Page 3 - ผลการปรับปรุงดินด้วยถ่านชีวภาพต่อปริมาณความชื้นและการแทรกซึมน้ำในดินปลูกมันสำปะหลัง Effect of Biochar for Soil Amendment on Moisture Content and Water Infiltration for Planting Cassava

ห้องสมุดกรมพัฒนาที่ดิน

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ABSTRACT

Biochar improves soil physical properties. Due to its high porosity properties, when added
to the soil, it absorbs moisture, water retention, nutrient absorption. The objective of the study
was to study the effect of Padauk wood biochar on soil moisture and soil infiltration under three
soil-textured group of cassava field areas at Nakhon Ratchasima province. There were 3 different
biochar application rates, without biochar (T1); soil amended with biochar every year 1,000 kg/rai
(T2) and with biochar once, 2000 kg/rai (T3). Data were collected for water infiltration rate and soil
moisture content at a depth of 10, 20, 30, 40, 60 and 100 cm from the soil surface. According to
the three times where the growth period of cassava in 1, 3 months and harvesting period. The

results showed that Padauk wood biochar is very porous. Irregularly small, the pore size ranges
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from 0.4-15 m, with specific surface area values from 50.94 to 71.67 m /g. The pore size
distribution in the medium pore range ranges from 20-47 Å. The moisture content and water
infiltration rate of the soil amended with biochar compared with soil without the biochar were
found. Adding biochar at the rate of 1,000 kg/rai per year and at the rate of 2,000 kg/rai as a
result, the coarse-textured soil moisture was increased at a depth of 60-100 cm. It was found that
3 months after the application of biochar, the water infiltration rate was higher than without the

application of biochar. Medium-textured soil had higher soil moisture at 0-20 cm soil depth when
adding biochar at the rate of 2,000 kg/rai, and the rate of soil water infiltration increased during 3
months until the harvesting period as well as the water infiltration rate of fine-textured soil. It was
found that the fine-textured soil moisture was higher at the soil depth of 60-100 cm after
applying biochar at the rate of 1,000 kg/rai for 2 years. Considering cassava yields and their
components of cassava. In all three soil-textured groups amended with biochar did not
significantly increase cassava yield. But found that during the first year, the rate of biochar at
2,000 kg/rai effected to stem weight in coarse-textured soil and fine-textured soil, and fresh top
weight in coarse-textured soil was significantly higher than without biochar added.

Key word: Biochar, Moisture content, Water infiltration, Cassava