Physical Sciences and Mathematics Commons^™

Alternative Land Use Options For Philippine Grasslands: A Bioeconomic Modeling Approach Using The Wanulcas Model, D. B. Magcale-Macandog, E. Abucay, P. A. B. Ani

IGC Proceedings (1997-2023)

In the Philippines, pure grasslands occupy 1.8 million ha and another 10.8 million ha (33% of the country's total land area) is under extensive cultivation mixed with grasslands and scrub. Most of these grasslands are under-utilised and dominated by Imperata cylindrica. Imperata grasslands generally represent areas of degraded soils that are acidic, low in organic matter and susceptible to erosion. However, conversion of these grassland areas into upland farms planted to annual crops and perennial trees is proliferating at a fast rate. This is triggered by the interacting factors of rapidly increasing population, the system of landholding, scarcity of …

Alternative Land Use Options For Philippine Grasslands: A Bioeconomic Modeling Approach Using The Wanulcas Model, D. B. Magcale-Macandog, E. Abucay, P. A. B. Ani

IGC Proceedings (1997-2023)

In the Philippines, pure grasslands occupy 1.8 million ha and another 10.8 million ha (33% of the country’s total land area) is under extensive cultivation mixed with grasslands and scrub. Most of these grasslands are under-utilised and dominated by Imperata cylindrica. Imperata grasslands generally represent areas of degraded soils that are acidic, low in organic matter and susceptible to erosion. However, conversion of these grassland areas into upland farms planted to annual crops and perennial trees is proliferating at a fast rate. This is triggered by the interacting factors of rapidly increasing population, the system of landholding, scarcity of …

Using Stable-Isotopes To Determine The Effects Of Land-Use Change On Carbon Storage, Morgan Basile

Undergraduate Student Research Internships Conference

Over the last century, there has been drastic conversion of natural vegetation to agriculture. The decomposition of plant tissue is transformed into soil organic matter that is rich in carbon and stored within soil aggregates. This research examines the effects of land-use change on carbon storage by using stable-isotopes of organic matter. The stable-isotopes of organic matter within aggregates will be used to quantify the amount of carbon that has been added to the soil after a change in land-use (e.g. restoration of agricultural land to grassland).

Loggerhead Shrike Detectability And Occurrence In Coastal South Carolina Urban Areas, Michelle Krauser

Electronic Theses and Dissertations

Grassland birds, such as the loggerhead shrike (Lanius ludovicianus), are threatened by extensive land-use change, including urbanization. Loggerhead shrikes have been declining since the early 1900s and are rare or extirpated in portions of their former range. Obtaining reliable population estimates of loggerhead shrikes is important to identify demographic trends and ensure conservation decisions are based on an accurate assessment of their current status. Imperfect detection, or the inability to detect every shrike during a survey, can result in biased population estimates. Estimating detection probability is labor-intensive and requires assumptions that are difficult to satisfy in most field studies. Understanding …

Decomposition Rates Of Organic Material Across Herbivore Treatments In A Nutrient-Rich Semi-Arid Sodic Savanna, L. L. Erasmus, H. Van Coller, S. Claassens, F. Siebert

IGC Proceedings (1997-2023)

Decomposition is a major determinant of terrestrial nutrient cycling and therefore an important regulator of ecosystem structure and function. It has been widely documented that large mammalian herbivores (LMH) act as a significant driver of changes to aboveground structure and modifications to edaphic properties. Little is known about the role of herbivory, and particularly the loss thereof, in mediating essential ecological processes in a herbivore-adapted system. The Nkuhlu exclosures, a large-scale, long-term exclusion experiment in the Kruger National Park, South Africa, provided an opportunity to explore the effects of herbivory and/or its long-term exclusion on decomposition and stabilisation of detrital …

Greater Loss And Fragmentation Of Savannas Than Forests Over The Last Three Decades In Yunnan Province, China, R Sedricke Lapuz, Angelica Kristina M. Jaojoco, Sheryl Rose C. Reyes, Jose Don T. De Alban, Kyle W. Tomlinson

SOSE Affiliate: Manila Observatory

Yunnan Province, southwest China, has a monsoonal climate suitable for a mix of fire-driven savannas and fire-averse forests as alternate stable states, and has vast areas with savanna physiognomy. Presently, savannas are only formally recognised in the dry valleys of the region, and a no-fire policy has been enforced nationwide since the 1980s. Misidentification of savannas as forests may have contributed to their low protection level and fire-suppression may be contributing to vegetation change towards forest states through woody encroachment. Here, we present an analysis of vegetation and land-use change in Yunnan for years 1986, 1996, 2006, and 2016 by …

A Pantropical Assessment Of Deforestation Caused By Industrial Mining, Stefan Giljum, Victor Maus, Nikolas Kuschnig, Sebastian Luckeneder, Michael Tost, Laura J. Sonter, Anthony J. Bebbington

Geography

Growing demand for minerals continues to drive deforestation worldwide. Tropical forests are particularly vulnerable to the environmental impacts of mining and mineral processing. Many local- to regional-scale studies document extensive, long-lasting impacts of mining on biodiversity and ecosystem services. However, the full scope of deforestation induced by industrial mining across the tropics is yet unknown. Here, we present a biome-wide assessment to show where industrial mine expansion has caused the most deforestation from 2000 to 2019. We find that 3,264 km2 of forest was directly lost due to industrial mining, with 80% occurring in only four countries: Indonesia, Brazil, Ghana, …

Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans

Electronic Theses and Dissertations

Understanding trends in the abundance and distribution of carnivores is important at global, regional and local scales due to their ecological role, their aesthetic and economic value, and the numerous threats to their populations. Carnivores in Maine range from the American black bear (Ursus americanus), to numerous native mesocarnivore species, such as American marten (Martes americana), fisher (Pekania pennanti), coyote (Canis latrans), red fox (Vulpes vulpes), bobcat (Lynx rufus), Canada lynx (Lynx canadensis) and to two small weasel species (Mustela erminea and Neogale frenata). …

Trade-Offs And Optimisation Of Land-Use For Pastoralism And Carbon In Southeastern Australia, Cathy M. Waters, D. M. Summers, B. Wang, J. Connor, D. L. Liu, M. Simpson

IGC Proceedings (1997-2023)

Globally, pressure to ensure future food security is being challenged by competing needs for multiple land-uses in agricultural systems. Rangelands are both a source of greenhouse gas emissions as well as providing opportunities for emissions reduction. Carbon farming is a new land-use option that sequesters carbon in vegetation and soils. National incentive programs in Australia for this option have resulted in significant recent land-use change across Australian rangelands.

Beyond the mitigation benefits, the potential for carbon farming income to enhance socio-ecological resilience in rangelands has been identified. However, there are major uncertainties about the impacts of climate change on sequestration …

On The Semantics Of Big Earth Observation Data For Land Classification, Gilberto Camara

Journal of Spatial Information Science

This paper discusses the challenges of using big Earth observation data for land classification. The approach taken is to consider pure data-driven methods to be insufficient to represent continuous change. I argue for sound theories when working with big data. After revising existing classification schemes such as FAO's Land Cover Classification System (LCCS), I conclude that LCCS and similar proposals cannot capture the complexity of landscape dynamics. I then investigate concepts that are being used for analyzing satellite image time series; I show these concepts to be instances of events. Therefore, for continuous monitoring of land change, event recognition needs …

Impacts Of Multiple Environmental Changes On Long‐Term Nitrogen Loading From The Chesapeake Bay Watershed, Shufen Pan, Zihao Bian, Hanqin Tian, Yuanzhi Yao, Raymond G. Najjar, Marjorie A.M. Friedrichs, Eileen E. Hofmann, Rongting Xu, Bowen Zhang

CCPO Publications

Excessive nutrient inputs from land, particularly nitrogen (N), have been found to increase the occurrence of hypoxia and harmful algal blooms in coastal ecosystems. To identify the main contributors of increased N loading and evaluate the efficacy of water pollution control policies, it is essential to quantify and attribute the long‐term changes in riverine N export. Here, we use a state‐of‐the‐art terrestrial–aquatic interface model to examine how multiple environmental factors may have affected N export from the Chesapeake Bay watershed since 1900. These factors include changes in climate, carbon dioxide, land use, and N inputs (i.e., atmospheric N deposition, animal …

The Role Of Culture In Land System Science, Kelly Hopping

Human-Environment Systems Research Center Faculty Publications and Presentations

Land system science (LSS) has substantially advanced understanding of land dynamics throughout the world. However, studies that explicitly address the causative role of culture in land systems have been fairly limited relative to those examining other structural dimensions (e.g. markets, policies, climate). In this paper, we aim to start a discussion on how to better include culture in LSS. Through four examples, we show how aspects of culture influence land systems in myriad ways. Building on existing causal land system models, we propose a conceptual framework for the role of culture in land use and summarize promising methodological innovations for …

The Signal Of Modern To Holocene Drivers Of Complex Channel Response Of A Small Alluvial Stream, Scott D. Ducar

Boise State University Theses and Dissertations

Small alluvial streams (~100km² drainage area) are important for water resources and aquatic habitat. Small streams throughout the Western United States are impacted by anthropogenic land-use including urban development, mining, logging, beaver trapping, grazing, and farming. Land-use change can trigger a complex series of channel response (such as stream channel incision or channel migration) that vary spatially and temporally in the watershed. However, streams also respond to other external forcings, such as tectonically or climatically-driven changes in discharge or base-level, which make disentangling the drivers of channel response complicated. Therefore, it is important to place modern channel changes into …

Spatial And Temporal Dynamics Of Human–Wildlife Conflicts In The Kenya Greater Tsavo Ecosystem, Joseph M. Mukeka, Joseph O. Ogutu, Erustus Kanga, Eivin Røskaft

Human–Wildlife Interactions

Biodiversity conservation in developing countries is faced with many and mounting challenges, including increasing human–wildlife conflicts (HWCs). In Africa and other developing countries, increasing HWCs, particularly those adjacent to protected areas, can adversely affect local stakeholder perceptions and support for conservation. We analyzed HWC reports for multiple wildlife species compiled >23 years (1995–2017) from the Greater Tsavo Ecosystem (GTE) in Kenya to determine HWC trends. The GTE is the largest protected area in Kenya, covering 22,681 km². Overall, 39,022 HWC incidents were reported in 6 GTE regions (i.e., Taveta, Mutomo, Kibwezi, Rombo, Galana, Bachuma). The 5 wildlife species …

Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina

Electronic Theses and Dissertations

Lake Auburn, Maine, USA, is a historically unproductive lake that has experienced multiple algal blooms since 2011. The lake is the water supply source for a population of ~60,000. We modeled past temperature, and concentrations of dissolved oxygen (DO) and phosphorus (P) in Lake Auburn by considering the watershed and internal contributions of P as well as atmospheric factors, and predicted the change in lake water quality in response to future climate and land-use changes. A stream hydrology and P-loading model (SimplyP) was used to generate input from two major tributaries into a lake model (MyLake) to simulate physical mixing, …

Tidal Erosion And Upstream Sediment Trapping Modulate Records Of Land-Use Change In A Formerly Glaciated New England Estuary, Justin L. Shawler, Christopher J. Hein, Elizabeth A. Canuel, Et Al

VIMS Articles

Land clearing, river impoundments, and other human modifications to theupland landscape and within estuarine systems can drive coastal change at local to regionalscales. However, as compared with mid-latitude coasts, the impacts of human modificationsalong sediment-starved formerly glaciated coastal landscapes are relatively understudied.To address this gap, we present a late-Holocene record of changing sediment accumulationrates and sediment sources from sediment cores collected across a tidal flat in theMerrimack River estuary (Mass., USA). We pairsedimentology, geochronology, bulk- andstable-isotope organic geochemistry, and hydrodynamic simulations with historical datato evaluate human and natural impacts on coastal sediment fluxes. During the 17th to19th centuries, accumulation rates …

Iceland's Migratory Birds In Changing Environmental Conditions: An Interactive Synthesis, Frances J. Duncan

Independent Study Project (ISP) Collection

Human-driven changes to environmental conditions alter the habitats, behaviors, and migration patterns of migratory species. Changes in temperature, vegetation, and precipitation are just some of the factors contributing to shifts in phenology, demography, and distribution of migratory birds. These changes are driven by anthropogenic climate change and amplified by human land-use change, and are especially intense at high latitudes. This project creatively communicates the effects of environmental changes on three species of migratory birds in Iceland—the northern wheatear, the Greenland white-fronted goose, and the black-tailed godwit—using principles of storytelling and game design. The resulting interactive product is a game that …

Soil And Land- Use Change Sustainability In The Northern Great Plains Of The Usa, Deepak Raj Joshi, David E. Clay, Alexander Smart, Sharon A. Clay, Tulsi P. Kharel, Umakanta Mishra

Agronomy, Horticulture and Plant Science Faculty Publications

In the Northern Great Plains (NGP), the combined impacts of land-use and climate variability have the potential to place many soils on the tipping point of sustainability. The objectives of this study were to assess if the conversion of grassland to croplands occurred on fragile landscapes in the North America Northern Great Plains. South Dakota and Nebraska were selected for this study because they are located in a climate transition zone. We visually classified 43,200 and 38,400 points in South Dakota and Nebraska, respectively, from high-resolution imagery in 2006, 2012, and 2014 into five different categories (cropland, grassland, habitat, NonAg, …

Impact Of Grassland Conversion To Forest On Groundwater Recharge In The Nebraska Sand Hills, Zablon A. Adane, Paolo Nasta, Vitaly A. Zlotnik, David A. Wedin

Department of Earth and Atmospheric Sciences: Faculty Publications

Study region: Nebraska National Forest in the High Plains Aquifer, Nebraska Sand Hills, U.S.A. Study focus: This research aimed to investigate the effects of grassland conversions to forest on recharge rates in a century-old experimental forest. The DiffeRential Evolution Adaptive Metropolis (DREAM_ZS) global optimization algorithm was used to calibrate the effective soil hydraulic parameters from observed soil moisture contents for 220 cm deep uniform soil profiles. The historical recharge rates were then estimated by applying the numerical model HYDRUS 1-D for simulation of two plots representing grasslands and dense pine forest conditions. New hydrological insights: The results indicate …

Past Role And Future Outlook Of The Conservation Reserve Program For Supporting Honey Bees In The Great Plains, Clint R.V. Otto, Haochi Zheng, Alisa L. Gallant, Rich Iovanna, Benjamin L. Carlson, Matthew D. Smart, Skip Hyberg

United States Geological Survey: Staff Publications

Human dependence on insect pollinators continues to grow even as pollinators face global declines. The Northern Great Plains (NGP), a region often referred to as America’s last honey bee (Apis mellifera) refuge, has undergone rapid land-cover change due to cropland expansion and weakened land conservation programs. We conducted a trend analysis and estimated conversion rates of Conservation Reserve Program (CRP) enrollments around bee apiaries from 2006 to 2016 and developed models to identify areas of habitat loss. Our analysis revealed that NGP apiaries lost over 53% of lands enrolled in the CRP, and the rate of loss was highest in …

Understanding The Past, Present, And Future Of Land Conservation In South Carolina, Nicole Berson

Graduate Theses

Urbanization poses a significant challenge for many ecosystems in the United States. However, monitoring its impacts requires extensive data and this lack of up-to-date information makes understanding the impacts of urbanization difficult to assess. One area that has seen tremendous growth is the Interstate 85 (I-85) corridor between Charlotte, NC and Atlanta, GA, which is known as “The Boom Belt.” Unfortunately, due to limited resources from conservation and state agencies, data on land use change and its impacts in this area have not been updated since the early 1990s. To investigate how urbanization is impacting this region, I conducted a …

A Realistic Meteorological Assessment Of Perennial Biofuel Crop Deployment: A Southern Great Plains Perspective, Melissa Wagner, Meng Wang, Gonzalo Miguez-Macho, Jesse Miller, Andy Vanloocke, Justin E. Bagley, Carl J. Bernacchi, Matei Georgescu

Andy VanLoocke

Utility of perennial bioenergy crops (e.g., switchgrass and miscanthus) offers unique opportunities to transition toward a more sustainable energy pathway due to their reduced carbon footprint, averted competition with food crops, and ability to grow on abandoned and degraded farmlands. Studies that have examined biogeophysical impacts of these crops noted a positive feedback between near-surface cooling and enhanced evapotranspiration (ET), but also potential unintended consequences of soil moisture and groundwater depletion. To better understand hydrometeorological effects of perennial bioenergy crop expansion, this study conducted high-resolution (2-km grid spacing) simulations with a state-of-the-art atmospheric model (Weather Research and Forecasting system) dynamically …

Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi

Andy VanLoocke

The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model-based approaches have investigated biogeochemical trade-offs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (a), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here, …

Effects Of Climate Change And Anthropogenic Modification On A Disturbance-Dependent Species In A Large Riverine System, Sara L. Zeigler, Daniel H. Catlin, Mary Bomberger Brown, James D. Fraser, Lauren R. Dinan, Kelsi L. Hunt, Joel G. Jorgensen, Sarah M. Karpanty

School of Natural Resources: Faculty Publications

Humans have altered nearly every natural disturbance regime on the planet through climate and land-use change, and in many instances, these processes may have interacting effects. For example, projected shifts in temperature and precipitation will likely influence disturbance regimes already affected by anthropogenic fire suppression or river impoundments. Understanding how disturbance-dependent species respond to complex and interacting environmental changes is important for conservation efforts. Using field-based demographic and movement rates, we conducted a metapopulation viability analysis for piping plovers (Charadrius melodus), a threatened disturbance-dependent species, along the Missouri and Platte rivers in the Great Plains of North America. …

Primary Production In The Delta: Then And Now, James E. Cloern, April Robinson, (...), Elizabeth A. Canuel, Et Al

VIMS Articles

To evaluate the role of restoration in the recovery of the Delta ecosystem, we need to have clear targets and performance measures that directly assess ecosystem function. Primary production is a crucial ecosystem process, which directly limits the quality and quantity of food available for secondary consumers such as invertebrates and fish. The Delta has a low rate of primary production, but it is unclear whether this was always the case. Recent analyses from the Historical Ecology Team and Delta Landscapes Project provide quantitative comparisons of the areal extent of 14 habitat types in the modern Delta versus the historical …

Land Conservation In Northern New England: Historic Trends And Alternative Conservation Features, Spencer Meyer, Christopher Cronan, Robert J. Lilieholm, Michelle Johnson, David Foster

Publications

Protected areas (PAs) are an important component of the global conservation strategy and understanding the past drivers of land protection can inform future conservation planning. Socioeconomic and policy drivers of protection vary through time and space, but a lack of spatio-temporal data limit the ability to conduct retrospective analyses of PAs. We developed a spatio-temporal database covering 90% of area in PAs in northern New England in the U.S. to quantify trends in the extent, rate of increase, ownership characteristics, and level of protection from 1800 to 2010. We found an accelerating rate of protection and an increase in the …

Unintended Outcomes Of Farmers' Adaptation To Climate Variability: Deforestation And Conservation In Calakmul And Maya Biosphere Reserves, Claudia Rodriguez-Solorzano

Dartmouth Scholarship

Minimizing the impact of climate change on farmer livelihoods is crucial, but adaptation efforts may have unintended consequences for ecosystems, with potential impacts on farmers’ welfare. Unintended outcomes of climate adaptation strategies have been widely discussed, however, empirical exploration has been neglected. Grounded in scholarship on climate adaptation, environmental governance, social–ecological systems, and land-use change, this paper studies whether farmers’ climate adaptation contributes to deforestation or forest conservation. The paper draws on interviews with 353 farmers from 46 communities in Calakmul Biosphere Reserve in Mexico and Maya Biosphere Reserve in Guatemala. Farmers in the area of study have implemented adaptation …

Reviewing Models Of Land Availability And Dynamics For Biofuel Crops In The United States And The European Union, Ruopu Li, Nicola Di Virgilio, Qingfeng Guan, Song Feng, Goetz M. Richter

School of Natural Resources: Faculty Publications

The biofuel-related land use in the USA and the EU has significantly expanded during the last decade; models have been used to estimate land availability and demand in these regions. This paper provides an overview of different land-use modeling practices applicable to first- and second-generation biofuels. We review the importance of different land categories for biofuels, modeling approaches (top-down/bottom-up) and their integration, data availability for calibration and validation, model scale, and uncertainty. Possible future changes of biofuel land use and research gaps and limitations are synthesized. Key issues are the lack of data for independent validation and the need for …

Restoring Native Forest Understory: The Influence Of Ferns And Light In A Hawaiian Experiment, Rachelle K. Gould, Harold Mooney, Laura Nelson, Robert Shallenberger, Gretchen C. Daily

Rubenstein School of Environment and Natural Resources Faculty Publications

Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1) overstory shade and (2) possible facilitation by a fern (Dryopteris wallichiana), one of few native colonists of pasture in our montane Hawai'i study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings …

Changes To Land Tenure And Pastoral Lease Ownership In Western Australia's Central Rangelands: Implications For Co-Operative, Landscape-Scale Management, Eddie J. Van Etten

Research outputs 2013

The majority of arid and semiarid land in the Western Australian pastoral zone has a long history of livestock grazing within an extensive network of predominantly family-held pastoral leases. A variety of different groups have purchased pastoral leases in the last five decades and, for many, making a profit from pastoralism is no longer a priority. For the central rangelands of Western Australia, these groups have included: government agencies, who have purchased some 9% of pastoral leases by area; private conservation organisations (<1% purchased); aboriginal communities and groups (∼7%); and mining companies (∼13%). The purchases of pastoral leases by government agencies was designed to improve the conservation status of arid-zone ecosystems, and is the first step in a process of changing land tenure to a conservation reserve. This paper summarises the extent and other characteristics of these changes in land tenure and ownership of pastoral leases, and explores the implications for land management and conservation, stemming from these changes. It demonstrates that large areas of contiguous land with no or reduced domestic stocking can now be found in many parts of these rangelands, particularly in the Coolgardie, Yalgoo and Pilbara bio-regions, with some leaseholders actively managing land for the conservation of biodiversity and restoring sites degraded through past over-grazing. In some bio-regions, such land covers considerable proportions of sub-catchments, suggesting that broad-scale conservation management and restoration objectives may be realised. It is argued that to fully realise these objectives requires effective communication and co-ordination between land managers, including sharing of ideas, view-points and resources. In particular, mining companies, now major holders of pastoral leases in Western Australia, can play an important role in contributing to and even facilitating such objectives.