A Web Based System for Calculating Carrying Capacity

of Herbivores

CS 470

Oran Weaver05/18/05

System Overview

• Two clients– UAA’s Department of Biology – Don Spalinger– U.S.D.A., Forest Services, Pacific Northwest

Research Station – Tom Hanley

• Purpose– Provide a global access point for:

• Calculating carrying capacity of deer for a hectare of land with a set of nutritional constraints using Tom Hanley’s method

• A user interface of a known set of nutritional data

Data Sources

• Computer Models– Open source FORTRAN program developed

by Tom Hanley and James Rogers• Data entry by text file• No longer used

– Excel spreadsheet using a linear solve function with VBA

• Current way of calculating carrying capacity• Data entry by hand• Static number of input/result fields

Data Format

• Animal constraints:– Energy/protein requirements

• Plant data– Energy/protein elements

• Based on the available energy and protein in the food supply, how long would a deer stay in an area

• A region is an area of land divided into stands• Stands are a manageable area of study

Results in Excel•Very large and static in nature

Final Product

• Dynamic Structure

•ASP.NET

•C#

How was this created?

• System Design– Session data stored for each user

• Keeps track of calculator data without interfering with other users

• Handles secured area for data management

– Data Tables • Like an array, formatted as a table similar to an Access or

SQL Server view• Allows for easy manipulation of data without affecting the

actual data base

– Lp_solve• Non-commercial linear programming code • Programmed by Michel Berkelaar

Web Layout

Import

plant data

Log in

Entry point for Web users

Enter constraints and Title

Search for plants and log into secured area

Change password

Manage Plant Data

Manage Stand data

Manage Accounts

Enter Animalconstraints

Enter Plant Data

View Results

Lp_solve

Data Base DesignPlantPlant_key*Plant_namePlant_type(fk)Plant_class(fk)

ClassClass_name*Class_major(fk)

MajorMajor_type*

TypeType_name*

BiomassBiomass_key*Biomass_valueBiomass_plant(fk)Biomass_stand(fk)

StandStand_name*Region(fk)

RegionRegion_name*Region_source(fk)Source

Collector_author*Source(text)

User evaluation

• Busy schedules– Clients schedules made validating the results of the

calculations difficult– Proper testing requires specific scientific data and an

understanding of the results

• Requirements for the project were to design the calculator– Extra features were added to the project (plant data

base)– More are already requested for next phase

Conclusion

• I have successfully:– Designed a web application to calculate carrying capacity of

herbivores using Tom Hanley’s method– Designed a web interface to search and modify known plant

nutritional data using a relational data base

• I learned:– Programming ASP.NET web pages using C#– Interfacing with SQL Server 2000 to add, edit and delete

relational data– A better understanding of interactions between client side and

server side web applications and Microsoft SQL Server 2000 interactions, could have reduced the time spent on debugging