Recently in Geography Category
This problem is hardly new, I think. Although the author did mention that the rapidly increasing foreign trade ports and airports in China makes the control of imported horticulture products more difficult. Apparently, species emigration and immigration happens at the same time on both borders. This is a new challenge to biodiversity conservation, and perhaps a result of globalisation. The problem is as old as trade itself, but nowadays at a completely different scale. Impact can be limited, though, if both sides take actions.
From ScienceDaily:
GENESI-DR (Ground European Network for Earth Science
Interoperations - Digital Repositories), an ESA-led, European
Commission (EC)-funded two-year project, is taking the lead
in providing reliable, easy, long-term access to Earth Science
data via the Internet.
In practice, institutions have done the same thing at a much smaller scale — within their organisation. From the description, it looks like Open Access of Earth Science data, which is quite exciting news for us in Europe. However,
GENESI-DR will allow scientists from different Earth Science
disciplines located across Europe to locate, access, combine
and integrate historical and fresh Earth-related data from
space, airbourne and in-situ sensors archived in large
distributed repositories.
Does this mean that it is only “by Europeans, for Europeans”? It would be great if ESA can get the U.S. on board, who is at present the biggest RS and other ES data provider with some of the best equipment.
Crisis in the Drylands: Scientific American
If you do not want to be unpopular, just remember to criticise Mr. Bush and his “War on Terror”. However, after we attribute conflicts to everything from imperialism to terrorism, from religion to civilisation, I am glad to see finally some opinions which reflect on the trapped, or failure state in many arid areas, from a different aspect which has very little to do with politics and military. The article states that:
Washington looks at many of these clashes and erroneously sees Islamist ideology at the core. Our political leaders fail to realize that other Islamic populations are far more stable economically, politically and socially—and that the root of the crisis in the dryland countries is not Islam but extreme poverty and environmental stress.
The article gracefully followed this issue by discussing what is the cause of these areas’ unfavourable state, why military approach is not working and what economic and environmental measures should be taken to salvage these areas and people. The measures include solving water shortage, increasing productivity, building infrastructures and establishing export market. However, to apply the article’s suggestion without consideration to all arid environments in such crisis may not be justified. As each area have differing situation and conditions, and the history before they fall to the undesirable state may be worthy looking at.
I would argue that resilience, and afterwards adaptive cycle and panarchy, can be used as a framework when studying such problems. The objective of improvement, is not only bring people out of poverty, but also ensure that they do not fall into poverty again when another drought or war strikes, i.e. make them more resilient to changes.
To achieve this, one question must be answered is “what state on earth is the system in?”. If we use the ball and basin analogy, we say the system is “trapped” in a state because there is some forces that stop the system from shifting state, just like the terrain around a basin stops the ball from falling out. These forces may be brought by the interactions of slowly and fast changing variables. The article in SA noticed fast changing variables but often the slow ones are more fundamental.
It can be very tricky to find the slowly changing variable, especially in a complex system. An examination of the system’s history sometimes can help. By identifying different periods when the system is more organised or chaotic, or when it is more resilient or more rigid, and compare variables we can get hold of, we may be able to identify slowly changing variables. We can also identify significant changes in the history and examine its impact. This is where the adaptive cycle comes into play. The problem with this approach, however, is that the measures of resilience, connectedness and capital (the three dimensions in the cycle metaphor) are still quite subjective nowadays. But comparison and qualitative analysis is possible.
From the adaptive cycle we can find out how the slowly changing variables influenced the resilience, connectedness and capital varied throughout the history, god-willing, we will be able to tell how they influence the system today. The next step, given slowly changing variables, is to optimise fast changing variables so as to change the shape of the “basin” so the “ball” can fall into a better basin (if any, that is) than the current one.
Back to measures proposed by the SA article, they are all trying to change the fast changing variables, such as water availability and grassland productivity. However without knowledge of slowly changing variable, such as soil texture, organic content, and/or precipitation, such manipulation may well be futile. Not to mention there are also socioeconomic factors in play, e.g. local customs, the psychology of local people and occupant, and the impact of foreign culture. These are even more intriguing to define and quantise.
In a word I think it is correct to begin to address dryland crisis from environment and economy sector instead of military and ideology ones. Yet the frustrating complexity should be covered if long term interest of the system is desirable. So far the most promising helper seems to be the resilience/panarchy network.
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I think I am a bio-fuel advocate-turned-skeptic now.
Both NewScientist and SciAm report that a native North American perennial grass, switch grass Panicum virgatum can produce 540% of the energy used to grow it. It has been naturally growing at field margins in U. S. for years, yet recently become a new focus in bio-fuel development. Without doubt its efficiency in producing energy beats the criticism that bio-fuel growing is not energy-efficient. It even has nearly permanent underground root system that offset 94 percent of the greenhouse gases emitted to cultivate it and from derived ethanol. Neat isn’t it?
However I think environment aware farmers will face certain dilemma when they decide whether to plant it or not. By definition it can be grown on marginal land without intensive care. But it would take many households’ yield to form a quantity that is worth further process. The ethanol yield on a field is 2,000 to 3,500 litres/ha, which about equals to 1,300 to 2,250 litres of petrol (using data from here and here). For an average truck that carries the grass from a farm to refinery, the fuel supports it to run for 860 to 1,500 kilometres (using 2005 data from here). There was not an estimate of farm-refinery data that I can find, but this report claims that local food travels on average 56 miles to reach institutional market, convert this to kilometres and times 2, the travel from a refinery to a farm and back along takes about 180 kilometres. This part was not calculated in the model used to calculate net energy yields. Considering that the bio-fuel production is very distributed, it is necessary to incorporate this into the analysis. If the switchgrass is really grown on marginal land, it is very possible that the collector will need to travel more miles before obtaining adequate amount of raw materials for production.
If the grass is grown in field scale, not on marginal land, problems for other bio-fuel plants also exist: investment of land and water, fertilizers and so on. Like all technology, it is dangerous if people are too obsessed and invest their land and money blindly on the switchgrass. With a similar unit area ethanol yield to corn, it still will take considerable land to make the production practical and profitable. The discovery itself is remarkable. But it will not be the single solution to energy problem in the US, nor should it become an excuse to put more greenhouse gases into the atmosphere.
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http://www.sciencemag.org/cgi/content/full/318/5856/1540
This may not be the most exciting archaeology discovery in the history. As we already know that some tribes Indians have lived on the high cliffs in Utah which were virtually unreachable. However, the disappearing of these tribes from those cliffs reveals an unsettling question: was climate the driving factor?
Evidences show that the possibility is significant, as the article tells. However, what raised my interest to blog it was this paragraph:
The impact was all the harder because of the previous and intervening wet years, researchers suspect. There’s evidence that after each drought the Fremont rebounded as climate improved. “Each time they did that, there seems to be a population boom,” says Steven Simms, a Fremont scholar and archaeologist at Utah State University in Logan. But those extra mouths to feed demanded more crops, leaving the culture even more vulnerable to the next dry spell.
This leads my thought to my research area, which was also struck by snowstorms and/or droughts almost every year. Nowadays the people there barely manage to recover after the disasters, therefore the population is only slowly increasing according to official census data. However, the case would be different if they are changed to another mode of life which is more resistant against natural disasters. Could a similar pattern appear afterwards? Will they become more resistant but less resilient and suddenly become fragile in the face of a major disaster? Or, anything similar has happened in the history?
My research needs a conceptual model. At present, I think it would be desirable to have a social dimension aside of the ecological one. Therefore, in the conceptual model, I need not only links denoting the flow of nutrient and energy, but also those representing flow of ecosystem services, which can be considered as the interface between the “human” and the “nature” parts in the system.
But “ecosystem service” would be too abstract to use even in a conceptual model. A concrete, and more desirable if universal surrogate of these services is needed. I am very reluctant to use monetary measures as there are many values that cannot be underestimated using such an approach.
A search at Google Scholar gives about 200 results using keywords “ecosystem services” and “surrogate”. After a browse I cannot say that I find much enlightenment, although this one is interesting. Non-linearity and changes should be considered when choosing the sorrogate. But it will not do if too many factors are considered, right?
Biodiversity is another often (ab-)used surrogate. But it is surely not adequate for the area I am studying, as the productivity there is so limited that it can only support a relatively simple system. The only way to achieve “diversity” is eutrophication, not like an option.
Or as an alternative, the energy flow combined with monetary evaluation can be used as the measure of ecosystem service?
I did some experiment with GPS Visualizer which I mentioned yesterday. I used it to visualise some Landsat images that I can use for my research.
In this screenshot you can see three overlays generated from Landsat visual images provided by Jet Propulsion Laboratory, NASA. If you take a closer look at places where these images overlap you will find that the quality of registration is very impressive. However, GPS Visualizer seems not able to control the skewness of the image, all overlays are rectified to the latitude and longtitude, which is not the direction of Landsat’s nadir path (shown in the image as a white line). Anyway, using it I can get an idea of the satellite coverage of my study area (red box) without using complicated GIS/RS software packages.
This is an essential for geography hobbists and serious GE users. Without a flashy interface (yet?), this site provides a rich set of tools to help you visualise geographic data on Google Maps and Google Earth. Haven’t got time for all its features, but the first thing I am going to do with it is to create a Landsat overlay of my study area. More details in later posts.
BBC NEWS | World | Americas | Biofuels ‘crime against humanity’
There is yet another voice to express the concerns behind the large scale adoption of biofuel crops, especially corn. It has been pointed out by Mr Ziegler that plantation of biofuel crops has already led to decrease of available arable land, and the increase of food price.
This seems to be one thing that market cannot solve satisfyingly. If we rely solely on price and demand to adjust the production of food and biofuel, it can be expected that farmers will always have incentives to plant corn to produce ethanol before the price of biofuel is the same as fossil fuel. At the same time food price will also rise and leave more people in hunger. But farmers will not turn to food production until food price (combined with subsidies, maybe) is high enough to provide revenue as good as fuel. By then millions would have starved.
A threshold should be determined which states the maximum land and other resources allocated to biofuel production and should be enforced as a law. If we cannot determine the threshold yet, I think it is another time to apply precaution principle and set a safe limit. At the same time attempts to reduce fuel consumption and improve fuel efficiency should always be encouraged.
On the other hand, Food and Agriculture Organization in 2005 considered biofuel as a key to fight against hunger, as it reduces the import bill as well as brings investments and jobs. But that argument seems to miss the resource part, ignoring food production while it examines hunger.
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Today I attended a lecture given by Alan Bullin with the topic “Biofuels in the Asia-Pacific”, which is just a general review of the situation of biofuel legislation, adoption and application in developed and developing world. But my question would be, how biofuel crops affect the resilience of farmers who adopted them out of economic interest?
I asked this because I thought of farmers in China. If they know this is going to make money you can bet they will begin to plant sugarcanes overnight. However, their relatively slow rate to access relevant information means they are very likely to encounter market failures and have losses. On the other hand, the question is also about long-term perspectives. If one day we suddenly do not need biofuel and fossil fuels anymore (invention of safe and cheap hydrogen/nuclear/solar/you-name-it energy technologies), will the farmers be able to quickly and easily turn to other income sources?
Dr. Bullin’s answer to the questions, as I perceived, is that the market will determine what the farmers plant, the adoption of new energy will not be sudden, but a gradual process. The competition between various biofuel crops means the farmers will not be trapped in one crop and cannot get themselves out. They can always turn to another kind of biofuel. Of course, in the market, there is always risk.
I did not mention resilience or China’s immature market in my question, which may change his answer a bit. On a second thought, the farmers may not always have alternatives due to climate and hydrology restrictions. I still would like to know whether farmers can turn their sugar cane field into, say, potato garden quickly enough. There have already been some studies on biofuels and resilience. Many of them expressed optimistic evaluation of this new technology concerning long-term gains and resilience, stating their positive role in the conservation of forest and reduction of carbon. However, I do think there is some negative issues that should be scrutinised carefully, for example, increased food price [1], changed land use and threat to natural area/food production [2], and Fairtrade concerns.
- Kill king corn. Nature 449, 637 doi: 10.1038/449637a (2007).
- Fuelling controversy — can biofuels slow the speed of climate change?
