Environmental Impacts: Urbanization, Algae, and Hydrology

Environmental Impacts of Urbanization

Urbanization presents both potential environmental benefits and significant drawbacks.

Drawbacks of Urbanization

• Intensive urban growth: Can lead to greater poverty.
• Concentrated energy use: Can lead to greater air pollution.
• Physical barriers: Pollution and physical barriers to root growth promote the loss of urban tree cover.
• Deforestation: Deforestation killing the animals that live there.

Benefits of Urbanization

• Higher Productivity: Positive externalities and economies of scale.
• Urban Density: High urban density is benign to the environment.
• Infrastructure: Environmentally friendly infrastructure, such as sanitation, piped water, and green technologies.

Algae Blooms: Causes and Consequences

An algal bloom (also known as a marine bloom or water bloom) is a rapid increase in the population of algae in an aquatic system.

What Causes Algae Blooms?

Algal blooms are the result of an excess of nutrients, particularly phosphorus and nitrogen, entering the water. Higher concentrations of these nutrients cause increased growth of algae and green plants.

Why Are They a Problem?

Algal blooms are a concern because some species of algae produce neurotoxins. These have severe impacts on wildlife and are known as harmful algal blooms.

Marine Reserves and Marine Protected Areas

It is important to distinguish between marine reserves and marine protected areas:

• Marine Reserve: An area where some or all fishing is prohibited for a lengthy period of time.
• Marine Protected Area (MPA): A geographic area with discrete boundaries designated to enhance the conservation of marine resources. An MPA might prohibit activities like oil and gas drilling while allowing fishing.

Water Conservation Strategies for Gardening

To conserve water while gardening, use the following strategies:

• Water at the right time.
• Use the right amount of water.
• Plant flowers that need less water.
• Collect rainwater and reuse old water.

The Hydrologic Cycle and Water Fluxes

The hydrologic cycle consists of several key processes: Evaporation, Condensation, Sublimation, Precipitation, Transpiration, Runoff, and Infiltration.

Key Water Fluxes

1. Surface to Atmosphere: Evaporation
2. Ocean to Atmosphere: Evaporation
3. Atmosphere to Surface/Ocean: Precipitation
4. Surface to Groundwater: Infiltration
5. Groundwater to Surface: Groundwater recharge
6. Groundwater to Ocean: Subsurface flow