agroforestry systems (chestnut soutos and hedgerows systems). Seven ecosystem service indicators (two provisioning and five regulating services) were mapped, modelled and assessed. Clear variations in amount and provision of ecosystem services were found between different types of agroforestry systems. Nonetheless regulating ecosystems services were improved in all agroforestry landscapes, with reduced nitrate losses, higher carbon sequestration, reduced soil losses, higher functional biodiversity focussed on pollination and greater habitat diversity reflected in a high proportion of semi-natural habitats. The results for provisioning services were inconsistent. While the annual biomass yield and the groundwater recharge rate tended to be higher in agricultural landscapes without agroforestry systems, the total biomass stock was reduced. These broad relationships were observed within and across the case study regions regardless of the agroforestry type or biogeographical region. Overall our study underlines the positive influence of agroforestry systems on the supply of regulating services and their role to enhance landscape structure.

Agroforestry for high value tree systems in Europe

Abstract: Most farm-based agroforestry projects focus on the integration of trees on arable or livestock enterprises. This paper focuses on the integration of understorey crops and/or livestock within high value tree systems (e.g., apple orchards, olive groves, chestnut woodlands, and walnut plantations), and describes the components, structure, ecosystem services and economic value of ten case studies of this type of agroforestry across Europe. Although their ecological and socio-economic contexts vary, the systems share some common characteristics. The primary objective of the farmer is likely to remain the value of tree products like apples, olives, oranges, or nuts, or particularly high value timber. However there can still be production, environmental or economic benefits of integrating agricultural crops such as chickpeas and barley, or grazing an understorey grass crop with livestock. Three of the systems focused on the grazing of apple orchards with sheep in the UK and France. The introduction of sheep to apple orchards can minimise the need for mowing and provide an additional source of revenue. Throughout the Mediterranean, there is a need to improve the financial viability of olive groves. The case studies illustrate the possibility of intercropping traditional olive stands with chickpea in Greece, or the intercropping of wild asparagus in high density olive groves in Italy. Another system studied in Greece involves orange trees intercropped with chickpeas. Stands of chestnut trees in North-west Spain can provide feed for pigs when the fruit falls in November, and provide an excellent habitat for the commercial production of edible mushrooms. In Spain, in the production of high quality walnut trees using rotations of up to 50–60 years, there are options to establish a legume-based mixed pasture understorey and to introduce sheep to provide financial and environmental benefits.

Home garden system dynamics in Southern Ethiopia

Abstract: Home gardens in southern Ethiopia are regarded as efficient farming systems, allowing interactions and synergies between crop, tree and livestock components. However, these age-old traditional home gardens are evolving rapidly in response to changes in both the socio-economic and biophysical environment. Altered cropping patterns, farm size and component interactions may affect the systems’ sustainability. Home gardens exhibit a huge diversity in farms and farming systems, which needs to be understood in order to design interventions for improvement. Dynamics of home gardens were studied over two-decades (1991–2013) based on a survey of 240 farm households and focus group discussions. Farms were grouped into five types: Khat-based, Enset-cereal-vegetable, Enset-based, Enset-coffee and Enset-livestock. Farm trajectories revealed a shift from food-oriented Enset-based and Enset-livestock systems to (1) cash crop oriented khat-based systems, and (2) combined food and cash crop oriented Enset-cereal-vegetable systems. In densely populated, market proximate areas a major trend was expansion of khat, from 6 to 35% of the area share per farm, while the combined area share of enset and coffee decreased from 45 to 25%. Concurrently, the cattle herd size fell from 5.8 TLU to 3.9 TLU per household. In medium populated, less accessible areas the trend was consolidation of combined production of food and cash crops. Enset and coffee together maintained a share of over 45%. Easy transport and marketing of the perishable cash-generating khat compared with traditional crops favoured its cultivation among smallholders located close to markets. The insights in home garden change in response to increasing population pressure, decreasing farm size and market development may help to design interventions to increase system sustainability.

The contribution of non-timber forest products (NTFPs) to rural household revenues in two villages in south-eastern Burkina Faso

Abstract: Non-timber forest product (NTFP) providing species constitute substantial components of West African agroforestry systems and contribute considerably to local livelihoods. The aim of our study was to measure the annual economic contribution of NTFPs to local livelihoods in two villages of south-eastern Burkina Faso, focusing on the following specific questions: What is the average share of NTFPs in local household income? Which socio-economic variables affect total household income and NTFP dependency? How does NTFP income vary between (i) villages, (ii) ethnic groups and (iii) different income groups? Does NTFP income have an equalising effect on income inequality? Applying structured household surveys, we investigated the economic contribution of NTFPs household revenues among 155 households. NTFPs accounted for the second largest income share (45 %) of total household income compared to other income sources, i.e. crop production, livestock breeding and off-farm activities. We found that poorer households depend more on income from NTFPs than wealthier households, even though the latter earned more from NTFPs in absolute terms. In general, income from NTFPs had an equalising effect on income inequality. Furthermore, we discovered significant differences in NTFP dependency between the two investigated villages and across the three main ethnic groups (Gourmantche, Mossi, Fulani) reflecting different species compositions in their surroundings as well as different traditional uses and harvesting practices. Thus, we argue that management recommendations for agroforestry systems and poverty alleviation need to consider local differences with regard to site-specific species composition as well as ethnic-specific NTFP use patterns and habits.

A reliable and non-destructive method for estimating forage shrub cover and biomass in arid environments using digital vegetation charting technique

Abstract: Despite the importance of fodder shrubs to small ruminant diets and production in arid and semi-arid ecosystems, they are often not considered when quantifying grazing land potential. This oversight is mainly due to the time consuming and costly traditional techniques used to estimate shrub biomass. The shrub fodder component should be measured to avoid underestimation of the carrying capacity of rangelands. In this study, we present a fast, reliable and non-destructive method to estimate canopy vegetation cover to obtain aboveground shrub biomass. The experiment was conducted under field conditions in northwest Syria, where seedlings of seven shrub species were monitored for one year: Atriplex leucoclada (Moq.) Boiss., A. halimus L., A. lentiformis (Torr.) S. Watson, A. canescens (Pursh) Nutt., A. nummularia Lindl., Salsola vermiculata L. and Haloxylon aphyllum (C.A. Meyer) Bunge. The experimental layout was a randomized complete block design with five replications. We explored the effectiveness of digital vegetation charting technique (DVCT) for estimating shrub canopy cover. Aboveground shrub biomass was clipped to estimate the dry matter (DM) weight per species and to determine its relationship to canopy cover. In this study, an estimate of greenness (percent green vegetation cover) was extracted by way of greenness algorithms. Simple linear regressions between vegetation cover and biomass for 210 plots were performed. The cover of the seven species differed (P < 0.01): A. leucoclada had the highest vegetation cover (56%) and H. aphyllum the lowest (7%). Vegetation cover and DM biomass were positively correlated (P < 0.01) with R-squared ranging from 0.66 (H. aphyllum) to 0.84 (S. vermiculata). Our method provided reasonable estimations of canopy coverage which could predict aboveground phytomass. We conclude that DVCT offers a rapid, reliable and consistent measurement of shrub cover and biomass provided that shrubs have open architecture. This study shows the potential of digital cameras and image processing to determine cover/biomass in a non-destructive, timely and cost efficient way.

Rehabilitation practices that shape cocoa agroforestry systems in Central Cameroon: key management strategies for long-term exploitation

Abstract: In Africa’s main cocoa producing countries, rehabilitation of old cocoa orchards is increasingly debated but rarely adopted. In Central Cameroon, rehabilitation practices are regularly set up in old cocoa-based agroforestry systems (cAFS). To better understand the impact of such practices we built a chronosequence of 40 cAFS. We carried out specific surveys with farmers on each plot in order to check for rehabilitation effects on cocoa stands and associated woody species (AWS). We found that cocoa trees represented on average 88.2% of woody individuals and increased with age (from 84.7 to 91.5%). The cocoa stand basal area (BA) share significantly increased with age and reached up to 40.2% in the oldest systems. Cocoa, fruit and forest trees mean BA increased with aging. They were on average of 6.5, 5.7 and 10.7 m2 ha−1 respectively. Six different architectural types, different from the theoretical architectural evolution of cocoa trees over time, were identified. Among them, type 4 characterized by several orthotropic suckers of differing ages, was found typical of farmers’ cutting back practices. Type 4 cocoa trees density increased over time and its BA represented on average 60% of cocoa stand BA in the oldest systems. Concomitantly, farmer’s management of AWS led to continuous evolution of the systems both in terms of density and species composition. Our results show that (i) permanent densification and cutting back practices (type 4) allow the rejuvenation of cocoa stands while increasing cocoa stands BA share; (ii) the continuous management of AWS by farmers is undertaken to favour cocoa trees share over time by limiting inter-specific competition and promoting complementarity between cocoa trees and AWS. We argue that such practices explain a fair part of the long-term sustainability observed in cAFS from Central Cameroon and represent a model from which new rehabilitation schemes could be inspired.

Yield components and phenology of durum wheat in a Mediterranean alley-cropping system

Abstract: It is often claimed that agroforestry could increase the total productivity per land unit compared to monocropping systems. The aim of this study was to evaluate, in a sub-humid Mediterranean climate, the behavior of the yield components, phenology, LAI and NDVI of durum wheat in an alley-cropping system. Our hypothesis was that the microclimate changes in agroforestry could change the devlelopment and yield of cereals. Two different experiments were carried out: in 2015 under 16-year old poplars in East–West lines and in 2016 under 21-year-old ash trees in North–South lines. In each experiment, 12 genotypes of durum wheat were sown. The grain yield was not significantly different in agroforestry and full sun conditions in 2015; however, both systems in this experiment had a particularly low yield (≈ 10% of the historical average yield of the plot). In 2016, the grain yield was significantly lower in agroforestry in comparison with full sun conditions. In both experiments, the most impacted yield component by agroforestry was the number of grains per spike. Similarly, in both experiments, the number of grains per spike was the only yield component impacted by the position within the alley inside agroforestry. Surprisingly, in 2016 the grain yield was higher in the West than in the center position of the alley. In both experiments, agroforestry delayed the maturity of the crop. The use of standard growing degree days was not sufficient to explain the difference in phenology between agroforestry and full sun conditions.

Modelling and valuing the environmental impacts of arable, forestry and agroforestry systems: a case study

Abstract: The use of land for intensive arable production in Europe is associated with a range of externalities that typically impose costs on third parties. The introduction of trees in arable systems can potentially be used to reduce these costs. This paper assesses the profitability and environmental externalities of a silvoarable agroforestry system, and compares this with the profitability and environmental externalities from an arable system and a forestry system. A silvoarable experimental plot of poplar trees planted in 1992 in Bedfordshire, Eastern England, was used as a case study. The Yield-SAFE model was used to simulate the growth and yields of the silvoarable, arable, and forestry land uses along with the associated environmental externalities, including carbon sequestration, greenhouse gas emissions, nitrogen and phosphorus surplus, and soil erosion losses by water. The Farm-SAFE model was then used to quantify the monetary value of these effects. The study assesses both the financial profitability from a farmer perspective and the economic benefit from a societal perspective. The arable option was the most financially profitable system followed by the silvoarable system and forestry. However, when the environmental externalities were included, silvoarable agroforestry provided the greatest benefit. This suggests that the appropriate integration of trees in arable land can provide greater well-being benefits to society overall, than arable farming without trees, or forestry systems on their own.

The contribution of NTFP-gathering to rural people’s livelihoods around two timber concessions in Gabon

Abstract: NTFPs are often presented as a major contributor to livelihoods, as sources of food and cash, particularly for rural communities. There are few data available in Gabon to confirm this common assertion. This study was conducted on 127 households in 14 villages around two timber concessions in the south-eastern and south-western regions of Gabon for a period of one year. Conventional socio‐economic survey tools such as focus group discussions, census and semi-structured interviews with households were used for gathering the data. Results reveal that rural people depend on various sources of food and income for their livelihoods, but overall, the current contribution of NTFPs obtained from plant sources is insignificant compared to those from other activities. Odika (Irvingia gabonensis), ‘atanga sauvage’ (Dacryodes buettneri), fungus (Termitomyces spp.) and Gabon nut (Coula edulis) represent the main forest products commonly harvested by rural people. They are used primarily for subsistence, but the surplus is sold. The results of this study suggest that: (1) the main components of decree No. 137/PR/MEFP of February 4, 2009, that prohibits the logging of five multiple-use tree species over a period of 25 years in order to safeguard the sources of NTFPs, should be reviewed; and (2) state authorities and partners should promote projects aimed at increasing public awareness of the NTFP sector. These projects should include a census of NTFPs (for food, for medicine and for services), characterize their uses and identify the markets of target products as well as the development potential of NTFPs. Such projects could help Gabon and other Congo Basin countries to fix norms/standards for sustainable natural resource management and for enhancing the contribution of NTFPs to the national economy. This will be particularly relevant in the wake of dwindling oil revenues and the need to diversify and promote other revenue sources in the country.

Influence of latitude on the light availability for intercrops in an agroforestry alley-cropping system

Abstract: Light competition by trees is often regarded as a major limiting factor for crops in alley-cropping agroforestry. Northern latitude farmers are usually reluctant to adopt agroforestry as they fear that light competition will be fiercer in their conditions. We questioned the light availability for crops in alley-cropping at different latitudes from the tropic circle to the polar circle with a process-based 3D model of alley-cropping agroforestry. Two tree densities and two tree line orientations were considered. The effect of the latitude was evaluated with same-sized trees. The relative irradiance of the crops was computed for the whole year or at specific times of the year when crops need more light. The heterogeneity of crop irradiance across the alley was also computed. Surprisingly, crop relative irradiance of summer crops at high latitudes is high, at odds with farmers’ fears. Best designs were highlighted for improving the crop irradiance: North–South tree lines are recommended at high latitudes and East–West tree lines at low latitudes. At medium latitudes, North–South tree lines should be preferred to achieve an homogeneous irradiance of the crop in the alley. If we assume that trees at northern latitudes grow slower when compared to southern latitudes, then alley-cropping agroforestry is highly advisable even at high latitudes with summer crops.

What is good about Sri Lankan homegardens with regards to food security? A synthesis of the current scientific knowledge of a multifunctional land-use system

Abstract: Recently, there has been growing interest in agroforestry systems due to their great potential to mitigate threats to household food and nutrition security from soaring food prices but also as carbon sinks In Sri Lanka, smallholder farms such as homegardens constitute a majority of Sri Lanka’s total annual crop and timber production Despite Sri Lankan homegardens being considered desirable and sustainable land-use systems, their role in food and nutrition security is not yet entirely understood By synthesising scientific articles and grey literature we sought the link between food security and homegardens by quantifying their products or services and ascertaining whether food security characteristics are assessed as direct or indirect impacts The results show that 27% of 92 identified articles directly quantified aspects that are relevant to food security Another 51% of the articles quantified indirect aspects that have relevance for food security, including climate, soil, ecosystem services, structural and floristic diversity and economic aspects Twenty-two percent of the articles were categorised as being qualitative or conceptual and contained no direct assessments or quantification of food security The presence of significant merits from homegardens includes providing food security throughout the year at low-cost while sustaining numerous ecosystem services This benefits particularly the poor farmers However, many studies are descriptive and only provide location-specific information on single research focuses such as plant species, yield and management There are few comparisons with crop land, forests or other production systems, and there is even less empirical evidence and quantification of the food security and other benefits Seven areas where more scientific focus would be beneficial are identified Homegardens are strong in national policies and to reach a greater level of efficiency within these activities our findings suggest more emphasis on a higher degree of inclusiveness of relevant stakeholders and long-term engagements with context specific guidance

Identifying barriers and motivators for adoption of multifunctional perennial cropping systems by landowners in the Upper Sangamon River Watershed, Illinois

Abstract: The demand on agriculture to meet food security goals and mitigate environmental impacts requires multifunctional land-use strategies. Considering both farmer motivations and rural development needs, one option is to transition marginal farmland to perennial crops. In this study, we considered the potential for Multifunctional Perennial Cropping Systems (MPCs) that would simultaneously provide production and ecosystem service benefits. We examined adoption potential of MPCs on marginal farmland through an agricultural landowner survey in the Upper Sangamon River Watershed in Illinois, USA. We identified adoption preferences among landowners in conjunction with socio-demographic characteristics that would facilitate targeted implementation. Hierarchical cluster analysis and discriminant analysis identified landowner categories and key factors affecting adoption potential. Landowner age, appreciation for plant diversity, and future farm management involvement were the strongest predictors of potential MPCs adoption. The landowner categories identified within the survey data, supplemented with focus group discussions, suggested a high adoption potential farmer profile as a young, educated landowner with known marginal land they would consider converting to MPCs for improved soil and water quality conservation.

Constraints for future cocoa production in Ghana

Abstract: To address the growing global demand for cocoa, sustainable intensification of its production in West Africa is considered crucial. This paper analyzes the determinants of cocoa productivity and profitability by smallholder farmers in Ghana to provide insights into challenges for future cocoa farming, which will guide the formulation and prioritization of tailored policies to address them. A four-stage sampling technique was used to select a total of 731 cocoa farmers from various districts in all six cocoa growing regions in Ghana. Selected farmers were interviewed using a semi-structured questionnaire. The results show that cocoa productivity and profitability was very low with an average of 234 kg ha−1 and Gh¢ 568 (ca. US$ 150) per ha, respectively. Farm management practices, namely control of capsid and black pod disease, fertilizer application and pruning, significantly (p < 0.05) influenced cocoa productivity. Capsid control and fertilizer application showed the highest impact on productivity. Farm size, however, had a negative impact, which implies that increase in farm size results in decreased smallholder cocoa productivity. Farmers should be encouraged to sustainably intensify farm management through controlling black pod disease and capsids, regular pruning and efficient application of fertilizer rather than focusing on excessive land expansion, which eventually hampers productivity and biodiversity.

Thermal comfort indices assessed in integrated production systems in the Brazilian savannah.

Abstract: The objective was to evaluate the animal thermal comfort indices from two integrated crop-livestock-forestry (ICLF) systems. For this, temperature–humidity index (THI), black globe temperature and humidity index (BGHI), and the radiant thermal load (RTL) were assessed. Two ICLF (ICLF-1 and ICLF-2) systems and one control system were established. On the ICLF systems, the arboreal component was the eucalyptus tree (Eucalyptus grandis × Eucalyptus urophylla; H13 clone), planted in simple wide-spaced rows. The ICLF-1 system had a tree spacing of 14 × 2 m with 357 trees per hectare, and the ICLF-2 had a tree spacing of 22 × 2 m with 227 trees per hectare. The control system had five scattered native trees per hectare, pertaining to Gochnatia and Dipteryx species. The forage component in all three systems was piata-grass (Brachiaria brizantha cv. BRS Piata). The experimental design was a randomized block in a sub-subplot design scheme with four replications. The presence of shade provided by the trees offered better conditions of animal comfort when compared with the condition of full sun. The ICLF-1 system, with higher tree density, provided better indicators for thermal comfort, THI, BGHI, and RTL when compared with the condition of full sun, while ICLF-2 was no different than ICLF-1 for BGHI.

Adaptation factors and futures of agroforestry systems in Nepal

Abstract: Farmers in Nepal mid-hills have practiced agroforestry for generations as main source or supplement of timber, firewood and fodder from government forests. The nature and extent of agroforestry practice is being challenged by rapid social and economic change particularly in the recent rise of labour out-migration and remittance income. Understanding is required of the critical factors that influence farmers in the way they adapt agroforestry to their circumstances. This paper analyses the relationship of households’ livelihood resources and agroforestry practice to identify trajectories of agroforestry adaptation to improve livelihood outcomes. Using data from a survey of 668 households, it was found that landholding, livestock holding and geographic location of farmers are key drivers for agroforestry adaptation. A multinomial logistic regression model showed that in addition to these variables, household income, household-remittance situation (whether the household is receiving remittance or not) and caste influence adaptation of agroforestry practice. The analysis indicates that resource-poor households are more likely to adapt to terraced-based agroforestry while resource-rich households adapt to woodlot agroforestry. Appropriate agroforestry interventions are: (1) develop simple silvicultural regimes to improve the quality and productivity of naturally-regenerating timber on under-utilised land; (2) develop a suite of tree and groundcover species that can be readily integrated within existing terrace-riser agroforestry practices; (3) acknowledge the different livelihood capitals of resource-poor and resource-rich groups and promote terrace-riser and woodlot agroforestry systems respectively to these groups; and (4) develop high-value fodder production systems on terrace-riser agroforestry, and also for non-arable land. The analysis generates important insights for improving agroforestry policies and practices in Nepal and in many developing countries.

Addressing farmer-perceptions and legal constraints to promote agroforestry in Germany

Abstract: Agroforestry is receiving increasing attention in Germany because of its capacity to address some of the negative consequences of intensive agriculture. However the actual uptake and maintenance of agroforestry by farmers remains low. The aim of this study was to identify the opportunities and obstacles to agroforestry in Germany and to identify potential measures which could address the obstacles and increase agroforestry adoption. Qualitative interviews with 32 farmers indicated that the legal framework and administrative burden associated with agroforestry in Germany was a major obstacle. The farmers recognised that agroforestry provided environmental benefits, but these do not always increase farm profitability. Agroforestry was identified as a viable alternative to conventional farming systems, especially in less productive areas, not profitable when managed in a conventional way. To enhance the implementation of agroforestry the simplification of the legal framework is crucial. Modern agroforestry should be better recognized by existing policy measures providing payments for environmentally friendly farming. Ultimately, an integrated approach for environmental benefits and production objectives is required, which is based on rewarding farmers for providing ecosystem services (ESs) and a stronger public involvement in sustainable land use practices. Rewarding farmers for ESs could increase the interest in agroforestry in highly productive areas, enhancing sustainable land use in the long term.

Shade trees: a determinant to the relative success of organic versus conventional coffee production

Abstract: Greater understanding of the influences on long-term coffee productivity are needed to develop systems that are profitable, while maximizing ecosystem services and lowering negative environmental impacts. We examine a long-term experiment (15 years) established in Costa Rica in 2000 and compare intensive conventional (IC) coffee production under full sun with 19 agroforestry systems combining timber and service tree species with contrasting characteristics, with conventional and organic managements of different intensities. We assessed productivity through coffee yield and coffee morphological characteristics. IC had the highest productivity but had the highest yield bienniality; in the agroforestry systems productivity was similar for moderate conventional (MC) and intensive organic (IO) treatments (yield 5.3 vs 5.0 t/ha/year). Significantly lower yields were observed under shade than full sun, but coffee morphology was similar. Low input organic production (LO) declined to zero under the shade of the non-legume timber tree Terminalia amazonia but when legume tree species were chosen (Erythrina poepiggiana, Chloroleucon eurycyclum) LO coffee yield was not significantly different than for IO. For the first 6 years, coffee yield was higher under the shade of timber trees (Chloroleucon and Terminalia), while in the subsequent 7 years, Erythrina systems were more productive, presumably this is due to lower shade covers. If IC full sun plantations are not affordable or desired in the future, organic production is an interesting alternative with similar productivity to MC management and in LO systems incorporation of legume tree species is shown to be essential.

Potential of the APSIM model to simulate impacts of shading on maize productivity

Abstract: A number of agroforestry models have been developed to simulate growth outcomes based on the interactions between components of agroforestry systems. A major component of this interaction is the impact of shade from trees on crop growth and yield. Capability in the agricultural production systems simulator (APSIM) model to simulate the impacts of shading on crop performance could be particularly useful, as the model is already widely used to simulate agricultural crop production. To quantify and simulate the impacts of shading on maize performance without trees, a field experiment was conducted at Melkassa Agricultural Research Centre, Ethiopia. The treatments contained three levels of shading intensity that reduced incident radiation by 0 (control), 50 and 75% using shade cloth. Data from a similar field experiment at Machakos Research Station, Kenya, with 0, 25 and 50% shading were also used for simulation. APSIM adequately simulated maize grain yield (r2 = 0.97) and total above-ground biomass (r2 = 0.95) in the control and in the 50% treatments at Melkassa, and likewise in the control (r2 = 0.99), 25% (r2 = 0.90) and 50% (r2 = 0.98) treatments at Machakos. Similarly, APSIM effectively predicted Leaf Area Index attained at the flowering (r2 = 0.90) and maturity (r2 = 0.94) stages. However, APSIM under-estimated maize biomass and yield at 75% shading. In conclusion, the model can be reliably employed to simulate maize productivity in agroforestry systems with up to 50% shading, but caution is required at higher levels of shading.

Why do farmers still grow corn on steep slopes in northwest Vietnam

Abstract: Intense cultivation of annual crops on steep slopes in northwest Vietnam has resulted in widespread and severe erosion. This has led to myriad problems including siltation of dams critical for hydroelectricity generation, and increasing levels of rural poverty due to declining crop yields. The solution to these problems is sustainable land management, in particular sloping land agricultural technologies. Our study focuses on defining, and finding solutions to, a second-order problem: that farmers are reluctant to adopt sustainable land management practices, despite numerous projects demonstrating their effectiveness. Interviews with farmers in northwest Vietnam confirmed that intense corn cultivation on steep slopes provided the majority of income for most households. The financial security associated with growing corn (compared to alternative crops) was the deciding factor in land management choices. However, interviews also revealed that farmers were dissatisfied with growing corn because of low income and high input costs. Farmers’ replies indicated that they thought they had no alternative to growing corn. However, farmers were aware of alternative crops, and were particularly interested in growing grass, fruit trees and timber trees, although few farmers were keen to be first to adopt these alternative species extensively. Further research is required on development of production-to-commercialization chains for alternative crops, and more generally, to find ways to increase farmer financial security during transition to sustainable land management.

Land use change and soil carbon pools: evidence from a long-term silvopastoral experiment

Abstract: Multi-functional silvopastoral systems provide a wide range of services to human society including the regulation of nutrients and water in soils and the sequestration of atmospheric carbon dioxide (CO2) Although silvopastoral systems significantly contribute to enhance aboveground carbon (C) sequestration (eg C accumulation in woody plant biomass), their long-term effects on soil C pools are less clear In this study we performed soil physical fractionation analyses to quantify the C pool of different aggregate fractions across three land use types including (1) silvopastoral system with ash trees (Fraxinus excelsior L), (2) planted woodland with ash trees, and (3) permanent grassland, which were established in 1989 at Loughgall, Northern Ireland, UK Our results show that 26 years after the conversion of permanent grassland to either silvopastoral or woodland systems, soil C (and N) stocks (0–20 cm depth) did not significantly change between the three land use types We found, however, that permanent grassland soils were associated with significantly higher C pools (g C kg−1 soil; P 2 mm) whereas soil C pools of the micro-aggregate (53–250 μm) and silt and clay (< 53 μm) fractions were significantly higher in the silvopastoral and woodland systems (P < 005) A key finding of this study is that while tree planting on permanent grassland may not contribute to greater soil C stocks it may, in the long-term, increase the C pool of more stable (recalcitrant) soil micro-aggregate and silt and clay fractions, which could be more resilient to environmental change

Global and European policies to foster agricultural sustainability: agroforestry

Abstract: Agroforestry is a sustainable land management system recognized worldwide but not implemented in a extensive form in temperate and developed countries. Agroforestry has been promoted in the last decades at global level as it provides more efficient and sustainable farming systems. This review aims at summarizing the main research findings explaining why agroforestry is a sustainable land management that fulfils and is affected by different Global, Pan-European and European policies as well as how innovation is currently fostered in Europe, therefore linking research, policy and innovation. This review specially targets researchers and policy makers working in integrated land systems. There is a global and European recognition of the role that agroforestry can play to provide products but also to deliver highly important ecosystem services. However, the promotion of agroforestry practices at European level is still not well addressed by the Common Agricultural Policy. The clear identification of agroforestry practices, the link of management plans to establish agroforestry pursuing a final eligible tree density for the Pillar I payments should be addressed as initial steps to foster agroforestry in Europe. There is a lack of knowledge transfer that promotes agroforestry at field level, which should be approached by using stakeholder integration within the policy development as it is currently done by the EIP-Agri.

Agroforestry in the European common agricultural policy

Abstract: Agroforestry is a sustainable land management system that should be more strongly promoted in Europe to ensure adequate ecosystem service provision in the old continent (Decision 529/2013) through the common agricultural policy (CAP). The promotion of the woody component in Europe can be appreciated in different sections of the CAP linked to Pillar I (direct payments and Greening) and Pillar II (rural development programs). However, agroforestry is not recognised as such in the CAP, with the exception of the Measure 8.2 of Pillar II. The lack of recognition of agroforestry practices within the different sections of the CAP reduces the impact of CAP activities by overlooking the optimum combinations that would maximise the productivity of land where agroforestry could be promoted, considering both the spatial and temporal scales.

How local stakeholders perceive agroforestry systems: an Italian perspective

Abstract: This paper reports the results of a study conducted in Italy, within the AGFORWARD (2014–2017) project, aimed at promoting innovative agroforestry practices in Europe Agroforestry offers a means for maintaining food production whilst addressing some of the negative environmental effects of intensive agriculture This study aims to elicit the positive and negative points of view and perceptions of local stakeholders in Italy in relation to three types of agroforestry systems The Participatory Research and Network Development was implemented in three workshops conducted in Sardinia, Umbria, and Veneto regions, and applied adopting a common methodological protocol Qualitative data were obtained using open discussions with stakeholders on key issues, challenges and innovations Quantitative data were obtained from stakeholders completing questionnaires during the workshops A statistical analysis was applied to elicit the differences in stakeholders’ positive and negative perceptions in relation to production, management, environment and socio-economy aspects Although the participants in the study came from different geographical and socioeconomic contexts with varied educational and cultural backgrounds, the different professional groups (farmers, policy-makers and researchers) and the three workshops generally shared similar perceptions of the benefits and constraints The effects of agroforestry on production and the environment were generally perceived as positive, whilst those related to management were generally negative The process of bringing the groups together seemed to be an effective means for identifying the key research gaps that need to be addressed in order to promote the uptake and maintenance of agroforestry