Thursday 9 October 2014

Template for LUDS presentation in Second-life

Hi

I have added more information to the first set of slides and completed half of  the assessmentt section 14h00 Friday 10 October

Download the template Power Point here -

Download the assessment for the Qarbon Campus Experimental Farm to understand the data included in the template Power Point above
Download map of assessment area

Your LUDS assessments for farmers, officers and researchers


Hi

Here are the LUDS reports that were sent to me yesterday and the spreadsheet of the developments/assessment areas

Download assessment area descriptions

Assessment area maps

Beaufort West.pdf
Bergrivier.pdf
Bitou.pdf
Breedevalley.pdf
George.pdf
Hessequa.pdf
Ikwezi.pdf
Kamiesberg.pdf
Kannaland.pdf
Knysna.pdf
Kou-Kamma.pdf
Kouga.pdf
Laingsburg.pdf
Nhlambe.pdf
Oudtshoorn.pdf
Prince Albert.pdf
richtersveld.pdf
SaldanhaBay.pdf
Stellenbosch-Drakenstein.pdf
Sundays River.pdf
Witzenberg.pdf

LUDS report pdfs sent in by students - I have replaced these with the report you submitted on 16 October for the World Food day event

Nhlambe's report was given to me on a memory stick

Wednesday 8 October 2014

EIA Assessment Practical 2

Hi

We are running out of time for me to show you how to extract data from the BGIS website. We will simply move on to concentrate on each of you finding your assessment area in your municipality from the description given in the spreadsheet below. The descriptions for both groups of ten students are included.

Download assessment area descriptions

We will then use the LUDS tool to extract the information you need into a pdf LUDS report and interpret the results.

I would still like you to work with your partner, the previously helped partner can now help their previously unhelped partner to find their assessment area. You can then help each other with the LUDS tool and interpreting the pdf LUDS report.

See you later
Martin

Tuesday 7 October 2014

EIA Assessment Practical 1

Hi

I will explain in class how you are going to proceed with your assessment of a development in your chosen municipality.

You will work in pairs and all will be revealed later including the developments you must assess.

Download the first group of developments for assessment

Thursday 2 October 2014

The products you should have after the municiaplities practicals

On completing these two practical should have the following products which you can now compare to the municipal biodiversity summaries which can be found in the LUDS section of the BGIS website.

For you municipality in all cases when calculating % area of your municipality use the area in the Sa municipalites Albers shape file provided in practical 2 

  1. A list of the protected areas with their area in Hectares and percentage of the municipality area in Hectares

    You obtained this by (also see the previous postings)

    Clipping the NBA 2011 formal protected areas shape file available on BGIS by the SA municipal boindaries shape file (provided for download in this blog) with your municipality selected and then dissolving it by oroitected area name.

    In order to get the areas you projected the file to the Albers Equal Area projection in QGIS and added an area and a percentage of municipality field called what ever you like in ArcView 3.2 see the posting below for the method.

  2.  A list of the vegetation types 2006  with their area in hectares and percentage of the municipality area in hectares

    You obtained this by (also see the previous postings)

    Clipping the National Vegetation Map 2006 shape file available on BGIS by the SA municipal boundaries shape file (provided for download in this blog) with your municipality selected and then dissolving it by oroitected area name.

    In order to get the areas you projected the file to the Albers Equal Area projection in QGIS and added an area column called "origarea" and a percentage of municipality called what ever you like in Arcview 3.2 see the posting below see posting below for the method.

  3.  A list of the vegetation types 2009  with their area in hectares and percentage of the municipality area in hectares by exactly the same method as above but using the 2009 SA Vegetation map update available on BGIS.

  4. And now for the tricky bit threat (conservation/ecosystem) status for the 2006 SA Vegetation type list for municipality

    You obtained this by

    Clipping the land cover shape file provided by the SA municipalities Alber shape file provided on the blog. Note the land cover is in Albers and it must therefore be clipped by the SA Mnicipaliies Albers shape. Now select gridcodes 1 and 5 which code for natural land cover.

    Clip the vegetation 2006 shape file projected into albers created  in 2 above by this clipped landcover shape file. This gives the remaining extent of the vegetation. Dissolve this new shape as the clipping will have added many polygons again. Remember to retain all the fields when dissolving it.

    Add a new area field called "remarea" and a remaining vegetaation percentage of municipality area field called what ever you like.

    Add another field for the percentage remaining for each vegetation type remarea/origarea*100

    Now check on the  BGIS website for the cut offs for threat status. A what percentage remaining is it classified as Critically Endangered, Endangered, Vulnerable  and Least Threatened and add a last field indicating the vegetation types threat status.

    Create a map of the vegetation types threat status using the correct colours for threat status as the legend. These may be found on BGIS.

You now have several summarized statistics which you can compare with those provided in the BGIS Biodiversity Summaries.

Try to understand whether the differences you see are due to real changes in the area of say the protected areas or due to a shift in the municipal boundaries.

  • For a start do this by comparing the provided you used in your calculation that you got from the SA municipalities Albers shape file NOTE Albers and the BGIS municipal area..
  • Compare the protected area sizes of your list to that on BGIS. Is there more land protected now, was this simply due to a shift in a boundary. 
  • Do the same for SA vegetation 2006 and 2009 comparing them to each other for changes in vegetation classification and for discrepancies by comparing the summaries 2206 vegetation types list to yours. Any discrepancies here should be due to a change in the boundary if your calculations were correct. Can you see where s is? Check by looking at the vegetation shape file in the downloadable  zipped biodiversity summaries shape files available for your municipality on BGIS .
  • Compare your list of threatened ecosystems and that of the biodiversity summaries on BGIS are they the same or similar. Remember the summaries list of threatened ecosystems/vegetation types was calculated nationally and then clipped for your municipality whereas  you calculated the threat status for your municipality's vegetation type  separately which will may lead to some interesting anomalies if a vegetation has been unevenly transformed across it distribution. For instance your municipality may have the last really large remaining piece which may lower its threat status when calculated for the municipality but raise it when calculated nationally.   

In power point use the lists with area you calculated for protected areas and vegetation types and the map of threat status to illustrate your more interesting findings of any of the anomalies or true increases/decreases you have found. 
 

Tuesday 30 September 2014

Municipality summaries practical 2

Hi

In today's practical you will continue with the GIS work you started last week. You will calculate the size (area) of the formal terrestrial protected areas and vegetation types 2006 and 2009 in the shape files you created last week.

You can calculated the forest patch, FEPA wetlands and river FEPA areas as well but you must complete the PA and vegetation types areas.

We will also calculate the threat (ecosystem or conservation) status for your municipality's vegetation types which means you will need land cover to clip out the remaining natural vegetation - remember the vegetation map you clipped to produce your municipality's vegetation types contains the original extents of the vegetation types in South Africa. Lesotho and Swaziland before the large scale land use changes of the modern era.

Download QGIS

Before we do anything more  download QGIS and install it - we will use this software for projecting the shape files. You can download the installation file for QGIS from a local server below. Install it on the machine you are working on. Do this first as it takes a while to install. Don't install any of the sample data to save time.

This is freeware so you are welcome to install it on your own computer. i will only explain how use QGIS for projecting your shape files today but you are welcome to do the entire practical using it. I will explain how to do most of the practical in ArcView 3.2 however.

Once it has started to install continue reading what you will be doing today.

Download QGIS

Projecting shape files to Albers Equal Area projection so that area can be calculated.  

The shape files you created last week are not projected they are in geographic- you cannot use these to calculate area, I will explain in class. We are going to use the Alber's Equal Area projection for South Africa for calculating area as it allows comparison across the country and is not too complicated. 

The zipped file below contains the SA municipalities shape in the correct Alber's projection.  


  • Unzip the SA municipalities albers and open it in QGIS by going to "Add vector layer" under the Layers tab 
  • Once it has opened right click on this layer in the layer list and set the project CRS from this layer. 
  • Now save a custom CRS by going to "Setting custom CRS"  under the Settings tab and add a new CRS by copying it as an existing CDS and give it a name so that you can reference it from now on when projecting your other shape files. 
  • In the Project Properties box under the Project tab enable "on the fly" projection under CRS menu item 
  • Open all the shape files you must project i.e. your municipality's protected areas, vegetation types and forest patches. 
  • Change these to the new projection by right clicking on each layer and choosing "save as". add the new shape file name and location and choose the new custom CRS you just created. Make sure it looks like this before saving. 

  +proj=aea +lat_1=-33 +lat_2=-24 +lat_0=0 +lon_0=25 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs

Go to the new shape file and open the .prj file QGIS created in Notepad and check that it looks like this   

PROJCS["Albers",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Albers"],PARAMETER["standard_parallel_1",-33],PARAMETER["standard_parallel_2",-24],PARAMETER["latitude_of_origin",0],PARAMETER["central_meridian",25],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["Meter",1]]

Well done! you can now safely calculate the area of your municipaliy's  vegetation types and protected areas. We will use ArcView 3.2 to do this. 

Adding areas to the municipality's vegetation types and protected areas shape files   

  • Add the projected vegetation types and  protected areas shape files as themes in ar4cView 3.2.
  • Open the attribute table of the shape file to which you want to add an area field/column
  • Choose "Start editing" under the Table tab
  • "Add a field" under the Edit tab, make sure the field is of type number with 2 decimal places and name it "origarea" for the original extents area of your vegetation type
  • Click on the new field column heading, then choose "Calculate" under the Field tab and enter the following
    [shape].ReturnArea/10000. This will populate the new column with the areas of that collection of polygons in hectares there are 10000 square metres in a hectare. 
  • Add a new field and use the field calculator to calculate the % area of you municipality which was originally covered by this vegetation type. This will look something like [orinarea]/<the are of your municipality*100. Note you MUST use the field called AreaAlbers I included in the SA municipalities albers shape file downloaded today. The area on the BGIS website for municipalities is out of date and the updated summaries are being poblished this year. Some municipalities have changed in size due to municipal boundary changes by the Demarcation Board since these summaries were published.

Calculating the area of the remaining  extents of the municipal vegetation types

You have to clip the vegetation types layer with a land cover layer which shows what is still natural and not transformed to other land uses e.g. forestry or agriculture.  We will use the national land cover 2009 rater grid available on BGIS. Download the raster grid, unzip it and open it in ArcView. Note you will have to enable the Spatial Analyst extension in order to be able to see this layer. 
open the attribute table and take note of which gridcodes are classed as natural.

In order to clip the vegetation by these two classes we must first vectorize the raster grid to a shape file. As this take a long time to compute I have done so for you.  


  • Add the land cover shape and the SA municipalities Albers to an Arcview. Both of these are in the Alber's projection and should be visible when opened together along which your other projected files you have made.. 
  • First clip the land cover shape by your municipal boundary as you did last week by selecting your municipality and clipping the land cover to a new shape file of your municipality's land cover. 
  • Select the "natural" gridcodes in your municipality's land cover by using the query tool 
  • Now clip to a new shape file of your municipality vegetation types in Albers which contains the original extents area calculations by the selected gridcodes of the municipality's landcover. The result is is the remaining extents of the vegetation types of your municipality.
  • You will need to dissolve the remaining extent vegetation types shape file on Bookcode as the clipping will have added numerous separate new polygons.   
  • You can now add a field called "remarea" to its attribute table and calculate the area of the remaining extents
  • Calculate the percentage of the original extent of the vegetation type which is still remaining. [remarea]/[origarea]*100     
  • Use the BGIS website to find out the cut off points for classifying a vegetation type as Vulnerable, Endangered and Critically endangered. Add a field called ThreatStatus and classify each vegetation type as Least Threatened, Vulnerable, Endangered and Critically Endangered.
  • Make a map showing your municipality's vegetation types threat status with the correct colours used in the legend. Check on BGIS to see what these colours are.