Foliar N:P Stoichiometry in Aralia elata Distributed on Different Slope Degrees

Abstract

Plant nitrogen (N) to phosphorus (P) stoichiometry is of essentially ecological meaning to non-wood forest production (NWFP) plant community in the temperate forest ecosystem. In this study, natural Aralia elata (Miq.) Seem. communities in montane areas of southern Heilongjiang Province, Northeast China were investigated for plant density, vegetative growth, and soil and leaf parameters on slopes in 5°, 9°, and 14° degrees. We found that individual height was greater in sites on 5°- (1.6 m) and 9°-degree slopes (1.9 m) than on the 14°-degree slope (0.8 m), but soil available P content was highest on the steepest slope (5.5, 4.0, and 16 mg kg-1, respectively). The foliar N:P ratio ranged 6–13. Nitrogen availability tended to promote community density and individual growth; while P availability tended to depress density but promote foliar biomass accumulation. By the diagnosis of plant nutritional monogram, the better growth and high foliar N:P ratio of about 13:1 in A. elata individuals on 9°-degree slope were generated by both deficiency-driving N uptake and excessive P depletion. We recommend the 9°-degree slope to develop A. elata community which can be fed by higher N availability if higher density was achieved.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********