Creating a comprehensive Entity$-$Relationship Diagram $($ERD$)$ for EcoAlert based on the provided information requires identifying key entities, their attributes, and relationships. Here's a simplified representation:

Entities:

User:

UserID $($Primary Key$)$

Username

Password

Email

UserType $($User$/$Admin$)$

PublicDashboard:

DashboardID $($Primary Key$)$

Data $($Real$-$time environmental data$)$

NewsPage:

NewsID $($Primary Key$)$

Content

Category $($Floral threat, Fauna threat, Nature disaster, People accident$)$

MultimediaSupport:

MediaID $($Primary Key$)$

IncidentID $($Foreign Key$)$

Type $($Text$,$ Photo, Video, Voice, Gallery$)$

FileURL

Incident:

IncidentID $($Primary Key$)$

LocationLongitude

LocationLatitude

UserID $($Foreign Key$)$

EmergencyContact:

ContactID $($Primary Key$)$

AgencyName

ContactNumber

Report:

ReportID $($Primary Key$)$

IncidentID $($Foreign Key$)$

Date

Time

Evidence

UserID $($Foreign Key$)$

Relationships:

User$-$NewsPage Relationship:

One user can submit multiple incidents on the News Page.

One News Page entry is associated with one user.

User$-$Incident Relationship:

One user can be associated with multiple incidents.

Each incident is reported by one user.

Incident$-$MultimediaSupport Relationship:

Each incident can have multiple multimedia entries.

Each multimedia entry is associated with one incident.

Incident$-$EmergencyContact Relationship:

Each incident is associated with an emergency contact.

Each emergency contact can be related to multiple incidents.

Report$-$Incident Relationship:

Each report is associated with a specific incident.

Each incident can have multiple reports.

User$-$Report Relationship:

One user can generate multiple reports.

Each report is associated with one user.

Note: This ERD is a simplified representation and may need further refinement based on additional requirements or specific constraints in your application. Also, consider the cardinality and optionality of relationships to ensure accuracy in representing the data model.