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Biodiversity is frequently thought of as synonymous with species diversity in wild lands, and biodiversity loss is frequently thought of as synonymous with the extinction of wild species. But biodiversity is much more than species diversity in wild lands, and biodiversity loss is much more than species extinction. Biodiversity is the variety of species used in both the production and consumption of goods and services. Examples include the ornamental plants, birds and animals that people use to enrich their lives, the variety of foods they use to enrich their diet, the mix of biofuels or biofibres used to support productive activities. It includes the genetic diversity of cultivated crops, of crop pests, of wild crop relatives, of weedy species. It includes the range of biotic disease agents that affect human, animal and plant health, and the species used to control disease such as traditional medicinal plants and the plants used as the source of modern pharmaceuticals.
NGC 1365 is a galaxy which has lately received a lot of attention from people studying the structure and dynamics of barred galaxies. This is not surprising since it is one of the best suited objects in the sky. We have obtained a number of long-slit spectra in the red region (Hα, [NII], [SII]) with the ESO 3.6 m (Lindblad and Jörsäter) and with the CTIO 4 m (Peterson) telescopes. In addition, a couple of Fabry-Perot Hα interferograms have kindly been given to us by G. Comte and Y. Georgelin. Some preliminary results are presented here. Fig. 1 shows the positions of measured velocity points. The digits along the vertical axis indicate distance from the nucleus in seconds of arc. The dashed line at P.A. 48 deg indicates the line of nodes as determined from photometry of the outer features of the galaxy (Lindblad 1978). An arbitrary isophote has been sketched to aid the orientation. The emission lines in the bar are surprisingly weak which is the reason for the scarcity of velocity points there. Fig. 2 shows a rotation curve based on the P.A. of the line of nodes of 48 deg and an inclination of 55 deg (Lindblad 1978). Only velocity measurements within 50 deg of the line of nodes have been used in this diagram in order to avoid large projection errors. The distance used is 20 Mpc. The spread is quite large indicating a significant amount of non-circular motion.
This paper reviews the evolution of the field of environment and development over the last two decades. I argue that a central concern of the field has been the relation between natural resource use, income and growth, under the institutional and market conditions that prevail in developing countries. Particular attention is paid to the demographic and other drivers of change in the asset base, the linkages between poverty, property rights and the allocation of natural resources, the valuation of environmental assets and investment of resource rents, and the development of policies for managing environmental externalities and environmental public goods. I consider how the balance between topics and the treatment of individual topics has changed over time, and indicate how the field might be expected to move in the future.
Biodiversity change is the biggest environmental problem of our time. It leads to much more than species extinctions, affecting the food we eat, the diseases we face, our vulnerability to fire and flood, and our ability to adapt to climate change. Our Uncommon Heritage explores the many dimensions of human-driven biodiversity change. It integrates ecology, economics and policy to examine the causes and consequences of changes in ecosystems, species and genes, and to identify better ways to manage those changes. It explores the place of biodiversity in the wealth of nations, the rights and responsibilities people have for natural resources at local, regional, national and international levels, and the challenges faced in protecting the common good at the global level. This is an important book for students and researchers in the fields of conservation and sustainability science, ecology, natural resource economics and management. It also has much to say to those engaged in international conservation, health, agriculture, forestry and fisheries policy.
My discussion of the areas in which we can, and should, collectively do better in the management of biodiversity change has so far focused on the gains we can make in efficiency rather than in equity. It has emphasized the quality of the information we generate on the nature and significance of biodiversity change, and the way we use that information to inform decisions in a world where we cannot know everything. It has distinguished between the kind of information needed to support mitigation and adaptation strategies, and the options for balancing the costs and benefits of precautionary action. It has also identified the instruments available to convert information on the effects of biodiversity change into signals to those who supply and those who demand non-marketed environmental public goods. It has not considered issues of fairness or justice. Yet our starting point – the report of the Brundtland Commission – placed issues of equity at the core of sustainable development. The Commission famously argued that: “Poverty is not only an evil in itself, but sustainable development requires meeting the basic needs of all and extending to all the opportunity to fulfil their aspirations for a better life. A world in which poverty is endemic will always be prone to ecological and other catastrophes.” It noted that the concept of sustainability necessarily implied a concern for equity between generations, and argued that the same concern logically extended to equity within generations. Specifically, it claimed that meeting the needs of this generation implied an assurance that the poor would receive their fair share of the resources required to sustain growth (World Commission on Environment and Development 1987).
The unknowns in the problem of biodiversity change
In summarizing the state of knowledge on biodiversity change in both natural and managed systems the major assessments (the Global Biodiversity Assessment, the MA, the IAASTD, and the Global Biodiversity Outlook) usefully clarified the limits of our current understanding of biodiversity change. They showed that our knowledge is still extremely patchy. We know much about changes in species richness and abundance for birds, for example, but little about many invertebrates. We have many data on the ecological consequences of biodiversity change in temperate grasslands, but relatively few on tropical forests. At the same time none of the assessments offers much insight into the value of one type of biodiversity change relative to another. In the opening chapters of Part II of this book I have considered what this means for the information needed to underpin management of biodiversity change. Chapter 8 considers the information requirements of the main management options, adaptation and mitigation, and what this means for the way we project the causes, consequences, and character of biodiversity change. In Chapter 9, I address the issue of valuation, and the challenges involved in generating information that can inform macro-economic policy.
In the best of all worlds, however, we will still be called on to make decisions on the basis of incomplete information. There are two dimensions to the problem of biodiversity change that complicate both calculation of what it costs society and development of options for its management: the irreversibility of some aspects of biodiversity change and the fundamental uncertainty that induces. For all practical purposes the extinction of species is forever. Its effects are unknown and unknowable at the moment it occurs. People undertaking activities that change either the survival prospects of a species or its range cannot imagine all possible consequences of their actions. Nor are they able to assign probabilities to the consequences they can imagine. Similarly, it is not possible to reverse the changes wrought by many invasive species, or to assess the potential costs and benefits of actions that irreversibly affect the future evolution of the system.
There has been a burgeoning interest in the sustainability of many current trends – consumption, economic and demographic growth, and environmental change among them. While the origin of the term sustainable development is usually given as the report of the Brundtland Commission, Our Common Future (World Commission on Environment and Development 1987), its roots lie much deeper than that. One of the main precursors to the Brundtland Report, Herman Daly’s Towards a Steady State Economy (Daly 1973), directly appealed to John Stuart Mill’s mid-nineteenth-century thoughts on the stationary state. Mill saw a less growth-oriented strategy as the key to preserving at least some part of the natural environment (Mill 1909). Yet to do no more than maintain average incomes in many developing countries aggregate income is required to grow at rates up to 3.5 percent a year (i.e. to match the population growth rate), and increasing average incomes requires aggregate income to grow at rates above that. As Malthus had observed at the close of the eighteenth century, the consequences of failure to maintain average incomes have historically been severe (Malthus 1999). The challenge given to the global community by the Brundtland Commission was not just to avoid Malthusian crisis through the degradation of the resource base, but also to eliminate poverty worldwide.
The Brundtland definition of sustainable development – “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” – refers to the capacity of a system to maintain a flow of services over time (World Commission on Environment and Development 1987). This is a systems-level property that implies something both about system stability and about the value of system assets over time. What matters for the Brundtland definition is the capacity of the system to continue to deliver benefits over the expected range of environmental conditions.
The causes of the market failures behind the decline in ecosystem services reported by the MA have already been identified. Chapter 5 paid special attention to the differences in the problem of externality at the national and international scales. At the national scale it was noted that the failure of market prices to signal the scarcity of environmental resources, and the failure of markets to supply public goods, are both problems that can be resolved by government action. The fact that national governments have sovereign power makes it possible to address market failures directly by allocating property rights and by extending the legal protection of species or habitats on private lands. It also makes it possible to develop nationally funded incentive schemes such as the US biodiversity offset and banking programs considered in some detail later in this chapter (Madsen, Carroll and Moore Brands 2010). It makes it possible to establish national agencies with responsibilities for the provision of environmental public goods such as habitat for rare and endangered species, clean water, environmental health protection, and so on. The fact that national governments have sovereign authority over the land and people within national jurisdiction means that they are able to cut the Gordian knot of open or ill-defined access. At the international level, however, both externalities and the supply of environmental public goods are altogether more difficult to address. There is no supranational sovereign authority capable of assigning property rights or levying the taxes needed to fund the provision of public goods.
Indicators of the importance of biodiversity change for human wellbeing
To understand what we lose from the extinction of some species and the genetic erosion of others requires that we understand how these species contribute to the wealth of nations. It is not enough to lament their disappearance. We need to be able to identify the consequences of their loss for human wellbeing. Just as it can be shown that the increasing abundance of cultivated and domesticated species enhances wellbeing, we need to be able show that the declining abundance of other species can have the opposite effect. There are currently few reliable indicators of the importance of biodiversity change for human wellbeing. Although we know quite a lot about the benefits that people obtain from exploiting particular groups of species, and about the ecosystem services that lie behind those benefits, we still do not have good measures of what society gains and loses from more general changes in species richness and abundance. The point was made in earlier chapters that while the MA was able to say whether the physical flows of ecosystem services had been enhanced or degraded in the last fifty years, it was unable to value the loss of cultural or regulating services relative to the gain in provisioning services. It was not able to say whether the trade-offs being made between ecosystem services were warranted, given the costs and benefits involved. Nor was it able to say whether the investments people have made in the conversion of ecosystems for the production of foods, fuels, and fibers has made us collectively richer or poorer.
States began to be established, and so two categories were made of the things which had been wrested away from early ownership in common. For some things were public, that is, were the property of the people (which is the real meaning of that expression), while other things were private, that is, were the property of individuals. Ownership, however, both public and private, arises in the same way . . . Two conclusions may be drawn from what has thus far been said. The first is, that that which cannot be occupied, or which never has been occupied, cannot be the property of any one, because all property has arisen from occupation. The second is, that all that which has been so constituted by nature that although serving some one person it still suffices for the common use of all other persons, is today and ought in perpetuity to remain in the same condition as when it was first created by nature . . . things which are called “public” are, according to the Laws of the law of nations, the common property of all, and the private property of none. The air belongs to this class of things for two reasons. First, it is not susceptible of occupation; and second its common use is destined for all men. For the same reasons the sea is common to all, because it is so limitless that it cannot become a possession of any one, and because it is adapted for the use of all.
What do we know about the role of biodiversity in the modern world? What are the effects of biodiversity change on the two-fifths of the terrestrial system that have been fundamentally transformed by humankind? While the shape of the Holocene extinction is familiar to many – certainly to all those who work in the biological sciences – the way in which changes in species abundance and richness affect human activities is not. Most biodiversity research has focused on natural systems, and not on the role of biodiversity in supporting the production of goods and services of value to people. Research on agro-biodiversity, for example, is a vanishingly small proportion of total agricultural and forestry research. There are relatively few studies of the biodiversity in urban ecosystems, and almost no studies of the impact of changes in species diversity on ecosystem services in urban areas. The literature on biodiversity and health is primarily concerned with the role of species diversity in affecting disease transmission in natural ecosystems. The literature on invasive species is more broadly concerned with the impact of invaders on both managed and unmanaged systems, but it too focuses on the role of invaders in disrupting existing, functioning systems. The result is that we understand much about the ecology of biodiversity change, but little about its consequences for the production and consumption processes at the core of all human activity. Yet these are the things we need to understand if we are to understand directed biodiversity change.
I began writing this book in the small Galician town of Baiona where, on March 1, 1493, the arrival of the caravel Pinta from the Americas completed the initial stage of the Columbian exchange. It happens that I am back in Baiona as I write this final chapter – pulling together my conclusions about what it will take to redirect biodiversity change. I stated in the introduction to the book that this is by far the most significant environmental problem confronting humanity: that it dwarfs climate change; freshwater scarcity; soil, water, and air pollution; or any other of the environmental issues currently attracting attention. This is not due to any apocalyptic vision of the future, but to the observation that biodiversity change affects the quality of our lives in more ways, and more deeply, than any other environmental problem. The reason we are concerned about climate change, for example, is the effect it will have on life expectancy, health, and nutrition via its impacts on the species that determine these things. The reason we are concerned about freshwater lies in the importance of water for all of the species on which we depend. The reason we are concerned about pollution is the effect it has on the relative abundance of organisms in aquatic, terrestrial, and marine systems that directly support services we value.
Biodiversity change affects our ability to cope with the impact of changing environmental conditions. It may well be that our capacity to adapt to altered conditions is increased because of the scope for genetic engineering, but the scope for genetic engineering is itself constrained by the existing stock of genetic material in exactly the same way as traditional plant or animal breeding. Today’s biodiversity is what provides the raw material for the evolution of all life on earth, whether inside or outside the production landscapes we have made for ourselves. Our short-term interest lies in the scope biodiversity offers for success-ful adaptation to changing environmental conditions in the space of a generation or two. Given the fact that we happen to find ourselves at an unusually stable moment in the world’s climatic history, however, we also have a longer-term interest in maintaining our capacity to accommodate much greater environmental change.
The MA found that 60 percent of the ecosystem services evaluated had declined in the second half of the twentieth century (Millennium Ecosystem Assessment 2005). As Kinzig et al. have remarked, this should not have been at all surprising. The same 60 percent of services are unpriced in the market. We do not pay for them, and they generate no return to the landholders whose actions affect their supply. Since we get what we pay for, we should expect such services to be neglected (Kinzig et al. 2011). Indeed, this is only a problem if it imposes social costs we would prefer to avoid. The conclusion of the MA was that the physical changes it recorded were the socially undesirable consequences of the growth of markets for fuels, foods, and fibers. The external effects of market transactions, externalities for short, are the unintended or incidental consequences of the production or consumption of marketed goods and services. They may be positive or negative. The changes recorded by the MA would have been described by Crocker and Tschirhart as ecosystem externalities: market-driven actions that impact the wellbeing of either consumers or producers by altering the ecological functioning on which consumption or production depends, but where the welfare effects of those actions are ignored (Crocker and Tschirhart 1992). In what follows I refer to them as biodiversity externalities.
The drivers of the biodiversity loss recorded in the MA, and described in Chapter 2, define the most important of the biodiversity externalities. The expansion of land committed to agriculture or industry directly reduces habitat, and with it both species richness and abundance. The introduction of roads (and development along roads) leads to the fragmentation of habitat. While this may not immediately reduce species richness, the long-run effects are quite similar. The appropriation of water for human use in arid and semi-arid lands increases stress on other species, with direct effects on the abundance of those species. The accidental or deliberate introduction of invasive species through trade, transport, and travel frequently leads to the depletion of native species. Aside from these headline externalities, however, there are many more subtle stressors that also change biodiversity and the processes it supports.
The Brundtland Report made a strong connection between environmental change and poverty. It argued that since poverty was both a cause and an effect of global environmental change it was “futile to attempt to deal with environmental problems without a broader perspective that encompasses the factors underlying world poverty and international inequality” (World Commission on Environment and Development 1987). The report asserted that there was a positive feedback between poverty and environmental degradation:
Many parts of the world are caught in a vicious downwards spiral: Poor people are forced to overuse environmental resources to survive from day to day, and their impoverishment of their environment further impoverishes them, making their survival ever more difficult and uncertain . . . the poor and hungry will often destroy their immediate environment in order to survive: They will cut down forests; their livestock will overgraze grasslands; they will overuse marginal land; and in growing numbers they will crowd into congested cities. The cumulative effect of these changes is so far-reaching as to make poverty itself a major global scourge.
(World Commission on Environment and Development 1987)
It also noted the coincidence between poverty and species richness in the tropics, and identified the conversion of forest to agriculture in those regions as the primary cause of the loss of wild-living species. One implication of this is that by addressing the problem of poverty in the tropics, we can simultaneously address the problem of biodiversity loss.
Identifying the biodiversity-related multilateral agreements
Nation states are not the only bodies capable of securing international environmental public goods, but they are still the most important. The standard approach to the provision of environmental public goods that span national boundaries is through multilateral agreements between nation states. The primary multilateral agreement for biodiversity change is the Convention on Biological Diversity (CBD). However, the CBD is only one among many multilateral agreements concerned with biodiversity change. There are several global agreements addressing different aspects of biodiversity conservation. Aside from the CBD these comprise the Convention on Migratory Species (CMS), the Convention on International Trade in Endangered Species (CITES), the International Treaty on Plant Genetic Resources (ITPGRFA), the Ramsar Convention on Wetlands, and the UNESCO World Heritage Convention (WHC). All are associated through the Biodiversity Liaison Group.
But these agreements too are just the tip of the iceberg. The international environmental agreements database project lists 522 MEAs (plus 412 amendments and 196 protocols) signed in the last one hundred and fifty years, the earliest among them addressing the regulation of fisheries in the Rhine (1877) and the North Sea (1882, 1884), and measures to combat the phylloxera outbreak that devastated the vineyards of Europe in the late nineteenth century (1881, 1882). The list includes 255 agreements for the management of particular species or groups of species, 157 concerned with the conservation of flora and fauna, and 30 concerned with the conservation of landscapes, seascapes, and habitat (Mitchell, 2002–2012). Most of these agreements have been signed within the last fifty years, and nearly a third of all agreements, amendments, and protocols were signed during the 1990s (see Figure 13.1).