Physical Sciences and Mathematics Commons^™

Modelling Catchment-Scale Evapotranspiration And Net Primary Production In Sub-Humid African Grasslands: Towards Understanding Carbon And Water Trade-Offs In Communal Rangelands, A. R. Palmer, Z. Munch, L. Vermeulen

IGC Proceedings (1993-2023)

Being able to confidently predict net primary production within intensively used rangeland systems has become the goal of many rangeland scientists. The communally-managed rangelands of Africa, with their very high livestock numbers, represent such a challenge, as above-ground biomass is most often depleted before it has had chance to accumulate. In order to provide more accurate estimates of NPP for these rangelands, we explored the use of direct measurements of canopy cover, standing biomass and leaf area index, against standard vegetation indices from the Sentinel 2 sensors. Following intensive field surveys, we developed regression models of the relationships between Sentinel …

Lowveld Savanna Bush Cutting Alters Tree-Grass Interactions, E. R. Wedel, J. B. Nippert, A. M. Swemmer

IGC Proceedings (1993-2023)

Savannas are characterized by the coexistence of trees and grasses, and their interactions are modified by water availability and herbivore activity. Many savannas are experiencing bush encroachment, resulting in reduced herbaceous productivity and shifts in savanna structure. This study aims to understand the effects of tree density and tree cutting on herbaceous productivity, water use, and herbivore abundance in a mopane-dominated lowveld savanna. We present data from a 4-year mopane-cutting experiment in the Mthimkhulu Game Reserve bordering Kruger National Park (South Africa). We established three 60x60 m plots for experimental manipulation where mopane stems and re-sprouting shoots were cut 2-3 …

Multifunctionality Of Sown Grassland Is Enhanced By Combining Four Complementary Species, M. Suter, O. Huguenin-Elie, Andreas Lüscher

IGC Proceedings (1993-2023)

We investigated species diversity effects and multifunctionality in an intensively managed grassland. A diversity experiment was set up with monocultures and mixtures comprising Lolium perenne, Dactylis glomerata, Trifolium pratense, and Trifolium repens, and was maintained for three years at 150 kg∙N∙ha^-1∙ year^-1. Ten functions were measured that represented i) forage production (aboveground biomass yield (μ), standard deviation of yield (σ), temporal stability (μ/σ), weed biomass), ii) N cycling (symbiotic-N₂-fixation, N efficiency, NO₃ in soil solution), and forage quality (crude protein content (CP), organic matter digestibility …

Status And Distribution Of Range Plants Genetic Resources In Al Sabaloga Biosphere Conservation Area, Sudan, Salma Abdelghaffar Hassan Alamin, Hala Ahamed Hassan

IGC Proceedings (1993-2023)

The study was conducted in the Al Sabaloga area in 2017. The objective of this study was to investigate the status and distribution of range plants genetic resources in the study area. Sample size of 131 was chosen randomly to collect primary data. The data were coded, summarized, tabulated and processed. Analysis was conducted using (SPSS) computer program. The results were presented in the form of a frequency distribution. The result of this study represented in an ecological zone in the study area about (67%) Nile bank and island, Goz (35%), Valley (22%), Plains (17%) and Mountains (17%). For example, …

Rejuvenation Of Rangelands – Role Of Diversity And Improvement Strategies Of Range Grasses, A. K. Roy, D. R. Malaviya, P. Kaushal

IGC Proceedings (1993-2023)

In India, a major part of the rural economy is dependent on the grazing-based livestock husbandry which is unique integration of agriculture and livestock coupled with rich traditional knowledge. Ecosystems of common property resources had been a mainstay in rural economy and livelihood. The traditional grazing forage resources in arid and semi-arid regions have deteriorated a lot due to various factors including heavy grazing pressure, climate change and dominance of invasive species, thus, needs rejuvenation. Additionally, these are causing serious economic and ecological problems such as poor productivity, soil and water erosion and reduced carbon sequestration.

The genetic improvement of …

Soil Carbon Stocks Are Stable Under New Zealand Hill Country Pastures With Contrasting Phosphorus And Sheep Stocking Regimes, Ronaldo Vibart, Alec D. Mackay, C. Mckenzie, Brian Devantier, Des A. Costall, E. Noakes, F. Bilotto

IGC Proceedings (1993-2023)

A temporal and spatial assessment is required to quantify the effects of nutrient inputs and varying grazing management regimes on soil organic carbon (SOC) stocks under grazed pastures in complex landscapes. We examined SOC stocks under permanent pastures in three farmlets under a range of different annual phosphorus (P) fertiliser and associated sheep stocking regimes. The farmlets examined had either no annual P applied (NF), 125 kg single superphosphate (SSP) ha^-1 (LF), or 375 kg SSP ha^-1 (HF) on an annual basis since 1980. Soils were sampled to three depths (0-75, 75-150, 150-300 mm) in 2003 and 2020, …

Soil Organic Carbon And Total Nitrogen Stock Response To Traditional Enclosure Management In Eastern Ethiopia, Mohammed Abdulahi, Abule Ebro, Lisanework Nigatu

IGC Proceedings (1993-2023)

Traditional enclosures are widely used by pastoralists in East Africa. However, the response of basic soil properties to the establishment of traditional enclosure management remains poorly understood. The aim of this study was to investigate the impacts of traditional enclosure on soil organic carbon and total nitrogen stock in the Bordade rangelands, eastern Ethiopia. Soil samples were collected from twelve area enclosures and openly grazed areas at a depth of 0-30 cm. The samples were analyzed for soil organic carbon, total nitrogen and bulk density. There were significant differences between enclosure and openly grazed areas in soil organic carbon and …

Recent Advances In Wearable Sensing Technologies, Alfredo J. Perez, Sherali Zeadally

Information Science Faculty Publications

Wearable sensing technologies are having a worldwide impact on the creation of novel business opportunities and application services that are benefiting the common citizen. By using these technologies, people have transformed the way they live, interact with each other and their surroundings, their daily routines, and how they monitor their health conditions. We review recent advances in the area of wearable sensing technologies, focusing on aspects such as sensor technologies, communication infrastructures, service infrastructures, security, and privacy. We also review the use of consumer wearables during the coronavirus disease 19 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus …

Influence Of Seasonality And Agricultural Practices On Soil Microbes In Kamishihoro, Japan, Y. Madegwa, Y. Uchida

IGC Proceedings (1993-2023)

Soil microbes are important for maintenance of soil fertility and ecosystem functions. Agricultural practices such as land use, seasonality and fertilizer application effect the soil microbial community structure. However, the effect of these management practices on soil microbes and related functions, especially in one specific region, is still not clear.

Therefore, the study was conducted in Kamishihoro, Japan, to determine effect of land use (cropland, grassland), season (summer, spring) and fertilizer (anaerobic digestate, control) on soil microbial community and functions. Experimental procedure included DNA extraction, quantification, purification, amplification of 16SrRNA (bacterial gene) and Next Generation Sequencing (Ion PGM). Data analysis …

Hydraulic Responses Of Shrubs And Grasses To Fire Frequency And Drought In A Tallgrass Prairie Experiencing Bush Encroachment, K. O’Keefe, R. Keen, E. Tooley, S. Bachle, J. B. Nippert, K. Mcculloh

IGC Proceedings (1993-2023)

The increase in abundance and density of woody plants in herbaceous ecosystems (i.e. bush encroachment) is occurring globally and is driven by reduced fire frequency, climate change, and the utilization of deeper, more reliable soil water by woody plants. Thus, a comprehensive understanding of the physiological processes through which woody and herbaceous plants use water will provide greater insight into the mechanisms of bush encroachment, as well as the trajectory of encroachment in a changing climate. Our objective was to assess how experimental changes in water availability and fire frequency impact belowground water-use traits in Cornus drummondii, the primary …

Fighting Wildfire With Prescribed Fire In The Southern Great Plains, Usa: Liability, Regulatory And Social Factors, Urs P. Kreuter, M. L. Treadwell, C. L. Wonkka, D. Toledo, D. L. Stroman, D. Twidwell

IGC Proceedings (1993-2023)

Elevated fuel loads together with hotter and drier climatic conditions are expected to produce more frequent catastrophic wildfires in rangelands. This has led to calls for more prescribed fire to reduce fuel loads. However, perceptions that prescribed fire presents substantial legal liability risks hinder its use by landowners. Here we present research findings about the perceptions of landowners, county commissioners and district court judges regarding prescribed fire in the Southern Great Plains. The extent of liability incorporated in legal statutes pertaining to prescribed fire can affect the use of this land management tool, and the enactment of burn bans by …

Indian Forage Scenario – Region Wise Availability And Deficit, A. K. Roy, Rajiv K. Agrawal, N. R. Bhardwaj, Asim Kumar Misra, S. K. Mahanta

IGC Proceedings (1993-2023)

In India, rapid urbanisation, changing food habit and higher purchasing power have increased the demand for animal based food products.Proper feeding strategies using green nutritious fodderis key to increase livestock production and productivity in economical and sustainable way.Three major sources of fodder are crop residues, cultivated fodder from arable land (irrigated and rainfed) and fodder from common property resources like forests, permanent pastures, grazing lands, cultivated wasteland, fallow lands etc.

Based on the livestock census, we estimated the green and dry fodder availability vis-a-vis demand and emerging deficit/surplus situation. The state wise livestock population for Cattle, Buffaloes, Goat, Sheep, Yak …

Pre- And Post-Degradation Management Of Rangelands: Implications For Sustainable Management, S. K. Tuffa, A. C. Treydte

IGC Proceedings (1993-2023)

Rangeland degradation directly affects livestock production, resulting in food insecurity and ecological instability. A shift in vegetation from grass to woody plants has severely affected cattle production in Ethiopian rangelands. Those grass species that are perceived by the pastoralists as highly palatable and desirable are currently decreasing in both quality and quantity. A reason for this decline has been claimed to be degradation owing to overgrazing and climate change. While appropriate management of livestock density in rangelands is essential for sustainable production and grassland ecosystem health, the management of dryland ecosystems is mired in controversy due to the complexity of …

Grólind – Sustainable Land Use Based On Ecological Knowledge, B. Marteinsdóttir, E. F. Þórarinsdóttir, G. Halldórsson, J. H. Stefánsson, J. Þórsson, K. Svavarsdóttir, R. Finnsdóttir, S. Jónsdóttir

IGC Proceedings (1993-2023)

The highlands of Iceland play an important role as summer rangelands for sheep. Large areas are badly degraded and the sustainability of this practice has been questioned. To achieve sustainable land management it is necessary both to obtain data on ecosystem changes over time and to ensure that the results are used by land users and policy makers in their management plans.

Currently, the first long-term national vegetation and soil monitoring programme (GróLind) is being developed in Iceland. The programme is based on an agreement between the Icelandic National Associations of Sheep Farmers, the Farmers Association of Iceland, Ministry of …

Grasses And Ruminants That Will Help Save Space Ship Earth, A. M. Craig, L. L. Blythe

IGC Proceedings (1993-2023)

For the last twenty years, it has been known that grasses are capable of extracting toxins from the soil. More recently, it has been shown that microorganisms from ruminants, especially sheep, can biodegrade certain toxins in plants and soil, including munition residues. The combination of these two processes act as an agricultural means to clear toxins and munitions from land has been termed Phyto-Ruminal-Bioremediation by the United States Department of Agriculture (USDA) as illustrated in the discussion below. As an example, plants containing toxins such as pyrrolizidine alkaloids can be cleared from pastures using sheep and their ruminant microorganisms. Use …

Mongolian Rangelands Have A Great Potential For Natural Recovery, Bulgamaa Densambuu, Sumjidmaa Sainnemekh, Brandon T. Bestelmeyer, Budbaatar Ulambayar, Burmaa Dashbal, Erdenetsetseg Baasandai

IGC Proceedings (1993-2023)

Mongolians are aware that rangeland degradation is accelerating due to the combination of unsustainable use and drought events, but the natural recovery of degraded rangeland and timelines for recovery are less well studied. In this paper, we describe the use of “recovery class” concepts in rangeland classification that are being used to evaluate rangeland condition and management impacts across Mongolia. Recovery classes are analogous to degradation classes already used in Mongolia, but are based on ecological site descriptions (ESDs) and provide information about expected recovery rates based on quantitative measurements. While the degradation levels communicate the severity of plant community …

Livestock Corridors Working As Pollinator Refuges And Dispersal Hotspots: Lessons From Spain, P. Manzano, A. García-Fernández, J. Seoane, F. M. Azcárate, J. M. Iriondo, B. Peco

IGC Proceedings (1993-2023)

Habitat fragmentation is one of the greatest threats to biodiversity conservation and ecosystem productivity mediated by direct human impact. Its consequences include genetic depauperation, comprising phenomena such as inbreeding depression or reduction in genetic diversity. While the capacity of wild and domestic herbivores to sustain long-distance seed dispersal has been proven, the impact of herbivore corridors in plant population genetics has not been observed previously.

We conducted this study in the Conquense Drove Road in Spain, where sustained use by livestock over centuries has involved transhumant herds passing twice a year en route to winter and summer pastures. We compared …

Choosy Grazers And Plant Communities – Interactions Between Cattle Breeds And Vegetation In Semi-Natural Pastures, C. M. Pauler, Johannes Isselstein, J. Berard, T. Braunbeck, M. K. Schneider

IGC Proceedings (1993-2023)

It is well recognized that domesticated and wild ruminant grazers have an important impact on the composition of grassland vegetation, mainly by forage selection, trampling and defaecation. However, little is known on the effects of genetic diversity, for example differences among breeds of cattle. Cattle breeds differ in terms of robustness, growth rate, weight and probably also in movement and forage selection behaviour, which all could impact vegetation composition. Our study therefore aimed at identifying breed-specific differences in forage selection and behaviour and its consequences for vegetation. In a controlled experiment on semi-natural pastures in the Swiss Alps, suckler cows …

Germinable Soil Seed Bank Of Bothriochloa Macra Dominated Pasture In South-Eastern Australia, M. L. Mitchell, J. M. Virgona, A. Durling, F. W. Dempsey

IGC Proceedings (1993-2023)

In native pastures, soil seed banks play an important role in conserving the genetic material in a plant population, influencing community structure and providing protection against adverse climatic conditions. One important native grass is Bothrichloa macra (Steud.) S.T.Blake (Red grass, Red-leg grass). This grass is a C₄ indigenous perennial grass that is commonly found in native pastures in the high rainfall zone of south-eastern Australia.

At Tarrawingee, NE Victoria, (36°25´S, 146°31´E) and Wymah, southern NSW, (35°58´S, 147°11´E), Australia, two sites that had Bothriochloa macra as the dominant native grass were sampled. Three hundred cores (50 mm diameter and 50 …

Carbon And Nitrogen Pools In Soil Aggregates Were Affected By Grazing Component ---- Results From Dry And Wet Sieving Methods, N. Liu, Y. Q. Wei, Y. Pang, B. Wei, Y. J. Zhang

IGC Proceedings (1993-2023)

Grazing intensity can affect soil carbon (C) sequestration in semiarid grassland, but less is known about the effects of grazing component (defoliation, trampling, excreta return and their combinations) on the C and Nitrogen (N) in soil aggregates. In this study, a simulated grazing experiment was established in a typical steppe of Inner Mongolia, and we investigated the impacts of different grazing component treatments on the different size of aggregates distribution and their C and N content from dry and wet physical separations. Different soil C fractions were showed in different sieving method. The C content of different aggregate size showed …

Rangeland Rehydration: Collaboration Between Land Managers, Government And Private Experts, P. Theakston, H. J. R. Pringle, L. Mashford

IGC Proceedings (1993-2023)

In the rangelands of New South Wales, Australia, many successful soil erosion control techniques have been developed. These techniques have been implemented by the Western Local Land Services (WLLS), rehabilitating 23,000 ha since 2004. However the focus was on degraded land with little regard to catchment dynamics and the threatening processes that were causing the degradation.

With the introduction of Ecosystem Management Understanding (EMU)™ in 2016, the focus was broadened to address grazing properties in a drainage ecosystem context. There is a focus on understanding landscape function and designing projects that address threatening processes.

With the integration of the WLLS …

Plant Root Mass Fraction Response To Soil Resource Limitation In The Context Of Dry Mediterranean Rangeland, Guy Dovrat

IGC Proceedings (1993-2023)

Root mass fraction (RMF) was proposed as a stable measurement of plant resource partitioning that can represent plant acquisition–conservation trade‐offs. We examined the effects of soil resources availability on RMF of abundant annual plant species of water-limited rangeland. We used data from controlled experiments in which nine species were grown under variable water and nitrogen availabilities and their root and shoot biomass were examined at flowering time. In legumes we examined also presence of N₂-fixation. In all of the species, reduced water and/or nitrogen availability was associated with increased RMF. However, the magnitude of variation in RMF found …

Climate Variability In The Woodbush Granite Grasslands Of South Africa: Effects On Grassland Diversity, M. Muller, F. Siebert, A. Linstädter, D. I. Thompson, S. J. Siebert

IGC Proceedings (1993-2023)

South African old-growth grasslands are hyper-diverse ecosystems which evolved under naturally occurring rainfall variability. It is predicted that future precipitation patterns will become more variable, which could lead to increased frequencies of extreme and prolonged drought events. This study aimed to investigate the effects of climate variability on plant diversity of the fragmented pristine, mistbelt grasslands of the Woodbush Granite Grasslands (WGG) at Haenertsburg, South Africa. It has been reported that species composition has changed substantially in this area, as disturbance-tolerant species enter these systems or existing competitor species become more dominant. A Temporal Beta-diversity Index (TBI) was used to …

Effects Of Thinning Density On Soil Water Content Of Alfalfa And David Peach Intercropping In The Hilly Loess Plateau, China, Z. X. Chen, X. L. Yang, G. H. Wang, Yuying Shen

IGC Proceedings (1993-2023)

Intercropping alfalfa (Medicago sativa) between the four meters inter-row spacing of David peach (Amygdalus davidiana) is one of replantation practices at the Longtan catchment in Gansu province of the western Loess Plateau in the early 1980’s. However, both alfalfa and David peach are deep-rooted species and their intercropping results in excessive consumption of soil water in the hilly Loess Plateau. To alleviate this, we set up four density/intercrop treatments, which includes: David peach+alfalfa (PA), David peach (P), 60% David peach+alfalfa (60% P+A) and 60% David peach (60% P). TRIME was used to quantify the soil water …

Exploring Drivers Of Invasiveness Of The Plant Species Senna Obtusifolia In Rangelands To Secure Forage Production In West Africa, O. Ouédraogo, A. Zaré, C. Bougma, S. Kambou, A. Linstädter

IGC Proceedings (1993-2023)

Rangelands in Sahelian countries are continuously over-grazed decreasing forage resources and causing rapid environmental changes. Senna obtusifolia is a less palatable plant species that becomes increasingly invasive. This research explored drivers of its invasiveness in the perspective to propose solutions to secure forage production in the pastoral reserves. Species composition and herbaceous aboveground biomass were assessed in rangelands with different levels of invasion of Senna obtusifolia along a climatic and land-use pressure gradient. A greenhouse experiment was conducted to test the competitiveness of this species. The development of Senna obtusifolia in rangelands affected significantly forage quantity. Indeed the biomass of …

Enhanced Grazing Management Assessment Using Drone-Based Lidar Measurements, V. W. Temu, W. C. Hession, P. Sforza, H. Wang

IGC Proceedings (1993-2023)

Globally, there is an urgent need of research-based technologies for small ruminant producers to benefit from rapidly growing market demands for ruminant meat and related food products from forage-based operations. However, effective forage-based animal production requires a rapid assessment, and monitoring of grazing management needs to adjust stocking rates and/or spatial animal distribution in a timely manner. Applicability of unmanned aerial vehicles (drones) for grazing management offers opportunities to rapidly estimate biomass build-ups, ground coverage, and monitor animal behaviour. The reliability of drone-based laser scanning (DLS) for monitoring warm-season grass responses to simulated grazing intensities was assessed at Virginia State …

Effects Of Parthenium Hysterophorus On Grassland Community In Nyando Sub-County, Kisumu County, Kenya, B. M. Mutua, W. Chiuri

IGC Proceedings (1993-2023)

Parthenium hysterophorus is an invasive alien species native to South and Central America. The plant is ranked as one of the most dreaded weeds of the world. Parthenium hysterophorus affects grassland community through the release of allelochemicals that inhibit the germination and growth of grass species. However, little is known about its effects on native grassland community in Nyando sub-county of Kenya. Therefore, this study sought to investigate the effects of P. hysterophorus on grass species, livestock production and its control. A total of 121 farm household heads were interviewed using semi-structured interview schedules. Descriptive analysis and the T-test at …

Ecorestore: Decision Support System To Restore The Productivity Of Degraded Rangelands In Southern Africa, Klaus Kellner, Dirk Pretorius, C. Marais

IGC Proceedings (1993-2023)

Land degradation is a multifaceted problem that affects the agricultural productivity of land due to a loss of vegetation cover and can often be ascribed to bush encroachment in savanna and grassland rangelands. Bush encroachment entails the increase in abundance and density of indigenous and alien woody vegetation (i.e. shrub thickening), which has a negative impact on the tree-grass ratio, biodiversity, as well as on a range of ecosystem services that affect the well-being of land users, often causing an increase in poverty and the introduction of non-sustainable land management practices, especially in arid- and semi-arid regions mostly affected by …

Rangeland Management In A Changing World – Active And Passive Restoration Case Studies From Ethiopia, Tanzania, And South Africa, A. C. Treydte, S. A. Baumgartner, S. K. Tuffa, A. A. Abdeta

IGC Proceedings (1993-2023)

Rangelands cover almost 50% of the earth’s land surface and are often found in marginal areas that often face climate extremes. The production of herbaceous biomass has strongly declined over the last decades due to overgrazing and adverse climatic conditions such as frequent droughts and flooding. While different rangeland restoration methods are being used, their effect on vegetation quality and quantity over time has rarely been experimentally tested and monitored. Our research comprises experiments of various rangeland restoration tools we have used across eastern and southern Africa. We conducted passive restoration through exclosure experiments and compared vegetation in and outside …

Counteracting Green Alder Shrub Expansion By Low-Input Grazing, M. K. Schneider, T. Zehnder, J. Berard, C. Pauler, M. Staudinger, Michael Kreuzer, A. Lüscher

IGC Proceedings (1993-2023)

In the past decades, the decline of traditional agriculture has caused an abandonment of marginal pastures in many mountain areas of Europe. In the Swiss Alps, green alder (Alnus viridis) is the most abundant successional shrub. A survey of 24 pasture-shrub gradients showed that the encroachment by green alder, in contrast to other shrubs, is associated with a substantial decline in plant species richness. The understorey of alder is primarily populated by very few, broad-leaved herbaceous species benefitting from the atmospheric nitrogen fixed by actinomycetes in symbiosis with green alder. However, the understory vegetation also provides an underestimated …