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A range of rapidly developing technologies can be used to effectively
design, gather, analyse and present biological survey data. An obvious
example is geospatial technology.
Geospatial technology has three main components: geographical information
systems, remote sensing and global positioning systems. These may
be briefly described as follows (see links at the end of this module
for more comprehensive explanations):
- A geographic information system (GIS) is a digital database
that contains a representation of the real world derived from
survey in the field, often using GPS. Through GIS and remote sensing,
together with a set of tools or functions for the retrieval, manipulation,
and analysis of that data, this database is ultimately transformed
into useful information for management purposes.
- Environmental remote sensing is the observation from
a distance of areas on the ground using electronic devices that
commonly measure electromagnetic properties (in the visible, infrared,
and microwave bands of the electromagnetic spectrum) of objects
on or near the ground.
- Global positioning systems (GPS) are satellite-based
systems that provide locational data on or near the surface of
the earth for users with a GPS receiver.
Use of the technology
In the environmental context these three related technologies
are usually integrated. GIS provides a repository for remotely-sensed
and GPS data and a set of tools to manipulate that data. Remote
sensing provides synoptic data at periodic intervals. A GIS is used
to facilitate the processing of these images. GPS provides an invaluable
tool for ground-truthing GIS and remotely sensed data in the field.
In a relatively short space of time this technology has become
virtually indispensable for environmental survey and fieldwork.
The application of this technology enables scientists to survey
larger areas more effectively and to undertake data-intensive processing
and analysis tasks that are simply not practical using traditional
approaches.
Significance of this technology?
Spatial technology is an enabling technology that is extremely
useful to environmental scientists and managers because it brings
together a range of database, mathematical, statistical, and modelling
tools for handling spatial data in an accessible way.
There are ways of calculating location and area, other than using
a GIS (e.g. manual techniques such as transparent grids for calculating
area and map wheels for calculating perimeter on air photos and
maps), most of these techniques are far less cost-effective and
efficient than using spatial technology. These technologies still
require the visualisation and decision-making skills of a qualified
operator, and provide a powerful system for storing, retrieving
and displaying data and information.
Application to Flora and Fauna Survey
Spatial technology has potential for use before, during and
after flora and fauna surveys to maximise the benefits and minimise
the cost of survey work. Survey work is commonly part of an iterative
process whereby data are collected and analysed, results are synthesised
and passed on to management for decision and subsequent action.
The process is then repeated to evaluate the results of those decisions
and actions, refine the predictive model on which they are based,
and repeat the process. In a scenario like this, a geographical
information system and the related remote sensing and GPS technologies
provide important tools that can streamline this process and perhaps
even automate aspects of the monitoring process.
It is important to have a clear idea about how data is handled
within the system. This will ensure that the data collected during
a survey can be seamlessly and efficiently integrated and used.
Typical components involving spatial data handling are outlined
in the case study.
It is worth noting the interdependencies between these components.
For example, the approach to classification will strongly influence
how the data are analysed, and therefore the results and extrapolations
made to sites not studied. This has the potential to determine the
usefulness of the work for managers. It may also influence the data
you choose to collect, the sampling strategy you employ, and the
instruments you use to collect the data.
A case study
We will now look at a GIS case study that takes you on a guided
tour of a typical environmental management information system. The
study will focus on the flow of data through the information system
as it relates to spatial technology for use in flora and fauna survey.
Each component in the information system is briefly reviewed and
where appropriate illustrated with a map and associated attribute
data from a GIS. The components are presented in the sequence that
they might be expected to occur in such an information system. They
can be grouped into before, during and after, survey categories.
A review of the components reveals just how important the survey
work is to the information system as a whole, and underlines the
significance of making sure that the data collected are relevant
and appropriate to the requirements of the system. This is done
by thorough preparation and planning of not only the fieldwork itself
but also the integration of the data into the system and their subsequent
analysis.
Now work through the GIS
case study.
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