Effect Of Soil Compaction In Central And Southern Iraq On Growth And Productivity Of Wheat And Rice Crops

Abstract

A field study was carried out to reveal the effect of compaction of irrigated soils resulting from the movement of heavy machinery adopted in soil and crop management processes in central and southern Iraq on some physical, water and engineering properties of soil. The effect of compaction of heavy and light soils in the fields of cereal crops "wheat and rice" was studied. The study was conducted on eight sites in four stations of different textures, two sites in each station. The four sites are Al-Fajr district, Dhi Qar governorate (mixed texture soil), sand dunes station located on the FAO project between Dhi Qar and Al-Qadisiyah (mixed sandy soil), rice research station in Al-Mashkhab area/Najaf governorate (clay mixed soil), and Al-Qadisiyah-Hor Salib region (Alluvial clay soil). The study focused on comparing sites with compacted soils with sites with non-compacted soils in terms of some of the growth and yield measures (plant length, horizontal root length, deep root length, and dry weight of total yield) of wheat and rice yields affected by soil compaction. The results showed the clear effect of soil compaction on the vegetative growth of wheat and rice crops. In general, a significant decrease in growth indicators and yield was observed in the frequently cultivated compacted soil sites (C1) compared to the neighboring newly planted (un-compacted) sites (C0). This effect was negatively reflected on plant height, root system and yield, and led to a decrease in total yield in Qadisiyah and Mashkhab stations, which are characterized by clay soil, and Al-Fajr station with mixed soil. In general, the compaction operations affected the physical properties of the soil and led to a clear imbalance in the growth systems and yield indicators. This is in addition to the risk of soil detoriration over time and an increase in compaction due to pressure and repeated cultivation.