Plant Sciences Commons^™

Optimising Management To Achieve Sustainable Economic Yields From Grasslands, Karl Behrendt

IGC Proceedings (1997-2023)

This paper describes the output from the integration of a dynamic pasture resource development (DPRD) simulation model into a seasonal stochastic dynamic programming (SSDP) model. The combined modelling process was used to identify optimal tactical and strategic decision rules that achieve maximum economic yields from a grassland resource under climatic uncertainty on a sustainable basis. The model was calibrated based on the Cicerone farmlet experiment (Behrendt et al. 2013a).

Resilience And Degradation In A Tropical Wetland Overgrazed By Cattle, Sandra A. Santos, Humberto L. Perotto-Baldivieso, Dylan Young

IGC Proceedings (1997-2023)

The Pantanal, one of the largest wetlands in the world, is highly valued for its diversity of flora and fauna, and the dynamic hydrological regime, combined with heterogeneous topography, has resulted in a mosaic of diverse habitats types in terms of species and physical structure. However, the Pantanal floodplains are also important for beef cattle production due to the abundance of forage resources. Cattle prefer grazing near water bodies because these areas have high quality forage as a result of flooding regimes (Santos et al. 2002). Many wetlands go through a wet/dry cycle that is essential to maintain their …

Estimating Pasture Land Cover In The New England Region Of Northern New South Wales, Graham E. Donald, Mark Trotter, Elizabeth L. Hulm

IGC Proceedings (1997-2023)

Land cover across the southern Australian temperate agricultural region comprises primarily of native pasture, introduced improved pastures and crops for livestock production and also perennial remnant vegetation. A feed-base pasture audit was carried out throughout southern Australia commencing mid-year 2011 (Donald and Burge 2012; Donald et al. 2012). The purpose of the audit was to map and analyse information obtained about the pasture feed-base for livestock production by surveying Statistical Local Areas (SLAs) across the southern states. The purpose of this Feed-Base audit was to survey pastures within agricultural NSW, Victoria, Tasmania, South Australia and South-Western Australia, collate these …

Availability Of Soil Mutualists May Not Limit Non‐Native Acacia Invasion But Could Increase Their Impact On Native Soil Communities, Elizabeth M. Wandrag, Christina Birnbaum, Metha M. Klock, Luke G. Barrett, Peter H. Thrall

Faculty Publications, Environmental Studies

1. The availability of compatible mutualistic soil microbes could influence the invasion success of non-native plant species. Specifically, there may be spatial variation in the distribution of compatible microbes, and species-specific variation in plant host ability to associate with available microbes. Although either or both factors could promote or limit invasion, the scale over which most studies are conducted makes it difficult to examine these two possibilities simultaneously. However, this is critical to identifying a role of soil microbes in invasion.
2. A series of recent research projects focused on interactions between Australian Acacia and nitrogen-fixing bacteria (rhizobia) at multiple spatial scales, …

An Efficient Sampling Protocol For Sagebrush/Grassland Monitoring, Larry L. Larson, Mounir Louhaichi, Patrick E. Clark, Douglas E. Johnson

IGC Proceedings (1997-2023)

Rangeland scientists and quantitative ecologists have developed numerous methods and monitoring techniques that can be used for vegetation sampling (Barbour et al. 1987). The methods used to position samples (transects, quadrats, lines, and points) vary and can be classed as selective, capricious, systematic, or random. One of the prerequisites for valid statistical inference is that samples are taken randomly. A random sampling procedure implies that all elements or units of the population being studied have an equal chance of being represented in the sample. It also implies that selection of an element or unit does not influence the chance …

Landscape Change In Arid And Semi-Arid Rangeland Of Borana, Southern Ethiopia: Implication For Management, Teshome Abate, A. Angassa

IGC Proceedings (1997-2023)

The Borana rangelands in southern Ethiopia (between 4°3’N to 5°0’N and 37°4’E to 38°2’E) comprise important cultural landscapes with a unique feature of the tula-well landscapes. Until a few decades ago, the Borana rangelands were considered one of the most productive and resilient ecosystems in East Africa. In recent years, however, the Borana rangelands have undergone a large reduction in grassland cover probably as a result of anthropogenic and natural-induced factors (Coppock 1994), with consequences on the livelihood of the local communities. Therefore, the objective of the study was to investigate the dynamics of landscape change in the Borana …

Calibration Of The Rising Plate Meter For Pasture Yield Determination In Kikuyu (Pennisetum Clandestinum) Over-Sown With Ryegrass (Lolium Spp.), Janke Van Der Colf, Philip R. Botha, Robin Meeske, Wayne F. Truter

IGC Proceedings (1997-2023)

Accurate feed budgeting and management of forage in grazing systems requires frequent assessment of forage mass and growth of pastures (Gabriёls and Van den Berg 1993; Sanderson et al. 2001). The rising plate meter (RPM) developed by Earle and McGowan (1979) has been used widely by researchers and farmers to estimate pasture dry matter (DM) production. The advantages associated with using the RPM for the estimation of pasture DM yield include its low sensitivity to environmental conditions, stability of calibration equations across years and seasons (if pasture composition remains similar), and the fact that its robustness and ease of …

Spatial Gis Database For Adaptive Grassland Management In Dudhwa National Park, India, Neha Midha, Pradeep K. Mathur

IGC Proceedings (1997-2023)

Ecologically important tall grasslands of Dudhwa National Park (DNP) in Northern India are being threatened by various natural and biotic factors including varying grassland burning regimes viz. cut and burn, harrowed and burn, or only burn adopted by management for their maintenance (De 2001). Uncertainty regarding resultant grassland composition and disturbance to grassland obligate species prompted the management and scientific communities concerned to develop an adaptive management strategy for long term conservation goals (Chadden et al. 2004). In view of this, the present study attempted to develop comprehensive GIS (Geographic Information System) spatial database and associated hard copy …

Describing Ecological Potential And Ecological States Of Rangeland To Support Livestock Management In Mongolia, D. Bulgamaa, Brandon T. Bestelmeyer, U. Budbaatar, S. Sumjidmaa, T. S. Enkh-Amgalan, J. W. Van Zee, B. Bolormaa, L. Otgontuya

IGC Proceedings (1997-2023)

Perception of rangeland degradation in Mongolia and its causes are well known but herders and policy makers lack clear messages on how much rangeland is degraded, whether is it reversible, and what management changes should be implemented. This paper illustrates a portion of our ongoing efforts to develop ESDs that can be used at the grass roots level as management tools. At the Undurshireet soum study site, which is split mainly into Gravelly, Loamy, Sandy, and Deep sandy ecological sites, rangeland community shifts in Gravelly and Loamy ecological sites are interpreted as reversible shifts in species composition or species proportion …

Nitrogen Fertilization Restructured Spatial Patterns Of Soil Organic Carbon And Total Nitrogen In Switchgrass And Gamagrass Croplands In Tennessee Usa, Jianwei Li, Siyang Jian, Chad S. Lane, Chunlan Guo, Yuehan Lu, Qi Deng, Melanie A. Mayes, Kudjo E. Dzantor, Dafeng Hui

Agricultural and Environmental Sciences Faculty Research

Nitrogen (N) fertilizers can potentially alter spatial distribution of soil organic carbon (SOC) and total nitrogen (TN) concentrations in croplands such as switchgrass (SG: Panicum virgatum L.) and gamagrass (GG: Tripsacum dactyloides L.), but it remains unclear whether these effects are the same between crops and under different rates of fertilization. 13C and 15N are two important proxy measures of soil biogeochemistry, but they were rarely examined as to their spatial distributions in soil. Based on a three-year long fertilization experiment in Middle Tennessee, USA, the top mineral horizon soils (0–15 cm) were collected using a spatially explicit design within …

Enhancing Hybrid Prediction In Pearl Millet Using Genomic And/Or Multi- Environment Phenotypic Information Of Inbreds, Diego Jarquin, Reka Howard, Zhikai Liang, Shashi K. Gupta, James C. Schnable, Jose Crossa

Department of Agronomy and Horticulture: Faculty Publications

Genomic selection (GS) is an emerging methodology that helps select superior lines among experimental cultivars in plant breeding programs. It offers the opportunity to increase the productivity of cultivars by delivering increased genetic gains and reducing the breeding cycles. This methodology requires inexpensive and sufficiently dense marker information to be successful, and with whole genome sequencing, it has become an important tool in many crops. The recent assembly of the pearl millet genome has made it possible to employ GS models to improve the selection procedure in pearl millet breeding programs. Here, three GS models were implemented and compared using …

Soil Health On A Small-Scale Sustainable Vegetable Farm In South Louisiana, Allison Guidroz

LSU Master's Theses

One of the biggest challenges facing the world today is the need to provide nutritious food to an ever-growing population in a way that does not compromise the ecosystem services of the soil that are necessary for life. The evidence for widespread degradation of the soil has been a major contributor in the increased interest in soil health. Most of the research in soil health has focused on field crops, which has led to a gap in the research of soil health on vegetable cropping systems. This objective of this study was to analyze the health of the soil on …

Horticultural Availability And Homeowner Preferences Drive Plant Diversity And Composition In Urban Yards, Jeannine Cavender-Bares, Josep Padullés Cubino, William D. Pearse, Sarah E. Hobbie, A. J. Lange, Sonja Knapp, Kristen C. Nelson

Ecology Center Publications

Understanding the factors that influence biodiversity in urban areas is important for informing management efforts aimed at enhancing the ecosystem services in urban settings and curbing the spread of invasive introduced species. We determined the ecological and socioeconomic factors that influence patterns of plant richness, phylogenetic diversity, and composition in 133 private household yards in the Minneapolis‐Saint Paul Metropolitan area, Minnesota, USA. We compared the composition of spontaneously occurring plant species and those planted by homeowners with composition in natural areas (at the Cedar Creek Ecosystem Science Reserve) and in the horticulture pool of species available from commercial growers. Yard …

Identifying Grazing-Driven Plant Indicators Of Rangeland Degradation In Semi Arid Zones Of Uzbekistan, Toshpulot F. Rajabov, Bakhtiyor K. Mardonov, Mahmud A. Muminov

IGC Proceedings (1997-2023)

The development of practical indicators of vegetation degradation is an important element in predicting and assessing rangeland health due to disturbances such as livestock grazing. Once established, phytoindicators provide a simple and visual operative way to diagnose active and possibly undesirable vegetation changes. This paper aimed to identify rapid, yet realistic and easily communicated plant indicators of rangeland degradation caused by intense grazing. The grazing gradient approach is applied to study plant traits affected by increased levels of grazing pressure. Qualitative and quantitative changes in key species of the plant community alongside successive changes of vegetation attributes along an apparent …

The Influence Of Geo-Morphological Landscape Patterns On Vegetation Characteristics In Tajikistan Grasslands, Mounir Louhaichi, Aziz Nubekov, Abdulla Madaminov, Barbara Rischkowsky

IGC Proceedings (1997-2023)

Grassland ecosystems are affected by a combination of physical and environmental factors, as well as by grazing and human induced activities. The primary objective of this study was to examine the influence of geo-morphological landscape patterns on vegetation characteristics in Tajikistan where two sites were selected. The vegetation sampling took place in spring and fall. Vegetation characteristics were assessed using the line intercept method for vegetation cover and species composition and quadrat sampling for biomass production. An ANOVA using replicated trials in complete block design was used to determine the relationship between aspect and vegetation characteristics. Treatments included location (site), …

Spatial Variability Of Soil Phosphorus In Grazing Systems, Mark Trotter, Warwick B. Badgery, Joshua Barron, Chris Guppy, Rebecca Haling, David Mitchell, Geoff Millar

IGC Proceedings (1997-2023)

Phosphorus (P) use efficiency has been identified as a key issue for Australian grazing systems. This project examined the spatial variability in soil P concentration from two separate surveys of grazed pasture fields. A field on the central tablelands of NSW had a range in Bray P of 1.2 to 140 mg/kg and a COV of 107%. The other field on the northern tablelands of NSW reported a range in Colwell P from 13.0 to 121.1 mg/kg and a COV of 59%. Maps of the spatial variability of soil P demonstrated that there is a relationship with field elevation. Application …

Monitoring Landscape Changes Using Remote Sensing Technology In Southern Africa, Anthony R. Palmer

IGC Proceedings (1997-2023)

Rangelands are a major global resource, and there is an urgency to improve the assessment of landscape performance to capture carbon, produce biomass, and improve water use. Effective monitoring necessitates the collection of high quality rangeland condition data using repeatable techniques. Despite much effort, there are few comprehensive data sets that allow confident detection of landscape change. Data are lacking for several reasons, including high cost of data collection, conflicting methodologies, and loss of archival data. Satellite imagery provides the basis for trend and pattern analysis of rangeland in different conditions classes and this paper presents some examples of the …

Alternative For Intensification Of Beef Production Under Grazing, Valéria P. B. Euclides, Kepler Euclides Filho, Denise B. Montagner, Geraldo Ramos Figueiredo, Flávia Da Conceição Lopes

IGC Proceedings (1997-2023)

One of the challenges to overcome in order to assure the position occupied by Brazil as one of the most important players in the world beef market is to design sustainable technological alternatives, which will maintain a constant uniform beef supply all year round. This crucial problem could be solved by using more intensively, the alternatives available for pastures management and feed supplement-ation. However, the potential results created by these strategies might be better explored by using the right choice of animals as far as genetic group and weaning weight is concerned. Thus, in order to fulfill this goal it …

Pasture Improvement Needs And Options For New Zealand Sheep And Beef Farms, Andy R. Bray, Tom J. Fraser, Warren Mcg. King, Alec D. Mackay, Derrick Moot, David R. Stevens

IGC Proceedings (1997-2023)

In recent years in New Zealand, sheep and beef farming has been outcompeted for prime land. This means that the government and industry targets to increase sheep and beef production have to be achieved on farms with significant constraints on pasture production. They are increasingly restricted to hilly and other locations with variable climates and soils, and landscape constraints on farming practices. Thus there are limits on the ability to improve pasture production – whether by pasture renewal or through means like grazing management, fertiliser use, or weed and pest control.

Improving Summer/Autumn Feed Quality In New Zealand Hill Country, Grant M. Rennie, Warren Mcg. King, Coby J. Hoogendoorn, Brian Devantier, Trevor L. Knight, Catherine Cameron

IGC Proceedings (1997-2023)

Pasture management in spring has a strong influence on pasture quality in summer and autumn in New Zealand hill country pastures. Manipulation of defoliation frequency and intensity during mid-late spring can impact summer and autumn pasture quality and quantity (Orr et al. 1988). Summer/autumn management is mainly concerned with maintaining herbage quality in summer wet areas and controlling animal pressure in summer dry areas for drought management and winter feed stocks (Clark 1994). Deferred grazing to transfer pasture growth from late spring into summer and autumn deficits is difficult due to detrimental effects on pasture quality, plant density and …