10. (a) Explain the following terms as used in ecology - Leaving Cert Biology - Question 10 - 2017

An ecosystem is a community of living organisms—such as plants, animals, and microorganisms—interacting with each other and their physical environment. This includes both biotic components (living things) and abiotic components (non-living elements like air, water, and minerals) that create a complex web of life, supporting biodiversity and individual species' survival.

Conservation is the management of the environment and natural resources to prevent over-exploitation, ensure sustainability, and maintain biodiversity. It includes efforts to protect species, restore natural habitats, and reduce the impact of human activity on the planet in order to preserve ecosystems for future generations.

1. Dublin has a large population, leading to a significant amount of domestic waste that needs disposal, thus creating a demand for an efficient waste management facility.
2. The city lacks available space for traditional landfill sites, making it necessary to implement an incineration solution to handle increasing waste volumes and reduce energy waste.

Advantage: Incineration helps to significantly reduce the volume of waste, converting it into energy that can be utilized for power generation, thereby contributing to energy sustainability. Disadvantage: The process can produce harmful emissions and pollutants, which may pose health risks to nearby communities if not adequately controlled and managed.

Microorganisms play a crucial role in waste disposal by breaking down organic matter, thus facilitating decomposition. They help recycle nutrients back into the ecosystem and maintain the health of soil and other natural environments by acting as decomposers.

A pollutant is any substance that, when introduced into the environment, causes adverse effects on ecosystems, human health, or the climate. Pollutants can be volatile chemicals, metals, or waste products whose accumulation can disturb ecological balance.

One significant pollutant from agriculture is nitrogen fertilizer, which, when washed into waterways, can cause eutrophication. This leads to excessive growth of algae, depleting oxygen levels in water bodies and harming aquatic life.

The control of nitrogen fertilizer pollution can involve implementing responsible agricultural practices such as precision farming, where fertilizers are applied based on soil nutrient tests to prevent over-application. Additionally, buffer strips and other natural barriers can be utilized to reduce runoff into water bodies.

1. Lynx (predator)
2. Snowshoe hare (prey)

The x-axis represents time, while the y-axis represents the population numbers of the predator and prey species. The curves show that as the prey population increases, the predator population also rises, followed by a decline in prey due to increased predation, which subsequently leads to a decline in the predator population as food becomes scarce.

The fluctuations in a predator-prey relationship graph show a cycle where the prey population increases as food resources are plentiful. This abundance attracts more predators, which leads to increased predation. However, as predator numbers grow, they consume more prey, leading to a decline in the prey population. Following this decline, predator numbers also begin to drop due to lack of food until the cycle starts again.

Predator-prey relationships are essential for maintaining ecological balance. Predators help control prey populations, preventing overgrazing or overpopulation that can result in habitat degradation. This dynamic helps ensure that ecosystems remain diverse and resilient, contributing to overall biodiversity.