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• A strategic risk-screening approach to water quality has been applied in Scotland. • Screening identified dominant risk factors and higher-risk catchments. • Risks were highlighted for colour and linked to management of organic soils. • Bacteriological quality parameters were linked to agricultural land uses. • Risks are likely to be further modified by land use changes and climate change. Water resources provide multiple services, one of the most important the provision of drinking water, conventionally treated before public consumption as potable supplies. With increasing pressures from land use and climate change, there are advantages to be gained from considering raw water quality as a fundamental characteristic of the natural resource, and to anticipate emerging risks within the catchments rather than relying on treatment. This research proposes a large-scale, rapid risk screening of raw water quality based on catchment sensitivity to pressures as prerequisite to a more strategic inclusion of emerging risks in water resource and ecosystem management. Raw water quality observations from 154 surface water catchments in Scotland were investigated to determine the national baseline and to identify current pressures and underlying drivers. Patterns and spatial dependencies were investigated using principal component analysis, redundancy analysis, cluster analysis, and regression trees. These statistical approaches highlight the interaction between intrinsic catchment biophysical properties, land use and climate in characterising water quality risks and identify the focus for prioritising catchment interventions and risk-mitigation in the future. The emphasis on raw water quality will also support an ecosystem-based approach to increase catchment resilience, to ensure long-term supply of good quality drinking water while simultaneously creating wider benefits for society and the environment. [ABSTRACT FROM AUTHOR]

• Multiple buffer zone and catchment management options exist to conserve the study freshwater ecosystem. • The co-developed and designed management options support to address the complex challenges. • Co-developing management options should take short-term economic benefits and long-term environmental goals into account. • Putting adaptive learning in place support to adapt the management options with the changing socio-ecological context. • Capacitating local level practitioners through on job trainings and knowledge co-production is crucial. Freshwater ecosystems are important for directly ensuring a range of benefits and services that sustain local livelihoods and help mitigate climate change. However, freshwater ecosystems are threatened by anthropogenic and natural pressures affecting their ability to sustainably provide these services. Managing freshwater ecosystems is mainly challenged by the complexity of the drivers of their degradation and by the difficulty of balancing the need for short-term socioeconomic development and protecting and restoring ecosystems to support long-term, sustainable development. Addressing such challenges requires an integrated and systematic approach, catchment-wide management and meaningful engagement and collaboration among stakeholders. The present study was conducted in Lake Ziway, Rift Valley Lakes Basin, Ethiopia. The overarching objective was to conserve the freshwater ecosystem through co-planning and designing management options for the buffer zone and entire catchment. The study engaged local communities through multiple approaches including inception and validation workshops, reconnaissance surveys, key informant interviews and focus group discussions. It also employed quantitative data collection methods to characterize the freshwater ecosystem and entire catchment. The participatory approach employed in this study identified multiple management options including tree-based forest and landscape restoration measures, integrated soil and water conservation, and multiple buffer zone restoration measures. The identified and validated management options are aimed at improving the functionality of the freshwater ecosystem in the face of increased need of economic development and climate change. Furthermore, the study provided key recommendations to support the processes of policy development and the effective implementation of suggested and validated management options. [ABSTRACT FROM AUTHOR]

Highlights • Integrated valuation is used to explore win-win scenarios of catchment land use change to improve downstream water quality. • By considering ecosystem services values, we show that land use change can lead to lake water quality improvements and economic benefits. • Management can encourage land use change through incentives such as Payment for Ecosystem Services and innovative land use funds. Abstract A significant challenge in resource management is addressed: the perceived trade-off between economic growth and ecosystem restoration and conservation. Traditional approaches to management regard restoration as a potential cost to economic productivity. In this study we show that by considering a broader range of economic values, including ecosystem services values, an argument can be made that restoration of lake ecosystems also leads to favourable economic outcomes when commonly disregarded values are considered. Our case study analyses the ecological outcomes of different catchment mitigation and land use scenarios in terms of water quality results in a lake, assessing changes in land use values based on opportunity costs, and ecosystem services values. We show that when considering the value of ecosystem services, intensive agricultural land use is not necessarily the most economically valuable form of land use within a lake catchment. Indeed, a shift towards alternative land uses within a catchment can lead to both ongoing economic benefits and improvements in water quality. In this context, land-use change offers an option for water quality improvement that minimises lake and land mitigation costs, while adding value to catchment land use. An argument is made supporting land use change towards indigenous forest types, which can sustain alternative sources of income such as a range of recreational values, while supporting important ecosystem functions for the region. [ABSTRACT FROM AUTHOR]

• In highly degraded watersheds, cropland loss reduces ecosystem service values even as plantations increase. • The economic incentives of plantations aggravated the loss of cropland in the two highly degraded watersheds. • Many households could be vulnerable to external shocks due to reduced ecosystem service values. • Understanding the role of individual and community behavior in the observed changes is crucial. • Conserving croplands through upstream and downstream area restoration could reduce ecosystem service loss. Ecosystems provide a variety of ecosystem services and functions for mankind, and their sustainable use plays an important role in livelihoods. However, the resulting land degradation due to land use and land cover changes leads to loss of valuable ecosystems and associated ecosystem functions and services. This study takes two highly degraded watersheds, Aba-Bora and Guder, in Ethiopia and uses the value transfer valuation method to estimate changes in ecosystem service values. The study shows how loss of cropland and grazing lands can significantly affect ecosystem services even when plantations and shrubland increase. The results suggest that over a period of 41 years, the ecosystem service value of exclosures/shrublands and plantations increased, whereas that of crop and grazing lands decreased. The loss of ecosystem service values due to the decrease in cropland and grazing lands outweigh the gains due to the expansion of plantations and exclosures and resulted in a total loss of ecosystem service values of US$ 1.6 million in Aba-Bora watershed and US$ 24.4 million in Guder. In both watersheds, the greatest contributor to ecosystem service loss was a decline in supporting services, while the increase in plantation and shrublands (mainly through establishment of exclosures) meant that regulating ecosystem services suffered the smallest loss. Given their importance to livelihoods in these areas, the loss in crop and grazing lands significantly increase the vulnerability to shocks and narrow future livelihood options for many households. Given that severe gully erosion is the major contributor to the reduction in crop and grazing lands, catchment management that integrates the conservation of upstream areas using diverse sustainable land management practices, and gully rehabilitation measures in downstream areas could be an important option to reducing the expansion of big gullies, and conserving crop and grazing lands and ecosystem service values. However, the results suggest that the risks to livelihoods may be underestimated while the effectiveness of current actions to address land degradation over-estimated by communities. [ABSTRACT FROM AUTHOR]

Deterministic distributed model has been confirmed as one of highest performance model for representing the hydrological regime. By the capacity of covering all hydrological components in a catchment, this model is expected to be an effective tool for restoring the stream flow data, especially at lack of data catchment. In this study, a deterministic hydrological model - MIKE SHE (DHI) - is applied for reproducing the daily flow data in 20 years of Cu De river catchment, Viet Nam. The model is constructed over 425.2 Km2 with most of catchment's hydrological components. These components are set up in principle based on the characteristics of neighbouring catchment, Vu Gia - Thu Bon. [ABSTRACT FROM AUTHOR]

The inclusion of an ecosystem services framework into planning and decision-making processes is increasingly being seen as a means to further a better implementation of the Ecosystem Approach and to achieve a more sustainable allocation of resources. Tools are slowly emerging to help scientists and practitioners with mapping ecosystem services. This study reviewed three tools with regard to their potential use as standard tools to be employed in local planning. To this end, an email survey was conducted first to identify the most important criteria practitioners require in an ecosystem services mapping tool. InVEST and EcoServ-GIS were then applied to produce several ecosystem services maps for a small catchment in the Scottish Borders. These maps were compared to already existing maps produced with another method, SENCE. We showed that there can be substantial variations in maps produced with different tools. These reflect the differences between the tools, especially in their requirements for data, their user friendliness and their accuracy. Our comparison highlights that tools so far have had to make a compromise between usability and scientific accuracy, which means that practitioners need to carefully weigh the requirements for a specific project before deciding on the appropriate tool. [ABSTRACT FROM AUTHOR]

The promise of integrated research for addressing complex problems of sustainability such as catchment management has been widely recognised. However, the mechanisms for achieving integration in research have been the subject of few empirical studies. A major challenge of doing integrated research is how to combine and effectively manage diverse disciplinary perspectives and other knowledge/s in the generation of new knowledge for practice and policy change. We examined this challenge within a large catchment management research project in Australia's Murray Darling Basin and asked, ‘What supports or enables integration in research?’ Addressing this question requires an attention to integration as a dynamic process of knowledge production. We propose a model of this dynamic process which is characterised by a changing demand for integration in five different phases: (1) establishing the imperative for integration; (2) coordinating different disciplinary and other knowledge commitments; (3) consolidating arrangements for integration; (4) prioritising outputs from integration; and, (5) representing outputs of integration. For researchers and research managers this model can help identify the mechanisms required to support effective integration within research projects. We identify these mechanisms as sites and devices for integration that must be both planned (as part of the original integrated research design) and emergent (iteratively created and supported) in research projects. [ABSTRACT FROM AUTHOR]

Highlights: [•] Water supply planning is informed the convergence of social, political, climatic and environmental factors. [•] Urban land use and metropolitan water planning should be concurrent and coordinated activities. [•] Changes in government structure and policy direction may not lead to improvements in water planning and delivery. [•] Drought and disease are catalysts for change in the water sector but momentum of reform must continue beyond the immediate crisis. [Copyright &y& Elsevier]

Abstract: Several attempts have been made to explain the formation of collaborative watershed partnerships—that is, multi-actor groups which work together to resolve environmental problems at a watershed scale. But to what extent do these explanations ‘travel’ from their original home – namely the USA – to other jurisdictions, where similar claims are being made about the rise of collaborative environmental governance? To that end, this article critically evaluates how well one leading theory, namely the political contracting framework (PCF), explains their emergence in the rather different institutional context of the United Kingdom. Drawing on a survey of collaborative watershed practices, it argues that they are functionally equivalent to partnerships. Furthermore, when suitably amended, the PCF explains many important aspects of their emergence. The same critical factors are associated with their development, but these should now be assessed across the entire ‘life-cycle’ of partnerships. The implications of these findings are identified and explored, the underlying aim being to inform a much more comparative theoretical approach to understanding what appear to be important changes in collaborative environmental governance practices. [Copyright &y& Elsevier]

Abstract: Agricultural diffuse pollution is a significant contributor to water and air quality in many catchments and the need to control harmful emissions remains paramount for government policy. In England, the Demonstration Test Catchments (DTCs) have been established to provide a basis for testing on-farm mitigation measures using collaborative multi-partner research and some of this work is targeting the Hampshire Avon (∼1700km2) catchment. To help provide integrated farm advice across England and Wales, a new Excel-based tool, FARM Scale Optimisation of Pollutant Emission Reductions (FARMSCOPER), has recently been developed for characterising diffuse agricultural pollutant emissions from representative farm types and quantifying the expected impacts of control options on those losses to the environment. Against this background, this paper describes the application of FARMSCOPER in the Hampshire Avon DTC in order to assess its utility at catchment scale and the potential benefits of relevant and practical mitigation options. Spatial datasets and the Agricultural Census returns for 2009 specific to the River Avon catchment were integrated to produce a collection of representative farm types which capture the characteristics of the local physical environment, land use patterns and farm management practices. FARMSCOPER was used to estimate the annual emissions of nitrate, phosphorus, sediment, nitrous oxide, methane and ammonia for each representative farm type. The scenarios investigated comprised baseline losses with no mitigation measures implemented, current emissions using information on the present implementation of options under existing schemes and initiatives and, the maximum potential reduction possible on the basis of implementing all available and relevant options. Model outputs suggested that reductions in pollutant loads in response to the existing uptake of mitigation methods are small (e.g. 10% for phosphorus, 7% for sediment, 4% for nitrate and 5% for nitrous oxide). FARMSCOPER suggested that technically feasible pollutant reductions on the basis of the implementation of more mitigation options could be of the order of 47% for phosphorus, 66% for sediment, 22% for nitrate and 16% for nitrous oxide. This work represents the first catchment scale application of the FARMSCOPER tool. [Copyright &y& Elsevier]

Abstract: Diffuse pollution, and the contribution from agriculture in particular, has become increasingly important as pollution from point sources has been addressed by wastewater treatment. Land management approaches, such as construction of field wetlands, provide one group of mitigation options available to farmers. Although field wetlands are widely used for diffuse pollution control in temperate environments worldwide, there is a shortage of evidence for the effectiveness and viability of these mitigation options in the UK. The Mitigation Options for Phosphorus and Sediment Project aims to make recommendations regarding the design and effectiveness of field wetlands for diffuse pollution control in UK landscapes. Ten wetlands have been built on four farms in Cumbria and Leicestershire. This paper focuses on sediment retention within the wetlands, estimated from annual sediment surveys in the first two years, and discusses establishment costs. It is clear that the wetlands are effective in trapping a substantial amount of sediment. Estimates of annual sediment retention suggest higher trapping rates at sandy sites (0.5–6tha−1 yr−1), compared to silty sites (0.02–0.4tha−1 yr−1) and clay sites (0.01–0.07tha−1 yr−1). Establishment costs for the wetlands ranged from £280 to £3100 and depended more on site specific factors, such as fencing and gateways on livestock farms, rather than on wetland size or design. Wetlands with lower trapping rates would also have lower maintenance costs, as dredging would be required less frequently. The results indicate that field wetlands show promise for inclusion in agri-environment schemes, particularly if capital payments can be provided for establishment, to encourage uptake of these multi-functional features. [Copyright &y& Elsevier]

Abstract: A strategy for use of vegetation to control soil erosion has been developed that is spatially targeted at hotspots and flow pathways in the landscape. It is based on the premise that most of the soil erosion in semi-arid areas is by water erosion along specific flow lines. Soil is removed from fields and transported downslope and into channels if the connectivity of flow and sediment pathways is high, causing offsite problems as well as loss of agricultural productivity. Vegetation can reduce that connectivity by decreasing erosion and increasing sedimentation. The research combines mapping and analysis of the connectivity pathways and erosion hotspots with analysis of the most effective indigenous plants to control erosion and suited to the particular landscape position and environment. The crucial innovative element is the combination of physical process understanding with plant ecology, and its spatial application. The scheme has been developed by research in the driest part of the European Mediterranean region, in SE Spain, and examples of application strategies are illustrated. It is particularly suited to upland rain-fed agricultural areas on soft rocks, which are highly vulnerable to land degradation. Recommendations are provided on locations for planting or encouraging vegetation growth and on suitable species. The spatially targeted strategies apply vegetation to the critical locations to intervene in the pathways and this minimal intervention approach still allows cultivation of fields. The methods proposed can form the basis for sustainable catchment management to combat soil erosion and desertification. [Copyright &y& Elsevier]

Abstract: The Great Barrier Reef (GBR) is a World Heritage Area and contains extensive areas of coral reef, seagrass meadows and fisheries resources. From adjacent catchments, numerous rivers discharge pollutants from agricultural, urban, mining and industrial activity. Pollutant sources have been identified and include suspended sediment from erosion in cattle grazing areas; nitrate from fertiliser application on crop lands; and herbicides from various land uses. The fate and effects of these pollutants in the receiving marine environment are relatively well understood. The Australian and Queensland Governments responded to the concerns of pollution of the GBR from catchment runoff with a plan to address this issue in 2003 (Reef Plan; updated 2009), incentive-based voluntary management initiatives in 2007 (Reef Rescue) and a State regulatory approach in 2009, the Reef Protection Package. This paper reviews new research relevant to the catchment to GBR continuum and evaluates the appropriateness of current management responses. [Copyright &y& Elsevier]

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Abstract: This paper investigates the implementation of governance for sustainable landscapes, based on a catchment case study in lowland England. A participatory research process, spanning six and a half years, employed formal and informal in-depth interviews, focus group work and workshop techniques with 71 stakeholders representative of a wide range of interests in the catchment. A scenario design process within a GIS framework was used as a focus for capturing the key issues and visions of the stakeholders. Two contrasting but plausible scenarios for 2020 emerged from this process; one scenario was driven by the sustainable intensification of agricultural production and world trade, the other by the enhanced protection of ecosystem services and multi-objective land use. It was clear from discussions with stakeholders that the mechanisms for delivering an integrated approach to landscape management are not currently in place, although there have been some policy successes that could be built upon. There is also a need for new approaches to land tenure which include tax incentives and improved forms of cooperation and leadership in both policy and contiguous landscape stewardship. The methodology itself was appreciated by the stakeholders who found it useful to think more holistically. In addition, the study demonstrates an approach that individual practitioners and researchers can develop the skills to implement. [Copyright &y& Elsevier]

Abstract: Lake Chilwa is shared by Malawi and Mozambique, it supports an important fishery and its watershed is undergoing rapid population growth and increasing utilization for agricultural production. It is a shallow, closed basin lake with extensive surrounding wetlands; and it has suffered several desiccation events in the last century. To better understand the current condition of the lake, we monitored a suite of physical, chemical and biological parameters at approximately monthly intervals over an annual cycle in 2004–2005. The limnology of the lake was extremely sensitive to seasonal changes in the lake''s seasonal hydrological cycle. The physico-chemical parameters, temperature, electrical conductivity, and total suspended solids exhibited clear seasonal patterns driven by the highly seasonal rainfall and resultant lake levels. In response, phytoplankton and zooplankton abundance, as well as biologically dependent oxygen concentrations and pH, exhibited several maxima levels over the year. The peaks of phytoplankton and zooplankton were out of phase suggesting a lag in the zooplankton grazing in response to pulses in primary productivity. Chlorophyll concentrations can exceed 1mg/L in surface waters indicative of hypereutrophic conditions, but they fell dramatically during zooplankton peaks. This hydrologically driven, shallow and mesohaline lake is a productive and critical resource to the region. Its management poses challenges arising from the dependence of its limnology and fishery on the lakes hydrology, catchment land use and climate variability. [Copyright &y& Elsevier]

Abstract: The Salinity Investment Framework (SIF3) is designed to help environmental managers make better policy decisions about protecting key assets under threat of dryland salinity, a major degradation problem in Australia. This study reports results from applying SIF3 in partnership with two regional organizations (in the states of Victoria and Western Australia) with contrasting institutional powers and structures. We also engaged relevant policy makers with a view to influencing national policy. Available knowledge, science, and data were used to develop region-specific recommendations for public investment in salinity management. SIF3 proved easy to apply, requiring minimal changes from its original version. Establishing trust and credibility with stakeholders was extremely important. More time was required to be spent on communicating what SIF3 was and what it would mean for stakeholders than in applying it in the catchments. In both regions, recommendations included making a clear distinction between localized assets (such as a particular wetland) and dispersed assets (such as agricultural land as a whole); more targeted investment in spatially identified localized assets; using a broader range of policy tools; basing recommendations on the levels of public and private net benefits; anticipating the adoptability of sustainable land-management practices; and formally integrating relevant scientific, economic and social information with community values. The differences between current action and recommendations were significant in both regions, particularly in Victoria. As a result of our work both regions have decided to implementing a similar asset-based approach covering various environmental threats in addition to dryland salinity. The research indicates that it is feasible to use decision frameworks such as SIF3 to improve the rigour of decision making by community-based environmental management organizations. A broader range of policy tools are needed for dryland salinity, with less reliance on extension and small grants, and more emphasis on intervention around key assets and investment in technology development. We have influenced policy makers to some extent at state level and nationally through discussion of SIF3 in a national inquiry, preparation of a policy paper for peak multi-government policy committees, briefings and provision of advice on policy design. Despite this, achieving significant policy change at the state and national levels remains difficult for a number of reasons. Governments give limited signals to environmental managers to achieve environmental outcomes, being more concerned with community participation objectives and political considerations. We hope for significant policy change with increased scrutiny about sound decision making and public accountability. [Copyright &y& Elsevier]

Integrated watershed management (IWSM) was implemented to address issues of poverty and land resource degradation in the 14,500ha upper Agula watershed, in semi-arid Eastern Tigray (Ethiopia), an area known for poverty and resource degradation caused by natural and man-made calamities. The purpose of this study was to assess the impact of IWSM and determine the land use and cover dynamics that it has induced. The change in land use and cover was assessed by integrating remote sensing and geographic information systems (GIS). Two sets of aerial photographs (taken in 1965 and 1994 at scale of 1:50,000) and Landsat ETM+ image (taken in 2000 with 30m resolution) were used to produce the land use/land cover map and assess land use change. The results reveal significant modification and conversion of land use and cover of the watershed over the last four decades (1965–2005). A significant portion of the watershed was continuously under intensively cultivated (rainfed) land. The area under irrigation increased from 7ha to 222.4ha post-intervention. The area under dense forest increased from 32.4ha to 98ha. The study further shows that IWSM decreased soil erosion, increased soil moisture, reduced sedimentation and run off, set the scene for a number of positive knock-on effects such as stabilization of gullies and river banks, rehabilitation of degraded lands. IWSM also resulted in increased recharge in the subsurface water. This study reconfirms the importance of IWSM as a key to improve the land cover of watersheds, as a contribution to poverty alleviation and sustainable livelihood. [Copyright &y& Elsevier]

Abstract: There is increasing recognition that fine sediment represents an important diffuse source pollutant in surface waters, due to its role in governing the transfer and fate of many substances, including nutrients, heavy metals, pesticides and other organic contaminants, and because of its impacts on aquatic ecology. Catchment management strategies therefore frequently need to include provision for the control of sediment mobilisation and delivery. The sediment budget concept provides a valuable framework for assisting the management and control of diffuse source sediment pollution and associated problems, by identifying the key sources and demonstrating the importance of intermediate stores and the likely impact of upstream mitigation strategies on downstream suspended sediment and sediment-associated contaminant fluxes. Accordingly, the utility of the sediment budget concept for catchment management is further discussed, by introducing examples from several contrasting river basins. [Copyright &y& Elsevier]

In response to the challenges of sustainable development, this paper describes the formulation and application of a framework of catchment-level water resource use and management indicators designed to integrate environmental, economic, and social aspects of sustainability. The framework of nine indicators was applied to the River Clyde catchment in Scotland, using existing secondary data and in a manner that recognized local thresholds and standards, where appropriate. Findings suggested a mixed and relatively complex situation, with encouraging results for water quality and supply, but much room for improvement regarding the preparedness of management systems and opportunities for public participation. The availability of adequate data in a suitable, catchment-Ievel format was a significant problem, although this situation may improve with the advent of new legislation. Discussion of findings also addresses the inherently subjective nature of indicator selection and the opportunities provided by research in this area for greater cooperation and collaboration between natural and social scientists. [ABSTRACT FROM AUTHOR]

Abstract: Climate change is predicted to increase fire frequency and exacerbate water scarcity. The effect of these changes on the tree harvest decision in a forested catchment is investigated using stochastic dynamic programming, taking a stand of mountain ash (Eucalyptus regnans) in south–eastern Australia as a case study. We find that for a range of water and carbon sequestration values, it is optimal to cease harvesting in the absence of climate change. Whether it is optimal to do so under climate change will depend on the magnitude of the increases in fire frequency and water value. Potential increases in forest productivity also have a significant impact on the tree harvest decision. [Copyright &y& Elsevier]

This paper describes the evolution of soil erosion perception with policy makers and farmers in Flanders, and how these changes have resulted in the emergence of a soil conservation policy. Until the mid 1990s, soil erosion and its related problems received little attention in the environmental debate. This has changed through increased interest in environmental issues in general, as well as an increasing number of scientific reports on soil erosion and sediment delivery. New legislation that made the sediment problem a big financial issue in 1995, however, was the main reason for the recognition of soil erosion as an environmental problem with the policy makers. Despite the lack of monitoring soil erosion, a soil conservation policy emerged recently, which is clearly represented in the 2001 “soil erosion decree” by the Flemish government. This policy provides important opportunities for soil conservation as it incorporates both scientists and farmers. The involvement of farmers in demonstration projects is crucial with this respect as they have to be convinced about the usefulness and applicability of soil conservation measures. Farmers also participate in the development of a management plan. However, the success of the new policy could be undermined by its rapid development. There is still a lack of data underpinning the status of the erosion problem, and, the goals of the policy are not clearly defined. Furthermore, the administrative organisation is currently not favourable for an optimal co-operation with the farmers. [Copyright &y& Elsevier]

Invasive alien plants are consumptive water-users, and may have reduced river flows in South Africa by about 6.7% according to a broad-scale study. An effective programme to bring the invasions under control would cost about US$ 92 million per year for the next 20 years. This paper reports on studies of four representative catchments (the Sonderend, Keurbooms, Upper Wilge and Sabie-Sand) to assess the impacts and costs of invasions at a scale that is more relevant to managers. Several alien plant species have invaded the catchments. Non-riverine invasions are mainly Pinus and Hakea species in Sonderend and Keurbooms, eucalypts in the Upper Wilge, and pines and scramblers (e.g. Lantana camara) in the Sabie-Sand catchment. Riverine invasions are dominated by Acacia mearnsii and, to a lesser extent, A. dealbata, except in the Sabie-Sand and the lower Sonderend River where Eucalyptus species are important. About 44% of the Sonderend, 54% of the Keurbooms, 2% of the Upper Wilge and 23% of the Sabie-Sand catchments has been invaded to some degree. The corresponding reductions in the natural river flows attributed to these invasions are about 7.2, 22.1, 6.0 and 9.4%. If the invasions are not controlled they could potentially spread, and occupy 51, 77, 70%, respectively, of the first three catchments. At an annual expansion rate of 10–15% this would take about 13, 26 and 63 years, respectively. The invadable areas in the Sabie-Sand catchment are already invaded so invasions will only increase in density. It would take about 26–30 years to reach 100% canopy cover. The projected flow reductions for the four catchments would increase to 41.5, 95.5, 25.1 and 22.3%, respectively. The estimated cost of the control programmes to prevent these losses would be about US$ 13.2, 9.9, 4.1 and 6.6 million for the Sonderend, Keurbooms, Upper Wilge and Sabie-Sand catchments, respectively. Should the catchments be allowed to become fully invaded before control operations were started, then the costs would rise to US$ 86.5, 20.5, 278.0 and 11.1 million, respectively. The impacts and costs are significant and are comparable with those calculated independently for other South African catchments. Water is acknowledged to be a key constraint to economic growth in South Africa and there is considerable pressure for efficient and sustainable use of the limited water resources. The projected impacts would justify control programmes aimed at clearing alien invaders for water conservation. [Copyright &y& Elsevier]

The article presents a study on linkages among water vapor flows, agricultural food production, and terrestrial ecosystem services. Water vapor and liquid water are sometimes called green water and blue water, respectively. Blue water is the total runoff originating from the partitioning of precipitation at the land surface and the partitioning of soil water. Green water is the return flow of water to the atmosphere as evapotranspiration. The estimation of water vapor flows of major terrestrial biomes is discussed. Interrelations between water vapor flows and terrestrial ecosystem services is explained.

The article discusses components of fisheries management by Integrated Coastal Zone Management activities such as catchment rehabilitation and marine protected areas. It discusses goal and indices of the zone to improve environment for production in fisheries by maintaining habitats, ecosystem processes and biodiversity. It also mentions extension of management reverses shifts from long-lived to short-lived organisms and embrace elements of habitat protection for ecological concepts.

• In practice it is only possible to model and value a minority of ecosystem services. • Ecosystem service models need to address changes in habitat condition. • Modelling plus valuation needs further development for catchment decision making. Land produces a range of benefits, from ecosystem services, but markets only incentivise the production of a small proportion of them. The Ecosystem Approach develops plans for moving towards a more optimal mix. This requires stakeholders to understand the value of ecosystem services and how these values change with land-use and management. We investigate whether process-based modelling and economic valuation can help stakeholders to do this. We do this by applying these tools to a plan to improve ecosystem services delivery in a catchment. To be used in decision-support, analytical approaches need to be relatively inexpensive and rapid, and our analysis was deliberately constrained in this way. Two 25-year future scenarios were developed and compared against a baseline scenario. The first Designated Site scenario was based on enhancing the condition of nationally important nature conservation sites. The second, Ecosystem Services scenario, represented implementing the ecosystem services delivery plan. We modelled the change between the scenarios with an internationally recognised process based ecosystem services toolkit (the Land Use Capability Indicator, LUCI tool) and used the model outputs to inform economic valuation methods. Our selection of which ecosystem services to model and value were initially identified through a participatory approach. However those we could quantify was limited by evidence and data availability. We assessed changes in water quality (phosphorus load), sediment generation, carbon storage and flood regulation. We were able to put economic values on only carbon sequestration and flood regulation. Both the modelling results and the experience of applying the linked modelling-valuation approach are examined in the discussion to consider the limitations to the current usefulness of linking process based modelling to economic valuation for informing land management policy. We explore the origin and nature of these limitations and the key bottlenecks that need to be overcome, applicable to its use in other sites, regions and countries. This includes the availability of suitable coefficients and/or underlying data/evidence to parameterise the model, and the compatibility of model outputs with available economic valuation evidence (for value transfer). [ABSTRACT FROM AUTHOR]