🌿 Successive Planting of Eucalyptus grandis Plantations: A Hidden Threat to Soil Carbon Reservoirs
Eucalyptus grandis , a fast-growing and commercially valuable tree species, has been widely planted for timber and pulp production 🌳. While it supports economic growth, successive or repeated planting cycles pose ecological concerns, particularly regarding soil organic carbon (SOC) — the cornerstone of soil fertility and ecosystem health 🌎. ⚗️ 2. Understanding Soil Organic Carbon (SOC) SOC represents the carbon stored in soil organic matter — derived from decayed plants and microorganisms. It governs nutrient cycling, soil structure, and water retention 💧. However, with each successive Eucalyptus grandis rotation, SOC and its labile (easily decomposable) fractions show a steady decline, reducing soil productivity and resilience. 🌾 3. Mechanisms Behind the Carbon Decline 🔄 a) Litter Quality and Decomposition Eucalyptus leaves are rich in lignin and essential oils, making their litter slow to decompose ⏳. This hinders carbon input to the soil, causing a negative carbon ba...