Chin J Plant Ecol ›› 2019, Vol. 43 ›› Issue (12): 1091-1103.DOI: 10.17521/cjpe.2019.0194

• Research Articles • Previous Articles    

Forest soil phosphorus stocks and distribution patterns in Qinghai, China

TANG Li-Tao,LIU Dan,LUO Xue-Ping,HU Lei,WANG Chang-Ting()   

  1. Institute of Qinghai-Tibetan Plateau, Southwest Minzu University, Chengdu 610041, China
  • Received:2019-08-05 Accepted:2019-11-11 Online:2019-12-20 Published:2020-01-03
  • Contact: WANG Chang-Ting
  • About author:TANG Li-Tao ORCID:0000-0002-4192-6518
  • Supported by:
    Supported by the National Natural Science Foundation(31870407);Supported by the National Natural Science Foundation(31370542);Special Fund Project for Basic Scientific Research Business Expenses of Central Universities(2020NZD03);Sichuan Science and Technology Plan to focus on Research and Development Project(2018SZ033)

Abstract:

Aims Our objectives were to investigate the soil phosphorus (P) stocks and distribution patterns in forests of Qinghai Province, and to determine the relationships between soil phosphorus stocks and environmental factors.
Methods Phosphorus stocks in forest soils of Qinghai Province were estimated from measurement data of 240 standard sampling plots in combination with the forest type information in the Qinghai Forest Resources Inventory data. The distribution patterns were examined by spatial analysis.
Important findings Forest soil P stocks in Qinghai Province is estimated at 1.74 Tg. The average soil P density to 1 m depth is about 4.65 Mg·hm -2, displaying of pattern of zonal distribution. Soil P density significantly decreases first and then increases with altitude, and is largest in Cinnamon forest soils and less in brown forest soils and dark cinnamon forest soils. Soil P content decreases significantly with altitude. The P content was highest in brown forest soils and lowest in dark cinnamon soils. Total P in the soil profile exhibited characteristics of surface accumulation. The structure equation model (SEM) shows that soil type, altitude, temperature, and soil moisture content have direct impacts on soil P content, with temperature and altitude being among the key factors. Soil P content, altitude, soil moisture content, soil depth, and soil bulk density all have significant effects on soil P density, with soil bulk density being the most prominent factor.

Key words: phosphorus stocks, forest soil, spatial distribution pattern, environmental factor, Qinghai