User:Blueflamelord/sandbox

Close-up of the amount of sunlight coming through an individual corn leaf

Bio-geoengineering is a form of climate engineering which seeks to increase the solar reflectivity (or albedo) of crops by modifying physiological leaf and/or canopy traits to help reduce regional surface warming.

Crop Albedo Modification

Bio-geoengineering relies on the manipulation of crop attributes, such as through selective plant breeding or genetic engineering, to increase a crop's net albedo. Although there are noticeable differences in albedo between distinct crop types, bio-geoengineering mainly focuses on intra crop modification and substitution, which inherently limits its overall albedo change, but the changes are much easier to be implemented.

The net albedo of a set of crops can be broken down into two contributing layers: the reflectivity of individual crop leaves and the overall canopy's effective albedo due to position, angle, and coverage of leaves.

Leaf Glossiness

At the individual leaf level, the base amount of light reflected by a given leaf depends largely on the type of crop and the wavelength of light you are concerned with. It is possible to alter a crop leaf's net (or specific wavelength) reflectivity either through selective breeding and/or genetic engineering, or through applying a sort of reflective spray (potentially alongside pre-existing pesticides) directly to the leaves.

For the visible light part of the electromagnetic spectrum, plant stress has been found to directly correlate to increased reflectivity of certain visible wavelengths. However, when you average over the entire visible spectrum with larger chlorophyll contents, it has been found that there is a strong positive relationship between plant chlorophyll content and reflectivity.

As for near infrared wavelengths, which contribute about 50% of the total solar radiation energy at sea level, there is a negative relationship between plant hydration and reflectivity. This, on top of the fact that this effect is less prominent at the canopy level, makes it unlikely that reflectivity of near infrared wavelengths will be modified for the purposes of bio-geoengineering.

Canopy Morphology

When attempting to modify the net albedo of crops on a larger scale (ex. a field of crops or, as would be required to achieve any significant amount of global cooling, entire regions of the world), the varying morphological traits of crop canopies contributes far more than the differences in reflectivity of individual crop leaves. When sunlight shines down on a field of crops, some of it will hit and reflect off of the crops (and in most cases their leaves), while the rest of the reflected light will be from the background soil. Thus the overall reflectivity of a crop canopy is largely dependent on the orientation, angle, and placement of the leaves (which can be measured by the leaf area index and leaf angle distribution), as well as the albedo of the background soil.

Advantages

Because of its inherently low invasiveness (especially in terms of land use change and pre-existing food production systems) compared to other forms of geoengineering, bio-geoengineering has been argued to offer multiple advantages and much fewer risks. One advantage is the fact that pre-existing infrastructure is already adequate in propagating these specific traits to large-scale crop cultivations. Another is that for specifically food crops, which make up the vast majority of arable crops, an annual system of replanting modified crop varieties already exists in order to keep up with the modern science in designing plants to be more resistant to negative external factors (in order to achieve higher yield and quality), which makes the process of automatically introducing a new crop variety very much doable, even at a large scale.

Concerns

On certain parts of the electromagnetic spectrum, the absorptance of crop leaves is sometimes directly tied to the overall healthiness and yield of said crop, so there must be a balancing act between maximizing reflectivity of individual leaves while ensuring it does not negatively impact overall crop production.

References

Category:Agriculture Category:Biological engineering Category:Climate engineering

Article Evaluation:

Evaluating Content

Almost the entire article, whether it be the "Introduction," "Bio-geoengineering solutions to climate change," or "Downside of bio-geoengineering" sections only focusing on broad geoengineering topics rather than specifically biological ones, and give very little information not already found in the climate engineering (aka geoengineering) Wikipedia page. This article could be very much improved by shifting the focus away from just geoengineering, which already has its own article, to specifically the biological forms of geoengineering, as that is what the article is supposed to be about. Specifically, explaining bi-geoengineering and how it is linked to and distinct from overall geoengineering and creating sections with explanations, uses, and downsides for the most prominently used forms of bio-geoengineering (and maybe include the lesser used ones at the end) would be incredibly useful. On top of this all, the information presented in this article is largely disjointed, irrelevant to the topic, and unorganized, plus only the beginning description section has any links to other articles, all of which are decent, but more could definitely be included.

Evaluating Tone

This article, especially the wording in the sections beyond the initial article description, have a very clear bias towards a more fatalistic view of climate change, such as claiming that the lowest possible change in global temperatures is 3 degrees Celsius and statements like "If we are not able to sustain such technology many wildlife can possibly die due to the rapid change in the earth's climate."

Evaluating Sources

There are quite a few useful citations/references given (including various scientific papers, articles, and journals), although a lot of the information within them are either not used, used incorrectly, or misinterpreted. While almost all of the information/facts given in the Wikipedia page are properly referenced and come from mostly neutral sources, they are either presented in a bias manner, or cherry picked to contain less relevant or undetailed information.

Evaluating Talk Page

No conversations at all have been had on this article's talk page, but it is labelled as 'Low Importance' and 'Start Class' for three different WikiProjects: Environment, Climate Change, and Biology