Managing natural resources for their human values

© 2015 Smith et al. Species composition and structure are important properties that can influence the extent to which people value a natural element. Hence these two properties can provide a means to directly manage natural elements to meet values-based goals. With this principle in mind, we studied soil seed bank assembly in two wetland vegetation elements recognized for their science/education, opportunity and system benefit values. Because seed banks drive the composition and structure associated with a vegetation element, which in turn influence human value satisfaction, variance partitioning modeling was used to determine which combination of filters best described patterns in the seed bank beta diversity. A combination of abiotic (soil permeability and soil salinity) and spatial filters with several interactions were the best descriptors of beta diversity, particularly for one vegetation element (wetland 1). Within the remaining vegetation element (wetland 2), a much greater diversity of weed species was observed. Based on the different patterns in diversity, including the links between these patterns, particular filters, and associated processes, we propose that the two vegetation elements, despite their close proximity to each other, are on diverging reassembly pathways. To manage the vegetation elements such that they maintain their values, we suggest hydrological processes are controlled to ensure that soil salinity does not increase dramatically. Dramatic increases in salinity will decrease element value by reducing vegetation diversity and plant community structure. We also stress the importance of understanding and managing processes that effect within-element dispersal and invasion by weeds. Here we demonstrate a general approach to inform the management of natural resources. It is important to identify, understand, and manage the filters (and associated processes) that restrict observable patterns in the properties that influence element value, sensu rules to manage the human valuation of natural elements.