Phosphate Mining in Chengdu, China

the mining site - greenpeace.org

What's happening? -

An Environmental research group have discovered that phosphate mining in the Longmen Mountian in the Sichuan province of China, greatly increasing the siesemic area's risk to earthquakes and natural disasters and moreover, endangering wildlife reserves and a nearby population of pandas. The phosphate is used in chemical fertilizers which are used to allow for China's mass plant production to feed a rapidly growing population. Plants need phosphate in order to stimulate leaf and root growth and to prevent disease, and China's low-phosphate soil means fertilization is necessary for efficient plant growth.

What threat does phosphate mining cause?

The area surrounding the phosphate mining site is prone to earthquakes and landslides and was hit by a devastating earthquake in 2008. A Greenpeace East Asia report highlighted the role that the phosphate mine has in lowering the stability of the mountain geology, imposing a greater risk of landslides, earthquakes and natural disasters to the area, its inhabitants and wildlife.

pandas are being threatened by the mining

Moreover, the phosphate mining activity is having a detrimental impact on a nearby nature reserve which is home to 11 endangered pandas. In 2012, the province's government lowered the size of the reserve's area to allow for increased phosphate mining, greatly reducing the panda's habitat and the survival chances of the species.

What can be done to reduce this threat?

- Appeals need to be made to the Sichuen Province Governement to halt mining in order for a full risk analysis to be carried out so measures can be taken to ensure that phosphate mining is strictly regulated and done without risk to the area.

- Plant nutritienist, Zhang Fusuo, has reported that China uses phosphate based plant fertilizer at levels much higher than actually nescessary. China's phosphate fertilizer use could be reduced by: encouraging farmers to use fertilisers at an appropriate level and to use 'build-up' measures to keep the soil phosphate at an optimum level; using technology to manipulate the chemistry of the layer of soil surrounding the roots, the rhizosphere, to increase the percentage of phosphate in the soil plants can uptake; using animal manure as a fertilizer, which would also greatly decrease the pollution of water ways caused by run-off of animal manure which triggers harmful algal bloom, killing fish and endangering the area.

sources:
Greenpeace - the campaigning organisation have highlighted and provided information on the issue in their magazine and blog. http://www.greenpeace.org/international/en/news/Blogs/makingwaves/uglyfood-the-other-truth-about-chemical-ferti/blog/44782/
Nature - this article contains in-depth information on the phophate fertilizer issue in China

Ozone Depletion

What is the ozone layer?
The ozone layer in the stratosphere is vital for life on earth because ozone (O₃) absorbs the sun's high energy UV-C radiation (100-280 nm) and some UV-B radiation before it reaches earth. This UV radiation can damage life on earth by causing:

• DNA mutation by breaking hydrogen bonds
• skin cancer (due to dna mutation)
• Cataracts
• Crop failure (due to dna damage and interaction with plant growth regulators) 
• Sunburn/ Epidermal hypoplasia

How is the ozone being depleted?
Human activity, in particular since the industrial revolution, has caused an increase in ozone depleting compounds in the atmosphere, including CFCs and NOx .

Chlorofluorocarbons are compounds which are highly unreactive in the troposphere due to their very strong C-Cl and C-F bonds (polar bonds with high enthalpy). This makes them useful in things like: aerosols, refrigerant coolants, electrical circuit cleaning solvents etc.

However, it is because they are so unreactive that makes them so harmful!

The C-Cl bond has too high an enthalpy to be broken down in the troposphere, but when they reach the stratosphere, uv light can break this bond homolytically which produces chlorine radicals.

catalytic destruction of ozone

The chlorine radicals can then go on to catalyse the destruction of ozone (it is a homogeneous catalyst because it provides an alternative route for the reaction to take place and is regenerated). 

 It is estimated that one chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere by termination.
This means that more UV light is not absorbed by the thinner ozone layer and reaches earth.

Why is there a hole over the Antarctic?
Ozone is depleted over the antarctic in it's spring because sunlight falls on the polar stratospheric clouds (containinh chlorine radical reservoir compounds eg. HCl and ClONO₂.) which are formed and trapped in the cold air (-80'C) in the polar
vortex in the winter. When sunlight falls on these clouds, ozone destruction is able to 
happen, which forms a hole in the ozone during the spring.

Can the ozone ever recover?
Since the Montreal Protocol in 1987, many industrialized countries have fazed out the
use of ozone depleting compounds such as CFCs (apart from vital uses such as asthma
inhalers) and stratospheric chlorine levels have been continually dropping. Ozone can 
replenish itself however this takes time; moreover, it takes decades for CFC compounds
to be completely destroyed so it will take time before the ozone layer completely recovers.