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What Are Ecosystem Services?
Ecosystem services are defined generally as the benefits that humans receive from natural ecosystems. They provide, in one way or another, just about all of the resources we as people have and allow for our current quality of life (whether that be good or bad). This concept of ecosystem services, of quantifying dynamic natural ability, becomes increasingly important as the world population grows. As the human population increases, our presence and thus our influence spreads and subsequently natural ecosystems begin to diminish. This reduces the availability of ecosystem services while at the same time increases the demand for these same resources, putting us in a seemingly cyclical pattern of ever-expanding problems.
A large part of applying the concept of ecosystem services to everyday life nowadays is assigning a monetary value to these services and being able to harvest and market them efficiently and ideally, sustainably. To be able to do this you need not only a solid understanding of the ecology of the services, but of the related economics of the system as well. To start out slow, in order to easily view the types of services available and what they provide us with, they are divided into four main categories based on what is provided and how it is provided.
The first main group is provisioning services, also known as the products obtained from ecosystems. This encompasses a huge range of things including, but most certainly not limited to, production of food, water, fibers, medicines, construction materials, energy (such as wind power, water power, and biofuels), and even genetic resources used in processes such as genetic modification of crops and food animals and identifying diseases.
The second main group is regulating services which are the benefits obtained from the regulation of ecosystem services. Examples of this are the regulation of climate (such as cloud creation or regulating carbon, nitrogen, and sulfur discharge), regulation of pests, disease, and waste decomposition (waste water treatment, composting), purification of water and air, and pollination via bee husbandry.
The third main group is the cultural services. These are defined as the non-material benefits humans obtain from ecosystems through spiritual enrichment, cognitive development, reflection, recreation, and aesthetic experience. Examples of these are numerous and include both the recreational and spiritual use of naturally occurring psychoactive substances such as ayuhuasca, Amanita muscaria (fly agaric), tobacco, marijuana, psylocibin-containing fungi, kava kava root, and nightshades. Cultural services also include ecotourism, knowledge systems created through research and observation, and the aesthetic properties of products such as shells, antlers, trees, gardens, and the like.
The fourth and last main group of ecosystem services is the supporting services. These are the big picture services, those that are required for the production of all other ecosystem services. Examples of this include biomass production, sedimentation (both the formation and retention of sediment), nutrient dispersion and cycling (carbon cycle, nitrogen cycle, etc.), water cycling, seed dispersion, natural pollination, and habitat creation.
As mentioned before, understanding ecosystem services requires a solid understanding of ecology, that being the interactions between organisms and their environment. Ecosystem services are studied from an ecologist’s point of view by first identifying the organism (or group of organisms) that acts as the service provider, and then characterizing those organisms’ roles and relationships as a part of the ecosystem. This means not only looking at the service provider, but all other components of the ecosystem it is a part of, both biotic and abiotic. Aspects such as community structure, population size, organism dispersal, and time-frame of the service components (among many other things) are all taken into account in order to achieve a thorough understanding of the inputs and outputs of the service.
To better understand the magnitude of the influences on a system, here is an easy-to-understand example. If you wanted to, for instance, determine an acceptable amount of annual CO₂ discharge from an industrial facility, you would need to know at what rate this carbon becomes either fixed or safely dissipated. To determine this rate you have to look at each component of the system individually and then how these relate to each other. So let us first look at terrestrial plant carbon fixation. The rate at which these plants can remove carbon from the atmosphere is dependent on the size of the plant, the metabolic rate, the dispersal pattern (how clumped or spread out they are), the types of chlorophyll present, the concentration of chlorophyll, and a number of other factors. These factors are in turn affected by variables such as location of the plants, cloud cover, wind speed, wind duration, fetch, and others because they affect how much light the plant receives, which affects growth and metabolism. Additionally, factors such as soil type, terrain slope, and rainfall will determine how much water the plants receive, which in turn affects metabolism and growth as well.
There can also be multiple paths for the ecosystem service to be provided, for example, carbon is not only fixed by photosynthetic organisms, but also in part by certain aquatic animals. Organisms that create calcium carbonate (CaCO₃) structures such as corals, bivalves, and gastropods gather and concentrate aqueous carbon-containing molecules, semi-permanently removing them from the water column and the atmosphere. Knowing how much carbon they can gather and fix requires taking a look at distribution patterns, population size, metabolic rates, body size, and other related variables of the given species. Aquatic fixation is then regulated by a number of abiotic factors just as terrestrial fixation is such as wave action, wind speed, wind duration, concentration of CO₂ in both the air and water, water temperature, and geography among many others.
Carbon is also imputed into the cycle not only through industrial emissions, but through the processes of respiration, decay, and defecation as well. Due to this fact, you cannot calculate and acceptable level of discharge without also taking into account the factors other than your own facility that contribute to the carbon content of the atmosphere. Similarly, there may be other similar operations happening nearby that would also contribute, so properly understanding ecosystem services is not merely studying the species or component that provides the services, but studying the entire ecosystem that interacts, supports, and is supported by, that species or component. You must look at your facility not as its own entity, but as an interactive part of the ecosystem itself if you want your operation to be “environmentally-friendly” or “sustainable”.
If you are not looking for safe solutions to our more-often-than-not degrading environment, you are likely part of the problem. This is because a large portion of the threats to the availability of ecosystem services stem from the ever-increasing size of the world population. Not only has the population been on the rise since just about forever, it is projected by the U.S. Census Bureau to continue to grow until to at least nine billion people. In regards to our current resource usage, if everyone were to use like the U.S. uses, we would not have enough resources in the world to sustain all of that life. In addition to simple scarcity of resources, the huge population also negatively affects ecosystems through activities like poor waste management (agricultural runoff, human waste, industrial waste), light pollution, sound pollution, habitat destruction (food monoculture, over-harvesting, construction, deforestation), and habitat alteration (introduced species, climate alteration, herbicide and pesticide use). Similarly, poor or absent regulation (maximum sustainable yield calculated incorrectly, economically-based rather than ecologically-based decisions), and poor communication between ecologists and economists pose a threat to these services as well. Though in the defense of some of these people, it is likely hard to translate a language describing dynamic system processes into a rigid numerical language. And of course, there are natural threats to ecosystem services as well such as climate change, natural disasters, and storms. All of these things could reduce biodiversity and subsequently destabilize the ecosystem equilibrium and reduce the output and efficiency of many ecosystem services.
In order for some form of balance to occur, there must be a reasonable system for assessing ecosystem services economically. While what is reasonable is up for debate, what people do in general is to start by determining the average ecological yields of the service, which in the case of food production would be how much food, or in other cases may be how many plants can be pollinated, or how much nitrogen algae removes from the water column. This number is then converted to economic yield by giving it a monetary value based on market demand. Subtracted from this new number are the estimated losses. For example in the carbon cycle, losses to acceptable discharge occur from natural metabolic processes in addition to other facilities. If you were looking at a food provisioning service, losses might occur from pests, disease, poor growing conditions, and anything else that reduces yields. Value is also contributed to the service through job creation, job creation potential, and future value potential of the product.
In an economist’s language, value is applied to an ecosystem service in six basic ways. The first is avoided cost, which allows society to avoid costs that would be present without the service. Examples of this include wastewater treatment by wetlands or air purification through photosynthesis that would prevent future healthcare costs.
The second way to apply value is replacement cost, which is how much it would take to replace a service with a man-made system. A well-known example of this is the case of the Catskill watershed. In this situation, New York was having water quality issues that needed to be addressed. Scientists discovered that it would cost less money to restore the watershed ecosystem than to create a water purification plant.
Another way to apply value is the travel cost. This, simply enough, means that if a service requires travel, that can be incorporated into the value. For example, ecotourism is worth at a minimum what people are willing to pay to get there and back, in addition to other money spent during the journey.
Value can also be assessed by looking at factor income: when services enhance income. This exists in situations such as when you improve water quality, you enhance fish growth and health, which in turn increases fishermen’s yields and thus their income.
There is also hedonic pricing, which means that demand is reflected in the prices that people will pay for associated goods. This is apparent in the fact that coastal houses are more expensive than inland houses and the fact that ecotourism brings in more money in areas with higher perceived aesthetic value. People want the warm weather, the water, the sand, the local biodiversity, and they will pay more to have it.
Lastly, value is often assessed through contingent valuation. This refers to the value of a service in comparison to its alternatives. For example, visitors will pay more for increased access to a national park, or for more highly-purified water.
After all of this has been considered, and we understand what we are looking at, we are still left with a host of ethical questions concerning ecosystem services. One of the biggest questions out there is: can we assign an appropriate monetary value to a dynamic system service? Of course we can set up standards and analyze the service based on these standards, but who determines what to look for and how much value that aspect has? How do we know when that value becomes outdated? Or who can contest the legitimacy of those values? Do we want ecologists, economists, or both working on this? Maybe we want people who are neither to be a part of the decision-making process as well, because they have a say in what goes on in their environment too. Who is to say their thoughts are not equally as important? Say we do come to something somewhat resembling an agreement, does putting this value on nature make us more or less likely to abuse the ecosystems? Will we feel that we deserve at least what has been determined as an acceptable harvest? Does that change if the population of the service provider declines? Or perhaps having these values will allow us to more easily and effectively monitor our resources and use them more responsibly.
Other ethical questions are raised after valuation as well such as: do landowners have the right to alter the local ecosystem on their land as they please, even if the results negatively affect the lives of others? For example, if a company wants to clear away a section of a forest to increase their production area but that leaves a nearby village lower on the slope open to flood damage, whose rights hold priority? Are legal agreements more important than innocent lives? Or, if that same area is a breeding ground for a keystone species that the natives depend on for food, can it just be cleared away for personal gain despite the natives?
No matter what the answers are, the decisions are up to the people. Whether these people are the numerous pawns in a large corporation, the few that still live off the land, the wealthy, the poor, the needy, or the greedy, they all have to put their interests on the same table before we as people can come to any sort of agreement. More than likely, there will never be an answer that satisfies everyone, and until then, all we can do is learn, listen, react, and act. Hopefully, we won’t do too much damage to our home in the process.