Open Access Publications

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Open access publications by faculty, postdocs, and graduate students in the Department of Geography and Spatial Sciences.

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Sensor-based measurements of NDVI in small grain and corn fields by tractor, drone, and satellite platforms
(Crop and Environment, 2024-02-01) Miller, Jarrod O.; Mondal, Pinki; Sarupria, Manan
The use of sensors for variable rate nitrogen (VRN) applications is transitioning from equipment-based to drone and satellite technologies. However, regional algorithms, initially designed for proximal active sensors, require evaluation for compatibility with remotely sensed reflectance and N-rate predictions. This study observed normalized difference vegetation index (NDVI) data from six small grain and two corn fields over three years. We employed three platforms: tractor-mounted active sensors (T-NDVI), passive multispectral drone (D-NDVI), and satellite (S-NDVI) sensors. Averaged NDVI values were extracted from the as-applied equipment polygons. Correlations between NDVI values from the three platforms were positive and strong, with D-NDVI consistently recording the highest values, particularly in areas with lower plant biomass. This was attributed to D-NDVI's lower soil reflectance and its ability to measure the entire biomass within equipment polygons. For small grains, sensors spaced on equipment booms might not capture accurate biomass in poor-growing and low NDVI regions. Regarding VRN, S-NDVI and D-NDVI occasionally aligned with T-NDVI recommendations but often suggested half the active sensor rate. Final yields showed some correlation with landscape variables, irrespective of N application. This finding suggests the potential use of drone or satellite imagery to provide multiple NDVI maps before application, incorporating expected landscape responses and thereby enhancing VRN effectiveness.
Editorial: Transboundary conservation
(Frontiers in Conservation Science, 2024-01-24) Wang, Lin; Ali, Saleem H.; Thornton, Daniel H.; Farhadinia, Mohammad S.
Transboundary areas often contain critical ecosystems that support rich biodiversity and play important roles in maintaining ecological connectivity. More than half of terrestrial vertebrate species have ranges spanning international borders. Many species may shift their distributions by crossing international borders in response to climate change or human disturbances. Yet species in transboundary regions are in increasing peril due to uncoordinated management among neighboring countries and artificial barriers, such as walls and fences along borders and cross-border roads that result in habitat fragmentation and the loss of ecological connectivity. Transboundary conservation can significantly contribute to ongoing efforts to reduce the risk of future extinctions by expanding protected areas and promoting collaborative management. Therefore, more attention to this topic is urgently needed. The Research Topic of Transboundary Conservation aims to enhance understanding of the potential, patterns, and effects of transboundary conservation by collecting studies that analyze transboundary conservation across different terrestrial and marine landscapes. Simultaneously, it aspires towards broader goals of international environmental governance and security.
Estimating forest extent across Mexico
(Environmental Research Letters, 2024-01-12) Braden, Dustin; Mondal, Pinki; Park, Taejin; Alanís de la Rosa, José Armando; Aldrete Leal, Metzli Ileana; Cuenca Lara, Rubi Angélica; Mayorga Saucedo, Rafael; Paz, Fernando; Salas-Aguilar, Victor Manuel; Soriano-Luna, María De Los Ángeles; Vargas, Rodrigo
Information on forest extent and tree cover is required to evaluate the status of natural resources, conservation practices, and environmental policies. The challenge is that different forest definitions, remote sensing-based (RSB) products, and data availability can lead to discrepancies in reporting total forest area. Consequently, errors in forest extent can be propagated into forest biomass and carbon estimates. Here, we present a simple approach to compare forest extent estimates from seven regional and global land or tree cover RSB products at 30 m resolution across Mexico. We found substantial differences in forest extent estimates for Mexico, ranging from 387 607 km2 to 675 239 km2. These differences were dependent on the RSB product and forest definition used. Next, we compared these RSB products with two independent forest inventory datasets at national (n = 26 220 plots) and local scales (n = 754 plots). The greatest accuracy among RSB products and forest inventory data was within the tropical moist forest (range 82%–95%), and the smallest was within the subtropical desert (range <10%–80%) and subtropical steppe ecological zones (range <10%–60%). We developed a forest extent agreement map by combining seven RSB products and identifying a consensus in their estimates. We found a forest area of 288 749 km2 with high forest extent agreement, and 340 661 km2 with medium forest extent agreement. The high-to-medium forest extent agreement of 629 410 km2 is comparable to the official national estimate of 656 920 km2. We found a high forest extent agreement across the Yucatan Peninsula and mountain areas in the Sierra Madre Oriental and Sierra Madre Occidental. The tropical dry forest and subtropical mountain system represent the two ecological zones with the highest areas of disagreement among RSB products. These findings show discrepancies in forest extent estimates across ecological zones in Mexico, where additional ground data and research are needed. Dataset available at https://doi.org/10.3334/ORNLDAAC/2320.
Half of twenty-first century global irrigation expansion has been in water-stressed regions
(Nature Water, 2024-03-08) Mehta, Piyush; Siebert, Stefan; Kummu, Matti; Deng, Qinyu; Ali, Tariq; Marston, Landon; Xie, Wei; Davis, Kyle Frankel
The expansion of irrigated agriculture has increased global crop production but resulted in widespread stress on freshwater resources. Ensuring that increases in irrigated production occur only in places where water is relatively abundant is a key objective of sustainable agriculture and knowledge of how irrigated land has evolved is important for measuring progress towards water sustainability. Yet, a spatially detailed understanding of the evolution of the global area equipped for irrigation (AEI) is missing. In this study, we used the latest subnational irrigation statistics (covering 17,298 administrative units) from various official sources to develop a gridded (5 arcmin resolution) global product of AEI for the years 2000, 2005, 2010 and 2015. We found that AEI increased by 11% from 2000 (297 Mha) to 2015 (330 Mha), with areas of both substantial expansion, such as northwest India and northeast China, and decline, such as Russia. Combining these outputs with information on green (that is, rainfall) and blue (that is, surface and ground) water stress, we also examined to what extent irrigation has expanded unsustainably in places already experiencing water stress. We found that more than half (52%) of the irrigation expansion has taken place in areas that were already water-stressed in the year 2000, with India alone accounting for 36% of global unsustainable expansion. These findings provide new insights into the evolving patterns of global irrigation with important implications for global water sustainability and food security.
Assessing and addressing the global state of food production data scarcity
(Nature Reviews Earth & Environment, 2024-02-20) Kebede, Endalkachew Abebe; Abou Ali, Hanan; Clavelle, Tyler; Froehlich, Halley E.; Gephart, Jessica A.; Hartman, Sarah; Herrero, Mario; Kerner, Hannah; Mehta, Piyush; Nakalembe, Catherine; Ray, Deepak K.; Siebert, Stefan; Thornton, Philip; Davis, Kyle Frankel
Food production data — such as crop, livestock, aquaculture and fisheries statistics — are critical to achieving multiple sustainable development goals. However, the lack of reliable, regularly collected, accessible, usable and spatially disaggregated statistics limits an accurate picture of the state of food production in many countries and prevents the implementation of effective food system interventions. In this Review, we take stock of national and international food production data to understand its availability and limitations. Across databases, there is substantial global variation in data timeliness, granularity (both spatially and by food category) and transparency. Data scarcity challenges are most pronounced for livestock and aquatic food production. These challenges are largely concentrated in Central America, the Middle East and Africa owing to a combination of inconsistent census implementation and a global reliance on self-reporting. Because data scarcity is the result of technical, institutional and political obstacles, solutions must include technological and policy innovations. Fusing traditional and emerging data-gathering techniques with coordinated governance and dedicated long-term financing will be key to overcoming current obstacles to sustained, up-to-date and accurate food production data collection, foundational in promoting and monitoring progress towards healthier and more sustainable food systems worldwide.
Focus on the future of water-limited agricultural landscapes
(Environmental Research Letters, 2024-01-19) Peterson, Caitlin A.; Davis, Kyle Frankel; Dybala, Kristen E.; Fernández, Francisco J.; Ghimire, Rajan; Nidumolu, Uday; Roche, Rose
Water scarcity and related climate volatility are growing constraints on agricultural production landscapes around the world. While the adaptation options available are often dictated by system context, in many places broad-scale transformations are occurring in response to water-related pressures. We sought contributions from across regions, agricultural system types, and scientific disciplines to examine agricultural land use transitions driven by water scarcity, including the tradeoffs associated with alternative land uses; impacts on food production, environment, and society; innovations that can buffer risk; and considerations for planning and implementation. The research presented in this collection highlights the spectrum of policy and practice changes that are needed to facilitate beneficial land use transitions and system transformations, from quantifying risks, to evaluating multidimensional tradeoffs, to developing socio-technical policy bundles to maximize co-benefits.
The motivations, challenges and needs of small- and medium-scale beginning farmers in the midwestern United States
(Journal of Agriculture, Food Systems, and Community Development, 2023-04-27) Iles, Keri; Nixon, Rebecca; Ma, Zhao; Gibson, Kevin; Benjamin, Tamara
Beginning farmers are increasingly recognized as important agricultural actors in the United States. Efforts to help interested individuals enter agriculture have increased; however, there is still a substantial knowledge gap regarding beginning farmers’ characteristics, motivations to farm, challenges, and information and resource needs, particularly among those who operate small or medium-sized farms. In this research, we collected and analyzed survey data in Indiana to gain a better understanding of small- and medium-scale beginning farmers in the midwestern United States. We found that small- and medium-scale beginning farmers were motivated by their desire for a farming lifestyle and to support local food and agroecological farming systems on a landscape dominated by commodity crops. They relied substantially on off-farm income and faced related challenges including limited access to labor and difficulty balancing their on-farm and off-farm responsibilities. Finding effective marketing strategies also challenged this group of farmers, as they were not well-integrated into existing agricultural programs, and many had limited interactions with agricultural agencies and organizations. Instead, the majority of small- and medium-scale beginning farmers relied heavily on their own internet research and informal interactions with other farmers to learn and obtain help for their farms. Together, our results contribute to a better understanding of small- and medium-scale beginning farmers’ characteristics, motivations, and farming practices, as well as the challenges they face and the support they need to address these challenges. Because beginning farmers often differ from their more established counterparts who operate larger farms, the results of this research can be used to inform tailored agricultural programs and technical assistance that address small- and medium-scale beginning farmers’ specific needs and challenges in order to increase their likelihood of success to not only start but also sustain a small- or medium-scale farm over time.
Effects of forest thinning on sap flow dynamics and transpiration in a Japanese cedar forest
(Science of the Total Environment, 2023-12-20) Iida, Shin'ichi; Noguchi, Shoji; Levia, Delphis F.; Araki, Makoto; Nitta, Kyohei; Wada, Satoru; Narita, Yoshito; Tamura, Hiroki; Abe, Toshio; Kaneko, Tomonori
Historically, forest thinning in Japan was conducted to obtain high-quality timber from plantations. Today, in contrast, thinning is also motivated by forest water balance and climate change considerations. It is in this context that the present study examines the effects of thinning on the ecophysiological responses of remaining trees, which are inadequately understood, especially in relation to changes in the magnitude and duration of transpiration. Sap flux densities were measured in both outer and inner sapwood to obtain stand-scale transpiration for two years in the pre-thinning state and three years post-thinning. The effects of thinning on transpiration were quantitatively evaluated based on canopy conductance models. The larger increases in outer sap flux density were found in the first year after the treatment, while those in inner sap flux density were detected in the second and third years. The remaining trees required a few of years to adjust to improved light conditions of the lower crown, resulting in a delayed response of inner sap flux density. As a result of this lag, transpiration was reduced to 71 % of the pre-thinning condition in the first year, but transpiration recovered to the pre-thinning levels in the second and third years due to compensating contributions from inner sap flow. In terms of more accurately chronicling the thinning effect, the distribution of sap flux density with respect to its radial pattern, is necessary. Such measurements are key to more comprehensively examining the ecophysiological response of forest plantations to thinning and, ultimately, its effect on the forest water balance. Highlights • Transpiration (TR) was measured for two years before and three years post thinning. • Outer sap flux increased immediately, while inner increase was delayed. • TR decreased to 71 % just after thinning, returning to initial levels in 2–3 years. • Delayed but substantial increase of inner sap flow is a main factor for TR variation. • Both outer and inner sap fluxes must be quantified to evaluate thinning effects. Graphical abstract available at: https://doi.org/10.1016/j.scitotenv.2023.169060
Atmospheric Drivers Associated with Extreme Snow Ablation and Discharge Events in the Susquehanna River Basin: A Climatology
(Journal of Applied Meteorology and Climatology, 2023-11-02) Suriano, Zachary J.; Henderson, Gina R.; Arthur, Julia; Harper, Kricket; Leathers, Daniel J.
Extreme snow ablation can greatly impact regional hydrology, affecting streamflow, soil moisture, and groundwater supplies. Relatively little is known about the climatology of extreme ablation events in the eastern United States, and the causal atmospheric forcing mechanisms behind such events. Studying the Susquehanna River basin over a 50-yr period, here we evaluate the variability of extreme ablation and river discharge events in conjunction with a synoptic classification and global-scale teleconnection pattern analysis. Results indicate that an average of 4.2 extreme ablation events occurred within the basin per year, where some 88% of those events resulted in an increase in river discharge when evaluated at a 3-day lag. Both extreme ablation and extreme discharge events occurred most frequently during instances of southerly synoptic-scale flow, accounting for 35.7% and 35.8% of events, respectively. However, extreme ablation was also regularly observed during high pressure overhead and rain-on-snow synoptic weather types. The largest magnitude of snow ablation per extreme event occurred during occasions of rain-on-snow, where a basinwide, areal-weighted 5.7 cm of snow depth was lost, approximately 23% larger than the average extreme event. Interannually, southerly flow synoptic weather types were more frequent during winter seasons when the Arctic and North Atlantic Oscillations were positively phased. Approximately 30% of the variance in rain-on-snow weather type frequency was explained by the Pacific–North American pattern. Evaluating the pathway of physical forcing mechanisms from regional events up through global patterns allows for improved understanding of the processes resulting in extreme ablation and discharge across the Susquehanna basin. Significance Statement The purpose of this study is to better understand how certain weather patterns are related to extreme snowmelt and streamflow events and what causes those weather patterns to vary with time. This is valuable information for informing hazard preparation and resource management within the basin. We found that weather patterns with southerly winds were the most frequent patterns responsible for extreme melt and streamflow, and those patterns occurred more often when the Arctic and North Atlantic Oscillations were in their “positive” configuration. Future work should consider the potential for these patterns, and related impacts, to change over time.
Comparison of Extreme Coastal Flooding Events between Tropical and Midlatitude Weather Systems in the Delaware and Chesapeake Bays for 1980–2019
(Journal of Applied Meteorology and Climatology, 2022-04-26) Callahan, John A.; Leathers, Daniel J.; Callahan, Christina L.
Coastal flooding is one of the most costly and deadly natural hazards facing the U.S. mid-Atlantic region today. Impacts in this heavily populated and economically significant region are caused by a combination of the location’s exposure and natural forcing from storms and sea level rise. Tropical cyclones (TCs) and midlatitude (ML) weather systems each have caused extreme coastal flooding in the region. Skew surge was computed over each tidal cycle for the past 40 years (1980–2019) at several tide gauges in the Delaware and Chesapeake Bays to compare the meteorological component of surge for each weather type. Although TCs cause higher mean surges, ML weather systems can produce surges just as severe and occur much more frequently, peaking in the cold season (November–March). Of the top 10 largest surge events, TCs account for 30%–45% in the Delaware and upper Chesapeake Bays and 40%–45% in the lower Chesapeake Bay. This percentage drops to 10%–15% for larger numbers of events in all regions. Mean sea level pressure and 500-hPa geopotential height (GPH) fields of the top 10 surge events from ML weather systems show a low pressure center west-southwest of “Delmarva” and a semistationary high pressure center to the northeast prior to maximum surge, producing strong easterly winds. Low pressure centers intensify under upper-level divergence as they travel eastward, and the high pressure centers are near the GPH ridges. During lower-bay events, the low pressure centers develop farther south, intensifying over warmer coastal waters, with a south-shifted GPH pattern relative to upper-bay events. Significance Statement Severe coastal flooding is a year-round threat in the U.S. mid-Atlantic region, and impacts are projected to increase in magnitude and frequency. Research into the meteorological contribution to storm surge, separate from mean sea level and tidal phase, will increase the scientific understanding and monitoring of changing atmospheric conditions. Tropical cyclones and midlatitude weather systems both significantly impact the mid-Atlantic region during different times of year. However, climate change may alter the future behavior of these systems differently. Understanding the synoptic environment and quantifying the surge response and subbay geographic variability of each weather system in this region will aid in public awareness, near-term emergency preparation, and long-term planning for coastal storms.
SSP-Based Land-Use Change Scenarios: A Critical Uncertainty in Future Regional Climate Change Projections
(Earth's Future, 2021-03-25) Bukovsky, Melissa S.; Gao, Jing; Mearns, Linda O.; O'Neill, Brian C.
To better understand the role projected land-use changes (LUCs) may play in future regional climate projections, we assess the combined effects of greenhouse-gas (GHG)-forced climate change and LUCs in regional climate model (RCM) simulations. To do so, we produced RCM simulations that are complementary to the North-American Coordinated Regional Downscaling Experiment (NA-CORDEX) simulations, but with future LUCs that are consistent with particular Shared Socioeconomic Pathways (SSPs) and related to a specific Representative Concentration Pathway (RCP). We examine the state of the climate at the end of the 21st century with and without two urban and agricultural LUC scenarios that follow SSP3 and SSP5 using the Weather Research and Forecasting (WRF) model forced by one global climate model, the MPI-ESM, under the RCP8.5 scenario. We find that LUCs following different societal trends under the SSPs can significantly affect climate projections in different ways. In regions of significant cropland expansion over previously forested area, projected annual mean temperature increases are diminished by around 0.5°C–1.0°C. Across all seasons, where urbanization is high, projected temperature increases are magnified. In particular, summer mean temperature projections are up to 4°C–5°C greater and minimum and maximum temperature projections are increased by 2.5°C–6°C, amounts that are on par with the warming due to GHG-forced climate change. Warming is also enhanced in the urban surroundings. Future urbanization also has a large influence on precipitation projections during summer, increasing storm intensity, event length, and the overall amount over urbanized areas, and decreasing precipitation in surrounding areas. Key Points - Local-to-regional climate change projections of temperature and precipitation are strongly influenced by urban and agricultural land-use changes - Different shared-socioeconomic-pathway-informed land-use changes produce different responses in future regional climate changes - Urban land expansion has a greater influence on the contiguous United States climate change projections than agricultural land expansion Plain Language Summary In many regional climate change studies, projections of future climate conditions are produced assuming the current spatial distribution of different land cover types (e.g., urban, cropland, forest, etc.) will stay the same, even for long-term futures. In doing so, they neglect potential impacts of human land-use changes (LUCs) on regional climate, and miss the opportunity to identify potential land-use strategies that could moderate felt climate change effects. In this study, we model urban and agricultural LUCs following two pathways with different social and environmental trends throughout the 21st century, and investigate how the LUCs might affect climate change in North America. We find that future LUCs can strongly influence projections of temperature and precipitation. Generally, urban land expansion casted a larger impact than agricultural land expansion. In areas where croplands replace forests, the temperature increase caused by greenhouse gas warming is reduced, while in and near future urban areas, the temperature increase caused by greenhouses gas warming is doubled by warming effects from urban land expansion. Meanwhile, urban expansion enhances precipitation over urbanized areas making rainfall events heavier and longer, while precipitation in the surrounding areas is reduced.
Introduction: Managed retreat and environmental justice in a changing climate
(Journal of Environmental Studies and Sciences, 2021-05-15) Siders, A. R.; Ajibade, Idowu
In response to global climate change, managed retreat has emerged as a controversial adaptation strategy. The purposeful movement of people and communities away from hazardous places raises numerous social and environmental justice concerns that will become even more pressing as retreat occurs more frequently and at larger scales. This special issue contributes to an emerging body of literature on managed retreat by providing a range of perspectives and approaches to considering justice in managed retreat. The assembled papers represent diverse voices (including perspectives from individuals whose communities are currently relocating or considering relocation), disciplines (including oral histories, legal analyses, and cultural heritage considerations), and lenses through which to consider the justice implications of managed retreat. They describe completed, in-progress, and foiled relocations. They suggest opportunities for improvement through improved evaluations and broader collaborations. While each presents a unique lens, key themes emerge around the need for transparent and equitable policies, self-determination of communities, holistic metrics for assessing individual and community well-being, the importance of culture both as something to be protected and an asset to be leveraged, and the need to address historical and systemic injustices that contribute to vulnerability and exposure to risk.
Assessing urban heat-related adaptation strategies under multiple futures for a major U.S. city
(Climatic Change, 2021-02-27) Rohat, Guillaume; Wilhelmi, Olga; Flacke, Johannes; Monaghan, Andrew; Gao, Jing; van Maarseveen, Martin; Dao, Hy
Urban areas are increasingly affected by extreme heat in the face of climate change, while the size and vulnerability of exposed populations are shifting due to economic development, demographic change, and urbanization. In addition to the need to assess future urban heat-related health risks, there is also an increasing need to design adaptation strategies that will be effective under varying levels of socioeconomic development and climate change. We use the case study of Houston, Texas, to develop and demonstrate a scenario-based approach to explore the effectiveness of both autonomous and planned heat-related adaptations under multiple plausible futures. We couple a heat risk model with urban climate projections (under the Representative Concentration Pathways) and vulnerability projections (under locally extended Shared Socioeconomic Pathways) to investigate the impact of different adaptation strategies under multiple scenario combinations. We demonstrate that, in the context of Houston, community-based adaptation strategies aiming to reduce social isolation are the most effective and the least challenging to implement across all plausible futures. Scenario-based approaches can provide local policymakers with context-specific assessments of possible adaptation strategies that account for uncertain futures.
Social media analysis reveals environmental injustices in Philadelphia urban parks
(Scientific Reports, 2023-08-03) Walter, Matthew; Bagozzi, Benjamin E.; Ajibade, Idowu; Mondal, Pinki
The United Nations Sustainable Development Goal (SDG) target 11.7 calls for access to safe and inclusive green spaces for all communities. Yet, historical residential segregation in the USA has resulted in poor quality urban parks near neighborhoods with primarily disadvantaged socioeconomic status groups, and an extensive park system that addresses the needs of primarily White middle-class residents. Here we center the voices of historically marginalized urban residents by using Natural Language Processing and Geographic Information Science to analyze a large dataset (n = 143,913) of Google Map reviews from 2011 to 2022 across 285 parks in the City of Philadelphia, USA. We find that parks in neighborhoods with a high number of residents from historically disadvantaged demographic groups are likely to receive lower scores on Google Maps. Physical characteristics of these parks based on aerial and satellite images and ancillary data corroborate the public perception of park quality. Topic modeling of park reviews reveal that the diverse environmental justice needs of historically marginalized communities must be met to reduce the uneven park quality—a goal in line with achieving SDG 11 by 2030.
Competition for water induced by transnational land acquisitions for agriculture
(Nature Communications, 2022-01-26) Chiarelli, Davide Danilo; D’Odorico, Paolo; Müller, Marc F.; Mueller, Nathaniel D.; Davis, Kyle Frankel; Dell’Angelo, Jampel; Penny, Gopal; Rulli, Maria Cristina
The ongoing agrarian transition from smallholder farming to large-scale commercial agriculture promoted by transnational large-scale land acquisitions (LSLAs) often aims to increase crop yields through the expansion of irrigation. LSLAs are playing an increasingly prominent role in this transition. Yet it remains unknown whether foreign LSLAs by agribusinesses target areas based on specific hydrological conditions and whether these investments compete with the water needs of existing local users. Here we combine process-based crop and hydrological modelling, agricultural statistics, and georeferenced information on individual transnational LSLAs to evaluate emergence of water scarcity associated with LSLAs. While conditions of blue water scarcity already existed prior to land acquisitions, these deals substantially exacerbate blue water scarcity through both the adoption of water-intensive crops and the expansion of irrigated cultivation. These effects lead to new rival water uses in 105 of the 160 studied LSLAs (67% of the acquired land). Combined with our findings that investors target land with preferential access to surface and groundwater resources to support irrigation, this suggests that LSLAs often appropriate water resources to the detriment of local users.
Key role of planted and harvested area fluctuations in US crop production shocks
(Nature Sustainability, 2023-06-15) Wei, Dongyang; Gephart, Jessica A.; Iizumi, Toshichika; Ramankutty, Navin; Davis, Kyle Frankel
Food production stability against climate variability and extremes is crucial for food security and is influenced by variations in planted area, harvested area and yield. Yet research has focused on yield responses to climate fluctuations, ignoring how planted area and harvestable fraction (that is, the ratio of planted area to harvested area) affect production stability. Here we apply a time series shock detection approach to county-level data (1978–2020) on seven crops in the United States, finding that shocks (that is, sudden statistically significant declines) in planted area and harvestable fraction co-occur with 51–81% of production shocks, depending on the crop. Decomposing production shock magnitudes, we find that yield fluctuations contribute more for corn (59%), cotton (49%), soybean (64%) and winter wheat (40%), whereas planted area and harvestable fraction have a greater role for others. Additionally, climatic variables explain considerable portions of the variance in planted area (22–30%), harvestable fraction (15–28%) and yield (32–50%). These findings demonstrate that crop production shocks are often associated with fluctuations in planted area and harvestable fraction. This highlights the (largely ignored) importance of producer decision-making about cropping patterns in stabilizing food production against climate variability and emphasizes the need to consider all three production components to improve food system stability.
Crop switching can enhance environmental sustainability and farmer incomes in China
(Nature, 2023-03-16) Xie, Wei; Zhu, Anfeng; Ali, Tariq; Zhang, Zhengtao; Chen, Xiaoguang; Wu, Feng; Huang, Jikun; Davis, Kyle Frankel
Achieving food-system sustainability is a multidimensional challenge. In China, a doubling of crop production since 1990 has compromised other dimensions of sustainability1,2. Although the country is promoting various interventions to enhance production efficiency and reduce environmental impacts3, there is little understanding of whether crop switching can achieve more sustainable cropping systems and whether coordinated action is needed to avoid tradeoffs. Here we combine high-resolution data on crop-specific yields, harvested areas, environmental footprints and farmer incomes to first quantify the current state of crop-production sustainability. Under varying levels of inter-ministerial and central coordination, we perform spatial optimizations that redistribute crops to meet a suite of agricultural sustainable development targets. With a siloed approach—in which each government ministry seeks to improve a single sustainability outcome in isolation—crop switching could realize large individual benefits but produce tradeoffs for other dimensions and between regions. In cases of central coordination—in which tradeoffs are prevented—we find marked co-benefits for environmental-impact reductions (blue water (−4.5% to −18.5%), green water (−4.4% to −9.5%), greenhouse gases (GHGs) (−1.7% to −7.7%), fertilizers (−5.2% to −10.9%), pesticides (−4.3% to −10.8%)) and increased farmer incomes (+2.9% to +7.5%). These outcomes of centrally coordinated crop switching can contribute substantially (23–40% across dimensions) towards China’s 2030 agricultural sustainable development targets and potentially produce global resource savings. This integrated approach can inform feasible targeted agricultural interventions that achieve sustainability co-benefits across several dimensions.
Fair trade rebels : coffee production and struggles for autonomy in Chiapas
(University Of Minnesota Press, 2019-12-10) Naylor, Lindsay
Is fair trade really fair? Who is it for, and who gets to decide? Fair Trade Rebels addresses such questions in a new way by shifting the focus from the abstract concept of fair trade—and whether it is “working”—to the perspectives of small farmers. It examines the everyday experiences of resistance and agricultural practice among the campesinos/as of Chiapas, Mexico, who struggle for dignified livelihoods in self-declared autonomous communities in the highlands, confronting inequalities locally in what is really a global corporate agricultural chain. Based on extensive fieldwork, Fair Trade Rebels draws on stories from Chiapas that have emerged from the farmers’ interaction with both the fair-trade–certified marketplace and state violence. Here Lindsay Naylor discusses the racialized and historical backdrop of coffee production and rebel autonomy in the highlands, underscores the divergence of movements for fairer trade and the so-called alternative certified market, traces the network of such movements from the highlands and into the United States, and evaluates existing food sovereignty and diverse economic exchanges. Putting decolonial thinking in conversation with diverse economies theory, Fair Trade Rebels evaluates fair trade not by the measure of its success or failure but through a unique, place-based approach that expands our understanding of the relationship between fair trade, autonomy, and economic development.
Adaptation to compound climate risks: A systematic global stocktake
(iScience, 2023-02-17) Simpson, Nicholas P.; Williams, Portia Adade; Mach, Katharine J.; Berrang-Ford, Lea; Biesbroek, Robbert; Haasnoot, Marjolijn; Segnon, Alcade C.; Campbell, Donovan; Musah-Surugu, Justice Issah; Joe, Elphin Tom; Nunbogu, Abraham Marshall; Sabour, Salma; Meyer, Andreas L.S.; Andrews, Talbot M.; Singh, Chandni; Siders, A.R.; Lawrence, Judy; van Aalst, Maarten; Trisos, Christopher H.; The Global Adaptation Mapping Initiative Team
Highlights: • Compound climate impacts are particularly hard to adapt to • Compound vulnerabilities and exposures constrain adaptation capabilities • Inappropriate responses to climate change can lead to maladaptation • Compound impacts can have cascading effects on response options Summary: This article provides a stocktake of the adaptation literature between 2013 and 2019 to better understand how adaptation responses affect risk under the particularly challenging conditions of compound climate events. Across 39 countries, 45 response types to compound hazards display anticipatory (9%), reactive (33%), and maladaptive (41%) characteristics, as well as hard (18%) and soft (68%) limits to adaptation. Low income, food insecurity, and access to institutional resources and finance are the most prominent of 23 vulnerabilities observed to negatively affect responses. Risk for food security, health, livelihoods, and economic outputs are commonly associated risks driving responses. Narrow geographical and sectoral foci of the literature highlight important conceptual, sectoral, and geographic areas for future research to better understand the way responses shape risk. When responses are integrated within climate risk assessment and management, there is greater potential to advance the urgency of response and safeguards for the most vulnerable. Graphical abstract at: https://doi.org/10.1016/j.isci.2023.105926
Transnational agricultural land acquisitions threaten biodiversity in the Global South
(Environmental Research Letters, 2023-02-02) Davis, Kyle Frankel; Müller, Marc F.; Rulli, Maria Cristina; Tatlhego, Mokganedi; Ali, Saleem; Baggio, Jacopo A.; Dell'Angelo, Jampel; Jung, Suhyun; Kehoe, Laura; Niles, Meredith T.; Eckert, Sandra
Agricultural large-scale land acquisitions have been linked with enhanced deforestation and land use change. Yet the extent to which transnational agricultural large-scale land acquisitions (TALSLAs) contribute to—or merely correlate with—deforestation, and the expected biodiversity impacts of the intended land use changes across ecosystems, remains unclear. We examine 178 georeferenced TALSLA locations in 40 countries to address this gap. While forest cover within TALSLAs decreased by 17% between 2000 and 2018 and became more fragmented, the spatio-temporal patterns of deforestation varied substantially across regions. While deforestation rates within initially forested TALSLAs were 1.5 (Asia) to 2 times (Africa) higher than immediately surrounding areas, we detected no such difference in Europe and Latin America. Our findings suggest that, whereas TALSLAs may have accelerated forest loss in Asia, a different mechanism might emerge in Africa where TALSLAs target areas already experiencing elevated deforestation. Regarding biodiversity (here focused on vertebrate species), we find that nearly all (91%) studied deals will likely experience substantial losses in relative species richness (−14.1% on average within each deal)—with mixed outcomes for relative abundance—due to the intended land use transitions. We also find that 39% of TALSLAs fall at least partially within biodiversity hotspots, placing these areas at heightened risk of biodiversity loss. Taken together, these findings suggest distinct regional differences in the nature of the association between TALSLAs and forest loss and provide new evidence of TALSLAs as an emerging threat to biodiversity in the Global South.

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