Identifying the critical sources areas of non-point particulate phosphorus based on an index approach in R: A case study in red soil hilly micro-watershed [基于R语言的非点源颗粒态磷指数构建及应用-以丘陵红壤区小流域为例]

作者：Su J.-J.; Zhao H.-T.^*; Jiao R.-Y.; Fang Z.-D.; Yang X.-J.; Li X.-Y.

来源：China Environmental Science, 2021, 41(4): 1868-1877.

• Critical source areas
• Non-point source particulate phosphorus
• R
• Red soil hilly area
• Subregion management

This study developed a watershed-scale non-point source (NPS) particulate phosphorus (PP) index based on R statistical language and applied it in a red soil hilly subbasin. The results indicated that watershed soil erosion rates ranged from 0.7 to 15244.2 t/(km2?a), and 59% of the watershed area exceeded the regional soil erosion threshold. The average watershed NPS PP load was 0.86 kg/hm2 and approximately 14% of the watershed area exceeded the NPS P loss threshold. Despite the fact that dominate soil erosions in the watershed were slight to mild, the small areas (7.2%) categorized as moderate to severe erosions contributed considerably larger shares to the total watershed loads of erosion and NPS PP loss (31%~43%). The critical sources areas (CSAs) for soil erosion and NPS PP loss were identified as 6.4 km2 in area, mainly consisting of wood land, crop land and orchard land, which were adjacent to streams (≤800m) and with low to gentle slopes (< 25°). The soil P enrichment due to excessive fertilization, as well as the high erosion potential facilitated the formation of these CSAs. The CSAs were further divided into zones according to land uses, hydrological distances and slopes, on which different management practices and strategies were recommended to target the erosion and NPS PP loss.

• 单位
  中国科学院大学