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Posts

02 December / / Research / Interest


This analysis was prepared by the Fynbos Node of the South African Environmental Observation Network (SAEON).

Here we present the record of stream flow rates for the Langrivier catchment and rainfall from the Dwarsberg weather station in the Jonkershoek Valley for the period January 1961 to the end of November 2019. The Dwarsberg weather station is at 1214 metres above sea level on the boundary of the catchments of the Eerste, Berg and Sonderend rivers and is a good indicator of rainfall feeding the Berg and Theewaterskloof dams.

21 November / / Interest / Research
This is an updated quick and dirty analysis of the CapeNature fire database (spanning 1927 to 2018) to see if the major drought that is currently being experienced in the Cape Floristic Region has had any impact on the occurrence or extent of wildfires. I first ran this analysis in 2017 and have been updating it every year. Wildfires are an essential component of fynbos, but components of the fire regime such as return interval need to be within certain bounds of variability to maintain healthy ecosystems.
31 October / / Research / Interest
Update! We submitted this project for the UN Global Pulse Data for Climate Action competition and won the Thematic Award for Climate Mitigation at COP23 in Bonn, Germany! :) Recent advances have seen the development of near-real time monitoring tools that report on the state and changes in vegetation based on satellite observations, e.g. globalforestwatch.org. These tools are hugely valuable for managing ecosystems and for developing the long term records required to understand ecosystem dynamics and trajectories of change.
09 October / / Research
This is just a very quick post to point out a Smartphone App I’ve been working on that allows citizen scientists, field rangers and landowners to map threats to and impacts on biodiversity. These include a range of impacts from invasive alien plants, plant mortality, landslides or illegal vegetation clearing, etc. NOTE: Unfortunately, release of the app has been released due to location accuracy issues with the app development platform I’ve been using see this post for details.
14 September / / Research / R Tutorials
This is based on data collected when I took students from SAEON’s Graduate Student Network into the field to introduce them to Fynbos and to show them a bit of the science I’m working on. To make things more interesting, I got them to help me test a smartphone app I’ve been developing (“VeldWatch”) that can be used to map any impacts on natural ecosystems observed in the field, like invasive species, plant mortality, etc.
This is a study recently completed by one of my MSc students, Annabelle Rogers, who I co-supervised with Prof Ed February and Glenn Moncrieff. We’re busy writing it up for publication, but here’s a little preview. The study was inspired by this great paper published by Dr Coert Geldenhuys in 1994, explaining how fire determines the distribution of forests in the Southern Cape. You can also read about it, and get a nice intro to our forests, in this interesting SA Forestry Online article.
21 April / / Research
After a decade of hard slog I finally had a study come out this week showing that increasingly prolonged periods of severe hot and dry weather during the first summer after wild fires is inhibiting vegetation recovery and causing loss of plant diversity in the Fynbos. If you don’t have access to the journal through the link above, I made a short video explaining the general gist. Otherwise shoot me a message and I’ll send it to you.
This is a quick primer on how to handle MODIS and Landsat NDVI data from Google Earth Engine (GEE) in R. It’s primarily for my Honours student, Hannah Simon, but I thought why not make it public for all to share? I first posted the MODIS section and had Hannah play with the Landsat data as a learning exercise, so full credit to her for the Landsat code. For a general introduction for many of the functions used and handling spatial data in general see A Primer for Handling Spatial Data in R posted previously.