In the context of agricultural green transformation, the balance between the environmental footprint and economic return is a key indicator for measuring the synergy of high yields, high efficiency, and environmental friendliness in agricultural systems. However, the pathways and mechanisms for achieving this synergy in orchard systems remain unclear. Based on a three-year field experiment in Pinghe County, Fujian Province, a comprehensive evaluation framework integrating life cycle assessment (LCA) was constructed. This framework was used to systematically analyze the differences in the net ecosystem economic benefit (EEB) and environmental impact of four fertilization regimes: the conventional farming regime with no mulching (A; 1084 kg N ha⁻¹, 914 kg P₂O₅ ha⁻¹, and 906 kg K₂O ha⁻¹), the conventional farming regime with mulching (B), the optimized fertilization regime with water–fertilizer integration (C; 250 kg N ha⁻¹, 200 kg K₂O ha⁻¹, 100 kg MgO ha⁻¹, and 400 kg CaO ha⁻¹), and the optimized fertilization regime with controlled-release fertilizers (D). The results showed that regime D performed best in terms of yield, nutrient-use efficiency, and EEB, which increased by 220.5% and 297.5% compared with regime A, and reduced the input cost by CNY 63,100~69,000 hm⁻². Moreover, compared with regime A, regimes B, C, and D significantly reduced the carbon, nitrogen, and phosphorus footprints, respectively, with the carbon footprint reduced by 6.7~21.7%, 72.4~74.8%, and 71.6~76.5%; the nitrogen footprint reduced by 2.6~19.0%, 80.7~82.2%, and 80.1~83.4%; and the phosphorus footprint reduced by 15.3%, 100%, and 100%. Furthermore, the comprehensive evaluation index (CEI) is D > C > B > A. In total, the three optimized regimes balanced high yield with environmental sustainability, with the D regime showing the best performance, offering scientific support for transitioning to low-carbon, high-value orchards in smallholder systems.

Excessive nitrogen fertilizer application in tea plantations is a common problem that leads to soil acidification and reductions in both yield and economic returns. To evaluate the impacts of varying nitrogen input levels (0–600 kg N ha⁻¹ yr⁻¹) on yield, as well as environmental and economic outcomes, a two-year field experiment was conducted. Results demonstrated that when nitrogen application exceeded 150 kg N ha⁻¹ yr⁻¹, key efficiency indicators—agronomic efficiency (NAE), recovery efficiency (NRE), and partial factor productivity (NPFP) declined markedly. Among all treatments, the 150 kg N ha⁻¹ yr⁻¹ rate achieved the highest NRE at 28.01%. Moreover, environmental burdens including global warming potential, acidification, and eutrophication intensified with increasing nitrogen input. Benefit analysis revealed that yield-based economic returns peaked between 150 and 165 kg N ha⁻¹ yr⁻¹, whereas the highest ecosystem economic benefit, accounting for both profit and environmental cost, occurred at 120 kg N ha⁻¹ yr⁻¹. Thus, 120 kg N ha⁻¹ yr⁻¹ is identified as the optimal application rate for maximizing integrated economic and environmental returns while maintaining yield. These findings provide valuable guidance for promoting sustainable nitrogen management in tea cultivation worldwide.

Soil acidification and base cation depletion constrain sustainable pomelo production in subtropical orchards. We hypothesized that the co-application of organic fertilizer and dolomite powder would alleviate soil acidification, improve Ca and Mg supply, and enhance pomelo yield and fruit quality more effectively than either amendment alone. A two-year field experiment was conducted in a pomelo orchard in southern Fujian Province, China. Four treatments were established: optimized fertilization alone (CK, 200 N-0 P₂O₅-200 K₂O kg ha⁻¹), optimized fertilization plus organic fertilizer (OF, 200 N-0 P₂O₅-200 K₂O kg ha⁻¹ + 7500 kg ha⁻¹ organic fertilizer), optimized fertilization plus dolomite powder (DP, 200 N-0 P₂O₅-200 K₂O kg ha⁻¹ + 2145 kg ha⁻¹ dolomite powder), and optimized fertilization plus organic fertilizer and dolomite powder (OF + DP, 200 N-0 P₂O₅-200 K₂O kg ha⁻¹ + 7500 kg ha⁻¹ organic fertilizer + 2145 kg ha⁻¹ dolomite powder). Pomelo yield, economic benefits, fruit quality, fruit mineral nutrients, and soil physicochemical properties were determined using standard procedures. Soil analysis showed that OF + DP most consistently increased soil pH and exchangeable Ca and Mg, while organic fertilizer improved soil organic matter. Compared with CK, OF + DP increased yield by 34.27% and 30.13% in 2023 and 2024, respectively, mainly by increasing fruit number per tree. OF + DP also produced the highest net profit, improved total soluble solids and TSS/TA, and increased fruit K, Ca, and Mg concentrations. These results indicate that combining organic fertilizer with dolomite powder is an effective amendment strategy for improving acidified pomelo orchard soils and productivity.