INTERNATIONAL JOURNAL OF AGRICULTURAL TECHNOLOGY

Volume 15, No. 05, Month SEPTEMBER, Year 2019, Pages 779 - 790

Spatial distribution of soil quality using geoinformatics in agricultural areas in nang lae sub-district, mueang district, chiang rai province

Suk-ueng, K., Chantima, K. and Prasertsin, T.

Abstract Download PDF

Agricultural areas in Nanglae Sub-district is the main agricultural area of Mueang District, Chiang Rai Province that required soil monitoring on current utilised agricultural areas for sustainable agricultural management. Geoinformatics integrated with soil quality can be used for categorizing soil quality on different agricultural classes. Firstly, Thaichote satellite imageries were used to digitally classify the agricultural area into three agricultural classes, namely paddy fields, field crops (pineapple) and orchards (lychee / longan / lemon / pomelo). Secondly, 9 collected soil samples from the agricultural areas, and physic-chemical properties and arsenic content were reported. The results of image processing, total accuracy of agricultural mapping based on minimum distance classifier that was 22.22% with K statistic of -0.15. This map was used to support soil quality analysis. The soil sample of different agricultural areas was slightly acid (pH 5.93-6.93). Organic matter content of these soils was low (0.13-2.07%). These soils had low total nitrogen (1,200-2,800 mg/kg). The available phosphorus and potassium were very low to low ranged from 1.86-5.94 mg/kg and 0-78.00 mg/kg, respectively. These soils were low soil fertility status, which indicated that physicochemical properties were not suitable for crop cultivation. Interestingly, soil samples from paddy fields and orchard fields, near the reserved forest area (Doi Nang Lae, Doi Yao and Doi Prabhat reserved forest), were contaminated with high arsenic content (4.50-6.32 mg/kg), which was higher than the standard of National Environment Board of Thailand.

Keywords

Geoinformatics, Soil quality, Chiang Rai Province

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