Laura Turnbull and I have just published a paper in Ecological Indicators looking at how ideas of hydrological and sediment connectivity can be used to understand shrub encroachment in drylands, in particular using some of our data from the Sevilleta LTER site.
You can freely download the paper from https://authors.elsevier.com/a/1Y6NP,XRNLZ2~Y until 12th January 2019 or feel free to email me for a copy.