Senior fellow and contributing author, %people1%, comments in <i>Nature</i> on the release of the Millennium Ecosystem Assessment--a four year endeavour that explores the link between human well-being, the status of ecosystems and their sustainable use.

How can ecosystems provide sustainable services to benefit society?

Four years in the making, the Millennium Ecosystem Assessment (see Nature 417, 112-113; 2002) is released this week (starting 30 March). This gigantic endeavour explores the link between human well-being, the status of ecosystems and their sustainable use.

What has this assessment taught us about developing our planet, and will it, or should it, be continued? To answer the first part of this question, the assessment is an invaluable record of where we stand now, and why. But for it to be useful, the answer to the second part of the question must be 'yes'. We need to take a consistent approach to measuring the status and trends of the world's ecosystems. To take one example, the Convention on Biological Diversity has set the target of reducing the rate of global loss of biodiversity by 2010. But the data to evaluate whether this goal is being met are not readily available, as biological diversity is more than just an enumeration of species present or absent - it includes parameters such as the populations of species and the ecosystems in which they reside. In addition, biodiversity is just one of the many aspects of change in ecosystems and their related functions assessed in the Millennium Ecosystem Assessment. Only from a periodic audit of the state of our natural resource base can we determine if we are indeed approaching sustainability.

At present, there are no formal plans to repeat the Millennium Assessment. There should be, and we hope that the informal discussions among the current sponsors will bear fruit from the seeds sown by the many smaller, ongoing sub-global assessments that were stimulated by the assessment.

Achievements and goals

The Millennium Ecosystem Assessment took a new pathway of evaluating the status of the Earth's human support systems. Rather than the standard environmental audit, the new assessment places audits of numbers of organisms and so on into the context of how ecosystem changes have affected human well-being, and how they may do so in the foreseeable future. It had to find a link between the status of biotic systems and the status of individuals in various societies in the world to estimate the capacity of ecosystems to provide services that benefit society. Many of these links are obvious, but others have not been appreciated, nor have all these linkages been quantified. In essence, we had to make a large leap from the current styles of evaluations of status and trends in ecosystems to an entirely different approach - an ecosystems services database related to how ecosystems and societies operate, and how they interrelate.

Current status of ecosystems

Human societies have made marked progress in increasing provisioning services, such as crops and livestock, to meet the demand of a growing population (see Box 1). Food is more abundant and cheaper than in the past. Despite these dramatic accomplishments, there are still more than 850 million undernourished people, and some advances in production are at the cost of other services essential for human well-being, such as ocean fisheries, wood for fuel, genetic resources and - perhaps the most important - fresh water. It is the poor in many nations that are most directly dependent on services from ecosystems, and the degradation of these systems can exacerbate their poverty. Millions of people face the reality of the declining availability of cheap protein from local fisheries, inadequate water for sanitation or live on degraded landscapes.

There are a number of issues that cloud the goal of sustaining a high level of provisioning services. The use of fertilizer in agriculture has greatly increased to meet food demand, but at the cost of polluting off-site unmanaged ecosystems, such as groundwater, rivers and coastal fisheries. In many regions, water for irrigation is being pumped from groundwater and in some cases from fossil sources. Rivers are dammed and diverted for irrigation, altering ecosystems that depend on this water - causing the loss of many of the services they provided.

Further, we are diminishing crucial 'regulating' services responsible for climate, erosion, air- and water-quality control, as well as for the regulation of pests and natural hazards. We are losing these services due to massive land-surface conversion, atmosphere alteration, eutrophication, overharvesting and the impact of invasive species. The Millennium Assessment concluded that 60% of the ecosystem services evaluated were either being degraded or being used unsustainably.

As an example, cultivated systems (areas where at least 30% of the landscape is in croplands, confined livestock production or freshwater aquaculture) now cover a quarter of the Earth's surface, partly by conversion of temperate grasslands, Mediterranean-climate forests and many tropical ecosystem types. Forests have essentially disappeared from 25 countries, with 9.4 million hectares being lost annually from the Earth's surface. Historically important fisheries have collapsed or are overfished, one third of the mangrove forests for which there are historical data have been lost, as have 20% of the coral reefs, with a further 20% degraded. Nearly 40% of the rivers of the world have been fragmented. Species and populations of species are being lost at unprecedented rates, while at the same time the global biota is becoming homogenized owing to the introductions of alien species to new regions. These examples represent major losses of pieces of the biosphere machinery, which have a serious impact on the delivery of ecosystem-regulating services - impacts such as greater prevalence of infectious diseases in disrupted ecosystems, adverse effects on local climates by ecosystem modification, and the loss of flood protection (as in the recent tsunami in Indonesia).

What we can do

The drivers of change in ecosystems and their services will continue in direction and intensity. So how can these trends be reversed to achieve sustainability and to relieve the negative impacts of the loss of services to society, particularly to the disadvantaged? New pathways and approaches can and must be taken. But these are major initiatives, which will mean profound changes in the way global society operates. As learned in the Millennium Assessment, favourable responses need to take place at all levels, from the local to the global. Global mechanisms do not necessarily solve local problems, yet are an important part of the overall solution. At the same time, local players and solutions can feed into regional and global approaches. The players at these different levels address different decision-makers, who can collectively put in place the major changes that are needed for ecosystem sustainability.

The Millennium Assessment examines the merits of options for mechanisms and policies, to accomplish the goal of maintaining and enhancing the delivery of ecosystem services to society. Some of these require major reorganization in the way we do business. At present, our organizational structures address separately the issues of a single resource, such as agriculture, fisheries or the environment. There is little interaction within and between each issue, and much less again with trade and the treasury bodies. The lesson of the Millennium Assessment is that all these resource issues are interrelated: action on one issue has consequences for another. It is crucial to address how to minimize the trade-offs (biodiversity or clean water for agricultural yield), either on-site or by managing landscapes. One important example of how this process can work is the EU system of directives for nitrate accounting on landscapes.

Some institutional innovations are moving towards more integrated views of issues and responses to them. For example, Britain has a government department for Environment, Food and Rural Affairs. These are all closely interrelated domains, but in other countries are often handled by competing agencies. Elsewhere, interagency groups are evolving to address central issues such as climate change, but their effectiveness is hampered by competitiveness and politics. We need new kinds of institutions in better positions to achieve sustainability of ecosystems that provide for human well-being.

We must also try to improve the economics. Although provisioning services are enmeshed in the local (and increasingly global) marketplace, regulating services are not. We must accelerate our ability to value ecosystem-regulating services at the national level, as well as the ecosystem services that provide crucial cultural amenities, and ensure that these values are considered in decision-making.

Some progress is being made. Costa Rica has established a system of conservation payments, under which contracts are brokered between international and domestic 'buyers' and local 'sellers' of sequestered carbon, biodiversity, watershed services and scenic beauty. On a global scale, the Ecosystem Marketplace consortium is beginning to track transactions, pricing trends and buyers' requests on the carbon, water and biodiversity markets. It is predicted that the global carbon market will reach US$44 billion by 2010.

We need to eliminate the subsidies that promote the excessive use of ecosystem services and evaluate more carefully the trade incentives that damage ecosystem services. We must work harder to educate the public on the strong links between sustainable ecosystems and the lives of humans. The role of new technologies in more efficient use of natural resources is crucial and needs more incentives.

There is plenty that can and needs to be done to deal with the crisis that has already enveloped us. The path is open for scientists to quantify, to a much greater extent, the way in which the operation of ecosystems is directly linked to human well-being, and hence model the course of human activities on future outcomes of the delivery of these services. The Millennium Assessment is certainly providing a strong stimulus for such studies.

Millennium Assessment

Acknowledgements. We thank the scientists, reviewers and members of the review board who provided input to the Millennium Ecosystem Assessment, and the sponsors of this work.

When the 9.0-magnitude earthquake and resulting tsunami struck Asia and East Africa on December 26, Indonesia took a devastating hit. More than 100,000 people died and another 500,000 were left homeless, with some experts predicting that the final death toll may rise above 250,000. Aceh province on the northern tip of the island of Sumatra, where the Free Aceh Movement rebel forces have been fighting against the Indonesian Defense Forces for almost 30 years, was at the center of the destruction. Donald Emmerson, a senior fellow at the Stanford Institute for International Studies and director of its Southeast Asia Forum, is an Indonesia specialist who has been traveling to Aceh since the late 1960s. He's finishing a book entitled What is Indonesia? Identity, Calamity, Democracy.

STANFORD: What do we need to know about Aceh province?

That it's a wonderful place, that the people have a tradition of hospitality, and that they share with you what they have. It's very sad that it has been subject to so much violence and conflict for so many years.

What's been happening in recent times?

Since May 2003, Aceh has been virtually off-limits to foreigners. The [military] reasoning is that it's for security reasons, but there's always been a suspicion that it's also because bad things -- horrible things, killings and so forth -- are done in the dark, and they don't want people to watch. Certainly the human rights community has had great difficulty getting access to Aceh.

What could happen as a result of some 1,000 representatives of aid organizations being on the ground there?

The opening of Aceh to foreign and domestic humanitarian aid workers has the potential to introduce elements that can serve as a check on human rights abuses. Obviously, the time for mourning is not over. But if we can insert a silver lining in this very dark cloud, it might be that the devastation of the tsunami opens up an opportunity to rebuild much of Aceh, and that it will require cooperation among all Acehnese. I am cautiously optimistic about the opening that this catastrophe represents for trying to lessen the man-made pain of the Acehnese people.

What might a rebuilt Aceh look like?

The plan is to take villages that were destroyed, and maybe even the town of Meulaboh on the west coast, which was the worst hit, and move them inland a certain number of kilometers. Then, construct mangrove swamps as barriers against a repetition of the tsunami, and also to protect the soil from erosion and generate the possibility of brackish-water fishing for the livelihoods of the people. This is a massive effort that is going to last for years and years. Authorities have estimated that the rebuilding costs in Aceh could run to $2.2 billion.

Fishing villages would no longer exist on the coast?

I spent nine months in fishing villages in East Java, and I found that the relationship of the populations on the coast to the ocean is not necessarily what one would expect. They are not happy bathers on the beach, fishing is an extremely dangerous operation, and the ocean is considered a wild place.

Many fishing communities are overfishing the source. I wrote a long report for the Ministry of Agriculture's fisheries office, arguing that what Indonesia ought to do was take the money the government was spending to supply nylon fishing nets and higher horsepower outboard motors, and spend it on wives who were involved in craft commodities. The women have commercial skills, and getting microcredit programs for women to set up shops and expand is the future.

How will religion figure in that future?

Aceh is known in Indonesia as "the front porch of Mecca." The Acehnese are almost entirely Muslim. While there's a tendency among Americans to presume that [a Muslim nation] must be fanatic, Indonesia remains an overwhelmingly moderate society. There is a poignant photo, which hasn't been circulated in the U.S. press, of a sign at a depot for humanitarian relief supplies. It reads, "If you try to steal this material, you will be responsible to Allah."

The following is supplemental material that did not appear in the print edition of STANFORD.

What was the overall impact of the tsunami in Indonesia?

I think it's important to keep in mind that each of the affected countries was affected in a somewhat different way. In Sri Lanka, an estimated 70 percent of the coastline of the entire island was affected, so the economic consequences there are going to be more severe than the damage that was done to Indonesia. If you go down the west coast of Sumatra, you will see damage, but the main damage was overwhelmingly concentrated in a single province, Aceh, which represents less than 2 percent of the total population of Indonesia. Aceh got a double-barrel assault -- from the earthquake and the tsunami. The death toll was horrid, with a huge loss of life, but it was concentrated on the coasts.

How does Aceh's history set it apart from the rest of Indonesia?

The first record we have of an Islamic sultanate in what is now Indonesia is a stone carving dated 1297, on the north coast of Aceh. Aceh was closest to the Middle East, and there were Muslim traders who would go short distances, pause, sell, buy and reload. Long-distance Arab-Malay trade finally got to Indonesia, and the logical landfall was Ache.

Then there were tremendous and unequal casualties in the war against the Dutch, who recruited Ambonese troops to fight a colonial war in Aceh in the 19th century. There's a photograph of Dutch troops standing on the dead bodies of Acehese rebels. The Acehnese war lasted a long time, and it was one of the last parts of the archipelago to be fully brought into the colonial orbit.

Aceh has been for some time under a state of military emergency, and an estimated 13,000 have died as a result of the [rebel] war since 1976. But the tsunami has changed all that. Looking at it from a political science point of view, if we don't begin trying to analyze the situation, I'm not sure we can make it better down the road.

What needs to happen?

In a time of crisis what you need is efficiency and effectiveness, and you need somebody to stand up and say, "This is the way things are going to be." But the governor of Aceh is, by all accounts, exceedingly corrupt. He is in Jakarta now, in detention, awaiting trial on corruption charges. So you don't even have an active, sitting provincial government leader to take charge.

The number of members of the provincial administration who died in the tsunami is quite high, and the central government has had to send up 300 replacements from Jakarta. The administration of Aceh has essentially been completely taken over by the central government. This is potentially unhelpful, depending on how sensitive and effective the central government is and how corrupt the atmosphere is within which masses of foreign aid are moving.

The somewhat optimistic scenario is that now Aceh is even more dependent on the central government than it was before, with the need to rebuild substantial portions of its coastline. So a leader of the [freedom] movement [might] look down the road and say, "It's unrealistic for us at this point, with this incredible body blow to our economy, to expect that we can now somehow take over Aceh. We are more dependent than we were before on the central government."

And, conversely, in Jakarta there might be the thinking that since Aceh now so obviously needs support within the republic, "We are in a stronger position, and therefore we can afford to be generous, and to extend concessions, short of independence, that will take advantage of this." The bottom line is that two enemies who were at each other's throats now face a third enemy -- nature.

Are there other voices that should be heard in Aceh?

One of the difficulties of having negotiations between the Acehnese Freedom Movement and the central government is that it tends to exclude other Acehnese views, which is one reason why negotiations that took place previously were not successful. Acehnese society is pretty diverse, and the Acehnese Freedom Movement does not represent all Acehnese, not to mention the Javanese and Indonesians who have migrated into the province, who are university students and [members of] religious communities.

The conflict has lasted for 30 years in its present form, and it has created such enmities that there is no particular mood to compromise. The government has no incentive to reach out, and the Acehnese Freedom Movement remains intransigent. In the long run, those who disagree with a so-called freedom movement are in the shadows and their views tend not to be reported. My hope is that as these voices are allowed to take part in determining the future of Aceh and its political leadership, the polarization will decrease and there will emerge a kind of more moderate center, in favor of autonomy and full rights.

In the 1990s, the United States cut military assistance programs to Indonesia. Is the relationship between the two countries improving?

SBY -- Susilo Bambang Yudhoyono -- is a former military man, but he's identified as relatively clean, and associated with a somewhat more reform-minded element within the military. More than any previous president of Indonesia, he has had exposure to the United States. Certainly this is an opportunity for an improved relationship between Indonesia and the U.S.