A couple of weeks ago, I called Dr. Gretchen Smith, who back in 1994 designed and still heads the USDA Forest Service Ozone Biomonitoring Program, to ask her to send me some more information.
To: "Wit's End"
Date: Monday, September 6, 2010, 12:32 PM
I have attached the most relevant General Technical Report published by the Forest Service. Each region has also published smaller more focused reports, 2 from the PNW and 1 from the South, and there have been 4 peer-reviewed articles, based on the results, published in the scientific journals.
The physiological changes observed in the presence of O3 polluted air are reduced net photosynthesis, increased respiration rate, membrane lipid peroxidation, enhanced rate of senescence, reduced transpiration, and inhibition of translocation to roots....etc.
When ozone gets inside the plant by moving unobstructed along the CO2 pathway through open stomates, it will have an adverse effect on numerous physiological processes, almost any you could name. However, the highly reactive ozone molecule itself is long since gone and in that sense is not measurable or even detectable inside the plant. The studies that use physiological disruption to describe ozone injury are done under controlled conditions in greenhouse fumigation chambers so that the cause and effect can be linked appropriately. In the real world, in nature, these same effects may be observed, but there is no good way to attribute them to ambient ozone alone. A wide variety of other natural and man made stress factors will cause similar effects. The visual symptoms on well tested bioindicator plants are still the best way to know high ozone levels have been in a particular place at a particular time. And, it remains true that if the stomates are closed, the ozone molecule can not get into the plant and injury does not occur. Ozone is a highly reactive molecule and the second it contacts any surface whether the ground, or the side of a building, or the surface of a leaf, or your lung tissue it will be incorporated into 'normal' molecules or revert back to oxygen and effectively disappear. The following web sites may give you some idea of the number of national agencies that are working on the ozone problem.
Thank you for your interest,
EPA web site that allows access to scientific review papers that contributed to revised standard
FS web site for the biomonitoring program; Needs update, but several publications, data and maps are accessible by links.
NPS web site that summarizes their national biomonitoring work
Al Lefohn's web site: Independent Researcher
[now this is a bit astonishing considering what we know about Al Lefohn!]
The Heinz Center web site
I have been reading your report and the other links you sent. Thank you again so much for providing a wealth of information.
I'm working on a post for my blog and I have a few questions, I hope you don't mind clarifying.
1. I cannot find any information about results from the biomonitoring program for the summers of 2008, 2009 and 2010. This is my main interest because it was in the summer of 2008 that I noticed all the leaves on the trees - trees of all species and all ages in every location - abruptly wilted, in August.
If you can you direct me to a link or publication which compares the most recent seasons results with past years that would be invaluable.
2. In your report it is stated in several places that ozone does not directly kill trees, but exposure can encourage other pathogens or insects which then will kill the trees. My question is, isn't this kind of like saying a person with AIDS died from pneumonia - even though they never would have died of pneumonia if they didn't have AIDS? In that sense, isn't it misleading?
Also, from what I have seen, ozone (or something else in the atmosphere) IS killing trees directly because some of them are dying without any insects on them. Although, no doubt some of them have internal fungus, they are growing enormous cankers, and seeping sap. But it also looks like just dropping leaves - or closing their stomates - is enough to kill them.
In other places in your report, it is stated that entire ecosystems can be altered as ozone-sensitive species are replaced by more ozone-tolerant species. Wouldn't that imply that the ozone is killing off the sensitive species?
3. In the introduction of the report, it is mentioned that lichen monitoring is part of the ongoing study. Is there a lichen monitoring component? This is very interesting to me because I have noticed an unprecedented spread of lichens on tree trunks and branches which is closely associated with their decline - whether it contributes to the decline or just takes advantage of it, I don't know. Either way, it is certain that once the lichen starts growing, the tree's days are numbered. I've read that certain lichens thrive in nitrogen pollution so I am curious if you have detected a proliferation of nitrogen-loving lichens.
4. In your biomonitoring program do you tally the production of fruit or nuts or seeds - or do you know of any other program that does? I have read that ozone diminishes reproductive capability, which I have seen for myself. Last year a West Virginia agency published a really alarming study that there was not enough "mast" for wildlife to eat.
5. I haven't been able to find a direct reference to the Biomonitoring Program in the labyrinthine EPA webpages, but that doesn't really matter, I'm sure it's there somewhere! What I would like to know is, given that they revised their standards, do you think based on the condition of trees that the new standards are adequate to protect vegetation?
Thank you so much for your attention. I hope you don't think I am being antagonistic by asking questions - I am looking for help. I love trees and it is breaking my heart to see them die off so quickly. It also terrifies me because I don't see how people can survive without them. From what I can see - and I have seen the same widespread, acute damage from Boston to Virginia, in California, the Olympic Peninsula, and in Costa Rica - we have to determine what exactly is going on and take steps to fix it before the entire ecosystem collapses.
The pictures I sent you are absolutely typical in New Jersey right now - some trees look a bit greener and thicker - others are completely dead without a single leaf - many have been removed. Notice how in the picture labeled "wires" there are areas of just plain dirt. This can be found all over and I have never seen it before in my life until this summer. As a gardener who has pulled thousands of weeds, I know that "nature abhors a vacuum". For there to be so much earth with absolutely nothing growing on it is bizarre, to say the least - and it's not just in populated areas around parking lots, it has become common in fields and in the woods (I live out in a very rural area).
One last question:
6. Assuming for the sake of argument I am correct - something in the air is killing vegetation in the geological blink of an eye - do you think it could be attributable simply to the inexorably rising levels of ozone? A tipping point, in other words? I wonder if the emissions of ethanol - which in the very few existing studies investigating acetaldehyde are supposedly worse than those of gas and coal - could be the primary causative agent. I have also considered increased UV radiation (supposedly, solar storms in 2005 and 2007 depleted stratospheric ozone) or radiation from cell towers and phones could perhaps increase ozone. Any thoughts you have on this issue would be greatly appreciated.
Along with the other useful links, Dr. Gretchen Smith included this pdf of a study she coauthored for the USDA Forest Service, "Ozone Bioindicators and Forest Health: A Guide to Evaluation, Analysis, and Interpretation of the Ozone Injury Data in the Forest Inventory and Analysis Program." Unfortunately, this paper was submitted for publication in April of 2008, so it cannot account for what I have personally observed, which is the wholesale, rapidly accelerating decline that began in August of 2008 and continues unabated.
"Tropospheric O3 is toxic to humans beings, plants, and many other life forms. Before the industrial age, the lower atmosphere was relatively free of O3. Today, this toxic contaminant is found across all geographic and political boundaries and in areas previously believed to be pristine. Plant scientists consider ground-level O3 the most pervasive air pollutant worldwide and a threat to world food, fiber, and timber production and conservation of natural plant communities (Percy et al. 2003). Trends in surface O3 concentrations indicate an increase in background O3 concentrations over much of the world and a huge increase in the extent of forest areas at risk of O3 exposure."
Well, that seems pretty unequivocal!
On page 5, Ozone Uptake and Plant Response:
"Open stomata provide the pathway for O3 entry into the leaf. Once inside the leaf, O3 immediately forms toxic derivatives that react with many components of the leaf cells. Many studies of foliar response to O3 show that the cell membranes suffer the most injury characterized by changes in permeability and leakiness to important ions such as potassium...The first reaction to injury by oxidants is loss of chlorophyll, increased fluorescence, and changes in energy levels. As injury progresses and antioxidants come into play, carbon fixation is reduced, foliar and root respiration is increased, and there is a shift in the partitioning of carbon into different chemical forms and allocation patterns. At the most basic cellular level, a plant injured by O3 is not the same as a plant without injury."
Right. I would say not. And what of this report from the US Congress, Office of Technology Assessment in 1989, linked to a couple of posts ago, which states
"When exposed to ozone, major annual crops produce reduced yields. Some tree species suffer injury to needles or leaves, lowered productivity, and in severe cases, INDIVIDUAL TREES CAN DIE."
"Western Pines and Associated Species
Miller and his colleagues were responsible for much of the early work on ponderosa and Jeffrey pines in the San Bernardino Mountains downwind of the smog-laden Los Angeles Air basin (Miller et al. 1963, Miller and Elderman 1977, Miller et al. 1982, Miller et al. 1989, Williams 1980). Fumigation studies with tree seedlings revealed O3 as the main cause of foliar injury manifested as chlorotic mottle and premature needle senescence. Current-year needles of ponderosa and Jeffrey pines become symptomatic when summer ozone exposure levels are high and soil moisture levels are favorable for ozone uptake through open stomata. Injury begins as the walls of the cell layer just below the epidermis degrade, causing the loss of cellular contents and a degradation of chlorophyll within the cells (Stolte 1996). The loss in chlorophyll beneath the epidermis appears on the needle surfaces as chlorotic blotches with diffuse borders that occur in no regular pattern, giving a yellow mottled appearance: hence the term chlorotic mottle. On ponderosa and Jeffrey pines, this foliar symptom indicates ozone pollution (Grulke and Lee 1997, Olson et al. 1992)."
"When ozone injury is severe, the disruption in biological processes in the needles eventually leads to accelerated needle loss, which leads in turn to a reduction in crown vigor, leaving the damaged pines more susceptible to secondary stress organisms. Researchers examined the relationships between ozone pollution and bark beetle attacks on ponderosa pines and found that trees with severe ozone injury suffered changes to the structure and chemistry of the phloem tissues, reducing the natural resistance of the trees to bark beetle attack (Cobb et al. 1968, Cobb and Stark 1970). Ozone does not kill trees, but it does weaken the host plants and leaves them vulnerable to aggressive infestation by bark beetles that do cause tree decline and mortality. Even in the absence of bark beetle attack, growth losses attributable to ozone pollution have been documented in both symptomatic and asymptomatic ponderosa and Jeffrey pines (Williams 1980)."
"The most ozone-sensitive ponderosa and Jeffrey pines have disappeared from the mixed conifer forest type of southern California, which is the only documented case where a tree-level effect induced by O3 on a particular forest type has resulted in a significant disturbance to the structure and function of the ecosystem. Over a 14-year study period, Miller and his colleagues were able to demonstrate that ozone-sensitive ponderosa and Jeffrey pines lost basal area in relation to other species more tolerant of ozone. The elimination of ozone-sensitive pines and the accumulation of ozone-tolerant species in the understory present a fuel ladder that puts the remaining overstory trees in increased danger in the event of a catastrophic fire. Further, the ozone-tolerant species are more susceptible to fire damage because of thinner bark and branches closer to the ground."
(There are several large chestnut trees around this house - this is what the leaves look like.)
"More recent studies on the sensitive pine forests in the San Bernardino Mountains have confirmed that average ambient ozone concentrations of 50-60 ppb are sufficient to cause foliar injury, reduced carbon fixation, and significant growth declines in bigcone Douglas-fir, as well as ponderosa and Jeffrey pines (Bytnerowicz and Grulke 1992, Peterson et al. 1991). The combined effects of prolonged drought and high ozone (Arbaugh et al. 1999) and O3 and high nitrogen deposition (Grulke and Balduman 1999) are contributing to growth disturbances in the forest that researchers believe may lead to the eventual replacement of pines by more nitrogen-tolerant and ozone-tolerant tree species (Arbaugh et al. 2003, Panek 2004) in the not too distant future. Other western species that have been tested for ozone sensitivity include western white pine and California black oak (foliar sensitivity), western hemlock (dry weight reduction), western redcedar (no effect), and giant sequoia (no effect)."
"Trembling Aspen and Aspen Clones
Aspen is another important and widely distributed tree species that is ozone sensitive (Karnosky 1976, 1989). Foliar injury symptoms on trembling aspen are visible as moderate to large, black, necrotic areas that extend across the leaf veins and are bifacial. Ozone exposure leads to accelerated physiological maturity and leaf senescence, decreased photosynthesis and chlorophyll, and adverse effects on growth such as root growth....
Under natural conditions, an ozone-induced reduction in root growth might be expected to make trees more susceptible to drought and nutrient deficiency (Greitner et al. 1994). Trees stressed by O3 are more susceptible to leaf rust fungi and a number of other foliar pathogens.
Ozone predisposes aspen to attacks by leaf rust fungi by altering the leaf surface waxes so that leaves are more wettable, thereby creating a microenvironment on the leaf surfaces that is favorable for fungal spore germination and subsequent infection by fungi (Karnosky et al. 2002, Percy et al. 2003b)."
"Duchelle et al. (1982) used charcoal-filtered and ambient air open-top chambers to study O3 effects on height growth of seven forest tree species native to the eastern U.S. After 2 years of exposure under natural field conditions, tulip-poplar and green ash seedlings exhibited growth
reductions of 44 and 77 percent respectively, while black locust, Virginia pine, eastern white pine, table mountain pine, and eastern hemlock seedlings showed a range in height growth loss of 13 to 23 percent. Similar adverse effects of O3 on tree growth have been reported for multi-year open-top field chamber studies with loblolly pine seedlings. Ozone-induced growth reductions of loblolly may occur with no visible evidence of needle injury or effects on pigment concentrations (Kress and Skelly 1982, Shafer and Heagle 1989)."
This analysis, indeed most, leave out the critical and imminent crash of the ecosystem. Emissions from burning fuel have rendered the atmosphere toxic to vegetation...and plants are the base of the food chain. Just as acidification is destroying coral reefs and calcium-based shell life in the ocean (which produces much of the oxygen we breathe) tropospheric ozone is killing trees and other plants that are the base of the terrestrial ecosystem.
The facts of ozone effects are well-established in reams of scientific studies. Ozone causes cancer, emphysema, asthma, and diabetes - all epidemics. Even worse, the inexorably rising concentration is causing crop losses, and has been shown to encourage insects, disease, fungus, and vulnerability to weather.
This is going to lead to massive food shortages that will diminish the population well before the effects of peak oil are manifested. We should determine the exact source of massive tree and plant decline, and then ration fuel, restricting its use to only the most essential purposes while we transition to clean forms of energy.
Anything less drastic is ecocide.
The battle rages on about those EPA standards, and its not some abstract political wrangle. It's our the survival of our species, and most others, at stake. Here is a link to an article in the Washington Post about Bush overriding an earlier EPA attempt to tighten regulations, which I found at the blog, Decarbonation. It gives a chilling sense of the machinations that accompany any attempt to thwart big fuel companies from unfettered burning and polluting. Unfortunately the legacy of the previous administrations continues to dominate agencies and politicians.
"It isn't often in Washington that a paper trail on a controversial regulatory decision leads back to the White House quite so publicly.
The conflict between Stephen L. Johnson, administrator of theEnvironmental Protection Agency, and Susan E. Dudley, head of regulatory review at the Office of Management and Budget, over how strong to make a standard on ozone, a component of smog, was unusual because President Bush was asked to break the impasse. He decided on a requirement weaker than what the EPA wanted.
"During my experience, the policy people in the administration are all part of the same administration and don't like to air a public policy dispute," said Donald R. Arbuckle, a retired deputy of the OMB Office of Information and Regulatory Affairs who served there 25 years.
Regulatory experts said this was the first time they recall a president stepping in, under a provision of an executive order allowing appeals between agencies and the OMB to be sent to him for a final decision. Typically, differences like these are worked out behind closed doors among top officials...
In the Bush administration, the OMB has usually intervened at earlier, informal stages of rulemaking, where there is no public documentation. That makes it difficult to know where changes in an agency's final rule originated.
Veterans of the process say the ozone dispute was extraordinary because three documents written between March 6 and March 12 spelled out in detail the policy positions and arguments that the OMB and EPA marshaled. The disagreement was over a so-called public welfare standard for ozone, which is designed to protect vegetation, parks and farm lands.
When the EPA sent its final rule to the OMB on Feb. 22, it proposed lowering the permissible ozone "public health" standard to 0.075 parts per million, the concentration in the air over an eight-hour period, from the current 0.084 parts per million.
The agency proposed for the first time changing the secondary standard to one in which ozone would be measured over a seasonal period because of concerns over the cumulative effect the pollutant has on vegetation.
Agricultural interests, including corn growers and others in the biofuels business, opposed the idea. They had a meeting with OMB officials, including Dudley, on Jan. 24. The administration reviewers also met with public health and environmental groups pushing to make the rule more stringent.
In going ahead with the plan for a separate secondary standard, Johnson was following the advice of EPA staff members and scientific advisers.
Dudley fired back in a March 6 memo to Johnson, signaling her opposition. "The draft rule under review does not contain a reasoned basis for concluding that a secondary standard set separate from the primary standard is 'requisite to protect the public welfare,' " she wrote.
The EPA responded the next day that "there is no presumption that the secondary standard should be the same as the primary standard." The agency said it was relying on new research to propose seasonal monitoring. The letter was signed by Marcus Peacock, the deputy administrator who once worked at the OMB review office. The EPA also prepared a "deliberative and confidential" memo on March 11 to support the new, separate standard.
It was then that the feud escalated to the president. Another letter from Dudley on March 12 said Bush concluded the two standards should be the same.
A senior administration official said the exchange of correspondence was included in the public record to demonstrate that no backroom deals had been made.
"We thought it would be in everyone's interest to show clearly what our concerns were and the rationale for those concerns," said the official, who spoke on condition of anonymity because the negotiations were confidential. The goal in posting the documents on government Web sites "was to minimize mischaracterizations of these concerns," the official said.
Johnson said at a news conference that he made the final decision on the rule, though the published preamble to the rule reflects the influence of the OMB and the White House.
Frank O'Donnell, president of Clean Air Watch, an environmental group in the District, said, "EPA was carefully trying to keep records to show [that the OMB] was pushing them in a different direction. They were squashed at the last minute."
Waxman's attempt to learn more about the rulemaking has been stymied so far. He has received only documents already made public, according to a follow-up letter he sent to Dudley on April 1. He said the committee is entitled to the material unless the president "intends to assert a valid claim of executive privilege."
Scientific Consensus on Air Pollution Impacts on Appalachian Forests
On March 26-27, 1999, fourteen scientists and experts with diverse specialties came together for a conference at Duke University's Nicholas School of the Environment, entitled "Acid Rain, Ozone and the Great Eastern Forests". They reviewed relevant literature, gave presentations of their own work, and engaged in scientific debate and discussion on the relationship between air pollution levels and the health of Appalachian forest ecosystems. Their conclusions, based on consensus, were presented to the public on the second day and are summarized here.
John Bachmann, EPA
Robert I. Bruck, North Carolina State University
Wade Davidson, University of Kentucky
Frank Gilliam, Marshall University
William Grant, NASA
Jillian Gregg, EPA
Orie L. Loucks, Miami University
Steve McNalty, US Forest Service
Niki Nicholas, Tennessee Valley Authority
Ram Oren, Duke University
Dan Richter, Duke University
William Sharpe, Penn State University
William Smith, Wake Forest University
David Weinstein, Cornell University
*****Summary of Consensus Findings********
"1) Forest Effects of Soil Acidification
In the late 20th century, many Appalachian highland soils are progressively being acidified by atmospheric deposition and by the regional regrowth of the eastern forest.
Acid deposition contributes significantly to soil chemistry, and accumulated over decades, can both increase (nitrogen and sulfur) and decrease (nutrient cations) the chemical elements in soils.
Soil acidification can be a predisposing stress contributing to the decline of forest plant species."
"2) Forest Effects of Ground-level Ozone ("smog")
Tree growth decreases under controlled ozone exposures for tree seedlings and saplings.
Ozone effects on trees are cumulative, thus exposures to even small concentrations can have an impact over time.
Reducing ozone levels to below ambient results in increased photosynthesis and growth in sensitive forest species.
The Appalachian forests will, most likely, change significantly if ozone levels remain the same, or increase.
3) Forest Effects of Nitrogen Saturation
A continuum of nitrogen saturation exists in the landscape, and the southern Appalachians represent an area where many factors leading to saturation come together.
Nitrogen enrichment appears to inhibit winter hardiness for conifers and possibly for hardwoods.
Nitrogen saturation affects trees through relative reduction of fine roots, which makes trees more susceptible to short term drought.
Nitrogen saturation increases trees' susceptibility to insects/disease."
(Certain lichens love nitrogen! Look at how it has spread on this crabapple - and how the bark is splitting and breaking off the trunk. Here it is on a tulip poplar.)
It's amazing how extensively the lichens have overtaken entire trees.
The lighter colored patches are where chunks of bark have fallen off.
"4) Air Pollution Effects on Forest Diseases and Pests
Both acute and chronic episodes of acid deposition, ozone, and nitrogen can alter the incidence, epidemiology, and magnitude of tree insects and pathogens."
"Experimental and field studies have shown insects and diseases can be proximal causes of forest decline but they are also as an outcome of precursor stresses, including atmospheric deposition.
Anthropogenic pollutant stress has been shown (in controlled experiments) to elicit plant biochemical and anatomical changes, leading to increased insect infestations and disease epidemics.
5) Summary Findings/Overview
Evidence exists that, for the high deposition regions of the Appalachians, acidification of the soils, ozone effects on trees, nitrogen enrichment, and potential insect and disease interactions with the above and other stressors, place the broadleaf ecosytems of the region on a path to change of probable public significance..."
Almost all of these pictures are from a radius of 5 miles around my home, in the past 2 weeks. This view is of a little unpaved country road.
I ventured into the woods and they are full of dying shrubs as well as trees,
Their leaves crisp and brown.
I dread wind now because when you see branches like this it means the roots are shriveled too, and won't anchor the tree to the land.
The trees over my neighbor's lovely barn are liable to crush it one of these days!
"More research, including long-term field studies and modeling, is urgently needed to fully understand the interactions involved in forest decline in the Appalachians."