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Ecosystems and sustainable development
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- Scales of Ecosystems
- Sustainable development. Nature protection
Ecosystems and sustainable development Ecosystems and populations The term ecosystem (or ecological system) refers to communities of organisms and their environment. Ecosystems can vary greatly in size. Small ecosystems occur in tidal pools, in a back yard compost pile, or in the rumen of an individual cow. Larger ecosystems can include a lake or forest. Landscape-scale ecosystems comprise still-larger regions. Ultimately, all of Earth's life and its physical environment represents an ecosystem known as the biosphere. With so much variation in what constitutes an ecosystem, it is useful to define the barrier of the system that is being studied. Depending on the specific interests of an ecologist, an ecosystem might be delineated as the shoreline vegetation around a lake, or perhaps the entire water body, or maybe the lake plus all the land that drains into the lake (a watershed).Ecosystems take various forms of energy and simple inorganic materials, and create relatively focused combinations of these, occurring as the total amount of biological material (the biomass) of plants, animals, and microorganisms. Solar electromagnetic energy, captured by the chlorophyll of green plants, is a common energy source of many ecosystems. The most important of the simple inorganic materials are carbon dioxide, water, and ions or small molecules containing nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, and some other nutrients. Virtually all ecosystems (and life itself) rely on inputs of solar energy to drive the physiological processes by which biomass is synthesized from simple molecules. To carry out their various functions, ecosystems also need access to nutrients. Unlike energy, which can only flow through an ecosystem, nutrients can be utilized repeatedly. Through biogeochemical cycles, nutrients are recycled from dead biomass back into living organisms. One of the greatest challenges facing humans and their civilization is understanding the fundamentals of ecosystem organization— how they function and how they are structured. This knowledge is absolutely necessary if humans are to design systems that allow a sustainable utilization of the products and services of ecosystems. An example of a disastrous influence of humans on an ecosystem is the collapse of the cod fishery on the Grand Banks. This expanse of the Atlantic Ocean off the Eastern Coast of Maine and Atlantic Canada was once home to seemingly unlimited numbers of cod. However, over centuries destructive fishing practices and overfishing decimated the cod stock to the point where the species became nearly extinct. As of 2013, cod stocks have not recovered to sustainable levels. Populations A population comprises all the individuals of a given species in a specific area or region at a certain time. Its significance is more than that of a number of individuals because not all individuals are identical. Populations contain genetic variation within themselves and between other populations. Even fundamental genetic characteristics such as hair color or size may differ slightly from individual to individual. More importantly, not all members of the population are equal in their ability to survive and reproduce. Communities 583
Community refers to all the populations in a specific area or region at a certain time. Its structure involves many types of interactions among species. Some of these involve the acquisition and use of food, space, or other environmental resources. Others involve nutrient cycling through all members of the community and mutual regulation of population sizes. In all of these cases, the structured interactions of populations lead to situations in which individuals are thrown into life or death struggles. In general, ecologists believe that a community that has a high diversity is more complex and stable than a community that has a low diversity. This theory is founded on the observation that the food webs of communities of high diversity are more interconnected. Greater interconnectivity causes these systems to be more resilient to disturbance. If a species is removed, those species that relied on it for food have the option to switch to many other species that occupy a similar role in that ecosystem. In a low diversity ecosystem, possible substitutes for food may be non-existent or limited in abundance. Ecosystems Ecosystems are dynamic entities composed of the biological community and the a biotic environment. An ecosystem's a biotic and biotic composition and structure is determined by the state of a number of interrelated environmental factors. Changes in any of these factors (for example: nutrient availability, temperature, light intensity, grazing intensity, and species population density) will result in dynamic changes to the nature of these systems. For example, a fire in the temperate deciduous forest completely changes the structure of that system. There are no longer any large trees, most of the mosses, herbs, and shrubs that occupy the forest floor are gone, and the nutrients that were stored in the biomass are quickly released into the soil, atmosphere and hydrologic system. After a short time of recovery, the community that was once large mature trees now becomes a community of grasses, herbaceous species, and tree seedlings. What is an Ecosystem? An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, and atmosphere). In an ecosystem, each organism has its' own niche or role to play. Consider a small puddle at the back of your home. In it, you may find all sorts of living things, from microorganisms to insects and plants. These may depend on non-living things like water, sunlight, turbulence in the puddle, temperature, atmospheric pressure and even nutrients in the water for life. (Click here to see the five basic needs of living things) This is very complex, wonderful interaction of living things and their environment has been the foundations of energy flow and recycle of carbon and nitrogen. Anytime a ‘stranger’ (living thing(s) or external factor such as rise in temperature) is introduced to an ecosystem, it can be disastrous to that ecosystem. This is because the new organism (or factor) can distort the natural balance of the interaction and potentially harm or destroy the ecosystem. Click to read on ecosystem threats (opens in new page). 584
Usually, biotic members of an ecosystem, together with their biotic factors depend on each other. This means the absence of one member or one biotic factor can affect all parties of the ecosystem. Unfortunately, ecosystems have been disrupted, and even destroyed by natural disasters such as fires, floods, storms and volcanic eruptions. Human activities have also contributed to the disturbance of many ecosystems and biomes. Scales of Ecosystems Ecosystems come in indefinite sizes. It can exist in a small area such as underneath a rock, a decaying tree trunk, or a pond in your village, or it can exist in large forms such as an entire rain forest. Technically, the Earth can be called a huge ecosystem. The illustration above shows an example of a small (decaying tree trunk) ecosystem To make things simple, let us classify ecosystems into three main scales. Micro:
A small scale ecosystem such as a pond, puddle, tree trunk, under a rock etc. Mess:
A medium scale ecosystem such as a forest or a large lake. Biome: A very large ecosystem or collection of ecosystems with similar biotic and a biotic factors such as an entire rainforest with millions of animals and trees, with many different water bodies running through them. Sustainable development. Nature protection Sustainable development is a process for meeting human development goals while sustaining the ability of natural systems to continue to provide the natural resources and ecosystem services upon which the economy and society depends. While the modern concept of sustainable development is derived most strongly from the 1987 Brundtland Report, it is rooted in earlier ideas about sustainable forest management and twentieth century environmental concerns. As the concept developed, it has shifted to focus more on economic development, social development and environmental protection. Sustainable development is the organizing principle for sustaining finite resources necessary to provide for the needs of future generations of life on the planet. It is a process that envisions a desirable future state for human societies in which living conditions and resource-use continue to meet human needs without undermining the "integrity, stability and beauty" of natural biotic systems. 585
The Blue Marble, photographed from Apollo 17 in 1972, quickly became an icon of environmental conservation. Sustainability can be defined as the practice of maintaining processes of productivity indefinitely—natural or human made—by replacing resources used with resources of equal or greater value without degrading or endangering natural biotic systems.[2] Sustainable development ties together concern for the carrying capacity of natural systems with the social, political, and economic challenges faced by humanity. Sustainability science is the study of the concepts of sustainable development and environmental science. There is an additional focus on the present generations' responsibility to regenerate, maintain and improve planetary resources for use by future generations.[3] The Sustainable Development Goals (SDGs) On September 2015, the United Nations General Assembly formally adopted the "universal, integrated and transformative" 2030 Agenda for Sustainable Development, a set of 17 Sustainable Development Goals (SDGs). 
These icons represent the 17 headline SDGs. There are 169 targets under the goals.
The goals are to be implemented and achieved in every country from the year 2016 to 2030. Dimensions 
Scheme of sustainable development: at the confluence of three constituent parts. (2006) 586 Sustainable development, or sustainability, has been described in terms of three spheres, dimensions, domains or pillars, i.e. the environment, the economy and society. The three-sphere framework was initially proposed by the economist René Passet in 1979.] It has also been worded as "economic, environmental and social" or "ecology, economy and equity. This has been expanded by some authors to include a fourth pillar of culture, institutions or governance. жүктеу/скачать 18,66 Mb. Достарыңызбен бөлісу:
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