Susan E. Crow

Susan E. Crow
University of Hawaiʻi at Mānoa | UH Manoa · Department of Natural Resources and Environmental Management

PhD

About

97
Publications
83,528
Reads
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3,712
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Introduction
In my Soil Ecology and Biogeochemistry research group, we study C dynamics and sequestration, greenhouse gas flux, nutrient and water management in natural and managed (forested or agriculture) ecosystems and how these relate to global change pressures - such as land-use, climate change, and invasive species - sustainable agriculture, and renewable energy production. We pursue mechanistic understanding of ecosystem processes to tackle tough questions relevant to current environmental issues.
Additional affiliations
June 2007 - May 2009
Queen's University Belfast
Position
  • Research Associate
April 2006 - May 2007
Purdue University
Position
  • PostDoc Position
January 2002 - March 2006
Oregon State University
Position
  • PhD Student

Publications

Publications (97)
Article
Full-text available
Tropical regions hold one third of the world’s soil organic carbon, but few experiments have warmed tropical soils in situ. The vulnerability of these soils to climate change-induced losses is uncertain with many hypothesizing these soils would be less sensitive to climate change because already-high temperatures in tropical systems might limit mic...
Article
Converting lignocellulose to bioenergy and biobased products requires targeted breakdown of complex plant polymers that protect structural sugars. To identify lignophenolic compounds that promote enzymatic hydrolysis, the lignophenolic composition of biomass across 12 species and varieties of the Poaceae (grass) family were measured using copper (I...
Preprint
Soils are a promising reservoir to store carbon (C) and mediate greenhouse gas emissions; however, long timescales are required to store amounts of C of relevance to mitigate climate change. Here we conceptually and computationally connect the concepts of permanence (policy) and persistence (biogeosciences) to the amount of warming that is avoided...
Article
Understanding the controls on the amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend on whether C is unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a global synthesis of the relative influence of e...
Preprint
Full-text available
Soil health conceptualized as a measurable ecosystem property provides a powerful tool for monitoring progress in restoration projects or implementation of best management practices to promote sustainable agroecosystems. We surveyed soils collected from a range of land uses (i.e., protected native and non-native forest, managed pasture, unmanaged p...
Article
Full-text available
As the extent of secondary forests continues to expand throughout the tropics, there is a growing need to better understand the ecosystem services, including carbon (C) storage provided by these ecosystems. Despite their spatial extent, there are limited data on how the ecosystem services provided by secondary forest may be enhanced through the res...
Article
Full-text available
Ecosystems play a fundamental role in climate change mitigation by photosynthetically fixing carbon from the atmosphere and storing it for a period of time in organic matter. Although climate impacts of carbon emissions by sources can be quantified by global warming potentials, the appropriate formal metrics to assess climate benefits of carbon rem...
Article
Full-text available
The functions and interactions of individual microbial populations and their genes in agricultural soils amended with biochar remain elusive but are crucial for a deeper understanding of nutrient cycling and carbon (C) sequestration. In this study, we coupled DNA stable isotope probing (SIP) with shotgun metagenomics in order to target the active c...
Article
Full-text available
As part of an integrated energy and climate system, biomass production for bioenergy based on the tropical perennial C4 grass energycane can both offset fossil fuels and store soil carbon (C). We measured energycane yields, root biomass, soil C pools, and soil C stocks in a four‐year field trial and modeled C flow from plants to soils in the surfac...
Article
Full-text available
The magnitude of carbon (C) loss to the atmosphere via microbial decomposition is a function of the amount of C stored in soils, the quality of the organic matter, and physical, chemical, and biological factors that comprise the environment for decomposition. The decomposability of C is commonly assessed by laboratory soil incubation studies that m...
Preprint
Full-text available
Ecosystems play a fundamental role in climate change mitigation by taking up carbon from the atmosphere and storing it for a period of time in organic matter. Although climate impacts of carbon emissions can be quantified by global warming potentials, it is not necessarily clear what are appropriate formal metrics to assess climate benefits of carb...
Article
Full-text available
Radiocarbon is a critical constraint on our estimates of the timescales of soil carbon cycling that can aid in identifying mechanisms of carbon stabilization and destabilization and improve the forecast of soil carbon response to management or environmental change. Despite the wealth of soil radiocarbon data that have been reported over the past 75...
Preprint
Full-text available
Abstract. The magnitude of carbon (C) loss to the atmosphere via microbial decomposition is a function of the amount of C stored in soils, the quality of the organic matter, and physical, chemical and biological factors that comprise the environment for decomposition. The decomposability of C is commonly assessed by laboratory soil incubation studi...
Article
Our ability to reliably use radiocarbon ( ¹⁴ C) dates of mollusk shells to estimate calendar ages may depend on the feeding preference and habitat of a particular species and the geology of the region. Gastropods that feed by scraping are prone to incorporation of carbon from the substrate into their shells as evidenced by studies comparing the rad...
Article
Full-text available
Radiocarbon is a critical constraint on our estimates of the timescales of soil carbon cycling that can aid in identifying mechanisms of carbon stabilization and destabilization, and improve forecast of soil carbon response to management or environmental change. Despite the wealth of soil radiocarbon data that has been reported over the past 75 yea...
Article
Full-text available
The incorporation of biochar into soil is a promising management strategy for sustainable agriculture owing to its potential to sequester carbon and improve soil fertility. Expanding the addition of biochar to large-scale agriculture hinges on its lasting beneficial effects on the microbial community. However, there exists a significant knowledge g...
Article
The presence of large numbers of free-ranging feral cats (Felis catus) has raised concern in terms of both native species predation and potential disease transmission in Hawai'i. A disease of particular concern is toxoplasmosis, caused by Toxoplasma gondii, a zoonotic protozoan parasite. We tested soil samples and cat fecal samples from cat colonie...
Article
Full-text available
Background: The environmental costs of fossil fuel consumption are globally recognized, opening many pathways for the development of regional portfolio solutions for sustainable replacement fuel and energy options. The purpose of this study was to create a baseline carbon (C) budget of a conventionally managed sugarcane (Saccharum officinarum) pro...
Article
Full-text available
Soil organic matter (SOM) turnover increasingly is conceptualized as a tension between accessibility to microorganisms and protection from decomposition via physical and chemical association with minerals in emerging soil biogeochemical theory. Yet, these components are missing from the original mathematical models of belowground carbon dynamics an...
Article
Full-text available
Accurately capturing dynamic soil response to disturbance effects in agroecosystem models remains elusive, thereby limiting projections of climate change mitigation potential. Perennial grasses cultivated in zero-tillage management systems hold promise as sustainable agroecosystems. High-yielding tropical C grasses often have extensive rooting syst...
Presentation
Full-text available
The International Soil Radiocarbon Database (ISRaD) is an open-source, community resource intended to improve constraints on global carbon models and provide a centralized repository for soil fraction data, including incubations and interstitial measurements.
Preprint
Full-text available
The presence of large numbers of free-ranging feral cats (Felis catus) has raised concern in terms of both native species predation and potential disease transmission in Hawai'i. A disease of particular concern is toxoplasmosis, caused by Toxoplasma gondii, a zoonotic protozoan parasite. We tested soil samples and cat fecal samples from cat colonie...
Article
Full-text available
Effective soil management is critical to achieving climate change mitigation in plant-based renewable energy systems, yet limitations exist in our understanding of dynamic belowground responses to the cultivation of energy crops. To better understand the belowground dynamics following cultivation of a grassland in a high-yielding tropical perennial...
Article
Full-text available
Improved quantification of the factors controlling soil organic matter (SOM) stabilization at continental to global scales is needed to inform projections of the largest actively cycling terrestrial carbon pool on Earth, and its response to environmental change. Biogeochemical models rely almost exclusively on clay content to modify rates of SOM tu...
Chapter
Biochar is organic matter that has undergone combustion under low to no oxygen conditions (i.e., pyrolysis) resulting in a recalcitrant, high carbon material specifically for use as a soil amendment. Recently, fervent interest in the production of biochar to address issues of fertility, water holding capacity, remediation, climate change mitigation...
Article
Soil organic matter (SOM) anchors global terrestrial productivity and food and fiber supply. SOM retains water and soil nutrients and stores more global carbon than do plants and the atmosphere combined. SOM is also decomposed by microbes, returning CO2, a greenhouse gas, to the atmosphere. Unfortunately, soil carbon stocks have been widely lost or...
Article
Full-text available
Soil organic matter (SOM) supports the Earth's ability to sustain terrestrial ecosystems, provide food and fiber, and retains the largest pool of actively cycling carbon. Over 75% of the soil organic carbon (SOC) in the top meter of soil is directly affected by human land use. Large land areas have lost SOC as a result of land use practices, yet th...
Article
Although biomass sorghum [Sorghum bicolor (L.) Moench] has been identified as a high yielding bioenergy feedstock crop on the continental USA, there is however lack of conclusive data on its performance in Hawaii (HI). The objectives of this study were to (i) determine the adaptability and productivity of two biomass sorghum hybrids, and (ii) ident...
Article
Full-text available
Biomass is a promising renewable energy option that provides a more environmentally sustainable alternative to fossil resources by reducing the net flux of greenhouse gasses to the atmosphere. Yet, allometric models that allow the prediction of aboveground biomass (AGB), biomass carbon (C) stock non-destructively have not yet been developed for tro...
Chapter
Full-text available
The natural capacity of the terrestrial landscape to capture and store carbon from the atmosphere can be used in cultivated systems to maximize the climate change mitigation potential of agricultural regions. A combination of inherent soil carbon storage potential, conservation management, and rhizosphere inputs should be considered when making lan...
Article
Full-text available
Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we co...
Article
Full-text available
Perennial grasses can sequester soil organic carbon (SOC) in sustainably managed biofuel systems, directly mitigating atmospheric CO2 concentrations while simultaneously generating biomass for renewable energy. The objective of this study was to quantify SOC accumulation and identify the primary drivers of belowground C dynamics in a zero-tillage p...
Article
Full-text available
This research was conducted to determine the potential for the use of Conservation Agriculture Production Systems (CAPS) in the hill region of Nepal, an area highly prone to food insecurity and soil losses. Conservation agriculture (CA) includes the practices of tillage reduction, soil cover maintenance, and optimal crop rotation. Farming in Nepal...
Article
Full-text available
Mitigation of climate change via increased plant productivity and soil carbon (C) sequestration during land use change can be a powerful driver of the net greenhouse gas emissions of a sustainable production system. Yet the net climate change mitigation of managed forests is affected by both tradeoffs between C sequestration and non-renewable C emi...
Article
Full-text available
The renewed interest in the use of sugarcane (Saccharin officinarum L.) for biofuel could provide a viable market for potential Hawaiian sugarcane feedstock producers. In Hawaii, sugarcane is grown as an irrigated 2-yr cycle crop. there is however little information on crop parameter attributes of 2-yr cycle sugarcane. Th is field study on Maui, Ha...
Chapter
Full-text available
This book focuses on the latest research in conservation agriculture (CA), with an emphasis on the applicability of results worldwide. Using South Asia as a case study, it examines the history and current state of CA regionally and globally, and explores the long-term impacts the adoption of CA practices has on the livelihoods, agricultural product...
Chapter
Full-text available
This book focuses on the latest research in conservation agriculture (CA), with an emphasis on the applicability of results worldwide. Using South Asia as a case study, it examines the history and current state of CA regionally and globally, and explores the long-term impacts the adoption of CA practices has on the livelihoods, agricultural product...
Article
Full-text available
Volcanic ash-derived soils are important globally for their C sequestration potential and because they are at risk of compaction and degradation due to land use change. Poorly or non-crystalline minerals impart enormous capacity for soils to store and stabilize C, but also unusual chemical and physical properties that make quantifying meaningful so...
Conference Paper
Full-text available
Conservation agriculture (CA) systems composed of intercropping and strip tillage practices were evaluated on marginalized maize-based farming system in hill region of Nepal. On-farm experimental trials were conducted on the field of 25 smallholder farmers in three villages of central mid-hill region. Results indicated that although CA systems did...
Article
Full-text available
The universally observed exponential increase in soil-surface CO2 efflux ('soil respiration'; F S) with increasing temperature has led to speculation that global warming will accelerate soil-organic-carbon (SOC) decomposition 1 , reduce SOC storage, and drive a positive feedback to future warming 2 . However, interpreting temperature–F S relationsh...
Article
Full-text available
The terrestrial biosphere sequesters up to a third of annual anthropogenic carbon dioxide emis-sions, offsetting a substantial portion of greenhouse gas forcing of the climate system. Although a number of factors are responsible for this terrestrial carbon sink, atmospheric nitrogen deposition contributes by enhancing tree productivity and promotin...
Article
Full-text available
Departing from the traditional agricultural model of input-heavy, intensive agriculture via the use of agrochemicals and irrigated water, many international development projects have started to promote conservation agriculture in developing countries. However, relying solely on technical expertise, largely generated outside the rural communities in...
Article
A predator-proof fence was built at Kaena Point Natural Area Reserve, Hawaii in 2010 as part of an ecosystem restoration project. All non-native mammalian predators were removed and are now excluded. Non-native plants are being removed and native species are being outplanted. We monitored abundance and reproduction of Puffinus pacificus (wedge-tail...
Chapter
Chemical functions – Humus is finely divided stable organic matter. Due to the large exposed surface area, humus contributes 30-70% of the cation exchange sites that adsorb plant nutrients that are eventually taken up by plants. Humus chelates micronutrients (usually iron, zinc, copper, or manganese) into soluble compounds, hence increasing their g...
Article
Full-text available
Partially decomposed plant and animal remains have been accumulating in organic soils (i.e. >40% C content) for millennia, making them the largest terrestrial carbon store. There is growing concern that, in a warming world, soil biotic processing will accelerate and release greenhouse gases that further exacerbate climate change. However, the magni...