Renewable resource

A renewable resource is a natural resource with the ability of being replaced through biological or other natural processes and replenished with the passage of time. Renewable resources are part of our natural environment and form our eco-system.

An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving (abiotic), physical components of the environment with which the organisms interact, such as air, soil, water and sunlight.

Classification: Ecosystems have become particularly important politically, since the Convention on Biological Diversity (CBD) - ratified by 192 countries - defines "the protection of ecosystems, natural habitats and the maintenance of viable populations of species in natural surroundings" as a commitment of ratifying countries. This has created the political necessity to spatially identify ecosystems and somehow distinguish among them. The CBD defines an "ecosystem" as a "dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit".

With the need of protecting ecosystems, the political need arose to describe and identify them efficiently. Vreugdenhil et al. argued that this could be achieved most effectively by using a physiognomic-ecological classification system, as ecosystems are easily recognizable in the field as well as on satellite images. They argued that the structure and seasonality of the associated vegetation, or flora, complemented with ecological data (such as elevation, humidity, and drainage), are each determining modifiers that separate partially distinct sets of species. This is true not only for plant species, but also for species of animals, fungi and bacteria. The degree of ecosystem distinction is subject to the physiognomic modifiers that can be identified on an image and/or in the field. Where necessary, specific fauna elements can be added, such as seasonal concentrations of animals and the distribution of coral reefs.

Several physiognomic-ecological classification systems are available:

Physiognomic-Ecological Classification of Plant Formations of the Earth: a system based on the 1974 work of Mueller-Dombois and Heinz Ellenberg, and developed by UNESCO. This classification "describes the above-ground or underwater vegetation structures and cover as observed in the field, described as plant life forms. This classification is fundamentally a species-independent physiognomic, hierarchical vegetation classification system which also takes into account ecological factors such as climate, elevation, human influences such as grazing, hydric regimes and survival strategies such as seasonality. The system was expanded with a basic classification for open water formations".

In 1962, within a report to the committee on natural resources which was forwarded to the President of the United States, Paul Weiss defined Renewable Resources as: "The total range of living organisms providing man with food, fibers, drugs, etc...".Renewable resources are endangered by industrial developments and growth. They must be carefully managed to avoid exceeding the natural world's capacity to replenish them. A life cycle assessment provides a systematic means of evaluating renewability. This is a matter of sustainability in the natural environment. Solar radiation, tides, winds, geothermal, biomass and other natural elements are renewable resources of energy now called renewable energies. Gasoline, coal, natural gas, diesel and other commodities derived from fossil fuels, as well as minerals like copper and others, are non-renewable resources without a sustainable yield.

Renewable energy: Solar energy is the energy derived directly from the Sun, and is the most abundant source of energy on Earth. The fastest growing type of alternative energy, increasing at 50 percent a year, is the photovoltaic cell, which converts sunlight directly into electricity. The Sun yearly delivers more than 10,000 times the energy that humans currently use. Wind power is derived from uneven heating of the Earth's surface from the Sun and the warm core. Most modern wind power is generated in the form of electricity by converting the rotation of turbine blades into electrical currents by means of an electrical generator. In windmills (a much older technology) wind energy is used to turn mechanical machinery to do physical work, like crushing grain or pumping water.

Hydropower is energy derived from the movement of water in rivers and oceans (or other energy differentials), and can likewise be used to generate electricity using turbines, or can be used mechanically to do useful work. It is a very common resource. Hydropower appeared centuries ago with the first use of a power turbine to produce electricity. Geothermal power comes the Greek words, "geo" meaning Earth and "thermal" meaning heat. Geothermal directly harnesses the natural flow of heat from the ground. The available energy from natural decay of radioactive elements in the Earth's crust and mantle is approximately equal to that of incoming solar energy. For information on solar energy for home please check home solar energy and for information about installing solar panels please check solar panel installation. The first geothermal power station was built at Landrello, Italy. Other countries that have geothermal power stations are Japan, Iceland, the Philippines and the United States. In Iceland, geothermal energy is used for electricity and heat.

Alcohol derived from corn, sugar cane, switchgrass, etc. is also a renewable source of energy. Similarly, oils from plants and seeds can be used as a substitute for non-renewable diesel. Methane is also considered as a renewable source of energy. Renewable resources such as solar energy, wind, hydropower, and geothermal energy have many benefits. These resources can reduce carbon dioxide emission, water consumption, and waste. Clean air is vital on this planet because it can reduce human health problems such as asthma (children are at a higher risk) and lung disease. Renewable resources can also lead to environment sustainability because these resources will not be depleted and stimulate the economy by creating more job opportunities.

Renewable materials

Agricultural products: Techniques in agriculture which allow for minimal or controlled environmental damage qualify as sustainable agriculture, and it is also known as sustainable farming. Products (foods, chemicals, biofuels, etc.) from this type of agriculture may be considered "sustainable" when processing, logistics, etc. also have sustainable characteristics.

Water: Water can be considered a renewable material (also non-renewable) when carefully controlled usage, treatment, and release are followed. If not, it would become a non-renewable resource at that location. For example, groundwater is usually removed from an aquifer at a rate much greater than its very slow natural recharge, and so groundwater is considered non-renewable. Removal of water from the pore spaces may cause permanent compaction (subsidence) that cannot be renewed.