|
|
|
Interpretive Summaries:
Soil Nutrient Mapping in La Pampa Province, 2007
The expansion of grain crop production towards the western areas of the Pampas region of Argentina has, to date, had a negative impact on soil P and organic matter (OM) levels because of erosion and nutrient removal via harvested grain. Soil pH levels have also decreased recently. This project updated the Bray P-1 map assembled in 1996, and developed two maps on soil OM and pH for the province of La Pampa. Information on Bray P-1, OM, and pH from 874 soil samples (0 to 20 cm) from the eastern region of La Pampa province was incorporated into a database and mapped using ArcView(R) software.
Soil Bray P-1 levels were highly variable according to the different areas and management history. Approximately 70% of the samples were below 20 mg/kg, indicating an increasing area of P responsive soils. Most of the areas presented pH values between 6.2 and 7.5, with some areas of longer cropping history between 5.2 and 6.2. Soil pH values below 6.2 could indicate potential problems for alfalfa and/or soybean production. Soil texture and cropping history and cropping intensity varies greatly in this region and this affects soil OM content. Values of soil OM fell between 1.5 to 2% in the southern and western areas of the region and 1 to 1.5% in the northeastern area. Argentina-26
|
|
