Spatial-temporal Modeling of Soil Organic Carbon Across a Subtropical Region PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Spatial-temporal Modeling of Soil Organic Carbon Across a Subtropical Region PDF full book. Access full book title Spatial-temporal Modeling of Soil Organic Carbon Across a Subtropical Region by Christopher Wade Ross. Download full books in PDF and EPUB format.
Author: Christopher Wade Ross
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Significant differences were found to exist among various LC/LU's in regards to mean SOC stocks (kg m−2, 0-20cm), with the highest amounts found in Cypress Swamp (9.7), Hardwood Swamp (9.6) and Mixed Wetland Forest (7.8). Additionally, significant SOC stock differences among various soil types exist as well, with the highest mean stocks (kg m−2, 0-20cm) belonging to Saprists (12), Aquolls (9.8) and Aquepts (9.4). Geostatistical (kriging) models developed for the study area show approximately 102 - 108 Tg SOC (kg C m−2) are held within the upper 20cm of soils representing historical conditions (DS1) and 211 - 320 Tg SOC (kg C m−2) are held within the upper 20cm of soils representing current conditions (DS2), which suggests the soils in the study area have been a net sink for C during the last 40 years. Highest SOC stock sequestration rates were observed in Hardwood/Cypress Swamp (51 g C m−2 yr−1) and the lowest observed in Xeric Upland Forest ( -129 g C m−2 yr−1). Additionally, site remaining in Row/field Crop lost SOC ( -2g C m−2 yr−1) on average. Interestingly, three out of four classes switching to Urban resulted in net gains of SOC stocks. Geostatistical models improved the knowledge of the spatial distribution and variability of SOC in the study area with implications for SOC cycling, land management, environmental conservation and policy decisions.
Author: Christopher Wade Ross
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Significant differences were found to exist among various LC/LU's in regards to mean SOC stocks (kg m−2, 0-20cm), with the highest amounts found in Cypress Swamp (9.7), Hardwood Swamp (9.6) and Mixed Wetland Forest (7.8). Additionally, significant SOC stock differences among various soil types exist as well, with the highest mean stocks (kg m−2, 0-20cm) belonging to Saprists (12), Aquolls (9.8) and Aquepts (9.4). Geostatistical (kriging) models developed for the study area show approximately 102 - 108 Tg SOC (kg C m−2) are held within the upper 20cm of soils representing historical conditions (DS1) and 211 - 320 Tg SOC (kg C m−2) are held within the upper 20cm of soils representing current conditions (DS2), which suggests the soils in the study area have been a net sink for C during the last 40 years. Highest SOC stock sequestration rates were observed in Hardwood/Cypress Swamp (51 g C m−2 yr−1) and the lowest observed in Xeric Upland Forest ( -129 g C m−2 yr−1). Additionally, site remaining in Row/field Crop lost SOC ( -2g C m−2 yr−1) on average. Interestingly, three out of four classes switching to Urban resulted in net gains of SOC stocks. Geostatistical models improved the knowledge of the spatial distribution and variability of SOC in the study area with implications for SOC cycling, land management, environmental conservation and policy decisions.
Author: Kristofer Dee Johnson
Publisher:
ISBN:
Category :
Languages : en
Pages : 356
Get Book Here
Book Description
Forest soils contribute to a significant portion of the world's carbon flux due to both natural and anthropogenic changes. In terms of human management of carbon pools, forest soil organic matter (SOM) is important because it potentially stores carbon more permanently than living vegetation. Yet, this potential is poorly understood or managed for because of the difficulty in measuring changes in SOM pools over time and space. Modeling combined with intensive field sampling can help overcome these limitations because it extracts from empirically observed relationships to account for the components of SOM formation (topography, time, parent material, organisms and climate [fns2] ). This study utilizes intensive field data, statistical models and process-based ecosystem models to investigate the spatial distribution and dynamics of soil organic carbon dynamics in two contrasting ecosystems--the northern hardwood forest in the Green Mountains, VT and the tabonuco forest in the Luquillo Experimental Forest, PR. In both forests landscape position emerged as the dominate factor in explaining SOM distribution. In Vermont, additional variation was explained by aspect and slope and in Puerto Rico additional variation was explained by landscape factors interrelated to soil drainage. Process-based modeling proved to be a useful management and experimental tool in cases were empirical approaches were impractical for both forests. In Vermont, three ecosystem models demonstrated a substantial reduction of soil organic carbon and harvestable biomass due to the removal of woody carbon by logging after 240 years of rotations. In Puerto Rico, the Century model showed that changes in litter quality and quantity were not likely responsible in explaining landscape level SOM differences. Overall, well drained soils located in colder climates stored the highest SOM whereas poorly drained and highly disturbed soils in steep humid climates stored the lowest SOM. This research demonstrates that although SOM amounts are highly variable over many spatial and temporal scales, intuitive relationships are borne out with modeling tools and by careful investigation of the five soil forming factors. Results also raise questions about how these ecosystems and their SOM pools may change in response to changing climate conditions of the future.
Author: Xiong Xiong
Publisher:
ISBN:
Category :
Languages : en
Pages : 160
Get Book Here
Book Description
Results showed that five sites had different spatial structure - Hardwood Hammock and Forest and Improved Pasture demonstrated both large variation at both coarse scale (67 and> 200 m) and very fine scale (2 m). Sandhill, Pineland and Dry Prairie were dominated by variation at very fine scales (2 and 7 m). All the five sites showed large variability at very fine scales, indicating the close coupling of SOC variation to structure and composition of vegetation. Lastly, the SOC change coupled with LULC and climatic factors over the past four decades was studied. Significant SOC accumulation was observed between 1965-1996 and 2008-2009 and concomitant LULC and LULC change significantly affected SOC change, less so climatic factors. The study improved the knowledge of the spatial and temporal variation of SOC in the complex soil-landscape continuum of Florida with implications for carbon cycling and sequestration, land resource management, and ecosystem service assessment.
Author: Werner L. Kutsch
Publisher: Cambridge University Press
ISBN: 1139483161
Category : Technology & Engineering
Languages : en
Pages : 301
Get Book Here
Book Description
Carbon stored in soils represents the largest terrestrial carbon pool and factors affecting this will be vital in the understanding of future atmospheric CO2 concentrations. This book provides an integrated view on measuring and modeling soil carbon dynamics. Based on a broad range of in-depth contributions by leading scientists it gives an overview of current research concepts, developments and outlooks and introduces cutting-edge methodologies, ranging from questions of appropriate measurement design to the potential application of stable isotopes and molecular tools. It includes a standardised soil CO2 efflux protocol, aimed at data consistency and inter-site comparability and thus underpins a regional and global understanding of soil carbon dynamics. This book provides an important reference work for students and scientists interested in many aspects of soil ecology and biogeochemical cycles, policy makers, carbon traders and others concerned with the global carbon cycle.
Author: Alfred E. Hartemink
Publisher: Springer Science & Business Media
ISBN: 3319040847
Category : Nature
Languages : en
Pages : 503
Get Book Here
Book Description
Few topics cut across the soil science discipline wider than research on soil carbon. This book contains 48 chapters that focus on novel and exciting aspects of soil carbon research from all over the world. It includes review papers by global leaders in soil carbon research, and the book ends with a list and discussion of global soil carbon research priorities. Chapters are loosely grouped in four sections: § Soil carbon in space and time § Soil carbon properties and processes § Soil use and carbon management § Soil carbon and the environment A wide variety of topics is included: soil carbon modelling, measurement, monitoring, microbial dynamics, soil carbon management and 12 chapters focus on national or regional soil carbon stock assessments. The book provides up-to-date information for researchers interested in soil carbon in relation to climate change and to researchers that are interested in soil carbon for the maintenance of soil quality and fertility. Papers in this book were presented at the IUSS Global Soil C Conference that was held at the University of Wisconsin-Madison, USA.
Author: Andreas Schulte
Publisher: Springer Science & Business Media
ISBN: 3662036495
Category : Science
Languages : en
Pages : 220
Get Book Here
Book Description
An understanding of the characteristics and the ecology of soils, particularly those of forest ecosystems in the humid tropics, is central to the development of sustainable forest management systems. The present book examines the contribution that forest soil science and forest ecology can make to sustainable land use in the humid tropics. Four main issues are addressed: characteristics and classification of forest soils, chemical and hydrological changes after forest utilization, soil fertility management in forest plantations and agroforestry systems as well as ecosystem studies from the dipterocarp forest region of Southeast Asia. Additionally, case studies include work from Guyana, Costa Rica, the Philippines, Malaysia, Australia and Nigeria.
Author: Tara Ippolito
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
The management of Soil Organic Carbon (SOC) is a critical component of both nature-based solutions for climate change mitigation and global food security. Agriculture has contributed substantially to a reduction in global SOC through cultivation, thus there has been renewed focus on management practices which minimize SOC losses and increase SOC gain as pathways towards maintaining healthy soils and reducing net greenhouse gas emissions. Mechanistic models are frequently used to aid in identifying these pathways due to their scalability and cost-effectiveness. Yet, they are often computationally costly and rely on input data that are often only available at coarse spatial resolutions. Herein, we build statistical meta-models of a multifactorial crop model in order to both (a) obtain a simplified model response and (b) explore the biophysical determinants of SOC responses to management and the geospatial heterogeneity of SOC dynamics across Europe. Using 512 million unique, spatially-explicit crop growth simulations from the gridded Environmental Policy Integrated Climate-based Gridded Agricultural Model (EPIC-IIASA GAM), we build multiple polynomial regression ensemble meta-models for unique combinations of climate and soil across Europe in order to predict SOC responses to varying management intensities. We find that our biophysically-determined meta-models are highly accurate (R2 = .97) representations of the full mechanistic model and can be used in lieu of the full EPIC-IIASA GAM model for the estimation of SOC responses to cropland management. Model stratification by means of climate and soil clustering improved the performance of the meta-models compared to the full EU-scale model. In regional and local validations of the meta-model predictions, we find that the meta-models accurately capture broad SOC dynamics such as the linear nature of SOC responses to residue application, yet they often underestimate the magnitude of SOC responses to management. Furthermore, we find notable differences between the results from the biophysically-specific models throughout Europe, which point to spatially-distinct SOC responses to management choices such as nitrogen fertilizer application rates and residue retention that illustrate the potential for these models to be used for future management applications. While more accurate input data, calibration, and validation will be needed to accurately predict SOC change, we demonstrate the use of our meta-models for biophysical cluster and field study scale analyses of broad SOC dynamics with basically zero fine-tuning of the models needed. This work provides a framework for simplifying large-scale agricultural models and identifies the opportunities for using these meta-models for assessing SOC responses to management at a variety of scales.
Author: Mario Guevara
Publisher:
ISBN:
Category :
Languages : en
Pages : 252
Get Book Here
Book Description
The largest carbon pool in terrestrial ecosystems is contained in soils and it plays a key role regulating hydrological processes, such as the spatial variability of soil moisture dynamics. Specifically, soil moisture and soil organic carbon are variables directly linked to ecosystem services such as food production and water storage. However, there are important knowledge gaps in the spatial representation (e.g., maps) of soil moisture and soil organic information from the country specific to the global scales. There is a pressing need to update the spatial detail of soil moisture estimates and the accuracy of digital soil carbon maps for improved land management, improved Earth system modeling and improved strategies (i.e., public policy) to combat land degradation. From the country specific to the global scale, the overreaching goal of this PhD research is to develop a reproducible digital soil mapping framework to increase the statistical accuracy of spatially continuous information on soil moisture and soil organic carbon across different scales of data availability (e.g., country-specific, regional, global). Chapter 1 provides a general introduction. Chapters 2 and 3 are focused on up-scaling soil organic carbon from the country-specific scale to the continental scale. Chapter 2 provides a country-specific and multi-modeling approach for soil organic carbon mapping across Latin America, where I identify key predictors and conclude that there is no best modeling method in a quantifiable basis across all the analyzed countries. In Chapter 3, I compare and test different methods and combinations of prediction factors to model the variability of soil organic carbon across Mexico and conterminous United States (CONUS). I describe soil organic carbon stocks across different land covers across the region, quantify the model uncertainty and discuss estimates derived from previous studies. Chapters 4 and 5 are devoted to improving the statistical detail and accuracy of satellite soil moisture from the country to the global scale. Chapter 4 describes how the machine learning fusion of satellite soil moisture with Geomorphometry increase the statistical accuracy and spatial detail of current soil moisture estimates across CONUS. Chapter 5 extends the previous chapter to the global scale and identifies global soil moisture trends. I provide a novel (gap-free) soil moisture global estimate that could be potentially used to predict the global feedback between primary productivity and long-term soil moisture trends. Chapters 4 and 5 reveal evidence of soil moisture decline across large areas of the world. Finally, chapter 6 summarizes the main findings of this research, the key conclusions, emergent challenges and future steps. The results of this research were useful to generate benchmarks against which to assess the impact of climate and land cover changes on soil organic carbon stocks and soil moisture trends. This research provides a framework (including high quality data and novel methodologies) to generate environmentally relevant science that can be used for the formulation of public policy around soil and water conservation efforts.
Author:
Publisher:
ISBN: 9789462575899
Category :
Languages : en
Pages : 214
Get Book Here
Book Description
Author: Erik Ray Venteris
Publisher:
ISBN:
Category :
Languages : en
Pages : 444
Get Book Here
Book Description
