Sand Mining And The Aquatic Ecosystem: Impacts and Solutions.
When we talk about mining, the first things that will probably come to our minds are gold, rare earth metals, coals other metals. Sand would probably not come to mind, but they are one of the most consumed natural resources and are mined heavily.
Sand is a loose granular material made up of silicone dioxide in the form of quartz. The composition, texture, and color of the sand differ with location.
Though underrated, sand is one of the most widely used natural resources on earth; it has wide use in building and road construction, for producing glass for building and automotive service, or glass containers for foods and beverages; it is also used in making computer chips, toothpaste, cosmetics, paper, plastics and paint and a lot more. This means that sand is vital to our everyday lives.
UNEP Geneva 2022 Press release stated that we consume over 50 billion tons of sand each year, making it the second most consumed natural resource after water. With increasing urbanization and population growth, the amount of sand consumed increases yearly.
Sand mining is the extraction of sand from an open pit, sometimes called a sand pit. Sand can also be mined from beaches and inland dunes or obtained from ocean or riverbed dredging. It is usually done to provide sand for construction, and land reclamation, such as in places like Singapore, and as raw materials for other industrial operations or processes. It accounts for 85% of all global mineral exploration; surprisingly, it is also the least regulated.
Sand mining also presents an opportunity to extract other minerals such as rutile and ilmenite, which contain industrial elements like titanium used in prosthetics, mobile phones, and other high-performance products.
The use of sand varies with the sand type and location; not all sand is suitable for all uses. For instance, desert sand is not ideal for construction because of its well-rounded grain due to erosion. Marine sand is also unsuitable for construction because the salt content can corrode metals; therefore, sand from pits on land, riverbed, and seabed are indiscriminately mined.
Effects of sand mining on aquatic ecosystem
Impact on aquatic biodiversity
Sand mining has a significant impact on biodiversity, mainly aquatic biodiversity. Many animal species depend on sandy beaches for nesting and reproduction. The dredging of this soil, which leads to the removal of floodplain habitat, will significantly impact species population.
The Gharial, also known as the fish-eating crocodile in India, has recorded a drastic decline in population due to habitat loss from sand mining; this species has been listed as critically endangered on the IUCN Red List.
Aside from the scrapping of bottom sediment, dredging also causes water turbidity, which harms organisms such as corals. In addition, sand mining can lead to reduced fish diversity and abundance and changes to riverside vegetation.
Alteration of hydrological function
Sand mining does not only degrade the quality of the water. It also alters the physical properties of the water. It causes river pollution and changes the river’s acidity (pH).
It can also lead to changes in river flow, increasing temperature, and the concentration of nutrients and pathogens, leading to an algal bloom.
Excessive removal of sediment, which happens during mining, can change the structure and form of the riverbed itself. Other impacts of sand mining on river hydrology include the loss of aquifer storage, coastal erosion through lowering the riverbed, and reduced flood regulation capacity leading to increased flood frequency.
Solution strategies for sand mining
One major solution to sand mining is incorporating a circular economy approach. A large percentage of construction demolition waste is recyclable; providing incentives for using construction waste will go a long way in reducing the pressure on riverbed sand.
The UN Report on Sand and Sustainability 2022 has provided ten strategic recommendations to avert a sand crisis and create an equilibrium between the demand for sand for industrial processes with the protection of the environment.
