Paddy Soil Properties in Nangarhar Province, East Afghanistan

その他

Paddy soil properties in 20 villages in Nangarhar province, East Afghanistan were investigated. The soils, which were mostly classified as sandy loam or loam, were alkaline and contained carbonate ranging from 4.9 to 16.9 g C kg–1. The average total N and organic C, (0.36 N and 6.2 C g kg–1) was low compared to the average values in tropical Asian paddy soils. Calcium was the predominant exchangeable cation followed by Mg, K and Na in that order. The available P (Olsen-P) content was 20.7 mg P2O5 kg–1 on average and did not vary significantly throughout the study area, while the available Si content, (261 mg SiO2 kg–1) was comparable with the level in tropical Asia. The available micronutrients (DTPA-TEA extraction) Fe, Mn, Cu and Zn, were 35.9, 9.6, 4.75 and 0.33 mg kg–1 on average. The paddy soil properties were generally low in fertility compared to those in tropical Asia, while the available P and Zn contents were deficient for rice growth. Paddy fields in Nagarhar province could be divided into groups according to the location. The paddy soil properties varied in Kabul and Kunar watersheds and were influenced by spot distribution of different types of parent materials such as limestone, dolomite and lava.