Rising tensions with India and China over the European Union's "arrogant" law on carbon emissions could rob the region of the markets that can rescue it from economic malaise, airline leaders said on Thursday.

They also said they had prepared contingency plans for a possible exit of Greece from the euro, as part of the industry's extensive crisis management, and they were worried about a domino effect of more countries' being forced out of the currency bloc, with implications for all businesses.

The last three countries where polio is still paralysing children -- Afghanistan, Pakistan and Nigeria -- said on Thursday that they have enlisted Muslim women and religious leaders to allay fears of vaccination and wipe out the disease.

Polio cases are at an all-time low worldwide, following its eradication in India last year, raising hopes but also fears about a threat of resurgence especially in sub-Saharan Africa unless remaining reservoirs of polio virus are stamped out.

New Zealand's second largest city Christchurch was shaken by a magnitude 5.2 earthquake on Friday, but there were no immediate reports of damage or casualties.

The government seismology agency said the quake was centred 10 kilometres east of the city at a depth of 11 kilometres.

The city was devastated by a force 6.3 quake in February last year, killing nearly 200 people, and destroying the central business district and making large areas of surrounding suburbs uninhabitable.

China's central government plans to spend 170 billion yuan ($27 billion) this year to promote energy conservation, emission reductions and renewable energy, the Ministry of Finance said in a statement on its website on Thursday.

The ministry said China plans to promote more use of energy-saving products and low or no-emission power generation such as solar and wind. It also wants to accelerate the development of renewable energy, as well as energy-saving technologies, such as electric and hybrid cars.

Nearly three-quarters of Japanese companies support abandoning nuclear power after last year's Fukushima disaster, although a majority set the condition that alternative energy resources must be secured, a Reuters poll showed on Friday.

The poll offers fresh evidence of the deep public distrust of nuclear power, the role of which the government is reconsidering after the March 2011 earthquake and tsunami that wrecked the Fukushima nuclear plant, triggering a radiation crisis that caused mass evacuations and widespread contamination.

Map of timber value in the Amazon. Click for larger image and detailed caption provided by authors. Illustration: Sadia Ahmed and Robert Ewers, Imperial College London

Researchers exploring the value of different types of timber across the Amazon rainforest have produced a fascinating choropleth map to illustrate their findings.

Shown above, it consists of timber values plotted on a gridded map of equal-area cells, each 0.25km-squared in size. Click on the image to view the full-size version.

Record growth over the last year pushed the UK green goods and services market past the £122bn mark, according to new government figures that reveal the low carbon economy now employs almost one million people.

The sector grew 4.7 per cent against the 2009/10 figure of £116.8bn, providing an additional £5.4bn of economic activity as green industries continued to defy the sluggish progress made by the rest of the economy.

Even as drought persists in parts of Kenya's arid north, intense rains are claiming lives in other parts of the country – flooding slums in the capital Nairobi, sweeping away hikers in the Rift Valley, and destroying crops.

Many Kenyans shake their heads in dismay at the increasingly extreme and volatile weather, which is costing money as well as lives in east Africa's economic powerhouse.

The captain and the navigation officer of a container ship that smashed into a reef off a popular New Zealand holiday resort were jailed on Friday for causing the country's worst environmental disaster in decades.

The two men, captain Mauro Balomaga and navigation officer Leonil Relon, both Filipino nationals, were jailed for seven months. They had faced maximum terms of seven years imprisonment.

The United Nations chief, Ban Ki-moon, held out little hope on Thursday of an historic outcome at the Rio global development summit, now less than a month away, admitting negotiations had been "painfully slow".

The warning was the latest from United Nations officials and others involved in preparations that the summit, known as Rio+20, is unlikely to replicate the breakthrough achievements of the original environmental gathering in the city in 1992.