Green roof ecosystems are increasingly used to compensate for the loss of green space and biodiversity in many cities. Their ecosystem services and the performance of the aboveground biota have been extensively studied, e.g. pollinators and plant community composition (see page by Kzasiak). However, the functioning in the largest and most indispensable component of green roofs, namely the soil substrate, has long been overlooked.
Conservation and Restoration
The success of prairie and woodland restorations is typically assessed using measures of diversity and productivity of the aboveground plant community. However, this approach misses an important component to plant growth: the belowground system and its capacity to support productive ecosystems. The concept of soil quality includes assessment of soil properties (e.g. nutrients, texture) and processes (e.g. microbial activity) as they relate to ability of soil to function effectively as a component of a healthy ecosystem.
Global estimates show that soils store more carbon than the atmosphere and plants combined. Despite the obvious importance of soils in global carbon cycling, there remain critical gaps in our knowledge of the sequestration of long-lived carbon stores. Fungi constitute a major portion of belowground biomass and thus the decomposition of their dead tissues (or necromass) should be an important contributor to soil carbon sequestration.
Of the Garden's 385 acres, nearly one-quarter (81 acres) is water. A 60-acre system of lakes winds throughout the gardens and research facilities. About 5.7 miles of shoreline encircles the Garden's lakes, so it is not surprising that the Garden is keenly interested in protecting its shoreline soils and enhancing aquatic habitat.
How genetically diverse are ex situ collections of rare and endangered plant species? It is important to understand the genetic diversity held by ex situ collections and develop tools and techniques to increase this diversity wherever possible. This is important because ex situ collections that are not genetically diverse are of limited value to the long-term conservation of the species.
Native plants are those flowers, grasses, shrubs, and trees that are indigenous to a geographical region. Invasive species like buckthorn are those that, when introduced to a new location, can spread prolifically, competing with native species for resources and eventually dominating the landscape. Some invasive species were popular ornamental plants used in landscaping. Chicago Botanic Garden scientists researching invasive species have discovered that buckthorn was not nearly as pervasive in our region in previous centuries as it is today.
The Chicago Botanic Garden’s Dixon National Tallgrass Prairie Seed Bank continues to collect and preserve germplasm of native plant species from the Upper Midwest. In 2014, we added 356 accessions to the bank. Our total holdings include 3,336 accessions of 1,479 species. We also collected seeds on contract from the U.S. Forest Service, and we continue to be an active partner in the national Seeds of Success (SOS) program. Megan Haidet, hosted by the U.S. Department of Agriculture Bureau of Land Management, coordinates all SOS activities.
Garden scientists and graduate students have been working on conservation- and restoration-related research in the arid regions of the western United States since 2002.
An important goal of any reintroduction is to provide sufficient genetic variability to buffer against changing selection pressures and to ensure the long-term survival and continued evolution of a species. Genetic erosion during the creation of a reintroduced population can have a large impact on long-term success.