Tuesday, December 8, 2009

Flower-fruit plants => Flying fauna! CO2, O2, N2

Green plants can't uptake carbon from soil, because they use water to move nutrients, water + carbon = carbonic acid (eats limestone -> caves). Soil fungi do decompose carbs, as do animals, and exude CO2. Plant leaves "breathe" O2 just like animals and fungi. Plant leaves "eat" CO2, using solar energy to decompose it into O2 & C, the C is then combined with H et al to make carbs for plant tissue. Plants (grasses) require wind to reduce stratification of gases (gas stratification starves them of C or chokes them of O2), tropical rainforests need mobile animals not only for fruit dissemination but also gas mixing (flying insects/fruit bats/fruit birds), this is the major advantage of angiosperm flora over non-fruiting gymnosperms (seeded but non-fruiting conifers) and the reason that flowering plants and symbiotic fauna "won" the competitive war against cycads, conifers, ferns, etc. Biological textbooks say little about gas stratification prevention, but it is critical in closed-canopy ecosystems (same reason that sealife comes in both mobile jetsam (tail/fin) & immobile photosynthetic flotsam). [my comment@]
flowers + fruit induce faunal flight to mix gas

flower origin
ancient scorpionflies pollinating gymnosperms?

"The first flowering plants evolved more than a hundred million years ago, while dinosaurs were still on the scene. Since then, they’ve come to dominate the world, largely outcompeting the plants that were there before, such as conifers, cycads, and ginkgoes...The reason for showy flowers is to attract pollinators, most commonly insects. Today, the majority of flowering plants use insects to carry their pollen, whereas most gymnosperms (the older group of plants, including conifers) are pollinated by the wind. Insects have one clear advantage over the wind: they can track down another flower of the same species...From insect fossils, it looks like there were pollinators (scorpionflies) around in the Jurassic, which had evolved together with the gymnosperms that were around at the time...some fossil gymnosperms weren't well adapted for wind pollination."

"Nitrogen makes up nearly 80% of the atmosphere, but pure nitrogen (aka N2) isn’t very easy to get at. What counts is ‘reactive nitrogen’, especially dissolved nitrate (NO3-) and ammonia (NH4+). Plants can readily take this up and use it, helping them to grow faster (NPK fert). In fact, over half of the reactive nitrogen being made each year now comes from human activities.
Ecologists know quite well that adding nitrogen often leads to fewer species living together. And a recent experiment neatly showed why that might be: when plants’ roots are battling it out for nutrients (like nitrogen), it’s a relatively fair fight. But add nitrogen, and the fight moves above the ground, for the light plants need to grow. Here, bigger plants can quickly shade out smaller ones and kill (some of) them off... carbon dioxide and nitrogen have different effects on plants, and they seem to balance out to some extent. Although the effect of light wasn’t clear cut in this experiment, I think it might also be important that higher carbon dioxide lets plants grow in deeper shade."
leaf veins

"...primitive ancestors of the tyrannical angiosperms underwent adaptation to feed on the then abundant atmospheric carbon dioxide. Through undertaking a process known as photosynthesis, some early plant-forms gained reproductive advantage and quickly out-competed their rivals. In time, their numbers became so great that oxygen – a byproduct of photosynthesis - accumulated in the biosphere to such extent that it triggered a catastrophic transition to an oxygenated planet. In hindsight, this rapid transition, called the ‘Great Oxygenation Event,’ can be viewed as a first step in the angiosperms’ selfish remaking of the Earth, and as foreshadowing the eventual enslavement of all humankind.

Initially, constrained anatomy affectively limited the plants’ ability to channel the xylem tissues required for harnessing the sun’s rays. Xylem tissues are essential to photosynthesis because it is their job to convey water and nutrients throughout the plant. Early plants lacked sufficient internal structure and architecture to serve as pathways for xylem transport; this physically restricted the amount of energy that could be generated through photosynthesis. In other words, because of a lack of adequate venation, the radiation of angiosperms was kept in-check. However, this all changed during the Cretaceous Period.

Over the course of evolutionary history, natural selection tinkered at the physiology of the angiosperms, incrementally improving their clumsy and inefficient application of photosynthesis until eventually, about 120,000,000 years ago, the density of the angiosperms’ veins dramatically increased by 300-400%. The upsurge in venation meant that the plants’ xylem tissues more frequently made contact with individual plant cells; this pushed the capacity of the angiosperms’ energetic processes far beyond what they could achieve previously. Newly acquired energy surpluses were promptly invested in reproduction and as a result angiosperm populations exploded the world over."

Marine CO2 effects on shellfish, crustaceans, calcific algae:
crabs & CO2
(compare to green plants in soil which can't absorb carbonic acid through roots, so must consume CO2 in air via photosynthesis.)
eco-web-tet: ants, fungi, bacteria, plant in 4 way symbiotic relationship
plants & ants

Game theory: bacteria and human in decision making in stress

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