خلاصة:
Although fertility capability classification (FCC) has high performance in land evaluation and soil maps interpretation, so far it has been less attended in land evaluation studies. Therefore, qualitative (FCC method) and quantitative (Riquer index) land fertility capability evaluation for Wheat and Rice cultivation and comparison of Soil Taxonomy and WRB classification with FCC were chosen as this study objective. After field and laboratory studies, the soil map was prepared with the scale of 1: 50,000. Then, FCC and Riquer methods were used to determine the land fertility capability for Wheat and Rice cultivation for each of the soil map unites. Investigations showed that the FCC and Riquer methods have presented similar results and well interpreted and classified soils. The results of Riquer method indicated that the fertility capability of these lands is good except in gravelly and shallow parts, thus Wheat and Rice can be cultivated in these soils. A comparison of the current soil classification systems and the FCC results showed that the problems and inherent characteristics of studied soils were pointed well by the FCC system, whereas they have been expressed differently in Soil Taxonomy and WRB classifications. Gleyic condition, dryness and subsoil gravel are the most limitative factors to Wheat and Rice cultivation in this area.
ملخص الجهاز:
Therefore, qualitative (FCC method) and quantitative (Riquer index) land fertility capability evaluation for Wheat and Rice cultivation and comparison of Soil Taxonomy and WRB classification with FCC were chosen as this study objective.
Then, FCC and Riquer methods were used to determine the land fertility capability for Wheat and Rice cultivation for each of the soil map unites.
The results of Riquer method indicated that the fertility capability of these lands is good except in gravelly and shallow parts, thus Wheat and Rice can be cultivated in these soils.
Considering 9 factors including humidity condition, drainage, effective depth, soil texture and structure, base saturation percentage, accumulation of soluble salts, organic carbon content, cation exchange capacity, clay type and element storage, the fertility index of each soil is calculated (Riquer, 1970).
Determining the fertility classes of these soils and interpreting the soil map of the area, as well as comparing the fertility classification (FCC methods and Riquer) and soil taxonomy (Soil Taxonomy and WRB) are the other objectives of this study.
In this regard, a productivity index (PI) was calculated based on land and soil characteristics which affect plant yield, with: PI= H * D * P * T * N or S * O * A * M (1) Where, H: soil moisture, D: drainage, P: effective depth, T: soil texture and structure, N: base saturation percentage and S: soluble salts, O: organic carbon content, A: CEC of clay mineral, and M: mineral reserve.
(
, 
, 
)
