Which factor might indicate a need for integrated management of a water body?

The choice indicating a need for integrated management of a water body is excessive aquatic weed growth. This factor is a significant concern because it can lead to numerous ecological issues. Excessive growth of aquatic weeds can disrupt water flow, reduce oxygen levels in the water, and hinder the overall health of the aquatic ecosystem. When weeds proliferate, they can outcompete native plant species, leading to reduced biodiversity and habitat degradation.

In addition, high levels of aquatic weeds can negatively impact recreational activities such as swimming, fishing, and boating, which might warrant further management attention. Integrated management approaches, which combine various methods for controlling these weeds, become important in addressing not only the immediate problem of excessive growth but also the broader implications for water quality, biodiversity, and user enjoyment of the water body.

The other factors, while they can reflect aspects of the ecosystem or usage of the water body, do not immediately indicate a clear need for integrated management strategies in the same way that excessive aquatic weed growth does. They might even suggest healthy ecosystems or well-maintained areas, which typically do not require the same level of intervention.