Saturday, September 17, 2016
Note: This program first aired September 17, 2016.
Our bodies are over 60% percent water. We can only live a matter of days without water. Water covers 71% of the surface of this planet.
It should be no surprise that people attempting to live according to traditional, earth centered, non western value systems hold water to be sacred. Call them Indians, native peoples, first nation, aboriginal, tribal, many of these communities still hold to ideals that see water as the sacred blood of the earth, as the first medicine. And so it should be—all life depends on access to clean water.
Water is a polar molecule, making it a wonderful solvent, readily dissolving any substance that has an atomic electrical charge. Liquid water is fluid, and can easily transport any other fluid substance in it, even if that substance is non polar, having no electrical charge, and can’t dissolve in the water. Even if that substance is crude oil.
Crude oil is made up of a mixture of many different fractions of hydrocarbons, ranging from the heavy end with things like asphalt and paraffin, to the light end with things like the methane and propane, some of the constituents of natural gas. Crude oil contains other substances, related to the hydrocarbons we burn in our cars and furnaces, things you might have experimented with in organic chemistry class, like the aromatics benzene, toluene, and xylene. And even though the aromatics come from crude oil, something we typically think of as insoluble in water, these light fractions are soluble in water. They also have a low atomic weight, so they evaporate into the air quite readily as well. And worst of all, they are carcinogenic.
This is the kind of thing you think about when you learn that an oil transporting pipeline is about to be built through a river that is your source of drinking water. You think about the pipeline leaking, and the heavy fraction of the crude oil, being denser than freshwater, sinking to the bottom of the river, virtually impossible to clean up, and the lighter more soluble fractions traveling with the water to be taken up by municipal water systems down stream. You think about how common it is for pipelines to break, and in isolated rural areas how long it takes for people to notice.
These are the things I was thinking about as I stood in the rain attending a solidarity event for the Standing Rock Sioux tribe in North Dakota. The Standing Rock tribe has been protesting the fast track approval of the Dakota Access pipeline, its permitted path through off reservation sacred sites, and its crossing of the Missouri River, the drinking water source for the tribe and rural farmers and ranchers downstream. Native tribes from all over north America have been converging on the protest encampment at the Sioux reservation in a show of solidarity, and events like the one I attended, organized by Wabenaki leaders here in Maine, are popping up nationwide. You don’t have to be Native American to understand that water is sacred, though watching the Wabenaki prayer ceremonies made me realize that I lost the language of sacred connection many generations ago. Nor do you have to be a scientist to understand the linkage of water pollution and illness, and unfortunately I speak that language all too fluently.
Water is not unique in the universe, in fact the only reason we have it hear on Earth is that it came here the same way all the other matter on Earth did, as an aggregation of space dust and rocks. But water is what makes this planet unique, and what makes life possible on this third rock from the sun. The Standing Rock Sioux know it, and so do you.
Yep, pipelines do leak into rivers: https://usresponserestoration.wordpress.com/2014/06/20/as-oil-sands-production-rises-what-should-we-expect-at-diluted-bitumen-dilbit-spills/
People say these pipelines don’t leak. Really? http://www.npr.org/sections/thetwo-way/2016/07/25/487357502/canadian-oil-spill-threatens-drinking-water
Another one: http://news.nationalgeographic.com/news/energy/2015/01/150120-oil-spills-into-yellowstone-river/
A map of the pipelines: https://www.propublica.org/article/pipelines-explained-how-safe-are-americas-2.5-million-miles-of-pipelines
Saturday, September 3, 2016
Note: This program first aired on September 3, 2016.
Last week we talked about fungus, and they ways it makes a living in this world. The mushrooms we see in the forest are just the tip of the fungal iceberg, the vast majority of fungal biomass in the forest is subterranean. These are the bundles of fungal fiber called mycelium, and if the mushroom’s job is reproduction of the fungus, the mycelium’s job is to nourish it.
There are three ways that fungi can get food from the environment; they can parasitize another fungus*, they can decay organic matter, or it can form a relationship with a plant in an “I’ll scratch your back if you scratch mine” symbiosis called mutalism. We covered parasitism and saprotrophism earlier, leaving mutalism for today.
It turns out that many of those mushrooms you see erupting from the forest floor are from fungal biomass that is in direct relationship with the trees that make up that forest. The individual hyphal filaments that make up the mycelium, or all that fungal biomass beneath the surface of the soil, get up close and personal with the tiny root hairs, or rootlets from the tree and form what is called a mycorrhizal relationship, “myco” referring to fungus, and “rrhizal” referring to roots. Trees and their fungus typically form what is called an ectomycorrhizal relationship—meaning the fungus only just barely infiltrates the upper layers of the rootlet tissue, squeezing in between the cells of the root outer cortex, forming a sheath. The conjoining of the tree roots with the fungal mycelium effectively expands the tree’s root system by orders of magnitude, and even directly connects it to other trees of its species if the mycelium forms an ectomycorrhizal relationship with more than one individual.
Typically a fungal species has only one suitable tree species it can pair with, though often trees can have many different fungal partners. Many of the trees I see daily are obligated to form relationships with fungal partners; they cannot grow without the assistance of the fungus. Those groups include pines, oak, beech and spruce. Other tree species are facultative, and can grow without a fungal partner but grow better with one. Examples include maples, juniper, willows and elms.
I said this is an I’ll scratch your back if you scratch mine kind of situation, both partners benefit from this trans species contact. As I noted, the tree gets a major extension of its root system, gaining what one source called “hundreds of thousands of kilometers’ of individual hyphae, collecting water and inorganic nutrients from the soil. Essential nutrients like phosphorous and nitrogen are limited in the terrestrial environment, and the fungus is able to aggregate these and make them more available to the tree than they would be otherwise. The fungus also is able to collect water from the soil, though there can also be instances when the plant gives moisture to the fungus as well. And in some cases the fungus produces plant growth hormones, stimulating tree root growth. What we know for sure the fungus gets out of the relationship is carbon, in the form of sugar. 10 to 15 % of the carbon fixed by the tree gets channeled to the mycorrhizal partner. Both players are able to trade something they are good at getting from the environment for something they need, to the benefit of everyone.
This kind of relationship isn’t limited to trees and mushrooms. Many herbaceous plants and agricultural crops form mycorrhizal relationships as well, relationships characterized by even deeper infiltration of the fungus into the plant tissue. And in a totally different part of the world, coral reefs, we see the mutualistic symbiosis of coral polyps and photosynthetic plankton, swapping carbon in the form of sugar in return for inorganic nutrients. In a great example of convergent evolution, many realms of life species have evolved to swap resources in order to increase their competitive fitness. That is the cool thing about evolution, when something works, it keeps popping up independently on the tree of life.
So many of those mushrooms you see in the woods this fall, are part of a legacy of remarkable biological cooperation.
* or plants or even animals!