Document Type : Research Paper

Authors

• n d
• a z
• m sh
• l r
• m k
• h sh
• m sh
• e k
• a sh
• i b
• sh a
• e m
• a kh
• h sh
• f d
• a r
• a a

Abstract

 
Rational use of fertilizers in soil depends on the awareness of the condition of
fertility and nutrient in soil. One approach is based on a comprehensive
understanding and correct use of precision agriculture of agricultural soils. Thus
the map of spatial variability of soil properties is a key step in the application of
precision agriculture which based on the map, application of agricultural inputs
could be managed in a systematic way. To this end, comprehensive study of
paddy soils fertility in Guilan province through GIS mapping were counducted.
Soil characters including Total N, P, K, pH, EC, OC and clay were measured in
8567 soil samples collected from arable land of Guilan province. These characters
were analyzed through descriptive statistics, geostatistics and GIS. Mapping
showed that most soils of the province in terms of pH and EC were favorable for
the growth of rice plants, while total nitrogen, potassium and phosphorus need to
be managed. Many paddy fields in the Central Plains area of Guilan and in the
alluvial soils of Sepeedrud basin showed nitrogen deficiency which soil response
to nitrogen fertilizer is high. In nearly 40% of the land surface, P concentration is
less than critical level because of the continued cultivation of plants without use
of phosphate fertilizers by farmers or the low ability of soil to preserve native soil
phosphorus. Agricultural land of Guilan province was divided into Eastern and
Western parts based on potassium content. In the most part of western area,
available potassium is low, while in the eastern part, available potassium was
higher than western part because of Sepeedrud sediment. In nearly 68% of the
study area available potassium of soil was less than critical level(160 mg per kg)
for growing cultivated Rice. The results in general showed that the nutrient status
of paddy fields is not distributed uniformly from geographical point of view
.Therefore, to prevent soil fertility decline and increase of production cost
fertilizer distribution in the region and consumption of fertilizer in the field should
be based on achieved results

Keywords

• Ffertility status
• G
• Geostatistics
• M
• Mapping
• Ppaddy fields