Researchers Develop "Biological Concrete" for Moss Covered Walls

Scientists at a Spanish university are developing a new type of concrete that captures rainwater to create living walls of moss and fungi. Unlike existing vertical garden systems which require complex supporting structures, the new "biological concrete" supports the growth of organisms on its own surface, according to researchers from Universitat Politècnica de Catalunya in Barcelona.

The concrete contains a biological layer that collects and stores rainwater, providing a moist growing environment where microalgae, fungi, lichens and mosses can thrive, they explain in a report. A waterproof layer separates the organisms from the inner structural part of the concrete, while an outer layer acts in reverse, allowing rainwater in and preventing it from escaping.

The concrete also absorbs carbon dioxide in the atmosphere and acts as an insulating material and a thermal regulator, say the researchers, who are currently in the process of patenting the material. The next step is to accelerate the process so that the mossy surface develops in under a year, they add.

Researchers at the UPC develop a biological concrete for constructing “living” façades with lichens, mosses and other microorganisms

The Structural Technology Group has developed and patented a type of biological concrete that supports the natural, accelerated growth of pigmented organisms. The material, which has been designed for the façades of buildings or other constructions in Mediterranean climates, offers environmental, thermal and aesthetic advantages over other similar construction solutions. In studying this concrete, the researchers at the Structural Technology Group of the Universitat Politècnica de Catalunya · BarcelonaTech (UPC) have focused on two cement-based materials. The first of these is conventional carbonated concrete (based on Portland cement), with which they can obtain a material with a pH of around 8. The second material is manufactured with a magnesium phosphate cement (MPC), a hydraulic conglomerate that does not require any treatment to reduce its pH, since it is slightly acidic.

On account of its quick setting properties, magnesium phosphate cement has been used in the past as a repair material. It has also been employed as a biocement in the field of medicine and dentistry, indicating that it does not have an additional environmental impact. The innovative feature of this new (vertical multilayer) concrete is that it acts as a natural biological support for the growth and development of certain biological organisms, to be specific, certain families of microalgae, fungi, lichens and mosses.

Having patented the idea, the team is investigating the best way to promote the accelerated growth of these types of organisms on the concrete. The goal of the research is to succeed in accelerating the natural colonisation process so that the surface acquires an attractive appearance in less than a year. A further aim is that the appearance of the façades constructed with the new material should evolve over time, showing changes of colour according to the time of year and the predominant families of organisms. On these kinds of buildings, other types of vegetation are prevented from appearing, lest their roots damage construction elements.

Three layers of material

In order to obtain the biological concrete, besides the pH, other parameters that influence the bioreceptivity of the material have been modified, such as porosity and surface roughness. The result obtained is a multilayer element in the form of a panel which, in addition to a structural layer, consists of three other layers: the first of these is a waterproofing layer situated on top of the structural layer, protecting the latter from possible damage caused by water seeping through. The next layer is the biological layer, which supports colonisation and allows water to accumulate inside it. It acts as an internal microstructure, aiding retention and expelling moisture; since it has the capacity to capture and store rainwater, this layer facilitates the development of biological organisms. The final layer is a discontinuous coating layer with a reverse waterproofing function. This layer permits the entry of rainwater and prevents it from escaping; in this way, the outflow of water is redirected to where it is aimed to obtain biological growth.

CO2 reduction

The new material, which has various applications, offers environmental, thermal and aesthetic advantages, according to the research team led by Antonio Aguado and supported by Ignacio Segura and Sandra Manso. From an environmental perspective, the new concrete absorbs and therefore reduces atmospheric CO2, thanks to its biological coating.

At the same time, it has the capacity to capture solar radiation, making it possible to regulate thermal conductivity inside the buildings depending on the temperature reached. The biological concrete acts not only as an insulating material and a thermal regulator, but also as an ornamental alternative, since it can be used to decorate the façade of buildings or the surface of constructions with different finishes and shades of colour; it has been designed for the colonisation of certain areas with a variety of colours, without the need to cover an entire surface. The idea is to create a patina in the form of a biological covering or a “living” painting. There are also possibilities for its use in garden areas as a decorative element and as a sustainable means of blending buildings and constructions into the landscape.

Architectural renovation

The material lends itself to a new concept of vertical garden, not only for newly built constructions, but also for the renovation of existing buildings. Unlike the current vegetated façade and vertical garden systems, the new material supports biological growth on its own surface; therefore, complex supporting structures are not required, and it is possible to choose the area of the façade to which the biological growth is to be applied.

Vegetated façades and vertical gardens depend on a plant substrate in some type of container, or they use cultures that are totally substrate-independent, such as hydroponic cultures. However, they require complex systems attached to the construction itself (layers of material) and even adjacent structures made of metal or plastic. This can lead to complications associated with additional loads, the reduction of light, or the reduction of space around the building. With the new “green” concrete, the organisms can grow directly on the multi-layered material.

Patent and commercialisation

The research has led to a doctoral thesis, which Sandra Manso is writing. At present, the experimental campaign corresponding to the phase of biological growth is being conducted, and this will be completed at the UPC and the University of Ghent (Belgium). This research has received support from Antonio Gómez Bolea, a lecturer in the Faculty of Biology at the University of Barcelona, who has made contributions in the field of biological growth on construction materials. At present, a patent is in the process of being obtained for this innovative product, and the Catalan company ESCOFET 1886 S.A., a manufacturer of concrete panels for architectural and urban furniture purposes, has already shown an interest in commercialising the material.

Read more http://www.dezeen.com/2013/01/03/spanish-researchers-develop-biological-concrete-for-moss-covered-walls/

The Green Wave: Sink or Swim

“The goal of life is living in agreement with nature.”

Zeno (335 BC-264 BC)

Sustainability is on the minds of every industry as the green movement has reached a critical mass. In the short time frame of fifteen years, green architecture and sustainable technologies have evolved from a radical fringe of ardent supporters to a generally accepted public mandate that is revolutionizing the entire world economy. Below the surface is a monumental shift in corporate thinking which is refining this brave new green world. Every industry will be challenged to make the shift to a new paradigm in order to prosper or even survive. The landscape and nursery industry has always been in the center of the green movement, but is not generally perceived as a leader which consistently brings innovation to the table. There can be no denying the magnitude of the sustainability movement as it becomes increasing codified in our daily life. The time is fast approaching for the landscape and nursery industry to assess its future and decide to either sink or swim in the mounting green wave. The commitment to become leaders in the sustainability movement will require dedication and innovation from both individual businesses as well as trade organizations.

The first question that arises is “what does it mean to be green?” Unfortunately, there are no publicly established policies or guidelines which are definitive, but rather a series of sometimes vague and confusing principals. Being green is easiest described as a way of thinking, in that every action shall do no wrong or diminish the earth’s resources for future generations. The difficult part is that every industry will be required to define these sustainable principals for their specific industry. Be assured that this process will not be simple and the rules will constantly change, but every industry will struggle in defining its role in the new green economy.

The origins of this green tidal wave can be traced back to a single document. In 1992, the City of Hanover, Germany hired architect William McDonough to craft a series of environmental principals to guide architects and planners in the development of exhibits for the 2000 World Expo to be held in Hanover. This short list of environmental goals came to be known as the Hanover Principals. Although over the years these sustainable principals have been expanded, interpreted, defined and debated, they are still the fundamental foundation of the sustainability movement.

As other industries begin to define their role in sustainability, they contribute useful tools which can help the landscape and nursery industry to find its way. Places to look for current thinking and valuable information include the United States Green Building Council (USGBC) www.usgbc.org, which has established the Leadership in Energy and Environmental Design (LEED) green building rating system. The American Society of Landscape Architects (ASLA) www.asla.org has established a strategic partnership with a number of environmental organizations called the Sustainable Site Initiative www.sustainablesites.org to establish a green site rating system for individual sites. There are a number of organizations such as “Cradle to Cradle Certification” www.mbdc.com/certified.html, which helps customers purchase and specify products that are pursuing a broader definition of quality environmentally-intelligent design. Industry specific guides are emerging such as the Certified Forest Products Council (CFPC) www.certifiedwood.org which provides information about sustainable forestry, and includes a directory of sustainably harvested lumber.

Although these organizations provide some insight in how sustainability is interrupted by other associations, none of the documents will address in detail the needs for the landscape and nursery industry. This will come from within the industry as we begin to look critically at the opportunities for changing traditional practices and replacing them with more environmentally friendly business practices. The initial areas for consideration are easy to identify such as business practices that negatively impact air quality, water quality, biodiversity and consumption of natural resources. Let’s look at each of these four simple opportunities in more detail as they might relate to traditional industry practices, knowing that there are dozens of other subjects that should be considered in mainstreaming sustainability into every aspect of the landscape and nursery industry.

Air Quality

With the emissions from operating and refueling of landscape equipment, vehicles have a significant impact on air quality. Small gasoline-powered engines often produce much greater levels of pollution than that of a full sized car per hour of operation. The estimates can be as much as 1000 times more emissions are produced from small gasoline-powered engines. When these engines are mistuned, or run without air filters, measurements show as much as 50% of the fuel exhausted as unburned hydrocarbons. The EPA estimates that as much as 5% of urban air pollution can be linked to their usage. Considering the entire carbon footprint of the landscape and nursery industry, the consequences are significant.

A sustainable approach would minimize air pollution by investing in hybrid or fossil free vehicle fleets as well as a mileage optimization on how those fleets are deployed each day. Small gas-powered engines can be replaced with electric powered equipment. While electric still has environmental impacts primarily in the manufacturing process, the total embodied energy used during the equipment’s life cycle cost is much less. The most environmentally friendly grounds maintenance equipment is human powered which does not rely on a power source. I believe there could be an emerging niche in the market for a premium priced high sustainability ground maintenance service.

Water Quality

The landscape and nursery industry applies a vast amount of chemical based pesticides and fertilizers which, even with the best management practices, are subject to leaching into stream ways and water courses. While monumental progress has been made in training grounds staff in the proper calibration and application of the chemicals, it does illustrate the industry’s reliance on preventative chemical use instead of prescriptive treatment of diseases. An enlightened chemical approach which reduces generic broad based preventative treatments in favor of selective targeted solutions would shift the chemical industry’s investment toward development of new softer solutions. A serious discussion in the landscape industry needs to challenge the reliance on traditional chemical approaches and foster greater acceptance of ecological based approaches.

The greatest impact the landscape and nursery industry has on water quality is in the management of construction activities through the primary responsibility for erosion control. Our experience indicates the landscape industry is only marginally engaged in erosion control. No other trade has a greater opportunity to express leadership in managing water quality during site grading and establishment of vegetation. This industry should be the foremost advocate and expert in site erosion control implementation. Accepting responsibility for the site can expand revenues for forward thinking companies.

With the increased development of suburban areas, more frequent and pronounced flooding has occured. This not only results in erosion, stream pollution, and destruction of aquatic habitat, but tremendous property damage and loss of human lives. Several compelling best management practices exist that the industry can use to help to reduce flooding and reuse a precious natural resource. These stormwater based solutions such as rain harvesting, rain gardens, green roofs and bioswales, while not new have garnered a new wave of public interest. The best thing about these stormwater technologies is that they easily fall into the traditional market of the industry. A concerted effort in promoting integrated stormwater solutions within the industry would represent another leadership position the industry could assume.

Declining Biodiversity

The world's biodiversity is declining at an unprecedented rate, with current extinction rates that are at least 900 times higher than natural rates found in the fossil record. Over 15,000 plant and animal species are now considered at risk of extinction representing an increase of 3,330 species since 2003. The landscape and nursery industry may contribute more to declining biodiversity than it does in preventing it. Consider the impacts of introduction of invasive plants into the landscape, clearing land, establishment of lawns, planting too few species that benefit wildlife, overuse of pesticides and dominant use of limited varieties of plants like Bradford pears and junipers.

When non-native plants "escape" from our landscape and take over natural areas they choke out the wide variety of native plants on which wildlife depends. Our desire for large lawn lots results in significant clearance of natural areas which fragments wildlife habitat. While less than 10% of all insects are harmful to plants, most pesticides are harmful or lethal to all insects. The industry maintains a dominant focus on horticultural planting strategies instead of advocating more complex ecological based plantings. We have become our own worst enemy in perpetuating traditional solutions as the basis of most designs.

A dramatic shift in conventional thinking is necessary to address sustainability in the core of the landscape and nursery industry. The industry needs to develop viable solutions to lawns and corporate landscapes in favor of diverse ecological natural communities which value biodiversity. We need to shift the basis of the green economy from low skilled lawn maintenance labor to more technically knowledgeable resource managers. Along with this paradigm shift comes increased market value and revenue opportunities. The need for biodiversity can be a catalyst in reforming traditional practices into a sustainable future.

Consumption of Natural Resources

The world only has a limited supply of natural resources and consumption rates are increasing. The United States is the world's largest consumer in absolute terms for many resources, eleven of the top twenty. Opportunities for using less are limitless when we look at our consumer economy. Principles for reducing consumption of natural resources can be applied to every aspect of business when you look at areas like packaging, recycling, specifying locally produced goods and use of low environmental impact materials.

Looking specifically at the landscape and nursery industry, specific opportunities emerge when we focus on business operations such as reducing fuel for landscape equipment, conserving water when irrigating plants, mitigating soil lost through erosion and eliminating peat moss or other harvested organic materials to amend soils. The green industry is indirectly responsible for 30% of water consumption in urban areas in the eastern United States for watering lawns, and in the West this figure is 60%. Guidelines for reduction or elimination of irrigation water are commonly available, but the environmental ethics need to be embraced by the entire industry. The green industry can be a powerful advocate in promoting sustainable solutions.

The world is shifting towards an environmental paradigm which fundamentally changes how we conduct every aspect of our lives. This green wave of change is upon us and it is our decision to sink or swim. We can allow the wave to overwhelm the industry or we can choose to participate as leaders riding the wave to a prosperous future of limitless opportunities. The future will be best defined for our industry internally by creative, innovative professions who have a passion for environmental change and civic commitment. By embracing the challenges to redefine our businesses practices at the most basis levels the industry will be guaranteed a meaningful front row seat in the new green economy. There is a lot of work to be done and a short amount of time available, so let’s get started in building a new green foundation for the future.

“Do not go where the path may lead, go instead where there is no path and leave a trail.”

Ralph Waldo Emerson