Introduction
With the world economies improving and expanding at an alarming rate, individual government are more than ever before challenged by the task of dwindling natural resources, and this has led to the questioning of exactly how sustainable such resources are. In fact, the issue of environmental sustainability transcends natural, social and ethical dimensions. In this regard, most of these natural resources, chief of which is crude oil, are have witnessed a higher consumption rate that exceeds their rate of formation, with a global decline in its production pegged at the year 2020 (Murray 2005).
Main
On to matters of forests and land, most of the hitherto forest-covered lands are today being cleared away, as a result of human encroachment for purposes of cultivation and wood. Though the destruction of the environment may be localised, their impact effects are felt globally. This then calls for a global input in the protection of our natural resources (Sohngen & Sandra 2004). Furthermore, even the sustenance of individual basic needs for anybody in any part of the planet, ought to be the concern of everyone. The utilisation of the world resources ought to be done so with the plight of the later generations in mind. For this reason, there should be equity in the inter-generational access of resources. Furthermore, the control of pollution is one way of ensuring that the later generations too, are able to enjoy the resources (Jayanetti & Follett 2004).
Striking a balance between economic development and resources consumption may be the needed dose to ensuring the sustenance of natural resources. Dubbed the green development, the move is a culmination of efforts by environmentally-friendly organisations such as UNEP and World Wide Fund for Nature (WWF), with a view to maintaining ecological and life support systems, as well as in the preservation of the genetic diversity, while ensuring a sustainable utilization of both the ecosystems and that of species (Sohngen & Sandra 2004).
This is how then, that the concept of bio-based materials came into being. Its defining criteria states that the said materials should be sourced from sustainably grown and harvested cropland or forests. In addition, they ought to be manufactured with no hazardous impacts or inputs, and should be safe to the environment during use, and be recyclable. These renewable materials are finding use as bioproducts, and in the field of bioenergy. Bio-based materials are poised to offer an alternative to petroleum-based fuels and polymers which, while having benefited mankind all these years, are now posing a danger to the environment by virtue of their toxic emission, resulting into global warming (Murray 2005).
Additionally, these materials are a source of litter, leading to landfill problems, owing to non-recyclable polymers. Moreover, petro-based and synthetic products are finite in nature. Governments the world over, and notably in China, have so far enacted policies meant to rid of the cities and towns from plastic pollution. In contrast, bioplastics are not only more sustainable, they rely less on fossil fuels for carbon source, thus emitting less greenhouse gas. These have now been incorporated into the renewable energy family, which also includes bio-based fuel and engineering wood. Currently, bio-based materials seem the most practical solution to the energy peaks situations being witnessed globally, as the world gears up to face the emerging crisis in the sustainable energy (Sohngen & Sandra 2004).
The need for sustainable energy has seen focus being shifted onto indigenous materials that are often shunned, or whose purposes have hitherto not been fully utilised. Chief among these sustainable resources is timber. However, forests are at an increased risk, owing to the rise in demand for wood, timber and fodder. This has not only seen the encroachment of forests land, but climate change has been experienced as well. According to WWF (2000), about 0.42 hectares of forest are lost every second (Jayanetti & Follett 2004). This should be a concern to everyone.
Ultimately, the discovery of a renewable and sustainable material to the environment while being responsible to human needs and the ecology should be the primary focus of all. In light of this, researchers have now turned to the study of bamboo, hemp, and strawbale as replacements to wood. Of late, bamboo has found wide application as a roof, panelling, floor, and furniture material, thereby replacing hardwood products (Murray 2005). Research now shows that bamboo is not only excellent as a building replacement material, but its strength is three times of wood, similar to steel panels. The potential for its use is enormous, as already, more than one billion people live in bamboo houses (Follett & Jayanetti 2004 p.102).
Its wide distribution, short term growth cycle, multi-functional and higher ecologic and economic value, makes it a perfect replacement for wood. Furthermore, its growth cycle is shorter, with a possible harvesting every three to five years. In addition, bamboo beams exhibits excellent characteristics such as high strength, light weight, easy to construct, and good resistance to fire and decay. On the other hand, hemp, a cannabis species is the world strongest fibre. This has seen it being used traditionally in the textile industry. With a short and less demanding growth cycle, Hemp attains maturity at four months, while most trees take approximately 20 years to be mature (Murray 2005).
As a bio-based material, all its parts are useful, and are also an excellent source of fuel. According to Herer (2000 p. 97), hemp is non-toxic and had been used to make high-grade diesel fuel, oil, aircraft and precision oil, as well as vegetable oil. Herer (2000, p.98) opines that hemp is the best sustainable source of plant pulp for biomass fuel to make charcoal, gas, methanol, gasoline and electricity in the most natural way. Another sustainable material is the strawbale, which is a by-product of wheat. Of late, the materials have received extensive research, with a major discovery that combining strawbales with plaster supports high level thermal constructions.
A well built straw bale home is said to save as much as 75 percent in terms of heating and cooling costs (Jayanetti & Follett 2004). Gibson (2006) asserted that Straw bale homes have approximately three times the fire resistance of normal homes. However, the burning of strawbale emits toxic fumes and carbon dioxide, thus endangering the lives of people. Still, the emission is no where near the toxic level of petro-based products. Its use will thus help reduce environmental pollution, while saving on wood consumption. Although the success of bio-based materials is not in dispute, the issue of their usage in dogged with an ethical dilemma.
Critics have not hesitated to connect their usage with the wastage of natural resources, leading to a food crisis, and especially the wastage of water resources in their cultivation (Murray 2005). With regard to food, lobby groups have been up in arms, arguing that the cultivation of bio-based materials will not only encroach on the land meant for the cultivation of crops, but that such food crops will also be expensive, thus resulting in looming hunger (Jayanetti & Follett 2004). In as much as bio-fuels are poised to replace fossil fuels as an energy source, claims have been put forward by scholars that the practise of say, acquiring ethanol from corn expends give more energy than it gives up (Herer 2000).
There is a need therefore, to address such ethical issues; if at all the fight for environmental sustainability is to be achieved. Another source of bio-based materials is algae. Some species of algae are credited with the photosynthetic ability to convert sunshine into chemical energy. This chemical energy so converted, is in the form of oils, same as the common vegetable oil. These oils can then be processed to produce biodiesel (Murray 2005). The production of algae uses 99 percent less water than conventional agriculture, with no soil required for growth. Furthermore, algae are extremely efficient in use of light and absorption of nutrients. So much so that their growth and productivity is 30 to 100 times higher than crops like soybeans (Sohngen & Sandra 2004).
Owing to their high photosynthetic performance, algae utilises high concentrations of carbon dioxide, and can thus be used to clean up the air, with a dramatic reduction in global warming (Murray 2005). As a biofuel source, algae is cheap to produce, with the remaining carbohydrates following oil extraction finding use as animal feed, ethanol, and a potential carbon sequester (Herer 2000). Lately, there is an emerging trend in the production of cellulose ethanol, sourced from wood chips, agriculture waste, and switch grass. The objective here is to develop a cost effective production of clean bioethanol from lignocellulosic biomass (LCB), thus enabling its use as a transport biofuel. Still at its infancy stage, the use of this technology is being verified using a unique and fully integrated pilot plant (Herer 2000). The aim is to provide reliable data for global socio-economic and environmental assessments and for the design of a future demonstration unit.
Without doubt, the greatest crisis that is proving to be a global challenge is that of sustaining economic growth. To achieve this, energy is a key requirement. Previously, we have overly relied on non-renewable resources such as crude oil. With the global production of oil poised peak at 2020, the resources will thereafter plummet with regard to output (Sohngen & Sandra 2004). However, this is not the only reason why we should be worried. Pollution and the emission of gas from these fossil fuels have taken their toll, leading to global warming.
Conclusion
In essence, the rate at which energy is being consumed could as well endanger the existence of later generations. For this reason, focus should be on sustainable energy sources. This focused has in essence paved way for bio-based materials such as bamboo, hemp, algae, strawbale and production of cellulose ethanol, to name but a few. These materials are not only renewable, but some like the algae have the potential to reduce pollution, and are cheaper, and affordable (Murray 2005). Their cultivation has however been mired by controversy, with the issue of ethics coming to light. If a lasting solution to the sustenance of natural resources is to be attained, then there is a need to involve all the parties involved (Jayanetti & Follett 2004). This way, policies that address the needs of everyone shall be implemented, thereby settling the issue of energy consumption and sustenance once and for all.
References
Gibson, G (2006). ‘Hemp in the British Isles’. Journal of Industrial Hemp. 11 (2) p.127.
Herer, J (2000). The emperor wears no clothes. America: Quick American Archives.
Jayanetti Lionel, J and Follett, P (2004). ‘Earthquake-proof house shakes bamboo world: Proceedings of the Institution of Civil Engineers’ Civil Engineering Values. 157(3) p.102.
Murray, H (2005). Practical Straw Bale Building. Australia: Landlinks Press.
Sohngen, B. and Sandra, B (2004) ‘Measuring leakage from carbon projects in open economies: a stop timber harvesting project in Bolivia as a case study’. Canadian Journal of Forest Research. 34 (4) pp 829-840.