Evaluation of integrated farming system on acidic soil and saltwater intrusion in the coastal area of Kien Giang province

Abstract

Research on the characteristics of acidic and saline soils in coastal areas to evaluate the adaptation of crops (rice, sedge) and aquatic species (snails, tilapia), and compare the financial performance of integrated farming systems and rice monoculture. The experiment was conducted on the field land affected by drought and saltwater intrusion in two ecological regions of Kien Giang province. The results showed that acidity and salinity factors affect the rice yield of the winter-spring crop. The sedge plant (Cyperus malaccensis) grew well under the pH and salinity conditions of the experiment, but sedge productivity in the dry season was lower than in the rainy season. Snails (Pila gracilis) adapted well to experimental conditions, so the survival rate reached 53-79%. The weight gain of tilapia (Oreochromis niloticus) was from 0.45 to 0.96 g/day, but fish yield was still low (226-541 kg/ha), due to a low survival rate (30-36%). Analysis of overall financial efficiency showed that the integrated farming system was more effective than 2 rice crops/year. The profit of the integrated farming system was higher than that of rice (262 to 268 million VND compared to 22-40 million VND/ha/year). Therefore, diversified land use in coastal areas to grow sedge plants, combined with raising snails and tilapia, increased household income in the research sites.