Through United Nation Sustainable Development Goals, Goal #12, several students from two different countries are investigating the connection between oysters and limestone. This goal promotes responsible production and consumption.

Through United Nation Sustainable Development Goals, Goal #12, several students from
two different countries are investigating the connection between oysters and limestone. This goal
promotes responsible production and consumption. Oysters are the keystone species in many
aquatic ecosystems. Limestone, on the other hand, is a sedimentary rock that is found in coastal
areas. There are several studies regarding the protection and preservation of ecosystems
containing oysters and how we improve the overall population. Oysters are filter feeders and
improve the water quality. Limestone properties intertwine with the life cycle of oysters.
Unfortunately, the life cycle of oysters has been disturbed by many different environmental
factors, and put the population on the verge of extinction.
Oysters are in danger of extinction in the Chesapeake Bay for several reasons. Two of
which are overfishing and pollution. The Chesapeake Bay Foundation and other groups have
created a solution to this by creating oyster balls for larvae to grow on, using reusable shells that
you can make the concrete oyster balls out of, and regulating and reducing oyster farming. The
oyster balls are big “reefs” made of concrete that oyster larvae can grow on and start a habitat in
order to grow the oyster population. These habitats are simple to construct, being made of
recycled oyster shells, instead we can conserve our natural resources. However, according to
Kevin Boyle, an oyster farmer from ShoreThing Oyster Farm, “ Oyster reef balls are not good for
farming oysters but they can be good for [an oyster] habitat. They are too big and heavy to be
used for farming.” Oyster farmers will not catch any oysters that are on these balls and the
oysters can be protected. Another solution that has come up through years of data collection is to
enact laws that regulate overfishing of oysters in the Chesapeake Bay. The Virginia Marine
Resources Commission stated in the chapter, Pertaining To Restrictions On Oyster Harvest, that
“ This chapter establishes times of closure and other restrictions, for conservation purposes, on
the harvest of oysters from all oyster grounds in the tidal waters of the Commonwealth.”
Limestone is classified as one of the most common rocks. It is mainly composed of the
chemicals calcium and bicarbonate. The limestone is created in a body of salt water, when there
is a loss of carbon dioxide. While replenishing the CO2, calcite is made, and then the limestone
starts to form. Later on the fossils of marine life join in giving the rock its texture. As our world
evolves the need for roads and buildings are increasing, therefore requiring the need for mass
amounts of cement. The key ingredient in cement is limestone, making up about thirty-five
percent of the mixture. The amount of limestone we have cannot keep up with the demand
therefore it is forcing us to export it from foreign countries. Portugal is one of the limestone
suppliers. They have plants to use it to make a thick binding paste called mortar as well as ready
mix cement. Unfortunately, the machines that we use to farm the limestone is releasing carbon
dioxide into the water, harming the marine life as well as causing sinkholes in the surrounding
Because limestone is one of the main ingredients in cement, it can be used to create
oyster reef balls, which in turn can allow the population of oysters to flourish. Natural oyster
reefs are declining at an alarming rate and therefore man made oyster reefs are becoming more
prevalent in bays. Another reason why oyster reef balls and limestone are so important is because
oyster reefs provide habitats for countless other species. Kevin Boyle, an oyster farmer from
ShoreThing said, “ The farm is an incredible piece of habitat for other animals that live in the
Bay. I see tons of rockfish, perch, and crabs around the boat when I go out to harvest oysters
from the cages we grow them in. If it weren’t for my oysters and the cages they are grown in,
those animals would not be there.” Oysters are impacted greatly by the things that move around
them, like fish. Oyster reefs also filter and purify the water, making this another reason why so
many other species live in or around oyster reefs. Also, because oyster shells and limestone are
made of the same thing, calcium carbonate, the concrete that comes from limestone can be used
to create more oyster reef balls. In addition, excess oyster shells, because they are made up of
calcium carbonate, can be ground up to create concrete that is used for artificial oyster reefs.
During limestone mining, lots of runoff containing calcium carbonate goes from the mountain to
the ocean, and this calcium carbonate can be used to make more oyster shells. Oysters use this
limestone to create shells for themselves. There are a variety of different ways in which
limestone and oysters are interconnected, such as artificial reefs, and oyster shells being made up
of calcium carbonate, a material found in limestone.
There is an environmental connection between oysters and limestone. We can use
limestone to create concrete, which can be used to build oyster reef balls. These structures can
provide a habitat for up to hundreds or even thousands of oysters. Additionally, oysters, because
they are made out of calcium carbonate, can be turned into concrete themselves. The disposal of
oyster shells ultimately leads to a major decrease in the population. The simple act of
redistributing the shells into the ocean can balance out the ecosystem. Goal #12 talks about
sustainable consumption and production, which is very present in oysters and limestone.
Limestone can be sustainably produced and consumed by limiting the amount of runoff of
calcium carbonate in limestone mining. Oysters also can be sustainably consumed and produced,
by reusing oyster shells and limestone.


Alunos envolvidos no projeto: Alex Molfetas; Ash Rauch; Bridget Levesque; Beatriz Sousa; Gabriela Delgado; PJ Milton

Escola: Externato Cooperativo da Benedita

Data: 06.04.2018

Partilha esta reportagem em