Hot answers tagged land-cover
9
You can use GRASS GIS for this which supports texture extraction and image classification based on a radiometric/segmentation approach. For an idea, check this conference abstract, a planned talk at the Geoinformatics FCE CTU 2011.
See also: http://grass.osgeo.org/wiki/Image_processing and http://grass.osgeo.org/wiki/Image_classification for an overview.
7
I poked around on the State of Hawaii GIS site but most of the layers were too general or too old.
The NOAA Coastal Services Center has some Landsat ETM derived land-cover data for Hawaii. There's also some 2.4m Quickbird-derived land-cover data for all islands except the Big Island.
Hope that helps!
5
Split tools has an error in ArcGIS 10 SP2. The tool makes the split, but leaves all features empty. Esri was registered this error and recommends for now, if you want use the split tool, downgrade ArcGIS to SP1. I suggest you visit this link http://resources.arcgis.com/es/gallery/file/geoprocessing/details?entryID=6C5D9A77-1422-2418-7F6C-01564409B1AF , where ...
4
It does vary by Country - Turkey is poor because the data they used is minimal.
For France, Germany, UK, Ireland the data accuracy is vastly better.
If you want the accepted paper on the project
"The Corine Land Cover (CLC2000) database received a thumbs up for accuracy from an assessment of the project, details of which were released by the EEA today.
...
4
To generalize, try running a majority filter. This is available in saga (and grass as well, check markusN his answer).
An explanation for how it works from arcgis:
http://edndoc.esri.com/arcobjects/9.2/net/shared/geoprocessing/spatial_analyst_tools/majority_filter.htm
3
You can first use the "mode" operator of r.neighbors in GRASS GIS (via Sextante plugin), then vectorize with r.to.vect to obtain polygons.
Perhaps the "mode" operator should be run more than one time.
3
you can use gdal_polygonize.py for converting raster to vector, if u previously use .
some information is here.
produces a polygon feature layer from a raster
SYNOPSIS
gdal_polygonize.py [-o name=value] [-nomask] [-mask filename]
raster_file [-b band]
[-q] [-f ogr_format] out_file [layer] [fieldname]
beside this in qgis ...
3
Try converting the shapefile to a file or personal geodatabase, then perform the split and save the results to a geodatabase.
In my experience with ArcGIS and vector analysis, shapefiles can be buggy about large feature sets with numerous nodes/vertices and shared edges (e.g. many landuse datasets).
3
If I understand you correctly, you are looking for a supervised classification procedure. Some theoretical background: http://rst.gsfc.nasa.gov/Sect1/Sect1_17.html
This is certainly possible through grass:
http://grass.osgeo.org/wiki/Image_classification#Supervised_classification_2
As an alternative you could also look at saga (I'm not saying it is better, ...
3
Creating landuse database, you need sensor technologies to detect and classify objects. i think you already know that:
There are two main types of remote sensing: passive remote sensing and
active remote sensing. Passive sensors detect natural radiation that
is emitted or reflected by the object or surrounding areas. Reflected
sunlight is the most ...
3
Slight correction to a previous answer...
NOAA's Coastal Services Center now has 2.4 meter land cover data for all eight of the main islands of Hawaii. Here is the link to the Coastal Change Analysis Program (CCAP) high-resolution land cover download page:
http://www.csc.noaa.gov/digitalcoast/data/ccaphighres/download.html
Select from the drop down menu ...
2
We've got some NLCD 2001 data from the USGS on WeoGeo.
http://market.weogeo.com/datasets/open_nlcd_2001_hawaii_land_co.html
If you look at all the land cover data we have for Hawaii, you may see something you need:
http://market.weogeo.com/?query=Land%20cover&lat=20.46&lon=-157.505&zoom=7&layers=BT
We've got hundreds of mostly free land ...
2
LUCAS
This data is available in Vector and Raster Format here:
http://www.eea.europa.eu/themes/landuse/interactive/clc-download
This data was included in the Open Street Map Project:
http://wiki.openstreetmap.org/wiki/WikiProject_Corine_Land_Cover
more detail
http://wiki.openstreetmap.org/wiki/Corine_Land_Cover
RAMON is another that is Combined ...
2
NOTES
(these notes are subsidies, not a "complete answer", I need YOUR answer!).
I have something, but no reliable sources/references, neither bether clues or confirmations... Do you have sources?
Geometrical principles:
Points with POSTCODE defined: there are two ways to define georrefered points of POSTCODES,
1.1. by postal address: addresses ...
2
As Aragon correctly points out, there are many options for detecting changes in land use using GIS.
Before starting, it's worth being aware of the differences between land USE and land COVER, see here for a helpful explanation (it's certainly a distinction that you'll want to make in your dissertation). In addition, bare in mind that any data that you ...
2
there are lots of method for calculating land use change in gis systems. if you want to use Arcgis, you should check out Confusion Matrix Analysis for your work. with confusion matrix you can also measure urban sprawl, too.. it is of course necessary to do some research.
Wikipedia defination:
In the field of artificial intelligence, a confusion matrix ...
1
Look into Group Stats plugin. I've described it's usage in http://anitagraser.com/2013/02/02/group-stats-tutorial/.
You can put the land use class in rows, the "sum" operator in columns and "area" in value to calculate the sum of all areas per land use class.
1
You could use the FocalStatistics tool in the raster calculator.
Something like:
Con("landcov" == 3, FocalStatistics(SetNull(("landcov"==2)|("landcov"==3),"landcov"), NbrRectangle(5,5), "MAJORITY"), "landcov")
What this does is for cells that have the landcover class you want to replace (Con("landcov" == 3...), replace that value with the most frequently ...
1
I did succeed in finding this:
http://www.vgt.vito.be/
...but I have no idea how to use the data therein. Examining the pixels of a given HDF gives me a bunch of integers without clearly defined semantics.
Look at this:
http://glcf.umiacs.umd.edu/data/treecover/
While it's from 2000, I can at least tell what the numbers mean; see heading "Code Values".
...
1
(Don't think there is a one source solution for this question)
Natural England has a huge source of Land Use across England.
Land Use Categories:
Areas of Outstanding Natural Beauty (England)
Biosphere Reserves (England)
Limestone Pavement Orders (England)
Local Nature Reserves (England)
Marine Conservation Zones (England)
National Nature Reserves ...
1
Depending on what distinction you make between land cover and land use, the Land Cover Map 2007 may be of interest to you. Released in 2011 it is, as far as I'm aware, the most up to date land cover dataset for the UK as a whole. There are several different versions: a 1km raster, a 25m raster and a vector dataset. The 1km raster uses a simplified ten-fold ...
1
I ended up manually digitizing here to correct the issues as I was unable to go back and reclassify the landcover. At the time I posted this question, I was fairly unfamiliar with the raster operations mentioned by @whuber, but since then I have learned much more about those operations and I suspect they would do the job quite nicely.
I will have to try ...
1
could you calculate some stats for each of the polygons and then remove all those over a certain length, width or area?? just thinking that if you know that the polygons you want to remove are long and thin and you can find some measurements that represent this then you could identify and remove the ones you don't want.
1
There are several global land cover products. Globcover, from ESA, is the one (I think) with the best resolution - 300m. It has a fairly detailed nomenclature based on FAO's classification system.
Also, if your AOI is in Europe, you can get CORINE Land Cover - a Land Use/Land Cover vector Map for Europe with 25ha of Minimum Mapping Unit and 44 classes of ...
1
If your study area is within the conterminous United States, you might be interested in the National Land Cover Database (NLCD); the latest data is from 2006, and is at a 30-meter resolution.
1
You would be able to do that with GRASS.
You will first work with raster data :
I will point you out to that tutorial. See the raster part.
You will use r.mapcalc and r.reclass to extract desired features.
r.to.vect will permit you to vectorize your data.
Finally you will manipulate vector data. v.db.select and v.class will help you.
Only top voted, non community-wiki answers of a minimum length are eligible
