Quinoa biomass production capacity and soil nutrient deficiencies in pastures, tree plantations and native forests in the Andean Highlands of Southern Ecuador

La Granja: Revista de Ciencias de la Vida

David Paré¹  Gustavo Chacón²  Daniel Gagnon³ 

[1] Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre;Universidad del Azuay;University of Regina;

关键词: agricultural potential;    nutrient deficiency;    volcanic soils;   

DOI  :  10.17163/lgr.n24.2016.02

来源: DOAJ

【 摘 要 】

In the high Andes of Ecuador, although expanding agricultural practices and overgrazing have had negative impacts on soil fertility, few investigations have been conducted to identify which practices are most likely to reduce fertility. Quinoa (Chenopodium quinoa Willd.) was grown in soils from native forests, Nf; pastures, Pa; Eucalyptus globulus Labill. plantations, Eg; and Pinus patula Schlecht. plantations, Pp. A bioassay study was conducted using a randomized block design with control (C), ammonium nitrate (N), triple superphosphate (P), and combined N and P (N+P) fertilizer treatments. On soils from Pp, quinoa mortality was 100% in N, 88% in C, 63% in N+P and 0% in P; P enhanced growth the most; quinoa biomass attained only 0.1 g/pot and had a P content of 0.7 mg/pot. N+P enhanced quinoa growth the most on soils from Nf, Pa and Eg. Here, quinoa biomass (g/pot) averaged 0.1 in C, 0.4 in N, 1.6 in P and 7.2 in N+P; P content (mg/pot) averaged 0.9 in C, 0.6 in N, 12 in P and 38 in N+P. In all soils, PO4- was the principal limiting factor. K deficiencies and Al toxicity probably occurred only in Pp soils. This study suggests that the studied soils cannot support production of quinoa crops without additions of combined fertilizers containing P and K as the principal elements. Pp have the least fertile soils, presumably resulting from a longer history of use after pasturing in addition to the pine effect itself.

【 授权许可】

Unknown