ABSTRACT Western Amazon has the highest forest biodiversity in the world; however, farming, pasture, or subsistence farming has cleared extensive forest areas, impacting soil quality. This study evaluates the variations in soil quality indicators such as organic carbon (OC), NH4+, available P, soil texture, and pH, taking into account changes of land use from forest to disturbed areas in four different landscape positions: plains, peneplains, piedmont, and periandes piedmont. We used three vegetation cover maps of 1990-2000-2008 and 1,820 soil samples in an estimated area of 40,000 km2. Cokriging and regression kriging of each edaphic attribute and maps of land use were crossed. Analysis of variance for each landscape position was applied in order to identify significant differences in soil quality indicators between different land use categories (forest and disturbed areas). Results suggest changes in biogeochemical soil dynamics. We reported statistically significant reduction in the percentage of OC for disturbed areas and an increase in available P, which is remarkable. NH4+ stocks were lower for disturbed areas; however. In piedmont and periandes piedmont landscapes, forests presented the highest concentrations of OC (3.99 ± 1.1 and 5.06 ± 1.41, respectively) in comparison to disturbed areas (3.56 ± 0.87 and 3.98 ± 1.41, respectively). Changes in soil quality main indicators suggest a potential drop in ecosystem services production for the western Amazon of Ecuador. Management decisions should consider sustainable land use strategies oriented to maintain the resilience of soil quality indicators.

中文翻译：

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土地利用变化对亚马逊西部森林景观土壤质量指标的影响

摘要 西部亚马逊拥有世界上最高的森林生物多样性；然而，耕作、放牧或自给农业清除了大片森林，影响了土壤质量。本研究评估了土壤质量指标的变化，如有机碳 (OC)、NH4+、有效磷、土壤质地和 pH 值，同时考虑了从森林到受干扰地区在四个不同景观位置的土地利用变化：平原、平原、皮埃蒙特和佩里安德斯皮埃蒙特。我们使用了 1990-2000-2008 年的三张植被覆盖图和 1,820 个土壤样本，估计面积为 40,000 平方公里。每个土壤属性和土地利用地图的协同克里金法和回归克里金法交叉。应用每个景观位置的方差分析，以确定不同土地利用类别（森林和受干扰地区）之间土壤质量指标的显着差异。结果表明生物地球化学土壤动力学的变化。我们报告了扰动区域 OC 百分比的统计显着降低和可用 P 的增加，这是显着的。受干扰地区的 NH4+ 存量较低；然而。在山前和 periandes 山前景观中，与干扰区域（分别为 3.56 ± 0.87 和 3.98 ± 1.41）相比，森林的 OC 浓度最高（分别为 3.99 ± 1.1 和 5.06 ± 1.41）。土壤质量主要指标的变化表明厄瓜多尔西部亚马逊地区的生态系统服务产量可能下降。