The use of agroforestry crops is a promising tool for reducing atmospheric carbon dioxide concentration through fossil fuel substitution. In particular, plantations characterised by high yields such as short rotation forestry (SRF) are becoming popular worldwide for biomass production and their role acknowledged in the Kyoto Protocol. While their contribution to climate change mitigation is being investigated, the impact of climate change itself on growth and productivity of these plantations needs particular attention, since their management might need to be modified accordingly. Besides the benefits deriving from the establishment of millions of hectares of these plantations, there is a risk of increased release into the atmosphere of volatile organic compounds (VOC) emitted in large amounts by most of the species commonly used. These hydrocarbons are known to play a crucial role in tropospheric ozone formation. This might represent a negative feedback, especially in regions already characterized by elevated ozone level. Growth and management of agroforestry plantations will be influenced by climate change.

Developing strategies that counter the ongoing homogenization trends of home-garden agroforestry systems is required to maintain diversity and sustainability. This study aimed to map and characterize traditional enset-based home-garden agroforestry for managing sustainability in the Gurage socioecological landscape in Ethiopia. We generated plots and land use land cover (LULC) spatial data from orthophotomosaic and collected household survey data of the field. Five home-garden types were identified explicitly through integrating the home-garden composition, functional structure, and agroecological zones. Most home-garden types had similar horizontal functional structures in which perennial crops were planted close to homesteads, annual crops grew in outer fields, and woodlots were located at the end of the parcel. Diverse woody species, crop varieties, and plot sizes were identified in individual household parcels, and these varied across the home-garden types. Enset-based home-garden agroforestry production has been declining in the Ethiopian landscape because of socioeconomic changes and a lack of technological inputs. These challenges may compromise the community’s food security with loss of the product diversity provided by the home-garden system. Thus, technological adoptions and scaling up of agroforestry practices according to the home-garden types are necessary for the continue provision of multiple contributions. This study demonstrated site-specific spatial characterization of the agroforestry systems by considering a holistic approach to reduce the local challenges and support the development of sustainable landscape management in an altering socioecological landscape.

Information on biomass carbon storage in bamboo plantations/groves at local or regional landscapes is crucial to understand its potential in carbon stock management and climate change mitigation. The present work aims to study soil properties, litter dynamics and biomass carbon storage for the three common bamboo species from the Terai region of Indian Eastern Himalayas. Bambusa nutans, Dendrocalamus giganteus and Melocanna baccifera groves were selected for the present study. The soil pH, moisture and electrical conductivity under different bamboo groves of three species varied significantly, but moisture and electrical conductivity responded inconsistently with increasing soil depth. Similarly, the amount of soil available primary nutrients also varied significantly, where soils of M. baccifera grove were quantified with highest amount of these nutrients at all depths. M. baccifera grove produced the highest litter, although the difference with the other two groves was non-significant. The amount of oxidizable soil organic carbon quantified varied significantly among the bamboo groves, with the highest SOC content under the M. baccifera grove. The decomposition rate gradually increased with time, and within 9 months, the entire litter got decomposed. The annual return of nutrients was in the order N > K > P. The total biomass of D. giganteus, B. nutans and M. baccifera was estimated at 270.97, 127.21 and 16.31 Mg ha⁻¹, respectively. Based on the higher R² and adj R², and lower AIC and HQC, Model 1 was more appropriate for B. nutans and D. giganteus, whereas Model 2 was suitable for M. baccifera. The ecosystem carbon stock of D. giganteus was significantly (163.28 Mg ha⁻¹) higher than the other two species because of its significantly higher biomass carbon accumulation. This amount of biomass carbon storage and ecosystem carbon stock is comparable with agroforestry and forest ecosystems in the study region or elsewhere. The present study suggests these bamboos can be a feasible option for carbon farming and carbon trading, climate change adaptation and mitigation, apart from its contribution in social and economic contributions to the region’s rural life. Therefore, value addition and nationalizing of bamboo are recommended to improve rural folks’ livelihood. Encouraging value-added bamboo products can be negative feedback to climate change because of their durability and thus permanency of carbon stored in it.

Effective agroforestry diffusion under the newly started 10-Billion Trees Afforestation Project (10-BTAP) needs a thorough understanding of the policy and implementation shortfalls of the already completed BTAP. This study examines the factors that affected the diffusion of the agroforestry in the Hindu-Kush Himalayan (HKH) region of Pakistan under BTAP. The data were gathered through in-depth interviews with Village Development Committee (VDC) members, Forest Department (FD) officials, and local farmers. Important factors positively affecting agroforestry diffusion included locations of crop fields on the river sides, community dependency on firewood, and market value of agroforestry timber. The logistic regression model shows that household head’s age, access to information, and area under cropland positively affected household level adoption of agroforestry under BTAP; forest cover was negatively related. In-depth interviews show that key barriers to FD in diffusion of agroforestry included provision of false information by farmers to monitoring teams, non-availability of extension staff, lack of communication among project staff and community, as well as a lack of sufficient budget for activities. Primary barriers to community adoption of agroforestry included no participation of VDCs in planning and monitoring of agroforestry programs, lack of plant need assessments on the part of the project staff, poor quality of plants distributed by FD, farmers’ poor know-how of plantations, lack of trust among community and project staff, as well as the waste of plants by farming community. Thus, this study recommends that policy-makers and project designers should consider these factors when planning agroforestry diffusion under 10-BTAP to improve its success.

Climate change is major challenge in modern era and requires key attention to the researcher, globally. Carbon (‘C’) sequestering through agroforestry is one of the ways to mitigate the carbon reduction and provide safeguards to the environment for livelihood. The present study was conducted on Grewia optiva tree which is dominated in agroforestry systems of Tehri Garhwal Himalaya (Uttarakhand) in different villages at three altitudes, i.e., upper altitudes (UA), middle altitude (MA), and lower altitude (LA) ranged from 500 to 1500 m amsl. Soil moisture, water holding capacity (WHC), bulk density (BD), and soil organic carbon (SOC) reported highest in LA compared to MA and UA, which might be because of all eroded material deposited in LA . Further, nitrogen storage in UA is higher due to comparatively low temperature significantly lower the microbial activities for N2O emission than MA and LA. The low nitogen in LA might be due to higher nitrification and/or denitrification rate. The same also supported by low carbon content (energy sources to microbial activity) in LA. The density of Grewia optiva in agroforestry was high in LA; however, total tree carbon was highest in MA (20.8 t/ha) followed by UA (20.4 t/ha) and LA (19.1 t/ha) while annual shoot carbon was highest in LA (2.43 t/ha) followed by MA (1.08 t/ha) and UA (0.77 t/ha). Further, carbon credit likely to be earned from the agroforestry under G. optiva is estimated as 553,702 Euro. Therefore, Grewia optiva is strongly recommending for agroforestry which will further help in socioeconomic development and carbon-reducing strategies in mitigating future climate.

Agroforestry practices coupled with wastewater irrigation systems are sustainable strategies for water management. The performance of these practices could be improved by rhizobioaugmentation. This approach would be particularly useful in developing countries where it can be used as a low-cost tool to control widespread environmental contaminations. The main objectives of the present study are to (1) determine the effects of wastewater on metal/nutrient contents in soils, (2) assess the pattern of metals in Casuarina glauca, and (3) analyze the effects of rhizobioaugmentation of C. glauca growing in industrial wastewater–irrigated agricultural soil using N-fixing Frankia symbionts. Overall, the wastewater treatment significantly increases the levels of total Pb, B, Cr, Mn, Na, Sr, Zn, As, Co, Sb, Sn, and Fe. Only a small portion of total metals/nutrients were phytoavailable. The bioaccumulation in roots of all the metals/nutrients measured was high while the translocation from roots to aerial parts showed insignificant level of movement of the elements tested. Based on bioavailable metals/nutrients, the bioaccumulation factors were 34, 41, 94, 196, 584, 587, 1859, and 9917 for Mg, As, Ni, Mn, Cu, Co, Cr, and Pb, respectively. Hence, C. glauca is classified as a metal excluder. Rhizobioaugmentation with Frankia resulted in an increase or a decrease of metals/nutrients in soil depending on the bacterial strain used and the metal/nutrient element. It also increased significantly the bioaccumulation in roots of some metals and the uptake of key nutrients such as Ca, Na, and K by Casuarina plants. Overall, the results of the present study showed that C. glauca is suitable for phytoremediation of metal-contaminated soils. The use of Frankia represents a potential approach of managing Casuarina glauca wastewater–irrigated soil system.

The dynamics in climatic variability is prominently affecting the agriculture system, particularly the small and marginal land holding farmers in arid and semi-arid regions which are highly vulnerable. The present study in Kolar district assessed the variability scale and dynamics of rainfall over the decades, it revealed the current day’s agrarian crisis, resulting in impacts on farmers and adaptations by farmers to changing situations. The study also reveals that over the decades there has been a considerable variation in rainfall pattern in the study area but there was no significant average rainfall variation till the last decade, after which there was a significant seasonal variation that directly affects the sowing pattern and associated agricultural practices. The exploitation of groundwater for water-intensive commercial crops has increased rapidly from the past decade that resulted in the critically depleted groundwater table. To meet the livelihood demands some farmers were observed to have shifted to non-agricultural occupations. It is a serious threat at this point of time as the agriculture output has to be fed to the larger portion of the society and decreased output from agriculture eventually leads to inflation. So, it is very crucial to adapt all possible measures to retain farmers in agriculture practice. Hence, understanding and scientific assessment of the risks associated with the changing climate and its variables is the need of the hour, particularly in arid and semi-arid regions which are going to be highly vulnerable. Studies like this will help in policy-making and management planning to cope up with the dynamic climatic factors.

Traditional agroforestry systems, one of the time tested and dominant land use from tropical to sub-tropical regions, were recognized for their contributions to food production, biodiversity conservation, and atmospheric carbon sequestration. Their management often varies from region to region. However, these systems frequently mimic economically managed land uses due to increased pressure on the monetary requirement of their managers. The present study aims to evaluate (i) tree density, (ii) tree diversity indices, and (iii) identify the biomass carbon important tree species managed by different communities of the Indian Eastern Himalayan region. We found that the Mizo community harbored the highest number of tree species (35) in the traditional agroforestry system with the highest tree diversity index (3.47). Total biomass carbon of tropical agroforestry systems managed by different communities ranged between 4.72 Mg ha⁻¹ (Meitei) and 29.26 Mg ha⁻¹ (Bengali). Similarly, in the sub-tropical traditional agroforestry system, the highest and the lowest biomass carbon was observed in Mizo- (10.93 Mg ha⁻¹) and Angami- (6.05 Mg ha⁻¹) managed systems. Of the 31 biomass carbon, important species found across the traditional agroforestry systems, Artocarpus heterophyllus, had the highest occurrence (50%), followed by Parkia timoriana (37.5) and Amoora rohituka, Delonix regia, Mangifera indica, and Toona ciliata (25% for each species). Farmers’ preference to cash return of a species, trees density, and basal area were the determinant factors in the carbon stock potential of these systems. The present study suggests that the farmers’ preferred and dominant species in their agroecosystems have a limited scope of enhanced biomass carbon storage. Therefore, improvement of traditional agroforestry systems through selective incorporation of biomass carbon important tree species is recommended to enhance the carbon sink capacity of these systems.

The present study reports the potential of carbon (C) storage in traditional agroforestry systems (i.e., a set of age-old agroforestry systems) under waterlogged environmental conditions from north-eastern India. An experiment was conducted in a farmer’s field and further used CO₂FIX model, allometric equations, and destructive sampling methods to know the potential of C sequestration. In this study area, agroforestry system is dominated by woody perennials like Areca catechu, Cocos nucifera, Mangifera indica, Artocarpus heterophyllus, Melocanna baccifera, and Colocasia esculenta as annual crop component. Need-based management of the drainage system has been built-up by making broad/narrow bunds for maintaining water levels at different stages of plant growth. The total annual carbon storage potential of this traditional agroforestry system was estimated as 103.760±8.630 t ha⁻¹year⁻¹. The highest annual carbon storage potential (97.900±8.090 t ha⁻¹year⁻¹) was recorded in annual crop components (i.e., Colocasia) followed by trees and its underlaid soil (4.250±0.340 t ha⁻¹year⁻¹) and lowest for bamboos (1.610± 0. 200 t ha⁻¹ year⁻¹). However, the estimated carbon stored, annually, was 24.992±1.502 t ha⁻¹ year⁻¹ in which Colocasia share maximum contribution (19.600±1.080 t ha⁻¹ year⁻¹) followed by trees + soil (3.798±0.229 t ha⁻¹ year⁻¹) and the minimum contribution from bamboos (1.594±0.193 t ha⁻¹ year⁻¹). Moreover, total carbon loss from harvesting of this system was 78.768±7.128 t ha⁻¹ year⁻¹. The study, therefore, recommends this agroforestry system for other waterlogged ecosystems at regional and/or global scale under a warm per-humid climate for both livelihood opportunities and environmental sustainability.

In the context of the circular bioeconomy and cleaner production, the incorporation of the by-products of plant biomass production in the bioenergy chain is fundamental. However, lignocellulosic wastes have properties that hinder their use for the production of biofuels. This study aims to evaluate how blends of lignocellulosic wastes improve the physical, chemical, and mechanical quality of pellets destined to the industrial sector, and to identify the challenges associated with the use of agroforestry biomass as raw material for pelletizing. Pellets were produced from blends of soybean wastes, sorghum wastes, pine needles, rice powder, Eucalyptus sawdust, and charcoal fines. Additionally, pure pellets composed of soybean wastes, sugarcane bagasse, and pine wood were evaluated. The effect of biomass type on the energy density, ash content, net heating value, and ultimate analysis was significant. The pellets produced with soybean wastes presented high contents of N (3.5–4.9%) and ashes (16.4–26.7%), besides low mechanical durability (≤ 96%), hindering its commercialization for industrial purposes. Pellets with sugarcane bagasse presented N (1.5%), S (0.03%), ashes (5.6%), mechanical durability (96.6%), and net heating value (15.1 MJ kg⁻¹), suitable for industrial energy use in accordance with ISO 17225-6. The high N and ash contents and the low mechanical durability are the greatest challenges for the energy use of pellets produced from Brazilian agroforestry wastes.