POWRE: Forging International Collaborations to Investigate Mechanisms of Accelerated Phosphorus Cycling in Native Amazonian Agroecosystems

麦格拉思9973472磷的有效性限制了整个热带地区的植物生产力，包括南美洲亚马逊盆地的大多数土壤。 有一些植物，如经济上重要的桃棕榈（Bactris gasipaes），仍然相对生产力诊断为P-贫土壤，虽然这些植物可能增加P-有效性的手段知之甚少。 有人建议，这种植物可以用来增加磷的可用性，在同一系统中生长的其他植物。 该项目将确定和测量一些亚马逊本地物种，如桃棕榈，生长在贫磷土壤中可能使用的“较少可用”的磷形式。 该研究还将通过检查这些植物根部周围土壤化学的变化，确定桃棕榈和其他亚马逊树木是否适应利用否则“不可用”的土壤磷形式。 在巴西亚马逊地区的实地研究中，还将探讨使用适应于利用较少可用形式的磷的植物来增加生长在缺磷生境中的相关作物的磷可用性的意义。 从这些研究中获得的信息将使我们进一步了解一些植物如何能够在看似缺磷的条件下加速磷循环，以及它们如何用于更可持续地管理土地，因为快速的土壤耗竭是导致热带地区森林砍伐和土地清理的主要因素。 与其他机构合作开展此类研究将有助于确保研究结果适用于更广泛的环境。

McGrath 9973472 Phosphorus availability limits plant productivity throughout the tropics, including in most soils of South America's Amazon Basin. There are some plants, such as the economically-important peach palm (Bactris gasipaes), that remain relatively productive in diagnostically P-poor soils, although the means bywhich these plants may increase P-availabilty are little understood. It has been suggested that such plants could be used to increase P-availability to other plants grown in the same system. This project will identify and measure "less available" forms of P potentially used by some native Amazonian species, such as peach palm, growing in P-poor soils. The study will also determine if peach palm, and other Amazonian trees, are adapted to utilize otherwise "unavailable" forms of soil P, by examining changes in soil chemistry around the roots of these plants. The significance of using plants adapted to utilize less available forms of P to increase P availability to associated crop plants growing in P-deficient habitats will also be explored in field studies in the Brazilian Amazon. The information gained from these studies will further our understanding of how some plants are able to accelerate P cycling in seemingly P-deficient conditions, and how they can be used to manage land more sustainably, since rapid soil depletion is a major factor contributing to deforestation and land clearing in the tropics. Conducting such research in collaboration with other institutions will help ensure that the results are applicable to a wider range of environments.