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Messages - Loch

Using SLAMM / Time step restriction
August 03, 2010, 06:05:17 PM
Hi Jonathan,

I've developed a SLAM model for a sub-tropical wetland system, and would now like to link this to a population model. I have one issue in that I'd like to have flexibility re: time steps. Is the SLAM model restricted to one year time steps only? If I have the flexibility to have 3 or 6 month time steps, that will be good. Thanks.

Using SLAMM / Re: NWI
April 25, 2010, 10:41:37 PM
Hi Jonathan. Thanks for your last reply.

We've thought carefully about our crosswalk situation and we've managed to transfer most of our wetland types across to ecologically similar (NWI) wetlands. We have one further issue. Some of the tropical Australian wetland communities don't respond to inundation according to the (decision tree) criteria used in SLAMM (Table 3, page 31 Technical documentation). We need to change some of these, otherwise our model will not be relevant. So for example, we require scrub-shrub to change to a community other than salt marsh.
Can we do this without altering the source code? If not, will minor modifications to source code have unforeseen consequences?

Using SLAMM / Re: NWI (decision tree)
April 14, 2010, 03:42:35 AM
Hi Jonathan. Sorry, one more important matter:
In tropical Australia, we have a coastal wetland classification that differs to the US NWI, not only by species type, but also by (species-specific) response to inundation and erosion. We go through the process now of cross-walking our wetland community data, but our communities may not necessarily convert to say open water or tidal flat. One possible option may be for us to alter the (global) source code, so that we derive a new decision tree based on Australian wetland types, with specific response to inundation, accretion and erosion. What are your thoughts on this?
Using SLAMM / Re: NWI
April 12, 2010, 01:10:55 AM
Hi Jonathan,

Re: land-cover categories and the decison tree - are there a minimum number of categories that can be used for a model? Our wetland data comprise just 11 categories and while we may be able to subcategorise some of these, the data just aren't as specific as the US NWI.

Using SLAMM / Re: NWI
March 17, 2010, 05:49:37 PM
Using SLAMM / NAVD88
March 16, 2010, 11:17:38 PM
Hi Jonathan,

You don't happen to know what the vertical control datum (VCD) is for Australia, or the Asia-Pacific region? If I use LiDAR data for the Australian region, then will these have a pre-specified VCD?

Using SLAMM / Re: NWI
March 14, 2010, 11:18:30 PM
Thanks Jonathan, we'll re-categorise our wetland classes according to the SLAMM6_nwi_codes. Can we change these codes within the xls - what do you mean by 'crosswalk'? I note that it is read-only.

Also, thanks for answering the query on rows + cols, I got that sorted.

March 03, 2010, 10:33:44 PM
G'day. I'm using SLAMM6 for SLR in Queensland Australia. I have a query on (the required SLAMM category) NWI: these don't exist for the region I work with (Non US).
Also, if I was to source aerial imagery for the region, do the Nrows and Ncolumns have to match? The pixel size won't be the same.