Synergistic Enhancement Mechanisms and Eco-Economic Value of a “Fruit-Medicinal Herb-Edible Fungus-Bee” Integrated Model in the Litchi Industry

To address the problems of cultivar aging, yield fluctuation, and inefficient resource utilization in the litchi industry, a four-dimensional planting and breeding model integrating fruit, medicinal herb, edible fungus, and bee was proposed. The synergistic enhancement mechanism and eco-economic value of this model were investigated through technological integration and methodological innovation, so as to provide a practical approach for rural revitalization and the achievement of the dual-carbon goals.

By coupling data envelopment analysis (DEA) with life cycle assessment (LCA), a two-dimensional evaluation framework for resource-use efficiency and carbon emissions was constructed, and further combined with cost-benefit analysis (CBA) and multi-criteria decision analysis (MCDA) for comprehensive assessment. The integrated technologies included grafting of the litchi cultivar Xianjinfeng (cambial division rate of 3.2μm·h^-1), epiphytic cultivation of Dendrobium officinale (survival rate of 96.26%), cultivation of edible fungi using pruned branches as substrate (ligninolytic enzyme activity of 4.8 U·mg^-1), and pollination by Apis cerana (fruit-setting rate of 78%). The DEA-BCC model under variable returns to scale was adopted, with land, labor, capital, and material inputs such as fertilizers and pesticides as input indicators, and economic return and carbon-emission reduction as output indicators. LCA was conducted in accordance with ISO 14044 to quantify life-cycle carbon emissions. Data were collected from 50 planting units from 2019 to 2024, including 30 units under the four-dimensional model and 20 units under the conventional model. Monte Carlo simulation with 10000 iterations was used to control uncertainty within 15%.

Compared with the conventional model, the four-dimensional model showed significant advantages. The DEA comprehensive efficiency reached 0.92, much higher than 0.16 under the conventional model. Light interception efficiency increased to 86%, and the utilization rate of pruned branches reached 100%. Carbon emissions were reduced by 32% (1.2 vs. 1.8 t CO₂-eq/mu, 1 mu=666.7 m²), among which branch recycling contributed 0.66 t CO₂-eq/mu (60% of total emission reduction), and bee pollination contributed 0.18 t CO₂-eq/mu (15%). Net profit reached 101500 yuan per mu, with a static payback period of 0.76 years and an internal rate of return of 129%. MCDA results showed that the comprehensive score of the four-dimensional model was 0.82, significantly higher than 0.21 for the conventional model, and the former performed best in resource-use efficiency (0.92), carbon reduction (0.6 t CO₂-eq/mu), and employment promotion (120 persons per 100 mu).

The fruit-medicinal herb-edible fungus-bee” four-dimensional planting and breeding model formed a diversified income structure through the synergistic effects of light-energy utilization, resource recycling, and pollination enhancement, thereby effectively mitigating the risk of alternate bearing in litchi production. Its major innovations included the expanded adaptation of Dendrobium officinale to high-light conditions (Fv/Fm = 0.82), efficient branch decomposition by highly active fungal strains (decomposition cycle of 45 d), and a performance evaluation framework based on DEA-LCA coupling. This study provided a technical paradigm for the implementation of the “High-Quality Development Project for Counties, Towns and Villages” in Guangdong Province and offers theoretical and practical support for the green transformation of agriculture.