**Agroforestry: An Avenue for Resilient and Productive Farming through Integrated Crops and Livestock Production**

**Nuwandhya S. Dissanayaka, Shashi S. Udumann, Tharindu D. Nuwarapaksha and Anjana J. Atapattu**

#### **1. Introduction**

The global population is expected to reach approximately 9.7 billion by 2050, presenting a significant challenge in terms of ensuring food security and eradicating hunger on a global scale (Lal 2016). Worldwide scientific research engagement and highlighting the importance of providing sufficient, safe, and nutritious food for the growing population are essential to addressing this challenge. Sustainable Development Goal 2 (SDG 2) states that zero hunger and food security are multidimensional concepts that encompass the availability, access, utilization, and the stability of food supplies to meet the dietary requirements of individuals (FAO 2022). Achieving zero hunger implies ensuring that every person has access to an adequate quantity of safe, nutritious, and culturally appropriate food.

Resilience, in the context of agriculture, denotes the ability of farms, farmers, and farming systems to foresee future challenges, withstand external pressures, and adjust in response to various stresses, using unexpected climate changes as well as trade, financial, and policy-related mechanisms (Mathijs and Wauters 2020). A productive farming system refers to an agricultural approach or method designed and managed to optimize the output of crops, livestock, or other agricultural products. It focuses on maximizing the efficiency of resource utilization, including land, water, nutrients, and labor, to ensure high yields and sustainable production. Resilient and productive farming with agroforestry practices plays a vital role in accomplishing this objective more versatilely (Dissanayaka et al. 2023). Agroforestry is a complex and intricate land use system that combines different tree elements, seasonal crops, and/or animal components (Sarvade and Singh 2014). It aims to achieve a range of environmental, social, and economic advantages in every part of the world (Dhyani et al. 2021; Octavia et al. 2022). The resilience of the agroforestry farming system can be assessed by addressing the following points: (1) the resilience of what, by characterizing the farming system; (2) resilience to what, by identifying economic, environmental, social, and institutional challenges; (3) resilience for what purpose, by

identifying desired functions of the farming system; (4) what the resilience capacities are, by assessing resilience capacities; and (5) what enhances resilience, by assessing resilience-enhancing attributes (Meuwissen et al. 2019).

The objective of this review is to provide an overview and evaluate the role of agroforestry in enhancing agricultural resilience and productivity. Specifically, the review aims to carry out the following:


#### **2. Di**ff**erent Types of Agroforestry Systems**

Considering the spatial and temporal arrangement of its components, agroforestry systems can be categorized into three main systems: agri-silvicultural systems, silvo-pastoral systems, and agro-silvi-pastoral systems (Nair et al. 2021).

Agri-silvi-cultural systems involve the intentional integration of crops and trees within the same farming landscape (Figure 1a) (Nair et al. 2021). The trees can be fruit trees, timber trees, or other commercially viable tree species. The agricultural component may include food crops, cash crops, medicinal plants, and mushrooms and is popular as a low-input production system (Atangana et al. 2014a). The integration of agriculture and forestry components allows for complementary interactions and synergies. Intercropping, alley cropping, shifting cultivation, chena, taungya, home gardening, plantation crop combinations, trees for conservation, shelter belts, windbreak, and live hedges can be identified as examples of this cropping system (Ayyam et al. 2019).

The silvo-pastoral systems are an integrated form of land use that combines trees, forage/pasture crops, and/or livestock grazing (Figure 1b) (Nair et al. 2021). They involve the deliberate and simultaneous management of trees and pasture for the production of food, timber, forage, and livestock. Fodder production is the main productive function in this system and needs a comparatively higher involvement of socio-economic and management than agri-silvicultural systems do (Atangana et al. 2014a). Silvo-pastoral systems can provide multiple benefits, including improved animal welfare, increased productivity, enhanced environmental sustainability, and

economic advantages. Silvi-pastures, horti-pastoral patures, trees on rangelands, plantation crops with pastures, protein banks, and seasonal forestry grazing can be categorized under this system (Ayyam et al. 2019; Dhyani et al. 2021).

Agro-silvi-pastoral systems integrate crops, trees, and livestock within the same farming landscape (Figure 1c) (Nair et al. 2021). The agricultural component may include food crops, cash crops, or forage crops for livestock. The tree component may include multipurpose trees. As a livestock component, cattle, buffaloes, swine, goat, sheep, and poultry farming are incorporated into the system. The integration of these components allows for complementary interactions and synergies between agriculture, silviculture, and livestock production. This system requires high human involvement for success.

Furthermore, apiculture with trees (integrating trees with bee-keeping) (Figure 1d) and aqua forestry (integrating trees with fish) are also common in some areas of the world, especially in highland sub-humid tropical areas (Ayyam et al. 2019). Agri-silvi-cultural systems are primarily suited for lowland humid tropical environments, while silvo-pastoral and agro-silvi-pastoral systems are more apt for highland humid tropics above 1200 m from sea level and lowland sub-humid tropical climates, respectively (Atangana et al. 2014a). Agri-silvi-pastoral, agro-pastoral, and silvo-pastoral systems are mostly prevalent in parts of Africa, Asia, and the Americas, whereas some gardens are widely practiced in South and Southeast Asia (Mahmud et al. 2021). In temperate zones, silvo-pastoral systems with coniferous trees and livestock are the most prevalent type of agroforestry system (Den Herder et al. 2017). Other than that, native agroforestry systems such as forests and woodlots and mesquite-based systems in North america, nomadic systems in South America, silvi-arable systems in temperate zones in China, and Dehesa systems in europe are some of the common agroforestry systems which can be seen in temperate zones in the world except shelter belts, windbreaks, riparian forest systems, intercropping, and allycropping systems (Bhardwaj et al. 2017).

**Figure 1.** Different agroforestry systems: (**a**) agri-silvicultural systems; (**b**) silvo-pastoral system; (**c**) agro-silvi-pastoral systems; (**d**) apiculture. Source: Figure by authors.

#### **3. Potential Benefits from Agroforestry Farming**

#### *3.1. Biodiversity and Ecosystem Services*

Agroforestry systems play a vital role in promoting biodiversity within agricultural landscapes, leading to enhanced resilience and productivity (Octavia et al. 2022; Udawatta et al. 2019). High biodiversity with the presence of diverse plant species, including trees, crops, and understory vegetation, creates a complex habitat that supports a wide range of plant and animal species (Rahman et al. 2023). The presence of diverse plant species in agroforestry systems attracts a greater variety of beneficial insects, birds, and other predators that act as natural enemies of pests (Rahman et al. 2023; Suroso et al. 2023). These beneficial organisms contribute to pest control by preying on or parasitizing pests, reducing the need for synthetic pesticides (Fahad et al. 2022; Jose 2009). For example, trees in agroforestry systems can provide shelter and food sources for predatory insects, such as ladybugs, lacewings, and

parasitic wasps, which help control crop pests. Agroforestry systems, with their various plant communities, support a broader range of pollinators, including bees, butterflies, birds, and bats (Udawatta et al. 2019). These pollinators play a crucial role in the reproductive success of both crops and wild plant species, contributing to higher yields and improved fruit sets (Bentrup et al. 2019; Centeno-Alvarado et al. 2023; Klein et al. 2003). The presence of flowering trees and shrubs in agroforestry systems provides additional nectar and pollen sources for pollinators, increasing their abundance and diversity (Lee-Mader et al. 2020). Trees in agroforestry systems contribute to an excellent biodiversity corridor by providing interconnected and ecologically diverse habitats that facilitate wildlife movement between fragmented landscapes (Haggar et al. 2019). As an overall effect, this system increases food security and food diversification.

#### *3.2. Nutrient Cycling and Soil Health*

Agroforestry systems improve nutrient cycling and soil health through various mechanisms (Atapattu et al. 2017; Dissanayaka et al. 2023). The leaf litter from trees, along with the decomposition of organic matter from different plant species, contributes to increased soil organic matter content. This organic matter enhances soil structure, water holding capacity, nutrient availability, and microbial activity (Mohammadi et al. 2011). The diverse root systems of trees and crops in agroforestry systems facilitate nutrient uptake from different soil depths, reducing nutrient leaching and enhancing nutrient cycling within the ecosystem (Hugenschmidt and Kay 2023). Furthermore, the diverse root systems of trees, along with the associated mycorrhizal networks, where tree roots form symbiotic relationships with beneficial fungi, increase nutrient availability for surrounding crops and improve crop productivity. They interact with the soil biological and chemical properties to extract and redistribute water in ways that remove pollutants from the contaminated soils over time through methods like decontamination, hyperaccumulation, and hydraulic lift (Table 1) (Atangana et al. 2014b; François et al. 2023). Root exudates from trees contain organic compounds that fuel microbial populations in the rhizosphere, promoting nutrient transformations and facilitating nutrient availability to plants (Beule et al. 2022).


**Table 1.** The ability of various agroforestry systems to reduce soil pollution levels.

Source: Table by authors.

The presence of trees and diverse vegetation in agroforestry systems improves water infiltration rates and helps control soil erosion (Fahad et al. 2022). The tree canopy intercepts rainfall, reducing the impact of raindrops on the soil surface and minimizing erosion. The deep roots of trees contribute to improved soil structure and porosity, enhancing water infiltration and reducing surface runoff (Jinger et al. 2022). Agroforestry systems thus mitigate the risk of soil erosion, especially during heavy rainfall events, helping to maintain soil fertility and prevent nutrient loss.

Nitrogen-fixing plants play a significant role in agroforestry systems by enriching the soil with nitrogen, a vital nutrient for plant growth (Sarvade and Singh 2014; Thomas et al. 2018). These plants have the unique ability to convert atmospheric nitrogen gas into a usable form through a symbiotic relationship with nitrogen-fixing bacteria and are genetically determined (Table 2) (Suzaki et al. 2015). These bacteria possess the enzyme nitrogenase, which enables them to convert atmospheric nitrogen (N2) into ammonia (NH3) through a process known as nitrogen fixation (Hoffman

et al. 2014). The ammonia is then converted into forms such as ammonium (NH<sup>4</sup> +) that can be utilized by plants. As a result, the presence of nitrogen-fixing plants improves the overall nitrogen availability in the soil, supporting the growth and productivity of neighboring plants.


**Table 2.** Nitrogen-fixing plant species and its nitrogen-fixing potential.

Source: Authors' compilation based on data from Adams et al. (2010); Muoni et al. (2020); Nuwarapaksha et al. (2023); Sarvade et al. (2014); Sharma et al. (2022).

#### *3.3. Livelihoods and Economic Benefits*

Agroforestry systems provide a wide range of products that can be harvested and sold, diversifying income streams for farmers. These products include timber from trees, fruits and nuts from fruit trees, fodder for livestock, livestock products (ex: meat, milk, and wool), and various non-timber forest products such as medicinal plants, honey, and bamboo (Kuyah et al. 2020; Tsegaye 2023). The diversity of products allows farmers to access multiple markets and income sources, reducing their dependence on a single crop or commodity. Agroforestry has demonstrated its potential for poverty reduction and creating sustainable economic opportunities, particularly in rural areas. By diversifying income sources and providing multiple products, agroforestry systems can increase the resilience of farming communities and

reduce their vulnerability to market fluctuations. Agroforestry also offers long-term benefits by enhancing soil fertility, reducing erosion, and promoting sustainable land management practices, ensuring the productivity and economic viability of farming systems over time (Dissanayaka et al. 2023).

#### *3.4. Climate Resilience and Adaptation*

Trees in agroforestry systems provide shade and act as windbreaks, offering protection to crops and livestock (Santoro et al. 2020; Smith et al. 2021). During heatwaves or periods of high temperatures, the shade provided by trees can reduce heat stress in crops and animals, mitigating potential yield losses and negative impacts on livestock health (Ramil Brick et al. 2022). Furthermore, the presence of trees modifies the microclimate by creating more favorable conditions, such as reduced temperature fluctuations and increased humidity, within the agroforestry system (Rosenstock et al. 2019). For example, the jackfruit-based agroforestry system reported a 3.37–9.25% reduction in soil temperature in Bangladesh (Riyadh et al. 2018). Agroforestry systems contribute to climate change adaptation by sequestering carbon dioxide (CO2) from the atmosphere, thereby mitigating greenhouse gas emissions (Chavan et al. 2021). Trees can capture and store carbon in their biomass and soil, acting as "carbon sinks". Differences in growth rates, wood densities, and lifespans are key factors influencing a tree's carbon storage capacity (Sharma et al. 2016). Certain tree species exhibit rapid growth, accumulating biomass swiftly, whereas others grow slowly but boast denser wood, leading to greater long-term carbon storage (Kaul et al. 2010). Agroforestry systems, with their tree components, can sequester significant amounts of carbon over time, thus helping to offset emissions and mitigate climate change (Table 3).


**Table 3.** Carbon storage potential of different agroforestry systems in different regions of the world.

\* Carbon storage values were standardized to a 50-year rotation. Source: Authors' compilation based on data from Albrecht and Kandji (2003).

#### **4. Factors to Consider**

The implementation of agroforestry involves several key steps to ensure the successful establishment and management of the system. While the specific steps may vary depending on the context and objectives, the following considerations are the main steps commonly involved in agroforestry implementation.

#### *4.1. Site Selection and Planning*

The first step is to identify suitable sites for agroforestry implementation. Site assessment helps determine the compatibility of tree species, crops, and livestock in a specific area. Planning involves determining the appropriate design, layout, and arrangement of the agroforestry system to maximize benefits and minimize potential conflicts. The design and layout should be adapted to the agroecological region and should be easy to manage. Chuma et al. (2021) and Nath et al. (2021) found the importance of basic parameters including climate, elevation, soil, aspects, slope orientation, euclidean distance to the road, euclidean distance to a river, and euclidean distance to the town while implementing agroforestry systems. Among them, sunlight availability, the direction of wind, precipitation frequency and amount, and irrigation water availability should be prioritized (De Zoysa 2022).

#### *4.2. Component Selection*

Selecting suitable animal, tree, and crop species is crucial for the success of the agroforestry system. The selection should consider local conditions, market demand, ecological requirements, and compatibility with other components (Banyal et al. 2018). It is important to choose tree and livestock species that are well adapted to the climate, water, and light contents, have economic value, and provide ecosystem services (Nerlich et al. 2013). Those species should be compatible with the tree species and meet the specific objectives of the system (De Zoysa 2022).

#### *4.3. Planting and Establishment*

The next step involves planting and establishing the trees, crops, and any additional components of the system, such as forage or livestock. Proper planting techniques, including spacing, depth, and care, are essential for successful establishment. Adequate soil preparation, irrigation, and weed control measures should be implemented to promote plant growth and survival (Ngarava et al. 2022).

#### *4.4. Management and Maintenance*

Ongoing management and maintenance are crucial to increasing the health and productivity of the agroforestry system (Isaac et al. 2007). This includes practices such as pruning, thinning, pest and disease management, irrigation, and fertilization (Ngarava et al. 2022). Regular monitoring of the system helps identify any issues or adjustments needed to optimize performance and minimize potential conflicts between tree and crop components.

#### *4.5. Harvesting and Utilization*

The harvesting of tree products, such as timber, fruits, nuts, or non-timber forest products, and the utilization of crops and livestock occur at appropriate stages of growth and maturity. Proper harvesting techniques and post-harvest handling are important to maintain the quality and value of the products (Facheux et al. 2007). The utilization of harvested products may involve marketing, processing, or value addition activities.

#### **5. Challenges with Agroforestry**

Agroforestry systems can take many years to become fully productive, as woody perennials like trees and shrubs take time to establish and grow. This long payback period is a major limitation, as farmers do not see returns on their investment for

the first several years (Sagastuy and Krause 2019). During this establishment phase, agroforestry systems often produce less than conventional agricultural systems do, reducing yields and farm income in the short term (Sollen-Norrlin et al. 2020). Managing the complexity of agroforestry systems with their multiple components can be challenging, as can balancing the resource demands of all the components through competition for light, water, and nutrients (Sollen-Norrlin et al. 2020). Farmers require substantial knowledge and skills to successfully manage this complexity. However, technical assistance and guidance are often lacking, due to the limited research and extension support for agroforestry (Kiyani et al. 2017). The high diversity of plants in agroforestry systems can attract some pests, diseases, and weeds compared to those in simpler systems. The availability of alternate hosts and resources can allow pest populations to build up (Griffiths et al. 1998; Staton et al. 2022). Controlling these requires additional management efforts. There are also challenges in marketing the diverse mix of products from agroforestry systems compared to commodity crops. A lack of established supply chains and low consumer awareness limit market opportunities in many areas (Do et al. 2020). This marketing uncertainty increases the risks and limits the economic viability of agroforestry. Additional challenges like limited financial resources, labor, planting materials, extreme weather events, livestock damage, and fire risks can all undermine agroforestry success (Ajayi 2007). While agroforestry offers benefits, overcoming its limitations requires substantial knowledge, resources, and long-term commitment from farmers and supporting institutions. It is important to note that the significance of these challenges can vary substantially across different geographical regions and socio-economic contexts.

#### **6. To Improve the System**

This complex system can be scaled up for resilient and productive farming by expanding the adoption and implementation of agroforestry practices at larger scales.

#### *6.1. Proper Awareness and Knowledge Sharing*

Raising awareness about the benefits and potential of agroforestry is crucial (Buck et al. 2020; Musa et al. 2019). This involves disseminating information about successful agroforestry case studies, research findings, and best practices. For that, workshops, seminars, forum discussions, training, peer assistance or advice, film shows, and action reviews by experts, targeting farmers, agricultural communities, and local and foreign stakeholders can be organized with the help of universities, research stations, and other governmental and non-governmental organizations (Kommey and Fombad 2023). Agroforestry demonstration farms can be established

in different regions. These farms can showcase various agroforestry models, providing tangible examples of how agroforestry works and its benefits. Similarly, open days where farmers and the general public can visit these model farms can be arranged. Interactive sessions, guided tours, and hands-on experiences can significantly enhance understanding. Online platforms and resources can be maintained where farmers and communities can access knowledge and training on agroforestry techniques, management strategies, and potential income streams. Regularly updating these types of platforms with the latest news is necessary. In addition to that, monitoring and evaluation with continuous data collection and feedback loops will help to assess the needs and challenges faced by farmers practicing agroforestry and trading agroforestry products.

#### *6.2. Policy Support and Enabling Environment*

Supportive policies and institutional frameworks are essential for scaling up agroforestry (Dagar et al. 2020; Ndlovu and Borrass 2021). Governments and policymakers can create incentives, regulations, and programs that promote and facilitate agroforestry adoption (Xue 2023). This can include financial incentives, technical assistance, land tenure security, and favorable market conditions for agroforestry products (Buck et al. 2020). Collaboration among different government departments, such as agriculture, forestry, and environment, is critical for integrated policy support.

Access to finance and resources is crucial for farmers to adopt and scale up agroforestry practices (Foster and Neufeldt 2014; Simelton et al. 2017). Financial mechanisms, such as subsidies, grants, microfinance, and investment schemes, can be established to support agroforestry initiatives (Sagastuy and Krause 2019). Farmers also need access to quality planting material, technical support, and training. According to a survey conducted by Kareem et al. (2017) to determine the issues with agroforestry farming, the biggest problems in implementing agroforestry systems are insufficient capital, insufficient rainfall, land accessibility, an insufficient market center, a high cost of agro-chemicals, inaccessibility of tractors, and an instability of market price. Strengthening extension services and establishing nurseries or seed banks for agroforestry species can facilitate access to resources (Shah 2023).

Other than that, scaling up agroforestry requires a landscape-level approach, considering the spatial integration of agroforestry systems within larger farming landscapes and collaboration among various stakeholders, including farmers, researchers, government agencies, NGOs, and private sector actors. Suggestions of

**Figure 2.** Suggestions of the farmers in Musebeya sector, Nyamagabe District, in the southern province of Rwanda to improve the agroforestry systems. Source: Authors' compilation based on data from Kiyani et al. (2017).

#### **7. The Contribution of Agroforestry to Sustainable Development Goal 2**

As a holistic and sustainable agricultural approach, agroforestry plays a vital role in advancing the objectives of SDG 2 and moving toward a world with zero hunger (Montagnini and Metzel 2017). Diversified and nutritious food production with integrated crop and livestock management and the minimum addition of synthetic harmful agro-inputs fulfill the basic requirement of SDG 2, ensuring access to safe, nutritious, and sufficient food for all people (Duffy et al. 2021). Improved soil fertility and land productivity via promoting natural fertilization processes like legume cropping and high organic matter addition in the soil indirectly influence higher yields, which contribute to increased food availability (Fahad et al. 2022). Agroforestry systems are often more resilient to climate change due to their biodiversity and ability to conserve water. In the face of changing climate patterns, agroforestry provides a sustainable way to ensure food production, aligning with the goals of SDG 2, enhancing adaptive capacity against climate-related hazards and natural disasters (Mbow et al. 2014; Platis et al. 2019). In addition to that, agroforestry encourages local food production. When food is produced locally, there is often less waste associated with transportation and storage, contributing to the aim of reducing food loss and

waste. Importantly, agroforestry can provide additional sources of income through the sale of tree products, such as fruits, nuts, and timber (Beetz 2011; Kassie 2018). Increased income diversity for farmers improves their access to food and supports their ability to provide nutritious meals for their families. This sustainable land use system reduces soil erosion, conserves water, and protects biodiversity, contributing to the objective of SDG 2 on ensuring the sustainable use of terrestrial ecosystems.

#### **8. Conclusions**

In conclusion, resilient and productive farming is crucial to meeting the global challenge of ensuring food security for a growing population. Agroforestry practices play a vital role in achieving this objective by integrating trees, crops, and livestock in innovative and sustainable ways. Agroforestry systems can provide numerous benefits, including biodiversity conservation, nutrient cycling, soil health improvement, multiple income streams, climate resilience, and carbon sequestration. Through the integration of diverse components, such as agri-silvicultural, silvo-pastoral, and agro-silvi-pastoral systems, agroforestry can enhance agricultural productivity, support sustainable livelihoods, and contribute to ecological sustainability. Scaling up agroforestry requires raising awareness, policy support, access to finance and resources, landscape-level planning, and collaboration among stakeholders. By adopting and promoting agroforestry practices, it can foster resilient and productive farming systems that contribute to food security, poverty reduction, and sustainable development. Embracing agroforestry is not only a scientific solution but also an opportunity to create a more sustainable and inclusive future for agriculture.

**Author Contributions:** Conceptualization, N.S.D. and A.J.A.; methodology, S.S.U.; validation, A.J.A. and T.D.N.; formal analysis, N.S.D.; investigation, S.S.U.; writing—original draft preparation, N.S.D. and S.S.U.; writing—review and editing, A.J.A. and T.D.N.; supervision, A.J.A.; visualization, N.S.D. and S.S.U.; project administration, A.J.A. All authors contributed to the article and approved the submitted version.

**Funding:** This research received no external funding.

**Acknowledgments:** We would like to extend our gratitude to the technical team at the Agronomy Division of the Coconut Research Institute for their valuable contributions. We also want to express our thanks to the editor and two anonymous reviewers for providing constructive feedback and valuable comments.

**Conflicts of Interest:** The authors declare no conflict of interest.

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