Australia boasts over 500 national parks covering 28 million hectares of land, or about 3.6% of Australia. You could be forgiven for thinking we’re doing well in the biodiversity-conservation game.
But did you know that of those more than 500 national parks, only six are managed by the Commonwealth Government? For marine parks, it’s a little more: 61 of the 130-plus are managed primarily by the Commonwealth. This means that the majority of our important biodiversity refuges are managed exclusively by state and territory governments. In other words, our national parks aren’t “national” at all.
In a world of perfect governance, this wouldn’t matter. But we’re seeing the rapid “relaxation” of laws designed to protect our “national” and marine parks by many state governments. Would making all of them truly national do more to conserve biodiversity?
One silly decision resulting in a major ecosystem disturbance in a national park can take decades if not hundreds of years to heal. Ecosystems are complex interactions of millions of species that take a long time to evolve – they cannot be easily repaired once the damage is done.
It’s interesting when a semi-random tweet by a colleague ends up mobilising a small army of scientists to get pissed off enough to co-write an article. Euan Ritchie of Deakin University started it off, and quickly recruited me, Mick McCarthy, David Watson, Ian Lunt, Hugh Possingham, Bill Laurance and Emma Johnston to put together the article. It’s a hugely important topic, so I hope it generates a lot of discussion and finally, some bloody action to stop the rapid destruction of this country’s national parks system.
It’s make or break time for Australia’s national parks.
National parks on land and in the ocean are dying a death of a thousand cuts, in the form of bullets, hooks, hotels, logging concessions and grazing licences. It’s been an extraordinary last few months, with various governments in eastern states proposing new uses for these critically important areas.
Australia’s first “National Park”, established in 1879, was akin to a glorified country club. Now called the “Royal National Park” on the outskirts of Sydney, it was created as a recreational escape for Sydney-siders, with ornamental plantations, a zoo, race courses, artillery ranges, livestock paddocks, deer farms, logging leases and mines.
Australians since realised that national parks should focus on protecting the species and natural landscapes they contain. However, we are now in danger of regressing to the misguided ideals of the 19th Century.
We sent out this media release the other day, but it had pretty poor pick-up (are people sick of the carbon price wars?). Anyway, I thought it prudent to reprint here on CB.com.
Will Australia’s biodiversity benefit from the new carbon economy designed to reduce greenhouse gas emissions? Or will bio-’perversities’ win the day?
“Cautious optimism” was the conclusion of Professor Corey Bradshaw, Director of Ecological Modelling at the University of Adelaide’s Environment Institute. He is lead author of a new paper published in the journal of Biological Conservation which reviewed the likely consequences of a carbon economy on conservation of Australian biodiversity.
“In most circumstances these two very important goals for Australia’s future - greenhouse gas emissions reduction and biodiversity conservation – are not mutually exclusive and could even boost each other,” Professor Bradshaw says.
“There are, however, many potential negative biodiversity outcomes if land management is not done with biodiversity in mind from the outset.”
The paper was contributed to by 30 Australian scientists from different backgrounds. They reviewed six areas where Australia’s Carbon Farming Initiative could have the greatest impact on biodiversity: environmental plantings; policies and practices to deal with native regrowth; fire management; agricultural practices; and feral animal control.
“The largest biodiversity ‘bang for our buck’ is likely to come from tree plantings,” says Professor Bradshaw. “But there are some potential and frightening ‘bioperversities’ as well. For example, we need to be careful not to plant just the fastest-growing, simplest and non-native species only to ‘farm’ carbon.
“Carbon plantings will only have real biodiversity value if they comprise appropriate native tree species and provide suitable habitats and resources for valued fauna. Such plantings could however risk severely altering local hydrology and reducing water availability.”
Professor Bradshaw says carefully managing regrowth of once-cleared areas could also produce a large carbon-sequestration and biodiversity benefit simultaneously. And carbon price-based modifications to agriculture that would benefit biodiversity included reductions in tillage frequency, livestock densities and fertiliser use, and retention and regeneration of native shrubs. Read the rest of this entry »
Kakapo are unique among the ~ 400 parrot species (Psittaciformes) for being flightless, nocturnal and extremely long-lived (up to 100 years!). Additionally, they are herbivorous (seeds, fruits, polen, plants), males can weigh up to 2-4 kg (40% heavier than females), and females lay their eggs on the ground or cavities – i.e., 3 eggs in a single clutch annually, although 2 clutches might occur if the nest fails at the beginning of the reproductive season or if the eggs are taken for artificial incubation.Native to New Zealand, kakapo once inhabited the subalpine fringes of forest and scrub. Polynesians (1000 years ago) and Europeans (mostly in the XIX Century) arrived in the archipelago accompanied by dogs, cats, rats and mustelids that cornered kakapo populations in the Fiordland region (south-west of the South Island) where it was declared extinct in 1989. In 1977, a population of some 200 individuals was found on Stewart Island - this population was already in decline to the claws and jaws of feral cats. By the 1980s, the failure of captive breeding programs prompted the transfer of 60 individuals from Steward to carnivore-free islands. The global (known) population ‘rocketed’ from 50 individuals in 1999 to 126 in the 2012 censuses and, consequently, the kakapo’s IUCN status changed in 2000 from ‘Extinct in the Wild’ to ‘Critically Endangered’. Under the management of the Kakapo Recovery Programme, kakapo are now present on the islands of Codfish, Anchor and Little Barrier.
Inbreeding, system shocks caused by fire or cyclones (for example), or demographic stochasticity (by which two or more outcomes are possible) such as how many males and females will be born in a single year, are all factors that threaten the persistence of small and fragmented populations. They can, however, be reverted by conservation actions.
If you have ever taken dancing classes, you will be familiar with the scarcity of male partners and how this can jeopardize group learning. When reproduction, rather than salsa pirouettes, is at stake, a biased sex ratio can compromise the persistence of species. For instance, when females are unable to find males (or vice versa), fertility rates can collapse as a result – a well-known cause of an Allee effect (1). Curiously, natural selection can promote such bias by favouring a species’ investment in litters dominated by one of the two genders. The evolutionary formulation of such scenario is that females can adjust the sex ratio of their offspring depending on the amount of available resources (2) – see contrasting cross-taxa studies on this subject (3-5). Thus, when resources abound (e.g., food), mothers can afford the offspring’s gender requiring more resources to reach adulthood or once adulthood is reached, is less likely to reproduce successfully (6). This predisposition to one gender or another can be key to the conservation of endangered species (7).
The kakapo case
At the end of the 1990s, the New Zealand Department of Conservation placed dispensers of supplementary food in the territories of some kakapo (a rather enormous, flightless parrot Strigops habroptilus) to encourage their reproduction. Back then, only 60 individuals were left of the entire species . Unfortunately, those females with access to the supplemental food conceived 67% of male chicks (so exacerbating the fact that kakapo populations are naturally male-biased), while those females without extra feeding had 71% of female chicks (8). Something wasn’t working. Read the rest of this entry »
I’ve had a busy weekend entertaining visiting colleagues and participating in WOMADelaide‘s first-ever ‘The Planet Talks‘. If you haven’t heard of WOMADelaide, you’re truly missing out in one of the best music festivals going (and this is from a decidedly non-festival-going sort). Planet Talks this year was a bit of an experiment after the only partially successful Earth Station festival held last year (it was well-attended, but apparently wasn’t as financially successful as they had hoped). So this year they mixed a bit of science with a bit of music – hence ‘Planet Talks’. Paul Ehrlich was one of the star attractions, and I had the honour of going onstage with him yesterday to discuss a little bit about human population growth and sustainability. It was also great to see Robyn Williams again. All the Talks were packed out – indeed, I was surprised they were so popular, especially in the 39-degree heat. Rob Brookman, WOMADelaide’s founder and principal organiser, told me afterward that they’d definitely be doing it again.
But my post really isn’t about WOMADelaide or The Planet Talks (even though I got the bonus of meeting one of my favourite latin bands, Novalima, creators of one of my favourite songs). It’s instead about a paper I heralded last year that’s finally been accepted.
In early 2012 at the Terrestrial Ecosystem Research Network (TERN) symposium in Adelaide, the Australian Centre for Ecological Analysis and Synthesis (ACEAS) put on what they called the ‘Grand Challenges’ workshop. I really didn’t get the joke at the time, but apparently the ‘grand challenge’ was locking 30 scientists with completely different backgrounds in a room for two days to see if they could do anything other than argue and bullshit. Well, we rose to that challenge and produced something that I think is rather useful.
The paper is a rather in-depth review of how we, 30 fire, animal, plant, soil, landscape, agricultural and freshwater biologists, believe Australia’s new carbon-influenced economy (i.e., carbon price) will impact the country’s biodiversity. Read the rest of this entry »
But – and it’s a big ‘but’ – we have to be wary of claiming the end of the world as we know it or people will shut down and continue blindly with their growth and consumption obsession. We as scientists also have to be extremely careful not to pull concepts and numbers out of our bums without empirical support.
Specifically, I’m referring to the latest ‘craze’ in environmental science writing – the idea of ‘planetary tipping points‘ and the related ‘planetary boundaries‘. It’s really the stuff of Hollywood disaster blockbusters – the world suddenly shifts into a new ‘state’ where some major aspect of how the world functions does an immediate about-face. Read the rest of this entry »
One thing that has simultaneously amused, disheartened, angered and outraged me over the past decade or so is how anyone in their right mind could even suggest that scientists band together into some sort of conspiracy to dupe the masses. While this tired accusation is most commonly made about climate scientists, it applies across nearly every facet of the environmental sciences whenever someone doesn’t like what one of us says.
First, it is essential to recognise that we’re just not that organised. While I have yet to forget to wear my trousers to work (I’m inclined to think that it will happen eventually), I’m still far, far away from anything that could be described as ‘efficient’ and ‘organised’. I can barely keep it together as it is. Such is the life of the academic.
More importantly, the idea that a conspiracy could form among scientists ignores one of the most fundamental components of scientific progress – dissension. And hell, can we dissent!
Yes, the scientific approach is one where successive lines of evidence testing hypotheses are eventually amassed into a concept, then perhaps a rule of thumb. If the rule of thumb stands against the scrutiny of countless studies (i.e., ‘challenges’ in the form of poison-tipped, flaming literary arrows), then it might eventually become a ‘theory’. Some theories even make it to become the hallowed ‘law’, but that is very rare indeed. In the environmental sciences (I’m including ecology here), one could argue that there is no such thing as a ‘law’.
Well-informed non-scientists might understand, or at least, appreciate that process. But few people outside the sciences have even the remotest clue about what a real pack of bastards we can be to each other. Use any cliché or descriptor you want – it applies: dog-eat-dog, survival of the fittest, jugular-slicing ninjas, or brain-eating zombies in lab coats.
The saying “it isn’t rocket science” is a common cliché in English to state, rather sarcastically, that something isn’t that difficult (with the implication that the person complaining about it, well, shouldn’t). But I really think we should change the saying to “it isn’t ecology”, for ecology is perhaps one of the most complex disciplines in science (whereas rocket science is just ‘complicated’). One of our main goals is to predict how ecosystems will respond to change, yet what we’re trying to simplify when predicting is the interactions of millions of species and individuals, all responding to each other and to their outside environment. It becomes quickly evident that we’re dealing with a system of chaos. Rocket science is following recipes in comparison.
The prevailing wisdom is that big species have slower life history rates (reproduction, age at first breeding, growth, etc.), and so cannot replace themselves fast enough when the pace of their environment’s change is too high. Small, rapidly reproducing species, on the other hand, can compensate for higher mortality rates and hold on (better) through the disturbance. Read the rest of this entry »
Scientists Statement on the Roundtable on Sustainable Palm Oil’s Draft Revised Principles and Criteria for Public Consultation – November 2012
As leading scientists with prominent academic and research institutions around the world, we write to encourage the Roundtable on Sustainable Palm Oil (RSPO) to use this review of the RSPO Principles and Criteria as an opportunity to ensure that RSPO-certified sustainable palm oil is grown in a manner that protects tropical forests and the health of our planet. We applaud the RSPO for having strong social and environmental standards, but palm oil cannot be considered sustainable without also having greenhouse gas standards. Nor can it be considered sustainable if it drives species to extinction.
Tropical forests are critical ecosystems that must be conserved. They are home to millions of plant and animal species, are essential for local water-cycling, and store vast amounts of carbon. When they are cleared, biodiversity is lost and the carbon is released into the atmosphere as carbon dioxide, a greenhouse gas that drives climate change.
Moreover, tropical areas with peat soils store even larger amounts of carbon and when water is drained and the soils exposed, carbon is released into the atmosphere for several decades, driving climate changei. In addition, peat exposed to water in drainage canals may decay anaerobically, producing methane – a greenhouse more potent than carbon dioxide.
Palm oil production continues to increase in the tropics, and in some cases that production is directly driving tropical deforestation and the destruction of peatlandsii. Given the large carbon footprint and irreparable biodiversity loss such palm oil production cannot be considered sustainable. Read the rest of this entry »
Illegal logging is booming, as criminal organisations tighten their grip on this profitable global industry. Hence, it comes just in the nick of time that Australia, after years of debate, is on the verge of passing an anti-logging bill.
Illegal logging is an international scourge, and increasingly an organised criminal activity. It robs developing nations of vital revenues while promoting corruption and murder. It takes a terrible toll on the environment, promoting deforestation, loss of biodiversity and harmful carbon emissions at alarming rates.
Moreover, the flood of illegal timber makes it much harder for legitimate timber producers. The vast majority of those in Australia and New Zealand have difficulty competing in domestic and international markets. That’s one reason that many major Aussie retail chains and brands, such as Bunnings, Ikea-Australia, Timber Queensland, and Kimberly-Clark, are supporting the anti-illegal logging bill.
Illegal logging denies governments of developing nations revenue worldwide. Bill Laurance.
Illegal logging thrives because it’s lucrative. A new report by Interpol and the United Nations Environment Programme, “Green Carbon, Black Trade”, estimates the economic value of illegal logging and wood processing to range from $30 billion to $100 billion annually. That’s a whopping figure — constituting some 10-30% of the global trade in wood products.
Illegal logging plagues some of the world’s poorest peoples, many of whom live in tropical timber-producing countries. According to a 2011 study by the World Bank, two-thirds of the world’s top tropical timber-producing nations are losing at least half of their timber to illegal loggers. In some developing countries the figure approaches 90%.
Many nations export large quantities of timber or wood products into Australia. These include Indonesia, Papua New Guinea and the Solomon Islands, all of which are suffering heavily from illegal logging. Many Chinese-made wood and paper imports also come from illegal timber. Indonesian President Susilo Bambang Yudhoyono has been pleading with timber-importing nations like Australia to help it combat illegal logging, which costs the nation billions of dollars annually in lost revenues.
The new Interpol report shows just how devious illegal loggers are becoming. It details more than 30 different ways in which organised criminal gangs stiff governments of revenues and launder their ill-gotten gains.
The variety of tactics used is dizzying. These tactics include falsifying logging permits and using bribery to obtain illegal logging permits, logging outside of timber concessions, hacking government websites to forge transportation permits, and laundering illegal timber by mixing it in with legal timber supplies.
The good news however, is that improving enforcement is slowly making things tougher for illegal loggers.
Accustomed to dealing with criminal enterprises that transcend international borders, Interpol is bringing a new level of sophistication to the war on illegal logging. This is timely because most current efforts to fight illegal logging – such as the European Union’s Forest Law and various timber eco-certification schemes – just aren’t designed to combat organised crime, corruption and money laundering.
The Interpol report urges a multi-pronged approach to fight illegal loggers. A key element of this is anti-logging legislation that makes it harder for timber-consuming nations and their companies to import ill-gotten timber and wood products. Read the rest of this entry »
As is their wont, Nature declined to publish these comments (and our responses) in the journal itself, but the new commenting feature at Nature.com allowed the exchange to be published online with the paper. Cognisant that probably few people will read this exchange, Bill Laurance and I decided to reproduce them here in full for your intellectual pleasure. Any further comments? We’d be keen to hear them.
In this paper, Laurance and co-authors have tapped the expert opinions of ‘veteran field biologists and environmental scientists’ to understand the health of protected areas in the tropics worldwide. This is a novel and interesting approach and the dataset they have gathered is very impressive. Given that expert opinion can be subject to all kinds of biases and errors, it is crucial to demonstrate that expert opinion matches empirical reality. While the authors have tried to do this by comparing their results with empirical time-series datasets, I argue that their comparison does not serve the purpose of an independent validation.
Using 59 available time-series datasets from 37 sources (journal papers, books, reports etc.), the authors find a fairly good match between expert opinion and empirical data (in 51/59 cases, expert opinion matched empirically-derived trend). For this comparison to serve as an independent validation, it is crucial that the experts were unaware of the empirical trends at the time of the interviews. However, this is unlikely to be true because, in most cases, the experts themselves were involved in the collection of the time-series datasets (at least 43/59 to my knowledge, from a scan of references in Supplementary Table 1). In other words, the same experts whose opinions were being validated were involved in collection of the data used for validation.
Much of conservation science boils down to good decision making: when, where and how we ‘set aside’ terrestrial or marine areas for specific protection against the ravages of human endeavour. This is the basis for the entire sub-discipline of conservation planning and prioritisation, and features prominantly in most aspects of applied conservation and restoration.
In other words, we do all this science to determine where we should emplace protected areas, lobby for getting more land and sea set aside so that we have ‘representative’ amounts (i.e., to prevent extinctions), and argue over the best way to manage these areas once established.
But what if this pinnacle of conservation achievement is itself under threat? What if many of our protected areas are struggling to insure biodiversity against human consumption? Well, it’d be a scary prospect, to say the least.
Think of it this way. We buy insurance policies to buffer our investments against tragedy; this applies to everything from our houses, worldly possessions, cars, livestock, health, to forest carbon stores. We buy the policies to give us peace of mind that in the event of a disaster, we’ll be bailed out of the mess with a much-needed cash injection. But what if following the disaster we learn that the policy is no good? What if there isn’t enough pay-out to fix the mess?
In biodiversity conservation, our ‘insurance’ is largely provided by protected areas. We believe that come what may, at least in these (relatively) rare places, biodiversity will persist despite our relentless consumerism.
Unfortunately, what we believe isn’t necessarily true.
The Grand ACEAS Workshop was something of an experiment: what will happen when we bring 30 of Australia’s top scientists working on land management issues into the same room?
The Grand Workshop participants came from academia, research institutions and the government, and had all received ACEAS funding for working groups. David Keith, Ted Lefroy, Jasmyn Lynch, Wayne Meyer and Dick Williams were amongst the attendees of the two-day workshop.
And when this group of people came together wanting to analyse and synthesise ecological data, great things happened.
“We decided to focus on how carbon pricing legislation will affect land use change and how will that spill over into biodiversity persistence”, said Professor Corey Bradshaw, Director of Ecological Modelling at The University of Adelaide, who led the synthesis activity at the Grand ACEAS Workshop.
“Will carbon pricing lead to good outcomes for biodiversity, or negative ones, or will it have no bearing whatsoever?”
The workshop participants broke into five groups to discuss how the carbon tax legislation will change land use when it is introduced in July 2012, and the potential impact on biodiversity.
Some of the questions asked included:
Is it enough simply to allow plants to re-grow to be eligible for carbon credits?
How will an increase in forestry plantations impact biodiversity, water catchments and fire regimes?
Will there be more kangaroo grazing to reduce methane emissions and erosion, replacing hard-hoofed livestock?
Can you receive carbon credits for shooting large feral animals like goats, camels, deer and boars?
The groups found many opportunities for positive biodiversity outcomes with the carbon sequestration activities encouraged by carbon pricing, but there are also many potential ‘bio-perversities’. Read the rest of this entry »
Some of you might be aware that the Australian Commonwealth Government has just released its Draft National Wildlife Corridors Plan for public comment, but many of you might not really know what a ‘corridor’ constitutes.
Wildlife or biodiversity ‘corridors’ have been around for a long time, at least in terms of proposals. The idea is fairly simple to conceive, but very difficult to implement in practice.
At least for as long as I’ve been in the conservation biology biz, ‘corridors’ have been proffered as one really good way to make broad-scale landscape restoration plausible and effective for (mainly) forest-dwelling species which have copped the worst of deforestation trends around Australia and the world. The idea is that because of intense habitat fragmentation, isolated patches of primary (or at least, reasonably intact secondary) forest can be linked by planting some sort of long corridor of similar habitat between them. Then, all the little creatures can merrily make their way back and forth between the patches, thus rescuing each other from extinction via migration. Read the rest of this entry »
Here’s another great post from Salvador Herrando-Pérez. It is interesting that he’s chosen an example species that was once (a long, long time ago in a galaxy far, far away) of great interest to me (caribou – see ancient papers a, b, c, d). But that is another story. Take it away, Salva.
–Figure 1. Caribou (reindeer) are ungulates weighing up to ~ 100 kg. They live in tundra and taiga in Finland, Greenland, Finland, Norway, Mongolia, Russia, Canada and USA (extinct in Sweden). The species is globally stable (‘Least Concern’, IUCN Red List), but the subspecies of woodland caribou (Rangifer tarandus caribou) is threatened in North America. Schneider and colleagues’ 7 study encompasses ~ 3,000 individuals in 12 herds (75 to 450 individuals per herd), occupying ~ 100.000 km2 of conifer forest and peatland (3,000 to 19,000 km2 per herd). Two ecotypes are recognized regionally22, namely migratory mountain herds (mostly from mountains and foothills in west-central Alberta), and non-migratory boreal herds (mostly from peatlands in central and northern Alberta). The photo shows a group of caribous grazing on subalpine vegetation from Tonquin Valley, Jasper National Park (Alberta, Canada). Photo courtesy of Saakje Hazenberg.–
As conservation biology keeps incorporating management and economical principles from other disciplines, it stumbles with paradoxes such that investing on the most threatened components of biodiversity might in turn jeopardize the entire assets of biodiversity.
At the end of 2011, newspapers and TVs echoed an IUCN report cataloguing as ‘extinct’ or ‘near extinct’ several subspecies of rhinos in Asia and Africa. To many, such news might have invoked the topic: “how badly governments do to protect the environment”. However if, to avoid those extinctions, politicians had to deviate funds from other activities, what thoughts would come to the mind of workers whose salaries had to be frozen, school directors whose classroom-roof leakages could not be repaired (e.g., last winter at my niece’s school in Spain), colonels whose last acquisition of ultramodern tanks had to be delayed, or our city council’s department who had to cancel Sting’s next performance.
Thus, there are three unquestionable facts regarding species conservation:
the protection of species costs money;
governments and environmental organisations have limited budgets for a range of activities they deem necessary; and
our way of conserving nature is failing because, despite increasing public/private support and awareness, the rate of destruction of biodiversity is not decelerating1,2.
One of the modern debates among conservationists pivots around how to use resources efficiently3-6. Schneider and colleagues7 have dealt with this question for woodland caribou (Rangifer tarandus) in Canada. A total of 18 populations of this ungulate persist in the Canadian province of Alberta, all undergoing demographic declines due to mining extractions (oil, gas and bitumen), logging and wolf predation. The species is listed as ‘threatened’ regionally and nationally. The Alberta Caribou Recovery Plan (2004-2014) is attempting to protect all herds. Under such a framework, Schneider et al.7 predicted that woodland caribou would be regionally extirpated in less than a century.
Furthermore, they estimated the costs of making each herd viable (Fig. 1), with a triple revelation. To save all herds from extinction would need ~ CA$150,000 million (beyond the available budget). The most threatened herds are among the most expensive to protect (within present management approach). Some herds would be secured through modest investment for two decades. Overall, their study suggests that Alberta’s woodland caribou would be eligible for triage, i.e., at the subpopulation level8. Read the rest of this entry »
This last post before Easter is something I’ve thought more and more about over the last few years. I wouldn’t have given it much time in the past, but I’m now convinced roads are one of the humanity’s most destructive devices. Let me explain.
Before I had a good grasp of extinction dynamics, I wouldn’t have attributed much import to the role of roads in conservation. I mean, really, a little road here and there (ok, even a major motorway) couldn’t possibly be a problem? It’s mostly habitat destruction itself, right?
I’ve mentioned this idea before, but it’s nice when some real data support a prediction (no matter how gloomy that prediction might have been). It’s what drives scientists toward discovery (or at least, it’s what I find particularly appealing about my job).
Several years ago, my colleagues (Navjot Sodhi† and Ian Warkentin) and I wrote a major review in TREE about the fate of the world’s ‘second’ lung of the planet, the great boreal forests of Russia, Canada & Scandinavia. We discussed how fragmentation was increasing at an alarming rate, and that although most species there are still relatively intact, we stand to lose a lot of its biodiversity if we don’t halt the fragmenting processes soon. We wrote more on the subject in a paper to appear imminently in Biological Conservation.
Another component though that we raised in the TREE paper was the boreal forests were very much in danger of turning into a net carbon producer. You see, the ‘lung’ analogy is very pertinent because on average, the growth of the massive expanse of the vegetation in the forest generally takes up much more atmospheric carbon that it exudes through decay and burning (for as we all know, plants take up carbon dioxide to produce sugars during photosynthesis, and produce oxygen as a ‘waste’ product). However, as we fragment, cut down and burn the forest, it can end up producing more than it takes up (i.e., turning from a ‘sink’ to a ‘source’). We highlighted several studies indicating how insect outbreaks and human-exacerbated fire intensities and frequencies could conceivably do this.
Australia’s > 800,000-km road network would go 60 times around the equator of our planet. Confined to the boundaries of any one country, roads are a conspicuous component of the landscape, and shape the dispersion, survival and reproduction of many plants and animals in urban and remote areas.
Those who drive (or are driven by) will be familiar with the image of a crushed kangaroo on the roadside (a hedgehog in Europe), or the sticky mosaic of insects smashed against the windscreen after a high-speed run. Mortality by collision is one of the many effects that roads can have on the demography of organisms – including humans. Those effects encompass
physical alteration of terrestrial and aquatic habitats,
chemical pollution leakage during road construction and maintenance, and from asphalt compounds during storms,
alteration of animal behaviour (e.g., change in home range, or in patterns of flight or vocalisation),
access to remote areas by hunters, fishermen and gatherers in general, and
intense habitat fragmentation1-3.
However, some species get around those negative impacts by using the roads as pathways to new territories, thereby eluding barriers like seas, mountains, rivers, dense vegetation, or competition for vital resources with other species. Read the rest of this entry »
We live in an era of unprecedented road and highway expansion — an era in which many of the world’s last tropical wildernesses, from the Amazon to Borneo to the Congo Basin, have been penetrated by roads. This surge in road building is being driven not only by national plans for infrastructure expansion, but by industrial timber, oil, gas, and mineral projects in the tropics.
Few areas are unaffected. Brazil is currently building 7,500 km of new paved highways that crisscross the Amazon basin. Three major new highways are cutting across the towering Andes mountains, providing a direct link for timber and agricultural exports from the Amazon to resource-hungry Pacific Rim nations, such as China. And in the Congo basin, a recent satellite study found a burgeoning network of more than 50,000 km of new logging roads. These are but a small sample of the vast number of new tropical roads, which inevitably open up previously intact tropical forests to a host of extractive and economic activities.
“Roads,” said the eminent ecologist Thomas Lovejoy, “are the seeds of tropical forest destruction.”
Despite their environmental costs, the economic incentives to drive roads into tropical wilderness are strong. Governments view roads as a cost-effective means to promote economic development and access natural No other region can match the tropics for the sheer scale and pace of road expansion. resources. Local communities in remote areas often demand new roads to improve access to markets and medical services. And geopolitically, new roads can be used to help secure resource-rich frontier regions. India, for instance, is currently constructing and upgrading roads to tighten its hold on Arunachal Pradesh state, over which it and China formerly fought a war.