Many studies in South Africa have examined the impacts of alien plants on ecosystems, but none have assessed the impact of guava (Psidium guajava L.) invasion on soil properties. In this study, soils underneath guava‐invaded sites were assessed to determine if they had different soil physico‐chemical properties (pH, P, C, N, Na, K, Ca, Mg, moisture, penetration resistance, infiltration and water repellency) as compared to soils underneath uninvaded sites. Comparisons were made from three different sites over three autumn months. Results show that soil pH was significantly (p < 0.005) higher underneath uninvaded than guava‐invaded sites. Soil P was three times higher underneath guava‐invaded as compared to invaded sites. The soils collected underneath guava‐invaded sites had a significantly (p < 0.001) higher moisture content and were less compact but more repellent than soils from the uninvaded sites. Infiltration rate was significantly (p < 0.001) higher in the uninvaded than the guava‐invaded sites. The study concludes that guava invasion alters some soil properties, thus creating favourable conditions for its growth and making it potentially more invasive. From a management standpoint, guava removal is encouraged; however, given guava's socio‐economic importance more research on cost and benefits is required.

中文翻译：

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南非林波波的外来番石榴入侵对土壤性质的影响

南非的许多研究都研究了外来植物对生态系统的影响，但没有一项评估番石榴（Psidium guajava L.）入侵对土壤特性的影响。在这项研究中，对番石榴入侵地点下面的土壤进行了评估，以确定它们是否具有不同的土壤理化特性（pH，P，C，N，Na，K，Ca，Mg，水分，耐渗透性，渗透性和防水性）与未入侵地点下方的土壤相比。在三个秋季的月份中，从三个不同的地点进行了比较。结果表明，土壤pH值显着（p <0.005）低于未入侵番石榴的位置。番石榴入侵下的土壤磷比入侵地点高出三倍。在番石榴入侵地点下收集的土壤的 水分含量显着较高（p <0.001），并且比未入侵地点的土壤致密但具有拒水性。 在未入侵地区，渗透率显着高于（p <0.001）在番石榴入侵地区。研究得出的结论是，番石榴入侵会改变土壤的某些特性，从而为其生长创造有利条件，并使其具有更大的入侵性。从管理的角度出发，鼓励去除番石榴。但是，鉴于番石榴的社会经济重要性，需要对成本和收益进行更多的研究。