Habitat destruction

Geological processes, climate change,[2] introduction of invasive species, ecosystem nutrient depletion, water and noise pollution are some examples.

Fragmentation and loss of habitat have become one of the most important topics of research in ecology as they are major threats to the survival of endangered species.

[7] South and East Asia—especially China, India, Malaysia, Indonesia, and Japan—and many areas in West Africa have extremely dense human populations that allow little room for natural habitat.

[7] Regions of unsustainable agriculture or unstable governments, which may go hand-in-hand, typically experience high rates of habitat destruction.

[11] But included in that 10–20% of land is the approximately 9 million square kilometers of seasonally dry-lands that humans have converted to deserts through the process of desertification.

[13] In the United Kingdom, there has been an increase in demand for coastal housing and tourism which has caused a decline in marine habitats over the last 60 years.

The rising sea levels and temperatures have caused soil erosion, coastal flooding, and loss of quality in the UK marine ecosystem.

[16] Demographic drivers include the expanding human population; rate of population increase over time; spatial distribution of people in a given area (urban versus rural), ecosystem type, and country; and the combined effects of poverty, age, family planning, gender, and education status of people in certain areas.

[6] This may explain why human population density accounts for 87.9% of the variation in numbers of threatened species across 114 countries, providing indisputable evidence that people play the largest role in decreasing biodiversity.

The main economic factors included commercialization and growth of timber markets (68%), which are driven by national and international demands; urban industrial growth (38%); low domestic costs for land, labor, fuel, and timber (32%); and increases in product prices mainly for cash crops (25%).

Physically larger species and those living at lower latitudes or in forests or oceans are more sensitive to reduction in habitat area.

Even the simplest forms of agriculture affect diversity – through clearing or draining the land, discouraging weeds and pests, and encouraging just a limited set of domesticated plant and animal species.

Road construction has the largest feedback effect, because it interacts with—and leads to—the establishment of new settlements and more people, which causes a growth in wood (logging) and food markets.

When these industries become commercialized, they must become more efficient by utilizing larger or more modern machinery that often has a worse effect on the habitat than traditional farming and logging methods.

For example: When a habitat is destroyed, the carrying capacity for indigenous plants, animals, and other organisms is reduced so that populations decline, sometimes up to the level of extinction.

[48] Habitat destruction can vastly increase an area's vulnerability to natural disasters like flood and drought, crop failure, spread of disease, and water contamination.

[16][page needed] On the other hand, a healthy ecosystem with good management practices can reduce the chance of these events happening, or will at least mitigate adverse impacts.

Habitat destruction has altered nitrogen, phosphorus, sulfur, and carbon cycles, which has increased the frequency and severity of acid rain, algal blooms, and fish kills in rivers and oceans and contributed tremendously to global climate change.

[7] Other ecosystem services that are diminished or lost altogether as a result of habitat destruction include watershed management, nitrogen fixation, oxygen production, pollination (see pollinator decline),[54] waste treatment (i.e., the breaking down and immobilization of toxic pollutants), and nutrient recycling of sewage or agricultural runoff.

[7] The loss of trees from tropical rainforests alone represents a substantial diminishing of Earth's ability to produce oxygen and to use up carbon dioxide.

[50] The loss of biodiversity may not directly affect humans, but the indirect effects of losing many species as well as the diversity of ecosystems in general are enormous.

When too much biodiversity is lost, a catastrophic event such as an earthquake, flood, or volcanic eruption could cause an ecosystem to crash, and humans would obviously suffer from that.

[55] Loss of biodiversity also means that humans are losing animals that could have served as biological-control agents and plants that could potentially provide higher-yielding crop varieties, pharmaceutical drugs to cure existing or future diseases (such as cancer), and new resistant crop-varieties for agricultural species susceptible to pesticide-resistant insects or virulent strains of fungi, viruses, and bacteria.

[16][need quotation to verify] The rapid expansion of the global human population is increasing the world's food requirement substantially.

Commercial farmers are going to become desperate to produce more food from the same amount of land, so they will use more fertilizers and show less concern for the environment to meet the market demand.

However, the United Nations Environment Programme report on "Making Peace with Nature" released in 2021 found that most of these efforts had failed to meet their internationally agreed upon goals.

[19] This concept, along with many other results of tropical deforestation from the Geist and Lambin study, can easily be applied to habitat destruction in general.

These can reduce damage and erosion while simultaneously providing ecosystem services such as food production, nutrient and sediment removal, and water quality improvement to society[59] Preventing an area from losing its specialist species to generalist invasive species depends on the extent of the habitat destruction that has already taken place.

[45] Governmental leaders need to take action by addressing the underlying driving forces, rather than merely regulating the proximate causes.

In a broader sense, governmental bodies at a local, national, and international scale need to emphasize: It is argued that the effects of habitat loss and fragmentation can be counteracted by including spatial processes in potential restoration management plans.