Questions tagged [species]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
3
votes
1answer
208 views

From areas of several species ranges (polygons) to a map (raster) expressing the count of overlapping polygons

I am not able to resolve the problem that follows. I have some separate shapefiles files, each one representing a given species range. Some layers have multiple polygons. I would prefer to solve this ...
2
votes
1answer
476 views

Is there a way to create a presence/absence matrix of polygons per cell in a grid using qGIS?

I'm working in QGIS with species distribution polygons and I want to know how many cells in a grid does the polygon overlap. I've tried creating random points within the polygon and then used vector&...
2
votes
0answers
222 views

Risk and vulnerability analysis for the spread of alien species [closed]

Based on knowledge about the potential for proliferation of alien forests species we are looking at possibilities for modelling the process. Inputs should be area for initial plants, wind, elevation, ...
1
vote
2answers
30 views

SDM: Dealing with coarse environmental data

I wish to determine the most important environmental covariates controlling a species distribution. I have a large collection of species presence data for a small survey area (e.g., 600 presence ...
1
vote
1answer
133 views

Extracting raster values from polygon perimeters using ArcGIS Spatial Analyst?

I am currently working on a project to identify local ponds or water bodies that have high probability of species occurrence. I'm using BioClim climate data, SSURGO soil data, and a DEM layer for a ...
1
vote
1answer
403 views

Designing interactive map of botanical garden in QGIS?

Using QGIS is absolutely new to me but I hope, we can make it as short and easy as possible to put my idea into practice. I hope that QGIS is the appropriate program for this purpose. I have COREL-...
1
vote
1answer
161 views

Kriging predictions for presence only data with Maxent

I was doing some geostatistical analysis (variogram+kriging) for a "presence only" type data in a species distribution modeling context. Since, we know that when estimating the (empirical) variogram, ...
1
vote
1answer
42 views

Counting unique species in polygon layer and buffer

Within QGIS I'm working on a data set that contains species at 100m resolution (eg OSGB 6 fig) and 10m or finer resolution (eg OSGB 8 or 10fig). The objective is to count the number of unique species ...
1
vote
0answers
95 views

Maxent Probabilities Values

I am working on my first experiment with Maxent. I am using two different species. When I receive the output map and look at it in QGIS the values for suitable habitat probability do not sum to 1. ...
0
votes
2answers
143 views

Species ranges into fishnet grids

I need to create a fishnet grid (presence and absences) form species distribution areas (polygon shapes). But I need to define that presence (value 1) is correct when more than 30% of the grid is ...