Poortinga A.,Winrock International |
Bastiaanssen W.,Technical University of Delft |
Simons G.,Technical University of Delft |
Saah D.,Spatial Informatics Group |
And 5 more authors.
Remote Sensing | Year: 2017
Due to increasing pressures on water resources, there is a need to monitor regional water resource availability in a spatially and temporally explicit manner. However, for many parts of the world, there is insufficient data to quantify stream flow or ground water infiltration rates. We present the results of a pixel-based water balance formulation to partition rainfall into evapotranspiration, surface water runoff and potential ground water infiltration. The method leverages remote sensing derived estimates of precipitation, evapotranspiration, soil moisture, Leaf Area Index, and a single F coefficient to distinguish between runoff and storage changes. The study produced significant correlations between the remote sensing method and field based measurements of river flow in two Vietnamese river basins. For the Ca basin, we found R2 values ranging from 0.88-0.97 and Nash-Sutcliffe efficiency (NSE) values varying between 0.44-0.88. The R2 for the Red River varied between 0.87-0.93 and NSE values between 0.61 and 0.79. Based on these findings, we conclude that the method allows for a fast and cost-effective way to map water resource availability in basins with no gauges or monitoring infrastructure, without the need for application of sophisticated hydrological models or resource-intensive data. © 2017, by the authors; licensee MDPI, Basel, Switzerland.
Tantipisanuh N.,King Mongkut's University of Technology Thonburi |
Savini T.,King Mongkut's University of Technology Thonburi |
Cutter P.,Spatial Informatics Group |
Gale G.A.,King Mongkut's University of Technology Thonburi
Biological Conservation | Year: 2016
Historically, designation of protected areas was biased toward specific habitats, resulting in insufficient representation of other habitats and their associated species. We identified gaps in current protected areas of the Indo-Burma Hotspot, proposed additional areas that could be included in PA systems of this hotspot to increase overall representation, and identified high priority areas for inclusion. Land cover types and threatened terrestrial vertebrate species were used as surrogates of biodiversity, and their representations were assessed using a gap analysis. Areas to be added to improve the hotspot's protected area systems were identified using Marxan software. High priority areas were selected based on irreplaceability and vulnerability. The representation of biodiversity in this hotspot is currently skewed in terms of habitats and species. There is a bias toward mammals in terms of representation (75%), while amphibians are not well represented (27%). With our optimal scenario, 21% of the hotspot's entire land area would need to be included in protected area systems, compared to 16% currently, to achieve more complete representation targets. Myanmar had the most additional areas required. Two-thirds of the additional areas needed to represent conservation features were <10 km2. Several suggested areas were located along borders between multiple countries. Representation within protected areas in the Indo-Burma Hotspot can be significantly improved by focusing on maintaining and restoring linkages between smaller patches to create and sustain larger protected area networks. As part of this enhancement, trans-boundary collaboration among countries within the hotspot will be particularly important. © 2016 Elsevier Ltd.
Gonzalez P.,National Park Service |
Battles J.J.,University of California at Berkeley |
Collins B.M.,U.S. Department of Agriculture |
Robards T.,Spatial Informatics Group |
And 2 more authors.
Forest Ecology and Management | Year: 2015
The balance between ecosystem emissions of carbon to the atmosphere and removals from the atmosphere indicates whether ecosystems are exacerbating or reducing climate change. Forest ecosystems in the State of California, USA, contain carbon that reaches the highest densities (mass per unit area) in the world, but it has been unresolved whether California ecosystems currently comprise a net sink or source of carbon. The California Global Warming Solutions Act of 2006 established greenhouse gas reduction targets for fossil fuel-burning sectors and ecosystems, underscoring the importance of tracking ecosystem carbon. Here, we conduct statewide spatial inventories of the aboveground live carbon stocks of forests and other terrestrial ecosystems of California, excluding agricultural and urban areas. We analyzed biomass data from field measurements of the Forest Inventory and Analysis program, published biomass information and remote sensing data on non-forest vegetation, and spatial distributions of vegetation types, height, and fractional cover derived by the Landfire program from Landsat remote sensing at 30m spatial resolution. We conducted Monte Carlo analyses of the uncertainty of carbon stock change estimates from errors in tree biomass estimates, remote sensing, and estimates of the carbon fraction of biomass. The carbon stock in aboveground biomass was 850±230 Tg (mean±95% confidence interval) in 2010. We found a net aboveground live carbon stock change of -69±15 Tg from 2001 to 2010, a rate of change of -0.8±0.2%y-1. Due to slow decay of some dead wood, all of the live carbon stock change does not immediately generate emissions. Wildfires on 6% of the state analysis area produced two-thirds of the live carbon stock loss. This suggests that increased tree densities from a century of fire suppression have allowed the accumulation of fuel for carbon losses in recent wildfires. Remote sensing errors in vegetation classification accounted for most of the uncertainty in the carbon stock change estimates. Improvements are also needed to track spatial patterns of growth and dead wood. Our results establish the beginning of a time series for the state greenhouse gas inventory and provide information on the role of forest conservation and management in California in mitigating global climate change. © 2015 .
Gunn J.S.,Initiative Capital |
Saah D.S.,Spatial Informatics Group |
Hagan J.M.,Manomet Center for Conservation science
Journal of Sustainable Forestry | Year: 2013
Policies based on assumed carbon neutrality fail to address the timing and magnitude of the net greenhouse gas (GHG) changes from using wood for energy. We present a "debt-then-dividend" framework for evaluating the temporal GHG impacts of burning wood for energy. We also present a case study conducted in Massachusetts, USA to demonstrate the framework. Four key inputs are required to calculate the specific shape of the debt-then-dividend curve for a given region or individual biomass facility. First, the biomass feedstock source: the GHG implications of feedstocks differ depending on what would have happened to the material in the absence of biomass energy generation. Second, the form of energy generated: energy technologies have different generation efficiencies and thus different life cycle GHG emissions profiles. Third, the fossil fuel displaced: coal, oil, and natural gas each have different emissions per unit of energy produced. Fourth, the management of the forest: forest management decisions affect recovery rates of carbon from the atmosphere. This framework has broad application for informing the development of renewable energy and climate policies. Most importantly, this debt-then-dividend framework explicitly recognizes that GHG benefits of wood biomass energy will be specific to the forest and technology context of the region or biomass energy projects. © 2013 Copyright Taylor and Francis Group, LLC.
Panek J.,University of California at Berkeley |
Saah D.,Spatial Informatics Group |
Esperanza A.,Sequoia and Kings Canyon National Parks |
Bytnerowicz A.,U.S. Department of Agriculture |
And 2 more authors.
Environmental Pollution | Year: 2013
Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more vulnerable to other agents of mortality, including insects, pathogens, climate change, and ultimately fire. Here we analyze three years of passive ozone monitor data from the southern Sierra Nevada and interpolate landscape-scale spatial and temporal patterns during the summer-through-fall high ozone concentration period. Segmentation analysis revealed three types of ozone exposure sub-regions: high, low, and variable. Consistently high ozone exposure regions are expected to be most vulnerable to forest mortality. One high exposure sub-region has been documented elsewhere as being further vulnerable to increased drought and fire potential. Identifying such hot-spots of forest vulnerability has utility for prioritizing management. © 2013 Elsevier Ltd. All rights reserved.
Cheng A.S.,Colorado State University |
Gutierrez R.J.,University of Minnesota |
Cashen S.,University of Minnesota |
Becker D.R.,University of Minnesota |
And 7 more authors.
Journal of Forestry | Year: 2016
In 1993, a group of national forest stakeholders, the Quincy Library Group, crafted a proposal that intended to reduce wildfire risk, protect the California spotted owl (Strix occidentalis occidentalis), restore watersheds, and enhance community stability by ensuring a predictable supply of timber for area sawmills and biomass for energy plants. The Herger-Feinstein Quincy Library Group Forest Recovery Act of 1998 codified this proposal, directing the USDA Forest Service to conduct forest treatments on 40, 000–60, 000 acres per year by creating defensible fuel profile zones and logging by group-and individual tree-selection methods. The law also designated an Independent Science Panel to review monitoring studies, administrative studies, and research to assess efficacy of the implementation and achievement of goals. Although several goals were achieved, implementation fell short of treatment and volume goals, and evidence was lacking to make conclusive judgments about environmental impacts. Shortcomings were due to differing interpretations of the Act’s prescriptive intent, changes in management direction, compounding economic factors, appeals and litigation, variation in site-specific forest conditions, and variation in approaches among national forests and districts. Most notable was a lack of monitoring of the treatment effects on California spotted owl populations and other environmental concerns. These findings suggest that attempts to legislate prescriptive, collaboratively developed proposals may not account for the complex biophysical, management, social, and economic contexts within which national forest management occurs. These findings also suggest that current national forest policies and directives promoting collaboration should also be accompanied by a commitment to monitoring and adaptive management. © 2015 Society of American Foresters.
Kerchner C.D.,University of Vermont |
Kerchner C.D.,Spatial Informatics Group |
Keeton W.S.,University of Vermont |
Keeton W.S.,Spatial Informatics Group
Forest Policy and Economics | Year: 2015
Carbon markets have the potential to reward landowners for improved forest management and forest conservation. To date, the Over the Counter (OTC) voluntary market represents the greatest opportunity for forest landowners to participate in carbon transactions. However, lack of a consistent carbon price signal and sporadic demand coupled by high transaction costs has prevented widespread participation from family forest landowners. Adoption of a U.S. based cap-and-trade program reduces price risk and may provide incentives for sustainable forest management across large areas. Yet few studies have examined the supply side of carbon offsets and factors affecting project financial viability. To address this gap, we assessed how (1) property characteristics (i.e. stocking level, forest type, size etc.); (2) silvicultural treatments; and (3) protocol and legislative requirements affect the financial viability of compliance forest offset projects, focusing on California's Air Resource Board (ARB) program due to its significance as the world's second largest carbon market. We used forest inventory data from 25 properties in the northeastern United States to examine the viability of the sites as ARB offset projects. We utilized the U.S. Forest Service Forest Vegetation Simulator for our growth and yield simulations. To examine the factors that influence project viability, we used a classification and regression tree analysis performed in S-Plus software. Results indicate C stocking and property size are the most important property characteristics driving return on investment. However, protocol requirements and legislative assumptions impacting long-term monitoring costs are also important factors. While reduced price risk in a compliance carbon market has the potential to improve forest management in North America; high initial project development costs, long-term monitoring obligations, and legislative uncertainty are significant barriers that will limit family forest landowner market participation. The model developed here can be used by U.S. landowners to assess the financial viability of their property as a compliance offset project and can be utilized by policymakers to develop cost-effective climate change policy. © 2014 Elsevier B.V.
Buchholz T.,Spatial Informatics Group LLC |
Buchholz T.,University of Vermont |
Hurteau M.D.,Pennsylvania State University |
Gunn J.,Spatial Informatics Group |
And 2 more authors.
GCB Bioenergy | Year: 2016
The potential greenhouse gas benefits of displacing fossil energy with biofuels are driving policy development in the absence of complete information. The potential carbon neutrality of forest biomass is a source of considerable scientific debate because of the complexity of dynamic forest ecosystems, varied feedstock types, and multiple energy production pathways. The lack of scientific consensus leaves decision makers struggling with contradicting technical advice. Analyzing previously published studies, our goal was to identify and prioritize those attributes of bioenergy greenhouse gas (GHG) emissions analysis that are most influential on length of carbon payback period. We investigated outcomes of 59 previously published forest biomass greenhouse gas emissions research studies published between 1991 and 2014. We identified attributes for each study and classified study cases by attributes. Using classification and regression tree analysis, we identified those attributes that are strong predictors of carbon payback period (e.g. the time required by the forest to recover through sequestration the carbon dioxide from biomass combusted for energy). The inclusion of wildfire dynamics proved to be the most influential in determining carbon payback period length compared to other factors such as feedstock type, baseline choice, and the incorporation of leakage calculations. Additionally, we demonstrate that evaluation criteria consistency is required to facilitate equitable comparison between projects. For carbon payback period calculations to provide operational insights to decision makers, future research should focus on creating common accounting principles for the most influential factors including temporal scale, natural disturbances, system boundaries, GHG emission metrics, and baselines. © 2016 John Wiley & Sons Ltd.