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  • Seasonal wetlands face uncertain future

    Ephemeral wetland (Image: Tatenda Dalu)Image copyrightT.DALUImage captionEphemeral wetlands provide a variety of ecological services to a wide range of flora and fauna

    Seasonal wetlands - ecologically important habitats that become visible during rainy seasons - are facing an uncertain future, warn scientists.

    These ephemeral ecosystems support unique flora and fauna species that do not occur in permanent wetlands.

    Yet these poorly understood habitats are being lost to future generations as a result of poor land-use practices, the authors observed.

    The details have been published in the Global Change Biology journal.

    Although these intermittent, shallow-water seasonal natural features are most closely associated with arid or semi-arid landscapes, they are more widespread than generally realised.

    For example, more than half of the total river length in the US, Greece and South Africa is made up by sections that have temporary flow.

    Changing landscape

    "They tend to occur during the rainy season which is when you will see shallow water but for most months of the year, it will appear to be dry," explained co-author Tatenda Dalu, from Rhodes University, South Africa.

    The seasonal wetlands are dominated by aquatic biodiversity, he told BBC News.

    "You have your plankton, you have your insects, which then brings in the birds to feed on these insects," Dr Dalu said.

    "Some of these systems have unique communities of fish, such as the 'lung fish'."

    However, these unique ecosystems were vulnerable for a number of reasons, explained Dr Dalu.

    "The biggest threat we are seeing at the moment is either the digging up of the ecosystems or making them permanent.

    "By making them permanent, people accidently introduce invasive species which then wipe out the unique invertebrate communities."

    For example, people look to have a lake full of fish on their land. Very often, the introduced species of fish results in the unique habitat that had previously thrived in the intermittent water being squeezed to the point of becoming locally extinct.

    The team also recognised that changes to the climate system were set to alter rainfall and temperature patterns.

    The researchers observed in their paper: "In tropical regions of southern Africa, for example, drought is projected to be particularly problematic.

    "In such areas, ephemeral wetlands are highly likely to be affected given that ephemeral aquatic environments are internally drained systems, wholly reliant on localised rainfall."

    Enriching features

    Dr Dalu said the time to act to attempt to make the wetlands more resilient was now.

    "One of the most important things for us is to try to map as many of the systems as we can.

    "Having a record of where these unique systems exist will be important for the development of any further legislation."

    He said that the flora of ephemeral wetlands enriched people's lives, even if they were not aware of the ecological importance of such sites.

    "People will tell you about some of the unique flowers they see there," he said.

    "That's how people identify them but they do not know anything else about these seasonal wetlands."

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  • Heathrow third runway 'to breach climate change laws'

    Heathrow AirportImage copyrightPA

    Plans to expand Heathrow Airport are set to breach the government’s climate change laws, advisers have warned.

    The Committee on Climate Change says the business plan for Heathrow projects a 15% increase in aviation emissions by 2050.

    If that increase is allowed, members say, ministers will have to squeeze even deeper emissions cuts from other sectors of the economy.

    The government said it was determined to keep to its climate change targets.

    The Committee on Climate Change is a statutory body set up to advise the UK government on emissions targets.

    It warns that creating the space for aviation emissions to grow will impose unbearable extra emissions reductions on sectors like steel-making, motoring and home heating.

    The committee also says that in making the decision to allow a third runway at Heathrow, ministers appear to have jettisoned their policy that aviation emissions in 2050 would be frozen at 2005 levels.

    'Limited confidence'

    Its chair, Lord Deben, wrote to the Business and Energy Secretary Greg Clark, saying: “If emissions from aviation are now anticipated to be higher than 2005, then all other sectors would have to prepare for correspondingly higher emissions reductions.

    “Aviation emissions at 2005 levels already imply an 85% reduction in other sectors. My committee has limited confidence about the options (for achieving the compensatory cuts needed).”

    Already since 1990, aviation emissions have doubled while economy-wide emissions have reduced by more than a third. Ministers see aviation as a special case because low-carbon technology for planes is not well advanced.

    The committee says the Department for Transport appears to be planning to solve the aviation overshoot by buying permits to pollute from poor countries which have low levels of CO2 emissions.

    'Bear the costs'

    This is permitted internationally under a new code recently agreed by the aviation industry.

    But it is a departure from the government’s own existing policy - and rules stipulate that the change should have been checked with the committee before being agreed.

    A committee spokesman told BBC News: “The committee has consistently said the government should not plan to use credits to meet the 2050 target because these credits may not be available in the future and they may not be cheap.”

    Doug Parr from Greenpeace said the affair showed climate change was still an afterthought from a government pursuing business as usual.

    He said: “What ministers know full well but don't want to admit is that a third runway means other sectors of the economy will have to bear the costs of further carbon cuts - whether it’s regional airports or the manufacturing and steel industries.

    Thermal image showing heat loss from a houseImage copyrightSCIENCE PHOTO LIBRARYImage captionThe UK's leaky housing stock is a big challenge

    “If that's the plan, it's time ministers came clean about it with those concerned and the British public."

    A spokesman for the Department for Business, Energy and Industrial Strategy told BBC News: "The government agrees with the Airports Commission's assessment that a new runway at Heathrow can be delivered within the UK's carbon obligations.

    "We are considering how we will continue to reduce our emissions across the economy through the 2020s and will set this out in our emissions reduction plan, which will send an important signal to the markets, businesses and investors.

    "Our commitment to meeting our Climate Change Act target of an at least 80% emissions reduction below 1990 levels by 2050 is as strong as ever."

    But it’s not just on aviation that climate policies are struggling. The government’s long-awaited master plan for reducing long-term emissions has been delayed again - until early 2017.

    The government did signal help for electric vehicles in the Autumn Statement, although critics say it has much more to do.

    But the biggest challenge is the UK’s leaky housing stock: since the government scrapped its ill-fated Green Deal programme of home insulation it has had no nationwide plan to improve comfort and reduce emissions from existing homes.

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  • Bumper load of new viruses identified

    VirosphereImage copyrightUNIVERSITY OF SYDNEYImage captionViruses have been infecting invertebrates for possibly billions of years

    An international research team led from Australia and China has discovered nearly 1,500 new viruses.

    The scientists looked for evidence of virus infection in a group of animals called invertebrates, which includes insects and spiders.

    Not only does the study expand the catalogue of known viruses, it also indicates they have existed for billions of years.

    The findings were published in the journal Nature.

    Few would argue that all living species on Earth are susceptible to viruses – these microscopic parasites are ubiquitous.

    But virologists have long suspected that our current view of the diversity of viruses is blinkered – all too often constrained to those causing disease in humans, animals and plants, or to those that we can grow in the laboratory.

    A trip to a tropical rainforest or the African savannah gives a snapshot into the incredible diversity of visible life on Earth, but understanding the potentially mind-boggling myriad of minuscule viruses has not been so easy.

    Capturing new viruses is not like netting a new species of butterfly – viruses are invisible.

    Undeterred by this practical problem an international team was keen to survey invertebrates for new viral species.

    Invertebrates are spineless creatures and the group includes many familiar animals, such as insects, spiders, worms and snails. They represent the vast majority of animal species in the world today.

    Scientists wanting to work out the totality of viral "life" – although many virologists would argue that viruses are not truly alive – are starting to adopt techniques that reveal their genetic calling cards, revealed in the things they infect.

    MosquitoesImage copyrightAPImage captionSome invertebrates do carry viruses that can infect humans, but the newly identified ones probably pose very little risk

    Just like powerful new telescopes are peering deeper into space, revealing a wealth of hitherto unknown stars, next-generation sequencing techniques are providing new insight into the magnitude of the invisible world of viruses; a world we call the virosphere.

    We are familiar with DNA, the "stuff of life" that makes up the blueprint of our genomes. But many viruses use a different chemical to construct their genomes – a substance known as RNA.

    Just like DNA, this consists of strings of individual building blocks, or bases; each designated by a different letter: A, C, G and U.

    Next generation sequencing allows researchers to quickly determine the sequence of these letters. And if you work out the order of the letters on any chain of RNA, you can determine if it belongs to a virus and whether or not the virus is new.

    Its potential for virus discovery is huge.

    Dengue virus particlesImage copyrightSPLImage captionA minuscule universe: A highly magnified view of dengue virus particles

    The research team collected around 220 species of land- and water-dwelling invertebrates living in China, extracted their RNA and, using next-generation sequencing, deciphered the sequence of a staggering 6 trillion letters present in the invertebrate RNA "libraries".

    When the researchers analysed this mass of data they realised that they had discovered almost 1,500 new virus species – a whopping number by any measure. Many of these were so distinct that they did not easily fit into our existing virus family tree.

    Prof Elodie Ghedin from New York University, who was not directly involved with the study, told the BBC: "This is an extraordinary study providing the largest virus discovery to date.

    "It will no doubt remodel our view of the virus world and redraw virus phylogeny.

    "This is what happens when you combine a bold and brute force approach with the right technology and the right set of eyes."

    Even though some invertebrates carry viruses that can infect humans - like zika and dengue - the study authors do not think that these newly discovered viruses pose a significant risk.

    However, this cannot be ruled out entirely, and Prof Ghedin thinks that this is an important issue to address.

    "If we have learned anything from these types of true discovery projects is that when we start looking into places we haven’t looked at before, we find an incredible richness that goes beyond what was suspected.

    "It also makes a strong case for expanding virus surveillance to invertebrates in our quest to better understand (and predict) emerging viruses," she said.

    'Looking back'

    The research also showed that throughout time viruses have been trading genetic material to create new species – an incredible feat according to Prof Eric Delwart from the University of California, San Francisco, who told the BBC: "It shows a lego-like ability of different viral functional units to be recombined to create new viruses even when they originate from highly divergent viruses. The plasticity of viral genomes continues to amaze."

    Not only have these studies expanded our view of the diversity of viruses, they have also provided a more complete picture of virus history, as Prof Edward Holmes from the University of Sydney, who was involved in the study explained: "We have discovered that most groups of viruses that infect vertebrates – including humans, such as those that cause well-known diseases like influenza – are in fact derived from those present in invertebrates."

    He also believes that his group's data shows that viruses have been infecting invertebrates for possibly billions of years, raising the prospect that invertebrates are the true hosts for many types of virus.

    The researchers hope that next-generation sequencing can pave the way for virus discovery in a variety of other species. And it does not stop there.

    Prof Delwart thinks that further analyses of existing next-generation datasets may yield additional virus species unlike any that we have seen before.

    If future studies reveal anywhere near this number of new viruses, then we’ve only just scratched the surface. It seems that the virosphere is set to explode.

    Jonathan Ball is a professor of virology at Nottingham University. This coming Saturday, he will be taking part in CrowdScience, the new BBC World Service science weekly, which starts with a question from listener Ian in Jordan which is "where did viruses come from?"

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  • Europe's science ministers to decide on ExoMars rover

    ExoMars artist's impressionImage captionArtist's impression: The robot rover will aim to drill below Mars' surface

    European research ministers will be asked for a little over €400m (£345m; $430m) to put a rover on Mars in 2021 when they meet next week.

    This is the additional sum needed to finish building the European Space Agency's much-delayed ExoMars robot.

    A technical review has just concluded that the project is running true to its latest schedule, but it can only go forward with full funding.

    Ministers will decide ExoMars' fate at a council in Lucerne, Switzerland.

    The British-assembled rover would launch on a Russian rocket in August 2020 and land on the Red Planet eight months later.

    It is being designed with the ability to drill up to 2m below Mars' dusty terrain to look for evidence of microbial activity.

    Dr David Parker is Esa's director of Human Spaceflight and Robotic Exploration. He said member-state delegations to the agency had been expressing strong support for the project in the run-up to the Lucerne gathering.

    "The rover remains scientifically compelling because there is no other mission planned to go below the surface of Mars which is damaged by radiation and which would destroy any past or present life," he told BBC News.

    Jo JohnsonImage copyrightUKSAImage captionUK science minister Jo Johnson will be at the centre of the negotiations in Lucerne

    The six-wheeled robot is the second mission in a two-step venture that Europe is conducting with the Russians.

    The first phase has just seen a satellite to study Mars' atmosphere go into orbit around the planet, and a disc-shaped probe called Schiaparelli try to make a demonstration landing on its surface.

    Schiaparelli crashed but engineers say they learned important lessons that can now be applied to the rover's touch-down bid in four years' time.

    But to be in such a position, the six-wheeled vehicle will need the nod of ministers in Lucerne.

    Ahead of this council, Esa and its Russian counterpart, Roscosmos, have conducted a thorough review of the project's technical status, to establish that all the mission's hardware can be made ready in time.

    It was fears that some elements would be late that saw the mission slip earlier this year from its intended 2018 launch.

    The required equipment goes beyond just the rover and a suite of scientific instruments. It includes also a "cruise ship" to carry the vehicle to Mars (this will come from Germany) and the mechanism to land the robot on the surface (a major Russian contribution).

    "There has been intense technical work by the project members, including the industrial team led by Lavochkin (Russia) and Thales Alenia Space (Italy), which has now established an adequate schedule margin for launch at the overall system level and within the pieces of the system; so, the rover and the carrier, and so on," explained Dr Parker.

    Artist's impression of TGO and SchiaparelliImage copyrightESAImage captionArtwork: A satellite and demonstration lander arrived at Mars last month. The lander crashed

    It has been recommended that in order to shorten the timeline on what had previously been proposed, all the different elements will now be sent to an experienced facility in Toulouse, France, for final integration and testing - and only afterwards go to the launch site at Baikonur in Kazakhstan.

    Originally, final integration and testing was to be done at the spaceport.

    It is on the basis of the positive status report delivered this week to member state delegations that the funding request will now go forward to ministers.

    The little over €400m includes more than €300m for industry with the rest to cover Esa's internal costs.

    These include preparing the mission control centre that will command the rover on the surface of Mars.

    'Dumbed-down' rover

    But additional to all this money, member states will have to provide at some future point the funds to support the surface operation of the vehicle - assuming it gets down safely.

    The expectation is that the robot will explore the Red Planet for at least 218 Martian days; hopefully much longer.

    The two leading Esa countries in the ExoMars rover project are Italy and the UK. Both have indicated they will be offering substantial financial support at the Lucerne meeting.

    But it will require others in the 22-nation organisation to dig deep as well.

    3D modelImage captionAutonomous navigation would enable the rover to do more science

    Ministers will be discussing a great swathe of programmes in Switzerland, including continued participation in the space station and the development of future Earth observation satellites.

    For some nations, these alternative projects will be more important to them. Full commitment to ExoMars is not guaranteed, therefore.

    And even if all the funds are forthcoming, some issues of contention will no doubt persist.

    For example, there is currently an ongoing argument centred around the rover's use of autonomous navigation - the ability of the vehicle itself to plot the best path across the surface of Mars once instructed to go to a particular location.

    This feature - a UK development - was long considered an integral part of the mission, but has now been removed from the current design on the grounds of cost.

    Researchers though are likely to continue to press for its reinstatement because a robot that drives quickly and efficiently can do much more science in the time available - never mind the clear industrial spin-out potential from such technology.

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  • UN: Farming needs to harvest chance to cut emissions

    Combine-harvester working in a wheat field (image: AP)I

    The global farming sector has a big role to play in the effort to curb greenhouse gas emissions and adapting to future climate change, the UN says.

    A report by the Food and Agriculture Organization said agriculture accounted for about a fifth of emissions, which it said needed to be reduced.

    The State of Food & Agriculture 2016 report said "business as usual" would leave millions at risk from hunger.

    Last year, nations adopted a UN goal of ending hunger by 2030.

    "The climate is changing, so agriculture must change too," explained Rob Voss, director of FAO's Agricultural Development Economics division.

    "We are saying that because agriculture is already very affected by the impacts of climate change, particularly the countries in the tropical zones.

    "Also, agriculture is contributing itself to about one fifth of the global emissions of carbon dioxide and other greenhouse gases," Mr Voss, who headed the team that produced the FAO State of Food & Agriculture 2016 report, added.

    "If we continue along the present pathways then we will not be able to [deliver] food security around the world and we will not be able to stabilise the climate."

    Major changes

    As a result, he told BBC News, there was a need for "major changes" to take place in the sector.

    "One of the challenges is agriculture itself. As soon as we shovel the ground then we are already releasing greenhouse gas emissions. Also, as it is so dependent on water and quality of land, any impact from the change in climate has a direct impact."

    Therefore, he said, the challenge was bearing these changes in mind and looking at ways to shift to a more sustainable footing.

    "A lot of the technologies that are available that allow us to do things differently do face a number of hurdles, especially when it comes to smallholder farmers in developing countries.'

    These include the cost of changing the way farmers produce their food; knowledge of shifting to the novel ways of farming; urbanisation; access to water.

    In terms of making the change to deliver a robust global food system, Mr Voss said the report highlighted four steps that could be taken:

    "First, put in the steps that would help farmers switch to more sustainable practices, such as more efficient use of fertilizers and using heat tolerant and drought resistant crop varieties."

    He added that management systems, such as agroforestry - which places forestry cultivation around farmlands, would also be beneficial as it helps farmers build in great resilience against the impacts of climate change.

    "Secondly, we need to work harder to increase the capacity of soils and forestry to sequestrate carbon. Deforestation and changes to land-use is one of the major sources of emissions from the sector.

    "A third area where we can immediately start work on is to reduce food losses and waste. We estimate that about one third of the food we produce gets lost in the post-harvest process or gets wasted at the consumer end.

    Rebalancing diets

    "The fourth area, which is more challenging, is to try and do something about people's diets. What we have been seeing around the world is a clear shift towards increasing demands for food products that put a lot more pressure on natural resources."

    The report observed: "Rebalancing diets towards less animal-sourced foods would make an important contribution in this direction, with probable co-benefits for human health."

    FAO director-general Jose Graziano da Silva said that the coming twelve months should be about "putting commitments into action", referring to the adoption of the UN Sustainable Development Goal of delivering "zero hunger" by 2030.

    He also observed that agriculture was set to be one of the main topics for discussion at the forthcoming UN climate summit in Morocco in November.

    "Climate change threatens all dimensions of food security," Mr Graziano da Silva warned.

    "It will expose both urban and rural poor to higher and more volatile food prices. It will also affect food availability by reducing the productivity of crops, livestock and fisheries."

    He stated: "Hunger, poverty and climate change need to be tackled together."

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  • The European bison (Bison bonasus) can weigh as much as a car

    Schiaparelli artworkImage copyrightESAImage captionArtwork: The retrorockets should have fired for about 30 seconds

    Europe's Schiaparelli lander did not behave as expected as it headed down to the surface of Mars on Wednesday.

    Telemetry data recovered from the probe during its descent indicates that its parachute was jettisoned too early.

    The rockets it was supposed to use to bring itself to a standstill just above the ground also appeared to fire for too short a time.

    The European Space Agency (Esa) has not yet conceded that the lander crashed but the mood is not positive.

    Experts will continue to analyse the data and they may also try to call out to Schiaparelli in the blind hope that it is actually sitting on the Red Planet intact.

    In addition, the Americans will use one of their satellites at Mars to image the targeted landing zone to see if they can detect any hardware. Although, the chances are slim because the probe is small.

    For the moment, all Esa has to work with is the relatively large volume of engineering data Schiaparelli managed to transmit back to the "mothership" that dropped it off at Mars - the Trace Gas Orbiter.

    This shows that everything was fine as the probe entered the atmosphere. Its heatshield appeared to do the job of slowing the craft, and the parachute opened as expected to further decelerate the robot.

    But it is at the end of the parachute phase that the data indicates unusual behaviour.

    "We cannot resolve yet under which, let's say, logic that the machine has decided to eject the parachute. But this is definitely far too early compared to our expectations," Andrea Accomazzo, the head of operations for Esa's planetary missions, told BBC News.

    Not only is the chute jettisoned earlier than called for in the predicted timeline, but the retrorockets that were due to switch on immediately afterwards are seen to fire for just three or four seconds. They were expected to fire for a good 30 seconds.

    In the downlinked telemetry, Schiaparelli then continues transmitting a radio signal for 19 seconds after the apparent thruster shutoff. The eventual loss of signal occurs 50 seconds before Schiaparelli was supposed to be on the surface.

    Many scientists here at mission control have taken all this information to mean one thing - that the probe crashed at high speed. It is likely it went into freefall a kilometre or two above the surface.

    Officially, though, Esa experts say they cannot at this stage fully interpret what happened until a velocity profile for the probe is properly reconstructed.

    Once that is done, a match can be made against known events and their predicted altitudes. It ought then to be possible to gauge with some confidence whether Schiaparelli did indeed hit the ground at a catastrophic speed.

    Landing on Mars is always a daunting prospect.

    It is necessarily a high-speed approach that has to be got just right or the spacecraft runs the risk of smashing into the ground.

    If the robot is later confirmed as lost, it will obviously be a major blow to Esa which suffered the disappointment of the Beagle-2 lander's failure at Mars in 2003.

    But officials here have tried to emphasise Schiaparelli's role as a technology demonstrator - a project to give Europe the learning experience and the confidence to go ahead with the landing on Mars in 2021 of an ambitious six-wheeled rover.

    This future vehicle is expected to use some of the same technology as Schiaparelli, including its doppler radar to sense the distance to the surface on descent, and its guidance, navigation and control algorithms.

    What will concern commentators is that the budget for the rover is not yet secure. It is short by about 300m euros. If Schiaparelli is indeed lost, Esa officials may find themselves having to work harder to explain to member states why the extra investment remains worthwhile.

    The agency's director-general, Jan Woerner, was bullish, however. The achievement of getting the TGO into a parking orbit at Mars to do several years of atmospheric study, combined with the retrieval of engineering data from Schiaparelli's descent, would, he said, play well with Europe's space ministers when they came to make decisions about the rover.

    "I think they will see that this mission is a success. We have the function that we need for the 2020 mission, and therefore I think we don't have to convince them - we just have to show them. The results are obvious," he told reporters.

     

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