The importance of Small Streams

Last Friday, Dr. John Rex gave us the presentation on ‘Small Streams and Big Dreams: Watershed Management Challenges and Opportunities’. His presentation consists two main parts, first, he introduced the concept about the small stream, and then he talked about the climate change projections and some watershed management challenges.

Since Dr. John Rex represented lots of information, there is much new information I learnt from his presentation. The small streams that he focused on study are those with a bank full width less than three meters. Small streams can be intermittent, ephemeral, or perennial. Before his presentation I thought small streams are not important, however, they actually play significant roles in watershed hydrology. They are overlooked, but they are important because they are numerous, they influence downstream condition, they provide migration corridors, they commonly encounter during development. Lastly, they are sensitive. Then, he introduced the study methods of analyzing the shade, air and the stream temperature response of the stream.  He also introduced the FREP routine riparian effectiveness evaluation protocol. The results show that headwater and larger streams low to recover from extensive harvesting, upstream riparian harvest smaller than 30% of the channel length will not have negative effects on downstream.  In the second part, he introduced the climate change (global warming), forest cover change, beetle and salvage harvesting will have a large impact on small streams. Lastly, he talked about the big dreams that including active adaptive management, collaborate with industry, academia, government and stakeholders.

The particular aspects I found out about his presentation interested is that the harvest trees around streams will cause higher erosion of the land, and will increase the stream temperature due to the less cover of the trees from the sun.

Overall, I think Dr. John Rex did a very good presentation. He explained the concepts thoroughly and easily to understand. He has a good skill to explain the concepts with graphs and pictures. There are many presentation skills that I can learn from him; however the content of his presentation is not relevant to my Master’s research.

Many questions were asked of him. He answered the questions very well. If I was given the opportunity, the question that I would ask for him is that, how the wood harvesting affected the small streams in the past twenty years of his study.