Dispatches

Cities are just another ecosystem to Hugh Aldridge, a former ecologist who wants to track their resource use and waste generation in real time. “The great dream of all ecologists is to measure everything going on in a complex system”, he says. “It offers potential not only to woodlands and streams but also to cities.” Integrating data from municipal systems will boost efficiency, making cities greener as well as able to accommodate more people sustainably as the world's population grows. Now, Aldridge is about to realize his dream. He manages intelligent infrastructure – think cheap, self-powering sensors that transmit data wirelessly to open-access websites – at the Center for Information Technology Research in the Interest of Society (CITRIS; University of California, Berkeley), a research center that San Francisco chose in March 2013 to launch its transition to a “smart city”. San Francisco is partnering with Paris, which is working with Inria, a European counterpart to CITRIS. Climatic and structural differences between San Francisco and Paris will make the smart city projects applicable to more parts of the world. “Paris is relatively colder, so houses there use more heating”, Aldridge continues, adding, “It also has lots of tiny streets, where tall buildings could make ‘traffic canyons’ that trap ozone”. Ultimately, he'd also like to include cities in other climatic zones, such as the high tropics. Initial projects include sensor networks that measure the energy use of individual buildings, transportation patterns, and street-by-street levels of CO2 and ozone. “Greenhouse gases are a great barometer of sustainability”, remarks Guillermo Rodriguez, a San Francisco Department of the Environment spokesman. “They're easy to track and are linked to everything, from traffic to energy to air quality to green buildings.” In addition, the gases from each source have a distinctive fingerprint, which will help cities manage emissions. “You'll know exactly where the emissions came from, and when, and you'll know the emitter by the gas signature”, Aldridge explains. Becoming a smart city should also yield economic benefits. “Sending data on energy use to an open source means the private sector can offer solutions to decreasing your bills”, Rodriguez says. Besides saving people money, this would create business opportunities and jobs. Encouraging these new companies is also key to making smart cities work. As Aldridge points out, “We can do the research but we need [the businesses] to do the implementation and large-scale projects.” Monitoring systems from energy to transportation will make cities greener. In late March, the Brazilian Association of Supermarkets (ABRAS) announced that its members will no longer sell beef linked to deforestation in their stores. The pledge promises to take a bite out of beef production, which is responsible for 60–80% of deforestation in the Amazon rainforest. Tropical deforestation generates roughly 20% of global greenhouse-gas (GHG) emissions. A kilogram of Brazilian beef raised on deforested Amazon pastures produces about 703 kg of GHGs, according to research by Sverker Molander, an environmental systems analyst at Chalmers University (Göteborg, Sweden). Most of the beef produced in the Amazon is consumed domestically, making the new pledge a potentially powerful tool. The decision settles a suit brought against ABRAS and its 2800 members by Brazil's Federal Public Ministry (MPF) in 2009. The 82 000 stores covered under the agreement will no longer sell beef harvested from areas illegally logged in the Amazon and will provide package labeling that identifies where the beef originated. The 2009 suit came on the heels of a Greenpeace campaign pressuring the three largest slaughterhouses in Brazil to avoid buying cattle from farms on deforested land, says Paulo Adario, forest strategist with Greenpeace International (Manaus, Brazil). Greenpeace targeted overseas companies that have become more environmentally conscious, such as McDonald's. “So the Brazilian companies realized that if they wanted to make money and export their goods, they had to be sensitive to environmental concerns”, explains Adario. The three slaughterhouses signed an agreement with Greenpeace in 2009 and are now working with their supply chains and using satellite-based data to ensure that their beef suppliers are not clearing forests. On April 5, The Nature Conservancy, Walmart Brazil, and Marfrig Group (a Brazilian food producer) launched a partnership to promote sustainable cattle production in the Amazon. The project includes outreach to farmers and a system for tracking beef from pasture to supermarket. The MPF says that its work with cattle ranchers has decreased the rate of deforestation in the state of Para by 60% since 2009. “If the big companies compete for business on the basis of the environment, it will change things”, Molander concludes. Over the past century, invasive cheat-grass (Bromus tectorum) has transformed the sagebrush landscape of the western US into highly fire-prone grasslands. But a native soil bacterium may turn the tables on cheatgrass, according to new research conducted by scientists with the US Department of Agriculture's Agricultural Research Service (ARS). Cheatgrass develops early in the spring, monopolizing precious soil moisture, then dries up and serves to fuel the fires that once occurred every 60–110 years but now arise on average every 5 years. Native perennial grasses and shrubs can't re-establish and the animals that depend on them are in decline. “We were investigating soil microbes that inhibit food crops and wondered if we could find native bacteria that inhibit [the growth of] weeds”, explains Ann Kennedy, a soil scientist with the ARS (Pullman, WA). Kennedy isolated 15 000 different types of bacteria from soil samples and selected potential candidates that suppressed cheatgrass but had no effect on crops or native plants, weren't pathogenic, and were unlikely to become invasive. The most promising was a special strain of Pseudomonas fluorescens. Tests on 10-acre test plots 5 years after a single application of the bacteria show that cheatgrass populations are nearly eradicated. Kennedy is quick to point out, however, that “it's not a silver bullet – you still have to combine it with other management tools, such as controlled grazing and herbicides”. P fluorescens lives on root surfaces and produces a mixture of proteins and sugars that prevent cheatgrass root cells from elongating; without a massive root system, the stunted plants are unable to flower and set seed. “After 3 years, we don't see high numbers of the bacteria but native plants increase in abundance and become more competitive”, Kennedy continues. “The bacterium is a breakthrough because it's a native organism that combats an invasive species but then its levels go back down”, says Cynthia Brown, a plant invasion ecologist at Colorado State University (Fort Collins). The US Fish and Wildlife Service is supporting Environmental Protection Agency registration of the bacteria as a biopesticide this summer, and Kennedy's team will conduct large-scale trials in the fall. Australia – one of the world's largest per-capita greenhouse-gas polluters –appears to have finally turned the corner, with carbon emissions beginning to fall in the face of declining electricity demand and the introduction last July of a carbon tax (AU$23 or US$24 per metric ton of CO2 equivalent [tCO2eq]) on the largest industry emitters. Total emissions fell by 2 million tCO2eq between September and December 2012, according to the latest Carbon Emissions Index published by energy consultants Pitt& Sherry (Canberra). The Index found that a 12% decline in electricity emissions since 2009 had more than offset strong growth in emissions from petroleum-based fuels. In the last half of 2012 alone, after the carbon tax was introduced, electricity emissions dropped 8.6%, or 7.5 million tCO2eq. The electricity emissions trend is linked to a steady downturn in consumer demand, steep rises in power prices, and increased reliance on hydroelectric and natural gas generation, which are lessening Australia's traditional dependence on coal. “Probably for the first time in Australian history, we're seeing coal-fired power operators shutting down some of their turbines”, says Tony Mohr (Australian Conservation Foundation, Melbourne). “In the past, they have always had new power stations on the drawing board, or have run their existing stations at maximum capacity. So we are seeing a ‘fork in the road’ moment for the coal-fired power industry, and that's great news.” Australia's energy tax is encouraging a move to renewable energy sources. The Australian Government claims that the trends show that the controversial carbon tax is working, in the lead-up to the planned national Emissions Trading Scheme linked to the European market in 2015. But Mohr warned that the declining electricity emissions were masking growth from other sources, particularly fugitive emissions associated with Australia's booming mining exports industry. And he says Australia has its work cut out to meet its Kyoto second commitment (K2) target to reduce emissions to 5% below 2000 levels by 2020, particularly if the carbon tax is repealed following a change in government when national elections are held in September. “Australia's K1 target of 108% of 1990 levels was so lenient”, explains Mohr. “We were one of only two countries with an increased emissions target, and we hit it without even trying, just by slowing down land clearing. So the growth in emissions across the rest of the economy was hidden by this one-off benefit. But reaching the K2 target is going to take a concerted effort, and we won't get there with only incentive programs and no carbon tax.” Sharks, rays, and skates have swum the world's oceans for 400 million years, but over recent decades the global fishing boom, combined with the relatively slow growth and reproductive rates of these fish, has caused substantial population declines in numerous species. The plight of many shark species – whose fins can fetch US$700 per pound in Asian markets – is especially grim. A recent, comprehensive study (Mar Policy 2013; doi:10.1016/j.marpol.2012.12.034) concludes that about one out of every 15 sharks is killed by fisheries annually. Fisheries ecologist Boris Worm (Dalhousie University, Halifax, Canada) and colleagues used a wide range of published reports and modeling techniques to assess shark populations and estimate global catches, average levels of mortality, and potential extinction risks. The results indicated that ~100 million sharks (1.44 million metric tons) perished in fisheries in 2000. Despite recent bans on shark finning by several nations, estimates for 2010 were comparable: 97 million (1.41 million metric tons) killed. “Existing shark-finning bans often aren't well enforced and don't necessarily reduce mortality”, Worm explains. “Such bans simply ensure that the rest of the shark is landed and used.” The fins of hammerhead and other sharks are in great demand for Asian cuisine. These estimates are based on very conservative assumptions, Worm notes. “Given the high uncertainty associated with the numbers of sharks caught and then discarded, the actual figure could be in excess of 100 million – possibly as high as 273 million.” The 100-million estimate implies that 6.7% of shark populations are killed by fishing activity every year; calculating losses directly from available fisheries data yields a similar figure of 6.4%. Working with statistics from the global trade in fins, the authors arrived at a figure of 7.9%. As Worm points out, all of these rates considerably exceed the limits for maintaining many shark populations. Because sharks are important predators, the consequences for marine ecosystems could be substantial. The overfishing of sharks needs to be reduced drastically to rebuild depleted populations, the researchers warn. One positive step was taken at the March meeting of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in Bangkok, Thailand, when representatives of 178 nations voted to protect five of the most vulnerable shark species and two species of manta rays. The ruling requires that CITES permits be obtained for trading in these species and that evidence demonstrating that they were harvested legally and sustainably be provided. Says Worm, “I very much welcome this decision; it is a sound policy based on sound science”. In most cities in India, municipal solid waste is discarded in low-lying, unlined landfills from which large volumes of landfill gas (LFG) are emitted, including methane, an especially potent greenhouse gas (GHG). But a pilot demonstration project at New Delhi's Okhla landfill site has shown that LFG can be captured, purified, and used as a source of energy. The LFG collection system is composed of a series of vertical wells for extracting the gas, a scrubber that removes hydrogen sulfide from the gas, and a moisture removal unit. The gas is then conditioned and treated prior to its use as an energy source. If scaled up, LFG produced at Okhla could provide cooking fuel to 18 000 households and electricity to adjacent large institutional users. Methane is produced in landfills when organic waste is decomposed by bacteria under anaerobic conditions. Due to rapid decomposition rates, big landfill sites can produce large amounts of methane over extended periods of time. LFG from smaller sites can be captured and supplied directly to industrial units in the vicinity, for use in boilers or other equipment. Waste-related GHG emissions have been reduced in developed countries, either by capturing LFG or by diverting organic waste away from landfills. “The scenario is different in developing countries, where dumping of waste in landfills is the least-cost disposal option available to municipal bodies. Capturing and using LFG can therefore be a great GHG reduction strategy”, explains Rajendra Kumar Pachauri (Director General, The Energy and Resources Institute [TERI], New Delhi). Current procedures for municipal solid waste disposal have often attracted criticism. “Government agencies are deploying outdated incinerator technology to burn waste, which is only going to worsen the problem due to emission of harmful gases”, contends Gopal Krishna (ToxicsWatch Alliance, New Delhi). Innovative technologies such as LFG capture could provide sustainable alternatives. The Okhla project is being operated jointly by TERI and Jamia Millia Islamia University. GAIL (India) Limited, the country's largest state-owned natural gas processor, has reached an understanding with the municipal government of the city for implementation of the LFG collection process at a second site, Ghazipur, a landfill in the eastern part of the city. Recently, researchers from the University of Notre Dame's Environmental Change Initiative (ECI) applied new techniques to help detect and prevent aquatic invasive species from entering US waters (Conserv Lett 2013; doi:10.1111/conl.12017). Once established, such species cause massive ecological and economic damage to fisheries and other industries each year. “This research combines two emerging but proven technologies – environmental DNA (eDNA) and Light Transmission Spectroscopy (LTS) – to address the growing problem of aquatic invasive species by increasing our ability to detect dangerous species before they arrive or when they are still rare in the environment and have not yet caused substantial damage”, says lead author Scott Egan (ECI, Notre Dame, IN). These new methods will improve the monitoring of ships' ballast waters, which often harbor stowaway organisms. In the Great Lakes alone, approximately 180 non-indigenous species have become established since European settlement, with about 70% arriving in water discharged from the ballast tanks of transoceanic ships. eDNA is a species surveillance tool that examines DNA found in microscopic bits of tissue of various aquatic species (eg pieces of fish scales and insect exoskeletons) suspended in the water. LTS can detect changes in the size of small particles as they come into contact with the DNA of specific target species, even if those species are relatively scarce in the water samples. Given the importance of ballast-water monitoring, this work “implies that eDNA sampling and LTS could enable rapid species detection in the field in the context of research, voluntary or regulatory surveillance, and management actions to lower the risk of the introduction or spread of harmful species”, attests Egan. For the future, Egan and his ECI colleagues are working to improve the sensitivity of LTS for even lower concentrations of target species and to expand the number of species these techniques are able to detect. They are also developing a species detection platform that uses all of these tools in the field, on large ships or at points of entry to the US. As Egan explains, “Future research applications will expand analyses to include threatened or endangered species, pest species of agricultural concern, infectious species of health concern (eg pathogens and parasites), and species that pose biosecurity risks”. Environmental groups have been angered by a new US Environmental Protection Agency (EPA) permit designed (in part) to regulate ballast-water discharge from commercial ships in US waters, a permit, they insist, that misses the mark for preventing the spread of invasive species. The National Pollutant Discharge Elimination System Vessel General Permit (VGP) for Discharges Incidental to the Normal Operation of Vessels – released March 28 and that takes effect on December 19, 2013 – is the response to a lawsuit brought by plaintiff Northwest Environmental Advocates et al. Courts ruled in 2005 and 2008 that the EPA exceeded its authority under the US Clean Water Act by excluding from regulation those ballast discharges “incidental to normal vessel operations”. Such discharges have been largely responsible for invasive species reaching US waters. Problems are particularly noticeable in the Great Lakes system, where foreign invaders such as zebra mussels (Dreissena polymorpha), quagga mussels (Dreissena rostriformis bugensis), spiny water fleas (Bythotrephes longimanus), and round gobies (Neogobius melanostomus) have made their homes. The economic cost associated with this collective invasion of these lakes has been at up to every 5 years. a for The new permit includes ballast-water discharge for the first time. Vessels now ensure that than than (in their are discharged per of ballast water. every of that water than between and in that the is because of a that the Great and because there is no for at every says of National Resources according to for Water “The EPA to the water quality and of the waters and of the US the The permit environmental for the Great which have from invasive species, and for vessel and this of Government and on in an to the native The will in early to the of the plant species will come back but like could take says of the Nature which in with government from the and on the to 100 years for food and to help the Government with the after he first about the in 2009. “I that a new to the would be to use the traditional he explains. to and the 000 removal killed and another which were then The harvested from the animals was to the and to operators and according to for the Nature A and on at the of the The at for a including the and A removal project – on – is also to with and of Fisheries for the Government of and says government see of plant in areas where the first were in that be able to turn back the and the to it used to On March scientists the that make a for species from to researchers to an from bits of can then either a or an to create for would then be in a The by the National Society and a The Foundation, as a new tool for but such will numerous ecological a ecologist at University was one of the ecologists who at the by of that is now a been by the of and tools that could be developed to help populations on the of also is going to and it would be to be part of the to ensure that it is offers a of following often says. not at the meeting – including an ecologist at the University of – have is by the of ecologists and agencies in the concern is where to species, that target areas would to ensure and “If the is to species back in their former we need ecologists who those as well as the predators, and is another all for as but not as a says Hugh an ecologist at the University of whose tools to set “Given that is to be at in the it's to it would be than saving species in he points the has a “The for is when it's not being

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