Integrated ecological rice farming regulation of soil phosphorus
fraction conversion and effectiveness through organic carbon and
phosphatase activity
Abstract
Objective of investigation: Integrated ecological farming
combines rice growth and aquaculture, and is an effective way to improve
soil productivity by increasing soil nutrient supply and reducing
agricultural non-point source pollution. We investigated the impacts of
cultivation patterns, including integrated ecological farming (IEF),
rice and vegetable rotation pattern (RVP), and conventional rice
cropping pattern (CRP), on the characteristics of soil phosphorus in the
Pearl River Delta (PRD). Experimental material: The study area
was located in Zengcheng District, Guangzhou City, China. Method
of investigation: Tiessen’s classification was used to analyze soil
phosphorus fraction contents and its availability. Data
collection: Following rice harvesting, topsoil (0–10 cm) and subsoil
(10–20 cm) were collected from each field via an S-shaped 5-point
sampling method, and the collected samples were mixed into a single
sample. Result and conclusions: SOC and phosphorus fractions
were significantly influenced by cultivation patterns; IEF significantly
increased SOC and phosphorus in the soil. Soil phosphorus was dominated
by moderately labile P (40.67–49.41%). IEF also significantly
increased soil microbial biomass carbon, phosphorus, and acid
phosphatase (ACP) by 67.68, 46.68, and 15.87% compared to RVP, and by
134.14, 65.99, and 30.20% compared to CRP, respectively. SOC and ACP
were the primary factors influencing the conversion and effectiveness of
soil phosphorus. The integrated ecological cropping pattern can
alleviate low phosphorus activity in PRD paddy soils while promoting a
sustainable soil nutrient cycle within the ecosystem and guiding the
sustainable development of rational soil fertilization in the region.