Author(s)

Jorge H. Ramírez-Silva¹, Matilde Cortazar-Rios^2*, Genovevo Ramírez-Jaramillo¹, Carlos M. Oropeza-Salín³, Dinosca N. Rondón-Rivera⁴

¹Centro de Investigación Regional Sureste del Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), Mérida, México.
¹Centro de Investigación Regional Sureste del Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), Méri-da, México.
²Campo Experimental Chetumal del Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), Chetumal, México.
³Centro de Investigación Científica de Yucatán (CICY), Mérida, México.
⁴Investigadora Independiente, Mérida, México.

The productivity of coconut in Guerrero, Mexico has decreased substantially. The experts recommended a diagnosis of the soil fertility before launching a sound reforestation program. The introduction of Green Dwarf Coconut (GDC) due to its high productivity was suggested; however, nitrogen (N) was of higher interest since GDC is a highly demanding material. In this work, the contents, in parts per million (ppm), of nitrogen (N) as nitrate (N-NO₃) as well as its chemical variability (Coefficient of Variation) and spatial distribution (Kriging method) was determined at 0 - 30 and 30 - 60 cm deep in the soil. Two GDC commercial plantations were selected and the study was complemented with foliar N (%) analysis. Two farms: Las Tunas (LT) of 9 hectares and Aguas Blancas (AB) of 5 hectares were sampled taking one point per hectare at both depths, one meter from the trunk. In LT, the overall average of N-NO₃, at 0 - 30 cm, was rated as MEDIUM and at 30 - 60 cm as LOW. On the other hand, in AB the general average of N-NO₃ was graded as LOW at both depths. The two farms showed important chemical heterogeneity as indicated by the HIGH CV’s (%). Regardless of the specific values of N, in LT the spatial distribution of N seems to be the same between both depths with an approximate area of 20% classified as LOW (14 - 18 ppm) and 80% as MEDIUM 20 - 28 (ppm). On the other hand, in AB the spatial distribution was contrasting between depths. At 0 - 30 cm deep, an approximate area of 15% was rated as LOW and 75% as MEDIUM whilst at 30 - 60 cm deep, 70% was LOW, 28% MEDIUM and just 2% HIGH. Although both farms showed LOW foliar N contents, as compared to the critical range of 1.8% - 2.0%, AB was the one reporting the lower N value of 1.16% vs. LT with 1.44%, both in deficiency levels.

Kriging, Foliar N, Deficiency, Heterogeneity, Critical Level

Ramírez-Silva, J.H., Cortazar-Rios, M., Ramírez-Jaramillo, G., Oropeza-Salín, C.M. and Rondón-Rivera, D.N. (2022) Heterogeneity and Spatial Distribution of Inorganic Nitrogen as Nitrate (N-NO₃) in Two Soils Dedicated to Green Dwarf Coconut in Guerrero, Mexico. Open Access Library Journal, 9, 1-11. doi: 10.4236/oalib.1109367.