Effects of soil redistribution on soil properties in a cultivated Solonetzic-Chernozemic landscape of southwestern Saskatchewan

Abstract

. 1999. Effects of soil redistribution on soil properties in a cultivated Solonetzic-Chernozemic landscape of southwestern Saskatchewan. Can. J. Soil Sci. 79: 593-601. Although approximately 1.3 million ha of mixed Solonetzic -Chernozemic landscapes are cultivated in Saskatchewan, little information is available on the effects that agriculture has had on the quality of these soils. At our research site in southwestern Saskatchewan a clear landscape-scale pattern of soil distribution occurred. Regosolic and thin Chernozemic soils were associated with the long, gentle (2-5%) slopes and Solonetzic-influenced soils were associated with higher catchment area footslope and depressional positions. High rates of soil loss occurred throughout the landscape -overall a net soil loss of 31 Mg ha yr -1 was calculated using 137 Cs redistribution techniques. No net depositional sites were observed in the 45 sampling points in the landscape, suggesting that the site was dominated by wind erosion. The high rates of loss were consistent with very low levels of soil organic carbon storage (37 to 46 Mg ha -1 to 45 cm) at all slope positions in the landscape and with the occurrence of sub-soil features in the plough layer. The Solonetzic-influenced soils occupy 38% of the site and have high sodium adsorption ratios (from 18 to 38 in the B horizon) and high soil resistance values as determined with a penetrometer. For the Solonetz and Solodized Solonetz soils these growth-limiting properties occur immediately below the 10-cm plough layer and may constitute a largely irreversible decrease in their productive capacity. Même si quelque 1,3 million d'hectares de paysage à sol solonetzique-chernozémique sont mis en culture en Saskatchewan, on est peu renseigné sur les effets que l'agriculture a eu sur la qualité de ces sols. À notre antenne de recherches du sud-ouest de la Saskatchewan, nous avons observé une nette association de la répartition des sols avec la position dans le paysage, les régosols et les chernozems occupant les longues pentes douces (2-5 %), tandis que les sols de type solonetzique se retrouvaient dans les zones de captage important, en bas de pente et dans les dépressions. Des taux élevés de pertes en sol se produisaient dans tout le tracé du paysage: une perte nette globale de 31 Mg ha par année était calculée au moyen de techniques de redistribution du 137 Cs. Aucun emplacement à dépôt de sol net n'était observé dans les 45 points d'échantillonnage répartis dans le paysage: l'érosion éolienne exerçant un rôle dominant. Ces taux élevés de perte en sol concordent avec le niveau très bas de stockage du carbone organique dans le sol (37 à 46 Mg ha -1 dans la tranche de profondeur de 0 à 45 cm) observés à tous les emplacements dans le paysage. Ils concordent aussi avec la présence de caractères de sous-sol dans la couche de labour. Les sols à influence solonetzique, qui occupent 38 % du terrain, démontrent un rapport d'adsorption du sodium élevé (allant de 18 à 38 dans l'horizon B) et des fortes valeurs de résistance à la...

How Spatial Patterns of Soil Moisture Dynamics Can Explain Field‐Scale Soil Moisture Variability: Observations From a Sodic Landscape

“…Only the participating sites were able to support brush vegetation. Ultimately, the fact that Solonetzic soils are often found in association with Chernozemic soils over small spatial scales (Miller & Brierley, ; Pennock et al, ) results in a particularly heterogeneous landscape (Carter & Pearen, ; Pennock et al, ; Sandoval & Reichman, ). For instance, Carter and Pearen () found that some physical properties of Solonetzic soils, such as the thickness of the A horizon, exhibit little spatial dependence at distances greater than 5 m. Similarly, Sandoval and Reichman () report that infiltration rates into Solonetzic soils are also highly variable within short distances.…”

“…Soils belonging to the Soloneztic Order are often referred to more generally as sodic soils, and hereafter, we use the terms interchangeably. In the prairies, Solonetzic soils are typically found in catenas with soils of the Chernozemic Order (Miller & Brierley, ; Pennock et al, ). Solonetzic soils form from salinized parent material, rich in sodium salts (Pawluk, ).…”

“…The local field soil has been classified, based upon a single soil pit in the center of the study site, which was located at a high spot in the landscape, as a dark brown Solonetzic Chernozem, in which the B horizon exhibits some of the features of a Solonetzic soil, but the structure is not fully characteristic of soils belonging to the Solonetzic Order (i.e., weak solonization, lacking the distinct Bnt horizon necessary to be classified as Solonetzic soil). It is therefore likely that this site has soils with both Solonetzic and Chernozemic characteristics where soil heterogeneity is high and the low permeability Solonetzic B horizon is discontinuous or patchy across the landscape, similar to that of Pennock et al (1999). Peterson et al (2016) quantified the field-scale root-zone soil moisture at this site, using a cosmic ray neutron probe, combined with the neutron probe data reported here.…”

Chernozemic soils of Canada: Genesis, distribution, and classification

“…The catenary distribution of soil properties and taxa along hillslopes in hummocky and undulating Prairie landscapes has been often studied, in part because elsewhere it is rare to see members of three soil orders occurring within tens of meters of each other; indeed in Solonetzic-Chernozemic landscapes we can observe members of four orders over the same distance (Pennock et al 1999). The occurrence of different B horizon features, and the consequent occurrence of different subgroups along the catenary sequence, has been well established across these studies (Figs.…”