KDF Search Results

Link to the website with documentation and download instructions for the PNNL Global Change Assessment Model (GCAM), a community model or long-term, global energy, agriculture, land use, and emissions. BioEnergy production, transformation, and use is an integral part of GCAM modeling and scenarios.

http://jgcri.github.io/gcam-doc/

This paper analyzes the rural Chinese biomass supply system and models supply chain operations according to U.S. concepts of logistical unit operations: harvest and collection, storage, transportation, preprocessing, and handling and queuing. In this paper, we quantify the logistics cost of corn stover and sweet sorghum in China under different scenarios. We analyze three scenarios of corn stover logistics from northeast China and three scenarios of sweet sorghum stalks logistics from Inner Mongolia in China.

Harvesting of corn stover (plant residues) for cellulosic ethanol production must be balanced with the requirement for returning plant residues to agricultural fields to maintain soil structure, fertility, crop protection, and other ecosystem services. High rates of corn stover removal can be associated with decreased soil organic matter (SOM) quantity and quality and increased highly erodible soil aggregate fractions.

In-field measurements of direct soil greenhouse gas (GHG) emissions provide critical data for quantifying the net energy efficiency and economic feasibility of crop residue-based bioenergy production systems. A major challenge to such assessments has been the paucity of field studies addressing the effects of crop residue removal and associated best practices for soil management (i.e., conservation tillage) on soil emissions of carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4).

Harvesting crop residue needs to be managed to protect agroecosystem health and productivity. DAYCENT, a process-based modeling tool, may be suited to accommodate region-specific factors and provide regional predictions for a broad array of agroecosystem impacts associated with corn stover harvest. Grain yield, soil C, and N2O emission data collected at Corn Stover Regional Partnership experimental sites were used to test DAYCENT performance modeling the impacts of corn stover removal.

Corn stover is targeted as a potential non-food bioenergy feedstock, especially in the Midwest United States.  Three parallel experiments on adjacent fields, one is managed without tillage since 1995, a second experiment is managed without tillage since 2005, and the third is managed with chisel plowing since 2005.  The residue removal treatments are the same in all experiments, with 0, 50%, 75% and 100% of the rows from plots in the corn phase of the rotation harvested. In 2008, the 75% stover removal was changed to cob removal.

Indicators are needed to assess environmental sustainability of bioenergy systems. Effective indicators
will help in the quantification of benefits and costs of bioenergy options and resource uses. We identify
19 measurable indicators for soil quality, water quality and quantity, greenhouse gases, biodiversity, air
quality, and productivity, building on existing knowledge and on national and international programs
that are seeking ways to assess sustainable bioenergy. Together, this suite of indicators is hypothesized

Adding bioenergy to the U.S. energy portfolio requires long‐term profitability for bioenergy producers and
long‐term protection of affected ecosystems. In this study, we present steps along the path toward evaluating both sides of
the sustainability equation (production and environmental) for switchgrass (Panicum virgatum) using the Soil and Water
Assessment Tool (SWAT). We modeled production of switchgrass and river flow using SWAT for current landscapes at a

Relationships between people and their environment are largely defined by land use. Space and soil are needed for native plants and wildlife, as well as for crops used for food, feed, fiber, wood products and biofuel (liquid fuel derived from plant material). People also use land for homes, schools, jobs, transportation, mining and recreation. Social and economic forces influence the allocation of land to various uses.

A broad-scale perspective on the nexus between climate change, land use, and energy requires consideration of interactions that were often omitted from climate change studies. While prior analyses have considered how climate change affects land use and vice versa (Dale 1997), there is growing awareness of the need to include energy within the analytical framework. A broad-scale perspective entails examining patterns and process at divers spatial and temporal resolutions.

The establishment of bioenergy crops will affect ecological processes and their interactions and thus has an influence on ecosystem services provided by the lands on which these crops are grown. The regional-scale effects of bioenergy choices on ecosystem services need special attention because they often have been neglected yet can affect the ecological, social, and economic aspects of sustainability.

Developing scientific criteria and indicators should play a critical role in charting a sustainable path for the rapidly developing biofuel industry. The challenge ahead in developing such criteria and indicators is to address the limitations on data and modeling.

The U.S. Department of Energy Biomass Program sponsored the Land-Use Change and Bioenergy workshop in Vonore, Tennessee, from May 11 to May 14, 2009. More than 50 experts from around the world gathered to review the state of the science, identify opportunities for collaboration, and prioritize next steps for the research and data needed to address key issues regarding the land-use effects of bioenergy policies. A key outcome of the workshop was the
identification of research areas that may improve our understanding of land-use change in a bioenergy context.

Despite recent claims to the contrary, plant-based fuels developed in economically and environmentally sensible ways can contribute significantly to the nation’s— indeed, the world’s—energy security while providing a host of benefits for many people worldwide.

As the US begins to integrate biomass crops and residues into its mix of energy feedstocks, tools are needed to measure the long-term sustainability of these feedstocks. Two aspects of sustainability are long-term potential for profitably producing energy and protection of ecosystems influenced by energy-related activities. The Soil and Water Assessment Tool (SWAT) is an important model used in our efforts to quantify both aspects. To quantify potential feedstock production, we used SWAT to estimate switchgrass yields at a national scale.

In response to concerns about oil dependency and the contributions of fossil fuel use to climatic change, the U.S. Department of Energy has begun a research initiative to make 20% of motor fuels biofuel based in 10 years, and make 30% of fuels bio-based by 2030. Fundamental to this objective is developing an understanding of feedstock dynamics of crops suitable for cellulosic ethanol production. This report focuses on switchgrass, reviewing the existing literature from field trials across the United States, and compiling it for the first time into a single database.

The harvest of corn stover or herbaceous crops as feedstocks for bioenergy purposes has been shown to have significant benefits from energy and climate change perspectives. There is a potential, however, to adversely impact water and soil quality, especially in Midwestern states where the biomass feedstock production would predominantly occur.

IN THEIR REPORTS IN THE 29 FEBRUARY ISSUE (“LAND CLEARING AND THE BIOFUEL CARBON debt,” J. Fargione et al., p. 1235, and “Use of U.S. croplands for biofuels increases greenhouse gases through emissions from land-use change,” T. Searchinger et al., p. 1238), the authors do not provide adequate support for their claim that biofuels cause high emissions due to land-use change. The conclusions of both papers depend on the misleading premise that biofuel production causes forests and grasslands to be converted to agriculture.

National interests in greater energy independence, concurrent with favorable market forces, have driven increased production of corn-based ethanol in the United States and research into the next generation of biofuels. The trend is changing the national agricultural landscape and has raised concerns about potential impacts on the nation?s water resources. This report examines some of the key issues and identifies opportunities for shaping policies that help to protect water resources.