Data from: Large ecosystem service benefits of assisted natural regeneration

China manages the largest monoculture plantations in the world, with 24% being Chinese fir plantations. Maximizing the ecosystem services of Chinese fir plantations has important implications in global carbon cycle and biodiversity protection. Assisted natural regeneration (ANR) is a practice to convert degraded lands into more productive forests with great ecosystems services. However, the quantitative understanding of ANR ecosystem service benefits is very limited. We conducted a comprehensive field manipulation experiment to evaluate the ANR potentials. We quantified and compared key ecosystem services including surface runoff, sediment yield, dissolved organic carbon export, plant diversity, and aboveground carbon accumulation of ANR of secondary forests dominated by Castanopsis carlesii to that of Chinese fir and C. carlesii plantations. Our results showed that ANR of C. carlesii forest reduced surface runoff and sediment yield up to 50% compared with other young plantations in the first 3 years and substantially increased plant diversity. ANR also reduced the export of dissolved organic carbon by 60–90% in the first 2 years. Aboveground biomass of the young ANR forest was approximately 3–4 times of that of other young plantations, while aboveground biomass of mature ANR forests was approximately 1.4 times of that of mature Chinese fir plantations of the same age. If all Chinese fir plantations in China were replaced by ANR forests, potentially 0.7 Pg more carbon will be stored in aboveground in one rotation (25 years). The results indicate that ANR triggers positive feedbacks among soil and water conservation, biodiversity protection, and biomass accumulation and thereby enhances ecosystem services.

中国拥有全球规模最大的人工纯林（monoculture plantations），其中杉木（Chinese fir）人工林占比达24%。最大化杉木人工林的生态系统服务功能，对全球碳循环与生物多样性保护具有重要意义。辅助自然更新（Assisted Natural Regeneration, ANR）是将退化土地转化为生态服务功能更优的高生产力森林的修复实践。然而目前对ANR的生态系统服务效益的定量认知仍十分有限。本研究开展了全面的野外控制实验，以评估ANR的应用潜力。我们定量对比了以米槠（Castanopsis carlesii）为优势种的次生林经ANR修复后的关键生态系统服务功能，并与杉木人工林、米槠人工林进行对照，对比指标涵盖地表径流（surface runoff）、产沙量（sediment yield）、溶解性有机碳输出（dissolved organic carbon export）、植物多样性（plant diversity）以及地上碳积累（aboveground carbon accumulation）。研究结果显示，实验前3年，米槠林ANR修复样地的地表径流与产沙量较其他幼龄人工林降低了最高达50%，同时显著提升了植物多样性。实验前2年，ANR修复样地的溶解性有机碳输出量降低了60%至90%。幼龄ANR修复林的地上生物量约为其他幼龄人工林的3至4倍，而同林龄的成熟ANR修复林地上生物量则约为同龄成熟杉木人工林的1.4倍。若将中国境内所有杉木人工林替换为ANR修复林，在一个轮伐期（25年）内，地上碳库可额外固存约0.7 Pg碳。研究结果表明，ANR可在水土保持、生物多样性保护与生物量积累之间形成正向反馈，从而提升生态系统服务功能。