Multi-scale Ecological Adaptation of a Young Mixed Broadleaved and Coniferous Korean Pine Forest Community to Drought

摘要

The multi-scale mechanisms of how communities or ecosystems adapt to drought are important for natural resources management and developing mitigation strategies under global climatic change. We studied the adaptive response from different scales of a young mixed broadleaved and coniferous Korean pine forest community (YMBCKPFC) under temporary water limitation or drought in Northeast China. YMBCKPFC acclimated to water limitation, or drought pulse, from community scale to plant species and plant leaves. Leaf water content and water potential were lower for most plant species at water limitation. For all species the leaf evapotranspiration increased and stomatal conductance decreased. Photosynthetic rates of many species decreased first and then increased, but others continue to increase their photosynthetic rates. Most species adapted to water limitation by decreasing their growth rate. Fruits of Rosa suavis became mature earlier under drought conditions. Soil respiration increased as the soil water content decreased. The total water consumption of YMBCKPFC decreased slightly under water limitation. The spatially heterogeneous distribution of soil water was advantageous for YMBCKPFC to adapt to water limitation. The contents of soil nutrients changed under drought condition. Soil P decreased and soil K increased, but the change of soil total C, N and S seemed complicated. Functional convergence and divergence of basic physiological processes existed while YMBCKPFC adapted to drought at multi-scales. The functional divergence or response diversity may be helpful to the survival and succession of this community.