The difference between Rioja Alta and Alavesa lies in their respective soil compositions and altitudes. Rioja Alta, as the name suggests, is located at higher altitudes compared to Alavesa. The soil in Rioja Alta is a combination of alluvial soil, calcareous clay, and ferruginous clay. This diverse soil composition contributes to the unique characteristics of the wines produced in this region.
The alluvial soil in Rioja Alta is formed by the deposition of sediments brought by rivers. This type of soil is generally fertile and provides good drainage for vine roots. The calcareous clay soil, on the other hand, is rich in limestone, which imparts minerality and complexity to the wines. The ferruginous clay soil contains iron oxide, which can give the wines a distinct color and contribute to their overall structure.
In contrast, the soil in Rioja Alavesa is mainly characterized by limestone and clay-rich terraces. The limestone soil is known for its ability to retain moisture and provide a steady supply of nutrients to the vines. The clay-rich soil also helps with water retention, which is crucial in a region with a Mediterranean climate like Rioja. These soil characteristics in Alavesa contribute to the elegance and finesse often associated with the wines produced here.
Another notable difference between Rioja Alta and Alavesa is the altitude. Rioja Alta is situated at higher elevations, which can have a significant impact on the grapes grown in this region. Higher altitudes generally result in cooler temperatures, which can lead to slower ripening of the grapes. This extended growing season allows the grapes to develop more complex flavors and maintain good acidity levels. In contrast, Rioja Alavesa, with its lower altitudes, may experience slightly higher temperatures, resulting in a slightly different flavor profile in the wines.
To summarize, the main differences between Rioja Alta and Alavesa lie in their soil compositions and altitudes. Rioja Alta has alluvial soil, calcareous clay, and ferruginous clay, while Rioja Alavesa is characterized by limestone and clay-rich terraces. The higher altitudes in Rioja Alta contribute to a cooler climate, allowing for slower ripening and more complex flavors in the wines. On the other hand, Rioja Alavesa's lower altitudes may result in slightly higher temperatures and a different flavor profile.