전토양(田土壤)의 형태적(形態的) 특성(特性)과 유기물함량(有機物含量)과의 관계(關係)

Relationship between morphological characteristics of cultivated upland soils and organic matter content

우리나라 전토양(田土壤)의 유기물(有機物) 함량(含量)을 밝히고 토양(土壤)의 유기물(有機物) 함량(含量)과 주요형태적(主要形態的) 특성(特性)과의 관계(關係)를 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 전토양(田土壤)의 평균(平均) 유기물(有機物) 함량(含量)은 1.73%이며 대부분(大部分)이 0.6~2.5% 범위(範圍)에 있다. 2. 전토양(田土壤)의 토양아군별(土壤亞群別) 유기물(有機物) 함량(含量)을 보면 화산회(火山灰) 황갈색(黃褐色) 반숙토(半熟土)에서 13.0%, 부식(腐植) 황갈(黃褐) 반숙토(半熟土)에서 6.3%로서 많은 편(便)이며 퇴적(堆積) 황갈색(黃褐色) 미숙토(未熟土)는 1.0%로서 가장 적다. 그리고 미숙토(未熟土)의 평균(平均) 유기물(有機物) 함량(含量)은 1.1%에 반(反)하여 반숙토(半熟土)는 2.1% 및 1.8%로서 많다. 3. 토성별(土性別) 유기물(有機物) 함량(含量)을 보면 단면(斷面)의 토성(土性)이 사질(砂質)인 토양(土壤)의 평균(平均) 유기물(有機物) 함량(含量)은 1.0%, 사양질(砂壤質) 1.5% 식양질(埴壤質) 1.8%로서 이들 사이에는 점토(粘土)의 증가(增加)에 따라 유기물(有機物) 함량(含量)도 증가(增加)하지만 식양질(埴壤質)과 식질간(埴質間)에는 큰차(差)가 없다. 이와같은 경향(傾向)은 표토(表土)의 토성(土性)에서도 볼수 있었다. 4. 경사(傾斜)와 유기물(有機物) 함량(含量)의 관계(關係)에 있어서는 평탄지(平坦地)(1.3%)에 비(比)하여 경사지(傾斜地)(1.6%)에서 오히려 많은 경향(傾向)이며 특(特)히 15~30% 경사면(傾斜面)의 유기물함량(有機物含量)은 1.8%로 많았다. 5. 전토양(田土壤)의 적성등급(適性等級)에 따른 유기물(有機物) 함량(含量)은 1급지(級地)에서 1.3% 2급지(級地)에서 1.6% 3급지(級地)에서 1.7% 4급지(級地)에서 1.2%로서 급지(級地)와 유기물(有機物) 함량(含量)과는 관계(關係)가 없었다.

This study was performed to find out the organic matter content, and what is more, the relation between its content and major morphological properties of cultivated upland soils in Korea. The results were as follows. 1. The average organic matter content of cultivated upland soils was 1.73 percent, mostly ranging from 0.6 to 2.5 percent. 2. Examining the organic matter content by subgroup of cultivated upland soils. It was found 13 percent in volcanic ash yellowish brown Cambisols and 6.3 percent in Humic yellowish brown Entisols, Fluventic yellowish brown Entisols was found 1.0 percent, lowest one. The average organic matter content of Entisols, Cambisols, and Argillisols was 1.1, 2.1, and 1.8 percent respectively. 3. According to organic matter content by texture of profile, the average content of sandy soils was 1.0 percent; 1.5 percent in coarse loamy soils; and 1.8 percent in fine loamy soils. The organic matter content increased with an increased clay content in coarse texture group, but there was no significant difference between fine loamy and clayey soil group. This tendency was also observed in surface soil texture. 4. In the relation between slope and organic matter content, its content in flat area was 1.3 percent that is rather low compared to 1.6 percent of sloping area. Especially, cultivated upland soils ranging brown 15 to 30 percent in slope were 1.8 percent which is relatively high. 5. The organic matter content have nothing to do with suitability groups. Itss ontent of I, II, III, IV and V class was 1.3, 1.6, 1.7, 1.2 and 2.0 percent respectively.