Tyler Lark

University of Wisconsin–Madison | UW · Center for Sustainability and the Global Environment (SAGE)

The land that is potentially available to produce dedicated cellulosic bioenergy crops, often referred to as ‘marginal’ land, depends heavily on the underlying assumptions used to classify and identify it. In this study we compare three definitions and types of marginal land to identify the interactions between the bioenergy landscape and the logis...

The opportunity of agricultural management practices to sequester soil organic carbon (SOC) is recognized as an important strategy for mitigating climate change. However, there is low confidence when it comes to understanding the magnitude of the climate benefit we can expect from SOC sequestration or how best to achieve it. Several issues are ofte...

Existing estimates of the climate mitigation potential from cropland carbon sequestration (C‐sequestration) are limited because they tend to assume constant rates of soil organic carbon change over all available cropland area, use relatively coarse land delineations, and often fail to adequately consider the agronomic and socioeconomic dimensions o...

To help young people understand socio-environmental systems and develop the confidence that meaningful action can be taken to address socio-environmental problems, young people need interactive simulations that enable them to take consequential actions in a familiar context and see the results. This can be achieved through reduced-form models with...

Knowing where and when croplands have been abandoned is fundamental to evaluating future uses of these areas, e.g., as sites for ecological restoration, recultivation, bioenergy production, or other uses. However, there is large uncertainty about the location and timing of cropland abandonment and how this process and the availability of associated...

The Renewable Fuel Standard (RFS) is the primary policy governing the use of biofuels in the United States. Following the 2007 enactment of the RFS, there has been substantial expansion in the use of cropland to produce biofuel feedstocks, including corn and soybeans. Both the conversion of land and the ongoing cultivation of these crops can, depen...

Urbanization imperils agriculture by converting farmland into uncultivable impervious surfaces and other uses that limit land productivity. Despite the considerable loss of productive croplands due to historic urbanization in the United States, little is known about the locations and magnitudes of extant agricultural land still under threat of futu...

Energy crops for biofuel production, especially switchgrass (Panicum virgatum), are of interest from a climate change perspective. Here, we use outputs from a crop growth model and life cycle assessment (LCA) to examine the global warming intensity (GWI; g CO2 MJ⁻¹) and greenhouse gas (GHG) mitigation potential (Mg CO2 year⁻¹) of biofuel systems ba...

Transitioning to a sustainable energy system poses a massive challenge to communities, nations, and the global economy in the next decade and beyond. A growing portfolio of satellite data products is available to support this transition. Satellite data complement other information sources to provide a more complete picture of the global energy syst...

Taheripour et al. recently posted comments on their websites about our peer-reviewed study published in the Proceedings of the National Academy of Sciences (Lark et al. 2022). We found Taheripour et al.’s conclusions to be unsupported and based upon several misunderstandings and misinterpretations of our methods and results. To help clarify, we wro...

Significance Biofuels are included in many proposed strategies to reduce anthropogenic greenhouse gas emissions and limit the magnitude of global warming. The US Renewable Fuel Standard is the world’s largest existing biofuel program, yet despite its prominence, there has been limited empirical assessment of the program’s environmental outcomes. Ev...

Data on irrigation patterns and trends at field-level detail across broad extents are vital for assessing and managing limited water resources. Until recently, there has been a scarcity of comprehensive, consistent, and frequent irrigation maps for the US. Here we present the new Landsat-based Irrigation Dataset (LANID), which is comprised of 30 m...

Recognizing the substantial threats climate change poses to agricultural supply chains, companies around the world are committing to reducing greenhouse gas (GHG) emissions. Recent modeling advances have increased the transparency of meat and ethanol industry supply chains, where conventional production practices and associated environmental impact...

In their recent contribution, Scully et al (2021 Environ. Res. Lett. 16 043001) review and revise past life cycle assessments of corn-grain ethanol's carbon (C) intensity to suggest that a current 'central best estimate' is considerably less than all prior estimates. Their conclusion emerges from selection and recombination of sector-specific green...

Marginal land has received wide attention for its potential to produce bioenergy feedstocks while minimizing diversion of productive agricultural land from food crop production. However, there has been no consensus in the literature on how to define or identify land that is marginal for food crops and beneficial for bioenergy crops. Studies have us...

Identifying the location of irrigated croplands and how they change over time is critical for assessing and managing limited water resources to navigate such challenges as local to global water scarcity, increasing demands for food and energy production, and environmental sustainability. Although efforts have been made to map irrigated area for the...

Data on irrigation patterns and trends at field-level detail across broad extents is vital for assessing and managing limited water resources. Until recently, there has been a scarcity of comprehensive, consistent, and frequent irrigation maps for the U.S. Here we present the new Landsat-based Irrigation Dataset (LANID), which is comprised of 30-m...

Alongside the steep reductions needed in fossil fuel emissions, natural climate solutions (NCS) represent readily deployable options that can contribute to Canada’s goals for emission reductions. We estimate the mitigation potential of 24 NCS related to the protection, management, and restoration of natural systems that can also deliver numerous co...

The Missouri River Basin (MORB) in the US has experienced a resurgence of grassland conversion to crop production, due in part to biofuel feedstock production of corn and soybeans. This conversion has raised concerns on water quality and ecosystems. Therefore, we applied the Soil and Water Assessment Tool (SWAT) to the MORB to address how this conv...

Scully et al [1] in their recent contribution review and revise past life cycle assessments (LCAs) of corn-grain ethanol’s carbon (C) intensity to suggest that a current ‘central best estimate’ is considerably less than all prior estimates. Their conclusion emerges from selection and recombination of sector-specific greenhouse gas emission predicti...

After decades of declining cropland area, the United States (US) experienced a reversal in land use/land cover change in recent years, with substantial grassland conversion to cropland in the US Midwest. Although previous studies estimated soil carbon (C) loss due to cropland expansion, other important environmental indicators, such as soil erosion...

The U.S. Department of Agriculture’s (USDA) Cropland Data Layer (CDL) is a 30 m resolution crop-specific land cover map produced annually to assess crops and cropland area across the conterminous United States. Despite its prominent use and value for monitoring agricultural land use/land cover (LULC), there remains substantial uncertainty surroundi...

Recent expansion of croplands in the United States has caused widespread conversion of grasslands and other ecosystems with largely unknown consequences for agricultural production and the environment. Here we assess annual land use change 2008-16 and its impacts on crop yields and wildlife habitat. We find that croplands have expanded at a rate of...

Grasslands are among the most endangered ecosystems in the world. They supply vital resources for society, support an abundance of wildlife species, and store rich carbon reserves beneath their surfaces. Despite this, only a fraction of original grasslands in the United States now remains, and their rate of conversion to cropland has recently reacc...

Remotely sensed biomass carbon density maps are widely used for myriad scientific and policy applications, but all remain limited in scope. They often only represent a single vegetation type and rarely account for carbon stocks in belowground biomass. To date, no global product integrates these disparate estimates into an all-encompassing map at a...

Accurate and timely information on the distribution of irrigated croplands is crucial to research on agriculture, water availability, land use, and climate change. While agricultural land use has been well characterized, less attention has been paid specifically to croplands that are irrigated, in part due to the difficulty in mapping and distingui...

After decades of decline, croplands are once again expanding across the United States. A 11 recent spatially explicit analysis mapped nearly three million hectares of US cropland expansion 12 that occurred between 2008 and 2012. Land use change (LUC) of this sort can be a major source 13 of anthropogenic carbon (C) emissions, though the effects of...

Unplowed native grasslands are among the most endangered ecosystems in the world, due in large part to their agricultural suitability and widespread conversion to cropland. Despite this, remaining locations of these species- and carbon-rich landscapes are neither well monitored nor effectively protected. A recent spike in US prices for corn ( Zea m...

Limiting climate warming to <2°C requires increased mitigation efforts, including land stewardship, whose potential in the United States is poorly understood. We quantified the potential of natural climate solutions (NCS)—21 conservation, restoration, and improved land management interventions on natural and agricultural lands—to increase carbon st...

Management of public lands, and who should have access to them, is often contentious. Most ranches in the western US rely upon seasonal grazing access to public lands, and conflict over biodiversity management has led to proposals to restrict grazing access on public lands. We evaluate whether grazing restrictions on public rangelands could have th...

Monitoring agricultural land is important for understanding and managing food production, environmental conservation efforts, and climate change. The United States Department of Agriculture's Cropland Data Layer (CDL), an annual satellite imagery-derived land cover map, has been increasingly used for this application since complete coverage of the...

Although the United States has pursued rapid development of corn ethanol as a matter of national biofuel policy, relatively little is known about this policy's widespread impacts on agricultural land conversion surrounding ethanol refineries. This knowledge gap impedes policy makers' ability to identify and mitigate potentially negative environment...

Cultivation of corn and soybeans in the United States reached record high levels following the biofuels boom of the late 2000s. Debate exists about whether the expansion of these crops caused conversion of grasslands and other carbon-rich ecosystems to cropland or instead replaced other crops on existing agricultural land. We tracked crop-specific...

Engineering World Health (EWH) is a national charitable organization whose mission is the "delivery of medical expertise and equipment to underserved nations." Students at the University of Wisconsin-Madison have started a local chapter, EWH-UW, to promote and develop EWH's mission and to provide students the opportunity to gain hands-on interactiv...