Given the importance of agroforestry systems (AFS) in mitigating the impact of agriculture on the ecosystems and environment, it is critical to understand the effect of plant species richness in diverse tropical AFS on their soil properties. The objective of this study was to evaluate the role of different AFS in the conservation of plant species richness, and their effect on soil physical and chemical properties. We compared plant species richness and soil properties among six AFS by sampling 63 plots in the humid tropics. Sampled AFS include: (1) home garden (HG), (2) shade trees in plantation (ShTP), (3) live fences (LF), (4) scattered trees in paddocks (ScTP), (5) grazing under plantation (GP), and (6) slash and burn agriculture (SBA). The vegetation community in each plot was recorded by scientific name and species richness was calculated. Soil samples were collected from 0 to 10 and 10 to 20 cm depth and analyzed for pH, organic matter (OM), nitrogen (N), phosphorus (P), electrical conductivity (EC), cation exchange capacity (CEC), and texture. The highest plant species richness was found in HG (125), ShTP (121), and ScTP (89), followed by GP (56), LF (35), and SBA (4). This richness of plant species influenced the soil N (r = 0.514, P = 0.028), P (r = 0.480, P = 0.514), and OM contents (r = 0.439, P = 0.067), as well as CEC (r = 0.402, P = 0.097), EC (r = 0.153, P = 0.543), and pH (r = 0.363, P = 0.115). The highest values of pH (6.6) and P (8.14 mg kg⁻¹) were observed in the species richest AFS, and the highest OM (10.8%), N (0.49%), and EC (0.26 µs/cm) were found in the SBA system that has been converted recently from forests. In the SBA, the high values of pH, OM, N, EC, and CEC were result of cutting and burning of plant biomass during the land-clearing process. It is concluded that AFS harbor a great diversity of plant species and can improve soil fertility, which is essential for developing sustainable agroecosystems. Further research is required to understand the effect of variation in AFS age on the overall soil health indicators.

鉴于农林业系统 (AFS) 在减轻农业对生态系统和环境影响方面的重要性，了解不同热带 AFS 中植物物种丰富度对其土壤特性的影响至关重要。本研究的目的是评估不同 AFS 在保护植物物种丰富度方面的作用及其对土壤理化性质的影响。我们通过对潮湿热带地区的 63 个地块进行采样，比较了 6 个 AFS 的植物物种丰富度和土壤特性。采样的 AFS 包括：(1) 家庭花园 (HG)、(2) 种植园中的遮荫树 (ShTP)、(3) 活栅栏 (LF)、(4) 围场中的零散树木 (ScTP)、(5) 种植园下放牧(GP)，(6) 刀耕火种农业 (SBA)。按学名记录各样地的植被群落，并计算物种丰富度。采集 0 至 10 和 10 至 20 厘米深度的土壤样品，并分析 pH、有机质 (OM)、氮 (N)、磷 (P)、电导率 (EC)、阳离子交换容量 (CEC) 和质地。植物物种丰富度最高的是 HG (125)、ShTP (121) 和 ScTP (89)，其次是 GP (56)、LF (35) 和 SBA (4)。植物物种的丰富度影响土壤 N ( r  = 0.514, P  = 0.028)、P ( r  = 0.480, P  = 0.514) 和 OM 含量 ( r  = 0.439, P  = 0.067) 以及 CEC ( r  = 0.402，P  = 0.097），EC（r  = 0.153，P  = 0.543）和 pH（r  = 0.363，P  = 0.115）。在物种最丰富的 AFS 中观察到最高的 pH 值 (6.6) 和 P (8.14 mg kg ^-1 )，并且发现最高的 OM (10.8%)、N (0.49%) 和 EC (0.26 µs/cm)最近从森林转变为 SBA 系统。在 SBA 中，pH、OM、N、EC 和 CEC 的高值是土地清理过程中砍伐和燃烧植物生物质的结果。结论是，AFS拥有丰富的植物物种多样性，可以提高土壤肥力，这对于发展可持续农业生态系统至关重要。需要进一步的研究来了解 AFS 年龄的变化对整体土壤健康指标的影响。