Using diatoms to assess the impacts of prehistoric, pre-industrial and modern land-use on Danish lakes

The impact of contemporary agriculture on Danish lakes is acknowledged to be extreme. In particular, high loading of nutrients from agricultural soils contributes to the eutrophic conditions found in many of Denmark’s lakes. Palaeolimnological studies have shown that human disturbance of the Danish landscape since the introduction of agriculture around 6,000 years ago has had a major impact on lake ecosystems. The European Union’s Water Framework Directive requires an evaluation of reference conditions for lakes, the conditions expected with only minimal human impact. Monitoring data and palaeolimnological studies of Danish lakes demonstrate that many of the most detrimental effects of eutrophication have been experienced in recent decades. A new study has suggested that the reference status for Danish lakes may be set to the status in ad 1850–1900, probably providing attainable, realistic restoration targets for many sites. The aims of this study were to explore the impacts of past and contemporary land-use on Danish lakes, and to consider how appropriate the use of 1850 as a date to define reference status is for these sites. Catchment land-cover data for ad 1800, taken from historical maps, and sedimentary diatom assemblages of the same age, from dated sediment cores, were used to assess the impact of pre-industrial land-use on 20 Danish lakes. Analysis of contemporary land-cover data and surface-sediment diatom assemblages for the 20 sites was also made. In-lake total phosphorus (TP) concentrations were estimated using the sedimentary diatom assemblages and an existing calibration dataset for Danish lakes. The percentage of the lake catchment that was agricultural land in ad 1800 explained 8.8% of the total variation in the diatom data. The land-cover variables ‘built-up areas’ and ‘plantations’, together explained 16.9% of the variation in the diatom data for the modern samples. Diatom-inferred TP concentrations were high for both ad 1800 (mean 112 μg TP L⁻¹) and the present (mean 122 μg TP L⁻¹), the latter estimates reflecting efforts in recent decades to reduce nutrient loading to Danish lakes following very high levels of nutrient enrichment post-1950. The data presented highlight the impact that human activities 200 years ago, particularly agriculture, had on Danish lake systems. The long cultural history and major anthropogenic disturbance of the Danish landscape mean that true reference conditions for lakes (or ‘baseline’ conditions, those found prior to human impacts) can be found only by considering century to millennial timescales.     

Strategic assessment of the magnitude and impacts of sand mining in Poyang Lake, China

Planning for the extraction of aggregates is typically dealt with at a case to case basis, without assessing environmental impacts strategically. In this study we assess the impact of sand mining in Poyang Lake, where dredging began in 2001 after sand mining in the Yangtze River had been banned. In April 2008 concern over the impact on the biodiversity led to a ban on sand mining in Poyang Lake until further plans could be developed. Planning will require consideration of both sand extraction in relation to available sediment resources and also environmental impacts within the context of future demand for sand in the lower Yangtze Valley. We used pairs of near-infrared (NIR) Aster satellite imagery to estimate the number of vessels leaving the lake. Based on this we calculated a rate of sand extraction of 236 million m³ year⁻¹ in 2005–2006. This corresponds to 9% of the total Chinese demand for sand. It qualifies Poyang Lake as probably the largest sand mining operation in the world. It also indicates that sand extraction currently dominates the sediment balance of the lower Yangtze River. A positive relation between demand for sand and GDP, revealed by historic data from the USA, suggests that the current per capita demand for sand in China might increase in the near future from 2 to 4 m³ year⁻¹. We review various environmental impacts and question whether it will be possible to preserve the rich biodiversity of the lake, while continuing at the same time satisfying the increasing Chinese demand for sand. Finally we review alternative options for sand mining, in order to relieve the pressure from the Poyang Lake ecosystem.     

Agroforestry in the Western Ghats of peninsular India and the satoyama landscapes of Japan: a comparison of two sustainable land use systems

Agroforestry in the Western Ghats (WG) of peninsular India and satoyama in rural Japan are traditional land-use systems with similar evolutionary trajectories. Some of their relevance was lost by the middle of the twentieth century, when modern agricultural technologies and urbanisation engineered shifts in emphasis towards maximising crop production. There has been, however, a resurgence of interest in traditional land-use systems recently, in view of their ability to provide ecosystem services. Both agroforestry and satoyama are thought to be harbingers of biological diversity and have the potential to serve as “carbon forests.” Carbon (C) stock estimates of the sampled homegardens in WG ranged from 16 to 36 Mg ha⁻¹. Satoyama woodlands owing to variations in tree stocking and management conditions indicated widely varying C stocks (2–279 Mg ha⁻¹). Agroforestry and satoyama also differ in nature, complexity, and objectives. While agroforestry involves key productive and protective functions, and adopts ‘intensive management’, the satoyama woodlands are extensively managed; understorey production is seldom a consideration. Differences in canopy architecture (multi-tiered structure of agroforestry vs. the more or less unitary canopy of satoayama) and land ownership pattern (privately owned/managed agroforestry holdings vs. community or local government or privately owned and mostly abandoned satoyamas) pose other challenges in the transfer and application of knowledge gained in one system to the other. Nonetheless, lessons learnt from satoyama conservation may be suitable for common pool resource management elsewhere in Asia, and aspects relating to understorey production in agroforestry may be relevant for satoyama under certain scenarios.     

Estimation of the nutrient inputs into river systems – experiences from German rivers

The nutrient discharges from point and diffuse sources in more than 200 German river basins were estimated for the periods 1983–1987 and 1993–1997 employing the MONERIS model. This model distinguishes between six diffuse pathways and point source emissions from waste water treatment plants and direct industrial discharges. It was estimated that the total nitrogen input into the German river systems amounts to about 819,000 t N year^–1 in the period 1993 to 1997. These emissions have decreased since the mid-eighties by about 266,000 t N year^–1, mainly caused by the reduction of point discharges. For phosphorus the emissions have been reduced by 56,290 t P year^–1 and amount to 37,250 t P year^–1 in the period 1993–1997. Based on emission data a retention module estimates riverine nutrient loads. The comparison of the model output with the observed loads shows a deviation as low as 30% and 50% for nitrogen and phosphorus, respectively. The regional resolution of the model indicates the relative importance of different pathways for phosphorus and nitrogen input into river systems. Electronic Publication     

Applications of a hydro-biogeochemical model and long-term simulations of the effects of logging in forested watersheds

We simulated hydrological and biogeochemical responses to logging in a forested watershed to determine the vulnerability and/or resiliency of the forest ecosystems in the Lake Shumarinai Basin in northern Hokkaido, Japan. We used a biogeochemical model (PnET-CN) and a rainfall–runoff model (HYCYMODEL) to predict ecosystem responses. The PnET-CN model simulated well the observed NO₃ ⁻ concentrations in streamwater, particularly at high concentrations during snowmelt; however, the model could not simulate small increases in NO₃ ⁻ during the summer. By considering hydrological processes within the watershed and combining the model with the HYCYMODEL (PnET + HYCYMODEL), the seasonality of streamwater NO₃ ⁻ concentrations was better simulated. Using these models, the long-term effects of logging were simulated for coniferous, deciduous, and mixed forests. NO₃ ⁻ concentrations in streamwater increased in response to the logging disturbance in both coniferous and deciduous forests. In the coniferous forest, NO₃ ⁻ concentrations reached a maximum 10 years after logging, and high concentrations persisted for 30 years. In contrast, NO₃ ⁻ concentrations in the deciduous forest reached a maximum within 3–4 years and recovered to pre-disturbance levels after 15 years. We also used the models to determine the effects of different sizes and types (coniferous, deciduous, and mixed forest) of logging areas on Lake Shumarinai. The model results indicated that large areas of cutting require more than 100 years for complete lake recovery. Whereas the annual discharge to the lake minimally increased, the annual NO₃ ⁻ load greatly increased. Our simulation results elucidate the vulnerability and resiliency of forest ecosystems and provide valuable information for ecosystem management.     

Modelling bark beetle disturbances in a large scale forest scenario model to assess climate change impacts and evaluate adaptive management strategies

To study potential consequences of climate-induced changes in the biotic disturbance regime at regional to national scale we integrated a model of Ips typographus (L. Scol. Col.) damages into the large-scale forest scenario model EFISCEN. A two-stage multivariate statistical meta-model was used to upscale stand level damages by bark beetles as simulated in the hybrid forest patch model PICUS v1.41. Comparing EFISCEN simulations including the new bark beetle disturbance module against a 15-year damage time series for Austria showed good agreement at province level (R2 between 0.496 and 0.802). A scenario analysis of climate change impacts on bark beetle-induced damages in Austria’s Norway spruce [Picea abies (L.) Karst.] forests resulted in a strong increase in damages (from 1.33 Mm3 a⁻¹, period 1990–2004, to 4.46 Mm3 a⁻¹, period 2095–2099). Studying two adaptive management strategies (species change) revealed a considerable time-lag between the start of adaptation measures and a decrease in simulated damages by bark beetles.     

Human impacts on methane emission from mangrove ecosystems in India

This study deals with the emission of methane in relation to changing environmental conditions and human impact, in three mangrove ecosystems of south India. Time-varying fluxes of methane adopting the close chamber technique were used to estimate CH₄ emission from an unpolluted site (Pichavaram mangroves) and two polluted sites viz. (1) Ennore Creek mangroves (affected by fertilizer effluents and crude oil discharges) and (2) Adyar estuary mangroves (affected by the discharges of organic and industrial wastes), covering monthly and seasonal variations. The results indicate annual average CH₄ emissions of 7.4, 5.02 and 15.4 mg m⁻² h⁻¹ from the sediment–water interface of the Pichavaram, Ennore Creek and Adyar estuary respectively. Emission characteristics obtained at Pichavaram mangroves represent a natural variability with changing physico-chemical factors, whereas the emission characteristics at Ennore Creek and Adyar estuary mangroves show anthropogenic influence. Several environmental factors such as oxygen availability, organic matter, soil physical and chemical properties, in addition to human-mediated interventions have been identified as influencing emission rates in the mangrove ecosystems. Preliminary CH₄ emission estimates for the mangrove ecosystems along the Indian sub- continent and the tropical and subtropical coastline of the world by linear extrapolation based on surface area range from 0.05 to 0.37 and 2.8 to 19.25 Tg CH₄ year⁻¹ respectively. Our results also highlight the impact of human activities on future emission of methane from the mangrove ecosystems. Received: 3 March 1999 / Accepted: 14 September 1999     

Fuelwood consumption in two tribal villages of the Nanda Devi Biosphere Reserve of the Indian Himalaya and strategies for fuelwood sustainability

Fuelwood is the only important source of energy in the mountainous region of the Garhwal Himalaya, India. Since the commercial source of energy is generally beyond the reach of ordinary people due to their poor socio-economic conditions and due to limited supply and lack of communication facilities for transport of LPG, the villages of the inner region of the Garhwal Himalaya depend on their fuel requirement from the forest. In the present study, two villages of the Nanda Devi Biosphere Reserve in Uttarakhand part of the Indian Himalaya i.e. Lata and Dunagiri located at 2,415 and 3,600 m altitudes, respectively, were selected for the study of socio-economic profile and vegetation and for estimation of per capita fuelwood consumption and the degree of disturbance. The study was conducted from 2002–2005. The population of these villages is migratory and belongs to the Bhotiya community, a scheduled tribe consisting of two subgroups known as Tolcha and Marchha. They grow traditional crops as well as cash crops. Important tree species used for fuelwood include Cedrus deodara, Pinus wallichiana, Cupressus torulosa, Taxus wallichiana, Acer indicum, Quercus dilatata and Viburnum cotinifolium. Maximum density among trees was shown by Pinus wallichiana (169.6 trees ha⁻¹) in village Lata and by Cedrus deodara (89.6 trees ha⁻¹) in village Dunagiri. The average per capita consumption of fuelwood in villages Lata and Dunagiri was 4.03 and 4.77 kg capita⁻¹ day⁻¹. Maximum number of trees (29 and 31% lopping for Lata and Dunagiri, respectively) belonged to disturbance class 1 (1–20% lopping) followed by the disturbance class 2 (20–40% lopping). Due to location of these villages in the buffer zone of the biosphere reserve, the fuelwood consumption may cause an adverse impact on the ecological status of this reserve, which urgently requires employing strategies for the conservation and management of this biosphere in terms of fuelwood sustainability e.g. regulation of livestock stock and grazing, using alternative sources of fuels, plantation of multipurpose trees and adoption of ecotourism.     

Soil carbon dynamics in a Mediterranean forest during the Kyoto Protocol commitment periods

The purpose of the present work is to asses the possibility of detecting changes in soil organic carbon (SOC) at the end of the 5-years of the first Commitment Period (CP) of the Kyoto Protocol of the United Nation’s Framework Convention on Climate Change (1 January, 2008–31 December, 2012), by both direct measurement and the use of an opportunely evaluated SOC model, CENTURY. The investigated soil is young, developed since 28 years on virtually C-free spoil banks and under the influence of two managed forest stands, one a mix of English oak (Quercus robur L.) and Italian alder (Alnus cordata Loisel.) and the other pure English oak. The SOC stock of either stand was monitored since the time the stands were planted in 1981, and it was used together with other parameters for the model evaluation, while the future projections for the end of the first (2012) and second (2017) CP were made according to two extreme IPCC climatic scenarios: A1F1, the most dramatic, and B2, among the less impacting. Direct SOC measurements performed at the beginning and at the end of a time frame equivalent to a commitment period (2004–2008) had not shown significant variations in either stands. Compared to the 2008 SOC stock, in both stands the model shows variations at the end of the first CP from 0.7 to 1.8 Mg C ha⁻¹ for the A1F1 scenario and from 0.3 to 1.7 Mg C ha⁻¹ for the B2. These variations are within the standard deviations of the C stocks measured in 2008. On the contrary, at the end of the second CP, the modelled SOC increments range from 2.5 to 3.6 Mg C ha⁻¹ (A1F1) or from 1.9 to 3.4 Mg C ha⁻¹ (B2), indicating the possibility to detect the SOC changes by direct measurement, since the values well agree with the minimum detectable variation estimated for both sites in 3.3–4.5 Mg C ha⁻¹. This work shows that SOC stock changes measured directly in the field can be minimal at the end of both CPs, and that CENTURY well simulates the SOC dynamics of the stands. The use of such a model, validated at long-term experimental sites, hence represents an effective tool for estimating future changes in SOC amounts in support of direct measurements when a short period of time, such as the CP, is considered.     

Contemporary changes in open water surface area of Lake Inle, Myanmar

From 1935 to 2000, the net open water area of Inle Lake in Central Shan State, Myanmar decreased from 69.10 to 46.69 km², a loss of 32.4% during this 65-year period. Local beliefs are that losses in lake area have been even greater within the last 100–200 years. Various activities, including timber removal, shifting agriculture in the uplands by various ethnic groups, and unsustainable cultivation practices on the low- and mid-level hillslopes around the lake, have been blamed for both historical and ongoing sedimentation. We take issue with attributing loss of lake area to these activities, and propose instead that ongoing “in-lake” and “near-lake” agricultural practices are the main sources of contemporary sediment and loss of open water area. About 93% (i.e., 20.84 km²) of the recent loss in open water area of the lake is due to the development of floating garden agriculture, largely along the west side of the lake. Direct environmental impacts associated with this practice and with other agriculture activities within the wetlands and margins of the lake include sedimentation, eutrophication, and pollution. Whilst the sustainability of hillslope agriculture and past forestry practices can indeed be questioned, a more urgent need is to address these "in-lake" and "near-lake" practices.     

Insularization and polymorphism in marginal island populations of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.

Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km² and increases to the level observed in the center of the range when the population area exceeds 50–100 km². A chorogenetic classification of marginal P. sylvestris populations is proposed.     

Relationship between morphological disparity and taxonomic diversity in rodent communities in the zone of influence from the Eastern Ural Radioactive Trace in the Southern Urals

To test the hypothesis that morphological disparity increases while taxonomic diversity decreases in a radioactively contaminated environment, the relationship of these parameters was studied in communities (taxocenes) of rodents living in the Southern Urals in the zone of influence from the Eastern Ural Radioactive Trace (EURT) (2003–2008). Young of the year of six rodent species (98 samples) were examined in the background (control) area (0.2 Ci/km²) and in the impact area polluted with radionuclides from the EURT (750 Ci/km²). The dynamics of morphological disparity (MD), assessed with regard to average values of five exterior characters, was compared between the control and impact taxocenes. Taxonomic (taxocenotic) diversity was estimated with the Shannon index (H). Morphological disparity was found to increase significantly at low rodent abundance (in conditionally unfavorable years) and decrease at high abundance, with the value of MD in the impact taxocene being significantly higher. A negative correlation between MD and H was revealed (r = −0.70), in conformity with the above hypothesis. Discordance (difference in direction) of annual changes in the test parameters, with H increasing while MD decreases (or vice versa) was observed in unfavorable years; it can be used as an indicator of conditions unfavorable for rodent taxocenes.     

THE FOREST–HYDROLOGY–POVERTY NEXUS IN CENTRAL AMERICA: AN HEURISTIC ANALYSIS

A ‘forest–hydrology–poverty nexus’ hypothesis asserts that deforestation in poor upland areas simultaneously threatens biodiversity and increases the incidence of flooding, sedimentation and other damaging hydrological processes. This paper uses rough heuristics to assess the applicability of this hypothesis to two montane forested countries in Central America: Guatemala and Honduras. We do so by using simple rules of thumb to identify watersheds at greater risk of hydrologically significant land use change, using information about land cover, slope, and watershed size. The location of these watersheds is compared to spatial maps of poverty and forests. We find plausible evidence for a forest–biodiversity–poverty connection in Guatemala, and to a lesser extent in Honduras.     

Optimum Supportable Global Population: Water Accounting and Dietary Considerations

In this paper we develop a novel, comprehensive method for estimating the global human carrying capacity in reference to food production factors and levels of food consumption. Other important interrelated dimensions of carrying capacity such as energy, non-renewable resources, and ecology are not considered here and offer opportunities for future work. Use of grain production (rain-fed/irrigated), animal product production (grazing/factory farm), diet pattern (grain/animal products), and a novel water accounting method (demand/supply) based on actual water consumption and not on withdrawal, help resolve uncertainties to find better estimates. Current Western European food consumption is used as a goal for the entire world. Then the carrying capacity lies in the range of 4.5–4.7 billion but requiring agricultural water use increase by 450–530% to 4725–5480 km³, the range based on different estimates of available water. The cost of trapping and conveying such water, will run 4.5–13.5 trillion over 50 years requiring an annual spending increase of 150–400%, straining the developing world where most of the population increase is expected. We reconfirm estimates in the literature using a dynamic model. ‘Corner scenarios’ with extreme optimistic assumptions were analyzed using the reasoning support software system GLOBESIGHT. With a hypothetical scenario with a mainly vegetarian diet (grazing only with 5% animal product), the carrying capacity can be as high as 14 billion. Ecological deterioration that surely accompanies such a population increase would negatively impact sustainable population. Using our approach the impact of ecological damage could be studied. Inter- and intra-regional inequities are other considerations that need to be studied.     

Irregularity in frequency of mast seed years in <Emphasis Type="Italic">Quercus floribunda</Emphasis> a late successional species of Central Himalaya

The mid altitudinal oak, Quercus floribunda forms predominantly evergreen forest in Central Himalaya between 2000–2400 m. It is late successional, mature phase species that has limited regeneration on disturbance prone sites. This oak produces mast seed crops at an interval of 2–3 years. During masting in Q. floribunda the seed fall and germination is upto ten times greater than in normal years, emphasizing the importance of mast year crop in forest maintenance. However, no mast year in this species since the last nine years (1997–2005) is a matter of serious concern. The rise in the summer and winter temperature over a period of 15 years appear to have affected the frequency of masting in this oak. The importance of masting can be adjudged from the fact that 97% of the surviving seedlings m⁻² are of the mast year crop.     

Intensification level of rice farming in Myanmar: implication for its sustainable development

This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P₂O₅; and potash, K₂O) ha⁻¹ (76–110 kg nitrogen (N) ha⁻¹), and the average paddy yield ranged from 2.8 to 3.5 ton ha⁻¹. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha⁻¹ (5 and 36 kg N ha⁻¹), and the yield ranged from 1.1 to 2.3 ton ha⁻¹. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha⁻¹ and 60 kg NPK ha⁻¹, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.     

Potentials and impacts of short-rotation coppice plantation with aspen in Eastern Germany under conditions of climate change

Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops: the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields. Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model 4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge, on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions of climate change, which increased from 7.47 t DW ha⁻¹ a⁻¹ under the recent climate to 9.26 t DW ha⁻¹ a⁻¹ at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha⁻¹ a⁻¹ under the recent climate and could rise up to 0.93 t C ha⁻¹ a⁻¹ under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations are a suitable contribution to regional CO₂ mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget are possible.     

An economic theory of reuse

An economic model of reuse is developed to analyse the effect of reuse activity on the amount of waste in the economy and the welfare of consumers. The paper adapts the theory of durable goods and second-hand markets. There is only one type of good, a durable good, which last two periods. A durable good is called ‘new’ in the first period and ‘used’ in the second period. Following Kim (Int Econ J 3:53–63, 1989), it is assumed that consumers differ in valuing the service rate of used goods. Their valuations are represented by a parameter θ, with a higher θ denoting consumers with a greater willingness to pay. In this study, high-θ consumers are referred to as reuse-friendly consumers. The new durable good is supplied in a competitive market. After the purchaser has used the good for one period, (s)he can sell it, keep it or throw it away. If a consumer decides to enter the second-hand market, (s)he has to pay a transaction cost. In equilibrium, the price of used goods will be determined endogenously by a second-hand market; it depends on the value of transaction costs. Thus, whether the second-hand market exists or not also depends on the value of transaction costs. It is shown that the amount of durable goods that is wasted is minimal when a second-hand market exists. When a second-hand market does not exist, increase in reuse-friendly consumers leads to decrease in the amount of waste. In the case of the second-hand market, when many consumers begin to reuse, the welfare of consumers who do not buy used goods will be improved.     

A stakeholder dialogue on European vulnerability

A stakeholder dialogue was embedded in the ATEAM project to facilitate the development and dissemination of its European-wide vulnerability assessment of global change impacts. Participating stakeholders were primarily ecosystem managers and policy advisers interested in potential impacts on ‘Agriculture’, ‘Forestry’, ‘Water’, ‘Carbon storage’, ‘Biodiversity’ and ‘Mountain environments’ sectors. First, stakeholder dialogue approaches to integrated assessment are introduced. Methodological considerations on stakeholder selection and dialogue implementation and evaluation follow. The dialogue content and process are evaluated from the perspectives of stakeholders and scientists. Its usefulness in the research process and the relevance of outcomes for stakeholders are particularly considered. The challenging compromises required to perform innovative research, which seeks to achieve both peer scientific credibility and societal relevance, are emphasized. Effective stakeholder dialogues play a substantial role in raising the visibility and meaningfulness of vulnerability assessments as critical means to improve awareness on global change and its potential worrying impacts on society. They further provide scientists with critical information on ecosystem management and sectoral adaptive capacity. These processes of mutual learning and knowledge exchange moreover foster a better understanding of the potential and limits of global change modelling and vulnerability assessment for policy and ecosystem management.

VALUING ECOSYSTEM SERVICES OF CHILEAN TEMPERATE RAINFORESTS

The Valdivian Rainforest Ecoregion (35°–48° S) in southern South America is among the ecosystems with highest conservation priority worldwide due to its rich diversity, degree of endemism, and critical conservation status. Temperate rainforests in this vast area are essential as source of biological resources and to maintain different ecosystem services which remain largely unmeasured and unvalued. Consequently, the benefits they provide are not reflected in decision-making regarding forest management and conservation. Based on existing studies and results from ongoing research we describe selected ecosystem services and provide estimates of their economic value. Timber benefits for secondary forests expressed as net present stumpage values were US$ 3742 ha⁻¹ and US$ 3093 ha⁻¹ for sustainable forest management (SFM) and unsustainable harvesting, respectively. Timber benefits for old growth forests␣equaled US$ 4546 ha⁻¹ and US$ 5718 ha⁻¹, for SFM and unsustainable harvesting, respectively, using an 8% discount rate. Annual benefits from recreation were US$ 1.6 ha⁻¹ and US$ 6.3 ha⁻¹ for the two most important national parks located in the study area. The annual value of maintaining soil fertility was US$ 26.3 ha⁻¹ using the replacement cost of nutrient losses due to soil erosion. The annual economic value of water supply for human consumption using the production function method was US$ 235 ha⁻¹. These results provide valuable information on the kind and magnitude of values that could be relevant in decision-making concerning conservation and management of native forests in the Valdivian Rainforest Ecoregion.