Towards ecosystem accounts for Rwanda: Tracking 25 years of change in flows and potential supply of ecosystem services

Arapaima gigas stocks have declined drastically in the lower Tocantins River in the Amazon Microregion

Arapaima gigas, an emblematic species of the Amazon region and a longstanding primary fishing resource, currently holds a "Data Deficient" status on the International Union for Conservation of Nature Red List, and is listed as an endangered species in Brazil. The Tocantins River is the most extensively modified large tributary of the Amazon Basin, and thus can affect the dynamics of ichthyofaunal populations. Over a period of 1 year, representatives of the fishing communities and fishermen from 25 fishing communities from four municipalities in the lower Tocantins River region were interviewed, and the obtained information was evaluated based on the literature to survey the population abundance status of A. gigas in the region and its impact on local communities. Among the fishermen interviewed, only one reported still encountering and fishing A. gigas on Jaracuera Island. The disappearance of A. gigas in the region are viewed as having economically disastrous consequences for the residents. Additionally, other endemic fish species are no longer observed in this locality either. If fishery management officials do not work together with local communities, A. gigas could disappear from the northern region of Brazil, where information on the dynamics of A. gigas fishing is lacking.

Leveraging natural capital accounting to support businesses with nature-related risk assessments and disclosures

Nature loss threatens businesses, the global economy and financial stability. Understanding and addressing these risks for business will require credible measurement approaches and data. This paper explores how natural capital accounting (NCA) can support business data and information needs related to nature, including disclosures aligned with the Taskforce on Nature-related Financial Disclosures recommendations. As businesses seek to measure, manage and disclose their nature-related risks and opportunities, they will need well-organized, consistent and high-quality information regarding their dependencies and impacts on nature, which few businesses currently collect or track in-house. NCA may be useful for these purposes but has not been widely used or applied by businesses. National NCA guided by the U.N. System of Environmental-Economic Accounting may provide: (i) a useful framework for businesses in conceptualizing, organizing and managing nature-related data and statistics; and (ii) data and information that can directly support business disclosures, corporate NCA and other business applications. This paper explores these opportunities as well as synergies between national and corporate natural capital accounts. In addition, the paper discusses key barriers to advancing the wider use and benefits of NCA for business, including: awareness of NCA, data access, business capabilities related to NCA, spatial and temporal scales of data, audit and assurance considerations, potential risks, and costs and incentives. This article is part of the theme issue 'Bringing nature into decision-making'.

Trends in Ecosystem Services across Europe Due to Land-Use/Cover Changes

The growing pressure on society due to global change requires better integration of ecosystem services (ES) into decision-making. Despite a growing number of ES assessments, Europe-wide information on recent changes of multiple ES is still rare. This study aimed at analysing changes in ES values between 2000 and 2018 across Europe based on land use/land cover (LULC) distribution. We mapped 19 ES for 52 ecoregions and identified six major groups of ecoregions with similar LULC distribution and trends. Our results indicated that provisioning ES mainly increased in the forest-dominated region (G2), decreasing in the near-natural grassland region (G1), the region with agricultural mixed systems (G3), and the intensively-used steppic region (G6). Regulating ES slightly decreased in G1 and G6, but increased in G2 and the wetland-dominated region (G5). Cultural ES had generally low negative trends for most ecoregions. In addition, our results revealed ecoregions with differing trends in ES that could be related to specific socioeconomic developments. Our findings provide spatial and quantitative information that can be used for policy development at European national and regional levels—as well as for monitoring of ES.

Quantifying Land Use Land Cover Changes in the Lake Victoria Basin Using Satellite Remote Sensing: The Trends and Drivers between 1985 and 2014

The Lake Victoria Basin (LVB) is a significant resource for five states within East Africa, which faces major land use land cover changes that threaten ecosystem integrity and ecosystem services derived from the basin’s resources. To assess land use land cover changes between 1985 and 2014, and subsequently determine the trends and drivers of these changes, we used a series of Landsat images and field data obtained from the LVB. Landsat image pre-processing and band combinations were done in ENVI 5.1. A supervised classification was applied on 118 Landsat scenes using the maximum likelihood classifier in ENVI 5.1. The overall accuracy of classified images was computed for the 2014 images using 124 reference data points collected through stratified random sampling. Computations of area under various land cover classes were calculated between the 1985 and 2014 images. We also correlated the area from natural vegetation classes to farmlands and settlements (urban areas) to explore relationships between land use land cover conversions among these classes. Based on our land cover classifications, we obtained overall accuracy of 71% and a moderate Kappa statistic of 0.56. Our results indicate that the LVB has undergone drastic changes in land use land cover, mainly driven by human activities that led to the conversion of forests, woodlands, grasslands, and wetlands to either farmlands or settlements. We conclude that information from this work is useful not only for basin-scale assessments and monitoring of land cover changes but also for targeting, prioritizing, and monitoring of small scale, community led efforts to restore degraded and fragmented areas in the basin. Such efforts could mitigate the loss of ecosystem services previously derived from large contiguous land covers which are no longer tenable to restore. We recommend adoption of a basin scale, operational, Earth observation-based, land use change monitoring framework. Such a framework can facilitate rapid and frequent assessments of gains and losses in specific land cover classes and thus focus strategic interventions in areas experiencing major losses, through mitigation and compensatory approaches.

Assessment of Switchgrass-Based Bioenergy Supply Using GIS-Based Fuzzy Logic and Network Optimization in Missouri (U.S.A.)

Bioenergy has been globally recognized as one of the sustainable alternatives to fossil fuels. An assured supply of biomass feedstocks is a crucial bottleneck for the bioenergy industry emanating from uncertainties in land-use changes and future prices. Analytical approaches deriving from geographical information systems (GIS)-based analysis, mathematical modeling, optimization analyses, and empirical techniques have been widely used to evaluate the potential for bioenergy feedstock. In this study, we propose a three-phase methodology integrating fuzzy logic, network optimization, and ecosystem services assessment to estimate potential bioenergy supply. The fuzzy logic analysis uses multiple spatial criteria to identify suitable biomass cultivating regions. We extract spatial information based on favorable conditions and potential constraints, such as developed urban areas and croplands. Further, the network analysis uses the road network and existing biorefineries to evaluate feedstock production locations. Our analysis extends previous studies by incorporating biodiversity and ecologically sensitive areas into the analysis, as well as incorporating ecosystem service benefits as an additional driver for adoption, ensuring that biomass cultivation will minimize the negative consequences of large-scale land-use change. We apply the concept of assessing the potential for switchgrass-based bioenergy in Missouri to the proposed methodology.

Economic, land use, and ecosystem services impacts of Rwanda's Green Growth Strategy: An application of the IEEM+ESM platform

We develop and link the Integrated Economic-Environmental Modeling (IEEM) Platform to ecosystem services modeling (ESM). The IEEM+ESM Platform is an innovative decision-making framework for exploring complex public policy goals and elucidating synergies and trade-offs between alternative policy portfolios. The IEEM+ESM approach is powerful in its ability to shed light on (i) change in land use and ecosystem services driven by public policy and the supply and demand responses of businesses and households; and (ii) impacts on standard economic indicators of concern to Ministries of Finance such as gross domestic product and employment, as well as changes in wealth and ecosystem services. The IEEM+ESM approach is being adopted rapidly and by the end of 2020, IEEM+ESM Platforms will be implemented for about 25 countries. To demonstrate the insights generated by the IEEM+ESM approach, we apply it to the analysis of alternative green growth strategies in Rwanda, a country that has made strong progress in reducing poverty and enhancing economic growth in the last 15 years. The case of Rwanda is particularly compelling as it faces intense pressure on its natural capital base and ecosystem services, already with the highest population density in Africa, which is projected to double by 2050. In applying IEEM+ESM and comparing the outcomes of Rwanda's green growth policies, increasing fertilization of agricultural crops shows the largest economic gains but also trade-offs in environmental quality reflected through higher nutrient export and reduced water quality. Combining crop fertilization with forest plantations better balances critical ecosystem services and their role in underpinning economic development as Rwanda progresses toward its target of middle-income status by 2035. This application to Rwanda's green growth strategy demonstrates the value-added of the IEEM+ESM approach in generating results that speak to both economic outcomes and impacts on market and non-market ecosystem services.

Natural Capital Accounting for Land in Rwanda

Land, as a valuable natural resource, is an important pillar of Rwanda’s sustainable development. The majority of Rwanda’s 80% rural population rely on agriculture for their livelihood, and land is crucial for agriculture. However, since a high population density has made land a scarce commodity, growth in the agricultural sector and plans for rapid urbanisation are being constrained, and cross-sectoral trade-offs are becoming increasingly important, with a risk that long-term sustainability may be threatened if these trade-offs are not considered. To help track land value trends and assess trade-offs, and to help assess the sustainability of trends in land use and land cover, Rwanda has begun developing natural capital accounts for land in keeping with the United Nations’ System of Environmental-Economic Accounting. This paper reports on Rwanda’s progress with these accounts. The accounting approach adopted in our study measures changes in land use and land cover and quantifies stocks for the period under study (2014–2015). Rwanda is one of the first developing countries to develop natural capital accounts for land, but the wide range of possible uses in policy analysis suggests that such accounts could be useful for other countries as well.

Impacts of Climate Change on the Potential Productivity of Eleven Staple Crops in Rwanda

This study quantifies the potential responses of 11 staple crop yields to projected changes in temperature and precipitation in Rwanda, using a cross sectional model based on yield data collected across more than 14,000 villages. We incorporated a relatively high spatial resolution dataset on crop productivity, considered a broad range of crops relevant to national agricultural production priorities, used environmental data developed specifically for Rwanda, and reported uncertainty both from our estimation model and due to uncertainty in future climate projections. We estimate that future climate change will have the largest impacts on potential productivity of maize, bush bean, and Irish potato. All three crops are likely to experience a reduction in potential yields of at least 10% under Representative Concentration Pathway (RCP) 4.5 and at least 15% under RCP 8.5 by 2050. Notably, these are important crops nationally, and three of the crops targeted by Rwanda’s Crop Intensification Program. We find that the most severe reductions in potential crop yields will occur in the drier eastern savannah and plateau regions, but that the impacts of climate change could be neutral or even positive in the highlands through mid-century. The refined spatial scale of our analysis allows us to identify potentially vulnerable regions where adaptation investments may need to be prioritized to support food security and climate resilience in Rwanda’s agricultural sector.