Rainfall interception by a tree's crown is one of the most important hydrological processes in an ecosystem, yet the mechanisms of interception are not well understood. A process-based experiment was conducted under five simulated rainfall intensities (from 10 to 150mmh-1) to directly quantify tree crown interception and examine the effect of rainfall traits and crown structure characteristics on interception for broadleaf (Platycladus orientalis, Pinus tabulaeformis) and needle tree species (Quercus variabilis, Acer truncatum). Results indicated that (1) the interception process was composed of three phases, a rapid increase phase which accounted for approximately 90% of the maximum interception storage (Cmax), a relatively-stable phase, and a post-rainfall drainage phase in which 40% (±16%) of Cmax drained off to reach the minimum interception storage (Cmin); (2) Cmax and Cmin were only correlated with rainfall intensity for P. tabulaeformis; (3) Cmax and Cmin were correlated with both leaf traits (i.e., leaf area, leaf biomass, leaf morphology) and branch traits (i.e., branch density, branch count, branch length, woody surface area, and woody biomass), and the best predictors of Cmax and Cmin were biomass-related parameters; and (4) The needle species P. orientalis had the greatest Cmax, while the largest Cmin was observed in the broadleaf species A. truncatum. Our findings demonstrate the complexity of the interception process and tree characteristics may be more important in controlling interception than rainfall characteristics.
Bibliographical noteFunding Information:
We thank the Jiu Feng National Forest Park Administration, postgraduates Jun Xu, Chen Meng, and Pengwei Bao for their help and support in the experiment. We also thank the two anonymous reviewers for their thoughtful recommendations which have greatly improved the manuscript. This study was supported by the Chinese Scholarship Council Fund ; Fundamental Research Funds for the Central Universities (no. TD2011-03 , no. BLYJ201406 ); National Natural Science Foundation of China ( 41171028 ); Central Nonprofit Research Institutions Basic Scientific Research Special Fund ( HKY-JBYW-2016-04 ); Key Laboratory of the Loess Plateau Soil Erosion and Water Loss Process and Control of Ministry of Water Resources Fund ( 2015004 ). None of the funders had any involvement in study design, data collection and analysis, preparation of the manuscript, nor the decision to submit and publish.
- Branch density
- Leaf area
- Post-rainfall drainage
- Rainfall intensity
- Rainfall interception storage