Drivers of Biodiversity Decline

On a world-wide basis, the five biggest (in order of importance) threats to biodiversity are:- 1. human changes in land and sea use; 2. human water consumption; 3. degradation of peatlands and bogs; 4. plastic pollution and 5. invasive species (https://www.theguardian.com/environment/2021/dec/26/bogs-banks-and-bubble-barriers-five-great-projects-to-protect-nature-aoe). All 5 threats are well-recognised and conservationists are developing some interesting techniques, when attempting to deal with them. It is now recognised that the North American grassland plants are under considerale threat due to land use changes. The Southeastern Grasslands Initiative, recognising that financial support is very limited, has helped to set up conservation seed banks. The possibility consequently exists that plants could be reintroduced. Each year since the 1980s, 1% more water has been needed. Similar annual increases seem to be likely into the forseeable future. It has, however, been recognised that 80% of untreated waste water is currently allowed to simply flow back into ecosystems. Conservationists are looking at developments in Israel that clean and reutilise waste water. This might cut down the need for desalination plants. Peatlands and bogs only cover around 3% of the Earth's land surface. They store, however, almost 550bn tonnes of carbon, which is more than all the planet's forests. There are, consequently, initiatives (such as in Northern England) to restore degraded peatlands. Its impact on atmospheric carbon dioxide might well be greater than that acheived by planting trees. Plastic pollution in the oceans is scheduled (without intervention) to triple over the next 20 years. There are, consequently, many initiatives to remove plastics from the seas, including removing it from the rivers that feed them. Most of the focus, however, appears to be on large items like bottles and stirrers. Less attention has been paid to microplastics from the tyres and braking systems of motor vehicles. These will still be produced, even if everyone switches to using electric cars. Invasive species (e.g. rats, pigs etc) are often accidentally or deliberately introduced by humans. It has now been demonstrated that more than 100 threatened island bird, mammal and reptile species have benefited from programmes that eradicated invasive mammals. Conservation often requires operatives to become rat-catchers. Recent developments in this area include the development of the New Zealand Predator-Free zone. There is obviously lots of work that has to be done in these 5 areas, if serious loss of biodiversity is to be avoided.