To do so, we will follow the next simple steps.

First, we select the layer(s) that we want to export. We choose the select option to select.

Once selected, Right Click the layer and click Export to CAD. Select all layers that we want to export and specify where.

Go to the folder where we have placed them and drag it to AutoCAD.

Taking a look at the attributes table we can observe that the attributes are kept.

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To do so, we need to first have a geodatabase. To create it, right click the folder where we want to locate it inside Catalog and select new > file geodatabase. This is a container where we can save the folders.

We also need to generate a file inside the geodatabase called “Feature Dataset”.

Right Click the geodatabase, New > Feature Dataset. Here you will be asked to indicate the projection of the layers that will be inside it.

We now have to import the layer(s) that we want to analyse. To do this, right click Import (I recommend the “multiple” option even though we just want to introduce one layer as it is less arduous).

Once imported, add the layer inside feature dataset.

With the layer inside it, right click Feature Dataset > New > Topology.

Name the topology and specify the tolerance distance (generally it is 0,001 unless you are looking for something specific). The next window will ask to select the layer and assign a range of importance to the layer (if you want it to be the same, give it the same number).

“Add rule” is to add mnemonic rules that will be followed.

On the right hand side you will see a description and the drawing explaining the meaning of each rule. Once done, click finish.

When finished, the topology image will be added inside feature class and we have to right click it to validate it.

To validate and analyse the errors that may exist, we, first of all, have to activate the topology tool.

Next, we have to load the file created in the table of contents. It will ask us if we want to add layers that belong to the topology, we will say yes so that the errors on the map are loaded.

Following, the editing will start (same as editing any layer, right click on it, select edit and modify it using the editor tool) taking a look at the pointed errors.

Something to take into account is that, although you correct the error, the layer of errors (red) is there, and it won’t change until we review the errors. The reason for this is that the red vector layer is a copy of the previous one but with the error re-marked.

If the “Topology” control table is not open, you will have to open it via customize.

In the “error inspector” table we can observe each individual error as if it was an attribute table allowing us to work with them. This opens clicking the “error inspector” button of the topology tool.

If there is some point that we want to omit as an error, we just have to right click on it and select “Mark as exception“.

With the bar above, we can choose to only display the errors created under a certain rule.

Once we have solved the error, we select the “seach now” button of the “error inspector”. This way we save the editing of the layers until having corrected all errors.

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ArcGIS groups it in two categories:

Geometric Networks: The agent cannot choose the direction of travel as it depends on external forces like gravity or pressure (as in the case of water lines).

Network Dataset: The agent is free to choose the direction of travel (such as a vehicle).

• Creating a network dataset:

To be able to solve questions using ArcGIS such as closest facility, shortest route, optimum location, etc. we first need to create a network dataset.

We need to generate a geodatabase and a feature dataset to organise it: New > File Geodatabase

Then we add the layer inside by: Right Click > Import > Feature Class.

Right click on the feature imported and select “Network Dataset“.

And now we start to set the Network Dataset parameters.

We first need to give it a name and then select the layers that will have an influence, for this case it will only be our polylines layer.

The next window refers to the option of adding forbidden turns.

To add them, we would need to have a generated layer representing them. As we don’t have it, we select “No”.

The next window is to decide where we want to include the Nodes (connecting junctions).

We define the connectivity of the network.

We will choose if the connecting junction appears at the beginning and end of each line or on any vertex.

We select “Any vertex”, to increase the mobility of the network.

The following window refers to the elevation.

The option using Z-coordinate values from geometry means that if two lines share the same X,Y point, they will be connected but if it turns out that it is a bridge, they will not.

For this case we select the second option and we choose the attribute that defines the start and end of this line-bridge. As in our case it is a plain network, we choose the option “None”.

Next comes the most important part as we will add the attributes to generate the network.

To add other attributes we select “Add ” so that we can choose the values.

For example: Descriptor means that the value does not depend on the length of the element (as for example speed).

Hierarchy is the order of preferences (preference given to the fastest roads in our case). We would have created an attributes field that depending on the type of route it will be under a hierarchy of 0 to 3 where 3 is the value with more preference.

If some field doesn’t exist, an exclamation sign will appear next to it. Clicking it, we are able to create it.

For our case, we will generate the time to travel each route (as each speed is the maximum).

We say that the type is field, we click the operations table and select the operation as time is length/ speed.

You will have to do this in both exclamations unless it is different for each travel direction.

Once accepted we convert the units to seconds.

In the next window select if we want to obtain driving directions. We will say yes and also choose the option to obtain the name of the route.

Clicking Next, we will see a summary of all the settings and we select Accept to generate the dataset.

The dataset is now generated and we are ready to work with it.

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This is one of the most common tricks to make a map look nicer.

Once the Project is finished, if it is represented in an orthophoto or raster layer like this one:

We can follow the next tip, which consists in adding a more realistic tone to the image using relief.

To do so, we will use the original raster file.

Using tools as the ones seen in previous posts, we will try to create a shading to add relief.

We now add the orthophoto / raster on top, and add 40% transparency through the next steps:

Go to properties, right click the layer and select display.

The result will look like this:

These are small tricks that can make your presentation stand out as a high quality presentation.

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Go to: ArcToolbox Spatial Analyst Tools > Distance > Euclidean Distance

When working with raster data, the most recommended is to have the parameters pre-stablished or, if not, specify the maximum distance.

It works with lines as well as with polygons.

   Layers

Polygons

We can modify the distance between the different colours, as well as the quantity of colours and the shape type, as we do in a vector layer.

To do so, we right click the layer and select Symbology. In the dialog box, we will go to symbology where we will choose the quantity of colours or classes that we want to establish, and if we want to manually specify the distance that each colour is going to represent, we click the tab “Classify”.

For this example, we will end with the following figure:

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The first step is to find the terrain location of the study. There are two ways to find it:

• downloading it as an ortophoto from a web resource such as a National Geographic Institute (this requires to first locate the quadrant of the study area and then download it)
• through the basemaps application inside ArcGIS (if you choose this option the computer will work slower due to the fact that it will have to move a huge amount of data). To do so we will:

Access the File Menu > Add Data > Add basemap

Select the option that allows us to see the image with increased realism, “Imagery with labels” (I select this option instead of “Imagery” to guide us better with the annotations).

If we know the location coordinates we can locate the area more easily clicking in the search tool.

If not, we do it manually.

The next step is the design of a new polygons layer. Regarding this, it is very important to know where this layer is projected as if not the units used for the calculations will be undefined.

We will project going to “Edit”.

Once the layer is created, before editing, we will access the Attributes Table right clicking the layer and will add a new field, indicating that it is double (so that it admits decimals).

In this moment is when we click “Edit” and generate the polygons of the area that we want to calculate.

The next image will appear (if not we search for it in customize) and we select the specified task:

We will take a look at the right side of the screen and following this order we select these icons, and following, we start to draw the figure.

Once this is done, we will end the editing and access again the attributes table, selecting the new field generated and click Calculate Geometry > Calculate Area / Perimeter.

We can vary the units under the “Units” section.

If we want to keep both the data and the polygons we have to click “stop editing” and save.

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Let’s start with this main shape, a series of contour lines extracted from a raster. They represent at which height stands each one and this is how we will study the existing volume of a mountain.

First, let’s create the raster shape.

Use the “Topo to raster” tool, located in: 3D Analyst Tools > Raster Interpolation> Topo to Raster

We have to realize that in the option “field” it will be selected the field that refers to height, in this case the “contour” field.

The cell size and extent field are selected form the DTM where we have obtained the contour lines.

We will obtain something similar to this:

We now need to delineate the calculation area.

We will extract by mask and for that we need to have a mask that will be the mountain´s base.

We will select the base line through the specified tool and choose “extract” right clicking the layer.

As this is a line, we need to convert it to polygon: Data Management Tools > Features > Feature to Polygon

Therefore we have the base polygon and we will extract by mask using it as the mask: Spatial Analyst Tools > Extraction > Extract by Mask

Before calculating the volume, we need to know if we will decide the option “Above” or “Below” and also have the Environment settings prepared regarding the coordinates and raster analysis.

As in this case we want to calculate the volume inside a mountain, we will select the option “Above”. If the volume would be the one of a lake, the option should be “Below”.

3D Analyst Tools > Functional surface > Surface Volume

We have to open the generated file in .txt format in the folder where it has been saved.

This document indicates that the 2D area is 23125 m², the 3D area is 23450 m² and the volume is 196067m³.

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At first sight it is hard to appreciate the details of the image not knowing which part falls inside the map.

In order to make its esthetical look seem better, we will apply a hillshade effect to the DTM.

This is a useful tool to turn the map more pretty and be able observe it in more detail.

Follow: Spatial Analyst Tools> Surface> Hillshade

In the dialog box, we will only select the raster and the file where we want to locate the output raster. All other values will remain the same.

The resulting map will be like the following one:

We insist that this is only an esthetical image and it helps us learn where we are located, as the value of each pixel changes.

As seen, the highest DTM value is 798 while the hillshade value is 254.

Enjoy!

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We will follow these 3 steps:

1.  Analyse the slopes of the terrain
2.  Analyse the proximity to rivers
3. Carry out the multicriteria analysis

1. Analyse the slopes of the terrain

We need a DTM raster layer.

First of all we are going to use the Slope tool: Spatial Analyst Tools > Surface > Slope.

Now, the problem is that we have data in a different scale.

Therefore we will reclassify it in 4 degrees according to its gradient, being the highest number the one of biggest inclination: Spatial Analyst Tools > Reclass > Reclassify.

First, click Classify in order to fix the classes and define the break values.

Click OK and you return to the previous window where we will value the areas with highest inclination with a bigger number.

2. Analyse the proximity to rivers

We need to obtain the river basins. To do so, lets go to: Spatial Analyst Tools > Hidrology > Flow accumulation.

Next, with the generated raster we select:

TRICK: Going back to classify inside reclassify, we can observe the graphic and find the accumulation value of the river. We will use the raster calculator to determine that it select those values bigger than the accumulation value.

Spatial Analyst Tools > Hydrology > Stream to Order.

In the first window we choose the raster that we just generated and in the second one the resulting “flow direction”.

We transform this to polyline, do a 300m buffer and return to raster:

Add the line layer that we just obtained, select 300m (to obtain the area surrounding 300m of the whole polyline) and select Dissolve all.

We will finally generate a raster.

3. Carry out the multicriteria analysis.

We will now reclassify the buffer raster in such a way that it has value 4 (as the whole raster will have value 0, we will give it a high value for the future sum).

With the raster calculator we sum the reclassified slope and the reclassified buffer.

The areas of value 8 are the most dangerous ones. The risk will decrease as you move down the scale value.

Overlaying the raster to the shaded DTM we can observe in detail the most susceptible risk areas.

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We need a point layer representing the presence of the species, correctly projected, and a map of the area that will be used as a guide.

Our goal is to determine the presence of a bird (seen or heard) through all Donana’s national park (Spain). (The data used is not real).

We will follow these 3 steps

• To generate a fishnet:

Data management tools > Feature class > Create Fishnet

In the dialog box, select the new layer, where we want to save it and how we want to name it.

We can also specify the extension of the area. In this case we will choose the same area extent as the National Park.

In the following options we can decide how many cells the grid will have depending on the cell size (width and height) or, if this information is missing, on the number of rows and columns. You can also choose both options.

There is the option to select label points, this is, another point layer where each point appears in the middle of each grid cell. If not interested, unclick the box.

Finally we have to decide the geometry of the new layer, that can be polygon, as in this case, or polyline.

We will create a 25×25 grid net that extends throughout the whole area of the national park.

• Next we have to do a join of the net with the point layer.

Right Click the generated net – layer and choose Joins and relates > Join.

Select “Join data from another layer based on spatial location” and choose the layer to join to this layer.

Tick the first option and the option “sum”. Write down the name for this new layer.

• To modify the symbology of the layer:

Right click on this new layer to select Properties > Symbology.

Indicate Categories > Unique Values and specify the field that will change its symbology.

In the case of the Join this field will be “Count”. Choose “add all values”.

We will preferably decide any type of graduated color symbology as it is visually more outstanding.

The result will be something similar to this:

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