By Nick Walker

April 14th, 2016

Introduction Spring 2015: EVPP 505 Fundamentals of

Environmental GIS.

Applications for:

1) My own dissertation research.

2) Jobs in the government.

3) Jobs in the private sector.

My research

My dissertation is on the American eel (Anguilla rostrata), a species that has declined to less than 1% of historic levels.

Where have American eels been found in the Chesapeake Bay region?

How have their numbers changed with time?

What factors might affect their presence/absence and abundance?

Data sources Biggest challenge – not a lot of data on these fish.

These data are generally not publicly available.

They will want to know how you plan on using their data, and may have restrictions on what you can do with it.

Combining data

Data from different sources is not always consistent.

Things like dates and geographical coordinates have to be organized before it can be used.

American eel survey sites (blue circles) along Virginia tributaries of the Chesapeake Bay. Red circles indicate hydroelectric dams. Highlighted rivers indicate sections where riparian buffer data is available.

Select By Attributes – VA Rivers

Buffer rivers

Clip rivers with riparian buffers

Show values of riparian buffers

Riparian buffers

National Park Service

Run-off carries pollutants to the Chesapeake Bay, so Best Management Practices (BMPs) have been established to reduce pollution.

How well do the National Parks meet the standards for total maximum daily loads (TMDLs) set by the EPA?

We added a basemap, then outlined the parks.

This way we could draw polygons over the areas with forest cover and impervious surfaces.

The USGS small scale data set was used to add roads and other features to the base map.

We wanted to find out which hydrologic unit codes (HUCs) best corresponded to each geographic data point from the parks.

A list of HUCs is available from the USGS National Hydrology data set.

These data were added to the base map and joined using the “Union” command, with each HUC12 shapefile added as input features to the output class “HUC12”, with JoinAttributes “ALL” and no XY tolerance.

BMP data were added from this spreadsheet.

This tab is the stormwater template, with a separate tab for the agricultural template.

To align the HUC12 feature class with the BMP point data, the Spatial Join command was used, with the point data as the target layer, the HUC12 data as the point layer, a one-to-one join and only the relevant target features kept.

BMPs were drawn as a polygon feature class.

Metadata

Finally, metadata was added in FGDC format and exported to an XML file.

NPS – BayFast The ArcGIS data was then used in a program called

BayFast, which calculates how well the parks are meeting the BMP goals.

Park Boundaries drawn in BayFast, based on ArcGISdata. Best management practices can be applied across various land use scenarios.

Landscaping – Park Fairfax

Could we do better than blueprints from 1943?

City of Alexandria GIS Data.

What I’ve learned1) This work has brought me into contact with people

from different fields:

Biologists/Ecologists at universities.

Federal agencies (USGS, NPS, DOI, USFWS).

State agencies (FWS, DNR, DGIF).

Private sector (e.g. landscape architects).

With ArcGIS I have the opportunity to work in fields I might not have considered otherwise.

What I’ve learned.2) I am constantly learning new things.

Clients/employers have a way of asking for things I’ve never even considered.

Get used to Googling for help. Things are not going to work smoothly the first time around.

“Can you rotate the map so the buildings look square?”

“Can you overlay point data with polygons and export the results to an Excel table?”

“Can you create new layers to draw objects on the map?”

What I’ve learned3) Knowing other software programs is a big help.

Adobe Photoshop is like duct tape, it can fix just about anything.

Ex: I got a phone call at 11 pm with a request to resize 286 images from a scale of 1”=10 ft to 1”=20 ft within 36 hours.

Excel macros (Visual Basic) are also helpful for some tasks, e.g. converting degrees to decimals to get location data in a consistent format.

Sub ConvertDegree()Dim Rng As RangeDim WorkRng As RangeOn Error Resume NextxTitleId = "KutoolsforExcel"Set WorkRng = Application.SelectionSet WorkRng = Application.InputBox("Range", xTitleId, WorkRng.Address, Type:=8)For Each Rng In WorkRng

num1 = Rng.Valuenum2 = (num1 - Int(num1)) * 60num3 = Format((num2 - Int(num2)) * 60, "00")Rng.Value = Int(num1) & "°" & Int(num2) & "'" & Int(num3) & "''"

NextEnd Sub

Source:http://www.extendoffice.com/documents/excel/1497-excel-convert-decimal-degrees-to-degrees-minutes-seconds.html

What I’ve learned4) Write down all of your steps.

If you come back months later to change something, are you going to remember everything you did?

You will also need to show your methodology to publish your work.

5) Keep your ArcGIS licenses up to date!!! While preparing this presentation, I discovered one of

my laptops had an expired copy of ArcGIS.

The evaluation copies only last one year and this is not something you want to discover if you are working on a deadline.

What I’ve learned5) People skills are just as important as technical skills, if

not more so.

Need to be able to communicate with people in different fields and show why your work is relevant.

Example: landscape architect had never used any form of GIS, I had never done landscape design work, so it often took several conversations for us to understand one another.

Acquiring data – people are not always motivated to share datasets with you.

Interdisciplinary research requires collaboration.

Thank you for listening!Questions?