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Two research projects were established to foster Brazilian-German collaboration and inter- and transdisciplinary research in the southern Amazon region. In the scope of the German BMBF-FONA program (Federal Ministry for Education and Research?Research for Sustainable Development), the Carbiocial consortium (www.carbiocial.de) investigated C stock changes, greenhouse gas (GHG) emissions, erosion, catchment hydrology, agricultural production, land cover, socio-economic drivers, policy impact and actor networks using experiments, monitoring, surveys, remote sensing and dynamic simulation modelling. In Brazil, the corresponding research project Carbioma focused more specifically on the political programs which were established to mitigate environmental problems arising from inappropriate land use, such as Brazil?s Sector Plan for the Mitigation and Adaptation to Climate Change for the Consolidation of Low Carbon Emission Agricuture (ABC Plan; Plano Setorial de Mitigação e de Adaptação às Mudanças Climáticas para a Consolidação de uma Economia de Baixa Emissão de Carbono na Agricultura; MAPA?MDA 2012), the Nationally Appropriate Mitigation Actions (NAMAS) and the intended Nationally Determined Contributions (iNDC; Brazil 2015). For this, Carbioma performed field experiments at the different experimental field stations of the Empresa Brasileira de Pesquisa Agropecuária (Embrapa). The main objective of both project consortia was to investigate viable, carbon-optimised land management strategies for this hotspot of global change research. Together with its Brazilian partners, collaborators and local stakeholders, Carbiocial concentrated on obtaining parameters for simulation models, which are then used to test and improve carbonoptimised land use management strategies Made available in DSpace on 2018-01-03T23:19:37Z (GMT). No. of bitstreams: 1 CNPAF2018recp1.pdf: 764290 bytes, checksum: a9c95ac8ad5e4d9cd58d70ae2ff20965 (MD5) Previous issue date: 2017-12-14

We analyzed changes in water quantity and quality at different spatial scales within the Tapajós River basin (Amazon) based on experimental fieldwork, hydrological modelling, and statistical time-trend analysis. At a small scale, we compared the river discharge (Q) and suspended-sediment concentrations (SSC) of two adjacent micro-catchments ( 2) with similar characteristics but contrasting land uses (forest vs. pasture) using empirical data from field measurements. At an intermediary scale, we simulated the hydrological responses of a sub-basin of the Tapajós (Jamanxim River basin, 37 400 km2), using a hydrological model (SWAT) and land-use change scenario in order to quantify the changes in the water balance components due to deforestation. At the Tapajós' River basin scale, we investigated trends in Q, sediments, hydrochemistry, and geochemistry in the river using available data from the HYBAM Observation Service. The results in the micro-catchments showed a higher runoff coefficient in the pasture (0.67) than in the forest catchment (0.28). At this scale, the SSC were also significantly greater during stormflows in the pasture than in the forest catchment. At the Jamanxim watershed scale, the hydrological modelling results showed a 2 % increase in Q and a 5 % reduction of baseflow contribution to total Q after a conversion of 22 % of forest to pasture. In the Tapajós River, however, trend analysis did not show any significant trend in discharge and sediment concentration. However, we found upward trends in dissolved organic carbon and NO3− over the last 20 years. Although the magnitude of anthropogenic impact has shown be scale-dependent, we were able to find changes in the Tapajós River basin in streamflow, sediment concentration, and water quality across all studied scales.

This article describes the design of a new model-based assessment framework to identify and analyse possible future trajectories of agricultural development and their environmental consequences within the states of Mato Grosso and Para in Southern Amazonia, Brazil. The objective is to provide a tool for improving the information basis for scientists and policy makers regarding the effects of global change and national environmental policies on land-use change and the resulting impacts on the loss of natural vegetation, greenhouse gas emissions, hydrological processes, and soil erosion within the region. For this purpose, the framework combines the regional land-use models, LandSHIFT and alucR, the farm-level model, MPMAS, and the MONICA crop model, with a set of environmental impact models that are operating at the regional and watershed levels. As a first application of the framework, four scenarios with the time horizon 2030 were specified and analysed. Future land-use change will strongly depend on the interplay between the production of agricultural commodities, the agricultural intensification in terms of increasing crop yields and pasture biomass productivity, and the enforcement of environmental laws and policies. On the regional level, the scenarios with the highest increase in agricultural production in combination with weak law enforcement (Trend and Illegal Intensification) generated the highest losses in natural vegetation due to the expansion of agricultural area as well as the highest greenhouse gas emissions. Also, at the watershed level, these scenarios are characterised by the highest changes in river discharge and soil erosion that might lead to a further decline in soil fertility in the long term. Moreover, the analysis of the Sustainable Development scenario indicates that a shift in agricultural production patterns from livestock to crop cultivation, together with effective law enforcement, can effectively reduce land-use change and its negative effects on the environment. With the scenario analysis, we could illustrate that our assessment framework is capable to provide a large variety of valuable information to support the development of future land-use strategies in the study region.

Ecuador is currently completing the readiness phase for the implementation of the Reducing Emissions from Deforestation and forest Degradation (REDD+) mechanism at the national level. Many challenges regarding rights, multilayered governance and land tenure remain open in this country where Indigenous Peoples (IPs) occupy 68% of the Ecuadorian Amazon. We focused on the Yasuni Biosphere Reserve to exemplify obstacles and answers found in the last years. In a REDD+ pilot project, six communities of the most widespread ethnicities (Shuar, Kichwa and Colonists) living in the buffer zone of the Yasuni National Park (YNP), were chosen. We used literature research, analysis of international and national agendas, as well as primary data on REDD+ perception obtained through semi-structured household interviews and personal observations. First, we reconstruct the historical development of territorial configuration and present the actual land tenure arrangements. And then, we analyze persistent management conflicts within institutional, planning and normative instruments. Finally we explore legal frameworks with a focus on participation and consultation. Our results show that insecure and overlapping land rights, as well as unclear and contradictory institutional responsibilities are major problems for REDD+ implementation. Despite great advancements that have been made, establishing equitable mechanisms to engage IPs and forest owners and stakeholders across many sectors in REDD+ is required. Especially in Ecuador where oil extraction is a priority and the central government has an exclusive competence over ecosystem services including carbon rights. Implementing fair methods for participation, benefit sharing and transfer of knowledge remains a challenge.

Studies on the impacts of land-use and land-cover change on stream hydrochemistry in active deforestation zones of the Amazon agricultural frontier are limited and have often used low-temporal-resolution datasets. Moreover, these impacts are not concurrently assessed in well-established agricultural areas and new deforestations hotspots. We aimed to identify these impacts using an experimental setup to collect high-temporal-resolution hydrological and hydrochemical data in two pairs of low-order streams in catchments under contrasting land use and land cover (native vegetation vs. pasture) in the Amazon and Cerrado biomes. Our results indicate that the conversion of natural landscapes to pastures increases carbon and nutrient fluxes via streamflow in both biomes. These changes were the greatest in total inorganic carbon in the Amazon and in potassium in the Cerrado, representing a 5.0- and 5.5-fold increase in the fluxes of each biome, respectively. We found that stormflow, which is often neglected in studies on stream hydrochemistry in the tropics, plays a substantial role in the carbon and nutrient fluxes, especially in the Amazon biome, as its contributions to hydrochemical fluxes are mostly greater than the volumetric contribution to the total streamflow. These findings demonstrate that assessments of the impacts of deforestation in the Amazon and Cerrado biomes should also take into account rapid hydrological pathways; however, this can only be achieved through collection of high-temporal-resolution data.

This study presents the setup, calibration, validation and scenario application of the soil and water assessment tool for two contrasting macro-catchments along the Amazon agricultural frontier in the federal states of Para and Mato Grosso, Brazil. Calibration and validation of the model are realised for the periods of the most intensive deforestation and agricultural expansion. In order to give consideration to the rapid, however gradual nature of land use change, the model implements an annual land use update combined with a land use dependent soil parameterization of the upper most soil layer. The comparison of these results with the results of a setup with a steady land use distribution shows distinct improvements of the prediction quality. Discharge prediction improves through the application of gradual land use change in the model by 12 % for a 1.8 % deforestation rate per year and 1.2 % for a deforestation rate of 0.7 % per year. Consequently, the validated models are applied to four land use scenarios for the period 2026–2035. Scenario simulation results show effects on the water balance proportional to land use change. Further, the changes in the water balance follow clear seasonal patterns with highest hydrological effects due to land use change during the rainy season in both catchments. Overall, with continuous deforestation, peak discharge increases. Further, the conversion of native vegetation to pasture has the highest impact on the water balance. For example, monthly discharge in the rainy season increases by up to 24 % for a 13 % conversion of Cerrado savannah into pasture.

International audience; AbstractKey messageShade trees in agroforestry systems protect the understory cocoa from climate extremes. Shade tree pruning manages microclimatic conditions in favor of cocoa production while tree diversity is maintained. Adaptation of pruning has to consider seasonal changes in temperature and precipitation to protect the understory cocoa.ContextStructural characteristics of tree stands such as species diversity, tree density, and stratification can affect throughfall and microclimate. Pruning changes the canopy and may therefore modulate internal conditions.AimsThe aim of this study is to assess the environmental growing conditions of cocoa trees.MethodsWe monitored canopy openness and the impact of stand structure on throughfall and microclimate in three cocoa production systems (monoculture, agroforestry, and successional agroforestry) and a natural regrowth in a long-term trial in Bolivia from 2013 to 2015. We further focused on the effect of annual shade tree and cocoa pruning on these variables to evaluate the potential impact of this activity.ResultsAgroforestry systems buffered extreme climate events like temperature fluctuations compared to monocultures but reduced light and throughfall drastically. Spatial variability of throughfall and transmitted light were low under a high and closed shade tree canopy. Shade tree pruning resulted in higher canopy openness, light transmittance, and throughfall, while the buffer function of the agroforestry systems concerning temperature and humidity fluctuations was reduced.ConclusionDifferences between cocoa production systems regarding throughfall and microclimate were overlain by pruning activities. Cocoa agroforestry systems are temporal dynamic systems. Pruning timing and intensity is pivotal for balancing light and water availability under seasonally varying environmental conditions to conserve micro-environments for cocoa production with less exposure to unfavorable climate.

Soil moisture has high spatial and temporal variability, depending on topography, soil texture, vegetation and meteorological conditions. It influences many processes in the soil and supplies water to the vegetation. This is often a limiting factor in agricultural production. Over an 18-month period, we measured soil moisture dynamics down to a depth of 70 cm in a long-term trial in Bolivia comprising six different land-use systems, i.e. cocoa monocultures and agroforestry systems, both under organic and conventional management, successional cocoa agroforestry systems and a natural fallow. Soil was heterogeneous over the area and in depth. We identified and separated two soil groups which differed in both, texture and soil water retention capacity. Considering the two groups, we assessed the effect of the different land-use systems on soil moisture dynamics and plant available water on the one hand, and how different soil moisture conditions affect growth and production of cocoa on the other. In monocultures with shallow rooting cocoa only, soil moisture decreased mainly in the uppermost soil layer during the dry season and the lower layers kept more moisture year round. In agroforestry systems soil moisture decreased homogeneously over the soil profile, implying a complementarity in water use of cocoa and deeper rooting trees. The uppermost soil layer in the agroforestry systems had higher soil moisture than in the monoculture, demonstrating the role of shade trees to reduce water loss from top soil by evaporation and transpiration of the cocoa. Even though one soil group had continuously higher water availability than the other group, we did not find an effect on the cocoa yield. Cocoa relies on sufficient water supply, but beside information on the precipitation it is important to know the soil structure and soil water retention capacity when discussing water availability for cocoa production and to consider the heterogeneity of the soil even over small area.

Predicting potential habitats of endemic species is a suitable method for biodiversity conservation and rehabilitation of rangeland ecosystems. The present study was conducted to estimate the geographic distribution of Artemisia sieberi ( A. sieberi ) and Artemisia aucheri ( A. aucheri ), find the most important environmental predictor variables and seek for similarities and differences in habitat preferences between the two species for Poshtkouh rangelands in Central Iran. Maps of environmental variables were created by means of geographic information system (GIS) and geostatistics. Then predictive distribution maps of both species were produced using the maximum entropy modeling technique (Maxent) and presence-only data. Model accuracy is evaluated by using the area under the curve (AUC). Lime1, gravel1, lime 2 and elevation most significantly affect habitat distribution of A. aucheri , while habitat distribution of A. sieberi is affected by elevation, lime1, am1, lime2, and om2. For both species, elevation has an influence on their potential distributions. However, A. aucheri depends more on elevation, and consequently climate in comparison to A. sieberi . Finally, it is revealed that the potential distribution of A. aucheri is limited mostly to mountainous landscapes while A. sieberi is present in wide ranges of environmental conditions.

The global importance of wetlands in the carbon and nitrogen cycles is well documented, but the specific greenhouse gas characteristics of South African wetlands are less well known. These wetlands most likely differ from more prominent wetlands from continuously humid climate zone (boreal, temperate and tropics). Particular wetlands in the southern Drakensberg are adapted to the seasonal drying during the winter months. Greenhouse gas emissions were measured during natural rewetting at two wetlands. A rapid reaction and significant positive correlation between greenhouse gas fluxes and ground water level were determined. Methane emissions were observed after two days of rewetting at one of the wetlands, and nitrous oxide emissions started within a day of rewetting at the other wetland. The high nitrous oxide emissions may be caused by the recent winter burning of vegetation, which most likely resulted in a greater availability of nitrogen in the soil. High nitrous oxide emissions following natural rewett...

The reduction of tropical deforestation is of crucial importance for mitigating climate change and curbing the loss of biodiversity. In light of the current international efforts to reduce deforestation associated to REDD+, effective and efficient country-specific policy options need to be identified to make progress on the ground. Taking lowland Bolivia as an example, we propose a systematic approach to identify and discuss such policy options; this systematic approach can be applied to other tropical contexts with ongoing conversion of forests to agricultural uses. We begin with the distinction of three land use categories associated with the main proximate causes of deforestation in lowland Bolivia, viz. mechanized agriculture, small-scale agriculture and cattle ranching, each of them linked to typical agents. Based on a systematic analysis of spatial and socioeconomic criteria, we then estimate the potential of land use expansion and the likely costs of deforestation reduction in order to formulate suitable policy options for each of the three proximate causes of deforestation. Although mechanized agriculture caused more than half of deforestation in lowland Bolivia, we argue that cattle ranching activities, which contributed to 27% of deforestation between 1992 and 2004, should be targeted as a priority since its expansion threatens forests in many different locations and improvements could be achieved at relatively low costs. In this light, enforcing land use legislation, accompanied by strengthening institutions on national and local levels, constitute tasks of utmost importance.

Forests in lowland Bolivia suffer from severe deforestation caused by different types of agents and land use activities. We identify three major proximate causes of deforestation. The largest share of deforestation is attributable to the expansion of mechanized agriculture, followed by cattle ranching and small-scale agriculture. We utilize a spatially explicit multinomial logit model to analyze the determinants of each of these proximate causes of deforestation between 1992 and 2004. We substantiate the quantitative insights with a qualitative analysis of historical processes that have shaped land use patterns in the Bolivian lowlands to date. Our results suggest that the expansion of mechanized agriculture occurs mainly in response to good access to export markets, fertile soil, and intermediate rainfall conditions. Increases in small-scale agriculture are mainly associated with a humid climate, fertile soil, and proximity to local markets. Forest conversion into pastures for cattle ranching occurs mostly irrespective of environmental determinants and can mainly be explained by access to local markets. Land use restrictions, such as protected areas, seem to prevent the expansion of mechanized agriculture but have little impact on the expansion of small-scale agriculture and cattle ranching. The analysis of future deforestation trends reveals possible hotspots of future expansion for each proximate cause and specifically highlights the possible opening of new frontiers for deforestation due to mechanized agriculture. Whereas the quantitative analysis effectively elucidates the spatial patterns of recent agricultural expansion, the interpretation of long-term historic drivers reveals that the timing and quantity of forest conversion are often triggered by political interventions and historical legacies. peerReviewed

Since the 1980s, mechanized soybean production in Bolivia has caused extensive deforestation in the northeast of Santa Cruz de la Sierra in the eastern Bolivian lowlands. We analyze the spatial and temporal dynamics of deforestation due to mechanized agriculture with spatially explicit logistic regression models. Deforestation patterns are derived from the classification of Landsat imagery by Killeen et al. (2007) and include five time steps (1976, 1986, 1992, 2001 and 2005). We associate deforestation with geophysical and socioeconomic determinants. Our model controls for spatial autocorrelation and temporal dependencies, and we assess the robustness of the results for several model formulations. The expansion of mechanized agriculture is concentrated in areas with favorable environmental conditions, good market access and close proximity to prior deforestation. While overall dynamics remained relatively stable over time, the expansion of mechanized agriculture between 2001 and 2005 became more tolerant to excessive rainfall and less dependent on fertile soils. This mirrors the increasing penetration of mechanized agriculture into humid and less fertile Amazonian rainforests in the northern portion of the study area. The map of deforestation probability substantiates these patterns and shows the highest propensities for future deforestation in the north. Our study demonstrates the value of spatial regression models to better understand the development of deforestation dynamics over a 30-year time span, and contributes to the formulation of policies that aim to reduce deforestation. Yet the results are sensitive to hidden correlations between independent variables, and we therefore advocate a careful evaluation of regression results for different model formulations.

Deforestation and fragmentation are threats to the conservation of species and have consequences for ecosystem functions. The focus of this study was to elucidate forest cover change in the period of 1993 to 2014. Our study area is in the central region of Veracruz, Mexico. Land cover and land use classes for the Years 1993, 2000, and 2014 were derived from Landsat images applying supervised classification. Then, we quantified the net change in forest area, the loss of original forest area, and evaluated forest fragmentation using landscape metrics. Our results showed that the area covered by remnant forests decreased 57%. The annual net forest cover change rate for 1993 to 2000 was −0.44%; since then forest cover increased at a rate of 0.11% from 2000 to 2014. The decreasing total edge density and the mean proximity index during the entire period of the study indicate decreasing irregularity in the shape of remnant forest patches and a slight decrease of vulnerability to edge effects. Forest patches augm...

Ecosystem functions are a central topic of environmental valuation research. Lay respondents are usually unfamiliar with the implications of scientific descriptions of ecosystem functioning. Thus, the applicability of stated preference methods for the valuation of ecosystem functions is a matter of debate. In the general discourse on the economic valuation of ecosystem functions, it was suggested to valuate ecosystem functions via the ecosystem services they provide. In this contribution, we argue that the recognition of this principle is the key also for the applicability of stated preference methods to the valuation of ecosystem functions. Successful application requires a precise differentiation between the descriptive realm of ecosystem functions and the evaluative realm of ecosystem services. On this basis, an ecosystem service approach for the economic valuation of ecosystem functions is introduced. We illustrate the ecosystem service approach by the valuation of a hydrological ecosystem function in rural Indonesia. Identification and representation of the ecosystem services were based on extensive investigations of respondent perception of hydrological phenomena. The availability of irrigation water during the dry season turned out to be a locally decisive ecosystem service. Within the case study, willingness-to-pay (WTP) values were estimated for changes in the availability of irrigation water, rattan, shading in cacao plantations, and in the population of an endemic mammal by Nested Logit (NL) analysis of choice experiment data. Only few respondents lacked sufficient familiarity of the environmental goods to be valued. WTP for a reduction in water scarcity by one month was ~ 39–40,000 Indonesian Rupiah/household/year. A rating of respondent comprehension correlates with preferences for water availability. For respondents with above average comprehension (rated 4 versus mean of 3.12 at a 5-point scale), NL analysis predicts a 14.1% increase in WTP. Interactions of attitudinal constructs support the notion that the WTP estimate is an expression of underlying values and risk perceptions. The ecosystem service approach comes at a cost. Because ecosystem services relevant to local respondents are valued rather than scientifically described ecosystem functions, typical ‘basic science’ models that represent ecosystem functioning cannot be used for the analysis of valuation scenarios with direct policy relevance. Engineering-type models that embody technical and, in our case study, agronomic knowledge are necessary to bridge the gap between ecosystem functioning and their practical implications. A lack of this kind of information also hinders a meaningful application of alternative valuation approaches.

Losses of biodiversity and ecosystem functioning due to rainforest destruction and agricultural intensification are prime concerns for science and society alike. Potentially, ecosystems show nonlinear responses to land-use intensification that would open management options with limited ecological losses but satisfying economic gains. However, multidisciplinary studies to quantify ecological losses and socioeconomic tradeoffs under different management options are rare. Here, we evaluate opposing land use strategies in cacao agroforestry in Sulawesi, Indonesia, by using data on species richness of nine plant and animal taxa, six related ecosystem functions, and on socioeconomic drivers of agroforestry expansion. Expansion of cacao cultivation by 230% in the last two decades was triggered not only by economic market mechanisms, but also by rarely considered cultural factors. Transformation from near-primary forest to agroforestry had little effect on overall species richness, but reduced plant biomass and carbon storage by approximately 75% and species richness of forest-using species by approximately 60%. In contrast, increased land use intensity in cacao agroforestry, coupled with a reduction in shade tree cover from 80% to 40%, caused only minor quantitative changes in biodiversity and maintained high levels of ecosystem functioning while doubling farmers' net income. However, unshaded systems further increased income by approximately 40%, implying that current economic incentives and cultural preferences for new intensification practices put shaded systems at risk. We conclude that low-shade agroforestry provides the best available compromise between economic forces and ecological needs. Certification schemes for shade-grown crops may provide a market-based mechanism to slow down current intensification trends.

Knowledge about soil formation in tropical montane rainforests is scarce and patchy. We examined the altitudinal change of soils in a Bolivian tropical montane rainforest, aiming to illuminate the contribution of podzolization and hydromorphic processes to soil formation. In three transects from 1700 m to 3400 m a.s.l. we determined the pH, exchangeable cation exchange capacity, carbon and nitrogen stocks, and iron and aluminium fractions from 26 soil profiles. Three zones of different dominant soil forming processes were found: In the lower montane forest (LMF, 1700–2200 m a.s.l.), Dystropepts with high nutrient concentration and acidity were common. The pronounced change to the upper montane cloud forest (UMCF, 2200–2700 m a.s.l.) coincided with the appearance of Placorthods with more acidic conditions, deep ectorganic horizons and increasing translocation of sesquioxides. In the sub-alpine forest (SCF, 2700 m–3400 m a.s.l.), hydromorphic processes dominated over podzolization, resulting in Placaquods with low mineralization rate and nutrient concentration. This shows that due to increasing wetness and colder temperatures at high altitudes, dominant soil forming processes change from podzolization to hydromorphism soils with increasing altitude.

The restoration of drained peat bogs in Northwest (NW) Europe is an important task of soil protection, but needs to cope with warmer and drier summers. Our examination took place in the Pietzmoor bog (Schneverdingen, NW Germany) that had been drained for fuel peat extraction until the 1970s and rewetted since then. We determined carbon dioxide (CO 2 ) efflux in situ and in laboratory incubations. Also, we analyzed pore water for dissolved organic carbon (DOC), total and dissolved organic N (DON), nitrate (NO 3 – ) and ammonium (NH 4 + ) concentration. In Schneverdingen, the summer 2003 was record-breaking hot (mean temperature June to August elevated > 3 K compared to long-term average) and dry (precipitation during the same period 42 cm below the surface in July 2003, when in situ soil CO 2 efflux was up to 23.4 g m –2 d –1 compared to 15.7 g m –2 d –1 in September. Prior to March 2003, DOC concentrations in pore water were –1 and NH 4 + was the dominant fraction of mineral N. In July 2003, DOC concentration rose to 249 g l –1 , DON concentrations more than doubled, and NO 3 – became the dominant fraction of mineral N. Due to the increased future likelihood of hot and dry summers in NW Germany, peat bog restoration efforts need take care that a water table close to the surface is maintained.

Universitatsdrucke Gottingen Universitatsdrucke Gottingen The Carbiocial Project investigates viable carbon-optimized land management strategies for maintaining tropical ecosystem services under land use change and changing climate conditions in Southern Amazonia – a hotspot of global change. The project aims at understanding the vital natural processes and socio-economic driving forces in the region and develops strategies to enhance and protect carbon stocks in the recently deforested agroscapes of Central/Northern Mato Grosso and South Para. That is why Carbiocial analyzes and models soil, water and climate as well as agro-economics, social and political transformations. Based on detailed storylines, the project aims at identifying possible entry-points for a necessary change in local and regional production patterns, considering local livelihoods as well as the present national and global economic, legal and political situation. This book gives an overview of the fi rst results of the multi-disciplinary Carbiocial Project by publishing the main presentations, held on the Carbiocial Status Conference, on October 7-8, 2013, in Cuiaba. In sixteen chapters the authors elucidate the project‘s current state of knowledge, illustrating adapted methods for regional modeling and promising strategies for the Amazon development.

In the light of global change, the necessity to monitor atmospheric depositions that have relevant effects on ecosystems is ever increasing particularly for tropical sites. For this study, atmospheric ionic depositions were measured on tropical Central Sulawesi at remote sites with both a conventional bulk water collector system (BWS collector) and with a passive ion exchange resin collector system (IER collector). The principle of IER collector to fix all ionic depositions, i.e. anions and cations, has certain advantages referring to (1) post-deposition transformation processes, (2) low ionic concentrations and (3) low rainfall and associated particulate inputs, e.g. dust or sand. The ionic concentrations to be measured for BWS collectors may easily fall below detection limits under low deposition conditions which are common for tropical sites of low land use intensity. Additionally, BWS collections are not as independent from the amount of rain fallen as are IER collections. For this study, the significant differences between both collectors found for nearly all measured elements were partly correlated to the rainfall pattern, i.e. for calcium, magnesium, potassium and sodium. However, the significant differences were, in most cases, not highly relevant. More relevant differences between the systems were found for aluminium and nitrate (434–484 %). Almost five times higher values for nitrate clarified the advantage of the IER system particularly for low deposition rate which is one particularity of atmospheric ionic deposition in tropical sites of extensive land use. The monthly resolution of the IER data offers new insights into the temporal distribution of annual ionic depositions. Here, it did not follow the tropical rain pattern of a drier season within generally wet conditions. peerReviewed

Tropical montane cloud forests (TMCFs) are differentiated from other forest types by their frequent immersion in fog. This characteristic implies that TMCFs are unique in their hydrological functioning, as they receive a substantial amount of water input via direct deposition of cloud droplets. Because it is generally associated with reduced solar radiation and increased humidity, frequent fog occurrence can lower evapotranspiration (ET). Many TMCFs also have certain characteristic structural and floristic features, which have further hydrological effects. Cloud water is often chemically different from rain water (Heath 2001; Liang et al. 2009); hence, fog deposition can alter inputs of nutrients and other chemicals into the ecosystem. The hydrological, biological, and chemical characteristics of cloud forests give rise to differences in biogeochemical processes as well.

Forest conversion and natural interannual climate fluctuation as ENSO-events are key determinants of water balances in tropical catchments. Distributed hydrological modelling that relates land cover changes and climate changes with river discharge are rare for humid tropical catchments at the mesoscale. In the present paper we present a hydrological modelling approach to describe the impact of land cover changes and ENSO-events on the water resources in a mesoscale humid tropical catchment. These are based on hydro-meteorological measurements that were performed in the Gumbasa catchment from 2002 to 2005 in the frame of STORMA.

This study investigates throughfall rates and nutrient fluxes in two cacao plots and one natural forest plot in Central Sulawesi, Indonesia. Throughfall was collected over a 12 month period on each plot with bulk precipitation samplers and compared with open area precipitation of nearby reference sites. Samples of both throughfall and gross precipitation were analysed for chemical composition and nutrient enrichment.

Indonesia’s annual deforestation rate of –1.2% is dramatic compared for example to Brazil’s 0.4% loss of forest cover. Sulawesi region of Indonesia still has a forest cover of 48%, but as population has been growing by 66% over the past 2 decades, massive land cover transformations are going on that have changed the land cover pattern and consequently soil and water resources of the region are altering as well. Since 2001, we investigate the impact of forest conversion on the water balance, nutrient losses and soil erosion of a small mesoscalic tropical catchment, which is integrated into the long-term interdisciplinary collaborative project STORMA (http://www.storma.de). The study was conducted in a small mountainous catchment, which is located at the north-eastern border of the Lore Lindu National Park Central of Sulawesi. The Nopu catchment (51S 01757231E, 9867683 N) covers an area of approximately 2.6 km2. Since 2001 the catchment is monitored with three weirs (automatic stage recorder), one climate station and six rain gauges. Traditional slash & burn cultivation is predominant and heavy machinery is not used. At two sub-catchments (rainforest weir 3, slash & burn weir 2) changes in river discharge and nutrient outputs with time and differences were analysed since 2002. As indicators for land degradation we studied the changes of infiltration rate, water flow path (increasing interflow and surface flow) and soil nutrient output with river discharge. In the Nopu catchment slash & burn activities increased mainly since 2003/2004 with forest reduction until 2007 in the sub-catchment weir 2 from 87% (2001) to 26% forest cover (2007). Due to forest conversion, river discharge increased from 9 to 17% for the period 2002/2003–2005/2006 mainly driven by increase in overland flow and quick interflow. Three scenarios (forest/cacao/slash & burn (corn with cassava)) were simulated with the application of the water balance model WASIM-ETH. Simulation results supported the experimental results showing an increase from 8% to 17% annual discharge for cacao and slash & burn scenario and give insight into the changing discharge components. The increase in overland flow leads to an increase in soil erosion with doubling of suspended sediment output from 2003 to 2005. Also, higher soil nutrient leaching and increase in quick interflow has caused an increase by ratios of 1.5–1.9 of the main cations (Ca, Mg, K) and nitrogen (TNb) in the sub-catchment partially deforested compared to the natural forest sub-catchment. After 2005/2006, land degradation indicators of suspended sediment output and soluted nutrient output indicate a “stabilizing effect” with decrease due to land use change to cacao agroforestry in the mid slopes of the catchment.

In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m−2 h−1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m−2 h−1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain nitrous oxide release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

Precipitation anomalies caused by the warm phase (El Niño) of the ENSO cycle lead to a strong decrease of water resources in South-East Asia. The aim of this work is to study the impact of warm phase ENSO caused precipitation anomalies on the water balance of a mesoscale tropical catchment in Central Sulawesi, Indonesia using a scenario analysis. We applied statistically generated precipitation anomalies caused by warm phase ENSO events on a validated hydrological model of the Palu River catchment (2694 km2) to investigate the implications of the generated ENSO scenarios on the total annual water balance, the annual discharge regime and the discharge variability. Moreover we analysed the influence of various catchment characteristics during warm phase ENSO conditions on the discharge variability through a comparison of different sub-catchment types. The results of the scenario analysis proved a severe decline of the annual discharge rate during warm phase ENSO conditions and an increase of the overall discharge variability.

Apart from the forest floor, the canopy of forested ecosystems functions as the second most important source for dissolved and particulate fractions of organic and inorganic C and N compounds. However, under mass outbreak situations of insect herbivores this flux path of organic matter is considerably intensified clearly exceeding C and N fluxes from the forest floor. In this paper we report on herbivore-altered C and N fluxes from the canopy to the forest floor and effects on forest floor nutrient fluxes during severe defoliating herbivory of the winter moth (Operophtera brumata) and the mottled umber moth (Eranis defoliaria) in an oak forest in Germany. Over the course of 6.5 months we followed the C and N fluxes with bulk deposition, throughfall solution, insect frass deposits (green-fall together with insect faeces) and with forest floor solution in an 117-yr-old oak (Quercus petraea) forest. Compared to the control, herbivore defoliation significantly enhanced throughfall inputs of total and dissolved organic carbon and nitrogen by a factor of 3 and 2.5 (for TOC and DOC), and by 1.4 and 1.3 times (for TNb and DNb), respectively. Frass plus green-fall C and N fluxes peaked in May with 592 kg C ha−1 and 33.5 kg N ha−1 representing 79.6% (for C) and 78.3% (for N) of the total C and N input over 2.5 months. The quantitative and qualitative C and N input via faeces and litter deposition significantly differ between the insect affected and non-affected site. However, the C and N fluxes with throughfall did not significantly correlate with forest floor leachates. In this context, forest floor fluxes of TOC, DOC and NO3-N were significantly lower at the infested site compared to the control, whereas fluxes of NH4-N together with DON were significantly higher. The study demonstrates the importance of linking the population and associated frass dynamics of herbivorous insects with the cycling of nutrients and organic matter in forest ecosystems, highlighting the remarkable alterations in the timing, amounts and nature of organic matter dynamics on the ecosystem level. Consequently, the ecology of phytophagous insects allows partly to explain temporal-spatial alterations in nutrient cycling and thus ecosystem functioning. peerReviewed