Quantifying the dynamics of land use change is critical in tackling global societal challenges such as food security, climate change, and biodiversity loss. Here we analyse the dynamics of global ...land use change at an unprecedented spatial resolution by combining multiple open data streams (remote sensing, reconstructions and statistics) to create the HIstoric Land Dynamics Assessment + (HILDA +). We estimate that land use change has affected almost a third (32%) of the global land area in just six decades (1960-2019) and, thus, is around four times greater in extent than previously estimated from long-term land change assessments. We also identify geographically diverging land use change processes, with afforestation and cropland abandonment in the Global North and deforestation and agricultural expansion in the South. Here, we show that observed phases of accelerating (~1960-2005) and decelerating (2006-2019) land use change can be explained by the effects of global trade on agricultural production.
Model‐based global projections of future land‐use and land‐cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to ...provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global‐scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.
Losses at every stage in the food system influence the extent to which nutritional requirements of a growing global population can be sustainably met. Inefficiencies and losses in agricultural ...production and consumer behaviour all play a role. This paper aims to understand better the magnitude of different losses and to provide insights into how these influence overall food system efficiency. We take a systems view from primary production of agricultural biomass through to human food requirements and consumption. Quantities and losses over ten stages are calculated and compared in terms of dry mass, wet mass, protein and energy. The comparison reveals significant differences between these measurements, and the potential for wet mass figures used in previous studies to be misleading. The results suggest that due to cumulative losses, the proportion of global agricultural dry biomass consumed as food is just 6% (9.0% for energy and 7.6% for protein), and 24.8% of harvest biomass (31.9% for energy and 27.8% for protein). The highest rates of loss are associated with livestock production, although the largest absolute losses of biomass occur prior to harvest. Losses of harvested crops were also found to be substantial, with 44.0% of crop dry matter (36.9% of energy and 50.1% of protein) lost prior to human consumption. If human over-consumption, defined as food consumption in excess of nutritional requirements, is included as an additional inefficiency, 48.4% of harvested crops were found to be lost (53.2% of energy and 42.3% of protein). Over-eating was found to be at least as large a contributor to food system losses as consumer food waste. The findings suggest that influencing consumer behaviour, e.g. to eat less animal products, or to reduce per capita consumption closer to nutrient requirements, offer substantial potential to improve food security for the rising global population in a sustainable manner.
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•Food system losses quantified from primary production to human food requirements.•Global agricultural dry biomass consumed as food is 6% (energy 9.0% and protein 7.6%).•44% of harvested crops dry matter lost prior to human consumption.•Highest loss rate in livestock production, but largest losses before harvest•Over-eating at least as large a contributor to food system losses as consumer waste.
•New index (HALF) quantifying the effects of diet on agricultural land use area.•14-fold range assuming global adoption of current country-level average diets.•Half current area if average Indian ...diet adopted, but nearly 3-time for diet in USA.•Types of food commodities in diets more important factor than the quantity.•Area for waste with USA consumption patterns twice that for complete Indian diet.
Human appropriation of land for food production has fundamentally altered the Earth system, with impacts on water, soil, air quality, and the climate system. Changes in population, dietary preferences, technology and crop productivity have all played important roles in shaping today’s land use. In this paper, we explore how past and present developments in diets impact on global agricultural land use. We introduce an index for the Human Appropriation of Land for Food (HALF), and use it to isolate the effects of diets on agricultural land areas, including the potential consequences of shifts in consumer food preferences. We find that if the global population adopted consumption patterns equivalent to particular current national per capita rates, agricultural land use area requirements could vary over a 14-fold range. Within these variations, the types of food commodities consumed are more important than the quantity of per-capita consumption in determining the agricultural land requirement, largely due to the impact of animal products and in particular ruminant species. Exploration of the average diets in the USA and India (which lie towards but not at global consumption extremes) provides a framework for understanding land use impacts arising from different food consumption habits. Hypothetically, if the world were to adopt the average Indian diet, 55% less agricultural land would be needed to satisfy demand, while global consumption of the average USA diet would necessitate 178% more land. Waste and over-eating are also shown to be important. The area associated with food waste, including over-consumption, given global adoption of the consumption patterns of the average person in the USA, was found to be twice that required for all food production given an average Indian per capita consumption. Therefore, measures to influence future diets and reduce food waste could substantially contribute towards global food security, as well as providing climate change mitigation options.
Understanding how farmers perceive climate change risks and how this affects their willingness to adopt adaptation practices is critical for developing effective climate change response strategies ...for the agricultural sector. This study examines (i) the perceptual relationships between farmers' awareness of climate change phenomena, beliefs in climate change risks and actual adaptation behaviour, and (ii) how these relationships may be modified by farm-level antecedents related to human, social, financial capitals and farm characteristics. An extensive household survey was designed to investigate the current pattern of adaptation strategies and collect data on these perceptual variables and their potential antecedents from private landowners in Veszprém and Tolna counties, Hungary. Path analysis was used to explore the causal connections between variables. We found that belief in the risk of climate change was heightened by an increased awareness of directly observable climate change phenomena (i.e. water shortages and extreme weather events). The awareness of extreme weather events was a significant driver of adaptation behaviour. Farmers’ actual adaptation behaviour was primarily driven by financial motives and managerial considerations (i.e. the aim of improving profit and product sales; gaining farm ownership and the amount of land managed; and, the existence of a successor), and stimulated by an innovative personality and the availability of information from socio-agricultural networks. These results enrich the empirical evidence in support of improving understanding of farmer decision-making processes, which is critical in developing well-targeted adaptation policies.
•Farmers' perception of, and adaptation to, climate change in Hungary is investigated.•Adaptation behaviour is motivated by the awareness of extreme weather events.•Adaptation behaviour is primarily driven by financial and managerial motives.•Study sheds light on farmers' decision-making mechanisms.•Our results contribute to the development of well-targeted adaptation policies.
•Quantifies global agricultural land use change and drivers, including pasture.•Land for animal products has dominated land use change (65%) over the past 50 years.•Drivers for land shifting from ...population expansion towards changes in diets.•Rate of extensification in area for animal production has reduced since mid-1990s.•Bioenergy area relatively small, but substantial part of net agricultural expansion.
The nexus of population growth and changing diets has increased the demands placed on agriculture to supply food for human consumption, animal feed and fuel. Rising incomes lead to dietary changes, from staple crops, towards commodities with greater land requirements, e.g. meat and dairy products. Despite yield improvements partially offsetting increases in demand, agricultural land has still been expanding, causing potential harm to ecosystems, e.g. through deforestation. We use country-level panel data (1961–2011) to allocate the land areas used to produce food for human consumption, waste and biofuels, and to attribute the food production area changes to diet, population and yields drivers. The results show that the production of animal products dominates agricultural land use and land use change over the 50-year period, accounting for 65% of land use change. The rate of extensification of animal production was found to have reduced more recently, principally due to the smaller effect of population growth. The area used for bioenergy was shown to be relatively small, but formed a substantial contribution (36%) to net agricultural expansion in the most recent period. Nevertheless, in comparison to dietary shifts in animal products, bioenergy accounted for less than a tenth of the increase in demand for agricultural land. Population expansion has been the largest driver for agricultural land use change, but dietary changes are a significant and growing driver. China was a notable exception, where dietary transitions dominate food consumption changes, due to rapidly rising incomes. This suggests that future dietary changes will become the principal driver for land use change, pointing to the potential need for demand-side measures to regulate agricultural expansion.
•Research is developing on links between ecosystem services and poverty alleviation.•We review the contribution of 9 frameworks to this research agenda.•We highlight frameworks recognizing social ...differentiation and constrained access.•We highlight differences between categories of services and contributions to wellbeing.•We note the limited contribution of ecosystem services to poverty alleviation.
A research agenda is currently developing around the linkages between ecosystem services and poverty alleviation. It is therefore timely to consider which conceptual frameworks can best support research at this nexus. Our review of frameworks synthesises existing research on poverty/environment linkages that should not be overlooked with the adoption of the topical language of ecosystem services. A total of nine conceptual frameworks were selected on the basis of relevance. These were reviewed and compared to assess their ability to illuminate the provision of ecosystem services, the condition, determinants and dynamics of poverty, and political economy factors that mediate the relationship between poverty and ecosystem services. The paper synthesises the key contributions of each of these frameworks, and the gaps they expose in one another, drawing out lessons that can inform emerging research. Research on poverty alleviation must recognize social differentiation, and be able to distinguish between constraints of access and constraints of aggregate availability of ecosystem services. Different frameworks also highlight important differences between categories of services, their pathways of production, and their contribution to poverty alleviation. Furthermore, we highlight that it is important to acknowledge the limits of ecosystem services for poverty alleviation, given evidence that ecosystem services tend to be more associated with poverty prevention than reduction. We conclude by reflecting on the relative merits of dynamic Social–Ecological Systems frameworks versus more static checklists, and suggest that research on ecosystem services and poverty alleviation would be well served by a new framework distilling insights from the frameworks we review.
A single target comparable to the 2°C climate target may help galvanize biodiversity policy
Although worldwide loss of biodiversity arising from human activities is widely known, policy has been ...unable to arrest the decline (
1
). Much of this failure can be attributed to a lack of mainstreaming of biodiversity in public policy (2, pp. 741–762) and limitations in raising the profile of biodiversity loss for politicians and the public. Of the 20 Aichi Biodiversity Targets (ABTs) established in 2010 by the Convention on Biodiversity (CBD), only four show good progress, whereas 12 related to the state of nature show worsening trends (
1
). With the 2020 target date for the ABTs now upon us, it is critical to define a post-2020 agenda to arrest the loss of biodiversity. This will require a target, underpinned by a clear global goal for biodiversity, that can be readily communicated to galvanize both political will and public support. Similarly to how the climate change community uses a single indicator (global mean temperature change) and a target (maximum 2°C rise relative to preindustrial levels) as a rallying point for policy action and agreements, we propose a 2°C-like target for biodiversity (see table S1): a measurable, near-term target of keeping described species extinctions to well below 20 per year over the next 100 years across all major groups (fungi, plants, invertebrates, and vertebrates) and across all ecosystem types (marine, freshwater, and terrestrial).
INTRODUCTION: Land exchange can be a major factor driving land-use change in regions with high pressure on land, but is generally not incorporated in land-use change models. Here we present an ...agent-based model to simulate land-use change arising from land exchange between multiple agent types representing farmers, nature organizations, and estate owners. METHODS: The RULEX model (Rural Land EXchange) was calibrated and applied to a 300 km²case study area in the east of the Netherlands. Decision rules about which actor will sell and buy land, as well as which specific land to buy or sell are based on historical observations, interviews, and choice experiments. RESULTS: A reconstruction of land-use change for the period 2001–2009 demonstrates that RULEX reproduces most observed land-use trends and patterns. Given that RULEX simulates only one mechanism of land-use change, i.e. land exchange, it is conservative in simulating change. CONCLUSIONS: With this model, we demonstrate the potential of incorporating land market processes in an agent-based, land-use change model. This supports understanding of land-use change that is brought about by ownership change, which is an important process in areas where pressure on land is high. The soundness of the process representation was corroborated by stakeholders within the study area. Land exchange models can be used to assess the impact of changes in climate, markets, and policy on land use change, and help to increase effectiveness of alternative land purchasing strategies by stakeholders or spatial planning policy.
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