p. 92 "There are also ecosystem stressors that are the result of actions or activities that are largely beyond the control of public land managers. Examples of these include: mercury contamination of aquatic ecosystems that comes from a variety sources; acid deposition that may cause significant stress to lakes, streams, and forest ecosystems, especially to those at higher elevations; large hydropower facilities that may obstruct anadromous fish passage to upstream spawning areas; changes to vegetation conditions in Central and South America that may affect wintering populations of migratory birds that breed and nest in North America; and potentially dramatic changes to ecological conditions due to global climate change."
|We are running out of time|
|Just because you can't see it, doesn't mean it isn't there|
a study published New Scientist brings the sorrowful but unsurprising conclusion that the world's oldest and most venerable tree specimens are dying off all over the globe. Naturally, this is attributed to localized diseases, insects, or drought, without once mentioning the single underlying factor they share in common: air pollution.
"Fragmentation of the forests is now disproportionately affecting the big trees," said William Laurance, a research professor at James Cook University in Cairns, Australia. "Not only do many more trees die near forest edges, but a higher proportion of the trees dying were the big trees."
"Their tall stature and relatively thick, inflexible trunks, may make them especially prone to uprooting and breakage near forest edges where wind turbulence is increased," said Laurance in this week's New Scientist magazine.
"'The danger is that the oldest, largest trees will progressively die off and not be replaced. Alarmingly this might trigger a 'positive feedback' that could destabilise the climate: as older trees die, forests would release their stored carbon, prompting a vicious circle of further warming and forest shrinkage,' said Laurance."
"Many of the big trees are the oldest and most ecologically important inhabitants of the forest. In the Amazon, they are often 400-1,400 years old, in North America giant redwoods can exceed 2,000 years and giant sequoias 3,000 years."
"...forests would release their stored carbon, prompting a vicious circle of further warming and forest shrinkage." Yep! Except it's not a "future danger", it's already occurring. And it's not just the oldest trees that are dying, although obviously, they have suffered more cumulative exposure than young trees - but now the young are dying at a rapidly accelerating rate, too. They all have to absorb the same toxic gases.
a graph from a UNEP report, of anoxic areas in the ocean. Too much pollution creates algal growth, which gobbles up all the oxygen that other forms of life in the sea need to survive:
"Fertilizers such as nitrogen and phosphorous are essential to global food security and have played a key role in increasing crop yields. But inefficient use of nutrients is contributing to the degradation of marine ecosystems and groundwater, including the formation of oxygen-poor 'dead' zones. The amount of nitrogen reaching oceans and coasts has increased three-fold from pre-industrial levels - primarily due to agricultural run-off and untreated sewage. This could expand by up to 2.7 times by 2050 under a 'business as usual' scenario." [It's not just that it's inefficient use. There's simply too much use - because there are too many people!]
"Mainly due to the addition of manufactured nitrogen (from atmospheric nitrogen and natural gas), the amount of reactive nitrogen entering the earth’s biogeochemical system has increased by about 150% compared to pre-industrial times. A 2009 Nature Report, “A Safe Operating Space for Humanity”, determined that excess nitrogen in the environment was one of 3 of the 9 ‘planetary
boundaries’ that had already been exceeded. In effect, mankind is ‘mining’ the atmosphere for nitrogen; with a practically limitless supply, this process could proceed for hundreds if not thousands of years leading to continually worsening conditions for coastal areas and groundwater."
"The environmental and socioeconomic impacts of nutrient pollution are massive and occurring over wide areas globally. The occurrence of coastal hypoxic zones caused by eutrophication has increased exponentially in recent years, and nitrate pollution is one of the main groundwater contaminants in the developed and also increasingly in the developing world. Coastal hypoxia impacts fisheries, tourism and various ecosystem services provided by healthy coastal ecosystems. For the EU alone, the economic costs of damage to the aquatic environment from excess reactive nitrogen are estimated at up to € 320 billion per year. Initial evidence from the EU and US suggests that the overall benefits from improved nutrient management exceed costs and that this cost/benefit calculus occurs in other parts of the world."
In fact, as depicted in this map from the EPA, there doesn't appear to be a single area of the US coast that isn't subject to harmful algal growths of one sort or another!
"When some types of algae bloom in significant amounts and produce chemicals referred to as biotoxins, the event is called a harmful algal bloom (HAB). HABs can occur in freshwater (e.g., lakes, reservoirs, rivers, ponds), estuaries, and coastal waters. The biotoxins from HABs can harm humans or the environment through the production of toxins, noxious odors, or excessive growth. HABs include different types of algal species including microscopic dinoflagellates, diatoms, and cyanobacteria (formerly known as blue-green algae). Domoic acid, which is produced by marine diatoms, is a well documented toxin that has killed people and large numbers of marine animals. In freshwater, cyanobacteria is of concern because of its occurrence in water used for drinking and recreation."
Oh and lest we forget, reactive nitrogen that dissipates into the air from agricultural applications, and from fuel combustion, converts to tropospheric ozone, too! If we continue to emit invisible toxins on this massive scale, we will soon transform paradise into this world:
Find lab analysis of air pollution on this site.ReplyDelete
Wow, I can't believe they used that picture. Well at least the little trees clumped together in the middle look ok.ReplyDelete
I was just walking through the outskirts of Burn's Bog here in SW BC yesterday and have to say that place is in really rough shape as far as trees go, probably the worst I've seen of all the protected areas around here. Although surprisingly enough there are absolutely tons of young hemlocks anywhere from seedlings to what looks to be about 10 years old that appear to still be thriving. I wonder if they'll eventually replace all the other trees in the area. Obviously a pure hemlock forest is not going to support the kind of diversity we're used to seeing in the area.
Gail, have you ever thought of doing a comparison if some pictures could be found say 30 years ago of what a certain species should look like if it is relatively healthy?ReplyDelete
I find so many obvious examples of dying or dead trees that no one should miss, yet I find many where I wonder if they are not still within the parameters of what might be considered normal. The problem with shifting baselines is that it can be difficult to discern sometimes what a tree should actually look like if it were totally healthy.
What is considered healthy today may have been considered to be in rough shape 30 years ago, It's hard to say without comparison.
The pictures from this book should give you an idea of how big trees can grow in a clean environment:ReplyDelete
One of the reasons I think that we have a huge problem is that the leaves of the deciduous trees, shrubs and annual plants during the past 2 growing seasons pretty much all exhibited damage - chlorosis and worse. And the literature is quite clear that trees can have internal damage - shrunken roots, for example - well before there is visible injury on foliage or needles.
Don't forget, a cut Christmas tree can look alive even though it's obviously not.
I did do a few comparisons, one in Central Park:
and in northern NJ, the same park 2007, 2009 and 2010: http://witsendnj.blogspot.com/2010/11/acidification.html
Not 30 years of course. I'll google around and see what I can come up with.
Keep in mind that scientists who are methodically measuring tree mortality concede that there is an ongoing trend for them to be in decline, they would just rather pin it on climate change. Pollution seems to be a very unpopular topic.
Pollution seems to be a very unpopular topic.ReplyDelete
Bingo! Even the warmer science poses risks from methane as greater than co2 It is also why I shake my head over losing emphasis on known toxins and conditions entering the environment in favour of yelling about a balance of rising co2. One cannot use temperature data that hasn`t yet occurred to prove the proposition. Yet not waiting means - which would be futile of course - also you have left the realm of knowledge. End result : no reliable data.
Taxing fire use is a wry joke on the gullible.
Even while you think my rejection of media reports of scientific consensus wrong, you shouldn`t discount the effects of a loss of focus on pressing issues.
Have you read the Sourcewatch information on coal ash yet
I do not recall trees looking like that either before say 20 years ago. That would roughly coincide with smog on the prairies - where`the air is so clear` ìs but a faint memory.