Plant Biology Commons^™

Comparative Analysis Of Climate Change Adaptation Options Across The Southern Australian Livestock Industry, Afshin Ghahramani, Andrew D. Moore

IGC Proceedings (1977-2023)

Climate change is predicted to have a substantial negative effect on the productivity of grasslands across southern Australia (Moore and Ghahramani 2013). We used the GRAZPLAN biophysical simulation models to assess several possible grassland management and animal genetic improvement adaptations under SRES A2 climate change scenario. Simulations spanned the five dimensions of geography, time, global circulation models, enterprise, and adaptations. Impact of climate change was predicted to reduce profitability of livestock industry by 46%, 58%, and 72% at 2030, 2050 and 2070, respectively. Increasing soil fertility could return the average profitability of five livestock enterprises to its historical level at …

Modelling Adaptation And Mitigation Strategies For Southern Livestock Industries Of Australia, Richard J. Eckard, Richard P. Rawnsley, Brendan R. Cullen, Matthew Bell, Karen Christie

IGC Proceedings (1977-2023)

Climate change will impact on the Australian grazing industries both through mitigation policies and the impact of warmer temperatures, increased atmospheric CO₂ and changed rainfall patterns (Cullen et al. 2009; Eckard et al. 2010). Mechanistic models are useful tools to inform our understanding of the complex interactions between future climates and the soil, plant, animal and management in livestock production systems.

This paper summarises the results of a number of whole farm systems modelling studies investigating likely impacts of climate change, adaptation options and emissions implications for livestock production in southern Australia.

Challenges And Opportunities For Improving Eco-Efficiency Of Tropical Forage-Based Systems To Mitigate Greenhouse Gas Emissions, Michael Peters, Mario Herrero, Myles Fish, Karl-Heinz Erb, Idupulapati M. Rao, Guntur V. Subbarao, Aracely Castro, Jacobo Arango, Julian Chará, Enrique Murgueitio, Rein Van Der Hoek, Peter Läderach, Glenn Hyman, Jeimar Tapasco, Bernardo Strassburg, Birthe K. Paul, Alvaro Rincón, Rainer Schultze-Kraft, Steve Fonte, Timothy Searchinger

IGC Proceedings (1977-2023)

Forage-based livestock production plays a key role in national and regional economies, for food security and poverty alleviation. Livestock production is also considered as a major contributor to agricultural GHG emissions, however. While demand for livestock products is predicted to continue to increase, there is political and societal pressure both to reduce environmental impacts and to convert some of the pasture area to alternative uses such as crop production and environmental conservation. Thus it is essential to develop approaches for sustainable intensification of livestock systems to mitigate GHG emissions, addressing biophysical, socioeconomic and policy challenges. This paper highlights the potential …

Drought In Temperate Mesic Regions Leads To Micro-Density Anomalies In White Pine, Elise Miller

CSB and SJU Distinguished Thesis

Wood density and wood volume determine the amount of carbon fixed by trees; however, while we are beginning to understand normal seasonal variation in wood density, anomalies are common, and their drivers are poorly understood. In conifers, wood density normally increases continuously throughout the season, but intra-annual fluctuations in wood density can occur and have been linked to climatic events. The causes of these fluctuations in density at the micro-scale (hereafter micro-density anomalies) are still debated.

Mesic regions are experiencing more droughts, but micro-density anomalies are rarely studied in these ecosystems. This study examined micro-density anomaly distribution within the boles …

Seed Source Regions Drive Fitness Differences In Invasive Macrophytes, Morgane B. Gillard, Rebecca E. Drenovsky, Gabrielle Thiébaut, Michèle Tarayre, Caryn J. Futrell, Brenda J. Grewell

2020 Faculty Bibliography

Premise Worldwide, ecosystems are threatened by global changes, including biological invasions. Invasive species arriving in novel environments experience new climatic conditions that can affect their successful establishment. Determining the response of functional traits and fitness components of invasive populations from contrasting environments can provide a useful framework to assess species responses to climate change and the variability of these responses among source populations. Much research on macrophytes has focused on establishment from clonal fragments; however, colonization from sexual propagules has rarely been studied. Our objective was to compare trait responses of plants generated from sexual propagules sourced from three climatic …

Solar Dimming Decreased Maize Yield Potential On The North China Plain, Qingfeng Meng, Baohua Liu, Haishun Yang, Xinping Chen

Department of Agronomy and Horticulture: Faculty Publications

Solar dimming has been increasing in rapidly developing regions (China and India) and threatening food security. Although previous studies have summarized the ef- fects of climate change-associated increases in temperature on agriculture, few have examined the effects due to solar dimming. Here, we analyzed the effects of solar dimming on maize on the North China Plain (NCP). It is reported that solar dimming intensified and maize yield potential decreased since the 1960s. The total decrease in solar radiation for the whole maize growing season of this period was 17%, and solar dimming explained 87% of the decrease in yield potential. …

The Italian Catalogue Of Herbage Varieties, M. Giolo, Giovanni Corsi, N. Mugueta, F. Sorgoni, Pier Giacomo Bianchi, Renzo Torricelli, Mario Falcinelli

IGC Proceedings (1977-2023)

With 3.4 million hectares, permanent grassland covers 25.8% of Italian U.A.A. (Usable Agricultural Area). Most of this is located in hilly and mountainous areas and is important for the stability of the soil even if their productivity is low. Alfalfa and annual forages cover 1.8 million hectares (C.R.P.A. 2010). Italy’s large longitudinal extension (between latitudes 35° and 47° N), delivers a great variety of climates (Fig. 1). The northern regions bordering the rest of Europe differ greatly from the southern regions surrounded by the Mediterranean Sea.

The Use Of Functional Traits To Identify Grasses And Fodder Shrubs For Domestication To Suit A Changing Climate, Meredith L. Mitchell, R. D. B. Whalley, Hayley C. Norman

IGC Proceedings (1977-2023)

There is uncertainty about future climatic predictions; however there is little doubt amongst experts that the future will be warmer. Climate change and the associated elevation in atmospheric CO₂ level and temperatures will provide novel challenges and potential opportunities for cultivated plant species. Plant breeding and domestication can contributed to improvements in both yield and quality of grasses and fodder shrubs. A range of key functional traits is required to cope with this changing climate. The main challenges that are discussed are new pests and pathogens; changes in the pattern of nutrient supply and forage quality; challenge associated with …

Climate Change Increasing Threats On Non-Conserved Mangroves Forests Of Micheweni, Zanzibar–Tanzania, Haji M. Hamad, Islam S.S. Mchenga, Mariam I. Hamisi

Tanzania Journal of Science

Overutilization of mangroves has been reported as the factor for mangrove declining across the globe. However, currently, the global climate change has been claimed to pose significant threats to the survival of mangroves. This study analysed the impacts of climatic variability (sea level rise, temperature and precipitation) to the mangroves of Micheweni (non reserve) and Ngezi-Vumawimbi (nature forest reserve). Multi-disciplinary approach was employed to collect information on community perceptions. Secondary time series data of up to 30 years for temperature, rainfall and sea level rise were collected and analysed. Inquiry results on how local communities perceived climate change showed that …

Summer Dormancy And Survival Of Tall Fescue In Relation To Endophyte Presence, J. L. Thomas, Charles P. West, D. P. Malinowski

IGC Proceedings (1977-2023)

True summer dormancy in temperate perennial grasses is the ability to survive summer stresses by ceasing growth and senescing vegetative tissues independently of water supply, as opposed to summer-active grasses, which respond to rains by continuing growth, but senesce during droughts (Volaire and Norton 2006). Summer dormancy is a common drought-escape mechanism for Mediterranean-origin perennial grasses, but is also being considered as a potentially useful trait in semiarid to humid zones whose climates are not strictly Mediterranean, but where temperate grass survival is threatened by summer heat and water deficits (Malinowski et al. 2005). Moreover, summer dormancy may provide …

Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones

Honors Scholar Theses

Vesicular-arbuscular mycorrhizae (VAM) are an ancient mutualism in which soil-dwelling fungi enhance plant absorption of phosphorus and nitrogen in exchange for photosynthates. VAM are sensitive to changes in soil moisture and nutrient content, fluctuating between mutualism and parasitism depending on conditions of drought stress and nutrient deficiency. Understanding how VAM respond to precipitation changes is crucial for both conservation and agricultural purposes. To test how soil moisture changes the effects of VAM colonization and growth in little bluestem (Schizachyrium scoparium), a common prairie grass, I planted 300 seeds in a greenhouse in sterilized soil and soil inoculated with …

Australian Grasslands Research At The Crossroads, Alan Robson

IGC Proceedings (1977-2023)

Grasslands research in Australia is at a crossroad. There are several difficulties. First, the decline of sheep production and dairying within Australia and increased cropping has focused attention on crop research rather than pasture research. Second, enrolments in agricultural and related education have declined, and graduate numbers are insufficient to meet demand for expertise. Third, there has been a move towards specialisation in research and there are relatively few generalist agricultural scientists able to integrate research results into agricultural ecosystems. There remain very many challenges. Adapting grassland production to minimize the emission of carbon dioxide and methane is a major …

Managing Grassland Systems In A Changing Climate: The Search For Practical Solutions, Jean-François Soussana, Luis Gustavo Barioni, Tamara Ben Ari, Rich Conant, Pierre Gerber, Petr Havlik, Alexandre Ickowicz, Mark Howden

IGC Proceedings (1977-2023)

By the end of the XXI^st century, a global temperature rise between 1.5 and 4°C compared to 1980-1999 and CO₂ concentrations in the range 550-900 ppm are expected, together with an increased frequency of extreme climatic events (heat waves, droughts, and heavy rain) that is likely to negatively affect grassland production and livestock systems in a number of world regions. Grassland management has a large potential to mitigate livestock greenhouse gas emissions at a low (or even negative) cost, by combining a moderate intensification, the restoration of degraded pastures and the development of silvo-pastoral systems. Climate change vulnerability …

Diffuse Light And Wetting Differentially Affect Tropical Tree Leaf Photosynthesis, Z. Carter Berry, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

‐Most ecosystems experience frequent cloud cover resulting in light that is predominantly diffuse rather than direct. Moreover, these cloudy conditions are often accompanied by rain that results in wet leaf surfaces. Despite this, our understanding of photosynthesis is built upon measurements made on dry leaves experiencing direct light.

‐Using a modified gas exchange setup, we measured the effects of diffuse light and leaf wetting on photosynthesis in canopy species from a tropical montane cloud forest.

‐We demonstrate significant variation in species‐level response to light quality independent of light intensity. Some species demonstrated 100% higher rates of photosynthesis in diffuse light …

Effects Of Increased Precipitation On The Life History Of Spring- And Autumn-Germinated Plants Of The Cold Desert Annual Erodium Oxyrhynchum (Geraniaceae), Yanfeng Chen, Xiang Shi, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Huiliang Liu, Daoyuan Zhang

Biology Faculty Publications

Future increased precipitation in cold desert ecosystems may impact annual/ephemeral plant species that germinate in both spring and autumn. Our primary aim was to compare the life history characteristics of plants from spring-germinating (SG) and autumn-germinating (AG) seeds of Erodium oxyrhynchum. Plants in field plots with simulated increases in precipitation of 0, 30 and 50 % in spring and summer were monitored to determine seedling survival, phenology, plant size, seed production and biomass accumulation and allocation. Germination characteristics were determined in the laboratory for seeds produced by plants in all increased precipitation treatments. Increased precipitation in spring significantly improved survival …

Biogeochemical Response To Vegetation And Hydrologic Change In An Alaskan Boreal Fen Ecosystem, Danielle L. Rupp

Dissertations, Master's Theses and Master's Reports

Boreal peatlands store approximately one third of the earth’s terrestrial carbon, locked away in currently waterlogged and frozen conditions. Peatlands of boreal and arctic ecosystems are affected increasingly by shifting hydrology caused by climate change. The consequences of these relatively rapid ecosystem changes on carbon cycling between the landscape and the atmosphere could provide an amplifying feedback to climate warming. Alternatively, the advancement of terrestrial vegetation into once waterlogged soils could uptake carbon as a sink. Previous work suggests that fens will become an increasingly dominant landscape feature in the boreal. However, studies investigating fens, their response to hydrologic and …

Hydraulic Mechanisms Of Fungal-Induced Dieback In A Keystone Chaparral Species During Unprecedented Drought In California, Natalie M. Aguirre, Marissa E. Ochoa, Helen I. Holmlund, Frank E. Ewers, Stephen D. Davis

Seaver College Research And Scholarly Achievement Symposium

Between 2012-2016, southern California experienced unprecedented drought that caused dieback in Malosma laurina, a keystone species of chaparral shrub communities. Dieback was especially severe in coastal exposures of the Santa Monica Mountains, leading to whole plant mortality exceeding 50% at some sites. We hypothesized that the endophytic fungus causing the dieback, Botryosphaeria dothidea, was successful in invading the xylem tissue of M. laurina because of protracted water stress, carbon starvation, or a combination of the two. We tested these possibilities in a controlled pot experiment by comparing three treatments, each inoculated with the fungus: (1) irrigated controls (2) …

Effects Of In-Situ Leaf-Level Canopy Warming In A Northern Hardwood Forest, Kelsey Carter

Dissertations, Master's Theses and Master's Reports

Rising mean annual temperatures due to climate change have intensified the need to understand the effects of warming on plant physiological processes. Forest photosynthesis is the most important pathways of terrestrial carbon sequestration, yet continued warming could reduce this important carbon sink. Photosynthesis is highly sensitive to temperature and begins to decline after an optimum temperature (T_opt) is reached, leading to reduced carbon uptake. To date, logistical difficulties have limited our ability to test photosynthetic responses to sustained warming in mature forest canopies. In order to understand how elevated temperatures will affect forest ecosystems, we need to be …

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson

Biology ETDs

The Southwestern US is predicted to become hotter and drier, as global climate change forces increasing temperatures and variability in timing and size of precipitation inputs. Drought stress has become more frequent in recent decades, and resulted in massive forest mortality in piñon-juniper woodlands. During recent severe droughts (2000-2003, 2009-2012), piñon pine (Pinus edulis Englem.) suffered disproportionately high mortality compared to co-occurring one-seed juniper (Juniperus monosperma [Engelm.] Sarg.). A large-scale precipitation manipulation experiment was established in a piñon-juniper woodland in central New Mexico to test hypotheses regarding tree survival and mortality with respect to altered water regimes. Our …

Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole

DePaul Discoveries

Isoprene, the most abundant hydrocarbon in the atmosphere, plays a significant role in atmospheric chemistry. Its reactions with NO_x lead to the formation of ozone in the lower troposphere, which is harmful to plants and detrimental to human health. As air temperatures and CO₂ concentrations increase with climate change, it is uncertain how isoprene emissions from plants will respond. We hypothesized that isoprene emissions will increase with the combination of increasing temperature and CO­₂ concentrations. We predict that oaks grown at a higher temperature will exhibit an increase in isoprene emissions with combined short-term increases in temperature …

Long-Term Sandhills Prairie Responses To Precipitation, Temperature, And Cattle Stocking Rate, John A. Guretzky, Cheryl Dunn, Heidi L. Hillhouse

Department of Agronomy and Horticulture: Faculty Publications

Understanding of Sandhills prairie, the most expansive sand dune region stabilized by perennial grasses in the Western Hemisphere, is limited by lack of long-term vegetation data. We used a 26-year dataset to evaluate Sandhills prairie responses to yearto- year variation in precipitation, temperature, and cattle stocking rate. Basal cover, a measurement that is constant seasonally and used to detect long-term changes in bunchgrass vegetation, was measured in 38–40 permanent plots positioned along four transects spanning 769 ha from 1979 to 2007. Across this period, total basal cover averaged 2.4 % and was dominated by warm-season grasses (81.1 %). Schizachyrium scoparium …

Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez

Department of Agronomy and Horticulture: Faculty Publications

It is critical to evaluate conservation practices that protect soil and water resources from climate change in the Midwestern United States, a region that produces one-quarter of the world’s soybeans and one-third of the world’s maize. An over-winter cover crop in a maize–soybean rotation offers multiple potential benefits that can reduce the impacts of higher temperatures and more variable rainfall; some of the anticipated changes for the Midwest. In this experiment we used the Agricultural Production Systems sIMulator (APSIM) to understand how winter rye cover crops impact crop production and environmental outcomes, given future climate change. We first tested APSIM …

Disaggregating The Effect Of Drought And Heat Stress During Flowering On Spikelet Fertility In Rice, Lisa Straussberger

Graduate Theses and Dissertations

Due to rice’s wide geographic distribution, extending from 50°N to 35°S, rice is

forecasted to be the most vulnerable crop to warming global climates. Previous studies have

predicted lower rice yields and increasing rice yield variability due to higher frequencies of heat

stress events, and a higher variability in precipitation patterns due to global warming. As such,

understanding the effects of drought and heat stress intensity and frequency on rice yields is of

upmost importance to feeding the growing global population.

Given that drought and high-temperature stress often occur together, it is essential to

disaggregate the two individual stressors and …

Climate Change Impact And Adaptation In Temperate Grassland And Livestock Industries, Afshin Ghahramani, Andrew D. Moore

IGC Proceedings (1977-2023)

Climate is projected to have negative impact on temperate grassland and livestock productions across the globe. Moderately elevated atmospheric CO₂ in the near future is expected to increase plant photosynthetic rates but this is likely to be limited by soil nitrogen deficits. However, in Australia at least it is unlikely that positive effect of elevated CO₂ on plant production be able to offset the negative impacts of climate change. Currently there is a considerable gap between actual and achievable production and profit in Australian grazing systems and many management and genetic improvements for climate adaptation would operate by …

Rainwater Harvesting And Its Impact On Farming Systems, J. S. Samra

IGC Proceedings (1977-2023)

Landless, small holders and other poors supplement their livelihood and adapt to climate change by grazing, stall feeding with crop residues and fodder cultivated under rainfed and irrigated conditions. Improving productivity by conserving rainfall, ground water recharging, harvesting and recycling of rainwater especially in degraded open access or shared land with community participation was quite successful over a wide range of precipitation and ecological situations. Various types of trenches, bunding, vegetative barriers, gully plugs, ponds, check dams, land slides and mine spoils stabilization etc. retained more soil moisture, seeds, vegetative propagules etc. in situ and prevented soil erosion. It regenerated …

Emission Of Green House Gases From Grasslands And Their Mitigation, Prem N. Sharma, Shyam Khadka

IGC Proceedings (1977-2023)

The concentrations of green house gases (GHG) in the atmosphere began in pre-industrial times and it continues to increase. This could result into an alarming increase in temperature of up to 5.4 ^oC by year 2100 due to a net global annual GHG emission of H 4.5-6.5 Gt C equivalent. About 18% of the world’s GHG are contributed by livestock and related activities on grasslands that are spread over almost 35 million Km².These grasslands give livelihood to over a billion people most of who are poor. Twenty to 70% of the land surface area is degrading often …

Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen

Biological Sciences Faculty Research

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of …

Ecophysiological Responses Of Tall Fescue Genotypes To Endophyte Infection And Climate Change, Marie Bourguignon

Theses and Dissertations--Plant and Soil Sciences

Tall fescue is a widely used forage grass in the eastern USA and can form a symbiosis with a fungal endophyte, which can be beneficial for the plant but can cause livestock health issues. Little is known regarding the symbiotic response to predicted climate change. To address this knowledge gap, I analyzed tall fescue variety trial data collected throughout the U.S., exploring relationships between climate variables and yield for two different fescue cultivars that were either endophyte-free or infected. This study showed no endophyte or cultivar effect on fescue yield, but identified temperature, precipitation and location as significant predictors of …

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn

Featured Research

Our project investigated the relationship between climate change and vegetation type conversion in the Santa Monica Mountains on north and south facing slopes. Our hypothesis is that with a shift in climate towards dryer, hotter, and longer summers, and shorter and dryer winters, we will see a shift in the density of native chaparral in the Santa Monica mountains, and possibly an influx of non-native species. We tested this hypothesis by choosing three study sites that were on north/south ridgelines to simulate a dryer, harsher climate (south) and a more temperate climate (north). Using the point-quarter method to measure the …