Lesson 7: How to approximate the volume of a tree based on Denzin's formula and how to calculate a form factor? #unigöttingen #forestinventory #forestmensuration
Пікірлер: 26
@gurwin86 Жыл бұрын
Thank you very much for detailed formula.
@ayeshasaddiqa6218 Жыл бұрын
Thank you Professor
@madhurimapurkait12002 ай бұрын
Sir, can you please suggest me which one is the best laser range finder?
@binisadeba71762 жыл бұрын
Thank you for your clear video teaching how to get form factor of a tree. let me ask one question that is it possible for natural forest trees found in Africa?
@andrehoffmann24205 ай бұрын
Grüße geht raus an alle Waldwissenschaftler aus Freiburg!
@ibbud6382 Жыл бұрын
mantap
@raoazeem81922 жыл бұрын
👍
@claudiagottstein924410 ай бұрын
Thank you for the detailed information! How do I correctly cite Denzins formula?
@forestinventory10 ай бұрын
Unfortunately I don't have the original copy from 1929. In Kramer & Akca I found this citation: Denzin 1929. Schätzung der Masse stehender Waldbäume. FA, 382-384.
@claudiagottstein924410 ай бұрын
@@forestinventory Thank you!
@claudiagottstein924410 ай бұрын
@@forestinventory This source includes the correction for norm height, right?
@piyushgautam7058 Жыл бұрын
Sir 49.3 is the diameter or circumference. The way it is measured shows that its circumference. If you calculated the diameter by circumference please tell about that also. DBH = GBH/3.14 THANKS
@forestinventory Жыл бұрын
We are here using a diameter tape, which is very common in forestry. It does exactly what you mentioned, the scale is divided by pi. This means you can directly read the diameter. Check out video on dbh measurement.
@r.lalrinhlua7402 Жыл бұрын
How do you directly take the diameter reading?
@forestinventory Жыл бұрын
Edwine is here using a diameter tape with pi scale from which you can directly read the diameter. Watch our video on tree diameter measurement to learn how...
@gurwin86 Жыл бұрын
@@forestinventorythank you very much.
@billwesterman4583 Жыл бұрын
Do you understand the difference between diameter and circumference?
@forestinventory Жыл бұрын
If you are not familiar with a diameter tape which has a pi scale, see our video on diameter measurement. It's right that Edwine measures a circumference, but on the tape he can directly read the diameter (assuming a circular shape).
@tombartlett84033 ай бұрын
Is this calculating the volume of the entire tree (branches? Crown?) or up until the timber height? Thanks
@forestinventory3 ай бұрын
Denzin's formula is for the whole tree including crown and branches down to a diameter of 7 cm. In fact, if you recalculate the form factor you will see that Denzin implicitly assumes a factor of 0.5 for a tree of 25m standard height (assuming you calculate volume = basal area * tree height * form factor). Form factors for commercial volume are higher, like 0.8.
@tombartlett84033 ай бұрын
@@forestinventory Thank you, so timber height. Should I be using the timber height (up to 7cm top diameter) when using Denzin's method for broadleaves, such as oak. Or, is total height, base to tip, used for all trees? I've used this for several species and the form factors vary from 0.48 to 0.65, using the 25m standard height for 'volume correlation percent'. Is the Norway spruce in this video not a commercial volume? My understanding is spruce form factors are about 0.6? This single tree volume method can be used for all trees, open grown or in a plantation? Should you ever change the 25m standard height? E.g =(DBH^2/1000)+(DBH^2/1000)*(height-)*3%
@forestinventory3 ай бұрын
Denzin is using the total tree height from base to tip to adjust the height depending form factor. The result is always total volume (up to 7cm), which is called "Derbholz" in German. Later he also suggested some species specific corrections, but they differ only slightly from the overall 3% per meter height difference to 25m. But his formula is just a fast and simple approximation since form factors might vary with site conditions. I think for trees growing in open areas the h/d relation might be very different. Form factors for total height and volume for spruce in Germany vary from 0.38 to 0.57 depending on tree age and site quality.
@KK-cx1kb2 жыл бұрын
I need Eucalyptus tree volume formula with form factor for calculating tree volume
@arupm7949 Жыл бұрын
With due respect sir, I think the diameter you measured was actually 49.3 inches and not in cm. When you convert it to cm, it becomes 125.2cm or 1.25m. The height is 28.8m. Now applying quarter girth formula here, (1.25×1.25×28.8)/16, the calculated volume becomes 2.81 cu.m . This formula is 78% correct which gives buyers advantage during sawing of round timber. I am forest officer from India and here we follow this. Now, if we calculate cylinder volume, it becomes approximately 3.6 cu.m. Now, the form factor is (2.81÷3.6) = 0.78.
@lutzfehrmann5219 Жыл бұрын
Hi Arup, dbh was measured in cm here! Converting 43,9cm to inch would be 19,4inch.