Deep Roots: Understanding geochemistry and nutrient mobility in vineyard soils to enhance soil management practices at Pelee Island Winery

点击翻译按钮获取中文摘要

Over 160 years of winemaking on Pelee Island have demonstrated that grapes thrive on the clay-rich soils known as the Toledo clay that dominate the island. The winery is investing in research that will direct their soil management strategies to increase the production and quality of their grapes and the island-grown compost. In addition, the winery wishes to identify the unique soil properties that contribute to the terroir of this region, with the hope of being declared an appellation in the future. Currently the vineyard tests the major element content of the top 40 cm of the soil every few years but deep vine roots can access nutrients from depths of 6 m and little is known about the impact of weathering of both soil and bedrock minerals on the nutrients available in the soils. This project will identify the geochemical controls on nutrient availability over the entire rooting depth in the vineyards on Pelee Island. The specific objectives are to: 1) determine the role that bedrock geology plays in soil composition, 2) assess how mineralogy and crop amendments influence nutrient availability over the entire depth of the soil and 3) determine whether the trace elements in the soil are transferred to the grapes. Variations in mineralogy, depth to bedrock, organic matter content, pH and element mobility over the depth of the entire soil profile may explain some of the observations made by the winery manager such as: why plants on the deeper parts of the Toledo clay grow with more vigour, why vineyards treated with island-grown alfalfa compost are rich in magnesium and why grape vines that typically prefer well drained soils thrive on the clay-rich soils of Pelee Island. The results of this project will enable Pelee Island Winery to enhance soil management on a field by field basis in order to improve nutrient availability to the plants (e.g. adding amendments or changing soil pH), develop future planting strategies (e.g. variations in soil quality and depth across the vineyard may suit different grape species or root stocks), and market their premium wines that embody the unique terroir from this region with the hope of gaining appellation status.****