Fieldwork instruments part 3

Video transcript

Hello again. In this video we're going to be measuring three abiotic factors that are to do with the landscape. 

The first factor is the slope or the gradient. I'm standing on a hillside that slopes down behind me and to measure its slope I'm going to be needing one of these. Now this is called a clinometer or an inclinometer. If you pull the trigger the needle can move smoothly and once you release the trigger it holds and reads off the dial what the slope the instrument was held at was. 

Now it's important when you're using a clinometer to remember that you have to aim it, a little bit like in the movies, to get an accurate result. So to record the mean slope of this hillside we need two people of roughly equal height, now I'm by myself so I've got to problem-solve here. I know that my height on that tree down there comes up to a certain mark which I established before. If I aim at that mark now, pull the trigger, I wait for the needle to stop moving, I release the trigger while I'm still aiming and I come back to read the scale. In this case slope was around nine degrees. 

The aspect is the way the hillside faces. Now the hillside behind me is really uneven. We've got a lot of sandstone sticking out, we've got a lot of eroded areas so you have to make a call what the average direction that the hill's facing is. In this case I'm calling it right behind me. 

Now to measure the aspect we use a compass. Got a compass here. You need to hold it flat. Work out which way the red magnetic north arrow is pointing, in this case this direction. So if I put that down and I know that's north, that's south, and it looks like we're just 45 degrees to the left of south. So in this case we're looking at south-east for the aspect. 

Now the last factor that we want to determine to do with the landscape is the position. Now this can be recorded in different ways, on a map it can be eastings and northings but most commonly what we use is something called latitude and longitude. 

To do that you can use a handheld GPS or most people have got apps on their smartphone which will tell you the latitude and the longitude. In my case I'm using something that everybody should have called the emergency plus app which will tell you where you are and call an ambulance even if you're out in the bush. Let's have a look at that close-up. 

So there you go everybody, that's how we measure the three abiotic factors of slope, aspect and position. See you soon.

End of transcript.