Reducing carbon emissions and lowering greenhouse gas emissions are key ecological tasks in addressing global climate change, and agricultural and forest ecosystems play a significant role in carbon sequestration and emission reduction, primarily by increasing organic carbon storage and reducing the decomposition of organic carbon, thereby mitigating global carbon emissions to some extent.

This article summarizes the current soil carbon sequestration and emission reduction technologies applied in agricultural and forest ecosystems. Based on this, considering the characteristics of Tea Garden ecosystems, it explores the application potential of these technologies in Tea cultivation, aiming to provide references for promoting eco-friendly and low-carbon cultivation techniques in tea gardens.

1. Current Research Status of Soil Carbon Sequestration and Emission Reduction Technologies in Agricultural and Forest Ecosystems

The main measures to enhance the soil carbon sink function in agricultural and forest ecosystems include increasing organic carbon storage and reducing the decomposition of organic carbon. Currently, soil carbon sequestration and emission reduction technologies in agricultural and forest ecosystems mainly include the scientific return of agricultural and forest residues to fields, scientific fertilization techniques, and scientific cultivation management.

2. Application Potential of Agricultural and Forest Soil Carbon Sequestration and Emission Reduction Technologies in Tea Cultivation

1) Carbon Sequestration and Emission Reduction Potential in Tea Gardens: Tea garden ecosystems are one of the important agricultural and forest ecosystems in China, with both ecological functions and economic benefits. Currently, over 62 countries worldwide grow tea plants, and China is the country with the longest history of tea cultivation and the largest tea production. There are 20 tea-producing provinces and regions in the country, with the total tea garden area reaching 3.3303 million hectares in 2025. Studies have shown that the soil carbon storage in Chinese Tea gardens amounts to 22.5 billion tons, accounting for 71.2% of the total carbon storage in tea gardens, indicating significant potential for carbon sequestration and emission reduction.

2) Application of Soil Carbon Sequestration and Emission Reduction Technologies in Tea Cultivation:

a) Scientific Return of Pruned Tea Plants to Gardens: Pruning tea plants can release apical dominance and stimulate axillary Bud sprouting, thus increasing tea yield. The pruned material from tea plants is mainly composed of plant organic matter, rich in carbon elements. Returning pruned tea plant material to the garden inputs organic matter into the soil, which helps accumulate the soil carbon pool. However, the pruned material decomposes in the soil into CO₂, releasing small amounts of CH₄ and N₂O. If the pruned tea plant material is processed into biochar through high-temperature pyrolysis and then added to the tea garden soil, the biochar's porous structure and large specific surface area can adsorb and retain the existing organic carbon in the soil, reducing the soil respiration rate and effectively decreasing CO₂ emissions. However, the effectiveness of biochar applications is influenced by factors such as the quality of the biochar, the amount added, and soil properties. Therefore, further research and practice are needed in tea garden management to determine the optimal biochar application strategy, achieving effective utilization of pruned tea plant material and soil carbon emission reduction.

b) Scientific Fertilizer Application in Tea Gardens: Scientific fertilizer application in tea gardens can increase tea garden yields, reduce fertilizer waste, and mitigate the negative environmental impacts of chemical fertilizers in tea gardens. Some tea gardens excessively or improperly apply fertilizers to increase tea yield and economic benefits. Overuse of chemical fertilizers promotes the decomposition of organic matter in the soil, affecting nutrient availability and microbial activity, thereby accelerating the release of more CO₂ and N₂O from tea garden soils. Therefore, controlling fertilizer application rates reasonably can reduce greenhouse gas emissions. Currently, new fertilization methods like breaking down chemical fertilizers into small particles or adding inhibitors can reduce nitrogen loss and N₂O emissions. Studies have found that applying nitrogen fertilizers increases the mineralization of existing organic carbon in the soil by 20% to 98%, but co-applying nitrogen fertilizers with biochar significantly reduces the influence of these unstable factors by 6% to 19%.

c) Scientific Application of Cultivation Practices: Scientific cultivation practices have a significant impact on carbon emissions from tea garden soils. Through reasonable fertilization management, soil cover (straw mulch, lawn cover, etc.), integrated water and fertilizer management, intercropping, and crop rotation, the soil carbon storage capacity can be improved, carbon emissions reduced, and sustainable development of tea gardens promoted. However, the selection of cultivation practices should take into account specific soil types, climatic conditions, and tea plant varieties to achieve optimal carbon emission management effects.

3. Summary and Outlook: Based on the “dual carbon” goals, starting from the soil carbon sequestration and emission reduction technologies in agricultural and forest ecosystems, and combining the unique characteristics of tea garden ecosystems, we explore suitable soil carbon sequestration and emission reduction technologies for tea gardens, such as processing pruned tea plant material into biochar for return to the garden, reasonably selecting and using fertilizers, and adopting scientific cultivation practices. These practices not only promote the growth of tea plants and ensure yields but also effectively reduce greenhouse gas emissions from tea garden soils and increase the storage of organic carbon in the soil, thereby better realizing the carbon sink function of tea gardens.