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Розділ 1 Економіка природокористування і еколого-економічні проблеми
МЕТОДОЛОГІЧНІ ПРОБЛЕМИ СУЧАСНОЇ ЕКОНОМІКИ
Економіка природокористування і
The Economic Value of Biodiversity Loss:
Understanding the Role of Ecosystem Services
The article is devoted to the problem of biodiversity value loss of ecosystems. Ecosystems – our natural capital – are the basis of life its self. Without them there would be no place for people on earth.
The value of particular species in particular ecosystems derives from the value of the goods and services those species support, it is conventional to distinguish between two different types of value: use and non-use (or passive use) values.
In the result of investigation the necessity to understand what we lose when we lose biodiversity and ecosystem services was commented and proved, the relationship between biodiversity, ecosystem services, and human well-being was presented and learned for using knowledge to better target our conservation efforts.
What is the economic value of ecosystem services? In a now famous paper published in 1997, Costanza et al (1997) estimated that ecosystem services were worth some US$33 trillion a year. This is a large number, and it served its purpose in attracting the attention of scientists and policy-makers alike, but did it help us to understand the value of ecosystems? Probably not. For one thing ecosystems – our natural capital – are not quite the same as bricks and mortar. They are the basis of life itself. Without them there would be no place for people on earth, so their loss could not be compensated. As one economist put it after the appearance of the Costanza et al paper, ‘US$33 trillion is a serious underestimate of infinity’. Yet many economists have since spent considerable time trying to understand the economic value of environmental assets has been changing and why.
Many others have also spent considerable time trying to persuade us that biodiversity and ecosystems are beyond price, even at the margin, and that the values that matter to conservation are ethical or moral values (Unger, 2004). The Convention on Biological Diversity refers to the ‘intrinsic’ value of biodiversity, and many of those advising policy makers rest their arguments heavily on the fact that intrinsic and economic values are different. One well-known (and thoughtful) economist put it this way:
‘If our concern is to conserve these [ecosystem] services, then valuation is largely irrelevant. Let me emphasise this: Valuation is neither necessary nor sufficient for conservation. We conserve much that we do not value, and we do not conserve much that we value.’ (Heal, 2000).
The way I interpret this comment is that if we look at the current pattern of conservation around the world it does not correspond very well with what we understand about the economic value of ecosystem services or biodiversity. Should it do so? I suggest that the answer to that is unambiguously ‘yes’. We need both to understand what we lose when we lose biodiversity and ecosystem services, and we need to use this knowledge to target our conservation efforts.
To see why, let me first revisit the basis of economic value and it’s connection with ethics and morality. Let me begin with price. The price a good or service can command is its value to the ‘marginal buyer’. For any given price there are likely to be people who are willing to pay more than that price, but whose behaviour does not influence the price. It is the behaviour of those who would choose more of the good if the price were a little lower, or less if the price were a little higher that matters. Under the utilitarian philosophy this makes the price of a good or service a measure of what society would gain or lose if a little more or less were available. In well-functioning markets it is a measure of the social opportunity cost of the good or service.
The price of ecosystem services, like the price of other services – what the marginal buyer is willing to pay – reflects its scarcity. In the early 19th century, David Ricardo put it this way:
‘The labour of Nature is paid, not because she does much, but because she does little. In proportion as she becomes niggardly in her gifts, she exacts a greater price for her work. Where she is munificently beneficent, she always works gratis.’
An important caveat to this is that since the current price of a good or service is a marginal measure, it does not say what society would gain or lose if a lot more or less were available. It is not therefore a measure of how important the good or service in aggregate may be to the very survival of humans or other species. The diamonds and water paradox that puzzled economists for more than a century – that diamonds are so unimportant to us yet so costly, while water is so important and yet costless – reflects the role of scarcity.
Now the economic value of an asset is the discounted flow of services it can provide in the future at expected prices. The mention of discounting here opens up a huge debate about the ethics of counting the well-being of future generations less than the well-being of the current generation, but I want to let that pass. The point is that if we understand the services we get from ecosystems, and if we can estimate the price or marginal value of those services at some agreed discount rate or sequence of rates, then we can, in principle, value ecosystems from the flow of services they provide.
Of course if there is no market for a good or service it will not have a market price. And if markets are incomplete, there may be a market price, but that price may fail to reflect the social opportunity cost or the true scarcity of the resource. In these circumstances people may be induced demand too much or too little of the good or service. Indeed, the underlying cause of biodiversity loss in many parts of the world is the fact that the markets for food and fibres which drive resource allocation in agriculture, forestry and fisheries do not generally signal the costs to society of private land conversion and agricultural specialisation.
Biological resources in exploited tropical forests, for example, have historically been valued by the market for the timber and other products that they yield, and for forest-based activities such as hunting, fishing, recreation and tourism. They have not been valued for their role in the provision of either global public goods (such as carbon sequestration) or local public goods (such as watershed protection, habitat provision, or nutrient recycling).
The value of particular species in particular ecosystems derives from the value of the goods and services those species support. It is conventional to distinguish between two different types of value: use and non-use (or passive use) values. There are variants of these terms, but they mean much the same thing. Use values refer to the value that biological resources have to people either directly or indirectly, and either through the consumption of those resources or the services they provide. The most familiar products of nature are also those for which markets are best developed. They include foods, fibres, fuels, biochemicals, genetic material, medicinal and other pharmaceutical products. They also include the aesthetic, amenity, spiritual, religious or totemic value of species, and what are termed quasi-option and scientific values, both of which refer to the information value of the resources concerned (Heywood, 1995; Pearce and Moran, 1994; Unger, 2004).
Indirect use values include the value of resources that do not enter directly into consumption but may be inputs into the production of other goods or services or life support services. Non-use values are generally those that involve consumption or use by third parties. That is, they include the value to people of the consumption of the resource by other people now or in the future, or by other species. The categories ‘intrinsic’ and ‘existence’ value usually refer to this.
The value of the mix of species biodiversity is derived in essentially the same way. Biodiversity underpins the production of goods through its role in supporting a set of ecosystem services. Ecosystem services include the regulation of atmospheric chemical composition; the regulation of global temperature, precipitation, and other biologically mediated climatic processes; the regulation of hydrological flows; the storage and retention of water; soil retention and soil formation; the cycling, processing, and acquisition of nutrients; seed dispersal; the trophic-dynamic regulation of populations and the provision of habitat (Daily, 1997).
The MA reflects the relationship between biodiversity, ecosystem services, and human well-being in the following figure. This draws attention to both the direct and indirect value of biodiversity, where the indirect value works through ecosystem processes, and distinguishes the different kinds of ecosystem service thought to be valuable: provisioning, cultural, supporting, regulating.
Source: Millennium Assessment (2004).
The link between anthropocentric and non-anthropocentric or intrinsic values is less easy to show. The recognition that intrinsic value matters is essentially an ethical position. It holds that we should have regard to the fact that ecosystems and the services they provide are not just valuable to humans but to other species as well. But to the extent that we take actions that involve choices and trade-offs using intrinsic value as the justification for those actions, we are assigning values, and hence are dealing with just another anthropocentric value. What can be said, though, is that the value of biodiversity and ecosystem services to other species rests on the same ecosystem processes and ecosystem functioning.
In economic terms, biodiversity is equivalent to a portfolio of assets, and community conservation effort is equivalent to investment in that portfolio (Swanson, 1992; Perrings, 1995). Technically, the level of conservation effort (investment in biodiversity) should depend on both the mean yield of the portfolio, and the covariance in yields. If different species vary in their sensitivity to environmental change, for example, then reducing the variety of species included in the portfolio increases the risk born by society. Lower diversity increases average yields (at least in the short run) but also increases risk. Conversely, greater diversity reduces overall risk, but at the potential expense of lower mean yields. Social attitudes towards risk will determine how much it is concerned about the effect of diversity on the variance of yields.
One long-recognised effect of genetic simplification in agriculture has been a reduction in system resilience (Conway, 1993). The costs of this include the cost of the herbicides, pesticides, fertilisers, irrigation and other inputs needed to maintain output in the simplified system. They include the cost of relief where output fails, relocation where soils or water resources have been irreversibly damaged, rehabilitation where damage is reversible and insurance against crop damage by pest or disease.
So what is the evidence for changes in the value of ecosystem services? I will use the not-quite-finalised Millennium Ecosystem Assessment to summarise the state of our knowledge. The MA identifies four different types of ecosystem service: provisioning services are responsible for the production of foods, fibres, fuels and other products; regulation services include, e.g., pollination, seed dispersal, climate regulation and the like; supporting services include ecosystem processes such as nutrient recycling, soil formation and water cycling; and cultural services include aesthetic, spiritual, cultural, religious and information services (see Table 1).
Table 1 – Ecosystem services
Source: Heywood (1995), Millennium Assessment (2004).
Only four of the ecosystem services examined by the MA have been enhanced in the last few decades: crops, livestock, aquaculture, and (in recent decades) carbon sequestration. Most other services have been degraded. The list of such degraded services includes capture fisheries, timber production, water supply, waste treatment and detoxification, water purification, natural hazard protection, regulation of air quality, regulation of regional and local climate, regulation of erosion, and many cultural services (spiritual, aesthetic, recreational and other benefits from ecosystems).
The MA also notes that the impact of the loss of biodiversity and ecosystem services depends on how rich or poor people are. In particular, poor people in rural areas in the South are more heavily dependent on biodiversity and ecosystem services than city-dwellers in the North. They are also more vulnerable to the degradation of those services. For example, the decline in capture fisheries especially affects the poor, since it provides a cheap source of protein. Similarly, agricultural intensification has enhanced production of major crops but has denied many access to food plants – especially landraces and their wild relatives – which have historically contributed to household nutrition.
The MA points out that many economic studies of land conversion in particular ecosystems (mangrove forests, coral reefs, and natural forests) show that if the full social effects are taken into account, the costs of conversion exceed the benefits.
Conversion nevertheless takes place because the social costs of the activity are ignored by those responsible. This may be because those costs lie outside the market. It may also be because land conversion is subsidized by government.
We can now ask what these changes imply for the value of the underlying ecosystems, recalling that the value of an asset is the discounted flow of services it yields.
The first point to make is that ecosystems can be thought of as a set of assets in the same way that we think about other assets. That is, the stock of assets available to us includes not only produced capital, and human capital but also natural or environmental capital. Most existing measures of capital neglect the latter. The most inclusive of all SNA measures, Net National Product (NNP), still excludes depreciation of both human and natural capital along with transboundary environmental flows. One attempt to capture at least the first of these was the genuine savings index (GSI) due to Hamilton and Clemens (1999) and Hamilton (2000), now referred to as Adjusted Net Savings. Dasgupta (2001) has developed the same idea, calling it genuine investment. It is a measure of the change in a country’s wealth.
Estimates of adjusted net savings are generally lower than other savings measures, reflecting the depreciation or degradation of many environmental assets. This is not always the case. Afforestation or soil erosion programmes, for example, may enhance the value of environmental assets, and in the following examples adjusted net savings exceed net savings in some countries and for some time periods.
What is more worrying are the cases where taking the change in natural assets into account turns positive net savings into negative adjusted net savings, implying that the countries concerned are eating into their natural capital.
When the effect of population growth is taken into account, the position is even worse. Dasgupta shows that inclusive wealth has declined in many countries in the last three decades (Table 2).
If ‘Nature’ has become scarcer we would expect that it would command a greater ‘price’. We certainly know that at least some people are willing to pay more for ecosystem services, and much work is being done to show that loss of biodiversity makes the remaining diversity more valuable to us – at the margin. Going back to the diamonds and water paradox, in some parts of the world water is becoming just a little more like diamonds. It is a genuinely scarce resource, and its price is rising. Nevertheless, in some parts of the world the value of natural capital, the aggregate stock of environmental assets, has declined. Why?
One reason for this is that willingness to pay depends on ability to pay, and hence on the distribution of income, and this is becoming more, not less inequitable. A look at the distribution of global assets in 1994 calculated by the World Bank shows the dramatic difference in asset holdings by the rich and poor (Figure 3). It also shows that the composition of wealth varied a great deal.
Human capital is more important than other types of capital in the rich countries, as expected. But what is more interesting is the balance between produced and natural capital. In poor countries, natural and produced capital were much more evenly balanced than in rich countries, consistent with the MA’s findings. The poor were more heavily dependent on – and more impacted by – changes in the quality and quantity of environmental assets. The most recent data show that the gap between gross national savings and adjusted net savings is highest in low- and middle-income economies.
Source: World Bank (2005)
And when these last two categories are broken down by region it becomes clear that the problem is particularly acute in three areas: the Middle East, Central Asia and Sib-Saharan Africa.
5. The value of ecosystem services and conservation incentives
So let me finally come back to the problem of the link between the value of biodiversity and ecosystem services and the effort that is committed to conserve them. Recall Geoffrey Heal’s comment cited at the start of this talk:
‘If our concern is to conserve these [ecosystem] services, then valuation is largely irrelevant. Let me emphasise this: ^ We conserve much that we do not value, and we do not conserve much that we value.’ (Heal, 2000).
I suggested then that what this says is that if we look at the current pattern of conservation around the world it does not correspond very well with what we understand about the economic value of ecosystem services or biodiversity. Should it do so? I suggested that the answer to that is unambiguously ‘yes’.
There are two problems to be solved. The first is the problem of local market failure, and is associated with the local public goods protected by local conservation effort. The second is the problem of international market failure, and is associated with the global public good protected by the international conservation effort. Both require the development of incentives to decision-makers to take the full costs of their actions into consideration, institutions for the regulation of access to biological resources, and an appropriate financial mechanism. These incentives should bear some relation to the marginal social value of the activities they are intended to encourage or discourage.
The incentive problem has two elements. One is the generation of the correct incentives for biodiversity conservation. The other is the discouragement of perverse incentives that work against conservation. At the international level, the incentive problem requires institutions that will enable host countries to ‘capture’ the global values associated with national biodiversity protection. Existing institutions include both a set of multilateral environmental agreements of which the CBD is pre-eminent, and a financial mechanism, the GEF. Other emerging institutions include joint implementation, bioprospecting contracts, global overlays, environmental funds and debt-for-nature swaps.
While the CBD is critical to the development of new biodiversity institutions and mechanisms, there is limited scope for solving the problem of biodiversity loss through international agreements of that type. For biodiversity conservation efforts to increase, the locally capturable return to investment in biodiversity conservation will have to improve. That requires market-like mechanisms that make it possible to exploit the potential gains from trade in the benefits of biodiversity conservation.
One major difficulty is that globalisation means the closer connection of economies and ecosystems around the world, but while liberalization of world trade – the object of successive rounds of GATT negotiations – has brought many benefits it has also increased international environmental risks, especially the risks of invasive species and the risks of infectious diseases (Perrings, Williamson and Dalmazzone, 2000). The growth in the world trade system (Figure 5) has increased both the number of pathways between ecosystems, and the volume of movements along both new and existing pathways. Both things increase the risk of biological invasions, by increasing the risks of new introductions and repeated introductions.
Trade liberalisation without attention to the environmental effects of trade makes the problem worse. For example, Copeland (2000) shows that if a trade agreement is not linked to any environmental agreement, it will induce a non-cooperative game in environmental policy. The result is feared to be a race to the bottom – implying a competition to set environmental standards below those of the trading partner.
This means that a necessary part of the reform of the global system of governance is that GATT negotiations should include scientific advice as to the potentially adverse environmental consequences of changes in the trade regime, and that where this shows significant negative environmental effects, side agreements addressing those effects should be in place before the general trade agreement is reformed. It is not sufficient to rely on the ex-post protection offered by the Sanitary and Phytosanitary agreement and Article XX of the GATT.
Trade liberalisation and trade growth without mechanisms or agreements to deal with Source: World Bank 2004, World Economic Indicators.
My final point is that the targeting of conservation incentives should reflect the relative value of ecosystems and the services they provide, and this in turn should reflect their relative scarcity. The scarcity of rare endemic species has historically led to the targeting of biodiversity hotspots. By enhancing our understanding of the value of ecosystems in the production of goods and services generally, we can identify the many other areas where ecosystem services are becoming increasingly scarce, and so should attract relatively more conservation effort. Whilst understanding the value of ecosystem services may be beyond the reach of economists (it requires the combined skills of ecologists, geneticists, chemists, hydrologists, geophysicists, psychologists and a host of others), it is the economists’ notion of value that should drive our collective decisions on what to conserve, and where. To repeat what I said at the outset:
We need both to understand what we lose when we lose biodiversity and ecosystem services, and we need to use this knowledge to better target our conservation efforts.
Экономическая оценка потери биологического разнообразия:
значение функций экосистемы
Статья посвящена проблемам снижения ценности экосистем и их биологического разнообразия. Экосистемы – наш естественный капитал – лежат в основе жизни как таковой. Многие экономисты в течение длительного времени задавались вопросом: почему изменяется экономическая величина фондов окружающей среды?
Необходимо понять, что мы утрачиваем в процессе потери биологического разнообразия и сокращения функций экосистемы (ecosystem services), и нужно использовать эти знания для координации мер по их сохранению.
Основой решения поставленных в работе задач стало исследование цены и ценности товара или услуги. Было выявлено, что цена товара или услуги может включать её ценность для определённого покупателя. Для любой данной цены существует вероятность того, что есть люди, которые желают платить большую цену, но чье поведение не влияет на её уровень.
В результате исследования было установлено, что основной причиной потери биоразнообразия во многих частях мира является то, что рынки продовольствия и одежды, которые регулируют распределение ресурсов в сельском хозяйстве, лесоводстве и рыбном промысле, обычно не отражают издержки общества частной обработки земли и сельскохозяйственной специализации.
Учитывая то, что ценность определенных видов в определенных экосистемах определяется ценностью товаров и услуг, обеспечиваемых этими видами, условно можно различить два вида ценностей: используемые и неиспользуемые (или косвенно используемые) ценности. К используемым ценностям относят ценность, которую биологические ресурсы прямо или косвенно имеют для людей, а также потребление тех ресурсов или услуги, которые они обеспечивают. Они включают пищу, топливо, биохимический, генетический материал, медицинские и другие фармацевтические продукты. Косвенно используемые ценности включают ценность ресурсов, которые непосредственно не входят в потребление, но могут составлять основу производства других товаров или услуг. Неиспользуемые ценности – обычно те, которые включают потребление или использование третьими лицами.
В статье изучена зависимость между биоразнообразием, функциями экосистемы, и человеческим благосостоянием (рис. 1). Учитывается как прямая, так и косвенная ценность биоразнообразия, косвенная ценность работает через процессы экосистемы и включает другие типы функций экосистемы, считавшиеся ценными: снабжение, культуру, поддержку, регулирование.
Установлено, что в экономических условиях, биоразнообразие является эквивалентом портфеля активов, и общественные действия, направленные на сохранение биоразнообразия являются эквивалентом инвестирования в этот портфель.
Следует также отметить, что уменьшение биоразнообразия и сокращение количества функций экосистемы зависит от того, насколько богаты или бедны люди. Если принять во внимание эффект роста населения, он показывает, что уровень богатства во многих странах изменился в течение последних трех десятилетий (Таблица 1).
Таблица 1 – Показатели устойчивости для Китая и Южной Азии, 1965-1997 гг.
Были выделены две проблемы, которые нужно решить для сохранения экосистем. Первая – проблема провала локальных рынков, она связана с локальными общественными товарами. Вторая – проблема несостоятельности международного рынка и связана она с глобальными товарами. Обе требуют разработки стимулов для лиц, принимающих решения, учёта полных издержек их действий, организации учреждений для регулирования доступа к биологическим ресурсам, и разработки подходящего финансового механизма.
Установлено, что снятие торговых ограничений без учёта эффектов торговли на окружающую среду является проблемным. Например, если торговое соглашение не связано с любым соглашением по окружающей среде, то оно породит некооперативную игру в политике окружающей среды. Результата следует бояться, он может быть гонкой на дно – подразумевающий конкуренцию по установлению стандартов окружающей среды ниже торгового партнера.
Ю.В. Чорток, Т.В. Иващенко
1Charles Perrings, Dr., President of International Society for Ecological Economics.
© Charles Perrings, 2005
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