Human activity impacts on surface processes - Leaving Cert Geography - Question 2C - 2019

Introduction

Human activities significantly affect river processes through various means, including urbanization, agriculture, and industrial practices. This examination focuses on how these activities alter natural river dynamics and their repercussions.

Identification of the Impact

One specific impact of human activity on river processes is the alteration of natural flow patterns caused by dam constructions. Dams can change the sediment transport and the ecological health of the river while influencing flood cycles.

Examination of the Impact on River Processes

1. Hydrological Changes: Dams regulate water flow, leading to increased flooding downstream during heavy rainfall, while limiting flow in drier periods. These alterations can disrupt habitats and decrease the natural variability that ecosystems depend on.

2. Sediment Transport: Human-made structures like weirs impede the natural movement of sediments, causing sediment buildup in some areas and erosion in others. This can alter river banks and affect the surrounding flora and fauna.

3. Water Quality: Urban runoff containing pollutants can degrade water quality, affecting aquatic life and making the water unsafe for human consumption. This situation can lead to a decline in biodiversity within the river ecosystem.

4. Ecological Disruption: Changes in water temperature and chemistry due to industrial discharges can have a detrimental impact on the aquatic species, leading to shifts in community structures.

5. Case Study Example: The River Shannon in Ireland has experienced significant impacts from human activity, including damming and urbanization, leading to various ecological challenges.

Conclusion

In conclusion, human activity has profound and multifaceted impacts on river processes. While some interventions aim to control flooding and manage water resources, they can inadvertently cause disruption to the natural functions of river ecosystems, highlighting the need for sustainable management practices.