Search found 3 matches

Return

Taking The Survey Into The Sky

Point cloud mapping can also be used for more than just volume/surface area calculation of trees. It can also be used as a tool to measure entire forests.

Using an airplane and weather balloon, a few friends and I have been mapping the mighty Fetzer Oak from above. The Fetzer Oak is tallest and possibly largest known valley oak in California. Height it 153 feet, dbh 9 feet. The trunk bifurcates at about 30 feet.

Using 1) weather balloon mounted servo controlled GoPro2 with TP360 and 2) airplane fly-over with side door removed and hand held DSLR, we generated a series of photo-sequences to use in the photo-bundling software to produce a 3D point cloud of the general Fetzer Oak area. See attached.

From this overhead point cloud all the heights and of every tree visible in the cloud can be quickly and accurate measured without actually needing to go there. If you zoom in on the screen captures from Meshlab you'll see the measuring rod tool from Meshlab Version 1.31 where I am measuring Fetzer Oak at 154 feet. Actual height 153.12 feet.

Not only can I measure all the trees in the point cloud but I can also measure the height and size of all the other visible structures including volume of the large barn to the Northern East.

This aerial photo-bundling system to measure forest canopy shows much promise for cloud mapping large tracts of forest to search for the tallest trees just like a LIDAR search. Similar type point clouds are generated but with the photo-bundling method you get a nice set of pictures that link up with the point cloud. These linked photographs can be used to identify species and tree health.

The cost of mapping forests with this new approach vs. tradition LIDAR is now being investigated. I'll have more updates later as we scan larger tracts of forest.

Michael Taylor

WNTS VP
landmarktrees.net
California Big Trees Coordinator For American Forests
by M.W.Taylor
Mon Jun 25, 2012 3:50 pm
 
Jump to forum
Jump to topic

The world's most biomass-dense forests

NTS,

I made a literature search for the most biomass-dense forests on Earth. The forest types whose highest values are over 1000 tons/hectare have been listed below. I have named the forest types after the tree species with most biomass, with the exception of the last type where the biomass distribution between the two dominant species has not been specified. In all other types the named species have over twice the biomass of the second most important species. Other species may be more numerous, e.g. in the Sequoiadendron stand, Abies lowiana (= A. concolor var. lowiana ) is much more numerous but the former contains much more biomass. It is well known that Sequoia sempervirens forests are the most biomass-dense but it is less well known that the best Eucalyptus regnans stands are not far behind, one factor being about 25% higher wood density. Only above-ground live biomass is included.

biomass.jpg
The biomass values are not fully comparable. In some stands (especially S. sempervirens and Picea - Tsuga ) the biomass of all the components, including tree leaves and herbs, has been calculated. In some stands (e.g. A. procera , Pseudotsuga and Sequoiadendron ) only the stem biomass is included. In a few stands (e.g. E. regnans ), it is difficult to say which components have been included, therefore I did not make any adjustments. Anyway, most of the biomass is in the tree stems (in the case of the Picea - Tsuga stand 88%), so the stem biomasses should be relatively close to the total biomasses. In Agathis australis , a much higher proportion of the biomass is in the branches; anyway, the value for the Agathis stand includes branches, too. In three cases, only stem volume was given; for them, I calculated biomasses by multiplying the volumes by the wood densities I found on the Internet, mainly from source #10. Those values are shown in italics . The reliability of the sources may also differ.

For the Picea - Tsuga type, I averaged the biomasses of the two most massive 0.4 ha plots in the same location, because I wanted the stands to have, if possible, at least ~1 ha sample area to be comparable. If only the most massive plot is used, the value is 1078 t/ha.

Goat-forest2.jpg
My list may well be affected by accessibility of information. A further candidate for the list could be, for example, the Taiwania - Chamaecyparis forests of Taiwan. Other Eucalyptus species, like E. delegatensis , could also make the list.

It is well known that although tropical rainforests have much higher productivity they are not as biomass-dense as the western coniferous forests. However, the best stands are not far from making the list: the most massive value I have found is 873 t/ha for lowland evergreen dipterocarp rainforest in Sebulu, East Kalimantan. The value has been achieved by a very exact destructive sampling, though the sample area is only 0.125 ha (11).

For comparison, values for the eastern US and Europe would be useful. The highest value I have found for Europe is 788 t/ha. The site is Cozzo Ferriero Reserve, an almost pure Fagus sylvatica forest at 1700-1750 m a.s.l. in southern Italy. The site has been undisturbed since about 1930. Wood volume of 1383 m3/ha has been reported, though the plot size is only 0.16 ha (14). I used wood density 0.57 g/cm3 (15).

A note about the significance of high biomass values: It is too easy to draw the conclusion that an extremely biomass-dense forest is a place "full of life". However, most of this biomass is dead wood inside the tree boles where its significance to other organisms (apart from loggers and big tree enthusiasts) is limited.

If anybody has additions or corrections, please post them here.

Sources:

1 Van Pelt, R. (2014). Unpublished data.

2 Keith, H., Mackey, B. G. & Lindenmayer, D. B. (2009): Re-evaluation of forest biomass carbon stocks and lessons from the world's most carbon-dense forests .

3 Fujimori, T., Kawanabe, S., Saito, H., Grier, C. C. & Shidei, T. (1976): Biomass and Primary Production in Forests of Three Major Vegetation Zones of the Northwestern United States . J. Jap. For. Soc. 58 (10).

4 Silvester, W. B. & Orchard, T. A. (1999): The biology of kauri ( Agathis australis ) in New Zealand. Production, biomass, carbon storage, and litter fall in four forest remnants . New Zealand Journal of Botany , Vol. 37 : 553-571.

5 Dean, C., Roxburgh, S., Mackey, B. G. (2003): Growth modelling of Eucalyptus regnans for carbon accounting at the landscape scale. In Amaro, A., Reed, D., Soares, P. (eds.) Modeling Forest Systems . CABI, Wallingford. Citation in 2

6 Van Pelt, R. & Franklin, J. F. (2000): Influence of canopy structure on the understory environment in tall, old-growth, conifer forests . Can. J. For. Res. 30 : 1231–1245.

7 Herzog, W. (1989): Aufbau und Entwicklung von Tannenwäldern (Abies magnifica) in den Hochlagen der Sierra Nevada (Kalifornien). Forstarchiv 60 , 198-203. Citation in Schütt, P. & Lang, U. M. (2008): Abies magnifica. In Schütt, Weisgerber, Schuck, Lang, Stimm & Roloff: Lexikon der Nadelbäume . Nikol.

8 Mine, K. (1951): Great Cryptomeria stand at Kaneyama. Akita Regional Forest Office. Citation in Fujimori, T. (1977): Stem biomass and structure of a mature Sequoia sempervirens stand on the Pacific Coast of northern California . Journal of the Japanese Forestry Society 59 : 435-41.

9 Smithwick, E. A. H. et al. (2002): Potential upper bounds of carbon stores in forests of the Pacific Northwest . Ecological Applications , 12 (5), pp. 1303–1317.

10 Wood Density Database

11 Yamakura, T., Hagihara, A., Sukardjo, S., Ogawa, H. (1986): Tree size in a mature dipterocarp forest stand in Sebulu, East Kalimantan, Indonesia . Southeast Asian Studies 23 :452–478.

12 http://www.youtube.com/watch?v=K0pQbfVGuvg

13 Schmidt, P. A. (2002): Bäume und Sträucher Kaukasiens, Teil 1: Einführung und Gymnospermae (Nadelgehölze und sonstige Nacktsamer). Mitt. Dtsch. Dendrol. Ges. 87 , 59-81.

14 Calamini, G. et al. (2011): Stand Structure Attributes in Potential Old-Growth Forests in the Apennines, Italy. L’Italia Forestale e Montana 66 (5): 365-381.

15 Koprivica, M. et al. (2010): Estimation of Biomass in a Submontane Beech High Forest in Serbia. Acta Silv. Lign. Hung. , Vol. 6 : 161-170.

Kouta
by KoutaR
Mon Jan 28, 2013 3:12 pm
 
Jump to forum
Jump to topic

Re: New sites on giant eucalypts

The eucalypts in these areas can get so big for a number of reasons:
1. Long absence of fire (450-500 years between catastophic fire)
2. Deep, relatively fertile loam type soils
3. Reliable rainfall 1000 to 2000mm per annum
4. Very fast growth -E. regnans can get very large very quickly - also tall - 83m tall in 70 years - this tree puts almost no energy into protecting its heartwood - all energy is put into growth (E viminalis, E globulus, E obliqua also can grow very quickly)
5. Usually this competition occurs after a catastrophic fire where millions of seedlings all compete for light and space - only the fastest and strongest survive!

Diversity - In Victoria, where conditions suit it, regnans rules - only in in marginal areas will other species mix with it - E nitens in higher elevations, E cypellocarpa and E obliqua in lower sites, and E viminalis in riparian zones.
In Tasmania, there is often a little more mixing of eucalypt species, however, the best stands of regnans are pure stands - E globulus attains its best size and height when it is associated with regnans. Similarly some of the best E obliqua grows in mixed regnans/ delegatensis/ obliqua forest.

Hope this helps
Brett
by Brett Mifsud
Mon Feb 25, 2013 5:57 pm
 
Jump to forum
Jump to topic
cron