Chinese fir root response to spatial and temporal heterogeneity of phosphorus availability in the soil

Deficiency in availability of phosphorus (P) in forest soils of southern China, where Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) stands have been established, greatly affects Chinese fir productivity. Deploying clones with high P-use efficiency could be a more attractive option than P fertilization to enhance the commercial productivity of Chinese fir. Thus, an understanding of the adaptive responses of roots to spatiotemporal variability of P, which is often ignored in previous studies, is essential. In this study, we report the root responses of a Chinese fir clone with high P-use efficiency to the spatially heterogeneous P availability in soil during various periods of time when P availability was controlled. The results showed significantly (p < 0.05) more root proliferation in the form of root length, root surface area, root volume, and root dry matter accumulation in P-replete than in P-poor patches when the patch persisted for a short period of time (50 days). As the patches persisted long...