Ashar Tahir, Zhang Yingying, Yang Chuan, Xu Wenxian, Zeeshan Ul Haq Muhammad, Tahir Hassam, Abbas Hafiz Muhammad Mazhar, Wu Zhixiang
College of Ecology and Environment, Hainan University, Haikou, 570228, China.
Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China.
Sci Rep. 2025 Jan 25;15(1):3196. doi: 10.1038/s41598-025-87293-0.
Agroforestry systems are known to enhance soil health and climate resilience, but their impact on greenhouse gas (GHG) emissions in rubber-based agroforestry systems across diverse configurations is not fully understood. Here, six representative rubber-based agroforestry systems (encompassing rubber trees intercropped with arboreal, shrub, and herbaceous species) were selected based on a preliminary investigation, including Hevea brasiliensis intercropping with Alpinia oxyphylla (AOM), Alpinia katsumadai (AKH), Coffea arabica (CAA), Theobroma cacao (TCA), Cinnamomum cassia (CCA), and Pandanus amaryllifolius (PAR), and a rubber monoculture as control (RM). Soil physicochemical properties, enzyme activities, and GHG emission characteristics were determined at 0-20 cm soil depth. The results showed that agroforestry systems significantly enhanced most of soil nutrient levels and enzyme activities. In 0-20 cm soil depth, all rubber plantations acted as net carbon dioxide (CO₂) and nitrous oxide (N₂O) resources, and net methane (CH₄) sinks. Compared with the RM, the CAA and CCA systems significantly increased the cumulative CO and NO emissions, and the global warming potential (GWP) significantly increased in the CAA (36.78%) and CCA (7.18%) systems, whereas it significantly decreased in the AOM (6.61%), AKH (24.96%), TCA (14.24%), and PAR (41.01%) systems. The soil DOC concentration was the primary factor influencing GHG emissions and GWP. This study provides novel insights into GHG emissions from rubber agroforestry systems and serves as a fundamental reference for climate-smart land use management in rubber plantations. Intercropping rubber trees with arboreal and herbaceous species is recommended over shrub species, considering their beneficial effects in reducing soil GHG emissions and GWP for the sustainable development of rubber plantations on Hainan Island.
已知农林业系统可增强土壤健康和气候适应能力，但不同配置的橡胶基农林业系统对温室气体（GHG）排放的影响尚未完全明确。在此，基于初步调查选取了六种具有代表性的橡胶基农林业系统（包括橡胶树与乔木、灌木和草本植物间作），其中包括巴西橡胶树与益智（AOM）、草豆蔻（AKH）、阿拉伯咖啡（CAA）、可可树（TCA）、肉桂（CCA）和香露兜（PAR）间作，以及橡胶单一种植作为对照（RM）。测定了0 - 20厘米土壤深度的土壤理化性质、酶活性和温室气体排放特征。结果表明，农林业系统显著提高了大部分土壤养分水平和酶活性。在0 - 20厘米土壤深度，所有橡胶种植园均为二氧化碳（CO₂）和一氧化二氮（N₂O）的净排放源，以及甲烷（CH₄）的净汇。与RM相比，CAA和CCA系统显著增加了CO和NO的累积排放量，全球变暖潜势（GWP）在CAA（36.78%）和CCA（7.18%）系统中显著增加，而在AOM（6.61%）、AKH（24.96%）、TCA（14.24%）和PAR（41.01%）系统中显著降低。土壤溶解性有机碳（DOC）浓度是影响温室气体排放和GWP的主要因素。本研究为橡胶农林业系统的温室气体排放提供了新的见解，并为海南岛橡胶种植园气候智能型土地利用管理提供了基础参考。考虑到间作乔木和草本植物对减少土壤温室气体排放和GWP的有益作用，有利于橡胶种植园的可持续发展，因此建议橡胶树与乔木和草本植物间作，而非与灌木间作。
