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Topic 4: Aquatic Systems

Topic 4: Aquatic Systems

This is a new emphasis in the course, requiring the study of aquatic food production systems. They have regularly been included in exam questions and so this was a largely hidden part of the curriculum. In this topic students will need to study several case studies.

Topic 4 looks at the hydrological cycle and ocean circulation and it's a good idea to consider how this interacts with soil. It considers issues around access to water and the conflict that can arise from this but also the solutions needed. Finally it considers how food is produced / harvested from aquatic systems and the environmental issues associated with this. Aquaculture provides some students with hope.

Significant Ideas:

  • The hydrological cycle is a system of water flows and storages that may be disrupted by human activity.
  • The ocean circulatory system (ocean conveyor belt) influences the climate and global distribution of water (matter and energy).
  • The supplies of freshwater resources are inequitably available and unevenly distributed, which can lead to conflict and concerns over water security.
  • Freshwater resources can be sustainably managed using a variety of different approaches
  • Aquatic systems provide a source of food production.
  • Aquaculture provides potential for increased food production.
  • Unsustainable use of aquatic ecosystems can lead to environmental degradation and collapse of wild fisheries.
  • Water pollution, both to groundwater and surface water, is a major global problem, the effects of which influence human and other
  • biological systems.

Recommended Teaching Time (not including practicals): 15 hours

4.1 An Introduction to Water Systems - The Hydrological Cycle

In this short introduction to water systems, we will learn about the hydrological cycle as a system, identifying stores and flows in the system and how humans impact the system. The next part of this...

4.1 Ocean Currents

In a past iteration of the IB Environmental Science Guide, students needed to know the different types of ocean current and in the 2010 ESS Guide there was no mention of ocean currents.Now, students should...

4.2 Access to Fresh Water - the problems

It is important to contrast why different locations may be suffering from the challenges of access to fresh water. Freshwater is unequally distributed around the world (some areas are dry and others,...

4.2 Access to Water - Conflict

There is a clear need for a case study on when water resources can lead to conflict between human populations. This year I have decided to keep the scale of this case study down and take a quick approach...

4.2 Access to Water - Sustainability Solutions

This is a cool, interesting topic which students will enjoy as it is solutions focused. I wanted to reflect this thinking and provide students with a fun way of researching and remembering different ideas...

4.3 Aquatic Food Production Systems

This is quite a new topic for ESS. Although teachers had the option, in the previous syllabus, to teach an aquatic food production system, I have not found this a common option. Past case studies have...

4.3 Controversial Harvesting of Aquatic Species

This is brand new in the syllabus and a topic which can excite strong emotions. Personally I find the topic very difficult. Some teachers might choose to show the powerful documentary The Cove but I find...

4.4 Water Pollution - Introduction

By the time I come to teach this topic, my students already know about biological oxygen demand, sampling water, indicator species and eutrophication but this depends on the order of the units that you...

4.4 Water Pollution - Eutrophication

Eutrophication is a very common environmental problem and also has appeared on ESS exams many times. Past paper case studies include May 2011 about Sweden and Inle Lake, Myanmar (Burma) in May 2015. By...

4.4 Water Pollution - Measurement

In this section we shall look at how water pollution can be monitored and measured using direct and indirect measures. This section links strongly to 1.5 Humans and Pollution, 2.5 Investigating Ecosystems...

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