7 3 biodiversity and the effect of human interaction on ecosystems

Biodiversity is the variety of different species found in a habitat. This includes, e.g. the number of different species, the size of each population and the differences between individuals of a species.

The benefits of high biodiversity include:

False. Low biodiversity decreases ecosystem stability. This is because when fewer species are present a change in one species is more likely to have a significant impact on other species.

Different species depend on each other for:

False. ** In a biodiverse ecosystem species will have multiple food sources**, so the loss of one food source will have minimal effects on dependent species.

Human activities that reduce biodiversity include:

Deforestation reduces biodiversity by destroying forest habitats that contain high biodiversity.

Maintaining biodiversity is important for humans because we rely on many other species to survive, such as for oxygen production, food crop pollination, and medicine.

Human activities that result in water pollution are:

Consequences of untreated sewage runoff into water systems include:

Acidic gases, e.g. sulfur dioxide, can combine with water droplets in the air to form acid rain.

Consequences of acid rain pollution include:

Discarded rubbish can impact the environment as follows:

Pollution kills plants and animals, which can reduce biodiversity.

Human activities that require increasing land use are:

False. ** Habitat destruction reduces **biodiversity.

A peat bog is an area of land that is waterlogged and acidic. The organic matter in a peat bog is known as peat, and consists of dead plants that have not decayed fully due to low pH and a lack of oxygen.

Peat bogs store carbon within the tissues of partially decomposed plant matter. Because the conditions are unsuitable for decay this carbon remains locked up in peat.

Peat bogs are being destroyed because:

Peat bog destruction reduces biodiversity by decreasing available habitat for many species of animals, plants, and microorganisms.

Peat bog loss increases atmospheric carbon dioxide as follows:

False. ** Peat is a non-renewable** energy source due to the long time it takes to form.

Deforestation is the process of clearing trees, usually on a large scale. This is often done to make way for building or agriculture.

Two main reasons for deforestation in tropical areas are to:

A biofuel is a fuel derived from living matter, such as plant material.

Environmental effects of deforestation include:

False. ** Deforestation increases **atmospheric carbon dioxide concentration. This is because living trees absorb carbon dioxide during photosynthesis; removal of these trees therefore reduces the rate at which carbon dioxide is removed from the atmosphere.

False. Deforestation affects both plant and animal species, potentially leading to their extinction.

The greenhouse effect occurs when radiation from the sun is absorbed by greenhouse gases in the earth's atmosphere. This traps heat and warms the atmosphere.

Two greenhouse gases are: (There are other greenhouse gases but these are the two listed in your specification.)

Global warming refers to the long-term increase in the earth's average temperature, primarily due to human activities that increase the levels of greenhouse gases in the atmosphere.

Some consequences of global warming include:

False. ** Global warming is increasing ocean temperatures**, leading to impacts such as melting polar ice caps, rising sea levels and coral bleaching.

A scientific consensus, in the context of global warming, describes the fact that almost all scientists agree that global warming is happening and that human activities are largely responsible for the most recent warming

False. Humans can have both positive and negative interactions with ecosystems.

Programmes designed to reduce negative human impacts on ecosystems include:

Endangered species are plants or animals at risk of extinction.

Breeding programmes can be used to increase the reproductive success of endangered species in captivity; this can help to increase their population size and genetic diversity.

Habitat regeneration is the process of restoring damaged or destroyed habitats to support native species.

False. Reintroduction of field margins and hedgerows in agricultural areas increases biodiversity.

A monoculture is the agricultural practice of growing only one type of crop in a field.

Field margins and hedgerows benefit biodiversity by providing habitats and corridors for wildlife in agricultural areas.

The main goal of reducing carbon dioxide emissions is to slow climate change, which can negatively impact ecosystems and biodiversity.

Recycling helps biodiversity by reducing the waste dumped in landfill, which can destroy habitats and cause pollution.