BIOMIMICRY PRECEDENT

My concept involves appreciating the natural elements of the site and enhancing these. In order to fully appreciate nature is appreciating it's natural processes. The natural elements on site are vegetation (various plants) and water. I want my building to incorporate these elements in the building design and processes. By including these elements into my design, it adds another layer of appreciation and understanding of these elements, expressing them in a different way. The building will be an appreciation of these elements by using their processes and expressing how these function. The building itself will be an exhibition of natural processes.

Biologist and writer Janine Benyus notes that nature and natural processes follow 9 basic principles:

1. Nature runs on sunlight
2. Nature uses only the energy it needs
3. Nature fits form to function
4. Nature recycles everything
5. Nature rewards cooperation
6. Nature banks on diversity
7. Nature demands local expertise
8. Nature curbs excess form within
9. Nature taps the power of limits

SOURCE: http://greenopolis.com/goblog/joe-laur/9-ways-be-smart-leaf-biomimicry-learning-conservation-and-recycling-nature

The building will function as part of the landscape by mimicking its processes and systems. I am particularly interested in the vegetation, seeing as my proposal includes an urban park. That is why I have chosen to use the function of a tree and it's leaves as my biomimicry precedents.

Trees/leaves have various characteristics and process that can be translated into built form and building technology:

• Self-cleaning (shape and texture)
• Water repellent to keep occupants dry
• Absorb sunlight for energy
• Leaf veination system for circulation and ventilation
• Water storage system (vacuoles)
• Colour changing in different conditions ie. when there is not water (dry weather) they turn brown - interactive facade
• Lightweight structure
• Large surface area to maximise exposure to the elements

A bit more information about some of these processes:

SELF CLEANING:

"Water has two major forces acting on it at the same time: its attraction to itself (which causes it to ball up) and adhesive forces (which cause it to stick to surfaces, pulling it down). Adhesive forces on water tend to be maximized on smooth surfaces, because the liquid-to-solid contact area is large. But because water and air are much less naturally adhesive than water and solids, roughened surfaces of certain microstructure tend to reduce adhesive force on water droplets, as trapped air in the interstitial spaces of the roughened surface result in a reduced liquid-to-solid contact area. This allows water's self-attraction to be expressed more fully, leading it to form a sphere."

"At the same time, due again to natural adhesion between water and solids, dirt particles on a leaf's surface stick to the water, like a rolled snowball that picks up leaves from your lawn. Since a ball rolls more easily than a flattened bump, the role of gravity now becomes significant: the slightest angle in the surface of the leaf (e.g., caused by a passing breeze) causes balls of water to roll off the leaf surface, carrying away the attached dirt particles - without the leaf having to expend any energy or use any harmful chemical detergents."

SOURCE: http://www.biomimicryinstitute.org/case-studies/how-nature-cleans.html

COLOUR CHANGE:

"Color changing plants need three things to survive and grow. The first is water which they absorb through their roots. The next necessity for a plant to survive is carbon dioxide which they absorb from the air much like we breathe in oxygen from the air. The third and final component is sunlight which plants use as a source of energy to convert the water and carbon dioxide into Glucose, a kind of sugar, which plants need to grow. Ultimately, the glucose is the food and the water, carbon dioxide and sunlight are the materials the plant needs to make that food."

"[It is] the leaves of a tree that turn sunlight into the needed energy to power their glucose manufacturing plant in a process known as photosynthesis. One of the chemicals that aids in the process of photosynthesis is chlorophyll. It’s also responsible for the green color common to leaves."

"As the days grow shorter and the nights grow longer, there’s a net loss of efficiency in a plant’s ability to photosynthesise. Basically, there’s just not enough light to effectively power the factory to make the glucose. Ultimately, the energy required to feed and maintain leaves that aren’t doing the tree much good in the winter is simply not worth the effort. The leaves are also vulnerable to freezing temperatures. Rather than work hard and expend energy to maintain low producing element, the tree is better off shedding its leaves and feeding on stored energy sources until the days grow longer again."

SOURCE: http://www.howdowhy.com/why-do-leaves-change-color-and-where-do-the-colors-come-from/

VEIN CIRCULATION:

Closed loop system - Leaf veination is used to transport water to all parts of the leaf. The big dot is a damage in the network e.g. where an insect has eaten. However, due to this network the flow isn't stopped, and can go everywhere in the network. This could be translated to building terms where the holes could be an obstruction or diversion in a pathway, and with a circulation system that follows a closed loop, the user may still continue on their journey.

SOURCE:http://www.treehugger.com/files/2010/03/biomimicry-leaf-veins-distribution-networks-electricity-water.php

LEAF FUNCTION:
"Leaves are the powerhouse of plants. In most plants, leaves are the major site of food production for the plant. Structures within a leaf convert the energy in sunlight into chemical energy that the plant can use as food. Chlorophyll is the molecule in leaves that uses the energy in sunlight to turn water (H₂O) and carbon dioxide gas (CO₂) into sugar and oxygen gas (O₂). This process is called photosynthesis."

LEAF STRUCTURE:
"A leaf is made of many layers that are sandwiched between two layers of tough skin cells (called the epidermis). The epidermis also secretes a waxy substance called the cuticle. These layers protect the leaf from insects, bacteria, and other pests. Among the epidermal cells are pairs of sausage-shaped guard cells. Each pair of guard cells forms a pore (called stoma; the plural is stomata). Gases enter and exit the leaf through the stomata.

Most food production takes place in elongated cells called palisade mesophyll. Gas exchange occurs in the air spaces between the oddly-shaped cells of the spongy mesophyll.

Veins support the leaf and are filled with vessels that transport food, water, and minerals to the plant."

LEAF FORMS:
"Leaves come in many sizes and shapes; they are often used to help identify plants. Some leaves are flat and wide; others are spiky and thin. Plant spines (like cactus spines) are actually modified leaves."

LEAF GLOSSARY:

• air space - intercellular gaps within the spongy mesophyll. These gaps are filled with gas that the plant uses (carbon dioxide - CO₂ ) and gases that the plant is expelling (oxygen - O₂, and water vapor).
• chlorophyll - a molecule in leaves that can use light energy from sunlight to turn water and carbon dioxide gas into sugar and oxygen (this process is called photosynthesis). Chlorophyll is magnesium-based and is green.
• cuticle - the waxy, water-repelling layer on the outer surface of a leaf that helps keep it from dying out (and protect it from invading bacteria, insects, and fungi). The cuticle is secreted by the epidermis (including the guard cells) and is often thinner on the underside of leaves. The cuticle is generally thicker on plants that live in dry environments.
• epidermis - the protective, outler layer of cells on the surface of a leaf. The guard cells (and stoma) are part of the epidermis. The surface of many leaves is coated with a waxy cuticle which is secreted by the epidermis.
• guard cell - one of a pair of sausage-shaped cells that surround a stoma (a pore in a leaf). Guard cells change shape (as light and humidity change), causing the stoma to open and close.
• mesophyll - the chlorophyll-containing leaf tissue located between the upper and lower epidermis. These cells convert sunlight into usable chemical energy for the plant.
• palisade mesophyll - a layer of elongated cells located under the upper epidermis. These cells contain most of the leaf's chlorophyll, converting sunlight into usable chemical energy for the plant.
• petiole - a leaf stalk; it attaches the leaf to the plant.
• photosynthesis - the process in which plants convert sunlight, water, and carbon dioxide into food energy (sugars and starches), oxygen and water. Chlorophyll or closely-related pigments (substances that color the plant) are essential to the photosynthetic process.
• spongy mesophyll - the layer below the palisade mesophyll; it has irregularly-shaped cells with many air spaces between the cells. These cells contain some chlorophyll. The spongy mesophyll cells communicate with the guard cells (stomata), causing them to open or close, depending on the concentration of gases.
• stem - (also called the axis) the main support of the plant.
• stoma - (plural stomata) a pore (or opening) in a plant's leaves where water vapor and other gases leave and enter the plant. Stomata are formed by two guard cells that regulate the opening and closing of the pore. Generally, many more stomata are on the bottom of a leaf than on the top.
• vein (vascular bundle) - Veins provide support for the leaf and transport both water and minerals (via xylem) and food energy (via phloem) through the leaf and on to the rest of the plant.

SOURCE: http://www.enchantedlearning.com/subjects/plants/leaf/

LEAF STRUCTURE

• The upper cuticle is thicker than the lower cuticle to resist dehydration due to the sun's heat, also to absorb rain from above.
• Leaves are usually thin so that water can reach the inner cells easily
• Leaves are usually broad and flat to absorb as much light as possible
• Veins bring in water and carry away product of photosynthesis

Leaf layers

SOURCE:http://www.biotopics.co.uk/plants/leafst.html