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Dilemma: Increase In Human Food Production Or Use Of Grasslands For Environmental And / Or Social Purposes, A. D. Meister Jan 2022

Dilemma: Increase In Human Food Production Or Use Of Grasslands For Environmental And / Or Social Purposes, A. D. Meister

IGC Proceedings (1977-2023)

In the title for this paper we find three major objectives: to feed the world, sustain the environment and provide resources for social purposes, and a dilemma. Even though the word ‘dilemma’ usually implies choice between undesirable alternatives, it is obvious that the alternatives here are not undesirable. Is the dilemma then, that we can only do one at the time, or that the consequences of favouring one over the other can lead to undesirable outcomes? It is my opinion that we are talking about the latter interpretation. It is the foreclosing of options by allowing one objective to dominate …


The Development And Prospect Of Chinese Grassland Economic System, Fuzeng H. Jan 2022

The Development And Prospect Of Chinese Grassland Economic System, Fuzeng H.

IGC Proceedings (1977-2023)

China is a country with an old agriculture civilization of the world. The arrangement of the crop and pasture area had developed from Han and Tang dynasty. (From A.C 206.to AD 907). Chinese livestock economic had undergone the winding development for a thousand years of feudal society, however, It still belong to a phase of the loose private ownership. From 1949 when The People's Republic of China was founded, the pasture was nationalized and collective management. Since 1980s, the planned economic changed into the market economic gradually. The pasture was public ownership, but management by contract, paid utilization and unchanged …


Contextual Factors In The Management Of Common Grazing Lands: Lessons From Mongolia And Northwestern China, R. Mearns Jan 2022

Contextual Factors In The Management Of Common Grazing Lands: Lessons From Mongolia And Northwestern China, R. Mearns

IGC Proceedings (1977-2023)

Seen in a global perspective, pastoral development is now increasingly motivated by social and environmental objectives rather than by production- or output-orientated objectives. Attention is shifting towards a broader concern with sustainability, both of grasslands, and of the livelihoods of those who rely on them (de Haan et al, 1997, Fratkin and Mearns forthcoming). Quite how these twin sustainability objectives may be achieved in particular contexts, however, is an empirical question. Drawing on examples from a diverse range of natural grassland-based livestock production systems under economic transition in Mongolia and northwestern China, this summary paper aims to show how an …


De-Intensification Of Grasslands: Understanding The Processes To Find The Balance, K. C. Hodgkinson Jan 2022

De-Intensification Of Grasslands: Understanding The Processes To Find The Balance, K. C. Hodgkinson

IGC Proceedings (1977-2023)

There is a growing trend in Australia and other developed countries for deintensification of animal production from grasslands and for grasslands to be used for purposes other than livestock grazing. These shifts are occurring for a variety of reasons including unsustainable land management practices, environmental pollution, loss of conservation value, poor commodity prices and declining rural infra-structure and communities. In Australia, the shifts are under way in agricultural grasslands, where sown pastures occur in a matrix of semi-natural woodlands, but less so in the other three major natural grasslands that forms the arid and semi-arid rangelands.

The conversion of natural …


De-Intensification Of Grasslands: Current State And Trends, Michael Duru, Bernard Hubert Jan 2022

De-Intensification Of Grasslands: Current State And Trends, Michael Duru, Bernard Hubert

IGC Proceedings (1977-2023)

De-intensified use of grasslands, and more generally of the livestock systems they support, has been triggered by a growing sensitivity of citizens to environmental quality (nitrogen) and quality of animal products, and by the warnings addressed to political authorities by scientists about the environmental consequences of economic imbalances (decreasing biodiversity, drop in soil fertility, greenhouse effect), and in particular of food overproduction in Europe.

From an ecological standpoint, grassland de-intensification must be envisaged whenever the techniques implemented disrupt resource sustainability. The grassland resource itself may be at risk when a rate of vegetation offtake by herbivores that is incompatible with …


Stylosanthes Scabra - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Stylosanthes Scabra - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia

Environmental Weed Risk Assessments

Introducing new plants to an area may have both positive and negative effects on the environment, economy and community. To minimise the negative environmental impact of introducing new agricultural species, DPIRD conducts a risk assessment procedure based on widely accepted scientific standards. This report assesses Shrubby stylo (Stylosanthes scabra). Shrubby stylo (Stylosanthes scabra) is a shrubby, perennial legume, erect to suberect, with strong, woody stems, usually densely hairy and viscid, making them sticky under hot, dry conditions. It is a widespread and variable species, originating from South America and the Caribbean (Sousa Costa and Ferreira 1984) with two ecotypes identified …


Stylosanthes Hamata - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Stylosanthes Hamata - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia

Environmental Weed Risk Assessments

Introducing new plants to an area may have both positive and negative effects on the environment, economy and community. To minimise the negative environmental impact of introducing new agricultural species, DPIRD conducts a risk assessment procedure based on widely accepted scientific standards. This report assesses Caribbean stylo (Stylosanthes hamata). Caribbean stylo (Stylosanthes hamata) is an annual or short-lived perennial herbaceous legume. Individual plants behave as self-regenerating annuals or biennials. In the Northern Territory up to 40% of plants persist from one wet season to the next (Cameron 2010), but this varies depending on the length of the dry season. It …


Review Of Spiders Of North America, By Sarah Rose, Michael L. Draney Jan 2022

Review Of Spiders Of North America, By Sarah Rose, Michael L. Draney

The Prairie Naturalist

A field guide to spiders, the dominant terrestrial predator group, has long been a desire for North American naturalists, biologists, and spider fans, but not surprisingly, the first “real” field guide has been a long time coming. The diversity of spiders, with over 50,000 known species globally (World Spider Catalog 2022) and around 4,000 in North America north of Mexico (Rose 2022), is well beyond the diversity of more traditional field guide targets such as birds (about 1,000 species north of Mexico; American Birding Association 2022) or butterflies (about 725 species north of Mexico; North American Butterfly Association 2022). Also, …


Review Of Methods For Ecological Research On Terrestrial Small Mammals, By Robert Mccleery, Lynda R. Lafond Jan 2022

Review Of Methods For Ecological Research On Terrestrial Small Mammals, By Robert Mccleery, Lynda R. Lafond

The Prairie Naturalist

Small mammals are used in ecological studies throughout the world, yet the subject has lacked a clear reference that included upto- date methods pertaining to passive detection, molecular, and statistical approaches. In Methods for Ecological Research on Terrestrial Small Mammals, McCleery and his coauthors build on previous research references (Braun 2005, Sutherland 2006, Krebs 2014, Silvy 2020) and present methodologies specific to the study of small mammals that are applicable globally. Written as an asset for novice and experienced small mammal researchers alike, Methods for Ecological Research on Terrestrial Small Mammals is organized in a logical format, providing readers …


Second Twenty-Five Year Index: Volumes 26–50, 1994–2018, Jane E. Austin Jan 2022

Second Twenty-Five Year Index: Volumes 26–50, 1994–2018, Jane E. Austin

The Prairie Naturalist

The first 50 years of the Prairie Naturalist reside on the shelves of libraries and personal collections. The articles and notes published over those years provide invaluable knowledge about Great Plains biota, communities, conservation, and landscape ecologies. Awareness of the wealth of information in those 50 print volumes has been limited, relying on references from other published papers or the limited number of articles that have been made available online by authors. This index serves as resource for individuals to digitally tap into the information published since 1994. This index, together with the first 25-year index, serves to complement the …


Cenchrus Ciliaris - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Cenchrus Ciliaris - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia

Environmental Weed Risk Assessments

Introducing new plants to an area may have both positive and negative effects on the environment, economy and community. To minimise the negative environmental impact of introducing new agricultural species, DPIRD conducts a risk assessment procedure based on widely accepted scientific standards. This report assesses Buffel grass (Cenchrus ciliaris). Buffel grass (Cenchrus ciliaris) is a perennial grass forming tufted tussocks to 1m which is native to large parts of Africa, Arabian Peninsula, western Asia, Middle East and the Indian sub-continent (Humphreys 1967). Seedheads form a dense, hairy cylindrical spike, with straw-coloured burrs or fascicles comprising 1-4 spikelets which are light …


Megathyrsus Maximus - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Megathyrsus Maximus - Environmental Weed Risk Assessment 2022, Department Of Primary Industries And Regional Development, Western Australia

Environmental Weed Risk Assessments

Introducing new plants to an area may have both positive and negative effects on the environment, economy and community. To minimise the negative environmental impact of introducing new agricultural species, DPIRD conducts a risk assessment procedure based on widely accepted scientific standards. This report assesses Panic grass (Megathyrsus maximus). Panic grass (Megathyrsus maximus) is a warm season (C4), perennial grass which is widely used in South America, Japan, India, and sub-tropical Queensland and more recently in the northern agricultural region of Western Australia. It is a productive forage grass for pasture, green-forage, hay and silage. The panic grasses are shade …


Modeling The Evolution Of Herbicide Resistance In Weed Species With A Complex Life Cycle, K. Harrison Holmes, John L. Lindquist, Richard Rebarber, Rodrigo Werle, Melinda K. Yerka, Brigitte Tenhumberg Jan 2022

Modeling The Evolution Of Herbicide Resistance In Weed Species With A Complex Life Cycle, K. Harrison Holmes, John L. Lindquist, Richard Rebarber, Rodrigo Werle, Melinda K. Yerka, Brigitte Tenhumberg

Brigitte Tenhumberg Papers

A growing number of weed species have evolved resistance to herbicides in recent years, which causes an immense financial burden to farmers. An increasingly popular method of weed control is the adoption of crops that are resistant to specific herbicides, which allows farmers to apply the herbicide during the growing season without harming the crop. If such crops are planted in the presence of closely related weed species, it is possible that resistance genes could transfer from the crop species to feral populations of the wild species via gene flow and become stably introgressed under ongoing selective pressure by the …


Invasion Of Plant Communities, Stephen L. Young, Sarah Kimball, Stephen J. Novak Jan 2022

Invasion Of Plant Communities, Stephen L. Young, Sarah Kimball, Stephen J. Novak

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Due to numerous human activities, organisms have been transported and either accidentally or deliberately introduced all around the globe. Biological invasions are now considered to be one of the main drivers of global change because many invasive plants have severe ecological, economic, and health consequences. Thus, there is an ever-growing need to better understand invasions to determine how specific plant species are able to establish in communities and, in many cases, expand their range. Here, we describe the invasion process and how it contributes to the invasion of plant communities. We present an invasion-factor framework (IFF) model that uses three …


Skeleton Weed Program 2021/22 : Annual Report To Grain Growers, Department Of Primary Industries And Regional Development, Western Australia Jan 2022

Skeleton Weed Program 2021/22 : Annual Report To Grain Growers, Department Of Primary Industries And Regional Development, Western Australia

Agriculture reports

No abstract provided.


Documenting The Rapidly Expanding Distribution Of Invasive Ravenna Grass (Tripidium Ravennae) Eastern In Kansas, Rachel A. Styers Jan 2022

Documenting The Rapidly Expanding Distribution Of Invasive Ravenna Grass (Tripidium Ravennae) Eastern In Kansas, Rachel A. Styers

Electronic Theses & Dissertations

Invasive species cause significant ecological losses in the United States where they cost approximately $21 billion dollars a year to manage (Fantle-Lepczyk et al., 2022). Early detection of new invasive species, coupled with a rapid response of management efforts, can help to slow the ecological and economic impacts caused by these habitat invaders. Tripidium ravennae (L.) H. Scholz (or Ravenna grass) is a tall, robust, cespitose grass known to occur in Kansas, although its distribution remained poorly documented prior to this study. Given its known invasive tendencies, it has been declared noxious in at least six US states. Coupled with …


Review Of The Duck Factory: A History Of Waterfowl In North Dakota, By Mike Jacobs And Erik Fritzell, Douglas Johnson Jan 2022

Review Of The Duck Factory: A History Of Waterfowl In North Dakota, By Mike Jacobs And Erik Fritzell, Douglas Johnson

The Prairie Naturalist

It was by geological accident that North Dakota became the heart of duck production in the continental United States. When the Wisconsin glaciation retreated some 11,000 years ago, it left an uneven layer of glacial till over much of North Dakota and nearby states and provinces, an area termed the Prairie Pothole Region. Large blocks of ice in the glacial till eventually melted and formed depressions that became wetlands, or prairie potholes. These were embedded in a matrix of soil that, with millennia of growth by deep-rooted prairie plants, became rich topsoil. The wetlands, surrounded by luxuriant grassland, were ideal …


Review Of Loon Lessons: Uncommon Encounters With The Great Northern Diver, By James D. Paruk, Kristin Bianchini Jan 2022

Review Of Loon Lessons: Uncommon Encounters With The Great Northern Diver, By James D. Paruk, Kristin Bianchini

The Prairie Naturalist

Gavia immer Brunnich (Common Loon) is a bird that has captivated bird watchers, wildlife enthusiasts, campers, cottagers, and others interested in the natural world for centuries. The loon also features prominently in Native American mythology. For many, the loon symbolizes the wildness of the north, and it is often used as a sentinel of lake health. Indeed, the Common Loon has inspired a wealth of literature, both scientific and popular, describing this species’ ecology, behavior, and fitness in the face of environmental changes. To this literature, Loon Lessons: Uncommon Encounters with the Great Northern Diver adds a complete and accurate …


Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko Dec 2021

Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko

IGC Proceedings (1977-2023)

The aim of the present paper was to study alterations of the grassland flora from 55 plots following a more extensive management under long term observation within 6 years. Extensification of grassland use leads to an increase of the numbers of plant species by 32%, “Red-list-species” included. The moisture number of the soils slightly increased and the reaction and nitrogen numbers decreased. Results are presented for different vegetation units.


Influence Of Extensive Management On Botanical Composition Of Permanent Meadow Sward, K. Mlynarczyk, E. Korona, E. Marks Dec 2021

Influence Of Extensive Management On Botanical Composition Of Permanent Meadow Sward, K. Mlynarczyk, E. Korona, E. Marks

IGC Proceedings (1977-2023)

The aim of undertaken investigations was to find the possibilities of grassland management with special respect to the biodiversity and the landscape conservation. Changes in botanical composition of the meadow sward against a background of different mowing utilization were examined on the semi-natural meadows situated on the peat-mursh soil in Masurian Landscape Park (north-east Poland). The areas mown with biennial pause and completely turned off from uses followed gradual simplifying of species composition and increasing of bog species participation. Results show on advisability of passing one harvest each year or with one-year pauses.


Vegetation Changes In Sown Grassland In The Uk After Nine Years Of Extensive Grazing Management, C. A. Marriott, G. T. Barthram Dec 2021

Vegetation Changes In Sown Grassland In The Uk After Nine Years Of Extensive Grazing Management, C. A. Marriott, G. T. Barthram

IGC Proceedings (1977-2023)

The effect of extensive grazing management with sheep on vegetation change in sown pastures (initially containing Lolium perenne and Trifolium repens) in the uplands of Scotland was investigated from 1990-1999. One treatment was representative of current more intensive management systems; it was fertilized, and maintained at a sward surface height of 4 cm. Two treatments were unfertilized and were maintained at sward surface heights of 4 cm or 8 cm; the ewe numbers carried on these treatments averaged 74% and 44%, respectively, of those on the fertilized treatment. In all treatments the sheep were Scottish Blackface ewes. Their single …


The Influence Of Rising Atmospheric Co2 On Grassland Ecosystems, J. A. Morgan, P. C. D. Newton, J. Nösberger, C. E. Owensby Dec 2021

The Influence Of Rising Atmospheric Co2 On Grassland Ecosystems, J. A. Morgan, P. C. D. Newton, J. Nösberger, C. E. Owensby

IGC Proceedings (1977-2023)

Increasing atmospheric CO2 concentrations and climatic change will have significant effects on the ecology of grasslands. This paper evaluates results from four CO2 enrichment studies in contrasting grasslands. A Swiss study investigates the effects of elevated CO2 (600 μL L-1 CO2) on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L), a New Zealand study examines how elevated CO2 (475 μL L-1 CO2) affects a botanically diverse pasture, and studies in the Kansas tallgrass prairie and the Colorado shortgrass steppe investigate the effects of an approximate …


Elevated Co2 Enhances Productivity And The C/N Ratio Of Grasses In The Colorado Shortgrass Steppe, J. A. Morgan, A. R. Mosier, D. R. Lecain, W. J. Parton, D. G. Milchunas Dec 2021

Elevated Co2 Enhances Productivity And The C/N Ratio Of Grasses In The Colorado Shortgrass Steppe, J. A. Morgan, A. R. Mosier, D. R. Lecain, W. J. Parton, D. G. Milchunas

IGC Proceedings (1977-2023)

Atmospheric CO2 concentrations have been increasing since the industrial revolution, and are projected to double within this century over today's concentration of 360 µmol mol-1 . This study used six open-top chambers in the Colorado, USA shortgrass steppe to investigate how increasing CO2 will affect productivity and C and N status of indigenous perennial grasses and forbs. From March until October, chambers were placed on two plots in each of the three blocks. In each block, one chamber was assigned an ambient CO2 treatment (~360 µmol mol-1), the other an elevated CO2 treatment …


Rangeland Desertification In China, Wang Tao Dec 2021

Rangeland Desertification In China, Wang Tao

IGC Proceedings (1977-2023)

Land desertification is one of the most serious environmental and social-economic problems in the North China. The processes of desertification mainly have being controlled by the interaction of human activities and fragile eco-environment, that means the pattern and intension of landuse are major factors for development or reverse of desertification. Because of the increasing pressure of population, the rangeland in the North China has being cultivated decade by decade, which changed landuse from grassing to cropping in a large area and destroyed the natural vegetation cover. The result is to let the wind erosion become easier and the desertification has …


Grasslands, Communicating The Benefits, D. Keeney Dec 2021

Grasslands, Communicating The Benefits, D. Keeney

IGC Proceedings (1977-2023)

The multiple benefits of perennial agriculture , including forages and grasslands, for building soil quality, protection of natural resources, enhancement of biodiversity and wildlife, are well known to us, but little understood by the public. This is not a situation where “more education” would necessarily increase recognition. Rather, we must build in the public a desire for the enhancement of green space, clean water and air, and diverse landscapes that multiple purpose agriculture can bring. We seek such environments intuitively and now that much of the world’s people are “trapped” in urban settings of steel and concrete, this desire is …


Agropastoral Systems An Alternative To Revert Pasture Degradation In The Cerrados Of Brazil: Preliminary Results, Manuel C. M. Macedo, J. A. M. Bono, A. H. Zimmer, F. P. Costa, Tsutomu Kanno, Cesar Heraclides Behling Miranda, A. N. Kichel Dec 2021

Agropastoral Systems An Alternative To Revert Pasture Degradation In The Cerrados Of Brazil: Preliminary Results, Manuel C. M. Macedo, J. A. M. Bono, A. H. Zimmer, F. P. Costa, Tsutomu Kanno, Cesar Heraclides Behling Miranda, A. N. Kichel

IGC Proceedings (1977-2023)

A long term experiment was set to test the hypothesis that agropastoral systems could improve crop and animal production, being more profitable and sustainable relative to economical, biological and environmental aspects, than continuous and traditional crop and grazing pasture systems. Five farming systems are being tested: two traditional (continuous soybean annual cropping and continuous pasture cropping) and three agropastoral systems (two combinations of four by four years of rotational crop-pasture systems and one by three years of crop-pasture rotation). Animal production in continuous pasture cropping measured as liveweight gain/ha (LWG) are declining along the years in the sub-treatment without fertilizer …


Evaluation Of A Number Of Grass Species For Restoring Degraded Semi-Arid Rangelands In Southern Africa, K. Kellner, S. De Wet Dec 2021

Evaluation Of A Number Of Grass Species For Restoring Degraded Semi-Arid Rangelands In Southern Africa, K. Kellner, S. De Wet

IGC Proceedings (1977-2023)

The biophysical environment is an important determinant of land degradation in both commercial and communal land tenure systems in South Africa. According to a recent study on the status of land degradation, approximately 25% of the total land cover in South Africa is degraded. Several technologies exist to restore the soil and vegetation degraded areas in natural pastures. To improve the production and biodiversity potential for agricultural and conservation uses in these rangelands, a common restoration technology includes the cultivation the eroded and compacted soil surfaces by rip- ploughing and the re-vegetation with high productive, palatable and perennial species. Five …


Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman Dec 2021

Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman

IGC Proceedings (1977-2023)

The objective of this study was to determine the impact of rangeland in different botanical composition classes (good, moderate and poor), on water-use efficiency (WUE: crude protein produced per unit of evapotranspiration) and soilwater content. The same measurements were also made on an undisturbed bare soil surface and soil cultivated twice per annum. Evapotranspiration was determined by quantifying the soil-water balance equation with the aid of runoff plots and soil-water content measurements done by a neutron hydroprobe. Water-use efficiency declined significantly (P ≤ 0.01) with rangeland degradation. Rangeland in good condition averaged a WUE of 0.28 kg crude protein ha …


Community Structure Of Serrated Tussock (Nassella Trichotoma) Infested Grasslands, Warwick B. Badgery, David R. Kemp, D. L. Michalk, W. Mcg. King Dec 2021

Community Structure Of Serrated Tussock (Nassella Trichotoma) Infested Grasslands, Warwick B. Badgery, David R. Kemp, D. L. Michalk, W. Mcg. King

IGC Proceedings (1977-2023)

Serrated tussock (Nassella trichotoma) is the most serious perennial grass weed in southeastern Australia, extending over more than a million hectares. Previous control techniques using herbicides and oversowing with competitive pastures are no longer feasible in many of the lower fertility, infested areas. New management solutions need to be found, based upon a better understanding of the ecology of this species. A survey was done to determine the community structure of serrated tussock infested grasslands. Winter growing C3 grasses were closely associated with serrated tussock, while C4 perennial grasses appeared not to be. It is not known if …


Valuing The Pasture Resource - Importance Of Perennials In Higher Rainfall Regions Of South Eastern Australia, P. M. Dowling, R. E. Jones, David R. Kemp, D. L. Michalk Dec 2021

Valuing The Pasture Resource - Importance Of Perennials In Higher Rainfall Regions Of South Eastern Australia, P. M. Dowling, R. E. Jones, David R. Kemp, D. L. Michalk

IGC Proceedings (1977-2023)

The premature decline of perennial grass based pastures in southern temperate Australia results in poor productivity and unstable pastures that allow invasion by less desirable weedy species and the potential for soil degradation. The loss of perennial species is attributed to overgrazing arising from an undervaluation of the pasture resource. Resowing pastures is largely uneconomic so maintenance of, or increasing the perennial, is dependent on improved grazing and pasture management practices. A key to changing perceptions is valuing the true worth of the perennial component. Results are presented from a model that takes into account the seasonality of production of …