Biodiversity and Ecosystem Insecurity

A Planet in Peril

Ahmed Djoghlaf, Felix Dodds

• Publisher: Routledge
• Year: 2017
• Topic: Biological Sciences
• eBook ISBN:
  9781351573665
• Subtopic: Ecology
• Index: Biological Sciences

Biodiversity and Ecosystem Insecurity provides an authoritative and comprehensive assessment of the threats presented to human security and well-being by the loss of ecosystems and biodiversity recently confirmed as one of the critical 'planetary boundaries' that has already been exceeded. Contributors examine the current trends and state of biodiversity globally, the drivers of biodiversity loss including climate change and economic and population pressures, and the mechanisms and policies needed for conserving and restoring biodiversity in the future. Strong emphasis is placed throughout on the fundamental importance of placing a realistic economic value on nature and the services that ecosystems provide if we are to manage our natural resources successfully; and also on the crucial role of international institutions and government policies achieving this goal. As the recent high-profile meeting of the Convention on Biological Diversity in Nagoya, Japan, underlined, the scale and pace of the destruction of natural habitats and species imperil us all. This volume is an invaluable resource for conservationists, students and those in the private and public sectors concerned to redress the damage being done to the natural world.

Part I

Drivers of Biodiversity and Ecosystem Loss

1

What Are the Drivers Causing Loss of Biodiversity and Changes in Ecosystem Services?

Robert T. Watson and Peter Costigan

The Conceptual Framework of the Millennium Assessment (MA, 2003) distinguishes between different sets of driving forces that influence changes in ecosystems and their services and therefore also impact on human well-being. These include both direct and indirect drivers, and both exogenous and endogenous drivers. Understanding the different characteristics of these factors is an important step towards devising options for responding to the observed ecosystem change.

Biodiversity and ecosystem services are affected by both direct and indirect drivers. A driver is a natural or human-induced factor that directly or indirectly causes a change in ecosystem services. Direct drivers are those that directly impact on biodiversity and ecosystems, for example, land-use conversion, overexploitation, introduction of invasive species, pollution and climate change. Indirect drivers are those that influence the direct drivers of change, for example, economic and population growth resulting in an increased demand for food, fibre, water and energy and agricultural subsidies that promote increased agricultural production. Consequently, it is important to understand the relationship between the indirect and direct drivers of change, which can combine in different ways.

Decision-makers need to be able to identify the drivers that operate in a system in order to understand conditions and trends of ecosystem services, consequences for ecosystems and human well-being, and possible directions these trends might take in the future, and they also need to be able to identify response options. Understanding the factors that cause changes in ecosystems and their services is essential to the design of interventions that enhance positive and minimize negative effects. Each driver has a spatial and temporal scale over which it changes and over which it has an effect on ecosystem services and human well-being. Climate change may operate on the spatial scale of a large region; political change may operate at the scale of a nation or a municipal district. Social-cultural change typically occurs slowly, on a timescale of decades, while economic forces tend to occur more rapidly. Because of the variability in ecosystems, their services and human well-being in space and time, there may be mismatches or lags between the scale of the driver and the scale of its effects on ecosystem services.

Drivers, which are largely scale-dependent, can be controlled to varying degrees by decision-makers. Endogenous drivers are largely under the direct control or influence of a decision-maker. Exogenous drivers are largely beyond the direct control or influence of a decision-maker. The most common local-scale endogenous drivers are land use and land cover change, introduction of new technology and invasive species. Local-scale exogenous drivers are more varied, ranging from natural drivers (such as climate) to economic policy to infrastructure development. Drivers that are exogenous at one particular scale may be endogenous at another (usually coarser) scale. For example, prices for a particular commodity are usually an exogenous factor for a farmer that he or she has little control over, while a national government can influence the prices the farmer receives by regulating the market for this commodity.

Processes and structures can influence the effects of drivers on ecosystem services. These include natural phenomena as well as social, political and economic factors. The effect of an international trade agreement on food availability, for example, might be changed by national-level agricultural policies or the practices of local institutions.

Understanding drivers, their interactions and their consequences for ecosystem services and human well-being is crucial to the design of effective responses. Drivers often operate within sets of other drivers creating interwoven causal processes of ecosystem change. Causal processes of ecosystem change interact with each other, often in synergistic ways. Although many responses target specific problems with ecosystem services, the nature of complex systems means that such responses can have unintended consequences for the multiple interacting drivers that operate in the system and their effects on ecosystem services. Individual drivers may be difficult to affect without impacting on others, and therefore intervening in interactions between drivers is often a more direct way to achieve a desired outcome and enables a more integrated and holistic approach to ecosystem service management.

Actors that effect biodiversity and ecosystem services over a range of spatial scales need to work together, including:

1. Individuals and communities at the field level;
2. Public and private decision-makers at the local and national levels; and
3. Public and private decision-makers at the regional (for example, the European Union (EU)) and international level, through international conventions and multilateral environmental agreements (for example, the Convention on Biological Diversity (CBD), Ramsar, Cites and the United Nations Framework Convention on Climate Change (UNFCCC)) and international trade agreements (for example, the World Trade Organization (WTO)).

Many of the changes in habitats and their associated ecosystem services around the world are a result of satisfying the increased demand for the provisioning services of food, water, fibre and energy at the expense of biodiversity and regulating, cultural and supporting services. The increase in food production (crops and meat) has outstripped increases in the global population in the past 50 years by converting native forests and grasslands to arable and pastoral land, hence food per capita has increased. However, this increase in food production was associated with major declines in diversity and numbers of plants, terrestrial invertebrates and vertebrates, as well as a wide range of regulating, cultural and supporting ecosystem services. Increases in fishing harvests have resulted in 25 per cent of the oceans being overfished and another 50 per cent were at their maximum sustainable limits.

The key indirect drivers of change, which have resulted – and are projected to continue to result – in significant positive and negative changes to habitats and human well-being throughout the world, are:

• Economic growth: national and per capita income, macro-economic policies, international trade and capital flows. World gross domestic product (GDP) is currently about US$58 trillion with the following distribution: EU 28 per cent, US 25 per cent, Japan 8.8 per cent, China 8.5 per cent, Brazil 2.6 per cent, and India 2.2 per cent. Per capita increases in GDP between now and 2030 are projected to be largest in developing countries, for example, China more than 200 per cent, India around 175 per cent, US/Canada around 50 per cent, Western EU around 60 per cent. These projected increases in per capita GDP should enable a reduction in poverty in Asia, but coupled with an increased demand for water, biological and energy resources, that places increased pressure on all ecosystem services. Changes in world trade policies – for example, agricultural subsidies – will also impact on ecosystem services.
• Demographic changes: population size, age, gender structure and spatial distribution. World population is currently about 6.8 billion people with the following distribution; Asia 60 per cent, Africa 15 per cent, Europe 11 per cent, Latin America 8.5 per cent, North America 5 per cent, and Oceania around 0.5 per cent. The current annual rate of population growth has slowed to about 1.1 per cent, compared to about 2.2 per cent in 1963, but still equates to a population growth of 77 million per year. By 2050, world population is projected to range between 8 and 10.5 billion people, with a best estimate of about 9.2 billion, and the following distribution; Asia 57 per cent, Africa 22 per cent, Europe 7.6 per cent, Latin America 8 per cent, North America 5 per cent, and Oceania around 0.5 per cent. The largest changes in regional distribution are projected to occur in Africa, where a doubling of population is projected in some regions, including the region that today has the greatest poverty and the greatest reliance on ecosystem services. These changes in population will also be accompanied by increasing life expectancy and an aging population.
• Advances in science and technology: investments in research and development; crop and livestock breeding and species selection; and rates of adoption of new technologies, for example, biotechnology, Global Positioning Systems (GPS), information technology. Advances in genomics should provide the basis for improved crop traits – such as, drought, temperature, salinity, pest resistance and nitrogen-use efficiency – using classical plant breeding and genetic modification. Such advances should assist in reducing the projected loss of agricultural productivity due to human-induced climate change, and meeting the 50–70 per cent projected increased demand between now and 2050, through intensification rather than extensification, thus protecting critical habitats and their ecosystem services. Mechanization of farming practices and drainage technologies; use of agro-chemicals, such as fertilizers and pesticides; mechanization of fishing practices and sonar technology; and energy production have been key drivers of ecosystem change.
• Socio-political: governance and policies (for example, democratization); role of women, civil society organizations and the private sector. Governance and policies, which are sensitive to institutional settings, have significant implications for ecosystem services. For example, in southern Africa a trend towards democratization and increased participation can be observed in some countries, yet non-transparent and corrupt policy systems remain in power in others. Trends towards democratization are often associated with market-oriented economies. An economic regime shift due to changes in political structures can also be observed, for example, when a country joins the EU the introduction of EU policies has often led to major shifts in the agricultural production system. Cooperation rather than competition among actors involved in resource management can lead to improved cooperation for sustainable ecosystem management. Empowerment of women, who play a critical role in agricultural systems in many developing countries yet often have no access to finance, property rights, education and gender-sensitive extension services, could contribute to more sustainable agricultural systems.
• Behaviour change: individual choice (for example, consumption patterns, changing diets) and environmental attitudes. Consumer patterns are changing in two ways: first, consumers in developed countries want to eat fruit and vegetables all year round rather than those that are locally sourced in season, placing pressure on ecosystems around the world; and second, increasing wealth in developing countries is leading to an increase in the demand for meat, which significantly increases the resources needed for agriculture.

These in turn have caused:

• Conversion and fragmentation of natural habitats: Human land-use, and agriculture in particular, are important human activities converting natural ecosystems, especially grasslands and forests, resulting in a range of declines in species and populations. This is particularly important when the areas converted are high in species richness or endemism. Globally, the area of cropland is still growing in more than 50 per cent of all countries, although rates of growth are slowing. Meat production is increasing and has grown at an average of about 1–2 per cent per year over the past 50 years. The areal extension of domesticated land (cropland and pasture) over the 20th century ranges from 70 per cent to 80 per cent, and presently increases at a rate of about 0.2 per cent per year. Global round-wood production is the second major field of anthropogenic interference into the world’s ecosystems. Forest cover is estimated to have been reduced by about 40 per cent since industrial times and deforestation currently continues at about 15 million hectares annually. Other habitat types, such as tropical, subtropical and temperate grasslands, savannas and shrub-lands have experienced even greater losses.
  Habitat fragmentation can be caused by human-induced land-use changes (for example, clearing natural vegetation for agriculture or road construction) and natural disturbances (such as fires). Small fragments of habitat can only support small populations of rarer species, which therefore tend to become susceptible to extinction. Species that are specialized to particular habitats and those with poor dispersal ability are more adversely affected than generalist species and those with good dispersal ability. About 60 per cent of the world’s large riverine ecosystems are highly or moderately fragmented by dams, inter-basin transfers or water withdrawal, resulting in the decline or loss of species and ecosystem services. An increasing pressure that is emerging is the demand for land for production of biomass and biofuels. This is already occupying large areas of land and there is strong pressure to increase the coverage worldwide, in competition with other land uses such as agriculture and natural and semi-natural vegetation. This is likely to have a large effect on habitats.
• Overexploitation, especially associated with overfishing in the marine environment, animals hunted for bush-meat, and plants and animals harvested for the medicinal and pet trade: Commercial marine fisheries have in many parts of the world maximized short-term production beyond sustainable levels. This overexploitation has a significant adverse impact in marine ecosystems, both on target species but also on non-target species through wider ecosystem changes. Marine fish populations and communities have changed significantly since the 1960s, with exploited populations declining in abundance. The most vulnerable species are slow-growing and slow-breeding species such as groupers, croakers, sharks and skates, but many prey species are decreasing in average size, as younger cohorts are exploited. Evidence suggests that many marine populations do not recover from severe depletion even after cessation of fishing. After very marked increases in global fish landings up to about 1990, with a fourfold increase since 1950, landings have been relatively stable since then. The UN’s Food and Agriculture Organization (FAO) estimated that, in 2007, about 28 per cent of stocks were suffering from excess fishing pressure and 52 per cent of fisheries were at their maximum sustainable limits. Over exploitation of bush-meat is occurring in many developing countries with tropical forests because of extremely high offtake rates, with gorillas, chimpanzees and elephants being particularly vulnerable.
• Introduction of exotic invasive species: Improvements in transportation and globalization have resulted in an increase in both the purposeful (for example, for hunting or biological control) and accidental introduction (e.g. introduced with traded goods or in ballast water) of non-native species. When invasive alien species (IAS) become established – such as in the case of zebra mussels and water hyacinths – they can cause significant ecological, physical and economic damage. IAS can threaten native species as direct predators or competitors, as vectors of disease or by modifying the habitat. IAS have been a major cause of extinctions, especially on islands and in freshwater habitats. While the potentially adverse implications of IAS are well-recognized, the rate of introductions continues to be high and implementation of effective preventive measures are largely lacking. Because of the often non-linear responses to alien species, it can be difficult to quantify the risk they pose for biodiversity. Research has documented about 11,000 alien species in Europe, of which 1094 have documented ecological impacts and 1347 have documented economic impacts (Secretariat of the Convention on Biological Diversity, 2010)
• Pollution of air, land and water, especially nitrogen from the use of fertilizers and sulphur from the combustion of fossil fuels: The emissions of sulphur dioxide (SO₂), for example, were responsible for most of the acidification trends observable in the 1970s and 1980s in Europe and North America and now in large regions in Asia. Sulphate aerosols are also major constituents of, in particular, small aerosol particles, having a major climate effect (g...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Table of Contents
• List of Figures and Tables
• Foreword by Achim Steiner
• Foreword by Ryu Matsumoto
• Preface
• List of Contributors
• List of Acronyms
• Part I Drivers of Biodiversity and Ecosystem Loss
• Part II Biodiversity Insecurity
• Part III Climate Change Biodiversity and Ecosystems
• Part IV Governing Biodiversity
• Index