Showing posts with label climate change. Show all posts
Showing posts with label climate change. Show all posts

Friday, 12 June 2020

Seagrass: An Overview

Photo of seagrass. From pixabay.com
Aquatic plants and phytoplankton make up the base of the marine food web, making these species vital to the marine ecosystem. Seagrasses are angiospersms (flowering plants) that from vast meadows on the sea bed that photosynthesise to produce oxygen helping to support a vast range of marine organisms.  There are four families of seagrass that are spread all over the globe with roughly 63 species in total that are found in a range of climates. These extensive marine meadows are ecosystem engineers and help to maintain and improve a range of key ecosystem services that benefit both us and marine biodiversity.

Seagrass plays a vital role in reducing coastal erosion as the dense root structures bind the soil together, stabilising the sediment and protecting coastal settlements. The rhizome roots grow horizontally, binding the top soil that often comes loose from waves. This can also reduce the turbidity as less suspended sediment increases the amount of sunlight available to the seabed, in turn increasing seagrass growth. The dense root system can also stabilise any pollutants, such as toxic metals, in the sediment preventing them from travelling with the current. This improves water quality which helps to maintain biodiversity and improve human health, particularly in coastal regions.

As seagrass are photosynthetic, they help to remove carbon dioxide from the atmosphere helping to reduce the impact of the enhanced greenhouse effect. Seagrass meadows account for 10% of carbon storage in the ocean, totalling 27.4 million tonnes annually. This is more than terrestrial forests suggesting that the maintenance of seagrass will have a greater impact on helping to maintain surface temperatures, reducing sea levels rising and reducing ocean acidification. The high amount of carbon is also a reason for high soil fertility within seagrass meadows and has previously been used as fertiliser. This also encourages juvenile plant growth increasing the seagrass population further.

One major threat to segarass meadows is from the boating industry and propellers and anchors can damage the plant or uproot entire sections of the meadow. Segarass provides a physical habitat for many species, including many seahorses, that are at risk of a reduced population, subsequently reducing the genetic diversity of the species. The lack of seagrass growth can also result in eutrophication caused by algal blooms. This causes oxygen in the water to decline reducing biodiversity within these areas even further. Seagrass is also home to several commercial species, such as shrimp and scallops, and the protection of these habitats can help improve and maintain a sustainable fishing industry in coastal region. With proper management, fisherman can have limited access to these areas and quotas should be enforced at the maximum sustainable yield to prevent any damage to seagrass. Reduced seagrass cover not only reduces habitat, but it also decreases the rate of carbon sequestration, a possible increase in turbidity and a decrease in coastal water quality as well as several more ecosystem services being impacted.

To evaluate, seagrass meadows are important marine species that are often over looked and are often seen as seaweed and are therefore not prioritised. However, recently many of these areas have gotten effective management schemes that will hopefully contribute to an improvement in the quality of these habitats. I feel it is important that primary producers within the marine food web are conserved correctly in order to conserve species at higher trophic levels. 

Resources - 


Wednesday, 20 March 2019

The Importance of Peatlands

University of Leeds | News > Environment > Peatland Code ...
Photo of a peatland habitat. from leeds.ac.uk

In the UK, 10% of our land area are covered in peatlands and are vital not only to our economy and wildlife but as a form of carbon sequestration. Despite these factors, peatlands are given little care, unless designated by governments, as they are often just seen as bogs with nutrient rich soil making them ideal spots for the growing agricultural industry. However, the elevated water table means that drainage is required which removes the required vegetation (also know as bog builders)  that have lead to a dramatic decline in global peatland habitats. So what is being done to reverse this and why are these habitats so important?

So peatlands are essentially a soft, nutrient rich soil that forms over a long period of time, in a similar way to coal, under anaerobic conditions. These habitats also acts as a large store of water that leads to the colonisation of Sphagnum mosses that lead to the development of peat habitats such as swamps and wetlands. In the UK there are 10 key peatland Sphagnum species with most common being Baltic Bog-moss that is protected under UK legislation. These mosses have a sponge like structure meaning they store large quantities of water, preventing the surrounding area from drying up. This specific property also helps to prevent any decay and decomposition aiding the accumulation of peat and helping to maintain these diverse habitats. The bog building plants also help to shape the habitat by creating pool and hammock structures that increase the water table, making more water more available to plants on the surface. If these species are removed, it would cause a decline in peat formation, water supply and affect the topography of the habitat.

Global, peatlands are currently storing 500 GT (which is more than all forests) of carbon as a result of peat being made of dead and decaying vegetation which is stored instead of being released into the atmosphere in the form of carbon dioxide. When peatlands are drained and deforested, that stored carbon is then released into the atmosphere so imagine the damage that would be done if all the peatlands around the world were gone? RIP polar bears. These habitats also act as a store of water which not only benefits biodiversity but can also increase ground water levels in the surrounding area and the moss structure helps to filter the groundwater. This means that our water reservoirs would face serious decline in these peatland habitats continue to decrease in size and quality.

Peatlands tend to have a low species diversity due to the habitat creating a small niche so only specialised organism can live there. As the habitat is currently declining many of the species are subsequently following, including the Common Scoter and the Mountain Hare, and the specialised habitat requirements of these species mean they cannot colonise other habitats. As these habitats are declining the competition between and amongst species is increasing therefore reducing the population However, action is being taken especially regarding the protection of breeding birds as several peat habitats, including the North Pennies, have been designated a SPA (Special Protection Area). These areas are maintained and managed in order to increase specific bird populations. Most of these habitats are also listed a SSSI's (sites of special scientific interest) which are areas managed by Natural England due to their biological or geological interest. This ensures that land owners take all the necessary precautions to protect these areas, including many peatland habitats, from damage.

Despite vast restoration efforts, I feel that the importance of these areas is not emphasised to the general public, mainly because they aren't necessarily as aesthetically pleasing as the bright and vibrant tropical rainforests we see. Do I think more could be done? Absolutely. However, the UK government is making good efforts to designated and protect these areas but could invest in future expansion projects to increase the size of our peatlands.


Resources

Wednesday, 20 February 2019

Does Our Environment Affect Our Welfare and Health?

There's no question that we are having a grave impact on our environment whether that is through climate change or habitat destruction. Many of us believe that in order to improve our happiness and welfare we need to have a high income and economic growth in our country but there have been many reports to suggest that there is a strong link between growing the economy and environmental degradation. So what does this mean for our health? Can we really be at our happiest and healthiest with the current trend of over exploitation?

According to the World Bank, in 2014 globally we emitted 36.2 million Ktonnes of CO2 in contrast to the 9 million Ktonnes emitted in 1960 which has made us more vulnerable to respiratory illness. The WHO has linked 3 million deaths each year to outdoor air pollution with reference to illness ranging from asthma and bronchitis to lung cancer. These reports also state these illnesses are higher in industrial areas and larger cities due to excess transport fumes and burning of fossil fuels. There has also been a link between high concentrations of air pollution and cardiovascular illness which puts us at greater risk of heart attack, stroke and angina. One way this occurs is through particulate matter entering the blood stream, restricting the movement of blood vessels, increasing blood pressure and therefore increasing our risk of suffering a heart attack.

Sunlight provides us with vitamin D which is needed to regulate calcium and phosphate within the body, helping to maintain healthy bones and muscles. We as humans require 10 micrograms of vitamin D a day, most of which we are supposed to get naturally through sunlight meaning we do have to step out of the house occasionally. A lack of vitamin D in extreme cases can cause rickets in children that leads to weak bones and deformities. This causes a high number of bone fractures and can eventually cause a curvature of the spine, leading to a permanent disability. Low vitamin D can also cause osteomalacia, which is similar to rickets, in adults causing bones to soften. With 1 in 5 people in the UK having low vitamin D levels, it is important we spend more time outdoors (and maybe consider a supplement in winter).

There have also been studies suggesting a link between time outside and an improvement in mental health with studies showing time outdoors reduces stress and reduces the symptoms of depression and anxiety. Scientists have suggested that urban and man made environments has 'constant simulation' that leads to mental fatigue, making those living in cities at greater risk of mental illness. Those living in rural areas also have better sleep with less noises keeping them awake. This will help to improve concentration, lower stress and improve moods which will allow people to be more productive.

There is also the obvious benefit that walking in a natural environment keeps us active, aids weight loss and maintains a healthy heart. Sitting down for too long can cause a decline in bone density and increase blood pressure after deposits in the blood vessels are not removed. All of these factors have been linked to a lower life expectancy by increasing our risk of stroke, heart disease and diabetes just to name a few.

So we all need to get outside in nature to help improve our health and wellbeing. However, I'm not saying that if you live in a city you're going to get ill and live a shorter life because that's not the case. Most large cities have parks and open spaces you can visit and city councils should be turning old sites into open spaces to encourage the urban population the get out and appreciate nature and we should all be doing our bit to protect it to protect the health of the future generations.


References
https://ourworldindata.org/air-pollution#death-rates-from-air-pollution
https://www.bhf.org.uk/informationsupport/support/practical-support/air-pollution
https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
https://patient.info/health/osteoporosis-leaflet/vitamin-d-deficiency

Wednesday, 9 January 2019

Are Fireworks Damaging Our Environment?


Happy new year! Our beautiful planet has taken another journey around our sun meaning that we celebrate with over the top and elaborate firework displays and excessive drinking. Whilst watching the London fireworks on TV, I couldn't help but notice the large amount of smoke being emitted which got me thinking could these beautiful sparks of light actually be having a big impact on the environment?

A picture of fireworks. From pixabay.com

Before looking at the impact I was curious what these were actually made of. In the simplest form, fireworks are tubes filled with gunpowder, wrapped in flash paper and attached to a fuse, hence the explosion. However, to create the sparkle and the colour aluminium, iron, steel, zinc, or magnesium are added as these ensure that fireworks will burn for longer and brighter. Compounds of strontium, lithium, sodium, barium or copper are added to change the colour as these react with heat differently to produce different coloured flames, thus creating the beautiful displays we see twice a year. These additions are the biggest concern as in high concentrations, they can be toxic for both humans and wildlife. The fireworks create particulate matter containing the toxic elements that will eventually settle on land and, if landed on soil, can be taken into the plant system via the roots and enter the food chain via bio-magnification. Aluminium alone can affect the functions of gills in fish as it acts as an inhibitor for the enzyme responsible for the uptake of ions and will therefore reduce fish populations and any predators feeding on the poisoned fish.

Another issue is the smoke caused as it increases particulate matter levels and increases carbon dioxide concentrations within our atmosphere. Particulate matter is a collection of particles (under 100 micrometers) that are either produced naturally or, in the case of fireworks, are produced from chemical reactions. Minerals (including aluminium, silicon, iron and calcium) are producers of particulate matter and, as previously stated, some of these are included in the makeup of fireworks but this composition varies depending on colour. The monitoring of particulate matter has shown that pollution episodes (above average concentrations) occur around January and November implying there may be a link between New Year and Bonfire night. During these winter months, high PM concentration have been linked to temperature inversion that are responsible for trapping pollution at ground levels, in turn increasing our exposure time. There are a range of health impacts ranging from respiratory illness to affecting the cardiovascular system with these risks being greatest during inversions which is shown by the increase of breathing problems of over 30% during Diwali. However, there is also a large environmental impact the first one being the impact of photosynthesis as PM deposits on the leaves of green plants reducing the contact to sunlight. This can reduce the rate of plant growth and therefore lessening the amount of food available to primary consumers. This can affect of the rest of the food web as it reduces energy available for higher tropic levels (basically reducing food for top predators) especially if the primary consumer populations are affected.

The chemical process of lighting the gun powder has been linked to the pollution of sulphur dioxide and nitrogen dioxide, both of which are major polluting gases. Sulphur dioxide is directly linked to the production of acid rain that can corrode metal and limestone structures as well as the exoskeletons of invertebrates. As many small invertebrates are the basis of any food web, this can again affect higher tropic levels and affect the food availability within the ecosystem. This can also affect the pH of water bodies and has the potential to cause ocean acidification which is a cause for coral bleaching. As our coral reefs are currently in decline shouldn't we be doing everything in our power to reduce acid rain, especially for things that are not strictly necessary?  Nitrogen dioxide has been linked to increased eutrophication, decreasing the sunlight available to a water supply by the growth of algal blooms. This causes a decline in oxygen from a lack of photosynthesis affecting the populations of marine organisms thus reducing biodiversity. This, again, can affect human health and can cause nitrogen dioxide poisoning as it can irritate the mucous membrane in the lungs.

So with these major environmental impacts shouldn't we be focusing on reducing our use of fireworks rather than spending millions on elaborate firework displays every year? With so much advancement in scientific knowledge, it does seem strange to me that we have not found a more sustainable alternative, despite the fact that firework displays are unnecessary to our well being but I can see that it is a tradition and culturally we associate these with celebrations. With the development of renewable energy sources, light and laswer shows could be an alternative if done safely. With climate change being on the tip of everyone tongue, I think we should be looking at smaller issues, like fireworks, in order to help the bigger picture.


References