Sample records for rangeland plant
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Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems
Directory of Open Access Journals (Sweden)
Romeu de Souza Werner
Full Text Available ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense of Brazil. The treatments, which included mowed natural rangeland (NR, burned natural rangeland (BR, natural rangeland improved through the introduction of plant species after harrowing (IH, and natural rangeland improved through the introduction of plant species after chisel plowing (IC, were evaluated in a Nitossolo Bruno (Nitisol. In the improved treatments, soil acidity was corrected, phosphate fertilizer was applied, and intercropped annual ryegrass (Lolium multiflorum, velvet grass (Holcus lanatus, and white clover (Trifolium repens were sown. Management systems with harrowed or chisel plowed soil showed improved soil physical properties; however, the effect decreased over time and values approached those of burned and mowed natural rangelands. Natural rangeland systems in the establishment phase had little influence on soil organic C. The mowed natural rangeland and improved natural rangeland exhibited greater production of grazing material, while burning the field decreased production and increased the proportion of weeds. Improvement of the natural rangelands increased leguminous biomass for pasture.
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Plant/life form considerations in the rangeland hydrology and erosion model (RHEM)
Resilience of rangeland to erosion has largely been attributed to adequate plant cover; however, plant life/growth form, and individual species presence can have a dramatic effect on hydrologic and erosion dynamics on rangelands. Plant life/growth form refers to genetic tendency of a plant to grow i...
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Invasive Plants on Rangelands: a Global Threat
Invasive plant species are spreading and invading rangelands at an unprecedented rate costing ranchers billions of dollars to control invasive plants each year. In its simplest form, the invasion process has four primary stages, including introduction, establishment, spread and colonization. Th...
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Richardson, A. J.; Escobar, D. E.; Gausman, H. W.; Everitt, J. H. (Principal Investigator)
1982-01-01
The accuracy was assessed for an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the LANDSAT satellite multispectral scanner (MSS) and a ground based spectroradiometer. The rangeland plant reflectances produced by the two sensors were correlated with no significant deviation of the slope from unity or of the intercept from zero. These results indicated that the atmospheric correction produced LANDSAT MSS estimates of rangeland plant reflectances that are as accurate as the ground based spectroradiometer.
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Introducing cattle grazing to a noxious weed-dominated rangeland shifts plant communities
Directory of Open Access Journals (Sweden)
Josh S. Davy
2015-10-01
Full Text Available Invasive weed species in California's rangelands can reduce herbaceous diversity, forage quality and wildlife habitat. Small-scale studies (5 acres or fewer have shown reductions of medusahead and yellow starthistle using prescribed grazing on rangelands, but little is published on the effects of pasture-scale (greater than 80 acres prescribed grazing on weed control and plant community responses. We report the results of a 6-year collaborative study of manager-applied prescribed grazing implemented on rangeland that had not been grazed for 4 years. Grazing reduced medusahead but did not alter yellow starthistle cover. Medusahead reductions were only seen in years that did not have significant late spring rainfall, suggesting that it is able to recover from heavy grazing if soil moisture is present. Later season grazing appears to have the potential to suppress medusahead in all years. In practice, however, such grazing is constrained by livestock drinking water availability and forage quality, which were limited even in years with late spring rainfall. Thus, we expect that grazing treatments under real-world constraints would reduce medusahead only in years with little late spring rainfall. After 10 years of grazing exclusion, the ungrazed plant communities began to shift, replacing medusahead with species that have little value, such as ripgut and red brome.
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Restoration efforts in the western US occur across a diverse array of plant communities and climatic conditions. Restoration is likely constrained by different factors in different locations, but few efforts have compared the outcomes of rangeland restoration experiments across broad spatial scales....
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Drolet, Barbara S.; Stuart, Melissa A.; Derner, Justin D.
2009-01-01
Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV. PMID:19286779
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Drolet, Barbara S; Stuart, Melissa A; Derner, Justin D
2009-05-01
Knowledge of the many mechanisms of vesicular stomatitis virus (VSV) transmission is critical for understanding of the epidemiology of sporadic disease outbreaks in the western United States. Migratory grasshoppers [Melanoplus sanguinipes (Fabricius)] have been implicated as reservoirs and mechanical vectors of VSV. The grasshopper-cattle-grasshopper transmission cycle is based on the assumptions that (i) virus shed from clinically infected animals would contaminate pasture plants and remain infectious on plant surfaces and (ii) grasshoppers would become infected by eating the virus-contaminated plants. Our objectives were to determine the stability of VSV on common plant species of U.S. Northern Plains rangelands and to assess the potential of these plant species as a source of virus for grasshoppers. Fourteen plant species were exposed to VSV and assayed for infectious virus over time (0 to 24 h). The frequency of viable virus recovery at 24 h postexposure was as high as 73%. The two most common plant species in Northern Plains rangelands (western wheatgrass [Pascopyrum smithii] and needle and thread [Hesperostipa comata]) were fed to groups of grasshoppers. At 3 weeks postfeeding, the grasshopper infection rate was 44 to 50%. Exposure of VSV to a commonly used grasshopper pesticide resulted in complete viral inactivation. This is the first report demonstrating the stability of VSV on rangeland plant surfaces, and it suggests that a significant window of opportunity exists for grasshoppers to ingest VSV from contaminated plants. The use of grasshopper pesticides on pastures would decrease the incidence of a virus-amplifying mechanical vector and might also decontaminate pastures, thereby decreasing the inter- and intraherd spread of VSV.
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Measuring ecological function on California's rangelands
Porzig, E.
2016-12-01
There is a need for a better understanding of ecosystem processes on rangelands and how management decisions influence these processes on scales that are both ecologically and socially relevant. Point Blue Conservation Science's Rangeland Monitoring Network is a coordinated effort to collect standardized data on birds, vegetation, and soils on rangelands throughout California. We work with partners, including private landowners, land trusts, state and federal agencies, and others, to measure bird and plant abundance and diversity and three soil dynamic properties (water infiltration, bulk density, and organic carbon). Here, we present data from our first two years of monitoring on over 50 ranches in 17 counties. By collecting data on the scope and scale of variation in ecological function across rangelands and the relationship with management practices, we aim to advance rangeland management, restoration, and conservation.
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Symstad, Amy J.; Jonas, Jayne L.
2011-01-01
Indicators of rangeland health generally do not include a measure of biodiversity. Increasing attention to maintaining biodiversity in rangelands suggests that this omission should be reconsidered, and plant species richness and diversity are two metrics that may be useful and appropriate. Ideally, their response to a variety of anthropogenic and natural drivers in the ecosystem of interest would be clearly understood, thereby providing a means to diagnose the cause of decline in an ecosystem. Conceptual ecological models based on ecological principles and hypotheses provide a framework for this understanding, but these models must be supported by empirical evidence if they are to be used for decision making. To that end, we synthesize results from published studies regarding the responses of plant species richness and diversity to drivers that are of management concern in Great Plains grasslands, one of North America's most imperiled ecosystems. In the published literature, moderate grazing generally has a positive effect on these metrics in tallgrass prairie and a neutral to negative effect in shortgrass prairie. The largest published effects on richness and diversity were caused by moderate grazing in tallgrass prairies and nitrogen fertilization in shortgrass prairies. Although weather is often cited as the reason for considerable annual fluctuations in richness and diversity, little information about the responses of these metrics to weather is available. Responses of the two metrics often diverged, reflecting differences in their sensitivity to different types of changes in the plant community. Although sufficient information has not yet been published for these metrics to meet all the criteria of a good indicator in Great Plains Grasslands, augmenting current methods of evaluating rangeland health with a measure of plant species richness would reduce these shortcomings and provide information critical to managing for biodiversity.
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El-Keblawy, Ali; El-Sheikh, Mohamed
2017-04-01
Grazing and drought can adversely affect the ecology and management of rangeland ecosystems. Several management actions have been applied to restore species diversity and community structure in degraded rangelands of the unpredictable arid environment. Protection from grazing is considered as a proper approach for restoration of degraded rangelands, but this depends on substrate type and sometime is hindered with water deficiency (drought). In this study, the effect of protection from grazing animals on species diversity and plant community structure was assessed after a dry and wet periods in both sandy and gravelly substrates in the Dubai Desert Conservation reserve (DDCR), United Arab Emirates. Two sites were selected during November 2012 on the two substrate types (fixed sandy flat and gravel plain) in the arid DDCR. An enclosure was established in each site. Plant community attributes (plant cover, density, frequency, species composition, and diversity indices) were assessed in a number of permanent plots laid inside and outside each enclosure during November 2012, April 2014 and April 2016. The results showed that protection improved clay content, but decreased the organic matters. Interestingly, the protection reduced the concentrations of most estimated nutrients, which could be attributed to the high turnover rate of nutrients associated grazing and low decomposition of accumulated dry plants of non-protected sites. Protection significantly increased all plant community attributes, but the only significant effect was for plant density. Plant density was almost twice greater inside than outside the enclosures. During the dry period, protection resulted in significantly greater deterioration in cover, density and all diversity indices in gravel, compared to sandy sites. Most of the grasses and shrubby plants had died in the gravel plains. However, plant community of the gravel plains was significantly restored after receiving considerable rainfalls. The
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Hoppe, Franziska; Zhusui Kyzy, Taalaigul; Usupbaev, Adilet; Schickoff, Udo
2017-04-01
At least 30% of Kyrgyz pasture areas are considered to be subject to vegetation and soil degradation. Since animal husbandry is the economic basis to sustain people's livelihoods, rangeland degradation presents a threat for the majority of the population. Recently, the usage of plant functional traits as a powerful tool for the characterization of vegetation dynamics in response to anthropogenic and natural disturbances has been put forward. Grazing is one of the most severe disturbances on vegetation, which concerns equally the loss of area and biomass. Because grazing is both depending on and affecting plant functional traits, important insights can be generated, based on this codependency. We hypothesized that the contrasting grazing intensity of summer and winter pastures is reflected by the chosen traits. We used traits such as plant height, flowering start, growth form as well as SLA (Specific Leaf Area) and LMA (Leaf Mass per Area). Based on former phytosociological classification of the main pasture types (summer and winter pastures), community structure and the traits of dominant plant species were analyzed. Our results showed that on winter pastures grazing decreased plant height and SLA and favored plants with an earlier flowering start as well as rosette plants and ascending plants. We conclude that the study of trait composition in relation to anthropogenic disturbances can provide important insights into the mechanism of plant response to grazing in high-altitude rangelands.
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New Tools to Estimate Runoff, Soil Erosion, and Sustainability of Rangeland Plant Communities
Rangelands are the largest land cover type in the world. Degradation from mismanagement, desertification, and drought impact more than 50% of rangelands across the globe. The USDA Agricultural Research Service has been evaluating sustainability of rangeland for over 40-years by conducted rangeland r...
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Directory of Open Access Journals (Sweden)
Mohammed Mussa Abdulahi
2016-12-01
Full Text Available In the lowlands of arid and semiarid rangelands woody plants plays an important role in soil fertility maintenance, providing food, medicine, cosmetics, fodder, fuel wood and pesticides. A better understanding of the interaction of woody plants on their immediate environment is needed to guide optimum management of native vegetation in the production landscapes. However, the impact of woody plant species on soil properties remains poorly understood. This study evaluates the impact of two dominant woody plant species (A. senegal and B. aegyptica on soil physico-chemical properties along grazing gradients in rangelands of eastern Ethiopia. Six trees of each species were selected from light, moderate and heavy grazing sites. Soil sample data at two depths (0-15 and 16-30 cm were collected from under and open areas of A. senegal and B. aegyptica from each grazing sites, and analysed for nutrient contents. The nutrient status of soil under both woody species was significantly higher especially with regard to soil organic matter (4.37%, total nitrogen (0.313%, and available phosphorus (11.62 than the open grassland with soil organic matter (3.82%, total nitrogen (0.246%, and available phosphorus (10.94 mg/Kg soil for A. Senegal. The soil organic matter (3.93%, total nitrogen (0.285%, available phosphorus (11.66 mg/Kg soil were significantly higher than open grassland with soil organic matter (3.52%, total nitrogen (0.218%, available phosphorus (10.73 mg/Kg soil for B. aegyptica. This was more pronounced in the top 15 cm of soil under A. senegal woody plant species and on the light and moderate grazing site. Therefore, this tree has a significant effect on soil fertility improvement in resource poor rangelands and as a result, it is important to retain scattered A. senegal and B. aegyptica plants in the lowlands of eastern Ethiopia.
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Climate impacts on agriculture: Implications for forage and rangeland production
Energy Technology Data Exchange (ETDEWEB)
Izaurralde, Roberto C.; Thomson, Allison M.; Morgan, Jack; Fay, Philip; Polley, Wayne; Hatfield, Jerry L.
2011-04-19
Projections of temperature and precipitation patterns across the United States during the next 50 years anticipate a 1.5 to 2°C warming and a slight increase in precipitation as a result of global climate change. There have been relatively few studies of climate change impacts on pasture and rangeland (grazingland) species compared to those on crop species, despite the economic and ecological importance of the former. Here we review the literature on pastureland and rangeland species to rising CO2 and climate change (temperature, and precipitation) and discuss plant and management factors likely to influence pastureland and rangeland responses to change (e.g., community composition, plant competition, perennial growth habit, seasonal productivity, and management methods). Overall, the response of pasture species to increased [CO2] is consistent with the general response of C3 and C4 type vegetation, although significant exceptions exist. Both pastureland and rangeland species should exhibit an acceleration of metabolism and development due to earlier onset of spring green-up and longer growing seasons. However, in the studies reviewed here, C3 pasture species increased their photosynthetic rates by up to 40% while C4 species exhibited no increase in photosynthesis. In general, it is expected that increases in [CO2] and precipitation would enhance rangeland net primary production (NPP) while increased air temperatures would either increase or decrease NPP. Much of this uncertainty in response is due to uncertain future projections of precipitation, both globally and regionally. For example, if annual precipitation changes little or declines, rangeland plant response to warming temperatures and rising [CO2] may be neutral or may decline due to increased water stress. This review reveals the need for comprehensive studies of climate change impacts on the pasture ecosystem including grazing regimes, mutualistic relationships (e.g., plant roots-nematodes; N
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CSIR Research Space (South Africa)
Munyati, C
2011-05-01
Full Text Available rangeland, whereas the communal rangelands were getting more opened up by livestock trampling. Rangeland management practices of fire utilisation, stocking levels and stock concentration account for the differing trends. Lightly grazed and heavily grazed...
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Bush encroachment dynamics and rangeland management implications in the Horn of Africa
Rangelands in the Horn of Africa have been undergoing a rapid shift from herbaceous to woody plant dominance in the past decades, threatening subsistence livestock herding and pastoral food security. Despite of significant rangeland management implications, quantification of the spatial extent of en...
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Directory of Open Access Journals (Sweden)
Mohammed Mussa Abdulahi
2016-12-01
Full Text Available Rangeland degradation remains a serious impediment to improve pastoral livelihoods in the lowlands of Ethiopia. This review paper presents an overview of the extent of rangeland degradation, explores its drivers, discusses the potential impacts of rangeland degradation and also suggests alternative rangeland restoration techniques. It is intended to serve as an exploratory tool for ensuing more detailed quantitative analyses to support policy and investment programs to address rangeland degradation in Ethiopia. The extent of rangeland degradation increases with time, and the productivity of rangelands are losing if not given due attention. The major drivers leading to rangeland degradation includes climate change, overgrazing, bush encroachment, population pressure, drought, and government policy, encroachment of rain fed agriculture and decline of traditional resource management institution. Degradation of rangeland has resulted in substantial declines in rangeland condition, water potential, soil status, and animal performance, livestock holding at the household level and community become destitute. Another consequence of rangeland degradation is linked to food insecurity, poverty to the extent of food aid, expansion of aridity and the need for alternative livelihood and income diversification. Moreover, it has increasingly become a threat to the pastoral production systems, and has contributed towards increases in poverty and tribal conflicts over grazing land and water resources. In spite of these impacts, the adoption of alternative restoration techniques in the country is highly insufficient. To address rangeland degradation problems, there is a strong need to substantially increase the investments and strengthen the policy support for sustainable land management.
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Applying a dryland degradation framework for rangelands: the case of Mongolia.
Jamsranjav, C; Reid, R S; Fernández-Giménez, M E; Tsevlee, A; Yadamsuren, B; Heiner, M
2018-04-01
Livestock-caused rangeland degradation remains a major policy concern globally and the subject of widespread scientific study. This concern persists in part because it is difficult to isolate the effects of livestock from climate and other factors that influence ecosystem conditions. Further, degradation studies seldom use multiple plant and soil indicators linked to a clear definition of and ecologically grounded framework for degradation assessment that distinguishes different levels of degradation. Here, we integrate two globally applicable rangeland degradation frameworks and apply them to a broad-scale empirical data set for the country of Mongolia. We compare our assessment results with two other recent national rangeland degradation assessments in Mongolia to gauge consistency of findings across assessments and evaluate the utility of our framework. We measured livestock-use impacts across Mongolia's major ecological zones: mountain and forest steppe, eastern steppe, steppe, and desert steppe. At 143 sites in 36 counties, we measured livestock-use and degradation indicators at increasing distances from livestock corrals in winter-grazed pastures. At each site, we measured multiple indicators linked to our degradation framework, including plant cover, standing biomass, palatability, species richness, forage quality, vegetation gaps, and soil surface characteristics. Livestock use had no effect on soils, plant species richness, or standing crop biomass in any ecological zone, but subtly affected plant cover and palatable plant abundance. Livestock effects were strongest in the steppe zone, moderate in the desert steppe, and limited in the mountain/forest and eastern steppes. Our results aligned closely with those of two other recent country-wide assessments, suggesting that our framework may have widespread application. All three assessments found that very severe and irreversible degradation is rare in Mongolia (1-18% of land area), with most rangelands
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Impact of Rangeland Degradation on Soil Physical, Chemical
African Journals Online (AJOL)
major threats to enhance a sustainable pastoral-livestock production in Ethiopia. ... overall negative impact on the soil physical and chemical characteristics, demanding ... chemical properties (Gemedo et al., 2006) as well as the rangeland .... parameters such as life forms (annuals and perennials), plant forms (woody plant,.
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Weather-centric rangeland revegetation planning
Hardegree, Stuart P.; Abatzoglou, John T.; Brunson, Mark W.; Germino, Matthew; Hegewisch, Katherine C.; Moffet, Corey A.; Pilliod, David S.; Roundy, Bruce A.; Boehm, Alex R.; Meredith, Gwendwr R.
2018-01-01
Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a weather-centric approach that uses the full spectrum of available site-specific weather information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental variability subsequent to planting. A more detailed evaluation of weather impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new weather technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.
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The utility of Ecological Site Descriptions (ESDs) and State-and-Transition Models (STMs) concepts in guiding rangeland management hinges on their ability to accurately describe and predict community dynamics and the associated consequences. For many rangeland ecosystems, plant community dynamics ar...
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RANGELAND SEQUESTRATION POTENTIAL ASSESSMENT
Energy Technology Data Exchange (ETDEWEB)
Lee Spangler; George F. Vance; Gerald E. Schuman; Justin D. Derner
2012-03-31
Rangelands occupy approximately half of the world's land area and store greater than 10% of the terrestrial biomass carbon and up to 30% of the global soil organic carbon. Although soil carbon sequestration rates are generally low on rangelands in comparison to croplands, increases in terrestrial carbon in rangelands resulting from management can account for significant carbon sequestration given the magnitude of this land resource. Despite the significance rangelands can play in carbon sequestration, our understanding remains limited. Researchers conducted a literature review to identify sustainably management practices that conserve existing rangeland carbon pools, as well as increase or restore carbon sequestration potentials for this type of ecosystem. The research team also reviewed the impact of grazing management on rangeland carbon dynamics, which are not well understood due to heterogeneity in grassland types. The literature review on the impact of grazing showed a wide variation of results, ranging from positive to negative to no response. On further review, the intensity of grazing appears to be a major factor in controlling rangeland soil organic carbon dynamics. In 2003, researchers conducted field sampling to assess the effect of several drought years during the period 1993-2002. Results suggested that drought can significantly impact rangeland soil organic carbon (SOC) levels, and therefore, carbon sequestration. Resampling was conducted in 2006; results again suggested that climatic conditions may have overridden management effects on SOC due to the ecological lag of the severe drought of 2002. Analysis of grazing practices during this research effort suggested that there are beneficial effects of light grazing compared to heavy grazing and non-grazing with respect to increased SOC and nitrogen contents. In general, carbon storage in rangelands also increases with increased precipitation, although researchers identified threshold levels of
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Assessing Rangeland Attributes On Semi-Arid Zone Of North Darfur State Sudan
Directory of Open Access Journals (Sweden)
Mohamed Almontasir A. M. Mohamed
2015-08-01
Full Text Available Abstract The study was conducted over a two years period of 2012 and 2013 at three sites of Alfashir locality Ummarahik 25km north of Alfashir Fashar in eastern part of Alfashir about 5km and Berka 30km west of Alfashir Western Sudan in semi-arid zone. The aim of this study was to assess rangeland attributes. Measurements of plant density vegetation cover range production and carrying capacity were assessed. Results showed that total forage production was low and inadequate to satisfy requirements of livestock for inhabiting the area average range production all over the area was found to be 50.68 kgha and 59.21 kgha for the seasons 2012 and 2013 respectively. The average ground cover was about 34.71 and 42.41 for two seasons. The average plant density for the first season was 27.1 plantm2 while the average plant density for the second season was 29.4 plantm2. The study concluded that unwise utilization and exploitation of the rangelands particularly by man causes range deterioration and serious reduction in range production in both quantity and quality so the study suggested that improvement and rehabilitation such lands rangelands should be done. Further research work is needed to assess rangeland attributes across different ecological zones in North Darfur State.
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EVALUATION AND MAPPING OF RANGELANDS DEGRADATION USING REMOTELY SENSED DATA
Directory of Open Access Journals (Sweden)
Majid Ajorlo
2005-05-01
Full Text Available The empirical and scientifically documents prove that misuse of natural resource causes degradation in it. So natural resources conservation is important in approaching sustainable development aims. In current study, Landsat Thematic Mapper images and grazing gradient method have been used to map the extent and degree of rangeland degradation. In during ground-based data measuring, factors such as vegetation cover, litter, plant diversity, bare soil, and stone & gravels were estimated as biophysical indicators of degradation. The next stage, after geometric correction and doing some necessary pre-processing practices on the study area’s images; the best and suitable vegetation index has been selected to map rangeland degradation among the Normalized Difference Vegetation Index (NDVI, Soil Adjusted Vegetation Index (SAVI, and Perpendicular Vegetation Index (PVI. Then using suitable vegetation index and distance parameter was produced the rangelands degradation map. The results of ground-based data analysis reveal that there is a significant relation between increasing distance from critical points and plant diversity and also percentage of litter. Also there is significant relation between vegetation cover percent and distance from village, i.e. the vegetation cover percent increases by increasing distance from villages, while it wasn’t the same around the stock watering points. The result of analysis about bare soil and distance from critical point was the same to vegetation cover changes manner. Also there wasn’t significant relation between stones & gravels index and distance from critical points. The results of image processing show that, NDVI appears to be sensitive to vegetation changes along the grazing gradient and it can be suitable vegetation index to map rangeland degradation. The degradation map shows that there is high degradation around the critical points. These areas need urgent attention for soil conservation. Generally, it
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Sovada, M.A.; Roy, C.C.; Telesco, D.J.
2001-01-01
Food habits of swift foxes (Vulpes velox) occupying two distinct landscapes (dominated by cropland versus rangeland) in western Kansas were determined by analysis of scats collected in 1993 and 1996. Frequencies of occurrence of prey items in scats were compared between cropland and rangeland areas by season. Overall, the most frequently occurring foods of swift foxes were mammals (92% of all scats) and arthropods (87%), followed by birds (24%), carrion (23%), plants (15%) and reptiles (4%). No differences were detected between landscapes for occurrence of mammals, arthropods or carrion in any season (P ≥ 0.100). Plants, specifically commercial sunflower seeds, were consumed more frequently in cropland than in rangeland in spring (P = 0.004) and fall (P = 0.001). Birds were more common in the swift fox diet in cropland than in rangeland during the fall (P = 0.008), whereas reptiles occurred more frequently in the diet in rangeland than in cropland during spring (P = 0.042). Variation in the diet of the swift fox between areas was most likely due to its opportunistic foraging behavior, resulting in a diet that closely links prey use with availability.
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Exploring the invasion of rangelands by Acacia mearnsii (black ...
African Journals Online (AJOL)
Reducing A. mearnsii canopy could promote grass production while encouraging carbon sequestration. Given the high AGB and clearing costs, it may be prudent to adopt the 'novel ecosystems' approach in managing infested landscapes. Keywords: grassland, invasive plants, landscape ecology, rangeland condition ...
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Rangelands represent the dominant land use systems in many countries of the world and provide sociological and cultural benefits to millions of people in both rural and urban areas. The undesirable impacts of rangeland weeds have been recognized for well over 100 years and infest between 41 and 51 ...
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Introduced and invasive species in novel rangeland ecosystems: friends or foes?
Belnap, Jayne; Ludwig, John A.; Wilcox, Bradford P.; Betancourt, Julio L.; Dean, W. Richard J.; Hoffmann, Benjamin D.; Milton, Sue J.
2012-01-01
Globally, new combinations of introduced and native plant and animal species have changed rangelands into novel ecosystems. Whereas many rangeland stakeholders (people who use or have an interest in rangelands) view intentional species introductions to improve forage and control erosion as beneficial, others focus on unintended costs, such as increased fire risk, loss of rangeland biodiversity, and threats to conservation efforts, specifically in nature reserves and parks. These conflicting views challenge all rangeland stakeholders, especially those making decisions on how best to manage novel ecosystems. To formulate a conceptual framework for decision making, we examined a wide range of novel ecosystems, created by intentional and unintentional introductions of nonnative species and land-use–facilitated spread of native ones. This framework simply divides decision making into two types: 1) straightforward–certain, and 2) complex–uncertain. We argue that management decisions to retain novel ecosystems are certain when goods and services provided by the system far outweigh the costs of restoration, for example in the case of intensively managed Cenchrus pastures. Decisions to return novel ecosystems to natural systems are also certain when the value of the system is low and restoration is easy and inexpensive as in the case of biocontrol of Opuntia infestations. In contrast, decisions whether to retain or restore novel ecosystems become complex and uncertain in cases where benefits are low and costs of control are high as, for example, in the case of stopping the expansion of Prosopis and Juniperus into semiarid rangelands. Decisions to retain or restore novel ecosystems are also complex and uncertain when, for example, nonnative Eucalyptus trees expand along natural streams, negatively affecting biodiversity, but also providing timber and honey. When decision making is complex and uncertain, we suggest that rangeland managers utilize cost–benefit analyses
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Earth observation for rangeland monitoring
CSIR Research Space (South Africa)
Ramoelo, Abel
2012-10-01
Full Text Available .kashan.co.za] INTRODUCTION Grass nitrogen (N), as an indicator of rangeland quality, plays a crucial role in understanding the distribution, densities and feeding patterns of both wild herbivores and livestock. Zebras and livestock in the grazing and agricultural lands... ? How can grass nitrogen be mapped for assessing and monitoring of rangeland quality at wider or regional scales? ? Conventional point-based techniques for assessing rangeland quality proved to be expensive, laborious and time consuming...
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Carbon fluxes on North American rangelands
Tony Svejcar; Raymond Angell; James A. Bradford; William Dugas; William Emmerich; Albert B. Frank; Tagir Gilmanov; Marshall Haferkamp; Douglas A. Johnson; Herman Mayeux; Pat Mielnick; Jack Morgan; Nicanor Z. Saliendra; Gerald E. Schuman; Phillip L. Sims; Kereith Snyder
2008-01-01
Rangelands account for almost half of the earth's land surface and may play an important role in the global carbon (C) cycle. We studied net ecosystem exchange (NEE) of C on eight North American rangeland sites over a 6-yr period. Management practices and disturbance regimes can influence NEE; for consistency, we compared ungrazed and undisturbed rangelands...
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Ecosystem water availability in juniper versus sagebrush snow-dominated rangelands
Western Juniper (J. occidentalis Hook.) now dominates over 3.6 million ha of rangeland in the Intermountain Western US. Critical ecological relationships among snow distribution, water budgets, plant community transitions, and habitat requirements for wildlife, such as sage grouse, remain poorly und...
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Criterion III: Maintenance of rangeland productive capacity [Chapter 4
G. R. Evans; R. A. Washmgton-Allen; R. D. Child; J. E. Mitchell; B. R. Bobowskl; R. V. Loper; B. H. Allen-Diaz; D. W. Thompson; G. R. Welling; T. B. Reuwsaat
2010-01-01
Maintenance of rangeland productive capacity is one of five criteria established by the Sustainable Rangelands Roundtable (SRR) to monitor and assess rangeland sustainable management. Within this criterion, six indicators were developed through the Delphi Process and the expert opinions of academicians, rangeland scientists, rangeland management agency personnel, non-...
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Directory of Open Access Journals (Sweden)
Nathan F. Sayre
2012-12-01
Full Text Available Discussions of diversified farming systems (DFS rarely mention rangelands: the grasslands, shrublands, and savannas that make up roughly one-third of Earth's ice-free terrestrial area, including some 312 million ha of the United States. Although ranching has been criticized by environmentalists for decades, it is probably the most ecologically sustainable segment of the U.S. meat industry, and it exemplifies many of the defining characteristics of DFS: it relies on the functional diversity of natural ecological processes of plant and animal (reproduction at multiple scales, based on ecosystem services generated and regenerated on site rather than imported, often nonrenewable, inputs. Rangelands also provide other ecosystem services, including watershed, wildlife habitat, recreation, and tourism. Even where non-native or invasive plants have encroached on or replaced native species, rangelands retain unusually high levels of plant diversity compared with croplands or plantation forests. Innovations in management, marketing, incentives, and easement programs that augment ranch income, creative land tenure arrangements, and collaborations among ranchers all support diversification. Some obstacles include rapid landownership turnover, lack of accessible U.S. Department of Agriculture certified processing facilities, tenure uncertainty, fragmentation of rangelands, and low and variable income, especially relative to land costs. Taking advantage of rancher knowledge and stewardship, and aligning incentives with production of diverse goods and services, will support the sustainability of ranching and its associated public benefits. The creation of positive feedbacks between economic and ecological diversity should be the ultimate goal.
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Weather-centric rangeland revegetation planning
Semiarid rangelands in the western United States have been or are being invaded by introduced annual weeds that negatively impact ecosystem services and pose a major conservation threat. Rehabilitation and restoration of these rangelands are challenging due to inter-annual climate and sub-seasonal ...
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Rangelands: Where Anthromes Meet Their Limits
Directory of Open Access Journals (Sweden)
Nathan F. Sayre
2017-05-01
Full Text Available Defining rangelands as anthromes enabled Ellis and Ramankutty (2008 to conclude that more than three-quarters of Earth’s land is anthropogenic; without rangelands, this figure would have been less than half. They classified all lands grazed by domestic livestock as rangelands, provided that human population densities were low; similar areas without livestock were excluded and classified instead as ‘wildlands’. This paper examines the empirical basis and conceptual assumptions of defining and categorizing rangelands in this fashion. Empirically, we conclude that a large proportion of rangelands, although used to varying degrees by domesticated livestock, are not altered significantly by this use, especially in arid, highly variable environments and in settings with long evolutionary histories of herbivory by wild animals. Even where changes have occurred, the dynamics and components of many rangelands remain structurally and functionally equivalent to those that preceded domestic livestock grazing or would be found in its absence. In much of Africa and Asia, grazing is so longstanding as to be inextricable from ‘natural’ or reference conditions for those sites. Thus, the extent of anthropogenic biomes is significantly overstated. Conceptually, rangelands reveal the dependence of the anthromes thesis on outdated assumptions of ecological climax and equilibrium. Coming to terms with rangelands—how they can be classified, understood, and managed sustainably—thus offers important lessons for understanding anthromes and the Anthropocene as a whole. At the root of these lessons, we argue, is not the question of human impacts on ecosystems but property relations among humans.
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The Rangeland Hydrology and Erosion Model: A dynamic approach for predicting soil loss on rangelands
In this study we present the improved Rangeland Hydrology and Erosion Model (RHEM V2.3), a process-based erosion prediction tool specific for rangeland application. The article provides the mathematical formulation of the model and parameter estimation equations. Model performance is assessed agains...
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Conserving biodiversity on native rangelands: Symposium proceedings
Daniel W. Uresk; Greg L. Schenbeck; James T. O' Rourke
1997-01-01
These proceedings are the result of a symposium, "Conserving biodiversity on native rangelands" held on August 17, 1995 in Fort Robinson State Park, NE. The purpose of this symposium was to provide a forum to discuss how elements of rangeland biodiversity are being conserved today. We asked, "How resilient and sustainable are rangeland systems to the...
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Directory of Open Access Journals (Sweden)
Mohamed AAMA Mohamed
2014-09-01
Full Text Available This study was conducted at Um Kaddada, North Darfur State, Sudan, at two sites (closed and open for two consecutive seasons 2008 and 2009 during flowering and seed setting stages to evaluate range attributes at the locality. A split plot design was used to study vegetation attributes. Factors studied were management systems (closed and open and growth stages (flowering and seed setting. Vegetation cover, plant density, carrying capacity, and biomass production were assessed. Chemical analyses were done for selected plants to determine their nutritive values. The results showed high significant differences in vegetation attributes (density, cover and biomass production between closed and open areas. Closed areas had higher carrying capacity compared to open rangelands. Crude protein (CP and ash contents of range vegetation were found to decrease while Crude fiber (CF and Dry matter yield (DM had increased with growth. The study concluded that closed rangelands are better than open rangelands because it fenced and protected. Erosion index and vegetation degradation rate were very high. Future research work is needed to assess rangelands characteristics and habitat condition across different ecological zones in North Darfur State, Sudan.DOI: http://dx.doi.org/10.3126/ije.v3i3.11093 International Journal of Environment Vol.3(3 2014: 332-343
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75 FR 8036 - Monitor-Hot Creek Rangeland Project
2010-02-23
... DEPARTMENT OF AGRICULTURE Forest Service Monitor-Hot Creek Rangeland Project AGENCY: Forest... Rangeland Project area. The analysis will determine if a change in management direction for livestock grazing is needed to move existing resource conditions within the Monitor-Hot Creek Rangeland Project area...
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A systematic review of US rangeland social science
Rangeland science aims to create knowledge to sustain rangeland social-ecological systems over the long term. Range science has made substantial progress on understanding ecological dynamics of rangeland systems and the management practices that sustain them, and these findings have been systematica...
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Valuation of rangeland ecosystem services
Gascoigne, W.R.
2011-01-01
Economic valuation lends itself well to the anthropocentric orientation of ecosystem services. An economic perspective on ecosystems portrays them as natural assets providing a flow of goods and services valuable to individuals and society collectively. A few examples include the purification of drinking water, reduced risk from flooding and other extreme events, pollination of agricultural crops, climate regulation, and recreation opportunities from plant and animal habitat maintenance, among many others. Once these goods and services are identified and quantified, they can be monetized to complete the valuation process. The monetization of ecosystem goods and services (in the form of dollars) provides a common metric that allows for cross-comparison of attributes and evaluation of differing ecological scenarios. Complicating the monetization process is the fact that most of these goods and services are public and non-market in nature; meaning they are non-rival and non-exclusive and are typically not sold in a traditional market setting where monetary values are revealed. Instead, one must employ non-market valuation techniques, with primary valuation methods typically being very time and resource consuming, intimidating to non-economists, and often impractical. For these reasons, benefit transfer methods have gained popularity. This methodology harnesses the primary collection results of existing studies to make inferences about the economic values of non-market goods and services at an alternative policy site (in place and/or in time). For instance, if a primary valuation study on oak reestablishment on rangelands in southern California yielded a value of $30 per-acre associated with water regulation, this result can be transferred, with some adjustments, to say something about the value of an acre of oaks on rangelands in northern portions of the state. The economic valuation of rangeland ecosystem services has many roles. Economic values may be used as input
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Rangeland monitoring and assessment: a review
CSIR Research Space (South Africa)
Ramoelo, Abel
2018-04-01
Full Text Available Rangelands provide vast landscapes for grazing and foraging for livestock and wildlife. Services of rangelands are diverse and generally provide food for millions of the world’s population, especially the rural and sometimes poor communities...
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A RANGELAND GRASSHOPPER INSURANCE PROGRAM
Skold, Melvin D.; Davis, Robert M.
1995-01-01
The incidence of benefits and costs from controlling rangeland grasshoppers on public grazing lands poses problems of economic efficiency and distributional equity. Public grasshopper control programs operate like public disaster assistance. However, grasshopper infestations are an insurable risk. This article proposes a rangeland grasshopper insurance program which reduces the economic inefficiencies and distributional inequities of the existing program.
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Developing an operational rangeland water requirement satisfaction index
Senay, Gabriel B.; Verdin, James P.; Rowland, James
2011-01-01
Developing an operational water requirement satisfaction index (WRSI) for rangeland monitoring is an important goal of the famine early warning systems network. An operational WRSI has been developed for crop monitoring, but until recently a comparable WRSI for rangeland was not successful because of the extremely poor performance of the index when based on published crop coefficients (K c) for rangelands. To improve the rangeland WRSI, we developed a simple calibration technique that adjusts the K c values for rangeland monitoring using long-term rainfall distribution and reference evapotranspiration data. The premise for adjusting the K c values is based on the assumption that a viable rangeland should exhibit above-average WRSI (values >80%) during a normal year. The normal year was represented by a median dekadal rainfall distribution (satellite rainfall estimate from 1996 to 2006). Similarly, a long-term average for potential evapotranspiration was used as input to the famine early warning systems network WRSI model in combination with soil-water-holding capacity data. A dekadal rangeland WRSI has been operational for east and west Africa since 2005. User feedback has been encouraging, especially with regard to the end-of-season WRSI anomaly products that compare the index's performance to ‘normal’ years. Currently, rangeland WRSI products are generated on a dekadal basis and posted for free distribution on the US Geological Survey early warning website at http://earlywarning.usgs.gov/adds/
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Rangelands are the most dominant land cover type in the United States (770 million acres) with approximately 53% of the nation’s rangelands owned and managed by the private sector, while approximately 43% are managed by the federal government. Information on the type, extent, and spatial location of...
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Meeting wild bees' needs on rangelands
Some arid rangeland regions, notably those with warm dry climates of the temperate zones, host great diversities of native bees, primarily non-social species among which are many floral specialists. Rangeland bee faunas are threatened indirectly by invasive exotic weeds wherever these displace nat...
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Principles of optimizing animal production from rangeland
International Nuclear Information System (INIS)
Stubbendieck, J.; Waller, S.S.
1983-01-01
Increasing world population is one of the dominant factors escalating demands for the world's natural resources. Range and forage resources, which are used primarily for food and fibre, could be more efficiently used if management techniques were improved. The principles of managing forage resources are directly associated with both the growth and development of plants and the actions and needs of the grazing animal. An understanding of the effects of environmental factors and herbage removal (frequency, intensity and season of defoliation) on growth and regrowth of plants is the first step towards optimizing animal productivity from rangelands. Most potential changes will fit into three categories: (1) increase the quantity of forage, (2) improve the quality of forage, and (3) improve use of forage. The principles of grazing management can be separated into four intricately related categories: (1) proper degree of grazing, (2) proper season of grazing, (3) proper kind of livestock, and (4) proper distribution of grazing. Grazing management is affected by the manner in which both improvements and manipulation of vegetation affect forage yield and quality. The adaptation and application of existing knowledge to individual locations will be one step towards optimizing animal production from rangeland. Some of the problems may be solved through better dissemination of present knowledge through existing educational programmes, while others will require expanded programmes of information dissemination. A third group of problems may also be solved with present technology, but the solutions are not currently economical. Some of the problems will be solved only through expanded research. These research efforts need to be directed towards grazing or browsing animals, plant resources and the interaction between plants and animals. Application of nuclear techniques will be an integral part of this research. (author)
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Current situation of rangelands in Mexico
Alicia Melgoza-Castillo
2006-01-01
Rangelands are natural areas with certain characteristics that make them unsuitable for agriculture. They include several types of vegetation such as deserts, grasslands, shrubs, forests, and riparian areas. Cattle ranching, along with the products and services it engenders, is a prime activity that rangelands have traditionally supported.
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Opportunities and obstacles for rangeland conservation in San Diego County, California, USA
Directory of Open Access Journals (Sweden)
Kathleen A. Farley
2017-03-01
Full Text Available Working landscapes such as rangelands are increasingly recognized as having high conservation value, providing a variety of ecosystem services, including food, fiber, habitat, recreation, open space, carbon storage, and water, in addition to a broad range of social benefits. However, conversion of rangelands to other land uses has been prevalent throughout the western United States, leading to greater attention in the conservation community to the importance of collaborating with private landowners. The level of interest in collaborative conservation among private landowners and the types of conservation programs they choose to participate in depend on the social, economic, and environmental context. We used GIS analysis and interviews with ranchers to evaluate rangeland conversion and participation in conservation programs among ranchers in San Diego County, California, USA, which is part of a biodiversity hotspot with high plant species richness and a large number of endemic and rare species. We found that > 25% of rangelands were converted to other uses, primarily urbanization, over the past 25 years while the area of public rangeland increased by 9%. Interviews revealed that ranchers in San Diego County have had limited involvement with most conservation programs, and a critical factor for nonparticipation was providing programs access to private land, along with other issues related to trust and social values. Among ranchers who had participated in conservation programs, the payment level and the agency or organization administering the program were key factors. Our results provide insight into factors influencing whether and when ranchers are likely to participate in conservation initiatives and illustrate that private and public land conservation are strongly linked and would be more effective if the two strategies were better integrated.
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Assessing the impacts of livestock production on biodiversity in rangeland ecosystems
Alkemade, Rob; Reid, Robin S.; van den Berg, Maurits; de Leeuw, Jan; Jeuken, Michel
2013-01-01
Biodiversity in rangelands is decreasing, due to intense utilization for livestock production and conversion of rangeland into cropland; yet the outlook of rangeland biodiversity has not been considered in view of future global demand for food. Here we assess the impact of future livestock production on the global rangelands area and their biodiversity. First we formalized existing knowledge about livestock grazing impacts on biodiversity, expressed in mean species abundance (MSA) of the original rangeland native species assemblages, through metaanalysis of peer-reviewed literature. MSA values, ranging from 1 in natural rangelands to 0.3 in man-made grasslands, were entered in the IMAGE-GLOBIO model. This model was used to assess the impact of change in food demand and livestock production on future rangeland biodiversity. The model revealed remarkable regional variation in impact on rangeland area and MSA between two agricultural production scenarios. The area of used rangelands slightly increases globally between 2000 and 2050 in the baseline scenario and reduces under a scenario of enhanced uptake of resource-efficient production technologies increasing production [high levels of agricultural knowledge, science, and technology (high-AKST)], particularly in Africa. Both scenarios suggest a global decrease in MSA for rangelands until 2050. The contribution of livestock grazing to MSA loss is, however, expected to diminish after 2030, in particular in Africa under the high-AKST scenario. Policies fostering agricultural intensification can reduce the overall pressure on rangeland biodiversity, but additional measures, addressing factors such as climate change and infrastructural development, are necessary to totally halt biodiversity loss. PMID:22308313
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Accatino, F; Sabatier, R; De Michele, C; Ward, D; Wiegand, K; Meyer, K M
2014-08-01
Rangelands provide the main forage resource for livestock in many parts of the world, but maintaining long-term productivity and providing sufficient income for the rancher remains a challenge. One key issue is to maintain the rangeland in conditions where the rancher has the greatest possibility to adapt his/her management choices to a highly fluctuating and uncertain environment. In this study, we address management robustness and adaptability, which increase the resilience of a rangeland. After reviewing how the concept of resilience evolved in parallel to modelling views on rangelands, we present a dynamic model of rangelands to which we applied the mathematical framework of viability theory to quantify the management adaptability of the system in a stochastic environment. This quantification is based on an index that combines the robustness of the system to rainfall variability and the ability of the rancher to adjust his/her management through time. We evaluated the adaptability for four possible scenarios combining two rainfall regimes (high or low) with two herding strategies (grazers only or mixed herd). Results show that pure grazing is viable only for high-rainfall regimes, and that the use of mixed-feeder herds increases the adaptability of the management. The management is the most adaptive with mixed herds and in rangelands composed of an intermediate density of trees and grasses. In such situations, grass provides high quantities of biomass and woody plants ensure robustness to droughts. Beyond the implications for management, our results illustrate the relevance of viability theory for addressing the issue of robustness and adaptability in non-equilibrium environments.
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Maintaining ecosystem services through continued livestock production on California rangelands
Barry, S.; Becchetti, T.
2015-12-01
Nearly 40% of California is rangeland comprising the largest land type in California and providing forage for livestock, primarily beef cattle. In addition to forage, rangelands provide a host of ecosystem systems services, including habitat for common and endangered species, fire fuels management, pollination services, clean water, viewsheds, and carbon sequestration. Published research has documented that most of these ecosystem services are positively impacted by managed livestock grazing and rancher stewardship. Ranchers typically do not receive any monetary reimbursement for their stewardship in providing these ecosystem services to the public. Markets have been difficult to establish with limited ability to adequately monitor and measure services provided. At the same time, rangelands have been experiencing rapid conversion to urbanization and more profitable and intensive forms of agriculture such as almond and walnut orchards. To prevent further conversion of rangelands and the loss of the services they provide, there needs to be a mechanism to identify and compensate landowners for the value of all products and services being received from rangelands. This paper considers two methods (opportunity cost and avoided cost) to determine the value of Payment for Ecosystem Services (PES) for rangelands. PES can raise the value of rangelands, making them more competitive financially. Real estate values and University of California Cooperative Extension Cost Studies, were used to demonstrate the difference in value (lost opportunity cost) between the primary products of rangelands (livestock production) and the products of the converted rangelands (almond and walnut orchards). Avoided costs for vegetation management and habitat creation and maintenance were used to establish the value of managed grazing. If conversion is to be slowed or stopped and managed grazing promoted to protect the ecosystem services rangelands provide, this value could be compensated through
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Common garden experiments are a means to remove environmental effects. Using 8 species of perennial rangeland grasses, we established a common garden (3 reps x28 plants = 84 plants/species). We found that ‘Hycrest’ crested wheatgrass (Agropyron cristatum) and bluebunch wheatgrass (Pseudoroegneria sp...
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Remote sensing applications for monitoring rangeland vegetation ...
African Journals Online (AJOL)
Remote sensing techniques hold considerable promise for the inventory and monitoring of natural resources on rangelands. A significant lack of information concerning basic spectral characteristics of range vegetation and soils has resulted in a lack of rangeland applications. The parameters of interest for range condition ...
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Conserving rangeland resources. | Mentis | African Journal of Range ...
African Journals Online (AJOL)
... goal-attainment, (5) try to correct departures, and (6) align individual and societal interests by manipulating market-forces. Keywords: altruism; conservation; Conservation implementation; Conservation properties; human activity; Human values; philosophy; Range resources; rangeland; Rangelands; Science philosophy
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Sustainable rangeland management, economic growth, and a cautious role for the SRM
Interest in the art and science of rangeland management increased dramatically during the 20th century and it was out of this interest that the profession of rangeland management was born. As public interest in rangeland management grew, so did the number, breadth, and depth of rangeland management ...
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Pastoral Decision-Making: An Empirical Investigation of Rangeland Use
International Nuclear Information System (INIS)
MacPeak, J.
1999-01-01
Recent research in range ecology suggests that the process of resource degradation in African arid and semi-arid rangelands may be less reliant on how many animals are kept on the rangeland than on where these animals are kept. Analysis of pastoralist land use decisions indicated that rangeland condition influences livestock keeping. However, it was found that food and income production strategies, herd characteristics play critical roles in livestock keeping decisions
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Reinhardt, K.; McAbee, K.; Germino, M. J.; Bosworth, A.
2016-12-01
Semi-arid rangelands have been identified as potential carbon (C) sinks. However, the degree of net C storage or release in water-limited systems is a function of precipitation amount and timing, as well as plant community composition. In northern latitudes of western North America, climate models predict increases in wintertime precipitation and decreases in summertime precipitation. In theory, this should boost C storage in cold-desert ecosystems that have deep-rooted woody plants due to greater wintertime soil water storage that enhances summertime productivity. However, there are few long-term, manipulative field-based studies investigating how shrub- and grass-dominated rangelands will respond to changing precipitation patterns. We measured aboveground C pools and fluxes at leaf, soil, and ecosystem scales over the 2014 growing season on plots that had supplemental precipitation added in either winter or summer for 21 years, in shrub- and exotic-bunchgrass-dominated plots. We hypothesized that increased winter precipitation would stimulate aboveground C uptake and storage relative to ambient conditions, in our cold-desert-adapted plant species. We further hypothesized that long-term gains in aboveground C storage due to precipitation manipulations would be greater in plots containing shrubs. Our hypotheses were generally supported: ecosystem C uptake and long-term biomass accumulation were greater in winter- and summer-irrigated plots compared to control plots in both vegetation communities. However, substantial increases in aboveground biomass occurred only in winter-irrigated plots that contained shrubs. Our findings suggest that increases in winter precipitation will enhance C storage of this widespread ecosystem, provided that the ecosystems have resisted conversion to exotic grassland.
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A Dynamic Model of California's Hardwood Rangelands
Richard B. Standiford; Richard E. Howitt
1991-01-01
Low profitability of hardwood rangeland management, and oak tree harvesting for firewood markets and forage enhancement has led to concern about the long-term sustainability of the oak resource on rangelands. New markets for recreational hunting may give value to oaks for the habitat they provide for game species, and broaden the economic base for managers. A ranch...
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State-and-transition model archetypes: a global taxonomy of rangeland change
State and transition models (STMs) synthesize science-based and local knowledge to formally represent the dynamics of rangeland and other ecosystems. Mental models or concepts of ecosystem dynamics implicitly underlie all management decisions in rangelands and thus how people influence rangeland sus...
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Sustaining working rangelands: Insights from rancher decision making
Grazed rangeland ecosystems encompass diverse global land resources, and are complex social-ecological systems from which society demands both goods (e.g., livestock and forage production) and services (e.g., abundant and high quality water). In the dialogue on rangeland conservation and sustainable...
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Terefe, A.; Ebro, A.; Tessema, Z.K.
2010-01-01
A study was undertaken in Hamer and Benna-Tsemay districts of the Southern Ethiopia with the objective to determine the condition of the rangelands for grazing animals as influenced by altitude and grazing types. The rangelands in each of the study districts were stratified based on altitude and
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CSIR Research Space (South Africa)
Munyati, C
2013-07-01
Full Text Available The proliferation of woody plant species on savanna rangelands (i.e. bush encroachment) degrades rangeland quality, thereby threatening the biodiversity conservation effort as well as pastoral farming. Hyperspectral remote sensing offers...
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Adaptive management for complex communal rangelands in South ...
African Journals Online (AJOL)
Many of the intransigent problems facing the world arise in complex systems. In this paper, I propose that communal rangelands in South Africa be recognised as complex social–ecological systems and that one of the reasons that development initiatives have had little impact on improving livelihoods and rangeland ...
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Criterion IV: Social and economic indicators of rangeland sustainability (Chapter 5)
Daniel W. McCollum; Louis E. Swanson; John A. Tanaka; Mark W. Brunson; Aaron J. Harp; L. Allen Torell; H. Theodore Heintz
2010-01-01
Social and economic systems provide the context and rationale for rangeland management. Sustaining rangeland ecosystems requires attention to the social and economic conditions that accompany the functioning of those systems. We present and discuss economic and social indicators for rangeland sustainability. A brief conceptual basis for each indicator is offered,...
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William E. Fox; Daniel W. McCollum; John E. Mitchell; Louis E. Swanson; Urs P. Kreuter; John A. Tanaka; Gary R. Evans; H. Theodore Heintz; Robert P. Breckenridge; Paul H. Geissler
2009-01-01
Currently, there is no standard method to assess the complex systems in rangeland ecosystems. Decision makers need baselines to create a common language of current rangeland conditions and standards for continued rangeland assessment. The Sustainable Rangeland Roundtable (SRR), a group of private and public organizations and agencies, has created a forum to discuss...
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Water conservation for semi-arid rangelands
International Nuclear Information System (INIS)
Willis, W.O.
1983-01-01
Water deficiency is most often the cause for low forage production on rangelands in semi-arid and arid regions. Water conservation methods have been developed but additional research is needed to develop the best management practices for various climatic regions. Poor management is another major cause of low rangeland production. Better management, including the application of research findings, depends on attitudes, policies, adaptability of findings, resources for implementation and a good understanding of the governing biotic and abiotic factors. (author)
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Energy budgets and resistances to energy transport in sparsely vegetated rangeland
Nichols, W.D.
1992-01-01
Partitioning available energy between plants and bare soil in sparsely vegetated rangelands will allow hydrologists and others to gain a greater understanding of water use by native vegetation, especially phreatophytes. Standard methods of conducting energy budget studies result in measurements of latent and sensible heat fluxes above the plant canopy which therefore include the energy fluxes from both the canopy and the soil. One-dimensional theoretical numerical models have been proposed recently for the partitioning of energy in sparse crops. Bowen ratio and other micrometeorological data collected over phreatophytes growing in areas of shallow ground water in central Nevada were used to evaluate the feasibility of using these models, which are based on surface and within-canopy aerodynamic resistances, to determine heat and water vapor transport in sparsely vegetated rangelands. The models appear to provide reasonably good estimates of sensible heat flux from the soil and latent heat flux from the canopy. Estimates of latent heat flux from the soil were less satisfactory. Sensible heat flux from the canopy was not well predicted by the present resistance formulations. Also, estimates of total above-canopy fluxes were not satisfactory when using a single value for above-canopy bulk aerodynamic resistance. ?? 1992.
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Kerns, B. K.; Kim, J. B.; Day, M. A.; Pitts, B.; Drapek, R. J.
2017-12-01
Ecosystem process models are increasingly being used in regional assessments to explore potential changes in future vegetation and NPP due to climate change. We use the dynamic global vegetation model MAPSS-Century 2 (MC2) as one line of evidence for regional climate change vulnerability assessments for the US Forest Service, focusing our fine tuning model calibration from observational sources related to forest vegetation. However, there is much interest in understanding projected changes for arid rangelands in the western US such as grasslands, shrublands, and woodlands. Rangelands provide many ecosystem service benefits and local rural human community sustainability, habitat for threatened and endangered species, and are threatened by annual grass invasion. Past work suggested MC2 performance related to arid rangeland plant functional types (PFT's) was poor, and the model has difficulty distinguishing annual versus perennial grasslands. Our objectives are to increase the model performance for rangeland simulations and explore the potential for splitting the grass plant functional type into annual and perennial. We used the tri-state Blue Mountain Ecoregion as our study area and maps of potential vegetation from interpolated ground data, the National Land Cover Data Database, and ancillary NPP data derived from the MODIS satellite. MC2 historical simulations for the area overestimated woodland occurrence and underestimated shrubland and grassland PFT's. The spatial location of the rangeland PFT's also often did not align well with observational data. While some disagreement may be due to differences in the respective classification rules, the errors are largely linked to MC2's tree and grass biogeography and physiology algorithms. Presently, only grass and forest productivity measures and carbon stocks are used to distinguish PFT's. MC2 grass and tree productivity simulation is problematic, in particular grass seasonal phenology in relation to seasonal patterns
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Future scenarios of impacts to ecosystem services on California rangelands
Byrd, Kristin; Alvarez, Pelayo; Flint, Lorraine; Flint, Alan
2014-01-01
The 18 million acres of rangelands in the Central Valley of California provide multiple benefits or “ecosystem services” to people—including wildlife habitat, water supply, open space, recreation, and cultural resources. Most of this land is privately owned and managed for livestock production. These rangelands are vulnerable to land-use conversion and climate change. To help resource managers assess the impacts of land-use change and climate change, U.S. Geological Survey scientists and their cooperators developed scenarios to quantify and map changes to three main rangeland ecosystem services—wildlife habitat, water supply, and carbon sequestration. Project results will help prioritize strategies to conserve these rangelands and the ecosystem services that they provide.
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PERSPECTIVES ON RANGELAND ECOLOGY AND MANAGEMENT
Heady, Harold F.
2011-01-01
This paper reviews changes in rangeland ecology and management in the U.S.A. over the last 65 years and speculates on future changes. Emphasis has shifted from livestock management to ecological and environmental concerns, hence "rangeland ecology." The term "range management" may have outlived its usefulness and may also be detrimental to our image. The vision that we have of ourselves is not the same as others have of us. Many members of the Society for Range Management (SRM) and most of ou...
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Stanford A. Young; Jason Vernon; Nancy Shaw
2013-01-01
Basin wildrye (Leymus cinereus [Scribn. & Merr.] A. Love) is an important perennial, hardy, long-lived, cool season C3 native grass of rangeland plant communities throughout much of western United States and Canada. All classes of livestock and wildlife, including large and small birds and mammals, utilise the grass year round for food and protection due to its 2-3...
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African Journals Online (AJOL)
Session B3 Management for sustainable use — Rangeland and water resources. ... The theme of optimsing integrated catchment management will be treated ... land system, catchment, basin), with a focus on law, policy and implementation.
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Meeting wild bees' needs on Western US rangelands
James H. Cane
2011-01-01
Rangelands are areas that are too arid, or with soils too shallow, to support either forests or cultivated agriculture, but that nonetheless produce enough vegetation for livestock grazing. Some arid rangeland regions, notably those with warm, dry climates in temperate zones (e.g., the warm deserts of the United States and adjacent Mexico, parts of Australia, South...
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Daniel W. McCollum; H. Theodore Jr. Heintz; Aaron J. Harp; John A. Tanaka; Gary R. Evans; David Radloff; Louis E. Swanson; William E. III Fox; Michael G. Sherm Karl; John E. Mitchell
2006-01-01
Use and sustainability of rangelands are inherently linked to the health and sustainability of the land. They are also inherently linked to the social and economic infrastructures that complement and support those rangelands and rangeland uses. Ecological systems and processes provide the biological interactions underlying ecosystem health and viability. Social and...
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Ecohydrologic impacts of rangeland fire on runoff and erosion: A literature synthesis
Frederick B. Pierson; C. Jason Williams
2016-01-01
Fire can dramatically influence rangeland hydrology and erosion by altering ecohydrologic relationships. This synthesis presents an ecohydrologic perspective on the effects of fire on rangeland runoff and erosion through a review of scientific literature spanning many decades. The objectives are: (1) to introduce rangeland hydrology and erosion concepts necessary for...
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A description of rangeland on commercial and communal land ...
African Journals Online (AJOL)
Analysis of a Landsat TM image from a rangeland near Peddie, Eastern Cape, revealed differences in two vegetation indices (normalised difference vegetation index, NDVI, and moving standard deviation index, MSDI) between communal and commercial rangeland. It was suggested that the difference in the MSDI reflected ...
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Bio solids Effects in Chihuahuan Desert Rangelands: A Ten-Year Study
International Nuclear Information System (INIS)
Wester, D.B; Sosebee, R.E; Fish, E.B; Villalobos, J.C; Zartman, R.E; Gonzalez, R.M; Jurado, P.; Moffet, C.A
2011-01-01
Arid and semiarid rangelands are suitable for responsible bio solids application. Topical application is critical to avoid soil and vegetation disturbance. Surface-applied bio solids have long-lasting effects in these ecosystems. We conducted a 10-year research program investigating effects of bio solids applied at rates from 0 to 90 dry Mg ha -1 on soil water infiltration; runoff and leachate water quality; soil erosion; forage production and quality; seedling establishment; plant physiological responses; nitrogen dynamics; bio solids decomposition; and grazing animal behavior and management. Bio solids increased soil water infiltration and reduced erosion. Effects on soil water quality were observed only at the highest application rates. Bio solids increased soil nitrate-nitrogen. Bio solids increased forage production and improved forage quality. Bio solids increased leaf area of grasses; photosynthetic rates were not necessarily increased by bio solids. Bio solids effects on plant establishment are expected only under moderately favorable conditions. Over an 82-mo exposure period, total organic carbon, nitrogen, and total and available phosphorus decreased and inorganic matter increased. Grazing animals spent more time grazing, ruminating, and resting in bio solids-treated areas; positive effects on average daily gain were observed during periods of higher rainfall. Our results suggest that annual bio solids application rates of up to 18 Mg ha -1 are appropriate for desert rangelands.
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Managing the livestock– Wildlife interface on rangelands
du Toit, Johan T.; Cross, Paul C.; Valeix, Marion
2017-01-01
On rangelands the livestock–wildlife interface is mostly characterized by management actions aimed at controlling problems associated with competition, disease, and depredation. Wildlife communities (especially the large vertebrate species) are typically incompatible with agricultural development because the opportunity costs of wildlife conservation are unaffordable except in arid and semi-arid regions. Ecological factors including the provision of supplementary food and water for livestock, together with the persecution of large predators, result in livestock replacing wildlife at biomass densities far exceeding those of indigenous ungulates. Diseases are difficult to eradicate from free-ranging wildlife populations and so veterinary controls usually focus on separating commercial livestock herds from wildlife. Persecution of large carnivores due to their depredation of livestock has caused the virtual eradication of apex predators from most rangelands. However, recent research points to a broad range of solutions to reduce conflict at the livestock–wildlife interface. Conserving wildlife bolsters the adaptive capacity of a rangeland by providing stakeholders with options for dealing with environmental change. This is contingent upon local communities being empowered to benefit directly from their wildlife resources within a management framework that integrates land-use sectors at the landscape scale. As rangelands undergo irreversible changes caused by species invasions and climate forcings, the future perspective favors a proactive shift in attitude towards the livestock–wildlife interface, from problem control to asset management.
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Managing climate change risks in rangeland systems [Chapter 15
Linda A. Joyce; Nadine A. Marshall
2017-01-01
The management of rangelands has long involved adapting to climate variability to ensure that economic enterprises remain viable and ecosystems sustainable; climate change brings the potential for change that surpasses the experience of humans within rangeland systems. Adaptation will require an intentionality to address the effects of climate change. Knowledge of...
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Carneggie, D. M.; Degloria, S. D.
1972-01-01
The author has identified the following significant results. Preliminary analysis of ERTS-1 MSS imagery of annual and perennial rangeland in California yields the following observations: (1) Sufficient geomorphological detail can be resolved to differentiate upland and bottomland range sites in the foothill range areas. (2) Dry and green meadowland can be differentiated on MSS band 5. (3) Color composites prepared by NASA-Goddard were useful for locating perennial rangeland with varying amounts of herbaceous ground cover. (4) The ERTS-1 images received and interpreted cover nearly 50% of the state of California and show nearly two-thirds of the annual grassland type. (5) Satellite imagery obtained during the late summer season should be optimum for differentiating grassland from brushland and forested land. (6) The ERTS-1 imagery clearly shows areas which at one time were part of the annual grassland but which are now used for dry land farming (cropping of cereal grains). Similarly, the imagery show areas which have been converted from brushland to grassland.
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Directory of Open Access Journals (Sweden)
Ammon Boswell
2017-01-01
Full Text Available Rangeland monitoring is important for evaluating and assessing semi-arid plant communities. Remote sensing provides an effective tool for rapidly and accurately assessing rangeland vegetation and other surface attributes such as bare soil and rock. The purpose of this study was to evaluate the efficacy of remote sensing as a surrogate for field-based sampling techniques in detecting ground cover features (i.e., trees, shrubs, herbaceous cover, litter, surface, and comparing results with field-based measurements collected by the Utah Division of Wildlife Resources Range Trent Program. In the field, five 152 m long transects were used to sample plant, litter, rock, and bare-ground cover using the Daubenmire ocular estimate method. At the same location of each field plot, a 4-band (R,G,B,NIR, 25 cm pixel resolution, remotely sensed image was taken from a fixed-wing aircraft. Each image was spectrally classified producing 4 cover classes (tree, shrub, herbaceous, surface. No significant differences were detected between canopy cover collected remotely and in the field for tree (P = 0.652, shrub (P = 0.800, and herbaceous vegetation (P = 0.258. Surface cover was higher in field plots (P < 0.001, likely in response to the methods used to sample surface features by field crews. Accurately classifying vegetation and other features from remote sensed information can improve the efficiency of collecting vegetation and surface data. This information can also be used to improve data collection frequency for rangeland monitoring and to efficiently quantify ecological succession patterns.
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The Role of Rural Communities in Conservation of Rangelands in Mahneshan Township
Directory of Open Access Journals (Sweden)
Kobra Karimi
2016-05-01
Full Text Available The aim of this study was to investigate the action of rangeland-depended livestock holders regarding rangeland conservation, including protection and rehabilitation activities and to analyse relevant influencing factors, using a mixed method of survey and case study. The data were collected through analysing existing documents, focus groups, semi-structured and structured interviews using questionnaires submitted to 204 rural livestock holders in the Mahneshan Township. The quantitative data were analysed using SPSS and AMOS software. According to the results farmers’ knowledge regarding the role, importance and factors affecting rangeland degradation was relatively high, however they had a low level of knowledge and action about mechanical conservation techniques. The action of livestock holders in terms of biological conservation activities and grazing management showed a positive and signifincat corrletaion with variables such as implementing of rangeland projects, their interaction with external institutions, participating in extension training courses, education level and irrigated and rainfed agricultural land size. Moreover, based on a path analysis, 37% of the variance of the farmers’ actions regarding the rangeland conservation was explained by the variables such as rangeland rehabilitation actions, farmers’ conservation knowledge, farmers’ interaction with natural resources experts, beekeeping, and participating in extension training courses. Promotional and extension activities and farmers’ interaction with experts have a positive effect in enhancing farmers’ knowledge and actions for sustainable rangeland use and conservation.
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The GEOGLAM Rangelands and Pasture Productivity Activity: Recent Progress and Future Directions
Guerschman, J. P.; Held, A. A.; Donohue, R. J.; Renzullo, L. J.; Sims, N.; Kerblat, F.; Grundy, M.
2015-12-01
Rangelands and pastures cover about a third of the world's land area and support livestock production which represents ~40% of global agricultural gross domestic product. The global consumption of animal protein shows a clear increasing trend, driven by both total population and per capita income increases, putting a growing pressure on the sustainability of grazing lands worldwide. Despite their relevance, rangelands have received less attention than croplands regarding global monitoring of the resource productivity and condition. The Rangelands and Pasture Productivity (RaPP) activity is a component within the Global Agricultural Monitoring initiative established under the Group on Earth Observations (GEOGLAM) in 2013. GEOGLAM RaPP is aimed at providing the global community with the means to monitor the world's rangelands and pastures on a routine basis, and the capacity to produce animal protein in real-time, at global, regional and national levels. Since its launch two years ago GEOGLAM RAPP has made progress in the four implementation elements. These include: 1- the establishment of community of practice; 2- the development of a global monitoring system for rangeland condition; 3- the establishment of pilot sites in main rangeland systems for satellite data products validation and model testing; and 4- integration with livestock production models. Three international workshops have been held building the community of practice. A prototype monitoring system that provides global visualisations and querying capability of vegetation cover data and anomalies has been established. Pilot sites, mostly in areas with long records of field measurements of rangeland condition and productivity have been proposed for nine countries. The link to global livestock models, including physical and economic components, have been established. Future challenges for GEOGLAM RaPP have also been identified and include: better representation of the areas occupied by rangelands
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Ecological evaluation of rangeland quality in dry subtropics of Azerbaijan
Gasanova, A. F.
2014-12-01
The results of ecological evaluation of soil-landscape complexes of winter rangelands of Gobustan with the use of energy criteria are discussed. The diagnostic characteristics of soil fertility and correction coefficients for the thickness of texture of soil horizons, soil salinization, soil erosion, and microelemental composition of soils have been used to separate the soils of winter rangelands into several quality groups. A larger part of the soils belongs to the medium quality group with the mean weighted quality factor (bonitet) of 52. Special assessment scales have been suggested for the differential ecological assessment and monitoring of the rangelands. In the past 40 years, the area of steppe landscapes has decreased from 22.7 to 12%, whereas the area of semideserts has increased up to 64%. The area of best-quality soils within the studied rangelands had decreased by three times, and their average quality factor has decreased from 92 to 86.
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Rangeland -- Plant response to elevated CO{sub 2}. Progress report
Energy Technology Data Exchange (ETDEWEB)
NONE
1996-08-01
An experiment is being designed to examine the influence of elevating CO2 levels on tallgrass prairie rangeland. Changes in biomass production, photosynthesis rates, and species composition (C3 versus C4) over time are to be examined. This report covers the period from August 15, 1988 to January 1, 1989. During this period the authors have had planning meetings in Manhattan, KS, and Washington, DC, with various investigators of the measurement and modeling groups within the elevated CO{sub 2} program. During this period detailed discussions with regard to the methodology were carried out. In addition, short-term experiments and prototype constructions were completed to assess design and materials. Because of changes in the methodology and, to a certain degree, the scope, they are requesting changes in the funding cycle to implement the project at the beginning of the growing cycle of the tallgrass prairie.
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Very High Resolution Panoramic Photography to Improve Conventional Rangeland Monitoring 1994
Rangeland monitoring often includes repeat photographs as a basis for documentation and although photographic equipment and electronics have been evolving rapidly, basic rangeland photo monitoring methods have changed little over time. Ground based digital photography is underutilized, especially s...
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1996-01-01
In August 1995, new BLM regulations for rangeland administration went into effect. The new regulations require BLM to establish regional standards for rangeland health and guidelines for grazing management. This publication is a report on the alternatives being considered for the Montana/Dakotas Rangeland Health Standards and Guidelines process.
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Fodder Biomass Monitoring in Sahelian Rangelands Using Phenological Metrics from FAPAR Time Series
Directory of Open Access Journals (Sweden)
Abdoul Aziz Diouf
2015-07-01
Full Text Available Timely monitoring of plant biomass is critical for the management of forage resources in Sahelian rangelands. The estimation of annual biomass production in the Sahel is based on a simple relationship between satellite annual Normalized Difference Vegetation Index (NDVI and in situ biomass data. This study proposes a new methodology using multi-linear models between phenological metrics from the SPOT-VEGETATION time series of Fraction of Absorbed Photosynthetically Active Radiation (FAPAR and in situ biomass. A model with three variables—large seasonal integral (LINTG, length of growing season, and end of season decreasing rate—performed best (MAE = 605 kg·DM/ha; R2 = 0.68 across Sahelian ecosystems in Senegal (data for the period 1999–2013. A model with annual maximum (PEAK and start date of season showed similar performances (MAE = 625 kg·DM/ha; R2 = 0.64, allowing a timely estimation of forage availability. The subdivision of the study area in ecoregions increased overall accuracy (MAE = 489.21 kg·DM/ha; R2 = 0.77, indicating that a relation between metrics and ecosystem properties exists. LINTG was the main explanatory variable for woody rangelands with high leaf biomass, whereas for areas dominated by herbaceous vegetation, it was the PEAK metric. The proposed approach outperformed the established biomass NDVI-based product (MAE = 818 kg·DM/ha and R2 = 0.51 and should improve the operational monitoring of forage resources in Sahelian rangelands.
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Emerging issues and challenges in conservation of biodiversity in the rangelands of Tanzania
Directory of Open Access Journals (Sweden)
Jafari Kideghesho
2013-11-01
Full Text Available Tanzania rangelands are a stronghold for biodiversity harbouring a variety of animal and plant species of economic, ecological and socio-cultural importance. Efforts to protect these resources against destruction and loss have involved, among other things, setting aside some tracks of land as protected areas in the form of national parks, nature reserves, game reserves, game controlled and wildlife management areas. However, these areas and adjacent lands have long been subjected to a number of emerging issues and challenges, which complicate their management, thus putting the resources at risk of over exploitation and extinction. These issues and challenges include, among other things, government policies, failure of conservation (as a form of land use to compete effectively with alternative land uses, habitat degradation and blockage of wildlife corridors, overexploitation and illegal resource extraction, wildfires, human population growth, poverty, HIV/AIDS pandemic and human-wildlife conflicts. In this paper, we review the emerging issues and challenges in biodiversity conservation by drawing experience from different parts of Tanzania. The paper is based on the premise that, understanding of the issues and challenges underpinning the rangelands is a crucial step towards setting up of plausible objectives, strategies and plans that will improve and lead to effective management of these areas. We conclude by recommending some proactive measures that may enhance the sustainability of the rangeland resources for the benefit of the current and future generations.
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Earth stewardship on rangelands: Coping with ecological, economic, and political marginality
Rangelands encompass 30-40 percent of Earth's land surface and support 1-2 billion people. Their predominant use is extensive livestock production by pastoralists and ranchers. But rangelands are characterized by ecological, economic, and political marginality, and higher-value, more intensive land ...
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Discussion of submitted posters for Section 2.3 (Rangeland Germplasm Resources)
As part of the IX International Rangeland Congress held in Rosario, Argentina, a total of 70 posters from 17 countries were submitted to Section 2.3 (Rangeland Germplasm Resources). These posters documented research conducted in five major regions of the world: South America, North America, Africa...
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Current stage of the restoration of Chernozems in rangeland ecosystems of the steppe zone
Rusanov, A. M.
2015-06-01
The results of two rounds of soil and geobotanic surveys of rangeland ecosystems in the steppe zone are presented. The same sites with southern chernozems (Calcic Chernozems) under steppe plant communities at different stages of pasture degradation were investigated at the end of the 1980s, when they suffered maximum anthropogenic loads, and in 2011-2013, after a long period of relative rest. In the 1980s, degradation of soil physical properties in rangeland ecosystems under the impact of long-term unsustainable management was noted. At the same time, it was found that the major qualitative and quantitative properties of humus in the chernozems were preserved independently from the level of pasture degradation. The following period of moderate grazing pressure had a favorable effect on the soil properties. Owing to the good characteristics of the soil humus, the restoration of the physical properties of chernozems-including their structural state, water permeability, and bulk density-took place in a relatively short period. It is argued that the soil bulk density is a natural regulator of the species composition of steppe vegetation, because true grasses (Poaceae)-typical representatives of the steppe flora-have a fibrous root system requiring the soils with low density values. The improvement of the properties of chernozems is related to the development of secondary ecosystems with a higher portion of grasses in place of damaged rangelands and to the increase in the area of nominal virgin phytocenoses.
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Climate change effects on rangelands and rangeland management: Affirming the need for monitoring
Daniel W. Mccollum; John A. Tanaka; Jack A. Morgan; John E. Mitchell; William E. Fox; Kristie A. Maczko; Lori Hidinger; Clifford S. Duke; Urs P. Kreuter
2017-01-01
Uncertainty as to the extent and magnitude of changes in conditions that might occur due to climate change poses a problem for land and resource managers as they seek to adapt to changes and mitigate effects of climate variability. We illustrate using scenarios of projected future conditions on rangelands in the Northern Great Plains and Desert Southwest of the United...
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Jeremy J. James; Tony Svejcar
2010-01-01
Seeding rangeland following wildfire is a central tool managers use to stabilize soils and inhibit the spread of invasive plants. Rates of successful seeding on arid rangeland, however, are low. The objective of this study was to determine the degree to which water availability, invasive plant abundance, and seeding technology influence postfire seedling establishment...
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CSIR Research Space (South Africa)
Dube, S
2010-07-01
Full Text Available Communal area rangeland resource users are an important part of the rangeland ecosystem; rangeland management policies and practice should, therefore, accommodate their socio-cultural practices and knowledge. Indigenous knowledge (IK) is often...
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Tsalyuk, Miriam
2014-01-01
Rangelands cover about half of Earth's land surface, encompass considerable biodiversity, and provide pivotal ecosystem services. However, rangelands across the globe face degradation due to changes in climate, land use, and management. Moreover, since herbivory is fundamental to rangeland ecosystem dynamics, shifts in the distribution of herbivores lead to overgrazing and desertification. To better understand, predict, and prevent changes on rangelands it is important to monitor these landsc...
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Climate change and North American rangelands: Assessment of mitigation and adaptation strategies
Linda A. Joyce; David D. Briske; Joel R. Brown; H. Wayne Polley; Bruce A. McCarl; Derek W. Bailey
2013-01-01
Recent climatic trends and climate model projections indicate that climate change will modify rangeland ecosystem functions and the services and livelihoods that they provision. Recent history has demonstrated that climatic variability has a strong influence on both ecological and social components of rangeland systems and that these systems possess substantial...
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Liu, H.; Jin, Y.; Devine, S.; Dahlgren, R. A.; Covello, S.; Larsen, R.; O'Geen, A. T.
2017-12-01
California rangelands cover 23 million hectares and support a $3.4 billion annual cattle industry. Rangeland forage production varies appreciably from year-to-year and across short distances on the landscape. Spatially explicit and near real-time information on forage production at a high resolution is critical for effective rangeland management, especially during an era of climatic extremes. We here integrated a multispectral MicaSense RedEdge camera with a 3DR solo quad-copter and acquired time-series images during the 2017 growing season over a topographically complex 10-hectare rangeland in San Luis Obispo County, CA. Soil moisture and temperature sensors were installed at 16 landscape positions, and vegetation clippings were collected at 36 plots to quantify forage dry biomass. We built four centimeter-level models for forage production mapping using time series of sUAS images and ground measurements of forage biomass and soil temperature and moisture. The biophysical model based on Monteith's eco-physiological plant growth theory estimated forage production reasonably well with a coefficient of determination (R2) of 0.86 and a root-mean-square error (RMSE) of 424 kg/ha when the soil parameters were included, and a R2 of 0.79 and a RMSE of 510 kg/ha when only remote sensing and topographical variables were included. We built two empirical models of forage production using a stepwise variable selection technique, one with soil variables. Results showed that cumulative absorbed photosynthetically active radiation (APAR) and elevation were the most important variables in both models, explaining more than 40% of the spatio-temporal variance in forage production. Soil moisture accounted for an additional 29% of the variance. Illumination condition was selected as a proxy for soil moisture in the model without soil variables, and accounted for 18% of the variance. We applied the remote sensing-based models to map daily forage production at 30-cm resolution for the
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Admasu, T.; Abule, E.; Tessema, Z.K.
2010-01-01
A survey was conducted in Hamer and Benna-Tsemay districts of the South Omo zone of Ethiopia, with the objectives of assessing the range-livestock management practices and perceptions of the different pastoral groups (Hamer, Benna, and Tsemay) towards rangeland degradation. This information is
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Continuous population growth, recent refugee movement and migration as well as boundary restrictions and their implications on the nomadic lifestyle are additive pressure on rangelands throughout the Middle East. In particular, overgrazing through increased livestock herds threatens the Jordanian ra...
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Rangeland Use Rights Privatisation Based on the Tragedy of the Commons: A Case Study from Tibet
Directory of Open Access Journals (Sweden)
Yonten Nyima Yundannima
2017-01-01
Full Text Available Rangeland use rights privatisation based on a tragedy of the commons assumption has been the backbone of state policy on rangeland management and pastoralism in China. Through an empirical case study from Pelgon county, Tibet Autonomous Region in China, this paper provides an empirical analysis of rangeland use rights privatisation. It shows that the tragedy of the commons is not the correct model to apply to Tibetan pastoralism because pasture use in Tibet has never been an open-access institution. Thus, when the tragedy of the commons model is applied as a rationale for rangeland use rights privatisation, the result is not what is intended by the policy, but rather a misfit to features of pastoralism and thus disruption of the essence of pastoralism, i.e. mobility and flexibility. The paper further shows that a hybrid institution combining household rangeland tenure with community-based use with user fees is a restoration of the pastoralist institution. This demonstrates the capacity of pastoralists to create adaptive new institutions congruent with the interdependent and integrated nature of pastoralism consisting of three components: pastoralists, livestock, and rangeland.
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Global view of remote sensing of rangelands: Evolution, applications, future pathways [Chapter 10
Matt Reeves; Robert A. Washington-Allen; Jay Angerer; E. Raymond Hunt; Ranjani Wasantha Kulawardhana; Lalit Kumar; Tatiana Loboda; Thomas Loveland; Graciela Metternicht; R. Douglas. Ramsey
2015-01-01
The term "rangeland" is rather nebulous, and there is no single definition of rangeland that is universally accepted by land managers, scientists, or international bodies (Lund, 2007; Reeves and Mitchell, 2011). Dozens and possibly hundreds (Lund, 2007) of definitions and ideologies exist because various stakeholders often have unique objectives...
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Resource analysis of the Chinese society 1980-2002 based on exergy-Part 4: Fishery and rangeland
International Nuclear Information System (INIS)
Chen, B.; Chen, G.Q.
2007-01-01
This fourth part is the continuation of the third part on agricultural products. The major fishery and rangeland products entering the Chinese society from 1980 to 2002 are calculated and analyzed in detail in this paper. The aquatic production, mainly relying on freshwater and seawater breeding, Enhancement policy of fishery resources, including closed fishing season system, construction of artificial fish reefs and ecological fish breeding, etc., is discussed in detail. The degradation of the major rangeland areas, hay yields and intake rangeland resources by the livestock, are also described associated with the strategic adjustment and comprehensive program to protect rangeland resources during the study period
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Rangeland fire is a common naturally occurring event and management tool, with the amount and structure of biomass controlling transfer of heat belowground. Temperatures grasshopper eggs are exposed to during rangeland fires are mediated by species specific oviposition traits. This experiment examin...
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Bayesian estimation of shrubs diversity in rangelands under two management systems in northern Syria
Niane, A.A.; Singh, M.; Struik, P.C.
2014-01-01
The diversity of shrubs in rangelands of northern Syria is affected by the grazing management systems restricted by the increase in human and livestock populations. To describe and estimate diversity and compare the rangeland grazing management treatments, two popular indices for diversity, the
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Elevated carbon dioxide: impacts on soil and plant water relations
National Research Council Canada - National Science Library
Kirkham, M. B
2011-01-01
.... Focusing on this critical issue, Elevated Carbon Dioxide: Impacts on Soil and Plant Water Relations presents research conducted on field-grown sorghum, winter wheat, and rangeland plants under elevated CO2...
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Management of Collective Rangelands in Rhamna (Morocco ...
International Development Research Centre (IDRC) Digital Library (Canada)
Management of Collective Rangelands in Rhamna (Morocco) ... reduce the pressure on natural resources and promote sustainable management. ... Project status ... IDRC congratulates first cohort of Women in Climate Change Science Fellows ... and adaptive water management: Innovative solutions from the Global South”.
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World Bank
2005-01-01
Pastoralists' indigenous knowledge (IK) about ecology and social organization led to rangeland-management strategies appropriate to deal with the erratic rainfall in African drylands. Herd mobility was traditionally practiced as the key strategy to make use of the scattered rangeland resources on a large scale.
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Botanical Criteria of Baharkish Rangeland in Quchan, Khorasan ...
African Journals Online (AJOL)
ADOWIE PERE
University of Mashhad International Campus, Mashhad, I.R of IRAN ... ABSTRACT: Rangelands are natural ecosystems containing a range of resources of genetic ..... Ecology of world vegetation. .... Science Journal of Islamic Azad University,.
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Rangelands comprise approximately 40% of the earth’s surface and are the largest land cover type in the world. Degradation from mismanagement, desertification, and drought impact more than 50% of rangelands across the globe. The USDA Agricultural Research Service (ARS) has been evaluating means of r...
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International Nuclear Information System (INIS)
Nasyrov, M.G.; Safarov, A.N.; Osmanov, B.S.
2004-01-01
Full text: Desertification and land degradation are a problem of major importance in the arid and semi-arid regions of the world. Deterioration of soil and plant cover has adversely affected nearly 50% of land areas as a result of extended droughts and human mismanagement of cultivated and rangelands. Due to several factors such as soil erosion, overgrazing, collection of plants and other anthropogenic activities the most part of these biomes are under degradation. The problem of assessments of current status of rangelands becomes very important days after days. Therefore, it needs to work out and implement new time and labor saving methods of assessment of current status of natural biomes. Soil erosion is a natural process caused by water, wind, and ice that have affected the earth's surface since the beginning if time. Man's activities often accelerate soil erosion. Soil erosion and its off-site, downstream damages are major concerns around the world causing losses in soil productivity, degradation of landscape, degradation of water quality, and loss of soil organic carbon. Current techniques for assessing soil erosion are (1) long-term soil erosion plot monitoring, (2) field surveys, and (3) soil erosion models (Evans, 1995). Each of this techniques has strengths and weaknesses. Over the last 30 years, research has shown the potential of using radioactive fallout 137 Cs to provide timely and quantitative estimates of soil erosion and redeposition at point, field, and reconnaissance scales. Applications of 137 Cs o provide an independent measurement of soil erosion rates, patterns, and redepositions are well-documented (Ritchie and McHenry, 1990). The unique advantages of the 137 Cs technique to study soil erosion rates and patterns are that it (a) requires only one trip to the field; (b) provides results quickly; (c) allows retrospective assessment of soil erosion rates; (d) provides average losses for 35 to 40 year period thus is less influenced by extreme
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John E. Mitchell
2000-01-01
This report documents trends in America's rangelands as required by the Renewable Resources Planning Act of 1974. The Forest Service has conducted assessments of the rangeland situation for 30 years. Over this period, rangeland values and uses have gradually shifted from concentrating upon forage production and meeting increasing demand for red meat to a more...
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Rehabilitation of community-owned, mixed-use rangelands: Lessons from the Ewaso ecosystem in Kenya
Globally, 10-20% of arid and semi-arid rangelands have been classified as severely degraded (UNCCD 1994; MEA 2005), and in sub-Saharan Africa specifically, 70% of rangelands are considered moderately to severely degraded (Dregne 1992; UNCCD 1994). Given that these drylands make up 43% of Africa’s la...
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Recovery of rangelands : the functioning of soil seed banks in a semi-arid African savanna
Tessema, Z.K.
2011-01-01
Rangelands in Africa provide important forage resources for herbivores; particularly perennial grasses provide grazing for domestic and wild herbivores. However, semi-arid African rangelands experience severe vegetation and soil degradation due to heavy grazing, causing negative impacts
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Sugita, Michiaki; Asanuma, Jun; Tsujimura, Maki; Mariko, Shigeru; Lu, Minjiao; Kimura, Fujio; Azzaya, Dolgorsuren; Adyasuren, Tsokhio
2007-01-01
SummaryIntensive observations, analysis and modeling within the framework of the rangelands atmosphere-hydrosphere-biosphere interaction study experiment in northeastern Asia (RAISE) project, have allowed investigations into the hydrologic cycle in the ecotone of forest-steppe, and its relation to atmosphere and ecosystem in the eastern part of Mongolia. In this region, changes in the climate have been reported and a market oriented economy was introduced recently, but their impact on the natural environment is still not well understood. In this RAISE special issue, the outcome is presented of the studies carried out by six groups within RAISE, namely: (1) Land-atmosphere interaction analysis, (2) ecosystem analysis and modeling, (3) hydrologic cycle analysis, (4) climatic modeling, (5) hydrologic modeling, and (6) integration. The results are organized in five relevant categories comprising (i) hydrologic cycle including precipitation, groundwater, and surface water, (ii) hydrologic cycle and ecosystem, (iii) surface-atmosphere interaction, (iv) effect of grazing activities on soils, plant ecosystem and surface fluxes, and (v) future prediction. Comparison with studies on rangelands in other parts of the world, and some future directions of studies still needed in this region are also summarized.
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Clint Shock; Erik Feibert; Lamont Saunders; Nancy Shaw
2010-01-01
Seed of native plants is needed to restore rangelands of the Intermountain West. Reliable commercial seed production is desirable to provide the quantity of seed needed for restoration efforts. Establishment of native seed crops has been difficult, because fall-planted seed is susceptible to bird damage, soil crusting, and soil erosion. Fall planting is important for...
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CSIR Research Space (South Africa)
Lesoli, MS
2010-07-01
Full Text Available Rangeland degradation results in declining functional capacity, increased poverty, and food insecurity. Major changes in rangeland surface morphology and soil characteristics have a drastic effect on the primary productivity of the rangeland...
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Effects of climate change on rangeland vegetation in the Northern Rockies Region [Chapter 7
Matt C. Reeves; Mary E. Manning; Jeff P. DiBenedetto; Kyle A. Palmquist; William K. Lauenroth; John B. Bradford; Daniel R. Schlaepfer
2018-01-01
Rangelands are dominated by grass, forb, or shrub species, but are usually not modified by using agronomic improvements such as fertilization or irrigation (Lund 2007; Reeves and Mitchell 2011) as these lands would normally be considered pastures. Rangeland includes grassland, shrubland, and desert ecosystems, alpine areas, and some woodlands (box 7.1). This chapter...
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Berg, Matthew D.; Marcantonio, Franco; Allison, Mead A.; McAlister, Jason; Wilcox, Bradford P.; Fox, William E.
2016-06-01
Rangelands cover a large portion of the earth's land surface and are undergoing dramatic landscape changes. At the same time, these ecosystems face increasing expectations to meet growing water supply needs. To address major gaps in our understanding of rangeland hydrologic function, we investigated historical watershed-scale runoff and sediment yield in a dynamic landscape in central Texas, USA. We quantified the relationship between precipitation and runoff and analyzed reservoir sediment cores dated using cesium-137 and lead-210 radioisotopes. Local rainfall and streamflow showed no directional trend over a period of 85 years, resulting in a rainfall-runoff ratio that has been resilient to watershed changes. Reservoir sedimentation rates generally were higher before 1963, but have been much lower and very stable since that time. Our findings suggest that (1) rangeland water yields may be stable over long periods despite dramatic landscape changes while (2) these same landscape changes influence sediment yields that impact downstream reservoir storage. Relying on rangelands to meet water needs demands an understanding of how these dynamic landscapes function and a quantification of the physical processes at work.
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The increased role of wildland fire across the rangeland-dry forest continuum in the western United States (US) presents landscape-scale consequences relative runoff and erosion. Much of the Intermountain West now exists in a state in which rangeland and woodland wildfires stimulated by invasive che...
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Reed, M S; Stringer, L C; Dougill, A J; Perkins, J S; Atlhopheng, J R; Mulale, K; Favretto, N
2015-03-15
This paper identifies new ways of moving from land degradation towards sustainable land management through the development of economic mechanisms. It identifies new mechanisms to tackle land degradation based on retaining critical levels of natural capital whilst basing livelihoods on a wider range of ecosystem services. This is achieved through a case study analysis of the Kalahari rangelands in southwest Botswana. The paper first describes the socio-economic and ecological characteristics of the Kalahari rangelands and the types of land degradation taking place. It then focuses on bush encroachment as a way of exploring new economic instruments (e.g. Payments for Ecosystem Services) designed to enhance the flow of ecosystem services that support livelihoods in rangeland systems. It does this by evaluating the likely impacts of bush encroachment, one of the key forms of rangeland degradation, on a range of ecosystem services in three land tenure types (private fenced ranches, communal grazing areas and Wildlife Management Areas), before considering options for more sustainable land management in these systems. We argue that with adequate policy support, economic mechanisms could help reorient degraded rangelands towards more sustainable land management. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
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A comparison of the effects of different rangeland management ...
African Journals Online (AJOL)
A comparison of the effects of different rangeland management systems on ... Three management systems exploit these areas: commercial livestock ranching, communal livestock ranching and game ranching. ... AJOL African Journals Online.
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Grazing intensity on the plant diversity of alpine meadow in the eastern Tibetan plateau
Directory of Open Access Journals (Sweden)
Wu Ning
2004-04-01
Full Text Available Because ofthe remoteness and harsh conditions of the high-altitude rangelands on the eastern Tibetan Plateau, the relationship between yak grazing and plant diversity has not been so clear although livestock increase was thought as the main issue leading to the degradation of rangeland. In the debate of rangeland degradation, biodiversity loss has been assumed as one of the indicators in the last two decades. In this paper authors measured the effects of different grazing intensities on the plant diversity and the structure of Kobresia pygmaea community in the case-study area, northwestern Sichuan. The results indicated that plant diversity of alpine meadow has different changing trends respectively with the change of grazing intensity and seasons. In June the highest plant diversity occurred in the intensively grazed (HG plots, but in July and September species biodiversity index of slightly grazed (LG plots is higher than other experimental treatments. In August the intermediate grazed (IG plots has the highest biodiversity index. Moreover, it was found that intensively grazing always leads to the increase of plant density, but meanwhile the decrease of community height, coverage and biomass. Over-grazing can change the community structure and lead to the succession from Kobresia pygmaea dominated community to Poa pratensis dominated. Analyzing results comprehensively, it can be suggested that the relationship between grazing intensity and plant diversity is not linear, i.e. diversity index is not as good as other characteristics of community structure to evaluate rangeland degradation on the high altitude situation. The change of biodiversity is so complicated that it can not be explained with the simple corresponding causality.
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DEVELOPMENTS IN MONITORING RANGELANDS USING REMOTELY-SENSED CROSS-FENCE COMPARISONS
Directory of Open Access Journals (Sweden)
A. D. Kilpatrick
2012-07-01
Full Text Available This paper presents a new method for the use of earth-observation images to assess relative land condition over broad regions, using a cross-fence comparison methodology. It controls for natural spatial and temporal variables (e.g. rainfall, temperature soils, ecosystem so that we can objectively monitor rangelands and other areas for the effects of management. The method has been tested with small and large scale theoretical models, as well as a case study in South Australian rangelands. This method can also be applied in other systems and experiments such as field trials of crop varieties as a robust spatial statistic.
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Ho, P.P.S.
2000-01-01
China's economic reforms have exacerbated the problems of over-grazing and desertification in the country's pastoral areas. In order to deal with rangeland degradation, the Chinese government has resorted to nationalization, or semi-privatization. Since the implementation of rangeland policy has
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Forests, rangelands and climate change in Southern Africa
CSIR Research Space (South Africa)
Naidoo, Sasha
2013-09-01
Full Text Available This paper provides an analysis of the implications of climate change for forests and rangelands in southern Africa. The extent of the resources and their economic and social functions and drivers of change is outlined. The vulnerability...
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The challenge of integrated rangeland monitoring: synthesis address
African Journals Online (AJOL)
The utility of monitoring and its guiding principles will only work effectively where good environmental governance is practiced by users and producers affecting rangeland ecosystems. Keywords: adaptive management, complex, environmental governance, human impacts, multi-scale, socio-ecological. African Journal of ...
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Effect of management on rangeland phytomass, cover and condition ...
African Journals Online (AJOL)
similarity of management effects on rangeland condition and forage provision across major dryland biomes. Taking a macro-ecological perspective, we analysed if management effects differed between South Africa's central grassland and ...
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Transcending Landscapes: Working Across Scales and Levels in Pastoralist Rangeland Governance.
Robinson, Lance W; Ontiri, Enoch; Alemu, Tsegaye; Moiko, Stephen S
2017-08-01
Landscape approaches can be subjected to mistakenly targeting a single "best" level of governance, and paying too little attention to the role that cross-scale and cross-level interactions play in governance. In rangeland settings, resources, patterns of use of those resources, and the institutions for managing the resources exist at multiple levels and scales. While the scholarship on commons offers some guidance on how to conceptualize governance in rangeland landscapes, some elements of commons scholarship-notably the "design principles" for effective governance of commons-do not seem to apply neatly to governance in pastoralist rangeland settings. This paper examines three cases where attempts have been made to foster effective landscape governance in such settings to consider how the materiality of commons influences the nature of cross-scale and cross-level interactions, and how these interactions affect governance. In all three cases, although external actors seemed to work appropriately and effectively at community and landscape levels, landscape governance mechanisms have been facing great challenges arising from relationships beyond the landscape, both vertically to higher levels of decision-making and horizontally to communities normally residing in other landscapes. The cases demonstrate that fostering effective landscape-level governance cannot be accomplished only through action at the landscape level; it is a task that must be pursued at multiple levels and in relation to the connections across scales and levels. The paper suggests elements of a conceptual framework for understanding cross-level and cross-scale elements of landscape governance, and offers suggestions for governance design in pastoralist rangeland settings.
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Transcending Landscapes: Working Across Scales and Levels in Pastoralist Rangeland Governance
Robinson, Lance W.; Ontiri, Enoch; Alemu, Tsegaye; Moiko, Stephen S.
2017-08-01
Landscape approaches can be subjected to mistakenly targeting a single "best" level of governance, and paying too little attention to the role that cross-scale and cross-level interactions play in governance. In rangeland settings, resources, patterns of use of those resources, and the institutions for managing the resources exist at multiple levels and scales. While the scholarship on commons offers some guidance on how to conceptualize governance in rangeland landscapes, some elements of commons scholarship—notably the "design principles" for effective governance of commons—do not seem to apply neatly to governance in pastoralist rangeland settings. This paper examines three cases where attempts have been made to foster effective landscape governance in such settings to consider how the materiality of commons influences the nature of cross-scale and cross-level interactions, and how these interactions affect governance. In all three cases, although external actors seemed to work appropriately and effectively at community and landscape levels, landscape governance mechanisms have been facing great challenges arising from relationships beyond the landscape, both vertically to higher levels of decision-making and horizontally to communities normally residing in other landscapes. The cases demonstrate that fostering effective landscape-level governance cannot be accomplished only through action at the landscape level; it is a task that must be pursued at multiple levels and in relation to the connections across scales and levels. The paper suggests elements of a conceptual framework for understanding cross-level and cross-scale elements of landscape governance, and offers suggestions for governance design in pastoralist rangeland settings.
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Runoff and soil erosion from two rangeland sites
Historically over 50 years of rainfall/runoff research using rainfall simulators has been conducted at various rangeland sites in the West, however these sites rarely have consecutive yearly measurements. This limits the understanding of dynamic annual conditions and the interactions of grazing, pla...
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Sun, T; Liu, Z Y; Qin, L P; Long, R J
2015-01-01
In order to describe grasshopper (Orthoptera: Acrididae) species composition, diversity, abundance, and density of four rangelands types, we compared the grasshopper community composition and dynamics in the rangeland of the northern slopes of the Qilian Mountains. In total, 55 grasshopper species were collected from 2007 to 2009, representing three families and six subfamilies. The subfamily Oedipodinae was dominant, followed by Gomphocerinae and Catantopinae. Species abundance varied among rangeland types (RTs). The greatest abundance of grasshoppers was found in mountain rangeland, while the lowest abundance of grasshoppers was caught in alpine shrublands. Three species (Chorthippus cf. brunneus (Thunberg) (Acrididae), Chorthippus Dubius (Zubovski), and Gomphocerus licenti (Chang) were broadly distributed in the four RTs and constituted 7.5% of all grasshoppers collected. Ch. dubius was very abundant in desert rangeland and alpine shrubland. Bryodema dolichoptera Yin et Feng Eremippus qilianshanensis Lian and Zheng, and Filchnerella qilianshanensis Xi and Zheng (Pamphagidae) were endemic to the region of the Qilian Mountains. Species similarity between RTs ranged from 17.8 to 51.6 based on the Renkonen index. Similarly, the Sörensen index indicated a wide separation in species composition among RTs. The abundance of the eight most common species showed obvious differences among RTs and years. On average, mountain rangeland had the highest density values in 2007 and 2008, and alpine shrubland supported the smallest density. The densities in desert and mountain rangeland in 2007 were significantly higher than in 2008, while alpine rangeland and shrublands did not present obvious differences among years. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.
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Directory of Open Access Journals (Sweden)
M. Jankju
2016-04-01
Full Text Available Studying the autecology of range plants provides the basic information on their ecological requirements, cultivation methods and the interactions with the prevailing environment. Such information is necessary for a proper range management. Some ecological characteristics of Astragalus arpilobus Kar. & Kir., were studied in the winter rangelands of Northern Khorasan province. It was naturally growing in Jargalan, Bojnourd, where the altitudinal range varied 500-600 a.s.l, slope 20-100%, and the average annual rainfall 236.85 mm. Soil properties were: loamy texture, average organic matter, low fertility, pH 7.32 and EC 2.30 ds.m-1. A. aripilobus started vegetative growth at the early March, flowering during early May, seed production during June, and terminated its yearly growth at early July. The highest nutritive values and forage quality were at the beginning of growth, which was gradually decreased towards the end of growth season. Crude protein (CP, and ash were decreased whereas acid detergent fiber (ADF, natural detergent fiber (NDF, and dry matter (DM increased by the growing season. Seeds were easily established within pots; however, seed germination rate was low (24%, which by sand paper scarification was increased up to 51%. In conclusion, feasibility of seedling establishment, high nutritive value, and concurrence of plant phenology with the time of maximum need to fodder, by livestocks, propose A. arpilobus as a promising forage plant species for restoration of the winter rangelands in Northern Khorasan province.
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Williams, C. J.; Pierson, F. B.; Robichaud, P. R.; Boll, J.; Al-Hamdan, O. Z.
2011-12-01
The increased role of wildland fire across the rangeland-xeric forest continuum in the western United States (US) presents landscape-scale consequences relative runoff and erosion. Concomitant climate conditions and altered plant community transitions in recent decades along grassland-shrubland-woodland-xeric forest transitions have promoted frequent and large wildland fires, and the continuance of the trend appears likely if current or warming climate conditions prevail. Much of the Great Basin and Intermountain West in the US now exists in a state in which rangeland and woodland wildfires stimulated by invasive cheatgrass and dense, horizontal and vertical fuel layers have a greater likelihood of progressing upslope into xeric forests. Drier moisture conditions and warmer seasonal air temperatures, along with dense fuel loads, have lengthened fire seasons and facilitated an increase in the frequency, severity and area burned in mid-elevation western US forests. These changes potentially increase the overall hydrologic vulnerability across the rangeland-xeric forest continuum by spatially and temporally increasing soil surface exposure to runoff and erosion processes. Plot-to-hillslope scale studies demonstrate burning may increase event runoff and/or erosion by factors of 2-40 over small-plots scales and more than 100-fold over large-plot to hillslope scales. Anecdotal reports of large-scale flooding and debris-flow events from rangelands and xeric forests following burning document the potential risk to resources (soil loss, water quality, degraded aquatic habitat, etc.), property and infrastructure, and human life. Such risks are particularly concerning for urban centers near the urban-wildland interface. We do not yet know the long-term ramifications of frequent soil loss associated with commonly occurring runoff events on repeatedly burned sites. However, plot to landscape-scale post-fire erosion rate estimates suggest potential losses of biologically
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Rangeland Ecosystem Services: Nature's Supply and Humans' Demand
Ecosystem services are the benefits that society receives from nature and they include the regulation of climate, the pollination of crops, the provisioning of intellectual inspiration and recreational environment, as well as many essential goods such as food, fiber, and wood. Rangeland ecosystem se...
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Livestock systems and rangeland degradation in the new World Atlas of Desertification
Zucca, Claudio; Reynolds, James F.; Cherlet, Michael
2015-04-01
Livestock systems and rangeland degradation in the new World Atlas of Desertification Land degradation and desertification (LDD), which are widespread in global rangelands, are complex processes. They are caused by multiple (but limited) number of biophysical and socioeconomic drivers that lead to an unbalance in the capacity of the land to sustainably produce ecosystem services and economic value. Converging evidence indicates that the key biophysical and socioeconomic drivers include agricultural or pastoral land use and management practices, population growth, societal demands (e.g., urbanization), and climate change (e.g., increasing aridity and drought). The new World Atlas of Desertification (WAD) describes these global issues, documents their spatial change, and highlights the importance of these drivers in relation to land degradation processes. The impacts of LDD on the atmosphere, on water and on biodiversity are also covered. The WAD spatially illustrates relevant types of livestock and rangeland management systems, related (over-under) use of resources, various management activities, and some of the common features and transitions that contribute to LDD. For example, livestock grazing in marginal areas is increasing due to competition with agricultural encroachment and, hence, vulnerable lands are under threat. The integration of stratified global data layers facilitates identifying areas where stress on the land system can be linked to underlying causal issues. One of the objectives of the new WAD is to provide synthesis and tools for scientists and stakeholders to design sustainable solutions for efficient land use in global rangelands.
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A conceptual tool for improving rangeland management decision ...
African Journals Online (AJOL)
... the LLM concept should be seen as a continuous and evolving learning process that will be updated over the long term through decision support to include several other components essential to implement effective and sustainable rangeland management practices by local land users. Keywords: desertification; indicators ...
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Directory of Open Access Journals (Sweden)
John A. Ludwig
2005-12-01
Full Text Available Many rangelands around the globe are degraded because of mismatches between the goals and actions of managers operating at different spatial scales. In this paper, we focus on identifying, interpreting, and correcting cross-scale mismatches in rangeland management by building on an existing four-step resilience analysis procedure. Resilience analysis is an evaluation of the capacity of a system to persist in the face of disturbances. We provide three examples of cross-scale resilience analysis using a rangeland system located in northern Australia. The system was summarized in a diagram showing key interactions between three attributes (water quality, regional biodiversity, and beef quality, which can be used to indicate the degree of resilience of the system, and other components that affect these attributes at different scales. The strengths of cross-scale interactions were rated as strong or weak, and the likely causes of mismatches in strength were interpreted. Possible actions to correct cross-scale mismatches were suggested and evaluated. We found this four-step, cross-scale resilience analysis procedure very helpful because it reduced a complex problem down to manageable parts without losing sight of the larger-scale whole. To build rangeland resilience, many such cross-scale mismatches in management will need to be corrected, especially as the global use of rangelands increases over the coming decades.
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Runoff and erosion estimates are needed for rangeland management decisions and evaluation of ecosystem services derived from rangeland conservation practices. The information on the effect of scale on the runoff and erosion, and on the choice of runoff and erosion predictors, remains scarce. The obj...
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Yield Response of Mediterranean Rangelands under a Changing Climate
Daliakopoulos, Ioannis N.; Panagea, Ioanna S.; Tsanis, Ioannis K.; Grillakis, Manolis G.; Koutroulis, Aristeidis G.; Hessel, Rudi; Mayor, Angeles G.; Ritsema, Coen J.
2017-01-01
Understanding the Mediterranean rangelands degradation trends is a key element of mitigating their vulnerability and enhancing their resilience. Climate change and its inherent effects on mean temperature and the precipitation variability can regulate the magnitude, frequency and duration of
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Presidential address - 1999 Towards a national rangeland policy ...
African Journals Online (AJOL)
There are some problems with the publication of the journal, but Council hopes to have our ... The first is that all agencies funded through DACST will be reviewed ... to improve our understanding of management issues in communal rangeland. ... All current programmes to rehabilitate degraded land contain budgets for the ...
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Monitoring Forage Production of California Rangeland Using Remote Sensing Observations
Liu, H.; Jin, Y.; Dahlgren, R. A.; O'Geen, A. T.; Roche, L. M.; Smith, A. M.; Flavell, D.
2016-12-01
Pastures and rangeland cover more than 10 million hectares in California's coastal and inland foothill regions, providing feeds to livestock and important ecosystem services. Forage production in California has a large year-to-year variation due to large inter-annual and seasonal variabilities in precipitation and temperature. It also varies spatially due to the variability in climate and soils. Our goal is to develop a robust and cost-effective tool to map the near-real-time and historical forage productivity in California using remote sensing observations from Landsat and MODIS satellites. We used a Monteith's eco-physiological plant growth theory: the aboveground net primary production (ANPP) is determined by (i) the absorbed photosynthetically active radiation (APAR) and the (ii) light use efficiency (LUE): ANPP = APAR * LUEmax * f(T) * f(SM), where LUEmax is the maximum LUE, and f(T) and f(SM) are the temperature and soil moisture constrains on LUE. APAR was estimated with Landsat and MODIS vegetation index (VI), and LUE was calibrated with a statewide point dataset of peak forage production measurements at 75 annual rangeland sites. A non-linear optimization was performed to derive maximum LUE and the parameters for temperature and soil moisture regulation on LUE by minimizing the differences between the estimated and measured ANPP. Our results showed the satellite-derived annual forage production estimates correlated well withcontemporaneous in-situ forage measurements and captured both the spatial and temporal productivity patterns of forage productivity well. This remote sensing algorithm can be further improved as new field measurements become available. This tool will have a great importance in maintaining a sustainable range industry by providing key knowledge for ranchers and the stakeholders to make managerial decisions.
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Sasaki, Takehiro; Okubo, Satoru; Okayasu, Tomoo; Jamsran, Undarmaa; Ohkuro, Toshiya; Takeuchi, Kazuhiko
2009-03-01
The current growing body of evidence for diversity-disturbance relationships suggests that the peaked pattern predicted by the intermediate disturbance hypothesis (IDH) may not be the rule. Even if ecologists could quantify the diversity-disturbance relationship consistent with the IDH, the applicability of the IDH to land management has rarely been addressed. We examined two hypotheses related to the generality and management applicability of the IDH to Mongolian rangeland ecosystems: that the diversity-disturbance relationship varies as a function of landscape condition and that some intermediate scales of grazing can play an important role in terms of sustainable rangeland management through a grazing gradient approach. We quantified the landscape condition of each ecological site using an ordination technique and determined two types of landscape conditions: relatively benign and harsh environmental conditions. At the ecological sites characterized by relatively benign environmental conditions, diversity-disturbance relationships were generally consistent with the IDH, and maximum diversity was observed at some intermediate distance from the source of the grazing gradient. In contrast, the IDH was not supported at most (but not all) sites characterized by relatively harsh environmental conditions. The intermediate levels of grazing were generally located below the ecological threshold representing the points or zones at which disturbance should be limited to prevent drastic changes in ecological conditions, suggesting that there is little "conundrum" with regard to intermediate disturbance in the studied systems in terms of land management. We suggest that the landscape condition is one of the primary factors that cause inconsistencies in diversity-disturbance relationships. The ecological threshold can extend its utility in rangeland management because it also has the compatibility with the maintenance of species diversity. This study thus suggests that some
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Plant establishment and soil microenvironments in Utah juniper masticated woodlands
Kert R. Young
2012-01-01
Juniper (Juniperus spp.) encroachment into sagebrush (Artemisia spp.) and bunchgrass communities has reduced understory plant cover and allowed juniper trees to dominate millions of hectares of semiarid rangelands. Trees are mechanically masticated or shredded to decrease wildfire potential and increase desirable understory plant cover. When trees are masticated after...
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Paul L. Patterson; James Alegria; Leonard Jolley; Doug Powell; J. Jeffery Goebel; Gregg M. Riegel; Kurt H. Riitters; Craig. Ducey
2014-01-01
Rangelands are lands dominated by grasses, forbs, and shrubs and are managed as a natural ecosystem. Although these lands comprise approximately 40 percent of the landmass of the continental United States, there is no coordinated effort designed to inventory, monitor, or assess rangeland conditions at the national scale. A pilot project in central Oregon with the U.S....
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Rangeland restoration for Hirola, the world's most endangered antelope
Rangeland restoration can improve habitat for threatened species such as the hirola antelope (Beatragus hunteri) that inhabit savannas of eastern Kenya. However, restoration success likely varies across soil types and target restoration species, as well as according to restoration approach. We teste...
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State and transition models (STMs) are used for communicating about ecosystem change in rangelands and other ecosystems, especially the implications for management. The fundamental premise that rangelands can exhibit multiple states is now widely accepted. The current application of STMs for managem...
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Rangeland degradation in two watersheds of Lebanon
International Nuclear Information System (INIS)
Darwish, T; Faour, G.
2008-01-01
A complex and rugged nature characterizes the Lebanese mountains.The climatic pattern prevailing in the country, deforestation and man made erosion caused increased rangeland degradation. The purpose of this study was to monitor two contrasting watersheds, representing the Lebanese agro-ecological zones, to analyze the vegetation dynamics and trace the state of rangeland degradation. The Kfarselouane (205 km2) and Aarsal (316.7 km2) watersheds are located in the Lebanon and Anti-Lebanon mountain chain and characterized by sub humid and semi-arid climate respectively.Using multitemporal spot vegetation images between 1999 and 2005 to analyze the normalized differential vegetation index (NDVI) revealed some improvement of the vegetation cover over recent years in Kfaselouane with a steady state in Aarsal. The NDVI trend curve inclines in spring and declines in summer and fall. Judging by the time scale amplitude change and highest magnitude between the peak and lower NDVI level in Aarsal, an increased vulnerability to drought is observed in the dry Lebanese areas. Comparing land cover/use in Aarsal area between 1962 and 2000 using aerial photos and large resolution Indian satellite images (IRS) showed wood fragmentation and slight increase of the degenerated forest cover from 1108 ha to 1168 ha. Landuse change was accompanied by a simultaneous increase of cultivated lands (mostly fruit trees) from 932 ha to 4878 ha with absence of soil conservation and water harvesting practices. On the contrary, grasslands decreased from 29581 ha to 25000 ha. In Kfarselouane, the area of grassland was invaded by forestland where rangeland decreased from 8073 ha to 3568 ha and woodland increased from 5766 ha to 11800 ha. Forest expansion occurred even at the account of unproductive land which decreased from 2668 ha to 248 ha, while cultivated lands did not reveal any substantial change. Based on animals' seasonal feeding pattern, a mismatch between land carrying capacity and grazing
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Ecology and Conservation of Acacia senegal in the Rangelands ...
African Journals Online (AJOL)
Ecology and Conservation of Acacia senegal in the Rangelands ofLuwero and Nakasongola Districts. Jacob Godfrey Agea, Joseph Obua, Sara Namirembe, Mukadasi Buyinza, Daniel Waiswa. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...
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Advances in modeling soil erosion after disturbance on rangelands
Research has been undertaken to develop process based models that predict soil erosion rate after disturbance on rangelands. In these models soil detachment is predicted as a combination of multiple erosion processes, rain splash and thin sheet flow (splash and sheet) detachment and concentrated flo...
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Ranch business planning and resource monitoring for rangeland sustainability
Kristie A. Maczko; John A. Tanaka; Michael Smith; Cindy Garretson-Weibel; Stanley F. Hamilton; John E. Mitchell; Gene Fults; Charles Stanley; Dick Loper; Larry D. Bryant; J. K. (Rooter) Brite
2012-01-01
Aligning a rancher's business plan goals with the capability of the ranch's rangeland resources improves the viability and sustainability of family ranches. Strategically monitoring the condition of soil, water, vegetation, wildlife, livestock production, and economics helps inform business plan goals. Business planning and resource monitoring help keep...
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Phenomapping of rangelands in South Africa using time series of RapidEye data
Parplies, André; Dubovyk, Olena; Tewes, Andreas; Mund, Jan-Peter; Schellberg, Jürgen
2016-12-01
Phenomapping is an approach which allows the derivation of spatial patterns of vegetation phenology and rangeland productivity based on time series of vegetation indices. In our study, we propose a new spatial mapping approach which combines phenometrics derived from high resolution (HR) satellite time series with spatial logistic regression modeling to discriminate land management systems in rangelands. From the RapidEye time series for selected rangelands in South Africa, we calculated bi-weekly noise reduced Normalized Difference Vegetation Index (NDVI) images. For the growing season of 2011⿿2012, we further derived principal phenology metrics such as start, end and length of growing season and related phenological variables such as amplitude, left derivative and small integral of the NDVI curve. We then mapped these phenometrics across two different tenure systems, communal and commercial, at the very detailed spatial resolution of 5 m. The result of a binary logistic regression (BLR) has shown that the amplitude and the left derivative of the NDVI curve were statistically significant. These indicators are useful to discriminate commercial from communal rangeland systems. We conclude that phenomapping combined with spatial modeling is a powerful tool that allows efficient aggregation of phenology and productivity metrics for spatially explicit analysis of the relationships of crop phenology with site conditions and management. This approach has particular potential for disaggregated and patchy environments such as in farming systems in semi-arid South Africa, where phenology varies considerably among and within years. Further, we see a strong perspective for phenomapping to support spatially explicit modelling of vegetation.
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Ecology and utilization of desert shrub rangelands in Iraq
Thalen, Derk Catharinus Peter
1979-01-01
When grazing is the accepted land use, vegetation is the key resource. The present study deals with the desert shrub rangelands of lraq, which contain the major characteristics of such an area, having been under grazing for many centuries. Emphasis is given to the ecology and utilization of the
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The value of milk in rangelands in Mandera County, Kenya
Ngugi, Keziah; Ertsen, Maurits
2015-04-01
Lack of water over expansive regions in Greater Horn of Africa created the rangelands and rangelands created pastoralism. Pastoralism involve keeping of large livestock herds and movement in search of resources, mainly water, pasture, medicine and wild foods. Several studies have been done in the last century and findings pointed at pastoralism being primitive and unsustainable. It has been predicted it would die in the last century but in the rangelands, pastoralism lives on and it is resilient. This study is based in Mandera, a pastoralism county in Kenya that neighbors Ethiopia to the North and Somalia to the East. The study sought to investigate contribution of milk to pastoralism resilience. Interviews were conducted in the field among the pastoralists, women groups, transporters, traders, government officials and consumers of milk. These information was corroborated with actual field investigations in the expansive rangelands of Mandera County. Pastoralists rarely slaughter or sell their livestock even when the animals waste away during droughts. This is because they have been through such cycles before and observed livestock make tremendous recovery when the right conditions were restored. Rangelands lack infrastructure, there are no roads, schools, telephone or hospitals. Pastoralists diet is comprised of rice, wheat and milk. It was established milk was the main source of income among pastoralists in Mandera County. From milk, the pastoralists make income that is used to purchase the other foodstuffs. Milk is available on daily basis in large quantities owing to the large number of livestock. Unfortunately, every pastoralist household produce copious amounts of milk, thus no local demand and transport infrastructure is nonexistent, making sale of milk a near impossible task. The findings showed the pastoralists have established unique routes through which milk reach the markets in urban centers where demand is high. Urbanization sustain pastoralism. These
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Matthew Clark Reeves; John E. Mitchell
2012-01-01
The Renewable Resources Planning Act of 1974 requires the USDA Forest Service to conduct assessments of resource conditions. This report fulfills that need and focuses on quantifying extent, productivity, and health of U.S. rangelands. Since 1982, the area of U.S. rangelands has decreased at an average rate of 350,000 acres per year owed mostly to conversion to...
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Parameterization of erodibility in the Rangeland Hydrology and Erosion Model
The magnitude of erosion from a hillslope is governed by the availability of sediment and connectivity of runoff and erosion processes. For undisturbed rangelands, sediment is primarily detached and transported by rainsplash and sheetflow (splash-sheet) processes in isolated bare batches, but sedime...
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Use of biosolids to enhance rangeland forage quality.
McFarland, Michael J; Vasquez, Issaak Romero; Vutran, MaiAnh; Schmitz, Mark; Brobst, Robert B
2010-05-01
Biosolids land application was demonstrated to be a potentially cost-effective means for restoring forage productivity and enhancing soil-moisture-holding capacity on disturbed rangelands. By land-applying aerobically digested, anaerobically digested, composted, and lime-stabilized biosolids on rangeland test plots at rates of up to 20 times (20X) the estimated nitrogen-based agronomic rate, forage yields were found to increase from 132.8 kg/ha (118.2 lb/ac) (control plots) to 1182.3 kg/ha (1052.8 lb/ac). Despite the environmental benefits associated with increased forage yield (e.g., reduced soil erosion, improved drainage, and enhanced terrestrial carbon sequestration), the type of forage generated both before and after biosolids land application was found to be dominated by invasive weeds, all of which were characterized as having fair to poor nutritional value. Opportunistic and shallow rooting invasive weeds not only have marginal nutritional value, they also limit the establishment of native perennial grasses and thus biodiversity. Many of the identified invasive species (e.g., Cheatgrass) mature early, a characteristic that significantly increases the fuel loads that support the increased frequency and extent of western wildfires.
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Lohani, S.; Heilman, P.; deSteiguer, J. E.; Guertin, D. P.; Wissler, C.; McClaran, M. P.
2014-12-01
Quantifying ecosystem services is a crucial topic for land management decision making. However, market prices are usually not able to capture all the ecosystem services and disservices. Ecosystem services from rangelands, that cover 70% of the world's land area, are even less well-understood since knowledge of rangelands is limited. This study generated a management framework for rangelands that uses remote sensing to generate state and transition models (STMs) for a large area and a linear programming (LP) model that uses ecosystem services to evaluate natural and/or management induced transitions as described in the STM. The LP optimization model determines the best management plan for a plot of semi-arid land in the Empire Ranch in southeastern Arizona. The model allocated land among management activities (do nothing, grazing, fire, and brush removal) to optimize net benefits and determined the impact of monetizing environmental services and disservices on net benefits, acreage allocation and production output. The ecosystem services under study were forage production (AUM/ac/yr), sediment (lbs/ac/yr), water runoff (inches/yr), soil loss (lbs/ac/yr) and recreation (thousands of number of visitors/ac/yr). The optimization model was run for three different scenarios - private rancher, public rancher including environmental services and excluding disservices, and public rancher including both services and disservices. The net benefit was the highest for the public rancher excluding the disservices. A result from the study is a constrained optimization model that incorporates ecosystem services to analyze investments on conservation and management activities. Rangeland managers can use this model to understand and explain, not prescribe, the tradeoffs of management investments.
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Agroforestry potential of Acacia senegal in the rangelands of luwero ...
African Journals Online (AJOL)
Agroforestry potential of Acacia senegal in the rangelands of luwero and Nakasongola districts. Jacob Godfrey Agea, Joseph Obua, Sara Namirembe, Mukadasi Buyinza, Daniel Waiswa. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.
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Session B1 Management for sustainable use — Rangeland auditing ...
African Journals Online (AJOL)
Social, economic and cultural needs, values and expectations will be examined together with the biophysical technologies and approaches which underlie auditing in rangeland science. Adaptive frameworks which enhance sustainable strategic responses, and the state of art in scale dilemmas will be addressed. A hybrid ...
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Multi-scale wind erosion monitoring and assessment for US rangelands
Wind erosion is a major resource concern for rangeland managers. Although wind erosion is a naturally occurring process in many drylands, land use activities, and land management in particular, can accelerate wind-driven soil loss – impacting ecosystem dynamics and agricultural production, air quali...
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Session A6 Rangelands as dynamic systems — Fragmentation of ...
African Journals Online (AJOL)
Biological complexity in rangelands arises from spatially-linked ecological states and processes. Herbivores, humans and other agents integrate distinct spatial units into complex systems by moving among and exploiting these units. Spatial heterogeneity plays a central role in the structure and function of grazed ...
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A review of climate change effects on terrestrial rangeland birds
D. M. Finch; K. E. Bagne; M. M. Friggens; D. M. Smith; K. M. Brodhead
2011-01-01
We evaluated existing literature on predicted and known climate change effects on terrestrial rangeland birds. We asked the following questions: 1) How does climate change affect birds? 2) How will birds respond to climate change? 3) Are species already responding? 4) How will habitats be impacted?
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Determining termite diversity in arid Namibian rangelands – a ...
African Journals Online (AJOL)
Three methods of sampling termite diversity in arid rangelands were tested in Namibia during the wet (March) and dry (October) seasons of 1998. Six sites were chosen: one pair on each of three farms representing a gradient of land use intensity. At each site, two adjacent plots of 1 ha each were sampled: one plot by a ...
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Session B1 Management for sustainable use — Rangeland auditing ...
African Journals Online (AJOL)
We need to monitor the capacity of healthy rangeland to support a broad suite of ecosystem services for a wide range of stakeholders — in a fair, objective and representative way. ... A hybrid session structure will be utilised: distilling wisdom from relevant posters; formal presentations; and stimulating structured debate.
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Chu, Jianmin; Yang, Hongxiao; Lu, Qi; Zhang, Xiaoyan
2015-06-03
Some endemic shrubs in arid and semiarid ecosystems are in danger of extinction, and yet they can play useful roles in maintaining or restoring these ecosystems, thus practical efforts are needed to conserve them. The shrubs Amygdalus pedunculata Pall., Amygdalus mongolica (Maxim.) Ricker and Ammopiptanthus mongolicus (Maxim. ex Kom.) Cheng f. are endemic species in arid and semiarid regions of northern China, where rangeland desertification is pronounced due to chronic overgrazing. In this study, we tested the hypothesis that these endemic shrubs have developed adaptations to arid and semiarid environments and could play critical roles as nurse species to initiate the process of rangeland recovery. Based on careful vegetation surveys, we analysed the niches of these species in relation to precipitation, temperature and habitats. All sampling plots were categorized by these endemics and sorted by the non-metric multidimensional scaling method. Species ratios of each life form and species co-occurrence rates with the endemics were also evaluated. Annual average temperature and annual precipitation were found to be the key factors determining vegetation diversity and distributions. Amygdalus pedunculata prefers low hills and sandy land in temperate semiarid regions. Amygdalus mongolica prefers gravel deserts of temperate semiarid regions. Ammopiptanthus mongolicus prefers sandy land of temperate arid regions. Communities of A. pedunculata have the highest diversity and the largest ratios of long-lived grass species, whereas those of A. mongolicus have the lowest diversity but the largest ratios of shrub species. Communities of A. mongolica are a transition between the first two community types. These findings demonstrate that our focal endemic shrubs have evolved adaptations to arid and semiarid conditions, thus they can be nurse plants to stabilize sand ground for vegetation restoration. We suggest that land managers begin using these shrub species to restore
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Soil properties are thought to affect rangeland ecosystem functioning (e.g. primary productivity, hydrology), and thus soil variables that are consistently correlated with key ecosystem functions may be general indicators of rangeland health. We summarize results from several studies in mixed-grass...
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Session A5 Rangelands as dynamic systems Role of wildlife in ...
African Journals Online (AJOL)
Rangelands in southern Africa are increasingly being used for conservation, ecotourism, game farming and hunting. This impacts people's livelihoods and the state of natural resources. Complimentarity and competition between wildlife and domestic livestock can be explored. Theme: This session focuses on ecosystem ...
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Temperament affects rangeland use patterns and reproductive performance of beef cows
• The American beef industry is paying more attention to cattle temperament, but studies examining relationships between temperaments and grazing behavior or animal performance on rangelands are limited. • We studied range beef cow temperaments using the behavioral syndromes framework. Cows classifi...
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The importance of education in managing invasive plant species
Invasive plant species can establish in diverse environments and with the increase in human mobility, they are no longer restricted to isolated pockets in remote parts of the world. Cheat grass (Bromus tectorum L.) in rangelands, purple loosestrife (Lythrum salicaria L.) in wet lands and Canada this...
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Vulnerability of amphibians to climate change: implications for rangeland management
Karen E. Bagne; Deborah M. Finch; Megan M. Friggens
2011-01-01
Many amphibian populations have declined drastically in recent years due to a large number of factors including the emerging threat of climate change (Wake 2007). Rangelands provide important habitat for amphibians. In addition to natural wetlands, stock tanks and other artificial water catchments provide habitat for many amphibian species (Euliss et al. 2004).
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Analysis reveals potential rangeland impacts if Williamson Act eliminated
Directory of Open Access Journals (Sweden)
William C. Wetzel
2012-10-01
Full Text Available California budget cuts have resulted in dramatic reductions in state funding for the Williamson Act, a land protection program that reduces property taxes for the owners of 15 million acres of California farms and rangeland. With state reimbursements to counties eliminated, the decision to continue Williamson Act contracts lies with individual counties. We investigated the consequences of eliminating the Williamson Act, using a geospatial analysis and a mail questionnaire asking ranchers for plans under a hypothetical elimination scenario. The geospatial analysis revealed that 72% of rangeland parcels enrolled in Williamson Act contracts contained habitat important for statewide conservation goals. Presented with the elimination scenario, survey respondents reported an intention to sell 20% of their total 496,889 acres. The tendency of survey participants to respond that they would sell land was highest among full-time ranchers with low household incomes and without off-ranch employment. A majority (76% of the ranchers who reported that they would sell land predicted that the buyers would develop it for nonagricultural uses, suggesting substantial changes to California's landscape in a future without the Williamson Act.
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Fodder Biomass Monitoring in Sahelian Rangelands Using Phenological Metrics from FAPAR Time Series
DEFF Research Database (Denmark)
Diouf, Abdoul Aziz; Brandt, Martin Stefan; Verger, Aleixandre
2015-01-01
Timely monitoring of plant biomass is critical for the management of forage resources in Sahelian rangelands. The estimation of annual biomass production in the Sahel is based on a simple relationship between satellite annual Normalized Difference Vegetation Index (NDVI) and in situ biomass data....... This study proposes a new methodology using multi-linear models between phenological metrics from the SPOT-VEGETATION time series of Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) and in situ biomass. A model with three variables—large seasonal integral (LINTG), length of growing season......, and end of season decreasing rate—performed best (MAE = 605 kg·DM/ha; R2 = 0.68) across Sahelian ecosystems in Senegal (data for the period 1999–2013). A model with annual maximum (PEAK) and start date of season showed similar performances (MAE = 625 kg·DM/ha; R2 = 0.64), allowing a timely estimation...
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2010-04-01
... § 166.307 Will the grazing capacity be increased if I graze adjacent trust or non-trust rangelands not... trust or non-trust rangeland in common with the permitted land. Grazing capacity will be established... 25 Indians 1 2010-04-01 2010-04-01 false Will the grazing capacity be increased if I graze...
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Reality of rangeland degradation mapping with remote sensing: the South African experience
CSIR Research Space (South Africa)
Wessels, Konrad J
2008-09-01
Full Text Available Globally there is an urgent need for standardized, quantitative measures rangeland degradation. Over the past 10 years in South Africa (SA), significant research efforts have been directed at this challenge, using diverse methods and data...
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Salinity mobilization and transport from rangelands: assessment, recommendations, and knowledge gaps
The purpose of the salinity project is to improve the understanding of sources and transport mechanisms in rangeland catchments that deliver dissolved solids (salts) to streams within the Upper Colorado River Basin (UCRB) through a review of relevant literature on what is known about the impact of r...
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Using faecal DNA to determine consumption by kangaroos of plants considered palatable to sheep.
Ho, K W; Krebs, G L; McCafferty, P; van Wyngaarden, S P; Addison, J
2010-02-01
Disagreement exists within the scientific community with regards to the level of competition for feed between sheep and kangaroos in the Australian rangelands. The greatest challenge to solving this debate is finding effective means of determining the composition of the diets of these potential grazing competitors. An option is to adopt a non-invasive approach that combines faecal collection and molecular techniques that focus on faecal DNA as the primary source of dietary information. As proof-of-concept, we show that a DNA reference data bank on plant species can be established. This DNA reference data bank was then used as a library to identify plant species in kangaroo faeces collected in the southern rangelands of Western Australia. To enhance the method development and to begin the investigation of competitive grazing between sheep and kangaroos, 16 plant species known to be palatable to sheep were initially targeted for collection. To ensure that only plant sequences were studied, PCR amplification was performed using a universal primer pair previously shown to be specific to the chloroplast transfer RNA leucine (trnL) UAA gene intron. Overall, genus-specific, single and differently sized amplicons were reliably and reproducibly generated; enabling the differentiation of reference plants by PCR product length heterogeneity. However, there were a few plants that could not be clearly differentiated on the basis of size alone. This prompted the adoption of a post-PCR step that enabled further differentiation according to base sequence variation. Restriction endonucleases make sequence-specific cleavages on DNA to produce discrete and reproducible fragments having unique sizes and base compositions. Their availability, affordability and simplicity-of-use put restriction enzyme sequence (RES) profiling as a logical post-PCR step for confirming plant species identity. We demonstrate that PCR-RES profiling of plant and faecal matter is useful for the identification
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Determining RUSLE P-factors for stonebunds and trenches in rangeland and cropland, Northern Ethiopia
Taye, Gebeyehu; Poesen, Jean; Vanmaercke, Matthias; Van Wesemael, Bas; Tesfay, Samuel; Teka, Daniel; Nyssen, Jan; Deckers, Jozef; Haregeweyn, Nigussie
2017-04-01
The implementation of soil and water conservation (SWC) measures in the Ethiopian highlands is a top priority to reduce soil erosion rates and to enhance the sustainability of agroecosystem. Nonetheless, the effectiveness of many of these measures for different hillslope and land use conditions remains currently poorly understood. As a result, the overall effects of these measures at regional or catchment scale remain hard to quantify. This study addresses this knowledge gap by determining the cover-management (C) and support practice (P) factors of the Revised Universal Soil Loss Equation (RUSLE), for commonly used SWC measures in semi-arid environments (i.e. stone bunds, trenches and a combination of both). Calculations were based on soil loss data collected with runoff plots in Tigray, northern Ethiopia (i.e. 21 runoff plots of 600 to 1000 m2, monitored during 2010, 2011 and 2012). The runoff plots were installed in rangeland and cropland sites corresponding to a gentle (5%), medium (12%) and steep (16%) slope gradients. The C and P factors of the RUSLE were calculated following the recommended standard procedures. Results show that the C-factor for rangeland ranges from 0.31 to 0.98 and from 0.06 to 0.39 for cropland. For rangeland, this large variability is due to variations in vegetation cover caused by grazing. In cropland, C-factors vary with tillage practices and crop types. The calculated P-factors ranged from 0.32 to 0.74 for stone bunds, from 0.07 to 0.65 for trenches and from 0.03 to 0.22 for a combination of both stone bunds and trenches. This variability is partly due to variations in the density of the implemented measures in relation to land use (cropland vs rangeland) and slope angles. However, also annual variations in P factor values are highly significant. Especially trenches showed a very significant decline of effectiveness over time, which is attributable to their reduced static storage capacity as a result of sediment deposition (e.g. for
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Towards a remote sensing based indicator of rangeland ecosystem resistance and resilience
Understanding ecosystem resistance and resilience to disturbance and invasive species is critical to the sustainable management of rangeland systems. In this context, resistance refers to the inherent ability of an ecosystem to resist disturbance, while resilience refers to the capacity of an ecosys...
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Evaluating new SMAP soil moisture for drought monitoring in the rangelands of the US High Plains
Velpuri, Naga Manohar; Senay, Gabriel B.; Morisette, Jeffrey T.
2016-01-01
Level 3 soil moisture datasets from the recently launched Soil Moisture Active Passive (SMAP) satellite are evaluated for drought monitoring in rangelands.Validation of SMAP soil moisture (SSM) with in situ and modeled estimates showed high level of agreement.SSM showed the highest correlation with surface soil moisture (0-5 cm) and a strong correlation to depths up to 20 cm.SSM showed a reliable and expected response of capturing seasonal dynamics in relation to precipitation, land surface temperature, and evapotranspiration.Further evaluation using multi-year SMAP datasets is necessary to quantify the full benefits and limitations for drought monitoring in rangelands.
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Grazing management, resilience and the dynamics of a fire driven rangeland system
Anderies, J.M.; Janssen, M.A.; Walker, B.H.
2002-01-01
We developed a stylized mathematical model to explore the effects of physical, ecological, and economic factors on the resilience of a managed fire-driven rangeland system. Depending on grazing pressure, the model exhibits one of three distinct configurations: a fire-dominated, grazing-dominated, or
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Vulnerability of cattle production to climate change on U.S. rangelands
Matt C. Reeves; Karen E. Bagne
2016-01-01
We examined multiple climate change effects on cattle production for U.S. rangelands to estimate relative change and identify sources of vulnerability among seven regions. Climate change effects to 2100 were projected from published models for four elements: forage quantity, vegetation type trajectory, heat stress, and forage variability. Departure of projections from...
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Directory of Open Access Journals (Sweden)
Masahiro Tasumi
2014-09-01
Full Text Available Land degradation of alpine rangeland in Dachigam National Park, Northern India, was evaluated in this study using MODerate resolution Imaging Spectroradiometer (MODIS land products. The park has been used by a variety of livestock holders. With increasing numbers of livestock, the managers and users of the park are apprehensive about degradation of the grazing land. However, owing to weak infrastructure for scientific and statistical data collection and sociopolitical restrictions in the region, a lack of quality ground-based weather, vegetation, and livestock statistical data had prevented scientific assessment. Under these circumstances, the present study aimed to assess the rangeland environment and its degradation using MODIS vegetation, snow, and evapotranspiration products as primary input data for assessment. The result of the analysis indicated that soil water content and the timing of snowmelt play an important role in grass production in the area. Additionally, the possibility of land degradation in heavily-grazed rangeland was indicated via a multiple regression analysis at a decadal timescale, whereas weather conditions, such as rainfall and snow cover, primarily explained year-by-year differences in grass production. Although statistical uncertainties remain in the results derived in this study, the satellite-based data and the analyses will promote understanding of the rangeland environment and suggest the potential for unsustainable land management based on statistical probability. This study provides an important initial evaluation of alpine rangeland, for which ground-based information is limited.
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Soil Moisture Variability and its Effects on Herbage Production in Semi-arid Rangelands of Kenya
International Nuclear Information System (INIS)
Too, D.K.; Trlica, M.J.; Swift, D.M.; Musembi, D.K.
1999-01-01
Results obtained from recent studies focused on rangelands potential as influenced by human activity and climatic factors in the semi-arid and arid pastoral ecosystems of Northern Kenya indicated great temporal and spatial forage production variability. The objective of the studies was to document primary production in relation to water stress (drought), herbivory and direct human activities. Efforts also focused on finding possibilities of increasing productivity while conserving the finite resources for sustainable use. Laboratory, field and numerical methods were employed over several seasons and years. Forb and grass production was more variable than that of the browse (dwarf shrub) layer. Compared to forbs and dwarf shrubs, the grass layer contributed less to the total production in all seasons, indicating that the region had less potential for grazers compared to browsers. Spatial-temporal variation in rangeland carrying capacity reflected the great spatial heterogeneity in vegetation types and production. Similarly, seasonal differences were very evident, with highest estimates in the long rainy and the lowest during the dry and short rainy seasons, respectively. Factors limiting rangeland production potential were identified to be moisture deficiency, resource-use conflicts, an increasing and partially sedentarised nomadic population, overgrazing, tree felling, and land degradation (desert encroachment). Measures that can improve rangeland production potential and provide a better way of life for the inhabitants of the region include: (a) identification of land degradation (e.g. by means of bio-indicators and Geographical Information Systems, GIS); (b) technical interventions (i.e. soil and water conservation, restoration of degraded areas, fodder production); (c) social-economic interventions (i.e. resolution of resource-use conflicts, alleviation of poverty, infrastructure development improvement of livestock marketing channels etc.) and (d) continued
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Forage seeding in rangelands increases production and prevents weed invasion
Directory of Open Access Journals (Sweden)
Josh Davy
2017-07-01
Full Text Available Increasing forage productivity in the Sierra foothill rangelands would help sustain the livestock industry as land availability shrinks and lease rates rise, but hardly any studies have been done on forage selections. From 2009 to 2014, in one of the first long-term and replicated studies of seeding Northern California's Mediterranean annual rangeland, we compared the cover of 22 diverse forages to determine their establishment and survivability over time. Among the annual herbs, forage brassica (Brassica napus L. and chicory (Cichorium intybus L. proved viable options. Among the annual grasses, soft brome (Bromus hordeaceus and annual ryegrass (Lolium multiflorum performed well. However, these species will likely require frequent reseeding to maintain dominance. Long-term goals of sustained dominant cover (> 3 years are best achieved with perennial grasses. Perennial grasses that persisted with greater than 50% cover were Berber orchardgrass (Dactylis glomerata, Flecha tall fescue (Lolium arundinaceum and several varieties of hardinggrass (Phalaris aquatica L., Perla koleagrass, Holdfast, Advanced AT. In 2014, these successful perennials produced over three times more dry matter (pounds per acre than the unseeded control and also suppressed annual grasses and yellow starthistle (Centaurea solstitialis L. cover.
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Stakeholder Theory and Rangeland Management: The Importance of Ranch Income Dependence
Elias, S.; Roche, L. M.; Elias, E.
2016-12-01
The California drought beginning in 2012 has been driven by reduced precipitation and record high temperatures. Hydrologic drought in the Southwest United States is projected to become the new climatology of the region. While ranchers are considered naturally adaptive, often adeptly altering management based upon conditions, the projected increased aridity may challenge rangeland management. Certain rancher characteristics are likely to impact how well ranchers adapt. Based on Stakeholder Theory (ST), we hypothesize that the extent to which ranchers are dependent on their ranches as a source of income would serve as a predictor of several key variables related to ranching adaptation and success. Data were obtained from 507 ranchers throughout the State of California via the Rangeland Decision-Making Survey implemented by University of California, Davis in 2010, just prior to the unprecedented California drought. Consistent with the ST urgency facet, results of linear regression analyses indicate the more dependent ranchers are on their ranches for their income, the more aware they are of USDA ranching initiatives (β = 0.19, p < .001) and state ranching initiatives (β = 0.10, p < .05). In addition, more dependent ranchers are more likely to use multiple and diverse sources of information about ranching (β = 0.18, p < .001), are more likely to realize the severity and extent of the most recent drought's impacts (β = 0.18, p < .001), and were more likely to have a drought management plan in place during the most recent drought (β = 0.18, p < .001). These findings are important in relation to both outreach/extension efforts and rangeland research. Outreach/extension efforts should take into account that people less dependent on their ranches are less aware of resources, as well as, less prepared to adapt to drought. Researchers should control for the extent to which ranchers are dependent on their ranches for income in order to ensure more accurate findings.
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Dairy cattle on Norwegian alpine rangelands – grazing preferences and milk quality
Sickel, H; Abrahamsen, R K; Eldegard, K; Lunnan, T; Norderhaug, A; Petersen, M.A.; Sickel, M.; Steenhuisen, F.; Ohlson, M.
2014-01-01
The results from the study ‘Effects of vegetation and grazing preferences on the quality of alpine dairy products’ will be presented. The main objective of the project was to investigate the connections bet - ween alpine rangeland vegetation, landscape use and grazing preferences of free ranging
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Gillan, Jeffrey K; Karl, Jason W; Duniway, Michael; Elaksher, Ahmed
2014-11-01
Vertical vegetation structure in rangeland ecosystems can be a valuable indicator for assessing rangeland health and monitoring riparian areas, post-fire recovery, available forage for livestock, and wildlife habitat. Federal land management agencies are directed to monitor and manage rangelands at landscapes scales, but traditional field methods for measuring vegetation heights are often too costly and time consuming to apply at these broad scales. Most emerging remote sensing techniques capable of measuring surface and vegetation height (e.g., LiDAR or synthetic aperture radar) are often too expensive, and require specialized sensors. An alternative remote sensing approach that is potentially more practical for managers is to measure vegetation heights from digital stereo aerial photographs. As aerial photography is already commonly used for rangeland monitoring, acquiring it in stereo enables three-dimensional modeling and estimation of vegetation height. The purpose of this study was to test the feasibility and accuracy of estimating shrub heights from high-resolution (HR, 3-cm ground sampling distance) digital stereo-pair aerial images. Overlapping HR imagery was taken in March 2009 near Lake Mead, Nevada and 5-cm resolution digital surface models (DSMs) were created by photogrammetric methods (aerial triangulation, digital image matching) for twenty-six test plots. We compared the heights of individual shrubs and plot averages derived from the DSMs to field measurements. We found strong positive correlations between field and image measurements for several metrics. Individual shrub heights tended to be underestimated in the imagery, however, accuracy was higher for dense, compact shrubs compared with shrubs with thin branches. Plot averages of shrub height from DSMs were also strongly correlated to field measurements but consistently underestimated. Grasses and forbs were generally too small to be detected with the resolution of the DSMs. Estimates of
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International Nuclear Information System (INIS)
Fleischer, Aliza; Sternberg, Marcelo
2006-01-01
Global Climate Change (GCC) can bring about changes in ecosystems and consequently in their services value. Here we show that the urban population in Israel values the green landscape of rangelands in the mesic Mediterranean climate region and is willing to pay for preserving it in light of the expected increasing aridity conditions in this region. Their valuation of the landscape is higher than that of the grazing services these rangelands provide for livestock growers. These results stem from a Time-for-Space approach with which we were able to measure changes in biomass production and rainfall at four experimental sites along an aridity gradient. (author)
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Analytical approaches to quality assurance and quality control in rangeland monitoring data
Producing quality data to support land management decisions is the goal of every rangeland monitoring program. However, the results of quality assurance (QA) and quality control (QC) efforts to improve data quality are rarely reported. The purpose of QA and QC is to prevent and describe non-sampling...
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Holifield Collins, C.; Kautz, M. A.; Skirvin, S. M.; Metz, L. J.
2016-12-01
There are over 180 million hectares of rangelands and grazed forests in the central and western United States. Due to the loss of perennial grasses and subsequent increased runoff and erosion that can degrade the system, woody cover species cannot be allowed to proliferate unchecked. The USDA-Natural Resources Conservation Service (NRCS) has allocated extensive resources to employ brush management (removal) as a conservation practice to control woody species encroachment. The Rangeland-Conservation Effects Assessment Project (CEAP) has been tasked with determining how effective the practice has been, however their land managers lack a cost-effective means to conduct these assessments at the necessary scale. An ArcGIS toolbox for generating large-scale, Landsat-based, spatial maps of woody cover on grazing lands in the western United States was developed through a collaboration with NRCS Rangeland-CEAP. The toolbox contains two main components of operation, image generation and temporal analysis, and utilizes simple interfaces requiring minimum user inputs. The image generation tool utilizes geographically specific algorithms developed from combining moderate-resolution (30-m) Landsat imagery and high-resolution (1-m) National Agricultural Imagery Program (NAIP) aerial photography to produce the woody cover scenes at the Major Land Resource (MLRA) scale. The temporal analysis tool can be used on these scenes to assess treatment effectiveness and monitor woody cover reemergence. RaBET provides rangeland managers an operational, inexpensive decision support tool to aid in the application of brush removal treatments and assessing their effectiveness.
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Resistance to toxic plants: The right animal in the right pasture at the right time
Neurotoxic poisonous plants negatively impact livestock on many western rangelands, which results in annual economic losses of millions of dollars from animal deaths, increased management and treatment costs, and if animals are deferred from grazing, the underutilization of otherwise highly nutritio...
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Study on Rangeland production Potential and its Limitations in the Semi-Arid lands of Northern Kenya
International Nuclear Information System (INIS)
Keya, G.A.; Hornetz, B.
1999-01-01
Results obtained from recent studies focused on rangeland potential as influenced by human activity and climatic factors in the semi-arid and pastoral ecosystems of Northern Kenya indicated great temporal and spatial forage production variability. The objective of the studies was to document the primary production potential in relation to water stress (drought), herbivory and direct human activities. Efforts also focused on finding possibilities of increasing productivity while conserving the finite resources for sustainable use. Laboratory field and numeric methods were employed over several seasons and years. Forb and grass production was more viable than that of the brows (dwarf shrub) layer. Compared to forbs and dwarf shrubs, The grass layer contributed less to the total of production in all seasons, indicating that the region had less potential for grazers compared to browsers. Spatial-temporal variations in rangeland carrying capacity reflected the great spatial heterogeneity in vegetation types and production. Similarly, seasonal difference were very evident, with highest estimates in the long rainy and lowest during the dry and short rainy seasons, respectively. Factors limiting rangeland production potential and were identified to be moisture deficiency, resource-use conflicts, an increasing and partial sedentarised nomadic population, overgrazing, tree felling, and land degradation (desert encroachment). Measures that can increase rangelands production potential and provide a better way of life for the inhabitants of the region include: (a) identification of land degradation (e.g. by means of bio-indicators and Geographical Information systems, GIS); (b) technical interventions (i.e. soil and water conservation,restoration of degraded ares, fodder production); (c)socio-economic interventions (i.e. resolution of resource-use conflicts, alleviation of poverty, infrastructure development, improvement of livestock marketing channels, etc) and (d) continued
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Revolutionary land use change in the 21st century: Is (rangeland) science relevant?
Rapidly increasing demand for food, fiber and fuel together with new technologies and the mobility of global capital are driving revolutionary changes in land use throughout the world. Efforts to increase land productivity include conversion of millions of hectares of rangelands to crop production, ...
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Bridging Drought – Resilience in Rangeland Management in Times of Climate Change
Isele, Judith
2014-01-01
Organic livestock farming in semiarid regions greatly depends on the sustainable management of the natural rangeland as the resource for livestock sustenance. High stock density in combination with short grazing and long recovery periods achieve effective rainfall utilisation and considerably higher fodder production resulting in a high degree of resilience in drought situations.
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CSIR Research Space (South Africa)
Fisher, T
2011-11-01
Full Text Available structure in five communal rangelands around 12 settlements in Bushbuckridge, a municipality in the Kruger to Canyons Biosphere Reserve (South Africa). The importance of underlying abiotic factors was evaluated by measuring size class distributions across...
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Cook, Seth L; Ma, Zhao
2014-02-15
Rangelands can be managed to increase soil carbon and help mitigate emissions of carbon dioxide. This study assessed Utah rangeland owner's environmental values, beliefs about climate change, and awareness of and attitudes towards carbon sequestration, as well as their perceptions of potential policy strategies for promoting carbon sequestration on private rangelands. Data were collected from semi-structured interviews and a statewide survey of Utah rangeland owners, and were analyzed using descriptive and bivariate statistics. Over two-thirds of respondents reported some level of awareness of carbon sequestration and a generally positive attitude towards it, contrasting to their lack of interest in participating in a relevant program in the future. Having a positive attitude was statistically significantly associated with having more "biocentric" environmental values, believing the climate had been changing over the past 30 years, and having a stronger belief of human activities influencing the climate. Respondents valued the potential ecological benefits of carbon sequestration more than the potential financial or climate change benefits. Additionally, respondents indicated a preference for educational approaches over financial incentives. They also preferred to work with a private agricultural entity over a non-profit or government entity on improving land management practices to sequester carbon. These results suggest potential challenges for developing technically sound and socially acceptable policies and programs for promoting carbon sequestration on private rangelands. Potential strategies for overcoming these challenges include emphasizing the ecological benefits associated with sequestering carbon to appeal to landowners with ecologically oriented management objectives, enhancing the cooperation between private agricultural organizations and government agencies, and funneling resources for promoting carbon sequestration into existing land management and
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Directory of Open Access Journals (Sweden)
Jahanbakhsh Pairanj
2011-09-01
Full Text Available This study was carried out in rangelands of Karsanak, Chaharmahal and Bakhtiari province, which is regarded as one of the rich rangelands. Phytogeographically, this region is located in Irano-Turanian (zone of sub alpine. Endemic and rare plants were identified and geographical distribution and life form of identified plant species were investigated as well. Overall, 100 species from 17 families were identified from which 20 percent of identified species was endemic element of Irano-Turanian region. Results indicated that 75.7 percent of identified plants belonged to the Irano-Turanian and only 3 and 2 percent belonged to Euro-Siberian and Mediterranean regions respectively. The reason of high percentage of Irano-Turanian elements is probably the long distance of this region from other regions. Similarities of Irano-Turanian and Mediterranean were included 6.1 percent of identified plants and Irano-Turanian and Euro-Siberian included 2 percent. Results of life forms showed hemichryptophytes including 60 percent of life forms which indicate the cold and mountainous weather.
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Directory of Open Access Journals (Sweden)
Pearson N.S. Mnkeni
2011-05-01
Full Text Available Degradation of soil as a consequence of land use poses a threat to sustainable agriculture in South Africa, resulting in the need for a soil protection strategy and policy. Development of such a strategy and policy require cognisance of the extent and impact of soil degradation processes. One of the identified processes is the decline of soil organic matter, which also plays a central role in soil health or quality. The spatial variability of organic matter and the impact of grazing and burning under rangeland stock production are addressed in this first part of the review. Data from uncoordinated studies showed that South African soils have low organic matter levels. About 58% of soils contain less than 0.5% organic carbon and only 4% contain more than 2% organic carbon. Furthermore, there are large differences in organic matter content within and between soil forms, depending on climatic conditions, vegetative cover, topographical position and soil texture. A countrywide baseline study to quantify organic matter contents within and between soil forms is suggested for future reference. Degradation of rangeland because of overgrazing has resulted in significant losses of soil organic matter, mainly as a result of lower biomass production. The use of fire in rangeland management decreases soil organic matter because litter is destroyed by burning. Maintaining or increasing organic matter levels in degraded rangeland soils by preventing overgrazing and restricting burning could contribute to the restoration of degraded rangelands. This restoration is of the utmost importance because stock farming uses the majority of land in South Africa.
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Climate-change adaptation on rangelands: Linking regional exposure with diverse adaptive capacity
David D. Briske; Linda A. Joyce; H. Wayne Polley; Joel R. Brown; Klaus Wolter; Jack A. Morgan; Bruce A. McCarl; Derek W. Bailey
2015-01-01
The ecological consequences of climate change are predicted to vary greatly throughout US rangelands. Projections show warming and drying in the southern Great Plains and the Southwest, warmer and drier summers with reduced winter snowpack in the Northwest, and warmer and wetter conditions in the northern Great Plains. Primarily through their combined effects on soil...
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Directory of Open Access Journals (Sweden)
F.J. Franco-Guerra
2014-08-01
Full Text Available The objective of the present study was to determine the habits of grazing-browsing by the rate of bites and rate of consumption in the dry matter (MS of the diet of goats under transhumance grazing in mountain rangelands of Nudo Mixteco, being the natural vegetation in the different strata. Six animals of different age and sex were randomly chosen. Direct observation of grazing method was used to determine the rate of bites/min and the rate of consumption by layers. Analyzes of variance was performed and the Tukey test was used for mean comparison test was used (HSD Tukey (α, 0.05. The values of both variables were small, which may be due to the great diversity of plants and their varied morphology which induces the goat won on the one hand to spend more time in the choice of food becoming more selective and on the other, to carry out bites smaller in those plants whose leaf surface is of the type megafilia or in those woody whose leaves are very small (microphilia 2.25 cm2 to 20.25 cm2.
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Multiscale sagebrush rangeland habitat modeling in southwest Wyoming
Homer, Collin G.; Aldridge, Cameron L.; Meyer, Debra K.; Coan, Michael J.; Bowen, Zachary H.
2009-01-01
Sagebrush-steppe ecosystems in North America have experienced dramatic elimination and degradation since European settlement. As a result, sagebrush-steppe dependent species have experienced drastic range contractions and population declines. Coordinated ecosystem-wide research, integrated with monitoring and management activities, would improve the ability to maintain existing sagebrush habitats. However, current data only identify resource availability locally, with rigorous spatial tools and models that accurately model and map sagebrush habitats over large areas still unavailable. Here we report on an effort to produce a rigorous large-area sagebrush-habitat classification and inventory with statistically validated products and estimates of precision in the State of Wyoming. This research employs a combination of significant new tools, including (1) modeling sagebrush rangeland as a series of independent continuous field components that can be combined and customized by any user at multiple spatial scales; (2) collecting ground-measured plot data on 2.4-meter imagery in the same season the satellite imagery is acquired; (3) effective modeling of ground-measured data on 2.4-meter imagery to maximize subsequent extrapolation; (4) acquiring multiple seasons (spring, summer, and fall) of an additional two spatial scales of imagery (30 meter and 56 meter) for optimal large-area modeling; (5) using regression tree classification technology that optimizes data mining of multiple image dates, ratios, and bands with ancillary data to extrapolate ground training data to coarser resolution sensors; and (6) employing rigorous accuracy assessment of model predictions to enable users to understand the inherent uncertainties. First-phase results modeled eight rangeland components (four primary targets and four secondary targets) as continuous field predictions. The primary targets included percent bare ground, percent herbaceousness, percent shrub, and percent litter. The
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Movement and spatial proximity patterns of rangeland-raised Raramuri Criollo cow-calf pairs
The objective of this study was to compare movement patterns of nursing vs. nonnursing mature cows and to characterize cow-calf proximity patterns in two herds of Raramuri Criollo cattle. Herds grazed rangeland pastures in southern New Mexico (4355 ha) and west-central Chihuahua, Mexico (633 ha)'' A...
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Kishor Bhattarai; Shaun Bushman; Douglas A. Johnson; John G. Carman
2011-01-01
Few North American legumes are available for use in rangeland revegetation in the western USA, but Searls prairie clover [Dalea searlsiae (A. Gray) Barneby] is one that holds promise. Commercial-scale seed production of this species could address the issues of unreliable seed availability and high seed costs associated with its wildland seed collection. To evaluate its...
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Directory of Open Access Journals (Sweden)
F. Jafari
2015-03-01
Full Text Available Rangeland condition assessment plays an important role in determining range health and applying appropriate management programs. This study aimed to evaluate the structure and function of a semi-steppe rangeland using Landscape Function Analysis technique (LFA in different land conditions in western Isfahan province, Iran. For this purpose, 4, 3 and 7 sites in different rangeland condition classes including very poor, poor, and moderate were selected respectively. In each site, a 30-meter transect was established and all kinds of patches and inter patches were identified and their lengths and widths were recorded. Also, in each ecological patch, 11 indicators of soil surface characteristics with three replications were measured, and their status was scored according to LFA method. The functionality indices of all the sites including soil stability, infiltration and nutrient cycling were measured. According to the statistical analysis results, most of the structural characteristics (number of patches, patch length, patch area index, landscape organization index and functional indices (infiltration, stability and nutrient cycling status varied significantly (α= 5% between rangeland sites with moderate and very poor condition. The changes of these structural and functional characteristics were not significant between range sites with moderate and poor, and also poor and very poor range conditions. According to the findings of this study, patch types' functionalities did not vary significantly in both rangeland sites with moderate and very poor conditions. The nutrient cycling index in patches formed by ‘forb, shrub and grass’ with poor range condition was significantly more than ‘forb’ and ‘grass’ patches. The study of range site functionality can assist managers in identifying possible ecological thresholds and prioritizing the sub-catchments and vegetation types for implementing range improvement practices.
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Directory of Open Access Journals (Sweden)
Caroline S Archambault
2016-09-01
Full Text Available Throughout the world pastoralists today face a particularly daunting challenge of intensified rangeland fragmentation combined with human population growth and climate change. In many pastoral settings, rangelands are undergoing processes of fragmentation due to tenure transformations, as previously communal lands are privatized into individual holdings. Such processes of enclosure have raised concerns over the long-term costs on pastoral communities and on rangeland eco-systems. This paper explores pastoral responses and adaptations to enclosure based on long-term ethnographic engagement in a Maasai community in Southern Kenya that has recently privatized. Detailed family case studies and herd tracking illuminate the ways in which families try to re-create the commons by relying on social networks for free access to resources. In particular, women’s social networks (for example, their kin, affines, friends, or religious associates seem to play an important role. This paper calls attention to the need to better understand women’s changing roles in pastoral governance and production and the implications these new roles have for women’s well-being and for pastoralism in the face of fragmentation.
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Concentrated flow erosion processes are distinguished from splash and sheetflow processes in their enhanced ability to mobilize and transport large amounts of soil, water and dissolved elements. On rangelands, soil, nutrients and water are scarce and only narrow margins of resource losses are tolera...
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Composted manure application promotes long-term invasion of semi-arid rangeland by Bromus tectorum
Composted organic matter derived from sewage treatment facilities or livestock manure from feedlots is often applied to rangelands of western North America to increase soil fertility, forage production, forage quality, and soil carbon (C) storage. This practice can have a number of undesirable side ...
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Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.
2014-01-01
Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of
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Webb, Nicholas P; Herrick, Jeffrey E; Duniway, Michael C
Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explored how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting, and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass–succulent states across the ecological sites at the plot scale (0.25 ha). We identified vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area could be effectively controlled when bare ground cover was 100 cm in length was less than ∼35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the
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Scales of snow depth variability in high elevation rangeland sagebrush
Tedesche, Molly E.; Fassnacht, Steven R.; Meiman, Paul J.
2017-09-01
In high elevation semi-arid rangelands, sagebrush and other shrubs can affect transport and deposition of wind-blown snow, enabling the formation of snowdrifts. Datasets from three field experiments were used to investigate the scales of spatial variability of snow depth around big mountain sagebrush ( Artemisia tridentata Nutt.) at a high elevation plateau rangeland in North Park, Colorado, during the winters of 2002, 2003, and 2008. Data were collected at multiple resolutions (0.05 to 25 m) and extents (2 to 1000 m). Finer scale data were collected specifically for this study to examine the correlation between snow depth, sagebrush microtopography, the ground surface, and the snow surface, as well as the temporal consistency of snow depth patterns. Variograms were used to identify the spatial structure and the Moran's I statistic was used to determine the spatial correlation. Results show some temporal consistency in snow depth at several scales. Plot scale snow depth variability is partly a function of the nature of individual shrubs, as there is some correlation between the spatial structure of snow depth and sagebrush, as well as between the ground and snow depth. The optimal sampling resolution appears to be 25-cm, but over a large area, this would require a multitude of samples, and thus a random stratified approach is recommended with a fine measurement resolution of 5-cm.
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Millions of hectares of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle &Young) rangeland have been invaded by medusahead (Taeniatherum caput-medusae [L.] Nevski), an exotic annual grass that degrades wildlife habitat, reduces forage production, and decreases biodiversity....
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H. Gyde Lund
2007-01-01
This paper introduces issues surrounding the need for national definitions of forest and rangeland, and it review types of definitions in use, reviews past agreements and their status, and finally gives recommendations as to what should be done next.
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Combined effects of leaf litter and soil microsite on decomposition process in arid rangelands.
Carrera, Analía Lorena; Bertiller, Mónica Beatriz
2013-01-15
The objective of this study was to analyze the combined effects of leaf litter quality and soil properties on litter decomposition and soil nitrogen (N) mineralization at conserved (C) and disturbed by sheep grazing (D) vegetation states in arid rangelands of the Patagonian Monte. It was hypothesized that spatial differences in soil inorganic-N levels have larger impact on decomposition processes of non-recalcitrant than recalcitrant leaf litter (low and high concentration of secondary compounds, respectively). Leaf litter and upper soil were extracted from modal size plant patches (patch microsite) and the associated inter-patch area (inter-patch microsite) in C and D. Leaf litter was pooled per vegetation state and soil was pooled combining vegetation state and microsite. Concentrations of N and secondary compounds in leaf litter and total and inorganic-N in soil were assessed at each pooled sample. Leaf litter decay and soil N mineralization at microsites of C and D were estimated in 160 microcosms incubated at field capacity (16 month). C soils had higher total N than D soils (0.58 and 0.41 mg/g, respectively). Patch soil of C and inter-patch soil of D exhibited the highest values of inorganic-N (8.8 and 8.4 μg/g, respectively). Leaf litter of C was less recalcitrant and decomposed faster than that of D. Non-recalcitrant leaf litter decay and induced soil N mineralization had larger variation among microsites (coefficients of variation = 25 and 41%, respectively) than recalcitrant leaf litter (coefficients of variation = 12 and 32%, respectively). Changes in the canopy structure induced by grazing disturbance increased leaf litter recalcitrance, and reduced litter decay and soil N mineralization, independently of soil N levels. This highlights the importance of the combined effects of soil and leaf litter properties on N cycling probably with consequences for vegetation reestablishment and dynamics, rangeland resistance and resilience with implications
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Revolutionary land use change in the 21st century: Is (rangeland) science relevant?
Herrick, J.E.; Brown, J.R.; Bestelmeyer, B.T.; Andrews, S.S.; Baldi, G.; Davies, J.; Duniway, M.; Havstad, K.M.; Karl, J.W.; Karlen, D.L.; Peters, Debra P.C.; Quinton, J.N.; Riginos, C.; Shaver, P.L.; Steinaker, D.; Twomlow, S.
2012-01-01
Rapidly increasing demand for food, fiber, and fuel together with new technologies and the mobility of global capital are driving revolutionary changes in land use throughout the world. Efforts to increase land productivity include conversion of millions of hectares of rangelands to crop production, including many marginal lands with low resistance and resilience to degradation. Sustaining the productivity of these lands requires careful land use planning and innovative management systems. Historically, this responsibility has been left to agronomists and others with expertise in crop production. In this article, we argue that the revolutionary land use changes necessary to support national and global food security potentially make rangeland science more relevant now than ever. Maintaining and increasing relevance will require a revolutionary change in range science from a discipline that focuses on a particular land use or land cover to one that addresses the challenge of managing all lands that, at one time, were considered to be marginal for crop production. We propose four strategies to increase the relevance of rangeland science to global land management: 1) expand our awareness and understanding of local to global economic, social, and technological trends in order to anticipate and identify drivers and patterns of conversion; 2) emphasize empirical studies and modeling that anticipate the biophysical (ecosystem services) and societal consequences of large-scale changes in land cover and use; 3) significantly increase communication and collaboration with the disciplines and sectors of society currently responsible for managing the new land uses; and 4) develop and adopt a dynamic and flexible resilience-based land classification system and data-supported conceptual models (e.g., state-and-transition models) that represent all lands, regardless of use and the consequences of land conversion to various uses instead of changes in state or condition that are
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Rangeland beef cows spend approximately six months of a typical year raising their calf. This endeavor is known to significantly alter a dam’s grazing behavior and spatial distribution patterns. The objective of this study was to characterize cow-calf contact events in two herds of Raramuri Criollo ...
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Twenty years ago I completed my Master’s work in the Chaco forests of northern Argentina. The native forests are, in fact, rangelands. In addition to livestock grazing, there is timber extraction, wildlife harvest (think tegu lizard cowboy boots), and charcoal production. I took part in a project co...
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Mapping Erosion and Salinity Risk Categories Using GIS and the Rangeland Hydrology Erosion Model
Up to fifteen percent of rangelands in the state of Utah in the United States are classified as being in severely eroding condition. Some of these degraded lands are located on saline, erodible soils of the Mancos Shale formation. This results in a disproportionate contribution of sediment, salinity...
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Kyriazopoulos, Apostolos P; Arabatzis, Garyfallos; Abraham, Eleni M; Parissi, Zoi M
2013-11-15
Rangelands in Greece constitute a very important natural resource as they occupy 40% of the total surface. Not only is their forage production essential for the development of extensive livestock farming, but also they play a key role in outdoor recreational activities, protection from erosion, provision of water supplies and biodiversity conservation. However, land use changes, inappropriate management and wildfires threaten their existence. The research was conducted among the citizens of Viotia prefecture, an area close to Athens, Greece, using personal interviews with a structured questionnaire in 2008. The aim was to record citizens' opinions regarding the threats to rangelands. The results suggest that the main threats as perceived by the respondents, are land use changes especially for urban development, and wildfires. The application of cluster analysis highlighted the differentiation among the respondents in ranking these threats. The more ecologically aware citizens recognised that mismanagement, abandonment and agriculture also threaten rangelands. These threats can have a considerable impact on the lives of the local people. Policy makers and managers should take the opinions of local citizens into consideration, and engage them in decision making so that sustainable management policies could be applied. Copyright © 2013 Elsevier Ltd. All rights reserved.
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A planning support system for rangeland allocation in Iran : case of Chadegan sub-region
Farahpour, M.
2002-01-01
Rangelands, like other natural resources are subject to many changes. In Iran, one of the changes is the land tenure reform, that may have significant effects on both the land and the land user. Land tenure changes not only affect the life of the present, but also that of next generations,
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Sun, Tao; Liu, Zhiyun; Qin, Liping; Long, Ruijun
2012-08-30
Meat safety and nutrition are major concerns of consumers. The development of distinctive poultry production methods based on locally available natural resources is important. Grasshoppers are rich in important nutrients and occur in dense concentrations in most rangelands of northern China. Foraging chickens could be used to suppress grasshopper infestations. However, knowledge of the fatty acid content of meat from free-range broilers reared on alpine rangeland is required. Rearing conditions and diet did not significantly (P > 0.05) affect concentrations of saturated fatty acid (SFA), arachidonic acid, docosahexaenoic acid or the ratio of total n-6 to total n-3 fatty acids. Breast muscle of chickens that had consumed grasshoppers contained significantly (P 0.05) higher than intensively reared birds. Compared with meat from intensively reared birds, meat from free-range broilers had less cholesterol and higher concentrations of total lipid and phospholipids. Chickens eating grasshoppers in rangeland produce superior quality meat and reduce the grasshopper populations that damage the pastures. This provides an economic system of enhanced poultry-meat production, which derives benefits from natural resources rather than artificial additives. Copyright © 2012 Society of Chemical Industry.
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Ranchers that raise Criollo cattle must overcome the challenge of lack of markets for weaned calves. Raramuri Criollo (RC) steers are commonly raised for beef and finished on rangelands, while Corriente (CR) are often raised for rodeo sports. No data exist on weight gains and grazing behavior of ran...
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Ranchers that raise Raramuri Criollo (RC) cattle must overcome the challenge of lack of markets for weaned calves. Growing and finishing RC or RC-crossbred steers on rangeland pastures is increasingly common; however, no data exist on their weight gains or grazing behavior. We tracked the weight a...
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Papanastasis, Vasilios P.; Bautista, Susana; Chouvardas, Dimitrios; Mantzanas, Konstantinos; Papadimitriou, Maria; Garcia Mayor, Angeles; Koukioumi, Polina; Papaioannou, Athanasios; Vallejo, Ramon V.
2017-01-01
Several management actions are applied to restore ecosystem services in degraded Mediterranean rangelands, which range from adjusting the grazing pressure to the removal of grazers and pine plantations. Four such actions were assessed in Quercus coccifera L. shrublands in northern Greece: (i)
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George B. Ruyle
2003-01-01
The Santa Rita Experimental Range (SRER) was established in 1903 at the behest of concerned stockmen and researchers as the first facility in the United States set aside to study range livestock production. At the time, severe overgrazing of the public domain had seriously reduced carrying capacities of Southwestern rangelands. Researchers on the SRER developed and...
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Estimating climate change effects on net primary production of rangelands in the United States
Matthew C. Reeves; Adam L. Moreno; Karen E. Bagne; Steven W. Running
2014-01-01
The potential effects of climate change on net primary productivity (NPP) of U.S. rangelands were evaluated using estimated climate regimes from the A1B, A2 and B2 global change scenarios imposed on the biogeochemical cycling model, Biome-BGC from 2001 to 2100. Temperature, precipitation, vapor pressure deficit, day length, solar radiation, CO2 enrichment and nitrogen...
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Li, Yuan-yuan; Dong, Shi-kui; Wen, Lu; Wang, Xue-xia; Wu, Yu
2013-12-01
Rangeland health assessments play an important role in providing qualitative and quantitative data about ecosystem attributes and rangeland management. The objective of this study is to test the feasible of a modified model and visualize the health in a three-dimensional model. A modified Costanza model was employed, and eight indicators, including the biomass, biodiversity, and carrying capacity [associated with the vigor, organization, and resilience (VOR)] were applied. An entropy method was also developed to calculate the weight of each indicator, and a three-dimensional framework was applied to visualize the indicators and health index. The conceptual model was demonstrated using data from a case study on the alpine rangeland of the Qinghai-Tibetan Plateau, one of the globally important grassland biomes being severely degraded by natural and human factors. The health indices of four grassland plots at different levels of degradation were calculated using a modified approach to measuring their VOR. The results indicated that the least disturbed plot was relatively healthy compared to the other plots. In addition, the health indices presented in the three-dimensional VOR framework decreased in a consistent manner across the four plots along the disturbance gradients. Such rangeland health assessments should be integrated with management efforts to insure their long-term sustainable use.
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Tlili, Abderrazak; Tarhouni, Mohamed; Cardà, Artemi; Neffati, Mohamed
2017-04-01
Climate changes associated with multiple destructive human activities accelerate the degradation process of the natural rangelands around the world and especially the vulnerable areas such as the dryland ecosystems (Anaya-Romero et al., 2015; Eskandari et al., 2016; Muños Rojas et al., 2016; Vicente-Serrano et al., 2016). The vegetation cover and the biomass production of these ecosystems are decreasing and this is resulting in land degradation due to the soil erosion and changes in soil quality due to the abuse and misuse of the soil resources (Cerdà et al., 2016; Prosdocimi et al., 2016; Keesstra et al., 2016). To cope with such threats, it is necessary to develop some management techniques (restoration, plantation…) to enhance the biomass production and the carbon sequestration of the degraded rangelands (Muñoz-Rojas et al., 2016; Tarhouni et al., 2016). The valorization of saline water by planting pastoral halophyte species in salt-affected soils as well as the marginal areas are considered among the valuable tools to increase the rangeland production in dry areas. In this work, the ability of four plants (Atriplex halimus L. (Amaranthaceae), Atriplex mollis Desf. (Amaranthaceae), Lotus creticus L. (Fabaceae) and Cenchrus ciliaris L. (Poaceae)) to grow and to produce are tested under a field saline conditions (water and soil). Non-destructive method (Vegmeasure) is used to estimate the biomass production of these species. Chemical (crude protein, moisture and ash contents) and biochemical analyses (sugars, tannins and polyphenols contents) are also undertaken. Two years after plantation, the obtained results showed the ability of the four species to survive and to grow under high salinity degree. A strong positive correlation was obtained between the canopy cover and the dry biomass of the four studied species. Hence, the restoration of saline soils can be ensured by planting local halophytes. Acknowledgements. The research leading to these results has
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U.S. Environmental Protection Agency — This workbook contains all the activity data, emission factor data, and ancillary data used to compute crop residue burning and rangeland emissions for the 2014 NEI...
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Biomass increases go under cover: woody vegetation dynamics in South African rangelands
CSIR Research Space (South Africa)
Mograbi, PJ
2015-05-01
Full Text Available and ranging (LiDAR) data The communal rangelands were surveyed with airborne laser mapping as part of a Carnegie Airborne Observatory (http://cao.ciw.edu/) campaign in April 2008 and April 2012, concur- rently with the collected fieldwork data in 2012. Small... permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All data necessary to replicate the results of this study are contained within the paper and its...
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Ecological and economic thresholds are important considerations when making decisions about safeguarding or restoring degraded rangelands. When degradation levels have passed a threshold, most managers figure it is either time to take action or too late to take action depending on the particular c...
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A recent study by Davies et al. sought to test whether winter grazing could reduce wildfire size, fire behavior metrics, and fire-induced plant mortality in shrub-grasslands. The authors concluded that ungrazed rangelands may experience more fire-induced mortality of native peren...
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How best to quantify soil seed banks in arid rangelands of the Nama Karoo?
Dreber, Niels
2011-02-01
Sampling design and three sample treatments prior the application of the seedling emergence method were tested in order to find the best method for seed bank quantification in arid Nama Karoo rangelands. I analyzed species composition and seed densities by contrasting undercanopy and open-matrix samples from two soil depths and by comparing the effects of cold-, heat-, and no stratification on germination rates of species in a greenhouse setting. The soil seed bank showed minimal similarity to the standing vegetation, with only 20 plant species germinated. Spatial distribution of seeds was highly heterogeneous. Nearly 90% of germinated seeds were located in 0- to 4-cm compared to >4- to 8-cm soil depth. Undercanopy seed banks contained significantly more species and seeds than open-matrix seed banks. Neither the number nor the diversity of seeds germinated differed significantly among the three treatments. Cold stratification tended to detect more species and seeds only at >4- to 8-cm soil depth. The results highlight the importance of spatial heterogeneity in the accurate evaluation of soil seed banks in the arid Nama Karoo and the importance of considering seasonal variability in the availability of readily germinable seeds. Data also suggest that sample pretreatment in germination trials may give little return for cost and effort, which emphasizes that it is more important to choose the sampling design most likely to give a representative number of seed bank species. Further studies are needed to analyze seed bank dynamics and species-specific germination requirements to promote recruitment of plant taxa underrepresented in the seed bank.
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Bumb, Iris; Garnier, Eric; Coq, Sylvain; Nahmani, Johanne; Del Rey Granado, Maria; Gimenez, Olivier; Kazakou, Elena
2018-03-05
Forage quality for herbivores and litter quality for decomposers are two key plant properties affecting ecosystem carbon and nutrient cycling. Although there is a positive relationship between palatability and decomposition, very few studies have focused on larger vertebrate herbivores while considering links between the digestibility of living leaves and stems and the decomposability of litter and associated traits. The hypothesis tested is that some defences of living organs would reduce their digestibility and, as a consequence, their litter decomposability, through 'afterlife' effects. Additionally in high-fertility conditions the presence of intense herbivory would select for communities dominated by fast-growing plants, which are able to compensate for tissue loss by herbivory, producing both highly digestible organs and easily decomposable litter. Relationships between dry matter digestibility and decomposability were quantified in 16 dominant species from Mediterranean rangelands, which are subject to management regimes that differ in grazing intensity and fertilization. The digestibility and decomposability of leaves and stems were estimated at peak standing biomass, in plots that were either fertilized and intensively grazed or unfertilized and moderately grazed. Several traits were measured on living and senesced organs: fibre content, dry matter content and nitrogen, phosphorus and tannin concentrations. Digestibility was positively related to decomposability, both properties being influenced in the same direction by management regime, organ and growth forms. Digestibility of leaves and stems was negatively related to their fibre concentrations, and positively related to their nitrogen concentration. Decomposability was more strongly related to traits measured on living organs than on litter. Digestibility and decomposition were governed by similar structural traits, in particular fibre concentration, affecting both herbivores and micro
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Feral horses (Equus caballus) are viewed as a symbol of freedom and power; however, they are also a largely unmanaged, non-native grazer in North America, South America, and Australia. Information on their influence on vegetation and soil characteristics in semi-arid rangelands has been limited by ...
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Projected global increases in ruminant numbers and loss of native grasslands will present a number of challenges for livestock agriculture. Escalated demand for livestock products may stimulate interest in using shrubs on western rangelands. A paradigm shift is needed to change the role of shrubs in...
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International Nuclear Information System (INIS)
Ariapour, A; Karami, K; Sadr, A
2014-01-01
One of the most important factors to sustainability utilization of natural potential by rangeland grazing suitability is water resources suitability. This study is a model for quantitative, qualitative and spatial distance assessment of water resource's propriety for goat and cow grazing based on geographic information systems (GIS) in Boroujerd Sarab Sefid rangeland, Lorestan province, Iran 2013. In this research from combining three factors such as quantity, quality and water resource's distances; the final model of degree of propriety of water resources for goat and cow grazing is characterized. Results showed that slope factor was the reason of limitation, and it is considered as a limiting factor in propriety of water resources, so in terms of access to water resources for goat grazing, 4856.4 ha (100%) located in S1 classes and for cow grazing, 4023.14 ha (68.6%) located in S1(suitability) classes, 1,187 ha (20.24%) in S2 classes and 654.8 ha (11.16%) located in S3 classes, respectively for both. So according to the results the rangelands in this region are most suitable for goat because of terrain and weather but this, in combination with, cow hasbandry will allow diversity of economic production and stability of incomes
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Geospatial Data as a Service: The GEOGLAM Rangelands and Pasture Productivity Map Experience
Evans, B. J. K.; Antony, J.; Guerschman, J. P.; Larraondo, P. R.; Richards, C. J.
2017-12-01
Empowering end-users like pastoralists, land management specialists and land policy makers in the use of earth observation data for both day-to-day and seasonal planning needs both interactive delivery of multiple geospatial datasets and the capability of supporting on-the-fly dynamic queries while simultaneously fostering a community around the effort. The use of and wide adoption of large data archives, like those produced by earth observation missions, are often limited by compute and storage capabilities of the remote user. We demonstrate that wide-scale use of large data archives can be facilitated by end-users dynamically requesting value-added products using open standards (WCS, WMS, WPS), with compute running in the cloud or dedicated data-centres and visualizing outputs on web-front ends. As an example, we will demonstrate how a tool called GSKY can empower a remote end-user by providing the data delivery and analytics capabilities for the GEOGLAM Rangelands and Pasture Productivity (RAPP) Map tool. The GEOGLAM RAPP initiative from the Group on Earth Observations (GEO) and its Agricultural Monitoring subgroup aims at providing practical tools to end-users focusing on the important role of rangelands and pasture systems in providing food production security from both agricultural crops and animal protein. Figure 1, is a screen capture from the RAPP Map interface for an important pasture area in the Namibian rangelands. The RAPP Map has been in production for six months and has garnered significant interest from groups and users all over the world. GSKY, being formulated around the theme of Open Geospatial Data-as-a-Service capabilities uses distributed computing and storage to facilitate this. It works behind the scenes, accepting OGC standard requests in WCS, WMS and WPS. Results from these requests are rendered on a web-front end. In this way, the complexities of data locality and compute execution are masked from an end user. On-the-fly computation of
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Oudenhoven, van A.P.E.; Veerkamp, C.J.; Alkemade, Rob; Leemans, Rik
2015-01-01
Over one billion people's livelihoods depend on dry rangelands through livestock grazing and agriculture. Livestock grazing and other management activities can cause soil erosion, increase surface runoff and reduce water availability. We studied the effects of different management regimes on soil
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International Nuclear Information System (INIS)
Ramoelo, A; Madonsela, S; Mathieu, R; Van der Korchove, R; Kaszta, Z; Wolf, E; Cho, M A
2014-01-01
Global change consisting of land use and climate change could have huge impacts on food security and the health of various ecosystems. Leaf nitrogen (N) is one of the key factors limiting agricultural production and ecosystem functioning. Leaf N can be used as an indicator of rangeland quality which could provide information for the farmers, decision makers, land planners and managers. Leaf N plays a crucial role in understanding the feeding patterns and distribution of wildlife and livestock. Assessment of this vegetation parameter using conventional methods at landscape scale level is time consuming and tedious. Remote sensing provides a synoptic view of the landscape, which engenders an opportunity to assess leaf N over wider rangeland areas from protected to communal areas. Estimation of leaf N has been successful during peak productivity or high biomass and limited studies estimated leaf N in dry season. The objective of this study is to monitor leaf N as an indicator of rangeland quality using WorldView 2 satellite images in the north-eastern part of South Africa. Series of field work to collect samples for leaf N were undertaken in the beginning of May (end of wet season) and July (dry season). Several conventional and red edge based vegetation indices were computed. Simple regression was used to develop prediction model for leaf N. Using bootstrapping, indicator of precision and accuracy were analyzed to select a best model for the combined data sets (May and July). The may model for red edge based simple ratio explained over 90% of leaf N variations. The model developed from the combined data sets with normalized difference vegetation index explained 62% of leaf N variation, and this is a model used to estimate and map leaf N for two seasons. The study demonstrated that leaf N could be monitored using high spatial resolution with the red edge band capability
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William R. tech. ed. Meehan
1985-01-01
Although many effects of forest and rangeland management on anadromous fisheries are difficult to measure, economic methods for the evaluation of costs and benefits can be helpful. Such methods can be used to address questions of equity as well as efficiency. Evaluations of equity can show who bears the costs and who captures the benefits of management actions, but...
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John Hof; Curtis Flather; Tony Baltic; Stephen. Davies
1999-01-01
The 1999 forest and rangeland condition indicator model is a set of independent econometric production functions for environmental outputs (measured with condition indicators) at the national scale. This report documents the development of the database and the statistical estimation required by this particular production structure with emphasis on two special...
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Landau, S Y; Dvash, L; Yehuda, Y; Muklada, H; Peleg, G; Henkin, Z; Voet, H; Ungar, E D
2018-02-01
In the context of determining the sustainable carrying capacity of dry-Mediterranean herbaceous rangelands, we examined the effect of animal density on cattle nutrition, which is fundamental to animal performance and welfare. The effects on dietary components of low (0.56 cows/ha; L) and high (1.11 cows/ha; H) animal densities were monitored for three consecutive years in grazing beef cows. In the dry season (summer and early autumn), cows had free access to N-rich poultry litter (PL) given as a dietary supplement. In each season, near-IR spectroscopy (NIRS) was used to predict the chemical composition of herbage samples (ash, NDF, CP, in vitro dry matter digestibility (IVDMD) and metabolizable energy (ME) content from IVDMD). Near-IR spectroscopy was applied also to faecal samples to determine the chemical composition of the diet selected by the animal, as well as the contents of ash, NDF and CP in the faeces themselves. A faecal-NIRS equation was applied to estimate the dietary proportion of PL. Seasonal categories were green, dry without PL supplementation and dry with it. We found no effects of animal density on nutrition during the green season but effects were apparent when cows consumed dry pasture. Ash content predicted by faecal NIRS was higher in the diet than in plant samples clipped from pasture, which infers that cows ingested soil. Dietary and faecal ash contents were higher (Panimals. During the dry period, dietary contents of ME were higher in L than in H (Panimal health, the above results cast doubts on the long-term sustainability of the higher of the animal densities tested. Although it may be sustainable vis-à-vis the vegetation, treatment H may have exceeded the boundaries of what is acceptable for cow health. Chemical information revealed with NIRS can be used to evaluate whether animal densities are compatible with animal health and welfare standards and can play a role in determining the carrying capacity of Mediterranean rangelands.
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Chris Maser; Jack Ward Thomas; Ralph G. Anderson
1984-01-01
The relationships of terrestrial vertebrates to plant communities, structural conditions, and special habitats in the Great Basin of southeastern Oregon are described in a series of appendices. The importance of habitat components to wildlife and the predictability of management activities on wildlife are examined in terms of managed rangelands. ...
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Al-Habsi, Khalid; Yang, Rongchang; Ryan, Una; Jacobson, Caroline; Miller, David W
2017-02-15
Uninucleated Entamoeba cysts measuring 7.3×7.7μm were detected in faecal samples collected from wild Rangeland goats (Capra hircus) after arrival at a commercial goat depot near Geraldton, Western Australia at a prevalence of 6.4% (8/125). Sequences were obtained at the 18S rRNA (n=8) and actin (n=5) loci following PCR amplification. At the 18S locus, phylogenetic analysis grouped the isolates closest with an E. bovis isolate (FN666250) from a sheep from Sweden with 99% similarity. At the actin locus, no E. bovis sequences were available, and the isolates shared 94.0% genetic similarity with E. suis from a pig in Western Japan. This is the first report to describe the morphology and molecular characterisation of Entamoeba from Rangeland goats in Western Australia and the first study to produce actin sequences from E. bovis-like Entamoeba sp. Copyright © 2017 Elsevier B.V. All rights reserved.
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Effects of livestock grazing on grasshopper abundance on a native rangeland in Montana.
O'Neill, Kevin M; Olson, Bret E; Wallander, Roseann; Rolston, Marni G; Seibert, Catherine E
2010-06-01
Livestock grazing can affect habitat quality for grasshoppers through effects on food and oviposition site availability, microclimate, and other factors. Because of this, some authors have suggested that grazing programs can be used to help manage pest grasshopper populations. In a 6-yr study, we controlled access of cattle to replicated experimental plots on an Agropyron spicatum/Poa sandbergii pasture to create consistent year-to-year differences in postgrazing plant cover, with resultant affects on microclimate. After sampling grasshoppers multiple times after grazing treatments each summer, we found evidence of between-treatment differences in grasshopper abundance for the entire assemblage during 4 of the 6 yr. Some species, including Melanoplus sanguinipes (perhaps the worse rangeland grasshopper pest in the western United States), tended to be more abundant on ungrazed plots, whereas Melanoplus gladstoni often had greater densities on heavily-grazed plots. The effect of grazing on grasshopper densities in this study was lower in magnitude and less consistent among years than in a study we conducted simultaneously at a nearby site where the vegetation was dominated by the exotic species crested wheatgrass (Agropyron cristatum). Our results generally support proposals that grazing could be used to reduce pest grasshopper densities, although the effectiveness of a particular grazing scheme may vary among sites, years, and grasshopper and vegetation assemblages.
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Integrated Rangeland Fire Management Strategy Actionable Science Plan Team
2016-01-01
The Integrated Rangeland Fire Management Strategy (hereafter Strategy, DOI 2015) outlined the need for coordinated, science-based adaptive management to achieve long-term protection, conservation, and restoration of the sagebrush (Artemisia spp.) ecosystem. A key component of this management approach is the identification of knowledge gaps that limit...
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Carolyn Hull Sieg
1997-01-01
A strategy for using fire to manage for biological diversity on native rangelands in the Northern Great Plains incorporates an understanding of its past frequency, timing and intensity. Historically, lightning and humans were the major fire setters, and the role of fire varied both in space and time. A burning regime that includes fires at various intervals, seasons...
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Remote sensing data in Rangeland assessment and monitoring
International Nuclear Information System (INIS)
Hamid, Amna Ahmed; Ali, Mohamed M.
1999-01-01
The main objective of the paper is to illustrate the potential of remote sensing data in the study and monitoring of environmental changes in western Sudan where considerable part of the area is under rangeland use. Data from NOAA satellite AVHRR sensor as well as thematic mapper Tm was used to assess the environment of the area during 1982-1997. The AVHRR data was processed into vegetation index (NDVI) images. Image analysis and classification was done using image display and analysis (IDA) GIS method to study vegetation condition in time series. The obtained information from field observations. The result showed high correlation between the information the work concluded the followings: NDVI images and thematic mapper data proved to be efficient in environment change analysis. NOAA AVHRR satellite data can provide an early-warning indicator of an approaching disaster. Remote sensing integrated into a GIS can contribute effectively to improve land management through better understanding of environment variability.(Author)
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Chris Maser; Jack Ward Thomas; Ralph G. Anderson
1984-01-01
The relationships of terrestrial vertebrates to plant communities, structural conditions, and special habitats in the Great Basin of southeastern Oregon are described. The importance of habitat components to wildlife and the predictability of management activities on wildlife are examined in terms of managed rangelands. The paper does not provide guidelines but rather...
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Williams, C. J.; Pierson, F. B.; Al-Hamdan, O. Z.
2014-12-01
Fire is an inherent component of sagebrush steppe rangelands in western North America and can dramatically affect runoff and erosion processes. Post-fire flooding and erosion events pose substantial threats to proximal resources, property, and human life. Yet, prescribed fire can serve as a tool to manage vegetation and fuels on sagebrush rangelands and to reduce the potential for large catastrophic fires and mass erosion events. The impact of burning on event hydrologic and erosion responses is strongly related to the degree to which burning alters vegetation, ground cover, and surface soils and the intensity and duration of precipitation. Fire impacts on hydrologic and erosion response may be intensified or reduced by inherent site characteristics such as topography and soil properties. Parameterization of these diverse conditions in predictive tools is often limited by a lack of data and/or understanding for the domain of interest. Furthermore, hydrologic and erosion functioning change as vegetation and ground cover recover in the years following burning and few studies track these changes over time. In this study, we evaluated the impacts of prescribed fire on vegetation, ground cover, soil water repellency, and hydrologic and erosion responses 1, 2, and 5 yr following burning of a mountain big sagebrush community on steep hillslopes with fine-textured soils. The study site is within the Reynolds Creek Experimental Watershed, southwestern Idaho, USA. Vegetation, ground cover, and soil properties were measured over plot scales of 0.5 m2 to 9 m2. Rainfall simulations (0.5 m2) were used to assess the impacts of fire on soil water repellency, infiltration, runoff generation, and splash-sheet erosion. Overland flow experiments (9 m2) were used to assess the effects of fire-reduced ground cover on concentrated-flow runoff and erosion processes. The study results provide insight regarding fire impacts on runoff, erosion, and soil water repellency in the immediate and
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Stavi, Ilan; Barkai, Daniel; Knoll, Yaakov M.; Glion, Hiam Abu; Katra, Itzhak; Brook, Anna; Zaady, Eli
2017-03-01
An unintended fire outbreak during summer 2015 in the semi-arid Israeli Negev resulted in the burning of extensive croplands and rangelands. The rangelands have been managed over the long term for occasional grazing, while the croplands have been utilized for rainfed wheat cropping. Yet, during the studied year, the croplands were left fallow, allowing the growth of herbaceous vegetation, which was harvested and baled for hay before the fire outbreak. The study objectives were to investigate the impacts of fire, land-use, and soil depth on water-repellency and on the status and dynamics of some of the most important organic and mineral soil resources. Additionally, we aimed to assess the severity of this fire outbreak. The soil-water repellency was studied by measuring the soil's water drop penetration time (WDPT) and critical surface tension (CST). A significant effect of fire on soil hydrophobicity was recorded, with a slight increase in mean WDPT and a slight decrease in mean CST in the burnt sites than in the non-burnt sites. Yet, soil hydrophobicity in the burnt lands was rather moderate and remained within the water repellency's lowest class. A significant effect of land-use on the means of WDPT and CST was also recorded, being eleven-fold greater and 7% smaller, respectively, in the rangelands than in the croplands. This is consistent with the almost eightfold greater mean above-ground biomass recorded in the non-burnt rangelands than in the non-burnt post-harvest croplands, revealing the positive relations between available fuel load and soil-water repellency. The effect of soil depth was significant for CST but not for WDPT. Overall, the gathered data suggest that fire severity was low to moderate. Fire was also found to significantly affect the fire severity only slightly increased the soil water repellency, and at the same time, increased on-site availability of some important soil resources. Nevertheless, it is acknowledged that such fires could impose
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International Nuclear Information System (INIS)
Ritchie, Jerry C.; Nearing, Mark A.; Rhoton, Fred E.
2009-01-01
Analysis of soil redistribution and sediment sources in semiarid and arid watersheds provides information for implementing management practices to improve rangeland conditions and reduce sediment loads to streams. The purpose of this research was to develop sediment budgets and identify potential sediment sources using 137 Cs and other soil properties in a series of small semiarid subwatersheds on the USDA ARS Walnut Gulch Experimental Watershed near Tombstone, Arizona, USA. Soils were sampled in a grid pattern on two small subwatersheds and along transects associated with soils and geomorphology on six larger subwatersheds. Soil samples were analyzed for 137 Cs and selected physical and chemical properties (i.e., bulk density, rocks, particle size, soil organic carbon). Suspended sediment samples collected at measuring flume sites on the Walnut Gulch Experimental Watershed were also analyzed for these properties. Soil redistribution measured using 137 Cs inventories for a small shrub-dominated subwatershed and a small grass-dominated subwatershed found eroding areas in these subwatersheds were losing -5.6 and -3.2 t ha -1 yr -1 , respectively; however, a sediment budget for each of these subwatersheds, including depositional areas, found net soil loss to be -4.3 t ha -1 yr -1 from the shrub-dominated subwatershed and -0.1 t ha -1 yr -1 from the grass-dominated subwatershed. Generally, the suspended sediment collected at the flumes of the six other subwatersheds was enriched in silt and clay. Using a mixing model to determine sediment source indicated that shrub-dominated subwatersheds were contributing most of the suspended sediment that was measured at the outlet flume of the Walnut Gulch Experimental Watershed. The two methodologies (sediment budgets and sediment source analyses) indicate that shrub-dominated systems provide more suspended sediment to the stream systems. The sediment budget studies also suggest that sediment yields measured at the outlet of a
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Carbon transport by symbiotic fungi in fourwing saltbush, Atriplex canescens (Pursh) Nutt
Jerry R. Barrow
2001-01-01
Mycorrhizal fungi enhance the nutrition and survival of host plants in native ecosystems. Arid rangelands severely challenge plants because of chronic nutrient and water stress. Fourwing saltbush, Atriplex canescens (Pursh) Nutt., a dominant and important shrub of western arid rangelands, generally considered to be non-mycorrhizal, is more extensively colonized by dark...
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Herguido, Estela; Pulido, Manuel; Francisco Lavado Contador, Joaquín; Schnabel, Susanne
2017-04-01
In Iberian dehesas and montados, the lack of tree recruitment compromises its long-term sustainability. However, in marginal areas of dehesas shrub encroachment facilitates tree recruitment while altering the distinctive physiognomic and cultural characteristics of the system. These are ongoing processes that should be considered when designing afforestation measures and policies. Based on spatial variables, we modeled the proneness of a piece of land to undergo tree recruitment and the results were related with the afforestation measures carried out under the UE First Afforestation Agricultural Land Program between 1992 and 2008. We analyzed the temporal tree population dynamics in 800 randomly selected plots of 100 m radius (2,510 ha in total) in dehesas and treeless pasturelands of Extremadura (hereafter rangelands). Tree changes were revealed by comparing aerial images taken in 1956 with orthophotographs and infrared ones from 2012. Spatial models that predict the areas prone either to lack tree recruitment or with recruitment were developed and based on three data mining algorithms: MARS (Multivariate Adaptive Regression Splines), Random Forest (RF) and Stochastic Gradient Boosting (Tree-Net, TN). Recruited-tree locations (1) vs. locations of places with no recruitment (0) (randomly selected from the study areas) were used as the binary dependent variable. A 5% of the data were used as test data set. As candidate explanatory variables we used 51 different topographic, climatic, bioclimatic, land cover-related and edaphic ones. The statistical models developed were extrapolated to the spatial context of the afforested areas in the region and also to the whole Extremenian rangelands, and the percentage of area modelled as prone to tree recruitment was calculated for each case. A total of 46,674.63 ha were afforested with holm oak (Quercus ilex) or cork oak (Quercus suber) in the studied rangelands under the UE First Afforestation Agricultural Land Program. In
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Patricia Gradek; Lawrence Saslaw; Steven Nelson
1989-01-01
The Bakersfield District of the Bureau of Land Management conducted an inventory of rangeland riparian systems using a new method developed by a Bureau-wide task force to inventory, monitor and classify riparian areas. Data on vegetation composition were collected for 65 miles of streams and entered into a hierarchical vegetation classification system. Ratings of...
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CSIR Research Space (South Africa)
Ramoelo, Abel
2012-10-01
Full Text Available and grass quantity, respectively. The objective of the study is to estimate and map leaf N and biomass as an indicator of rangeland quality and quantity using vegetation indices derived from one RapidEye image taken at peak productivity. The study...
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Opiyo, Francis EO; Ekaya, Wellington N; Nyariki, Dickson M; Mureithi, Stephen Mwangi
2011-01-01
Semi-arid rangelands in Kenya are an important source of forage for both domestic and wild animals. However, indigenous perennial grasses notably Cenchrus ciliaris (African foxtail grass), Eragrostis superba (Maasai love grass) and Enteropogon macrostachyus (Bush rye grass) are disappearing at an alarming rate. Efforts to re-introduce them through restoration programs have often yielded little success. This can partly be attributed to failure of topsoil to capture and store scarce water to me...
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Assessment of Landsat multispectral scanner spectral indexes for monitoring arid rangeland
Musick, H. B.
1984-01-01
Correlations between spectral indices and vegetation parameters in south-central New Mexico were used to determine the utility of Landsat Multispectral Scanner (MSS) spectral indices in arid rangeland monitoring. In addition, spectral index change for 1976-1980 was calculated from retrospective MSS data and compared with qualitative ground truth in order to evaluate vegetation change detection by means of spectral indices. Brightness index change consistently differentiated between cover increase and decrease, but index change appears to have been offset from true cover change; this may at least partly be attributed to the failure of the methods used to standardize MSS scenes for differences in sensor response. Green vegetation indices, by contrast to brightness indices, failed to consistently differentiate between cover increase and decrease.
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Matt Reeves; Leonardo Frid
2016-01-01
Rangeland landscapes occupy roughly 662 million acres in the coterminous U.S. (Reeves and Mitchell 2011) and their vegetation responds quickly to climate and management, with high relative growth rates and inter-annual variability. Current national decision support systems in the U.S. such as the Interagency Fuels Treatment Decision Support System (IFT-DSS) require...
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Ngondya, Issakwisa B; Munishi, Linus K; Treydte, Anna C; Ndakidemi, Patrick A
2016-01-01
The invasive weed species Gutenbergia cordifolia has been observed to suppress native plants and to dominate more than half of the entire crater floor (250 km 2 ) in the Ngorongoro Conservation Area (NCA). As this species has been found to be toxic to ruminants it might strongly impact animal populations in this ecologically diverse ecosystem. Hence, a nature-based approach is urgently needed to manage its spread. We tested two Desmodium spp extracts applied to G. cordifolia and assessed the latter's germination rate, height, fresh weight and leaf total chlorophyll content after 30 days in both laboratory and screen house experiments. Seedling germination rate was halved by Desmodium uncinatum leaf extract (DuL), particularly under higher concentrations (≥75 %) rather than lower concentrations (≤62.5 %). Likewise, in both laboratory and screen house experiments, germination rate under DuL treatments declined with increasing concentrations. Seedling height, fresh weight and leaf total chlorophyll content (Chl) were also most strongly affected by DuL treatments rather than D. uncinatum root extract, Desmodium intortum leaf extract or D. intortum root extract treatments. Generally, seedlings treated with higher DuL concentrations were half as tall, had one-third the weight and half the leaf Chl content compared to those treated with lower concentrations. Our study shows a novel technique that can be applied where G. cordifolia may be driving native flora and fauna to local extinction. Our data further suggest that this innovative approach is both ecologically safe and effective and that D. uncinatum can be sustainably used to manage invasive plants, and thus, to improve rangeland productivity.
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Pulido-Fernández, Manuel; Schnabel, Susanne; Francisco Lavado-Contador, Joaquín
2014-05-01
Rangelands cover vast extensions of land in Spain (>90,000 km2), where a total amount of 13 millions of domestic animals graze extensively their pastures. By clear-cutting shrubs, removing selected trees and by cultivation, these rangelands were created from former Mediterranean oak forests, mainly composed by holm oak and cork oak (Quercus ilex rotundifolia and Q. suber) as tree species, Nowadays this land system is exploited economically in large farms (>100 ha), most of them held on private ownership (80% of total) and dedicated to extensive ranching. Overgrazing is common and the excessive stocking rates may deteriorate soil quality, causing economic losses and environmental damage. Many studies have been developed on the effects of livestock grazing over soil properties and degradation processes, most of them by only comparing extreme cases (e.g. ungrazed vs. grazed or overgrazed areas). The main goal of this study is to contribute to the understanding on how animal grazing affects soil properties and degradation processes. The study is particularly focused on soil compaction and sheet erosion as related to the reduction of vegetation cover by defoliation. Soil properties were analysed from 119 environmental units selected from 56 farms distributed throughout the region of Extremadura (SW Spain). The units are representative of different rangeland types, i.e. scrublands of Retama sphaerocarpa, dehesas (wooded rangelands) and treeless grasslands. Soil surface cover was determined along transects in September 2010 (antecedent rainfall: 413-923 mm) considering the following classes: bare ground, grasses, mosses, litter, stones (<2 mm) and rock outcrops. Farmer interviews were also conducted in order to quantify stocking rates and to assess land management in 12 out of 56 farms. In the farms where transects and farmer interviews could not be carried out, bare soil surface and livestock densities were estimated. Bare soil surface was determined by classifying
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Spatial distribution of overland flow and sediment yield in semi-arid rangelands
International Nuclear Information System (INIS)
Sarah, P.; Lavee, H.
2009-01-01
Feedbacks and mutual links exist among soil, vegetation and water; they enable co-evolution of these features within eco-geomorphic systems, These relations are fragile, especially in semi-arid areas where grazing is the main land use. The simples subdivision of the surface of many semi-arid rangelands is into a two-component mosaic pattern comprising shrub patches interspersed with open spaces, with the former acting s skinks for water and other resources, and the latter as sources. However close observations in areas under grazing in the northern Negev region of Israel suggested that the spatial patterns of surface components is more complicated, and that the open space between shrubs consists of two components: herbaceous areas, separated by trampling routes that support no vegetation. (Author)
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Environmentally Optimal, Nutritionally Aware Beef Replacement Plant-Based Diets.
Eshel, Gidon; Shepon, Alon; Noor, Elad; Milo, Ron
2016-08-02
Livestock farming incurs large and varied environmental burdens, dominated by beef. Replacing beef with resource efficient alternatives is thus potentially beneficial, but may conflict with nutritional considerations. Here we show that protein-equivalent plant based alternatives to the beef portion of the mean American diet are readily devisible, and offer mostly improved nutritional profile considering the full lipid profile, key vitamins, minerals, and micronutrients. We then show that replacement diets require on average only 10% of land, 4% of greenhouse gas (GHG) emissions, and 6% of reactive nitrogen (Nr) compared to what the replaced beef diet requires. Applied to 320 million Americans, the beef-to-plant shift can save 91 million cropland acres (and 770 million rangeland acres), 278 million metric ton CO2e, and 3.7 million metric ton Nr annually. These nationwide savings are 27%, 4%, and 32% of the respective national environmental burdens.
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Niane, A.A.
2013-01-01
Keywords: Rotational grazing, full protection, continuous grazing species richness,
species diversity, soil seed bank, Bayesian methods, Salsola vermiculata, seed
longevity, rangeland management, Syria.
Rangelands represent 70% of the semi-arid and arid
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Multifrequency passive microwave observations of soil moisture in an arid rangeland environment
Jackson, T. J.; Schmugge, T. J.; Parry, R.; Kustas, W. P.; Ritchie, J. C.; Shutko, A. M.; Khaldin, A.; Reutov, E.; Novichikhin, E.; Liberman, B.
1992-01-01
A cooperative experiment was conducted by teams from the U.S. and U.S.S.R. to evaluate passive microwave instruments and algorithms used to estimate surface soil moisture. Experiments were conducted as part of an interdisciplinary experiment in an arid rangeland watershed located in the southwest United States. Soviet microwave radiometers operating at wavelengths of 2.25, 21 and 27 cm were flown on a U.S. aircraft. Radio frequency interference limited usable data to the 2.25 and 21 cm systems. Data have been calibrated and compared to ground observations of soil moisture. These analyses showed that the 21 cm system could produce reliable and useful soil moisture information and that the 2.25 cm system was of no value for soil moisture estimation in this experiment.
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Ewe productivity (i.e., total numbers or weight of lamb weaned ÷ number of breeding ewes) is a key indicator of lamb production efficiency. This second-generation study compared various measures of ewe productivity and ewe and lamb performance in an extensive rangeland production system of ewes of 3...
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Directory of Open Access Journals (Sweden)
M. Salarvand
2016-09-01
Full Text Available This study aimed to compare plant species diversity indices (diversity and richness and some physico-chemical properties of soil among forest, ecotone and rangeland habitats. Vegetation sampling was done randomly at each habitat. One dominant community was selected in each habitat and one key area was distinguished in each community and 8×1m2 plots were randomly established in each key area. In each plot, the list of existing plants and cover percentage for each species were determined and soil samples were taken from depths of 0-10 cm. The Shannon-Wiener and Simpson diversity indices and Margalef and Menhinic richness indices were estimated using PAST software. Physical and chemical characteristics of the soil were compared at three sites by analysis of variance (One Way ANOVA. The results showed that the lowest and highest values of all species diversity and richness were occurred in forest and ecotone habitats, respectively. Bulk density, sand and pH value of soil were significantly the highest in the rangeland. The percentage of clay and organic carbon in forest habitat were higher than the two other habitats. This study revealed the importance of ecotone in preserving the diversity and species richness.
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Wang, Bin; Waters, Cathy; Orgill, Susan; Gray, Jonathan; Cowie, Annette; Clark, Anthony; Liu, De Li
2018-07-15
Efficient and effective modelling methods to assess soil organic carbon (SOC) stock are central in understanding the global carbon cycle and informing related land management decisions. However, mapping SOC stocks in semi-arid rangelands is challenging due to the lack of data and poor spatial coverage. The use of remote sensing data to provide an indirect measurement of SOC to inform digital soil mapping has the potential to provide more reliable and cost-effective estimates of SOC compared with field-based, direct measurement. Despite this potential, the role of remote sensing data in improving the knowledge of soil information in semi-arid rangelands has not been fully explored. This study firstly investigated the use of high spatial resolution satellite data (seasonal fractional cover data; SFC) together with elevation, lithology, climatic data and observed soil data to map the spatial distribution of SOC at two soil depths (0-5cm and 0-30cm) in semi-arid rangelands of eastern Australia. Overall, model performance statistics showed that random forest (RF) and boosted regression trees (BRT) models performed better than support vector machine (SVM). The models obtained moderate results with R 2 of 0.32 for SOC stock at 0-5cm and 0.44 at 0-30cm, RMSE of 3.51MgCha -1 at 0-5cm and 9.16MgCha -1 at 0-30cm without considering SFC covariates. In contrast, by including SFC, the model accuracy for predicting SOC stock improved by 7.4-12.7% at 0-5cm, and by 2.8-5.9% at 0-30cm, highlighting the importance of including SFC to enhance the performance of the three modelling techniques. Furthermore, our models produced a more accurate and higher resolution digital SOC stock map compared with other available mapping products for the region. The data and high-resolution maps from this study can be used for future soil carbon assessment and monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.
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The geomorphic legacy of water and erosion control structures in a semiarid rangeland watershed
Nichols, Mary H.; Magirl, Christopher S.; Sayre, N.F.; Shaw, Jeremy R.
2018-01-01
Control over water supply and distribution is critical for agriculture in drylands where manipulating surface runoff often serves the dual purpose of erosion control. However, little is known of the geomorphic impacts and legacy effects of rangeland water manipulation infrastructure, especially if not maintained. This study investigated the geomorphic impacts of structures such as earthen berms, water control gates, and stock tanks, in a semiarid rangeland in the southwestern USA that is responding to both regional channel incision that was initiated over a century ago, and a more recent land use change that involved cattle removal and abandonment of structures. The functional condition of remnant structures was inventoried, mapped, and assessed using aerial imagery and lidar data. Headcut initiation, scour, and channel incision associated with compromised lateral channel berms, concrete water control structures, floodplain water spreader berms, and stock tanks were identified as threats to floodplains and associated habitat. Almost half of 27 identified lateral channel berms (48%) have been breached and 15% have experienced lateral scour; 18% of 218 shorter water spreader berms have been breached and 17% have experienced lateral scour. A relatively small number of 117 stock tanks (6%) are identified as structurally compromised based on analysis of aerial imagery, although many currently do not provide consistent water supplies. In some cases, the onset of localized disturbance is recent enough that opportunities for mitigation can be identified to alter the potentially damaging erosion trajectories that are ultimately driven by regional geomorphic instability. Understanding the effects of prior land use and remnant structures on channel and floodplain morphologic condition is critical because both current land management and future land use options are constrained by inherited land use legacy effects.
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Directory of Open Access Journals (Sweden)
Andreas Tewes
2015-05-01
Full Text Available Image time series of high temporal and spatial resolution capture land surface dynamics of heterogeneous landscapes. We applied the ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model algorithm to multi-spectral images covering two semi-arid heterogeneous rangeland study sites located in South Africa. MODIS 250 m resolution and RapidEye 5 m resolution images were fused to produce synthetic RapidEye images, from June 2011 to July 2012. We evaluated the performance of the algorithm by comparing predicted surface reflectance values to real RapidEye images. Our results show that ESTARFM predictions are accurate, with a coefficient of determination for the red band 0.80 < R2 < 0.92, and for the near-infrared band 0.83 < R2 < 0.93, a mean relative bias between 6% and 12% for the red band and 4% to 9% in the near-infrared band. Heterogeneous vegetation at sub-MODIS resolution is captured adequately: A comparison of NDVI time series derived from RapidEye and ESTARFM data shows that the characteristic phenological dynamics of different vegetation types are reproduced well. We conclude that the ESTARFM algorithm allows us to produce synthetic remote sensing images at high spatial combined with high temporal resolution and so provides valuable information on vegetation dynamics in semi-arid, heterogeneous rangeland landscapes.
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Herbaceous Legume Encroachment Reduces Grass Productivity and Density in Arid Rangelands.
Directory of Open Access Journals (Sweden)
Thomas C Wagner
Full Text Available Worldwide savannas and arid grasslands are mainly used for livestock grazing, providing livelihood to over a billion people. While normally dominated by perennial C4 grasses, these rangelands are increasingly affected by the massive spread of native, mainly woody legumes. The consequences are often a repression of grass cover and productivity, leading to a reduced carrying capacity. While such encroachment by woody plants has been extensively researched, studies on similar processes involving herbaceous species are rare. We studied the impact of a sustained and massive spread of the native herbaceous legume Crotalaria podocarpa in Namibia's escarpment region on the locally dominant fodder grasses Stipagrostis ciliata and Stipagrostis uniplumis. We measured tussock densities, biomass production of individual tussocks and tussock dormancy state of Stipagrostis on ten 10 m x 10 m plots affected and ten similarly-sized plots unaffected by C. podocarpa over eight consecutive years and under different seasonal rainfalls and estimated the potential relative productivity of the land. We found the percentage of active Stipagrostis tussocks and the biomass production of individual tussocks to increase asymptotically with higher seasonal rainfall reaching a maximum around 300 mm while the land's relative productivity under average local rainfall conditions reached only 40% of its potential. Crotalaria podocarpa encroachment had no effect on the proportion of productive grass tussocks, but reduced he productivity of individual Stipagrostis tussocks by a third. This effect of C. podocarpa on grass productivity was immediate and direct and was not compensated for by above-average rainfall. Besides this immediate effect, over time, the density of grass tussocks declined by more than 50% in areas encroached by C. podocarpa further and lastingly reducing the lands carrying capacity. The effects of C. podocarpa on grass productivity hereby resemble those of woody
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Olexa, Edward M.; Lawrence, Rick L
2014-01-01
Federal land management agencies provide stewardship over much of the rangelands in the arid andsemi-arid western United States, but they often lack data of the proper spatiotemporal resolution andextent needed to assess range conditions and monitor trends. Recent advances in the blending of com-plementary, remotely sensed data could provide public lands managers with the needed information.We applied the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) to five Landsat TMand concurrent Terra MODIS scenes, and used pixel-based regression and difference image analyses toevaluate the quality of synthetic reflectance and NDVI products associated with semi-arid rangeland. Pre-dicted red reflectance data consistently demonstrated higher accuracy, less bias, and stronger correlationwith observed data than did analogous near-infrared (NIR) data. The accuracy of both bands tended todecline as the lag between base and prediction dates increased; however, mean absolute errors (MAE)were typically ≤10%. The quality of area-wide NDVI estimates was less consistent than either spectra lband, although the MAE of estimates predicted using early season base pairs were ≤10% throughout the growing season. Correlation between known and predicted NDVI values and agreement with the 1:1regression line tended to decline as the prediction lag increased. Further analyses of NDVI predictions,based on a 22 June base pair and stratified by land cover/land use (LCLU), revealed accurate estimates through the growing season; however, inter-class performance varied. This work demonstrates the successful application of the STARFM algorithm to semi-arid rangeland; however, we encourage evaluation of STARFM’s performance on a per product basis, stratified by LCLU, with attention given to the influence of base pair selection and the impact of the time lag.
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Mapping Erosion Risk in California's Rangelands Using the Universal Soil Loss Equation (USLE)
Salls, W. B.; O'Geen, T. T.
2015-12-01
Soil loss constitutes a multi-faceted problem for agriculture: in addition to reducing soil fertility and crop yield, it compromises downstream water quality. Sediment itself is a major issue for aquatic ecosystems, but also serves as a vector for transporting nutrients, pesticides, and pathogens. Rangelands are thought to be a contributor to water quality degradation in California, particularly in the northern Coast Range. Though total maximum daily loads (TMDLs) have been imposed in some watersheds, and countless rangeland water quality outreach activities have been conducted, the connection between grazing intensity recommendations and changes in water quality is poorly understood at the state level. This disconnect gives rise to poorly informed regulations and discourages adoption of best management practices by ranchers. By applying the Universal Soil Loss Equation (USLE) at a statewide scale, we highlighted areas most prone to erosion. We also investigated how two different grazing intensity scenarios affect modeled soil loss. Geospatial data layers representing the USLE parameters—rainfall erosivity, soil erodibility, slope length and steepness, and cover—were overlaid to model annual soil loss. Monitored suspended sediment data from a small North Coast watershed with grazing as the predominant land use was used to validate the model. Modeled soil loss values were nearly one order of magnitude higher than monitored values; average soil loss feeding the downstream-most site was modeled at 0.329 t ha-1 yr-1, whereas storm-derived sediment passing the site over two years was calculated to be 0.037 t ha-1 yr-1. This discrepancy may stem from the fact that the USLE models detached sediment, whereas stream monitoring reflects sediment detached and subsequently transported to the waterway. Preliminary findings from the statewide map support the concern that the North Coast is particularly at risk given its combination of intense rain, erodible soils, and
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Effects of land use change and management on SOC and soil quality in Mediterranean rangelands areas
Parras-Alcántara, Luis; Lozano-García, Beatriz; Requejo, Ana; Zornoza, Raúl
2017-04-01
INTRODUCTION Rangelands in the Iberian Peninsula occupy more than 90,000 km2. These rangelands were created from the former Mediterranean oak forests, mainly composed of holm oak and cork oak (Quercus ilex rotundifolia and Quercus suber), by clear-cutting shrubs, removing selected trees and cultivating. These man-made landscapes are called 'dehesas' in Spain and 'montados' in Portugal. Between 1955 and 1981, more than 5,000 km2 of dehesas was converted from pastureland to cultivated land. This process has been accelerated since 1986 owing to subsidies from the European Common Agricultural Policy (Parras-Alcántara et al., 2015a). The role that natural rangelands play in the global carbon cycle is extremely important, accounting for 10-30% of the world's total soil organic carbon (SOC), in addition, SOC concentration is closely related to soil quality and vegetation productivity (Brevik, 2012). Therefore, to study the land use and management changes is important, particularly in Mediterranean soils, as they are characterized by low organic carbon content, furthermore, the continuous use of ploughing for grain production is the principal cause of soil degradation. Therefore, land use decisions and management systems can increase or decrease SOC content and stock (Corral-Fernández et al., 2013; Parras-Alcántara et al., 2014, 2015a and 2015b; Parras-Alcántara and Lozano-García, 2014) MATERIAL AND METHODS A field study was conducted to determine the land use change (Mediterranean evergreen oak woodland to olive grove and cereal, all of them managed under conventional tillage and under conservationist practices) effects on SOC stocks and the soil quality (Stratification Ratio) in Los Pedroches valley, southern Spain. RESULTS Results for the present study indicate that management practices had little effect on SOC storage in dehesas. The stratification ratio was >2 both under conventional tillage and under organic farming, so, soils under dehesa had high quality
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Goodrich, D. C.; Heilman, P.; Nearing, M.; Speath, K.; Hernandez, M.; Wei, H.; Holifield-Collins, C.; Kautz, M.; Nichols, M.; Barlow, J.; Guertin, P.; Burns, S.; Stone, J. J.; Weltz, M.; Metz, L.; Norfleet, L.; Duriancik, L.; Johnson, M.
2013-12-01
Farm Bill legislation enacted by Congress in 2002 directed the U.S. Department of Agriculture to assess of the benefits and efficacy of conservation practices provided by a variety of USDA programs. Benefits include improved agricultural production, reduction of erosion and associated nutrient losses, improved water quality, improved soil resilience, and improved habitat among others. To conduct the assessment, the USDA initiated CEAP or the Conservation Effects Assessment Project in 2003, which included a national assessment complemented by small watershed studies. The national assessment started in eastern and midwestern cultivated croplands and has now progressed to western rangelands. This presentation will discuss the challenges of assessing the effects of rangeland conservation practices in a period of unusually hot and dry climatic conditions in the Cienega Creek Watershed (CCW) located southeast of Tucson, Arizona. As is common in the western U.S., the CCW consists of a patchwork of private and public lands in the west with much of the public lands leased for grazing cattle. The watershed also has high recreational value and provides many ecosystem services, including wildlife habitat qualities and flood protection to Tucson. A combination of monitoring, modeling, and remote sensing was utilized in the assessment. Conservation spending in the watershed ramped up in 1997. However, the 16-year period from 1997-2012 contains almost half of the 23 driest seasons (lowest 20 percentile) from the 117-year observed precipitation record. Initial results indicate that Landsat remotely sensed images can be effectively used to estimate both green and senescent canopy cover. This enabled detection of the impacts of drought and changes in canopy cover from practices such as prescribed fire and mechanical brush removal. Cienega Creek Watershed - Land Ownership
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Population structures of Astragalus filipes collections from western North America
B. Shaun Bushman; Kishor Bhattarai; Douglas A. Johnson
2010-01-01
The majority of species used for revegetation in semi-arid western rangelands of North America are grasses, with few forbs and nearly no legumes. Astragalus filipes (Torr. Ex A. Gray) is a western North American legume and a promising candidate for use in rangeland revegetation, but assessments of plant species diversity and structure are necessary to determine which...
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Energy Technology Data Exchange (ETDEWEB)
Boufennara, S.; Lopez, S.; Boussebouna, H.; Bodas, R.; Bouazza, L.
2012-11-01
Many wild browse and bush species are undervalued mainly because of insufficient knowledge about their potential feeding value. The objective was to evaluate some nutritional attributes of various Algerian browse and shub species (Atriplex halimus, Artemisia campestris, Artemisia herba-alba, Astragalus gombiformis, Calobota saharae, Retama raetam, Stipagrostis pungens, Lygeum spartum and Stipa tenacissima). Chemical composition, phenols and tannins concentration, in vitro digestibility, in vitro gas production kinetics and in vitro bio-assay for assessment of tannins using buffered rumen fluid, and in situ disappearence of the edible parts of the plants (leaves, thin twigs and flowers) were determined. In general, protein content in dicotyledon species was always greater than in monocotyledon grasses, these showing higher neutral and acid detergent fibre and lower lignin contents than dicots. The tannin concentrations varied considerably between species, but in general the plants investigated in this study had low tannin contents (except for Artemisia spp. and S. tenacissima). Monocots showed lower in vitro and in situ digestibilities, fermentation rate, cumulative gas production and extent of degradation than dicot species. The plants were clustered by principal components analysis in two groups: poor-quality grasses and the most digestible dicot species. Chemical composition (neutral detergent fibre and protein) and digestibility were the main influential variables determining the ranking. In conclusion, A. halimus, A. campestris, A. herba-alba and A. gombiformis can be considered of greater nutritional value than the highly fibrous and low digestible grasses (S. pungens, L. spartum and S. tenacissima) that should be considered emergency roughages. (Author) 46 refs.
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Daliakopoulos, Ioannis; Tsanis, Ioannis
2017-04-01
Mitigating the vulnerability of Mediterranean rangelands against degradation is limited by our ability to understand and accurately characterize those impacts in space and time. The Normalized Difference Vegetation Index (NDVI) is a radiometric measure of the photosynthetically active radiation absorbed by green vegetation canopy chlorophyll and is therefore a good surrogate measure of vegetation dynamics. On the other hand, meteorological indices such as the drought assessing Standardised Precipitation Index (SPI) are can be easily estimated from historical and projected datasets at the global scale. This work investigates the potential of driving Random Forest (RF) models with meteorological indices to approximate NDVI-based vegetation dynamics. A sufficiently large number of RF models are trained using random subsets of the dataset as predictors, in a bootstrapping approach to account for the uncertainty introduced by the subset selection. The updated E-OBS-v13.1 dataset of the ENSEMBLES EU FP6 program provides observed monthly meteorological input to estimate SPI over the Mediterranean rangelands. RF models are trained to depict vegetation dynamics using the latest version (3g.v1) of the third generation GIMMS NDVI generated from NOAA's Advanced Very High Resolution Radiometer (AVHRR) sensors. Analysis is conducted for the period 1981-2015 at a gridded spatial resolution of 25 km. Preliminary results demonstrate the potential of machine learning algorithms to effectively mimic the underlying physical relationship of drought and Earth Observation vegetation indices to provide estimates based on precipitation variability.
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A 3-yr study was conducted to comprehensively evaluate Columbia, Suffolk, USMARC-Composite (Composite), and Texel breeds as terminal sires in an extensive rangeland production system. The objective was to estimate breed-of-ram effects on ewe fertility, prolificacy, and dystocia, and sire breed effe...
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relationships between vegetation composition and environmental
African Journals Online (AJOL)
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Borana region, studies on the plant-environment interactions are scanty .... The ordination methods used for the vegetation ..... adaptation, rangeland restoration and also for identifying places ... mangrove forests in Kenya and Sri Lanka. Plant.
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Soils as a Solution: The Potential of Rangelands to Contribute to Climate Change Mitigation
Silver, W. L.; Ryals, R.; DeLonge, M. S.; Owen, J. J.
2015-12-01
The majority of soil-related climate change research has focused on describing the problem - estimating rates of carbon (C) losses and greenhouse gas (GHG) emissions from natural and managed ecosystems. More research is needed to explore potential solutions to climate change through mitigation and adaptation. Here we report on an integrated set of studies aimed at critically evaluating the biogeochemical potential of rangeland soils to help mitigate climate change, while improving the sustainability and productivity of food production systems. We explored direct effects through enhanced net primary production (NPP) and soil C sequestration, and indirect effects through diversion of high emitting sources to lower emitting organic matter dynamics. We used a combination of long- and short-term field experiments, modeling, laboratory assays, life cycle assessment (LCA), and meta-analyses in consultation with a diverse group of stakeholders from both the private and public sectors. We found that organic matter amendments held particularly strong potential. Compost amendments increased soil C storage by 0.5-1.0 Mg C ha-1 y-1 in surface soils over 5 y, and increased NPP and water holding capacity. We measured 1.0 Mg of new C ha-1 y-1 over 3 y. Long-term amendment of cattle manure increased surface soil C by 19.0±7.3 Mg C ha-1 relative to unmanured fields. However, field and modeling experiments suggested that manure amendments lead to large nitrous oxide emissions that eventually eliminated CO2e benefits, whereas compost amendments continued to benefit climate for decades longer. An LCA identified a broader range of climate impacts. When scaled to an area of 25% of California's rangelands, new C sequestered following compost amendments (21 million Mg CO2e) exceeded emissions from cattle (15 million Mg CO2e); diverting organics from waste streams to amendments led to additional GHG savings. In collaboration with our partners, our research contributed to the development of
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The influence of ungulates on non-native plant invasions in forests and rangelands: a review.
Catherine G. Parks; Michael J. Wisdom; John G. Kie
2005-01-01
Herbivory by wild and domestic ungulates can strongly influence vegetation composition and productivity in forest and range ecosystems. However, the role of ungulates as contributors to the establishment and spread of non-native invasive plants is not well known. Ungulates spread seeds through endozoochory (passing through an animal's digestive tract) or...
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J.C. Chambers; J.L. Beck; J.B. Bradford; J. Bybee; S. Campbell; J. Carlson; T.J. Christiansen; K.J. Clause; G. Collins; M.R. Crist; J.B. Dinkins; K.E. Doherty; F. Edwards; S. Espinosa; K.A. Griffin; P. Griffin; J.R. Haas; S.E. Hanser; D.W. Havlina; K.F. Henke; J.D. Hennig; L.A. Joyce; F.M. Kilkenny; S.M. Kulpa; L.L. Kurth; J.D. Maestas; M. Manning; K.E. Mayer; B.A. Mealor; C. McCarthy; M. Pellant; M.A. Perea; K.L. Prentice; D.A. Pyke; L.A. Wiechman; A. Wuenschel
2017-01-01
The Science Framework is intended to link the Department of the Interiorâs Integrated Rangeland Fire Management Strategy with long-term strategic conservation actions in the sagebrush biome. The Science Framework provides a multiscale approach for prioritizing areas for management and determining effective management strategies within the sagebrush biome. The emphasis...
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Pricope, N. G.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.
2014-12-01
Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. We identify regions where significant rainfall decrease from 1979-2011 over the entire continent of Africa couples with significant human population density increase. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that widespread degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using two underutilized MODIS products, we observe significant changes in vegetation patterns and productivity over the last decade all across the East African Horn. We observe significant vegetation browning trends in areas experiencing drying precipitation trends in addition to increasing population pressures. We also found that the drying precipitation trends only partially statistically explain the vegetation browning trends, further indicating that other factors such as population pressures and land use changes are responsible for the observed declining vegetation health. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, indicating potential long-term degradation of rangelands on which approximately 10 million people depend. These findings have serious implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected
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Metternicht, Graciela; Blanco, Paula; del Valle, Hector; Laterra, Pedro; Hardtke, Leonardo; Bouza, Pablo
2015-04-01
Wildlife is part of the Patagonian rangelands sheep farming environment, with the potential of providing extra revenue to livestock owners. As sheep farming became less profitable, farmers and ranchers could focus on sustainable wildlife harvesting. It has been argued that sustainable wildlife harvesting is ecologically one of the most rational forms of land use because of its potential to provide multiple products of high value, while reducing pressure on ecosystems. The guanaco (Lama guanicoe) is the most conspicuous wild ungulate of Patagonia. Guanaco ?bre, meat, pelts and hides are economically valuable and have the potential to be used within the present Patagonian context of production systems. Guanaco populations in South America, including Patagonia, have experienced a sustained decline. Causes for this decline are related to habitat alteration, competition for forage with sheep, and lack of reasonable management plans to develop livelihoods for ranchers. In this study we propose an approach to explicitly determinate optimal stocking rates based on trade-offs between guanaco density and livestock grazing intensity on rangelands. The focus of our research is on finding optimal sheep stocking rates at paddock level, to ensure the highest production outputs while: a) meeting requirements of sustainable conservation of guanacos over their minimum viable population; b) maximizing soil carbon sequestration, and c) minimizing soil erosion. In this way, determination of optimal stocking rate in rangelands becomes a multi-objective optimization problem that can be addressed using a Fuzzy Multi-Objective Linear Programming (MOLP) approach. Basically, this approach converts multi-objective problems into single-objective optimizations, by introducing a set of objective weights. Objectives are represented using fuzzy set theory and fuzzy memberships, enabling each objective function to adopt a value between 0 and 1. Each objective function indicates the satisfaction of
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Evaluating soil moisture and hydraulic conductivity in semi-arid rangeland soils
International Nuclear Information System (INIS)
Whitaker, M.P.L.
1993-01-01
The US DOE's Office of Civilian Radioactive Waste Management (DOE-OCRWM) Fellowship Program supports various disciplines of academic research related to the isolation of radionuclides from the biosphere. The purpose of this paper is to provide an example of a university research application in the specific discipline of hydrology and water resources (a multi-disciplinary field encompassing engineering and the earth sciences), and to discuss how this research pertains to the objectives of the DOE-OCRWM Fellowship Program. The university research application is twofold: One portion focuses on the spatial variability of soil moisture (θ) and the other section compares point measurements with small watershed estimates of hydraulic conductivity (K) in a semi-arid rangeland soil in Arizona. For soil moisture measurements collected over a range of horizontal sampling intervals, no spatial correlation was evident. This outcome is reassuring to computer modelers who have assumed no spatial correlation for soil moisture over smaller scales. In regard to hydraulic conductivity, point measurements differed significantly from small watershed estimates of hydraulic conductivity which were derived from a calibrated and verified rainfall-runoff computer model. The estimates of saturated hydraulic conductivity (Ks) were obtained from previous computer simulations in which measured data was collected in the same research location as the present study
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Ludwig, F.
2001-01-01
Keywords: Rangelands, Semi-arid areas, stable isotopes, Acacia, C 4- grasses, plant nutrients, soil nutrients, soil water, plant water relations
Savanna trees can either increase or decrease the productivity of understorey grasses. Trees reduce grass
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Using long-term datasets to study exotic plant invasions on rangelands in the western United States
Invasions by exotic species are generally described with a logistic growth curve divided into three phases: introduction, expansion and saturation. This model is constructed primarily from regional studies of plant invasions based on historical records and herbarium samples. The goal of this study w...
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Karimpour Reihan, Majid
2010-05-01
Increase of playas, decrease of water quality, soil and plant degradation is one of important problems in recent decays. Notwithstanding increase of playa wetlands- 4 million ha in our country- is perform some investigations about this biome and components and this lack of investigation is made degradation of water, soil, plant potentials and at least desertification. Then, management the biome and planning for sustainable development is very important because of sensitive this environments and has requirement to recognize ecological properties and components, so in this study, try to investigate fasting and latent this regions. At last for potentialization of region for rangeland, water and dry culture use, assessment and classification of region was performed with aim of FAO formula. According to this formula, environmental factors studied and performed grading and classifying. Basis on results, the region is not proper for dry farming and view of water farming and rangeland was settled in 5 and 6 classes. Latest result should be conserving the region. For this act, our introduced 13 halophyte plats with view of investigation of 20 factors. May god will, ganged this regions to good rangelands and forests of dry regions. Key words: Assessment of lands, Hoze Soltane of Qom, environmental factors, FAO, Compatible Plants, Reclamation strategies
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Mahmoudabadi, Ebrahim; Karimi, Alireza; Haghnia, Gholam Hosain; Sepehr, Adel
2017-09-11
Digital soil mapping has been introduced as a viable alternative to the traditional mapping methods due to being fast and cost-effective. The objective of the present study was to investigate the capability of the vegetation features and spectral indices as auxiliary variables in digital soil mapping models to predict soil properties. A region with an area of 1225 ha located in Bajgiran rangelands, Khorasan Razavi province, northeastern Iran, was chosen. A total of 137 sampling sites, each containing 3-5 plots with 10-m interval distance along a transect established based on randomized-systematic method, were investigated. In each plot, plant species names and numbers as well as vegetation cover percentage (VCP) were recorded, and finally one composite soil sample was taken from each transect at each site (137 soil samples in total). Terrain attributes were derived from a digital elevation model, different bands and spectral indices were obtained from the Landsat7 ETM+ images, and vegetation features were calculated in the plots, all of which were used as auxiliary variables to predict soil properties using artificial neural network, gene expression programming, and multivariate linear regression models. According to R 2 RMSE and MBE values, artificial neutral network was obtained as the most accurate soil properties prediction function used in scorpan model. Vegetation features and indices were more effective than remotely sensed data and terrain attributes in predicting soil properties including calcium carbonate equivalent, clay, bulk density, total nitrogen, carbon, sand, silt, and saturated moisture capacity. It was also shown that vegetation indices including NDVI, SAVI, MSAVI, SARVI, RDVI, and DVI were more effective in estimating the majority of soil properties compared to separate bands and even some soil spectral indices.
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A War of Words: Do Conflict Metaphors Affect Beliefs about Managing “Unwanted” Plants?
Directory of Open Access Journals (Sweden)
Cameron G. Nay
2013-03-01
Full Text Available Woody plants have increased in density and extent in rangelands worldwide since the 1800s, and land managers increasingly remove woodland plants in hopes of restoring pre-settlement conditions and/or improved forage for grazing livestock. Because such efforts can be controversial, especially on publicly owned lands, managers often attempt to frame issues in ways they believe can improve public acceptance of proposed actions. Frequently these framing efforts employ conflict metaphors drawn from military or legal lexicons. We surveyed citizens in the Rocky Mountains region, USA, about their beliefs concerning tree-removal as a management strategy. Plants targeted for removal in the region include such iconic tree species as Douglas-fir and ponderosa pine as well as other less-valued species, such as Rocky Mountain juniper, that are common targets for removal nationwide. To test the influence of issue frame on acceptance, recipients were randomly assigned surveys in which the reason for conifer removal was described using one of three terms often employed by invasive biologists and land managers: “invasion”, “expansion”, and “encroachment”. Framing in this instance had little effect on responses. We conclude the use of single-word frames by scientists and managers use to contextualize an issue may not resonate with the public.
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Dalea ornata and D. searlsiae are non-toxic native legumes that have potential for increasing forage production and forage quality of degraded rangelands in the western U.S.A. It is important to characterize the population structures in both species for developing new plant materials through plant ...
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Impact of Prosopis (mesquite) invasion and clearing on vegetation ...
African Journals Online (AJOL)
We evaluated the impact of Prosopis invasion and clearing on vegetation species composition and diversity (alien and indigenous species richness and cover) in Nama-Karoo rangeland on two sheep farms in the Beaufort ... Keywords: invasive plants – exotic, Nama-Karoo, plant community ecology, rehabilitation, semi-arid ...
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Directory of Open Access Journals (Sweden)
Marcelo P Chartier
2010-07-01
work we examine the efficiency of the WEPP model in predicting the hydrological processes and soil erosion in semiarid rangelands of the northeast Chubut Province. Three plant communities along a soil degradation gradient were identified: grass with scattered shrubs (EH, grass-shrubs (EHA, and degraded shrub steppes (EA. In each of these communities simulated rainfall (100 mm h-1 for 30 min was applied on 1 m² (0.6 x 1.67 m plots and total runoff and sediment production were collected. Using the soil surface condition data from each plot, runoff and sediment production were estimated by means of the WEPP model. We found a low efficiency of the WEPP model to predict runoff (Efficiency, E = 0.14 and soil erosion (E = -0.93. The WEPP-estimated runoff and soil losses showed high sensitivity to changes in rainfall and slope parameters and moderate sensitivity to changes in soil cover, texture, soil erodability and effective hydraulic conductivity. The runoff and sediment production estimated by the WEPP model were significantly different among plant communities (p < 0.05. The difference between the estimated and observed mean values varied in the different plant communities: runoff according to the WEPP model was 55.5% greater in the EH and sediment production was 69.6, 62.7 and 17.5% lower, respectively, in the EH, EHA, and EA than the observed values. These results suggest that it is necessary to calibrate the model for local conditions and to incorporate rangeland stratification according to the different soil-vegetation units.
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Rangeland -- plant response to elevated CO2
International Nuclear Information System (INIS)
Owensby, C.E.; Coyne, P.I.; Ham, J.M.; Parton, W.; Rice, C.; Auen, L.M.; Adam, N.
1993-01-01
Plots of a tallgrass prairie ecosystem were exposed to ambient and twice-ambient CO 2 concentrations in open-top chambers and compared to unchambered ambient CO 2 plots during the entire growing season from 1989 through 1992. Relative root production among treatments was estimated using root ingrowth bags which remained in place throughout the growing season. Latent heat flux was simulated with and without water stress. Botanical composition was estimated annuallyin all treatments. Open-top chambers appeared to reduce latent heat flux and increase water use efficiency similar to elevated CO 2 when water stress was not severe, but under severe water stress, chamber effect on water use efficiency was limited. In natural ecosystems with periodic moisture stress, increased water use efficiency under elevated CO 2 apparently would have a greater impact on productivity than photosynthetic pathway. Root ingrowth biomass was greater in 1990 and 1991 on elevated CO 2 plots compared to ambient or chambered-ambient plots. In 1992, there was no difference in root ingrowth biomass among treatments
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Olivas-Salazar, Raquel; Estrada-Angulo, Alfredo; Mellado, Miguel; Aguilar-Caballero, Armando Jacinto; Castro-Pérez, Beatriz Isabel; Gutiérrez-Blanco, Eduardo; Ruiz-Zárate, Fernando
2018-04-01
The objective of this study was to determine the prevalence of gastrointestinal nematode (GIN) infection in goat flocks on semi-arid rangelands of northeastern Mexico (25° N, 350-400 mm annual precipitation). The study included 668 pluriparous goats from 18 herds in five municipalities of Coahuila and Nuevo Leon, Mexico. Five genetic groups were considered (predominance of Boer, Nubian, Alpine, Saanen, and Toggenburg). Fecal samples were taken from the rectum of each animal to determine the number of eggs per gram (EPG) of GIN. The prevalence of flocks with GIN infections was 88.9%. Similar results were observed for the number of goats infected in the flocks. The Alpine breed presented the highest prevalence and highest EPG loads of GIN, whereas Boer and Nubian were the genetic groups with the lowest (P arid zones of Mexico was found a high prevalence of infections with gastrointestinal nematodes. The municipality and the breed of the animals were factors that showed influence on this prevalence and the level of infection of the goats.
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JanaLynn Franke; Brad Geary; Susan E. Meyer
2014-01-01
The genus Fusarium has a wide host range and causes many different forms of plant disease. These include seed rot and seedling blight diseases of cultivated plants. The diseases caused by Fusarium on wild plants are less well-known. In this study, we examined disease development caused by Fusarium sp. n on nondormant seeds of the important rangeland weed Bromus...
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AERO: A Decision Support Tool for Wind Erosion Assessment in Rangelands and Croplands
Galloza, M.; Webb, N.; Herrick, J.
2015-12-01
Wind erosion is a key driver of global land degradation, with on- and off-site impacts on agricultural production, air quality, ecosystem services and climate. Measuring rates of wind erosion and dust emission across land use and land cover types is important for quantifying the impacts and identifying and testing practical management options. This process can be assisted by the application of predictive models, which can be a powerful tool for land management agencies. The Aeolian EROsion (AERO) model, a wind erosion and dust emission model interface provides access by non-expert land managers to a sophisticated wind erosion decision-support tool. AERO incorporates land surface processes and sediment transport equations from existing wind erosion models and was designed for application with available national long-term monitoring datasets (e.g. USDI BLM Assessment, Inventory and Monitoring, USDA NRCS Natural Resources Inventory) and monitoring protocols. Ongoing AERO model calibration and validation are supported by geographically diverse data on wind erosion rates and land surface conditions collected by the new National Wind Erosion Research Network. Here we present the new AERO interface, describe parameterization of the underpinning wind erosion model, and provide a summary of the model applications across agricultural lands and rangelands in the United States.
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Czech Academy of Sciences Publication Activity Database
Šerá, Božena; Válková, D.; Kocianová, E.; Šerý, M.; Feráková, V.; Hodálová, I.
2013-01-01
Roč. 42, č. 2 (2013), s. 449-454 ISSN 0556-3321 Institutional support: RVO:67179843 Keywords : grasslands * biology * plant * flora * rangeland Subject RIV: EH - Ecology, Behaviour Impact factor: 1.207, year: 2013
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Williams, C. J.; Pierson, F. B.; Robichaud, P. R.; Spaeth, K. E.; Hardegree, S. P.; Clark, P. E.; Moffet, C. A.; Al-Hamdan, O. Z.; Boll, J.
2010-12-01
Landscape-scale plant community transitions and altered fire regimes across Great Basin, USA, rangelands have increased the likelihood of post-fire flooding and erosion events. These hazards are particularly concerning for western urban centers along the rangeland urban-wildland interface where natural resources, property, and human life are at risk. Extensive conversion of 4-7 million hectares of Great Basin shrub-steppe to cheatgrass-dominated (Bromus tectorum) grasslands has increased the frequency and size of wildland fires within these ecosystems. Fire frequencies have increased by more than an order of magnitude and occur on 3-10 year intervals across much of the cheatgrass-dominated landscape. Extensive tree (Pinus spp. and Juniperus spp.) encroachment into wooded shrub-steppe has increased heavy fuel loads. Ladder fuels in these ecosystems promote rapidly spreading, high-intensity and severe ground-surface-crown fires. These altered fuel structures across much of the historical Great Basin shrub-steppe have initiated an upsurge in large rangeland wildfires and have increased the spatial and temporal vulnerability of these landscapes to amplified runoff and erosion. Resource and infrastructure damages, and loss of life have been reported due to flooding following recent large-scale burning of western rangelands and dry forests. We present a decade of post-fire rangeland hydrologic research that provides a foundation for conceptual modeling of the hydrologic impacts associated with an increased role of rangeland wildfires. We highlight advancements in predictive tools to address this large-scale phenomenon and discuss vital research voids requiring attention. Our geographic emphasis is the Great Basin Region, however, these concepts likely extend elsewhere given the increased role of fire in many geographic regions and across rangeland-to-forest ecotones in the western United States.
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Plant Guide: Arrowleaf balsamroot (Balsamorhiza sagittata [Pursh] Nutt.)
Derek Tilley; Loren St. John; Nancy Shaw
2012-01-01
A wide variety of wildlife utilizes arrowleaf balsamroot. Deer, elk, bighorn sheep and pronghorn eat the leaves, stems and flowers. Arrowleaf balsamroot can be used to improve spring and summer forage in open rangelands. Ogle and Brazee (2009) list arrowleaf balsamroot as desired forage for cattle, sheep, elk, and pronghorn in spring and summer. Young tissues of...
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Irrigation requirements for seed production of five Lomatium species in a semiarid environment
Clinton C. Shock; Erik B. G. Feibert; Alicia Rivera; Lamont D. Saunders; Nancy Shaw; Francis F. Kilkenny
2016-01-01
Seeds of native plants are needed for rangeland restoration in the Intermountain West. Many of these plants are rarely cultivated and relatively little is known about the cultural practices required for their seed production. Irrigation trials were conducted for five perennial Lomatium species over multiple years. Lomatium species grown at the Oregon State University...
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Using a dynamic model to assess trends in land degradation by water erosion in Spanish Rangelands
Ibáñez, Javier; Francisco Lavado-Contador, Joaquín; Schnabel, Susanne; Pulido-Fernández, Manuel; Martínez Valderrama, Jaime
2014-05-01
This work presents a model aimed at evaluating land degradation by water erosion in dehesas and montados of the Iberian Peninsula, that constitute valuable rangelands in the area. A multidisciplinary dynamic model was built including weather, biophysical and economic variables that reflect the main causes and processes affecting sheet erosion on hillsides of the study areas. The model has two main and two derived purposes: Purpose 1: Assessing the risk of degradation that a land-use system is running. Derived purpose 1: Early warning about land-use systems that are particularly threatened by degradation. Purpose 2: Assessing the degree to which different factors would hasten degradation if they changed from the typical values they show at present. Derived purpose 2: Evaluating the role of human activities on degradation. Model variables and parameters have been calibrated for a typical open woodland rangeland (dehesa or montado) defined along 22 working units selected from 10 representative farms and distributed throughout the Spanish region of Extremadura. The model is the basis for a straightforward assessment methodology which is summarized by the three following points: i) The risk of losing a given amount of soil before a given number of years was specifically estimated as the percentage of 1000 simulations where such a loss occurs, being the simulations run under randomly-generated scenarios of rainfall amount and intensity and meat and supplemental feed market prices; ii) Statistics about the length of time that a given amount of soil takes to be lost were calculated over 1000 stochastic simulations run until year 1000, thereby ensuring that such amount of soil has been lost in all of the simulations, i.e. the total risk is 100%; iii) Exogenous factors potentially affecting degradation, mainly climatic and economic, were ranked in order of importance by means of a sensitivity analysis. Particularly remarkable in terms of model performance is the major role
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A common-garden study of resource-island effects on a native and an exotic, annual grass after fire
Hoover, Amber N.; Germino, Matthew J.
2012-01-01
Plant-soil variation related to perennial-plant resource islands (coppices) interspersed with relatively bare interspaces is a major source of heterogeneity in desert rangelands. Our objective was to determine how native and exotic grasses vary on coppice mounds and interspaces (microsites) in unburned and burned sites and underlying factors that contribute to the variation in sagebrush-steppe rangelands of the Idaho National Lab, where interspaces typically have abiotic crusts. We asked how the exotic cheatgrass (Bromus tectorum L.) and native bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Löve) were distributed among the microsites and measured their abundances in three replicate wildfires and nearby unburned areas. We conducted a common-garden study in which soil cores from each burned microsite type were planted with seed of either species to determine microsite effects on establishment and growth of native and exotic grasses. We assessed soil physical properties in the common-garden study to determine the intrinsic properties of each microsite surface and the retention of microsite soil differences following transfer of soils to the garden, to plant growth, and to wetting/drying cycles. In the field study, only bluebunch wheatgrass density was greater on coppice mounds than interspaces, in both unburned and burned areas. In the common-garden experiment, there were microsite differences in soil physical properties, particularly in crust hardness and its relationship to moisture, but soil properties were unaffected by plant growth. Also in the experiment, both species had equal densities yet greater dry mass production on coppice-mound soils compared to interspace soils, suggesting microsite differences in growth but not establishment (likely related to crust weakening resulting from watering). Coppice-interspace patterning and specifically native-herb recovery on coppices is likely important for postfire resistance of this rangeland to cheatgrass.
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Dawson, Terence J; McTavish, Kirsten J; Munn, Adam J; Holloway, Joanne
2006-01-01
The Eastern Grey Kangaroo (Macropus giganteus) occurs mostly in the wetter regions of eastern Australia. However, in the past 30-40 years it has moved into more arid regions (rainfall Kangaroo (Macropus rufus). An increased access to water (supplied for domestic stock) may explain this range extension, but changes in the availability of preferred feed could also be involved. The water use, drinking patterns and thermoregulatory behaviour of these two species of kangaroo have been examined in a semi-free range study, during summer at an arid rangeland site. Foraging was largely nocturnal in both species and during the day they behaved to reduce heat loads. This was especially so for M. giganteus, which showed greater shade seeking. However, it still used more water (72 +/- 2.6 mL kg(-1) day(-1), mean +/- SE) than M. rufus (56 +/- 7.6 mL kg(-1) day(-1)) and drank twice as frequently. Although M. giganteus produced a less concentrated urine (1422 +/- 36 mosmol kg(-1)) than M. rufus (1843 +/- 28 mosmol kg(-1)), kidney physiology did not explain all of the differences in water metabolism between the species. Water from the feed and faecal water retention also appear to be involved. Broadly, a better access to reliable water and the utilisation of mesic microhabitats has enabled M. giganteus to make inroads into the changing rangelands of eastern Australia. However, changes in the vegetation, due to stock grazing, have also favoured M. giganteus, which is a grass eating specialist.
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Influencing adaptation processes on the Australian rangelands for social and ecological resilience
Directory of Open Access Journals (Sweden)
Nadine A. Marshall
2014-06-01
Full Text Available Resource users require the capacity to cope and adapt to climate changes affecting resource condition if they, and their industries, are to remain viable. Understanding individual-scale responses to a changing climate will be an important component of designing well-targeted, broad-scale strategies and policies. Because of the interdependencies between people and ecosystems, understanding and supporting resilience of resource-dependent people may be as important an aspect of effective resource management as managing the resilience of ecological components. We refer to the northern Australian rangelands as an example of a system that is particularly vulnerable to the impacts of climate change and look for ways to enhance the resilience of the system. Vulnerability of the social system comprises elements of adaptive capacity and sensitivity to change (resource dependency as well as exposure, which is not examined here. We assessed the adaptive capacity of 240 cattle producers, using four established dimensions, and investigated the association between adaptive capacity and climate sensitivity (or resource dependency as measured through 14 established dimensions. We found that occupational identity, employability, networks, strategic approach, environmental awareness, dynamic resource use, and use of technology were all positively correlated with at least one dimension of adaptive capacity and that place attachment was negatively correlated with adaptive capacity. These results suggest that adaptation processes could be influenced by focusing on adaptive capacity and these aspects of climate sensitivity. Managing the resilience of individuals is critical to processes of adaptation at higher levels and needs greater attention if adaptation processes are to be shaped and influenced.
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Lankester, F; Davis, A
2016-11-01
The relationship between pastoralists, their livestock, wildlife and the rangelands of East Africa is multi-directional, complex and long-standing. The tumultuous events of the past century, however, have rewritten the nature of this relationship, reshaping the landscapes that were created, and relied upon, by both pastoralists and wildlife. Presently, much of the interaction between wildlife and pastoralists takes place in and around protected areas, the most contentious occurring in pastoral lands surrounding national parks. In conservation terminology these areas are called buffer zones. In the past century buffer zones have been shaped by, and contributed to, restrictive conservation policies, expropriation of land, efforts to include communities in conservation, both positive and negative wildlife/livestock interactions, and political tensions. In this review paper, the authors outline the history that shaped the current relationship between pastoralists, livestock and wildlife in buffer zones in East Africa and highlight some of the broader issues that pastoralists (and pastoralism as an effective livelihood strategy) now face. Finally, they consider some of the sustainable and equitable practices that could be implemented to improve livelihoods and benefit wildlife and pastoralism alike.
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Directory of Open Access Journals (Sweden)
Peter N Macharia
2010-11-01
Full Text Available A two phase study was carried out from 2002 to 2005 in the semi-arid rangelands of Kajiado District, Kenya to determine the effect of introduced forage legumes on soil fertility improvement of natural pastures. During legume evaluation phase, Neonotonia wightii (Glycine, Macroptilium atropurpureum (Siratro, Lablab purpureus cv. Rongai (Dolichos, Mucuna pruriens (Velvet bean and Stylosanthes scabra var. Seca (Stylo were screened for adaptability and growth performance under the semi-arid conditions for two years. Results of soil analysis showed there were significant increases in soil pH (4.92 to 5.36, organic carbon (1.17 to 2.57% , nitrogen (0.17 to 0.22% and potassium (1.23 to 1.68 me% probably due to the large amounts of organic residues produced by the legumes (particularly Glycine, Siratro and Stylo which are perennials. The calcium content decreased significantly from 7.97 to 4.50 me% (which was attributed to plant uptake while the decrease of phosphorus was not significant. During the second phase of study for 1½ years Glycine, Siratro and Stylo were integrated into natural pastures. The results showed that only the soil pH significantly increased from 5.23 to 5.31 while all the other nutrients decreased results, which were attributed to production of less organic residues by the legumes compared to the residues produced during the legume evaluation phase. The study concluded that Glycine, Siratro and Stylo were capable of improving the soil fertility of semi-arid natural pastures only if the respective dry matter production was 10.31, 7.81 and 3.52 tha-1, amounts which were able to produce large amounts of organic residues. Â
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Research Note Effects of previous cultivation on regeneration of ...
African Journals Online (AJOL)
We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...
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Increasing atmospheric [CO2] and temperature are expected to affect the productivity, species composition, biogeochemistry, and therefore the quantity and quality of forage available to herbivores in rangeland ecosystems. Both elevated CO2 (eCO2) and warming affect plant tissue chemistry through mul...
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Phenology of exotic invasive weeds associated with downy brome
The exotic and highly invasive annual grass downy brome (Bromus tectorum) has invaded millions of hectares of rangelands throughout the Intermountain West. Downy brome increases the chance, rate, season and spread of wildfires, resulting in the destruction of native plant communities and the wildli...
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Downy brome control and impacts on perennial grass abundance: a systematic review spanning 64 years
Given the high cost of restoration and the underlying assumption that reducing annual grass abundance is a necessary precursor to rangeland restoration in the Intermountain West, USA, we sought to identify limitations and strengths of annual grass and woody plant reduction methods and refine future ...
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Increasing atmospheric [CO2] and temperature are expected to affect the productivity, species composition, biogeochemistry, and therefore the quantity and quality of forage available to herbivores in rangeland ecosystems. Both elevated CO2 (eCO2) and warming affect plant tissue chemistry through mul...
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Landau, S Y; Dvash, L; Roudman, M; Muklada, H; Barkai, D; Yehuda, Y; Ungar, E D
2016-02-01
Rapid assessment of the nutritional quality of diets ingested by grazing animals is pivotal for successful cow-calf management in east Mediterranean rangelands, which receive unpredictable rainfall and are subject to hot-spells. Clipped vegetation samples are seldom representative of diets consumed, as cows locate and graze selectively. In contrast, faeces are easily sampled and their near-IR spectra contain information about nutrients and their utilization. However, a pre-requisite for successful faecal near-infrared reflectance spectroscopy (FNIRS) is that the calibration database encompass the spectral variability of samples to be analyzed. Using confined beef cows in Northern and Southern Israel, we calibrated prediction equations based on individual pairs of known dietary attributes and the NIR spectra of associated faeces (n=125). Diets were composed of fresh-cut green fodder of monocots (wheat and barley), dicots (safflower and garden pea) and natural pasture collected at various phenological states over 2 consecutive years, and, optionally, supplements of barley grain and dried poultry litter. A total of 48 additional pairs of faeces and diets sourced from cows fed six complete mixed rations covering a wide range of energy and CP concentrations. Precision (linearity of calibration, R2cal, and of cross-validation, R2cv) and accuracy (standard error of cross-validation, SEcv) were criteria for calibration quality. The calibrations for dietary ash, CP, NDF and in vitro dry matter digestibility yielded R2cal values >0.87, R2cv of 0.81 to 0.89 and SEcv values of 16, 13, 39 and 31 g/kg dry matter, respectively. Equations for nutrient intake were of low quality, with the exception of CP. Evaluation of FNIRS predictions was carried out with grazing animals supplemented or not with poultry litter, and implementation of the method in one herd over 2 years is presented. The potential usefulness of equations was also established by calculating the Mahalanobis (H
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Directory of Open Access Journals (Sweden)
José Fernando Vázquez-Armijo
2010-10-01
Full Text Available The effect of season (rainy: RS, and dry: DS and reproductive status on copper (Cu and zinc (Zn concentrations in blood serum of crossbred goats (BW= 36.01 ± 1.59 kg were studied under semiarid rangeland conditions in Southern Mexico State. Blood samples from 80 crossbred goats were taken each season (RS and DS. The goats were clustered into 10 different groups considering their reproductive status. Concentrations of Cu and Zn in serum were assayed using atomic absorption. Data were analyzed using a general linear model procedure for a completely randomized design and differences among means were examined using a Tukey test. Blood serum concentrations of Cu and Zn were affected by reproductive status and season (P
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Calibrating the Truax Rough Rider seed drill for restoration plantings
Loren St. John; Brent Cornforth; Boyd Simonson; Dan Ogle; Derek Tilley
2008-01-01
The purpose of this technical note is to provide a step-by-step approach to calibrating the Truax Rough Rider range drill, a relatively new, state-of-the-art rangeland drill. To achieve the desired outcome of a seeding project, an important step following proper weed control and seedbed preparation is the calibration of the seeding equipment to ensure the recommended...
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DEFF Research Database (Denmark)
Krenz, Juliane; Greenwood, Philip; Kuhn, Brigitte
The semi-arid rangelands of the Great Karoo region in South Africa, which are nowadays characterized by badlands on the foot slopes of upland areas and complex gully systems in valley bottoms, have experienced a number of environmental changes. With the settlement of European farmers in the late ......th century agricultural activities increased, leading to overgrazing which probably acted as a trigger to land degradation. As a consequence of higher water demands and shifting rainfall patterns, many dams and small reservoirs have been constructed to provide drinking water for cattle...... or to facilitate irrigation during dry periods. Most of these dams are now filled with sediment and many have become breached, revealing sediment archives that can be used to analyse land use changes as well as carbon erosion and deposition during the last ca. 100 years. In this ongoing project, a combination...
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Increased wildfires in the western U.S. are due to the cyclic accumulation and burning of invasive annual plants such as cheatgrass (Bromus tectorum) and red brome (B. rubens), which reduces native rangeland species and results in servere economic losses and land degradation. Fire was not prevalent...
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Increased wildfires in the western U.S. are due to the cyclic accumulation and burning of invasive annual plants such as cheatgrass (Bromus tectorum) and red brome (B. rubens), which reduces native rangeland species and results in severe economic losses and land degradation. Fire was not prevalent ...
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Spatial variation in seed bank dynamics of two annual brome species in the northern Great Plains
Annual bromes decrease forage production in northern central plains rangelands of North America. Early life history stages are when plants are most failure-prone, yet studying death post-germination and prior to emergence is difficult. In seed bank collections conducted over the course of two growin...
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Risk assessment and implications of common crupina rust disease for biological control
Common crupina is listed as a Federal noxious weed infesting rangelands and pastures in the states of Idaho, Washington, Oregon, and California. Because there is no practical control measure for this plant, and considering its potential to spread extensively at least within the region, an evaluatio...
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Survey of Beaver-related Restoration Practices in Rangeland Streams of the Western USA
Pilliod, David S.; Rohde, Ashley T.; Charnley, Susan; Davee, Rachael R.; Dunham, Jason B.; Gosnell, Hannah; Grant, Gordon E.; Hausner, Mark B.; Huntington, Justin L.; Nash, Caroline
2018-01-01
Poor condition of many streams and concerns about future droughts in the arid and semi-arid western USA have motivated novel restoration strategies aimed at accelerating recovery and increasing water resources. Translocation of beavers into formerly occupied habitats, restoration activities encouraging beaver recolonization, and instream structures mimicking the effects of beaver dams are restoration alternatives that have recently gained popularity because of their potential socioeconomic and ecological benefits. However, beaver dams and dam-like structures also harbor a history of social conflict. Hence, we identified a need to assess the use of beaver-related restoration projects in western rangelands to increase awareness and accountability, and identify gaps in scientific knowledge. We inventoried 97 projects implemented by 32 organizations, most in the last 10 years. We found that beaver-related stream restoration projects undertaken mostly involved the relocation of nuisance beavers. The most common goal was to store water, either with beaver dams or artificial structures. Beavers were often moved without regard to genetics, disease, or potential conflicts with nearby landowners. Few projects included post-implementation monitoring or planned for longer term issues, such as what happens when beavers abandon a site or when beaver dams or structures breach. Human dimensions were rarely considered and water rights and other issues were mostly unresolved or addressed through ad-hoc agreements. We conclude that the practice and implementation of beaver-related restoration has outpaced research on its efficacy and best practices. Further scientific research is necessary, especially research that informs the establishment of clear guidelines for best practices.
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Survey of beaver-related restoration practices in rangeland streams of the western USA
Pilliod, David S.; Rohde, Ashley T.; Charnley, Susan; Davee, Rachael R; Dunham, Jason B.; Gosnell, Hannah; Grant, Gordon E.; Hausner, Mark B.; Huntington, Justin L.; Nash, Caroline
2018-01-01
Poor condition of many streams and concerns about future droughts in the arid and semi-arid western USA have motivated novel restoration strategies aimed at accelerating recovery and increasing water resources. Translocation of beavers into formerly occupied habitats, restoration activities encouraging beaver recolonization, and instream structures mimicking the effects of beaver dams are restoration alternatives that have recently gained popularity because of their potential socioeconomic and ecological benefits. However, beaver dams and dam-like structures also harbor a history of social conflict. Hence, we identified a need to assess the use of beaver-related restoration projects in western rangelands to increase awareness and accountability, and identify gaps in scientific knowledge. We inventoried 97 projects implemented by 32 organizations, most in the last 10 years. We found that beaver-related stream restoration projects undertaken mostly involved the relocation of nuisance beavers. The most common goal was to store water, either with beaver dams or artificial structures. Beavers were often moved without regard to genetics, disease, or potential conflicts with nearby landowners. Few projects included post-implementation monitoring or planned for longer term issues, such as what happens when beavers abandon a site or when beaver dams or structures breach. Human dimensions were rarely considered and water rights and other issues were mostly unresolved or addressed through ad-hoc agreements. We conclude that the practice and implementation of beaver-related restoration has outpaced research on its efficacy and best practices. Further scientific research is necessary, especially research that informs the establishment of clear guidelines for best practices.
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Inacessible Andean sites reveal land-use induced stabilisation of soil organic carbon
Heitkamp, Felix; Maqsood, Shafique; Sylvester, Steven; Kessler, Michael; Jungkunst, Hermann
2015-04-01
these findings were a high proportion of complexed SOC in rangeland soils (25 to 36 vs. 59% of SOC were extractable with Na-pyrophosphate in pristine and rangeland soils, respectively). Moreover, less C was associated with the light fraction (plant-soil) were lower in all density-size fractions and even negative in the light fraction of rangeland soils, meaning that these were more depleted or less enriched with 13C relative to vegetation. This could indicate stabilisation of old C derived from former pristine vegetation (having a lower 13C signature), presence of pyrogenic carbon or specific stabilisation of depleted compounds. Overall, our the approach of using large, inaccessible sites as reference for continuously used sites revealed that grazing management had tremendous effects on the partitioning of SOC among different fractions, but not on the total stocks. Since SOC in rangeland soils was more effectively stabilised, reactions to environmental changes should be slower and SOC in pristine soils is likely to react more sensitive.
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Meyer, Hanna; Authmann, Christian; Dreber, Niels; Hess, Bastian; Kellner, Klaus; Morgenthal, Theunis; Nauss, Thomas; Seeger, Bernhard; Tsvuura, Zivanai; Wiegand, Kerstin
2017-04-01
Bush encroachment is a syndrome of land degradation that occurs in many savannas including those of southern Africa. The increase in density, cover or biomass of woody vegetation often has negative effects on a range of ecosystem functions and services, which are hardly reversible. However, despite its importance, neither the causes of bush encroachment, nor the consequences of different resource management strategies to combat or mitigate related shifts in savanna states are fully understood. The project "IDESSA" (An Integrative Decision Support System for Sustainable Rangeland Management in Southern African Savannas) aims to improve the understanding of the complex interplays between land use, climate patterns and vegetation dynamics and to implement an integrative monitoring and decision-support system for the sustainable management of different savanna types. For this purpose, IDESSA follows an innovative approach that integrates local knowledge, botanical surveys, remote-sensing and machine-learning based time-series of atmospheric and land-cover dynamics, spatially explicit simulation modeling and analytical database management. The integration of the heterogeneous data will be implemented in a user oriented database infrastructure and scientific workflow system. Accessible via web-based interfaces, this database and analysis system will allow scientists to manage and analyze monitoring data and scenario computations, as well as allow stakeholders (e. g. land users, policy makers) to retrieve current ecosystem information and seasonal outlooks. We present the concept of the project and show preliminary results of the realization steps towards the integrative savanna management and decision-support system.
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Redmond, Miranda D; Zelikova, Tamara J; Barger, Nichole N
2014-11-01
National fuel-reduction programs aim to reduce the risk of wildland fires to human communities and to restore forest and rangeland ecosystems to resemble their historical structure, function, and diversity. There are a number of factors, such as seed bank dynamics, post-treatment climate, and herbivory, which determine whether this latter goal may be achieved. Here, we examine the short-term (2 years) vegetation response to fuel-reduction treatments (mechanical mastication, broadcast burn, and pile burn) and seeding of native grasses on understory vegetation in an upland piñon-juniper woodland in southeast Utah. We also examine how wildlife herbivory affects the success of fuel-reduction treatments. Herbaceous cover increased in response to fuel-reduction treatments in all seeded treatments, with the broadcast burn and mastication having greater increases (234 and 160 %, respectively) in herbaceous cover than the pile burn (32 %). In the absence of seeding, herbaceous cover only increased in the broadcast burn (32 %). Notably, fuel-reduction treatments, but not seeding, strongly affected herbaceous plant composition. All fuel-reduction treatments increased the relative density of invasive species, especially in the broadcast burn, which shifted the plant community composition from one dominated by perennial graminoids to one dominated by annual forbs. Herbivory by wildlife reduced understory plant cover by over 40 % and altered plant community composition. If the primary management goal is to enhance understory cover while promoting native species abundance, our study suggests that mastication may be the most effective treatment strategy in these upland piñon-juniper woodlands. Seed applications and wildlife exclosures further enhanced herbaceous cover following fuel-reduction treatments.
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Phenology-based, remote sensing of post-burn disturbance windows in rangelands
Sankeya, Joel B.; Wallace, Cynthia S.A.; Ravi, Sujith
2013-01-01
Wildland fire activity has increased in many parts of the world in recent decades. Ecological disturbance by fire can accelerate ecosystem degradation processes such as erosion due to combustion of vegetation that otherwise provides protective cover to the soil surface. This study employed a novel ecological indicator based on remote sensing of vegetation greenness dynamics (phenology) to estimate variability in the window of time between fire and the reemergence of green vegetation. The indicator was applied as a proxy for short-term, post-fire disturbance windows in rangelands; where a disturbance window is defined as the time required for an ecological or geomorphic process that is altered to return to pre-disturbance levels. We examined variability in the indicator determined for time series of MODIS and AVHRR NDVI remote sensing data for a database of ∼100 historical wildland fires, with associated post-fire reseeding treatments, that burned 1990–2003 in cold desert shrub steppe of the Great Basin and Columbia Plateau of the western USA. The indicator-based estimates of disturbance window length were examined relative to the day of the year that fires burned and seeding treatments to consider effects of contemporary variability in fire regime and management activities in this environment. A key finding was that contemporary changes of increased length of the annual fire season could have indirect effects on ecosystem degradation, as early season fires appeared to result in longer time that soils remained relatively bare of the protective cover of vegetation after fires. Also important was that reemergence of vegetation did not occur more quickly after fire in sites treated with post-fire seeding, which is a strategy commonly employed to accelerate post-fire vegetation recovery and stabilize soil. Future work with the indicator could examine other ecological factors that are dynamic in space and time following disturbance – such as nutrient cycling
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Spatially explicit rangeland erosion monitoring using high-resolution digital aerial imagery
Gillan, Jeffrey K.; Karl, Jason W.; Barger, Nichole N.; Elaksher, Ahmed; Duniway, Michael C.
2016-01-01
Nearly all of the ecosystem services supported by rangelands, including production of livestock forage, carbon sequestration, and provisioning of clean water, are negatively impacted by soil erosion. Accordingly, monitoring the severity, spatial extent, and rate of soil erosion is essential for long-term sustainable management. Traditional field-based methods of monitoring erosion (sediment traps, erosion pins, and bridges) can be labor intensive and therefore are generally limited in spatial intensity and/or extent. There is a growing effort to monitor natural resources at broad scales, which is driving the need for new soil erosion monitoring tools. One remote-sensing technique that can be used to monitor soil movement is a time series of digital elevation models (DEMs) created using aerial photogrammetry methods. By geographically coregistering the DEMs and subtracting one surface from the other, an estimate of soil elevation change can be created. Such analysis enables spatially explicit quantification and visualization of net soil movement including erosion, deposition, and redistribution. We constructed DEMs (12-cm ground sampling distance) on the basis of aerial photography immediately before and 1 year after a vegetation removal treatment on a 31-ha Piñon-Juniper woodland in southeastern Utah to evaluate the use of aerial photography in detecting soil surface change. On average, we were able to detect surface elevation change of ± 8−9cm and greater, which was sufficient for the large amount of soil movement exhibited on the study area. Detecting more subtle soil erosion could be achieved using the same technique with higher-resolution imagery from lower-flying aircraft such as unmanned aerial vehicles. DEM differencing and process-focused field methods provided complementary information and a more complete assessment of soil loss and movement than any single technique alone. Photogrammetric DEM differencing could be used as a technique to
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Maria L. Sonett
1999-01-01
Integrated surface management techniques for pipeline construction through arid and semi-arid rangeland ecosystems are presented in a case history of a 412-mile pipeline construction project in New Mexico. Planning, implementation and monitoring for restoration of surface hydrology, soil stabilization, soil cover, and plant species succession are discussed. Planning...
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2010-06-11
...The USDA, Forest Service, will prepare an environmental impact statement (EIS) analyzing the management of rangeland vegetation resources, which includes livestock grazing, on the National Forest System (NFS) lands within the Oglala Geographic Area (OGA) of the Oglala National Grassland on the Pine Ridge Ranger District and the West Geographic Area (WGA) of the Buffalo Gap National Grassland on the Fall River Ranger District of the Nebraska National Forest (Analysis Area) areas as mapped by the 2001 Nebraska National Forest Revised Land and Resource Management Plan (Forest Plan). A Notice of Intent (NOI) for this project was published February 22, 2008 (73 No. 36 FR 9760- 9762). More than six months have elapsed since the projected draft environmental impact statement (DEIS) date in that original NOI. This revised NOI is being issued to update the project schedule. There will be a record of decision (ROD) for each geographic area. Proposed management actions would be implemented beginning in the year 2012. The agency gives notice of the full environmental analysis and decision-making process that will occur on the proposal so interested and affected people may become aware of how they may participate in the process and contribute to the final decision.
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Larreguy, C; Carrera, A L; Bertiller, M B
2017-09-01
The objective of this study was to estimate the size and chemical quality of the total organic C stock and its partition between above-belowground plant parts and soil at sites with different plant cover induced by sheep grazing in the arid Patagonian Monte. This study was conducted at six representative sites with increasing signs of canopy disturbance attributed to grazing pressure. We used faeces density as a proxy of grazing pressure at each site. We assessed the total plant cover, shrub and perennial grass cover, total standing aboveground biomass (AGB), litter mass and belowground biomass (BGB) at each site. We further estimated the content of organic C, lignin and soluble phenols in plant compartments and the content of organic C, organic C in humic substances (recalcitrant C) and water soluble C (labile C) in soil at each site. Total plant cover was significantly related to grazing pressure. Standing AGB and litter mass decreased with increasing canopy disturbance while BGB did not vary across sites. Total organic C stock and the organic C stock in standing AGB increased with increasing total plant, shrub, and perennial grass cover. The organic C stock in litter mass increased with increasing total plant and shrub cover, while the organic C stock in BGB did not vary across sites. Lignin content in plant compartments increased with increasing total and shrub cover, while soluble phenols content did not change across sites. The organic C stock and the water soluble C content in soil were positively associated with perennial grass cover. Changes in total plant cover induced by grazing pressure negatively affected the size of the total organic C stock, having minor impact on the size of belowground than aboveground components. The reduction of perennial grass cover was reflected in decreasing chemical quality of the organic C stock in soil. Accordingly, plant managerial strategies should not only be focused on the amount of organic C sequestered but also on the
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Paul (tech. ed.) Keller
2004-01-01
Fire management, and forest and rangeland fuels management, over the past century have altered the wildland fire situation dramatically, thus also altering the institutional approach to how to deal with the changing landscape. Also, climate change, extended drought, increased insect and disease outbreaks, and invasions of exotic plant species have added complications...
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C. M. Waters; N. L. Shaw
2003-01-01
Globally, an increased desire to restore, rehabilitate or revegetate with native plants represents a shift toward more ecologically focused restoration goals. In the Australian rangelands, an increasing need to address revegetation is not being matched by an availability of seed material. This contrasts with the United States where a well-structured native seed...
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Soil erosion studies in buffelgrass pastures
Diego Valdez-Zamudio; D. Phillip Guertin
2000-01-01
The introduction of exotic grasses in native rangelands to increase the production of forage has been a good alternative for the cattle industry in North America. Different studies have demonstrated that buffelgrass (Cenchrus ciliaris L.), a plant introduced from Africa, increases the annual green forage production approximately three times in comparison to production...
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The ability of winter grazing to reduce wildfire size, intensity ...
A recent study by Davies et al. sought to test whether winter grazing could reduce wildfire size, fire behavior metrics, and fire-induced plant mortality in shrub-grasslands. The authors concluded that ungrazed rangelands may experience more fire-induced mortality of native perennial bunchgrasses. The authors also presented several statements regarding the benefits of winter grazing on post-fire plant community responses. However, this commentary will show that the study by Davies et al. has underlying methodological flaws, lacks data necessary to support their conclusions, and does not provide an accurate discussion on the effect of grazing on rangeland ecosystems. Importantly, Davies et al. presented no data on the post-fire mortality of the perennial bunchgrasses or on the changes in plant community composition following their experimental fires. Rather, Davies et al. inferred these conclusions based off their observed fire behavior metrics of maximum temperature and a term described as the “heat load”. However, neither metric is appropriate for elucidating the heat flux impacts on plants. This lack of post-fire data, several methodological flaws, and the use of inadequate metrics describing heat cast doubts on the authors’ ability to support their stated conclusions. This article is a commentary highlights the scientific shortcomings in a forthcoming paper by Davies et al. in the International Journal of Wildland Fire. The study has methodological flaw
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Decision Making in Rangelands: An Integrated Modeling Approach to Resilience and Change
Galvin, K. A.; Ojima, D. S.; Boone, R. B.
2007-12-01
Rangelands comprise approximately 25% of the earth's surface and these landscapes support more than 20 million people and most of the world's charismatic megafauna. Most of the people who live in these regions of the world herd domestic livestock and some do limited cultivation so they are dependent directly on the environment for their livelihoods. But change is rapidly changing the environments upon which these people depend through such factors as population pressures, land use and land tenure changes, climate variability, and policy changes which fragment their resources and thus their ability to earn a living. How can we understand change in this linked human-environment system? The study of complex biophysical and human systems can be greatly assisted by appropriate simulation models that integrate what is known about ecological and human decision-making processes. We have developed an integrated modeling system for Kajiado, Kenya where land use management decisions have implications for economics and the ecosystem. In this paper we look at how land use decisions, that is, livestock movement patterns have implications for societal economics and ecosystem services. Research that focuses on local behavior is important because it is at that level where fundamental decisions are made regarding events like extreme climate and changes such as land tenure policy and it is here where resilience is manifested. The notion that broad recommendation domains can be identified for a broad set of people and large regions coping with change is becoming increasingly hard to trust given the spatial and temporal heterogeneity of the systems we are looking at, and the complexity of the world we now live in. Why is this important? The only way the research community is going to make great progress in attaining objectives that do confer resilience (on social and ecological systems) is through much better targeting ability, a large part of which seem to be intimately entwined with
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A checklist of the flora of Shanjan protected area, East Azerbaijan ...
African Journals Online (AJOL)
The flora of protected Shanjan rangeland in Shabestar district, Azerbaijan Province, NW Iran was studied using a 1 m x 1 m quadrate in spring and summer 2011. The climate of this area is cold and dry. In this area 94 plant species belonging to 25 families were identified as constituting the major part of the vegetation.
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Welch, Kevin D; Green, Benedict T; Gardner, Dale R; Stonecipher, Clinton A; Pfister, James A; Cook, Daniel
2016-01-12
In many rangeland settings, there is more than one potential poisonous plant. Two poisonous plants that are often found growing simultaneously in the same location in North American rangelands are death camas (Zigadenus spp.) and low larkspur (Delphinium spp.). The objective of this study was to determine if co-administration of death camas would exacerbate the toxicity of low larkspur in cattle. Cattle dosed with 2.0 g of death camas/kg BW showed slight frothing and lethargy, whereas cattle dosed with both death camas and low larkspur showed increased clinical signs of poisoning. Although qualitative differences in clinical signs of intoxication in cattle co-treated with death camas and low larkspur were observed, there were not any significant quantitative differences in heart rate or exercise-induced muscle fatigue. Co-treatment with death camas and low larkspur did not affect the serum zygacine kinetics, however, there was a difference in the larkspur alkaloid kinetics in the co-exposure group. Overall, the results from this study suggest that co-exposure to death camas and low larkspur is not significantly more toxic to cattle than exposure to the plants individually. The results from this study increase our knowledge and understanding regarding the acute toxicity of death camas and low larkspur in cattle.
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International Nuclear Information System (INIS)
Inoue, Y.; Moran, M.S.; Pinter, P.J.Jr.
1994-01-01
A new concept for estimating potential and actual values of daily transpiration rate of vegetation canopies is presented along with results of an initial test. The method is based on a physical foundation of spectral radiation balance for a vegetation canopy, the key inputs to the model being the remotely sensed spectral reflectance and the surface temperature of the plant canopy. The radiation interception or absorptance is estimated more directly from remotely sensed spectral data than it is from the leaf area index. The potential daily transpiration is defined as a linear function of the absorbed solar radiation, which can be estimated using a linear relationship between the fraction absorptance of solar radiation and the remotely sensed Soil Adjusted Vegetation Index for the canopy. The actual daily transpiration rate is estimated by combining this concept with the Jackson-Idso Crop Water Stress Index, which also can be calculated from remotely sensed plant leaf temperatures measured by infrared thermometry. An initial demonstration with data sets from an alfalfa crop and a rangeland suggests that the method may give reasonable estimates of potential and actual values of daily transpiration rate over diverse vegetation area based on simple remote sensing measurements and basic meteorological parameters
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Inbreeding, Genetic Variation, and Invasiveness: The Strange Case of Bromus tectorum
Susan E. Meyer; Elizabeth A. Leger
2010-01-01
Cheatgrass (Bromus tectorum, downy brome) is arguably the most common plant in the western United States, dominating literally millions of acres of degraded rangeland; yet it is a relative newcomer, having arrived on the scene only a little over a century ago. It first entered the West as an unknown but probably small number of seeds in contaminated grain or packing...
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Directory of Open Access Journals (Sweden)
Lynn Huntsinger
2014-03-01
Full Text Available When attempting to value ecosystem services and support their production, two critical aspects may be neglected. The term "ecosystem services" implies that they are a function of natural processes; yet, human interaction with the environment may be key to the production of many. This can contribute to a misconception that ecosystem service production depends on, or is enhanced by, the coercion or removal of human industry. Second, in programs designed to encourage ecosystem service production and maintenance, too often the inter-relationship of such services with social and ecological processes and drivers at multiple scales is ignored. Thinking of such services as "social-ecological services" can reinforce the importance of human culture, perspectives, and economies to the production of ecosystem services. Using a social-ecological systems perspective, we explore the integral role of human activity and decisions at pasture, ranch, and landscape scales. Just as it does for understanding ecosystems, a hierarchical, multiscaled framework facilitates exploring the complexity of social-ecological systems as producers of ecosystem services, to develop approaches for the conservation of such services. Using California's Mediterranean rangelands as a study area, we suggest that using a multiscaled approach that considers the importance of the differing drivers and processes at each scale and the interactions among scales, and that incorporates social-ecological systems concepts, may help avoid mistakes caused by narrow assumptions about "natural" systems, and a lack of understanding of the need for integrated, multiscaled conservation programs.
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Problems in implementing improved range management on ...
African Journals Online (AJOL)
Keywords: Africa; Australia; Livestock development; Pastoral communities; Rangeland development; Rangeland systems; Sustainability; development; ecology; holism; pastoralism; range management; strategies; environment; water; health; crop production; rangelands; resource management; north africa; holistic approach ...
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Multiscale sagebrush rangeland habitat modeling in the Gunnison Basin of Colorado
Homer, Collin G.; Aldridge, Cameron L.; Meyer, Debra K.; Schell, Spencer J.
2013-01-01
North American sagebrush-steppe ecosystems have decreased by about 50 percent since European settlement. As a result, sagebrush-steppe dependent species, such as the Gunnison sage-grouse, have experienced drastic range contractions and population declines. Coordinated ecosystem-wide research, integrated with monitoring and management activities, is needed to help maintain existing sagebrush habitats; however, products that accurately model and map sagebrush habitats in detail over the Gunnison Basin in Colorado are still unavailable. The goal of this project is to provide a rigorous large-area sagebrush habitat classification and inventory with statistically validated products and estimates of precision across the Gunnison Basin. This research employs a combination of methods, including (1) modeling sagebrush rangeland as a series of independent objective components that can be combined and customized by any user at multiple spatial scales; (2) collecting ground measured plot data on 2.4-meter QuickBird satellite imagery in the same season the imagery is acquired; (3) modeling of ground measured data on 2.4-meter imagery to maximize subsequent extrapolation; (4) acquiring multiple seasons (spring, summer, and fall) of Landsat Thematic Mapper imagery (30-meter) for optimal modeling; (5) using regression tree classification technology that optimizes data mining of multiple image dates, ratios, and bands with ancillary data to extrapolate ground training data to coarser resolution Landsat Thematic Mapper; and 6) employing accuracy assessment of model predictions to enable users to understand their dependencies. Results include the prediction of four primary components including percent bare ground, percent herbaceous, percent shrub, and percent litter, and four secondary components including percent sagebrush (Artemisia spp.), percent big sagebrush (Artemisia tridentata), percent Wyoming sagebrush (Artemisia tridentata wyomingensis), and shrub height (centimeters
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Chaplin-Kramer, R.; Kowal, V. A.; Sharp, R.
2017-12-01
Managing and monitoring supply chain sustainability is a major challenge and opportunity for business, especially in rangelands, heavily managed and often degraded natural systems that provide significant resources and raw materials for production. One of the largest and most threatened rangeland systems in the world is in Mongolia, which has seen a rapid rise in grazing pressure due to increasing global demand for cashmere along with privatization of a formerly government-run livestock industry. A new opportunity is emerging for remote-sensing to improve the management decisions of the producers and their incentive-setters, leading to a more sustainable rangeland system and better outcomes for biodiversity and people in this unique and imperiled landscape. Oyu Tolgoi (OT), the Mongolian subsidiary of the mining company Rio Tinto, in cooperation with Kering, an apparel conglomerate that sources cashmere from the region, are providing financial incentives to improve grazing patterns through a Sustainable Cashmere program, in order to restore the degraded rangeland ecosystem in the Gobi desert region. We present a framework and approach for predicting the effect of changing grazing practices on biodiversity and ecosystem services, which we are developing into decision-support tools for OT, Kering, and their local partner Wildlife Conservation Society to quantify the impacts of their programs and where these interventions will have greatest benefit. Our approach integrates remote-sensing and ecosystem modeling to scale up field monitoring data and forecast future impacts. Our rangeland production model, based on the soil-vegetation model CENTURY and the livestock model GRAZPLAN, predicts biomass production and plant species composition changes, and can feed into ecosystem services models such as soil retention and water regulation in the InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) software suite. This presents a significant advance in ecosystem
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Vulnerability of the Tibetan Pastoral Systems to Climate and Global Change
Directory of Open Access Journals (Sweden)
Yang Wang
2014-12-01
Full Text Available The impacts of climate and global change on Tibetan pastoral systems have become increasingly evident. Thus, a significant research endeavor is to explore the combined effects of these changes on the livelihoods of herder households and communities, on the adaptation strategies they adopted to respond to the current and expected risks associated with these changes, and on the emerging opportunities that can strengthen their resilience and adaptive capacity. We performed an integrated analysis of the dynamics of Tibetan pastoral systems influenced by climate and global changes by using the analytical framework developed by Ostrom. Climate and global changes have significantly altered the attributes of and the interactions within Tibetan pastoral systems, thus posing great challenges to their sustainable development. We used Nagqu County, a remote area of the northern Tibetan Plateau of China, as a case study to analyze the adaptation strategies adopted by local herders to respond to multiple stressors, as well as the emerging opportunities that they can take advantage of to increase their adaptive capacity. Findings show that although local herders have developed various adaptation strategies, such as planting forage grass, buying fodder from the market, renting pastures, joining formal or informal cooperatives, and diversifying livelihoods, social, cultural, and institutional challenges still exist. To enhance the adaptive capacity of herders and to reduce their vulnerability, we recommend that future rangeland policies and programs promote: (1 comprehensive support for formal or informal pastoral cooperatives, (2 development of the rangeland economy to take advantage of the multifunctionalities of rangeland ecosystems, and (3 revitalization of the mobility paradigm to allow the flexible use of rangelands.
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Directory of Open Access Journals (Sweden)
J. Kakeh
2016-09-01
Full Text Available Introduction: Physical and biological soil crusts are the principal types of soil crusts. Physical and biological soil crusts are distributed in arid, semi-arid and sub-humid regions which constitute over 40% of the earth terrestrial surface. Biological soil crusts (BSCs result from an intimate association between soil particles and cyanobacteria, algae, fungi, lichens and mosses in different proportions which live on the surface, or in the immediately uppermost millimeters of soil. Some of the functions that BSCs influences include: water absorption and retention, nutrient retention, Carbon and nitrogen fixation, biological activate and hydrologic Status. BSCs are important from the ecological view point and their effects on the environment, especially in rangeland, and desert ecosystems and this caused which researchers have a special attention to this component of the ecosystems more than before. Materials and Methods: This study carried out in the Qara Qir rangelands of Golestan province, northeast of Iran (37º15′ - 37º23′ N &54º33′ -54º39′ E, to investigate the effects of BSCs on some of soil biological properties. Four sites including with and without BSCs cover were selected. Soil biological properties such as microbial populations, soil respiration, microbial biomass carbon and nitrogen, as well as, other effective properties such asorganic carbon percent, total nitrogen, electrical conductivity, and available water content were measured in depths of 0-5 and 5-15 cm of soil with four replications. The gathered data were analyzed by nested plot, and the mean values were compared by Duncan test. Results and Discussion: The results showed that organic carbon and water content were higher at the surface under BSCs, followed by 5-15 cm soils under BSCs. Both soil depths of uncrusted soils showed substantially lower organic carbon and water content than the BSC-covered soils. Total nitrogen was far higher in BSC-encrusted surface
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Francisco, C L; Cooke, R F; Marques, R S; Mills, R R; Bohnert, D W
2012-12-01
Two experiments evaluated the effects of temperament and acclimation to handling on performance of Angus × Hereford feeder cattle reared in extensive rangeland systems until weaning. In Exp. 1, 200 calves (n = 97 for yr 1; n = 103 for yr 2) were evaluated for temperament at weaning (average age ± SE = 152 ± 1 d) by chute score and exit velocity. Chute score was assessed on a 5-point scale according to behavior during chute restraining. Exit score was calculated by dividing exit velocity into quintiles and assigning calves a score from 1 (slowest) to 5 (fastest). A temperament score was calculated for each calf by averaging chute and exit scores. Calf temperament was classified according to temperament score as adequate (≤3) or excitable (>3). After weaning, calves were assigned to a 40-d preconditioning followed by growing (139 d) and finishing (117 d) phases until slaughter. Weaning BW was decreased (P = 0.04) in excitable calves compared with adequate calves. No differences were detected (P ≥ 0.21) for ADG during preconditioning, growing, and finishing phases; hence, excitable calves tended (P = 0.09) to have decreased HCW compared with adequate calves. In Exp. 2, 60 steers (initial age ± SE = 198 ± 2 d) were weighed and evaluated for temperament score 35 d after weaning (d -29). On d -28, steers were ranked by these variables and assigned to receive an acclimation treatment or not (control). Acclimated steers were processed through a handling facility twice weekly for 4 wk (d -28 to -1) whereas control steers remained undisturbed on pasture. On d 0, all steers were transported for 24 h and returned to the research facility (d 1). On arrival, steers were ranked by BW within treatment and randomly assigned to 20 feedlot pens for a 28-d feedlot receiving period. Acclimated steers had decreased temperament score and plasma cortisol compared with controls on d 0 (P = 0.02). During feedlot receiving, acclimated steers had decreased ADG (P < 0.01) and G:F (P
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Bohrer, Stefanie L; Limb, Ryan F; Daigh, Aaron L; Volk, Jay M; Wick, Abbey F
2017-03-01
Rangelands are described as heterogeneous, due to patterning in species assemblages and productivity that arise from species dispersal and interactions with environmental gradients and disturbances across multiple scales. The objectives of rangeland reclamation are typically vegetation establishment, plant community productivity, and soil stability. However, while fine-scale diversity is often promoted through species-rich seed mixes, landscape heterogeneity and coarse-scale diversity are largely overlooked. Our objectives were to evaluate fine and coarse-scale vegetation patterns across a 40-year reclamation chronosequence on reclaimed surface coalmine lands. We hypothesized that both α-diversity and β-diversity would increase and community patch size and species dissimilarity to reference sites would decrease on independent sites over 40 years. Plant communities were surveyed on 19 post-coalmine reclaimed sites and four intact native reference sites in central North Dakota mixed-grass prairie. Our results showed no differences in α or β-diversity and plant community patch size over the 40-year chronosequence. However, both α-diversity and β-diversity on reclaimed sites was similar to reference sites. Native species establishment was limited due to the presence of non-native species such as Kentucky bluegrass (Poa pratensis) on both the reclaimed and reference sites. Species composition was different between reclaimed and reference sites and community dissimilarity increased on reclaimed sites over the 40-year chronosequence. Plant communities resulting from reclamation followed non-equilibrium succession, even with consistent seeds mixes established across all reclaimed years. This suggests post-reclamation management strategies influence species composition outcomes and land management strategies applied uniformly may not increase landscape-level diversity.
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Boyte, Stephen; Wylie, Bruce K.; Rigge, Matthew B.; Dahal, Devendra
2018-01-01
Data fused from distinct but complementary satellite sensors mitigate tradeoffs that researchers make when selecting between spatial and temporal resolutions of remotely sensed data. We integrated data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor aboard the Terra satellite and the Operational Land Imager sensor aboard the Landsat 8 satellite into four regression-tree models and applied those data to a mapping application. This application produced downscaled maps that utilize the 30-m spatial resolution of Landsat in conjunction with daily acquisitions of MODIS normalized difference vegetation index (NDVI) that are composited and temporally smoothed. We produced four weekly, atmospherically corrected, and nearly cloud-free, downscaled 30-m synthetic MODIS NDVI predictions (maps) built from these models. Model results were strong with R2 values ranging from 0.74 to 0.85. The correlation coefficients (r ≥ 0.89) were strong for all predictions when compared to corresponding original MODIS NDVI data. Downscaled products incorporated into independently developed sagebrush ecosystem models yielded mixed results. The visual quality of the downscaled 30-m synthetic MODIS NDVI predictions were remarkable when compared to the original 250-m MODIS NDVI. These 30-m maps improve knowledge of dynamic rangeland seasonal processes in the central Great Basin, United States, and provide land managers improved resource maps.
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Forage quality and availability for large herbivores in Southern African rangelands
CSIR Research Space (South Africa)
Stolter, C
2018-04-01
Full Text Available nitrogen concentration) but instead balance their diet among diff erent plant compounds not only to satisfy their nu- tritional needs (nutrient balancing; see Felton et al., 2016; Simpson & Rauben- heimer, 2012; Westoby, 1974) but also to avoid negative...?’, Stolter et al., 2018). This balanc- ing act is often refl ected by the ingestion of a high variety of food plants (so-called diet-mixing [Villalba et al., 2002]), which can be fulfi lled only in a heterogeneous, diverse environment. Diff erent feeding...
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Evaluation the impact of habitat quality on the soil fauna in Jajarm region
Directory of Open Access Journals (Sweden)
G.A. Rassam
2016-04-01
Full Text Available The effects of land use, crop type and crop management on soil fauna were investigated with survey of four habitats in Jajarm. The habitats included rangelands, alfalfa (Medicago sativa L. fields and low-input and high-input of wheat (Triticum aestivum L. fields, each with four sample units. In each sample unit, the macrofauna collected with pitfall traps, sorted and counted in terms of family. The analysis of data conducted using of contrast analysis, analysis of similarities and principal component analysis (PCA. In rangelands the taxonomic richness, Simpson diversity index and abundance of macrofauna families tremendously were lower than agricultural habitats. These were attributed to low of plant diversity and pressure of livestock grazing. In alfalfa fields, increased abundance of beneficial macrofauna than wheat fields due to use not of chemical inputs, low disturbance and perennial of alfalfa. The crop management dad not has any significant impact on soil macrofauna. However, soil important macrofauna showed great tendency to occupancy in low-input wheat fields.
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Directory of Open Access Journals (Sweden)
Arne B.R. Witt
2017-05-01
Full Text Available This article provides a preliminary list of alien plant species in the Serengeti-Mara ecosystem in East Africa. The list is based on broad-scale roadside surveys in the area and is supplemented by more detailed surveys of tourist facilities in the Masai-Mara National Reserve and adjoining conservancies. We encountered 245 alien plant species; significantly more than previous studies, of which 62 (25% were considered to have established self-perpetuating populations in areas away from human habitation. These included species which had either been intentionally or accidentally introduced. Of the 245 alien plants, 212 (including four species considered to be native to the region were intentionally introduced into gardens in the National Reserve and 51 (24% had established naturalised populations within the boundaries of these tourism facilities. Of the 51 naturalised species, 23 (11% of the 212 alien species were recorded as being invasive within the ecosystem, outside of lodges and away from other human habitation. Currently, the Serengeti-Mara ecosystem is relatively free of widespread and abundant invasive alien plants, with a few exceptions, but there are extensive populations outside of the ecosystem, particularly to the west, from where they could spread. We address the potential impacts of six species that we consider to pose the highest risks (Parthenium hysterophorus, Opuntia stricta, Tithonia diversifolia, Lantana camara, Chromolaena odorata and Prosopis juliflora. Although invasive alien plants pose substantial threats to the integrity of the ecosystem, this has not yet been widely recognised. We predict that in the absence of efforts to contain, or reverse the spread of invasive alien plants, the condition of rangelands will deteriorate, with severe negative impacts on migrating large mammals, especially wildebeest, zebra and gazelles. This will, in turn, have a substantial negative impact on tourism, which is a major economic activity
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Effects of grazing and fire on herbaceous species in the Bolivian Altiplano
Aguilar, Lita Beatriz Patty
2012-01-01
High mountain rangelands had been under human land use for millennia in most parts of the world. Traditional land care systems led to highly diverse and stable ecosystems. As these traditions fade and population pressure rises, these grassland systems become overgrazed, lose carrying capacity and biodiversity and become eroded. Semi-arid high elevation pastures in tropical and subtropical regions are particularly endangered. This PhD project aimed at assessing the plant invento...
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Directory of Open Access Journals (Sweden)
Vinicius Ferreira Chaves de Souza
Full Text Available ABSTRACT Water erosion is the main cause of soil degradation and is influenced by rainfall, soil, topography, land use, soil cover and management, and conservation practices. The objective of this study was to quantify water erosion in a Humic Dystrudept in two experiments. In experiment I, treatments consisted of different rates of fertilizer applied to the soil surface under no-tillage conditions. In experiment II, treatments consisted of a no-tillage in natural rangeland, burned natural rangeland and natural rangeland. Forage turnip, black beans, common vetch, and corn were used in rotation in the treatments with crops in the no-tillage during study period. The treatments with crops and the burned rangeland and natural rangeland were compared to a bare soil control, without cultivation and without fertilization. Increasing fertilization rates increased organic carbon content, soil resistance to disintegration, and the macropore volume of the soil, due to the increase in the dry mass of the crops, resulting in an important reduction in water erosion. The exponential model of the ŷ = ae-bx type satisfactorily described the reduction in water and soil losses in accordance with the increase in fertilization rate and also described the decrease in soil losses in accordance with the increase in dry mass of the crops. Water erosion occurred in the following increasing intensity: in natural rangeland, in cultivated natural rangeland, and in burned natural rangeland. Water erosion had less effect on water losses than on soil losses, regardless of the soil management practices.
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Use of UAVs for Remote Measurement of Vegetation Canopy Variables
Rango, A.; Laliberte, A.; Herrick, J.; Steele, C.; Bestelmeyer, B.; Chopping, M. J.
2006-12-01
Remote sensing with different sensors has proven useful for measuring vegetation canopy variables at scales ranging from landscapes down to individual plants. For use at landscape scales, such as desert grasslands invaded by shrubs, it is possible to use multi-angle imagery from satellite sensors, such as MISR and CHRIS/Proba, with geometric optical models to retrieve fractional woody plant cover. Vegetation community states can be mapped using visible and near infrared ASTER imagery at 15 m resolution. At finer scales, QuickBird satellite imagery with approximately 60 cm resolution and piloted aircraft photography with 25-80 cm resolution can be used to measure shrubs above a critical size. Tests conducted with the QuickBird data in the Jornada basin of southern New Mexico have shown that 87% of all shrubs greater than 2 m2 were detected whereas only about 29% of all shrubs less than 2 m2 were detected, even at these high resolutions. Because there is an observational gap between satellite/aircraft measurements and ground observations, we have experimented with Unmanned Aerial Vehicles (UAVs) producing digital photography with approximately 5 cm resolution. We were able to detect all shrubs greater than 2 m2, and we were able to map small subshrubs indicative of rangeland deterioration, as well as remnant grass patches, for the first time. None of these could be identified on the 60 cm resolution data. Additionally, we were able to measure canopy gaps, shrub patterns, percent bare soil, and vegetation cover over mixed rangeland vegetation. This approach is directly applicable to rangeland health monitoring, and it provides a quantitative way to assess shrub invasion over time and to detect the depletion or recovery of grass patches. Further, if the UAV images have sufficient overlap, it may be possible to exploit the stereo viewing capabilities to develop a digital elevation model from the orthophotos, with a potential for extracting canopy height. We envision two
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Chambers, Jeanne C.; Beck, Jeffrey L.; Bradford, John B.; Bybee, Jared; Campbell, Steve; Carlson, John; Christiansen, Thomas J; Clause, Karen J.; Collins, Gail; Crist, Michele R.; Dinkins, Jonathan B.; Doherty, Kevin E.; Edwards, Fred; Espinosa, Shawn; Griffin, Kathleen A.; Griffin, Paul; Haas, Jessica R.; Hanser, Steven E.; Havlina, Douglas W.; Henke, Kenneth F.; Hennig, Jacob D.; Joyce, Linda A; Kilkenny, Francis F.; Kulpa, Sarah M; Kurth, Laurie L; Maestas, Jeremy D; Manning, Mary E.; Mayer, Kenneth E.; Mealor, Brian A.; McCarthy, Clinton; Pellant, Mike; Perea, Marco A.; Prentice, Karen L.; Pyke, David A.; Wiechman , Lief A.; Wuenschel, Amarina
2017-01-01
The Science Framework is intended to link the Department of the Interior’s Integrated Rangeland Fire Management Strategy with long-term strategic conservation actions in the sagebrush biome. The Science Framework provides a multiscale approach for prioritizing areas for management and determining effective management strategies within the sagebrush biome. The emphasis is on sagebrush (Artemisia spp.) ecosystems and Greater sage-grouse (Centrocercus urophasianus). The approach provided in the Science Framework links sagebrush ecosystem resilience to disturbance and resistance to nonnative, invasive plant species to species habitat information based on the distribution and abundance of focal species. A geospatial process is presented that overlays information on ecosystem resilience and resistance, species habitats, and predominant threats and that can be used at the mid-scale to prioritize areas for management. A resilience and resistance habitat matrix is provided that can help decisionmakers evaluate risks and determine appropriate management strategies. Prioritized areas and management strategies can be refined by managers and stakeholders at the local scale based on higher resolution data and local knowledge. Decision tools are discussed for determining appropriate management actions for areas that are prioritized for management. Geospatial data, maps, and models are provided through the U.S. Geological Survey (USGS) ScienceBase and Bureau of Land Management (BLM) Landscape Approach Data Portal. The Science Framework is intended to be adaptive and will be updated as additional data become available on other values and species at risk. It is anticipated that the Science Framework will be widely used to: (1) inform emerging strategies to conserve sagebrush ecosystems, sagebrush dependent species, and human uses of the sagebrush system, and (2) assist managers in prioritizing and planning on-the-ground restoration and mitigation actions across the sagebrush biome.
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A checklist of the flora of Shanjan protected area, East Azerbaijan Province, NW Iran.
Bibalani, Ghassem Habibi; Taheri, Elnaz
2013-01-01
The flora of protected Shanjan rangeland in Shabestar district, Azerbaijan Province, NW Iran was studied using a 1 m × 1 m quadrate in spring and summer 2011. The climate of this area is cold and dry. In this area 94 plant species belonging to 25 families were identified as constituting the major part of the vegetation. The families in the area are Amaryllidaceae, Boraginaceae, Campanulaceae, Caryophllaceae, Cistaceae, Compositea, Cruciferae, Cyperaceae, Dipesaceae, Euphorbiaceae, Geraniaceae, Hypericaceae, Linaceae, Melvaceae, Orobachaceae, Papaveraceae, Paronychiaceae, Plantaginaceae, Polygolaceae, Ranunculaceae, Resedaceae, Rubiaceae, Scrophulariaceae, Solanaceae and Valerianacea. Floristic composition is Irano-Turanian elements. Detailed analysis showed that Biennial plants were 3.19%, Annual 41.49% and Perennial 55.32%.
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Root proliferation in native perennial grasses of arid Patagonia, Argentina
Institute of Scientific and Technical Information of China (English)
Yanina A. TORRES; Mara M. MUJICA; Sandra S. BAIONI; Jos ENTO; Mara N. FIORETTI; Guillermo TUCAT; Carlos A. BUSSO; Oscar A. MONTENEGRO; Leticia ITHURRART; Hugo D. GIORGETTI; Gustavo RODRGUEZ; Diego BENTIVEGNA; Roberto E. BREVEDAN; Osvaldo A. FERNNDEZ
2014-01-01
Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that (1) defoliation reduce net primary productivity, and root length density and weight in the native species, and (2) root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species (i.e., Aristida spegazzinii, A. subulata and Sporobolus cryptandrus). Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season (2008-2009), cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid-and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den-sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.
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Choice Options to Meet Household Food Security in the Cattle Corridor of Uganda
Directory of Open Access Journals (Sweden)
Betty Mbolanyi
2017-01-01
Full Text Available This study identified the major options adopted by households in the rangelands of Uganda to meet their food needs, the factors that affect their choices and barriers to making use of various choices. A cross-sectional survey using semi-structured questionnaires was administered among 180 pastoral households in selected rangeland area of Uganda. The options identified include restocking animals, changing planting dates, soil conservation, harnessing new technologies, planting trees and buying food stuffs. Analysis of results from the multinomial logistic model indicated that age, level of education, size of household, years in current location, farm income, non-farm income, livestock ownership, access to extension services and climate and weather information were key determinants of farmers’ choice of options to realize household food security. The major perceived barriers to choice options were lack of information on alternative options, poor technologies, climate variability, inadequate land, high food prices and low income. The analysis of choice of options to meet household food security suggests a number of different policy options such as strengthening production facilitation options available to pastoral communities including among others access to affordable credit, investing in yield-increasing technologies, introduction of livestock species that are better suited to drier conditions, raising awareness on climate related variations, creating opportunities for off-farm employment, encouraging pastoralists to grow more crops, and investing in irrigation.
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CSIR Research Space (South Africa)
Dube, S
2011-01-01
Full Text Available on the upper horizon of the soil profile. Grasses are assumed to extract water from the top soil layer (0 - 15 cm) due to their shallow rooting characteristics, while trees and bushes derive their nutrients from the lower layers (Wiegand et al., 2006... and slower degradation rates than soils with a 10 year history of asparagus management and associated bromacil use. 6. The economic implications of bromacil application methods on rangelands encroached by Acacia karroo The encroachment of woody plants...
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CSIR Research Space (South Africa)
Yapi, T
2012-10-01
Full Text Available ecosystems (Robles and Chapin, 1995). Invasive alien tree species and shrubs negatively affect ecosystems in various ways, and often result in a decline in benefits that people derive from the functioning of these systems ? or ecosystem services... the ecological impacts of the invasive alien plant species, Acacia mearnsii, on the function and productivity of rangelands in South Africa and their ability to sustain livestock production. AIM The central aim of this research is to develop a deeper...
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Field test of a new Australian method of rangeland monitoring
Suzanne Mayne; Neil West
2001-01-01
Managers need more efficient means of monitoring changes on the lands they manage. Accordingly, a new Australian approach was field tested and compared to the Daubenmire method of assessing plant cover, litter, and bare soil. The study area was a 2 mile wide by 30.15 mile long strip, mostly covered by salt desert shrub ecosystem types, centered along the SE boundary of...
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Energy Technology Data Exchange (ETDEWEB)
Robert Paul Breckenridge
2007-05-01
feasible and can collect imagery for very large areas in a short period of time. It was accurate for bare ground and grasses. Both UAV systems have limitations, but these will be reduced as the technology advances. In both cases, the UAV systems collected data at a much faster rate than possible on the ground. The study concluded that improvements in automating the image processing efforts would greatly improve use of the technology. In the near future, UAV technology may revolutionize rangeland monitoring in the same way Global Positioning Systems have affected navigation while conducting field activities.
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Sustainable intensification of cultivated pastures using multiple ...
African Journals Online (AJOL)
rangeland and wildlife parks) for guidelines to implementing this approach in cultivated pasture. In rangeland or natural grassland ... Keywords: animal production, biodiversity, cultivated pastures, foraging ecology, plant–herbivore interactions ...
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International Nuclear Information System (INIS)
Laundre, J.W.
1990-05-01
The major goal of radioactive waste management is long-term containment of radioactive waste. Long-term containment is dependent on understanding water movement on, into, and through trench caps. Several computer simulation models are available for predicting water movement. Of the several computer models available, CREAMS (Chemicals, Runoff, and Erosion from Agricultural Management Systems) and ERHYM-II (Ekalaka Rangeland Hydrology and Yield Model) were tested for use on the Idaho National Engineering Laboratory (INEL). The models were calibrated, tested for sensitivity, and used to evaluate some basic trench cap designs. Each model was used to postdict soil moisture, evapotranspiration, and runoff of two watersheds for which such data were already available. Sensitivity of the models was tested by adjusting various input parameters from high to low values and then comparing model outputs to those generated from average values. Ten input parameters of the CREAMS model were tested for sensitivity. 17 refs., 23 figs., 20 tabs
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Pulido, Manuel; Schnabel, Susanne; Francisco Lavado Contador, Joaquín; Miralles Mellado, Isabel
2016-04-01
Rangelands in SW Spain occupy a total surface area of approximately 6 million ha and constitute the most representative extensive ranching system of the Iberian Peninsula gathering more than 13 million livestock heads. They are characterised by an herbaceous layer, mostly composed of therophytic species, with a disperse tree cover, mainly holm oak and cork oak (Quercus ilex rotundifolia and Q. suber), interspersed with shrubs in many places. This type of land system is of ancient origin and experienced frequent changes in land use in the past, since agricultural, livestock and forestry activities have coexisted within the same farms. In recent decades, livestock farming has become dominant due, in part, to the subsidies of the Common Agriculture Policy. Since Spain joined the European Union in 1986 until the year 2000, the number of domestic animals doubled, particularly cattle, and consequently animal stocking rates have increased on average from 0.40 AU ha-1 up to 0.70 AU ha-1. This increase in animal stocking rates, along with a progressive substitution of cattle instead of sheep in many farms, has led to the occurrence of land degradation processes such as the reduction of grass cover or soil compaction in heavily grazed areas. Previous research has evidenced higher values of soil bulk density and resistance to penetration as well as larger bare surface areas in spring in fenced areas with animal stocking rates above 1 AU ha-1. However, a better understanding of how increasing bulk density or resistance to penetration influence the frequency of herbaceous roots and how a reduction in the frequency of roots affects soil organic matter content in rangelands is still unknown. Therefore, the main goal of this study was to determine possible relationships between the frequencies of herbaceous roots and soil organic matter content in order to understand the effect of excessive animal numbers on the depletion of soil fertility by reducing progressively the quantity of
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Crested wheatgrass-cheatgrass seedling competition in a mixed-density design
Francis, Mark G.; Pyke, David A.
1996-01-01
Plant competition experiments have historically used designs that are difficult to interpret due to confounding problems. Recently, designs based on a 'response function' approach have been proposed and tested in various plant mixture settings. For this study, 3 species were used that are important in current revegetation practices in the Intermountain West. 'Nordan' (Agropyron desertorum [Fish. ex Link] Shult.) and 'Hycrest' (A. cristatum [L.] Gaertn. x desertorum) crested wheatgrass are commonly-used revegetation species on rangelands susceptible to cheatgrass (Bromus tectorum L.) invasion, although little quantitative data exist that compare their competitive abilities. We evaluated the competitive ability of Hycrest and Nordan seedlings in 2-species mixtures with cheatgrass in a greenhouse study. Linear and nonlinear models were developed for a range of densities (130- 520 seeds m-2) for each species to predict median above-ground biomass and tiller numbers and to further test the usefulness of this design for evaluating species to rehabilitate rangelands. In both experiments, increasing Hycrest and Nordan densities reduced their own biomass and tiller production while increasing Hycrest densities reduced cheatgrass biomass and tiller production. Nordan did not affect cheatgrass biomass and tiller production. However, increasing cheatgrass densities reduced Hycrest and Nordan biomass and tiller production, and its own biomass and tiller production. The competition index i.e. substitution rate, indicated that Hycrest seedlings were better competitors with cheatgrass than Nordan, although in all mixtures, cheatgrass plants were the superior competitors. Further field research using this design, where environmental inputs are less optimal and diverse, is needed to validate these results and to further evaluate the use of this approach in examining effects of intra- and interspecific competition.
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CSIR Research Space (South Africa)
Fisher, J
2009-07-01
Full Text Available Factors influencing woody savanna vegetation structure across a land-use gradient of intensity (highly and lightly utilized communal rangeland) and type (national protected area, private game reserve and communal rangelands) were investigated. Small...
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Plant host finding by parasitic plants: a new perspective on plant to plant communication.
Mescher, Mark C; Runyon, Justin B; De Moraes, Consuelo M
2006-11-01
Plants release airborne chemicals that can convey ecologically relevant information to other organisms. These plant volatiles are known to mediate a large array of, often complex, interactions between plants and insects. It has been suggested that plant volatiles may have similar importance in mediating interactions among plant species, but there are few well-documented examples of plant-to-plant communication via volatiles, and the ecological significance of such interactions has been much debated. To date, nearly all studies of volatile-mediated interactions among plant species have focused on the reception of herbivore-induced volatiles by neighboring plants. We recently documented volatile effects in another system, demonstrating that the parasitic plant Cuscuta pentagona uses volatile cues to locate its hosts. This finding may broaden the discussion regarding plant-to-plant communication, and suggests that new classes of volatile-meditated interactions among plant species await discovery.
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Relationship between gully erosion and hydrology in a small rangeland catchment
Gómez, Á.; Schnabel, S.; Sanjosé Blasco, J. J.; Lavado Contador, J. F.
2009-04-01
Gully erosion plays an important role in degradation processes of Mediterranean environments. Relatively little is known about relationships between gully erosion rates and rainfall or discharge in these areas. The aims of this work are: quantifying gully erosion, analyzing its spatial and temporal variability and evaluating its relationships with catchment hydrology. The study was carried out in a small catchment (99.5 ha) located in the SW of the Iberian Peninsula. The topography is undulated with an average slope of 7.6%. Climate is Mediterranean with a pronounced dry season. Annual and inter-annual rainfall variation is high with an annual average of 510 mm. Vegetation cover is formed by a tree layer of Holm oaks (Quercus rotundifolia) and an herbaceous layer characterized by therophytes. The land use is representative of wooded rangelands (dehesa) land use and is based on grazing by sheep and seasonally by pigs. The channel is a valley bottom discontinuous gully incised into an alluvial sediment fill of approximately 1.5 m. The gully is a second order channel with a tributary joining the main branch at 174 m from the basin outlet. Mean width and depth of the gully is 3.3 m an 0.6 m, respectively. The main channel presents several headcuts along its course including one in the upper limit, while the tributary presents 2 very active headcuts close to the junction. Gully erosion or accumulation volume was obtained by means of 28 fixed cross sections measured with a frequency of 6 months during the period 2001-2007. Cross sections were measured using a laser total station which allows increasing the profile resolution in critical areas (such us bank toes or channel bed). Discharge was determined using a water depth probe installed in a weir at the outlet of the catchment. Rainfall was registered by means of 6 tipping bucket rain gauges distributed over the catchment. Both discharge and rainfall were registered with a resolution of 5 minutes. Results showed a total
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Rangelands are valued for their capacity to provide diverse suites of ecosystem services, from food production to carbon storage to biological diversity. Although rangelands worldwide share common characteristics, differences among biogeographic regions result in differences in the types of opportun...
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African Journal of Range and Forage Science
African Journals Online (AJOL)
The African Journal of Range & Forage Science is the leading rangeland and pastoral journal in Africa. The Journal is dedicated to publishing quality original material that advances rangeland ecology and pasture management in Africa. Read more abou the journal here.
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Rangeland managers and scientists are in need of predictive tools to accurately simulate post-fire hydrologic responses and provide hydrologic risk assessment. Rangeland hydrologic modeling has advanced in recent years; however, model advancements have largely been associated with data from gently ...
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Purple threeawn (Aristida purpurea Nutt. varieties) is a native grass capable of increasing on rangelands, forming near monocultures, and creating a stable state. Productive rangelands throughout the Great Plains and Intermountain West have experienced increases in purple threeawn abundance, reduci...
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Munn, A J; Dawson, T J; McLeod, S R; Dennis, T; Maloney, S K
2013-08-01
We used doubly labelled water to measure field metabolic rates (FMR) and water turnover rates (WTR) in one of Australia's largest native herbivores, the red kangaroo (Macropus rufus) and one of Australia's dominant livestock species, the wool-breed Merino sheep, under free-living conditions in a typical Australian rangeland. Also, we used GPS technology to examine animal space use, along with the comparisons of urine concentration, diet, diet digestibility, and subsequent grazing pressures. We found smaller space-use patterns than previously reported for kangaroos, which were between 14 and 25 % those of sheep. The FMR of a 25-kg kangaroo was 30 % that of a 45-kg sheep, while WTR was 15 % and both were associated with smaller travel distances, lower salt intakes, and higher urine concentration in kangaroos than sheep. After accounting for differences in dry matter digestibility of food eaten by kangaroos (51 %) and sheep (58 %), the relative grazing pressure of a standard (mature, non-reproductive) 25-kg kangaroo was 35 % that of a 45-kg sheep. Even for animals of the same body mass (35 kg), the relative grazing pressure of the kangaroo was estimated to be only 44 % that of the sheep. After accounting for the energetic costs of wool growth by sheep, the FMRs of our sheep and kangaroos were 2-3 times their expected BMRs, which is typical for mammalian FMR:BMRs generally. Notably, data collected from our free-living animals were practically identical to those from animals confined to a semi-natural enclosure (collected in an earlier study under comparable environmental conditions), supporting the idea that FMRs are relatively constrained within species.
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Plant Host Finding by Parasitic Plants: A New Perspective on Plant to Plant Communication
Mescher, Mark C; Runyon, Justin B; De Moraes, Consuelo M
2006-01-01
Plants release airborne chemicals that can convey ecologically relevant information to other organisms. These plant volatiles are known to mediate a large array of, often complex, interactions between plants and insects. It has been suggested that plant volatiles may have similar importance in mediating interactions among plant species, but there are few well-documented examples of plant-to-plant communication via volatiles, and the ecological significance of such interactions has been much d...
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Hien, F.G.
1995-01-01
Sahelian rangelands are subject to degradation caused by physical and human factors. This report presents the results of recent research in Burkina Faso on methods for regenerating such rangelands. It begins with an overview of existing regeneration methods. Quantitative ecological field work
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Monitoring of livestock grazing effects on Bureau of Land Management land
Veblen, Kari E.; Pyke, David A.; Aldridge, Cameron L.; Casazza, Michael L.; Assal, Timothy J.; Farinha, Melissa A.
2013-01-01
Public land management agencies, such as the Bureau of Land Management (BLM), are charged with managing rangelands throughout the western United States for multiple uses, such as livestock grazing and conservation of sensitive species and their habitats. Monitoring of condition and trends of these rangelands, particularly with respect to effects of livestock grazing, provides critical information for effective management of these multiuse landscapes. We therefore investigated the availability of livestock grazing-related quantitative monitoring data and qualitative region-specific Land Health Standards (LHS) data across BLM grazing allotments in the western United States. We then queried university and federal rangeland science experts about how best to prioritize rangeland monitoring activities. We found that the most commonly available monitoring data were permittee-reported livestock numbers and season-of-use data (71% of allotments) followed by repeat photo points (58%), estimates of forage utilization (52%), and, finally, quantitative vegetation measurements (37%). Of the 57% of allotments in which LHS had been evaluated as of 2007, the BLM indicated 15% had failed to meet LHS due to livestock grazing. A full complement of all types of monitoring data, however, existed for only 27% of those 15%. Our data inspections, as well as conversations with rangeland experts, indicated a need for greater emphasis on collection of grazing-related monitoring data, particularly ground cover. Prioritization of where monitoring activities should be focused, along with creation of regional monitoring teams, may help improve monitoring. Overall, increased emphasis on monitoring of BLM rangelands will require commitment at multiple institutional levels.
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Evaluating derived vegetation indices and cover fraction to estimate ...
African Journals Online (AJOL)
This study was conducted to assess satellite data for quantifying and mapping the spatial distribution of rangeland biophysical parameters (aboveground biomass) from different geographic locations in the North West province, South Africa. Two major factors affecting the quality and conditions of the rangelands, namely ...
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Low-dose glyphosate does not control annual bromes in the northern Great Plains
Annual bromes (downy brome and Japanese brome) have been shown to decrease perennial grass forage production and alter ecosystem functions in northern Great Plains rangelands. Large-scale chemical control might be a method for increasing rangeland forage production if low application rates confer co...
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Ferwerda, J.G.
2005-01-01
Rangeland carrying capacity is determined by both the quantity, as well as the quality, of forage. The estimation of the quantity of rangeland foliage and its spatial distribution has been studied and reliable results achieved. Traditional methods to determine quality involve collection of field
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Plant host finding by parasitic plants: A new perspective on plant to plant communication
Mark C. Mescher; Justin B. Runyon; Consuelo M. De Moraes
2006-01-01
Plants release airborne chemicals that can convey ecologically relevant information to other organisms. These plant volatiles are known to mediate a large array of, often complex, interactions between plants and insects. It has been suggested that plant volatiles may have similar importance in mediating interactions among plant species, but there are few well-...
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78 FR 73186 - Wallowa-Whitman National Forests, Oregon; Lower Imnaha Rangeland Analysis
2013-12-05
... could be contributing to a slow- moving erosion process in which soil is slowly being displaced and... been found in several isolated patches, all of which are in fescue (Festuca)--type vegetation habitat... analysis because these plants are primarily growing in north facing areas, the soils tend to be deeper, and...
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Nutritional and health challenges of pastoralist populations in Kenya ...
African Journals Online (AJOL)
This paper examines nutritional and health challenges facing pastoralists who inhabit fragile rangelands and are one of the most nutritionally vulnerable population groups in Kenya. The review is based on a synthesis of literature on pastoralist food security, nutrition and health status and livelihoods in Kenya's rangelands.
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Land-Use Influences Carbon Fluxes in Northern Kazakhstan
An understanding of carbon cycling is important to maintain sustainable rangeland ecosystems. Rangelands in the western U.S. are similar to those in Central Asia. We used a combination of meteorological and computer modeling techniques to quantitatively assess carbon loss and gain for four major l...
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African Journal of Range and Forage Science - Vol 20, No 2 (2003)
African Journals Online (AJOL)
Session A6 Rangelands as dynamic systems — Fragmentation of rangelands: ecological and economic implications. A tribute to Jim Ellis · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. TN Thompson Hobbs, Kathleen Galvin, 113-116. http://dx.doi.org/10.2989/ ...
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Linking phenology and biomass productivity in South Dakota mixed-grass prairie
Rigge, Matthew; Smart, Alexander; Wylie, Bruce; Gilmanov, Tagir; Johnson, Patricia
2013-01-01
Assessing the health of rangeland ecosystems based solely on annual biomass production does not fully describe plant community condition; the phenology of production can provide inferences on species composition, successional stage, and grazing impacts. We evaluate the productivity and phenology of western South Dakota mixed-grass prairie using 2000 to 2008 Moderate Resolution Imaging Spectrometer (MODIS) normalized difference vegetation index (NDVI) satellite imagery at 250 m spatial resolution. Growing season NDVI images were integrated weekly to produce time-integrated NDVI (TIN), a proxy of total annual biomass production, and integrated seasonally to represent annual production by cool (C3) and warm (C4) season species. Additionally, a variety of phenological indicators including cool season percentage of TIN were derived from the seasonal profiles of NDVI. Cool season percentage and TIN were combined to generate vegetation classes, which served as proxies of plant community condition. TIN decreased with precipitation from east to west across the study area. Alternatively, cool season percentage increased from east to west, following patterns related to the reliability (interannual coefficient of variation [CV]) and quantity of mid-summer precipitation. Cool season TIN averaged 76.8% of total. Seasonal accumulation of TIN corresponded closely (R2 > 0.90) to that of gross photosynthesis data from a carbon flux tower. Field-collected biomass and community composition data were strongly related to the TIN and cool season percentage products. The patterns of vegetation classes were responsive to topographic, edaphic, and land management influences on plant communities. Accurate maps of biomass production, cool/warm season composition, and vegetation classes can improve the efficiency of land management by adjusting stocking rates and season of use to maximize rangeland productivity and achieve conservation objectives. Further, our results clarify the spatial and
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Ecology, mobility and labour: dynamic pastoral herd management in an uncertain world.
Butt, B
2016-11-01
In this review, the author discusses how pastoralism, and its many constituent components, is increasingly being recognised as in tune with the changing political and ecological nature of rangelands. He describes ways in which the literature reflects this changing attitude, outlines how rangelands respond to changes in climate and explores the evolving use of livestock resources. In addition, he describes the growing recognition of factors other than livestock density that affect rangeland vegetation (i.e. density-independent relationships). The author explains how terms such as 'carrying capacity', 'overgrazing' and 'desertification' are often taken out of their social and political context when describing rangeland pastoralism. Next, he describes the growing recognition by the development community of the importance of the mobility model, particularly in relation to changing ecologies and politics. Finally, he outlines how labour, a central focus of pastoral herd management, is a fluid component of pastoral systems in response to changing political and ecological circumstances.
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Directory of Open Access Journals (Sweden)
Benjamin Goldstein
Full Text Available The food demands of the United States (US impart significant environmental pressures. The high rate of consumption of beef has been shown to be the largest driver of food-borne greenhouse gas emissions, water use and land occupation in the US diet. The environmental benefits of substituting animal products with vegetal foods are well documented, but significant psychological barriers persist in reducing meat consumption. Here we use life cycle assessment to appraise the environmental performance of a novel vegetal protein source in the mean US diet where it replaces ground beef, and in vegetarian and vegan diets where it substitutes for legumes, tofu and other protein sources. We find that relative to the mean US diet, vegetarian and vegan diets significantly reduce per-capita food-borne greenhouse gas emission (32% and 67%, respectively, blue water use (70% and 75%, respectively and land occupation (70% and 79%, respectively, primarily in the form of rangeland. The substitution of 10%, 25% and 50% of ground beef with plant-based burger (PBB at the national scale results in substantial reductions in annual US dietary greenhouse gas emissions (4.55-45.42 Mt CO2 equivalents, water consumption (1.30-12.00 km3 and land occupation (22300-190100 km2. Despite PBB's elevated environmental pressures compared to other vegetal protein sources, we demonstrate that minimal risk exists for the disservices of PBB substitution in non-meat diets to outweigh the benefits of ground-beef substitution in the omnivorous American diet. Demand for plant-based oils in PBB production has the potential to increase land use pressures in biodiversity hotspots, though these could be obviated through responsible land stewardship. Although the apparent environmental benefits of the PBB are contingent on actual uptake of the product, this study demonstrates the potential for non-traditional protein substitutes to play a role in a transition towards more sustainable consumption
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Majdoub-Mathlouthi, L; Saïd, B; Kraiem, K
2015-12-01
The objective of this study was to compare carcass and meat quality between Barbarine lambs raised on rangelands and those reared indoors. A total of 24 weaned male lambs (23.2 kg) were allotted into two groups. The first group (GS) grazed pasture dominated by natural shrubs and was supplemented with 100 g of concentrate. The second group (HS) received oat hay and 200 to 300 g supplement of the same concentrate in order to obtain the same average daily gain (ADG) as the GS group. Six lambs from each group were slaughtered. Lambs to be slaughtered were randomly identified at the beginning of the trial. Carcass traits (offals percentage, dressing percentage, cuts yield, tissue composition, fatness and conformation) were determined; pH and meat and fat color were measured. Samples from longissimus lumborum were collected to analyze fatty acid composition. The GS group was characterized by a higher offals percentage, associated with higher lungs, heart, liver and kidney percentage. Carcass dressing percentage defined as the rate between hot carcass weight and empty BW was lower by 3.4% in the GS group. No differences were observed for carcass meat yield and carcass and leg compactness. Shoulder bone percentage of the GS group was higher, without differences in fat and lean percentages. Fat thickness, kidney and tail fats were lower in the GS lambs. However, intramuscular fat content was not affected. Percentages of saturated fatty acids and polyunsaturated fatty acids (PUFA) were not modified, whereas levels of n-3 and long n-3PUFA (EPA, DPA and DHA) as well as Δ5 desaturase plus Δ6 desaturase index were higher for the GS group. Thrombogenic and atherogenic indexes were not altered. No significant effects were observed for meat pH, meat and fat color. Despite having the same ADG, lambs from the GS group were less fatty, and their meat was richer in beneficial fatty acids.
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Forage selection by teddy goats versus sheep on thal ranges
International Nuclear Information System (INIS)
Jasra, A.W.; Hanjra, S.H.
2007-01-01
Grazing behaviours of Teddy goats and Thalli sheep were studied on rangelands of ThaI. Bite count method was used to determine the dietary composition of both animal species. The overall preference of Teddy goats was higher for Khabble grass (Cynodon dactylon), which was 40.57% of the total number of bite made on different plant species during the study period (March-July). Teddy goats utilized a wide range of browsing plant species like Wan (Salvadora oleoides), Phog (Calligonum polygonoides), Babil (Acacia jacquemontii), Jandi (Prosopis spicigera) etc. Browsing species were major component (>50%) of goat diets dur- ing March through June. Whereas Thalli sheep had been consistent in their heavy use of Khabble grass (overall 89.27%). Browsing plant species were not an important component of their diets. Teddy goats and Thalli sheep were competitive for Khabble grass particularly at its vegetative growth stage. (author)
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Patterns of vegetation and grasshopper community composition.
Kemp, W P; Harvey, S J; O'Neill, K M
1990-06-01
A study was conducted to evaluate differences in rangeland grasshopper communities over environmental gradients in Gallatin Valley, Montana, USA. The concept of habitat type (Daubenmire 1966) was used as a basis for discriminating between groupings of patches based on vegetation. A total of 39 patches were selected that represented five recognized grassland habitat types (Mueggler and Stewart 1980), as well as two disturbed types (replanting within a known habitat type). Repeated sampling in 1988 of both the insect and plant communities yielded a total of 40 grasshopper (19 664 individuals) and 97 plant species. Detrended Correspondence Analysis (DCA) indicated that patch classifications based on presence and percent cover of plants were appropriate and showed good between-group (habitat type) separation for patches along gradients of precipitation/elevation and plant community complexity. Results from undisturbed habitats showed that plant and grasshopper species composition changed over observed environmental gradients and suggested that habitat type influenced not only species presence, but also relative abundance. Discussion is presented that relates results with patch-use and core and satellite species paradigms.
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Improving Field-Based Experimental Research to Compliment Contemporary Management
Rangeland management has long been described as both a science and an art (Stoddart et al. 1975). Certainly, the management of rangeland resources, especially during the last half of the 20th century, can be characterized as practices commonly informed by science. There are a number of management...
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The complemental role of dryland cultivated pastures in market ...
African Journals Online (AJOL)
The complemental role of dryland cultivated pastures in market-related beef production from semi-arid rangeland. ... Abstract. Rangeland condition is a decisive factor in determining the income/cost ratio of production hence in the profitability of any beef production enterprise. Cultivated pastures can play an important role in ...
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Determining grazing capacity in Namibia with the aid of remote ...
African Journals Online (AJOL)
The Namibian rangelands consist of a mixture of herbaceous and woody components. The main source of income is from farming systems with grass production the predominant source of forage. For rangeland managers to utilise this source sustainably, the accurate determination of grazing capacity is vital since it allows ...
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Wet thermal accumulation modeling of germination of western U.S. rangeland species
Jennifer K. Rawlins
2009-01-01
The key to stopping high-frequency or catastrophic wildfires in the western U.S. is the successful restoration of burned lands to native plant communities. Developing models of establishment for invasive and native species will help in the selection of species for restoration projects that are able to establish and compete with invasive species given the abiotic...
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Gausman, H. W.; Everitt, J. H.; Escobar, D. E. (Principal Investigator)
1982-01-01
Annual variations in the nitrogen-chlorophyll leaf reflectance of hackberry, honey mesquite and live oak in south Texas, were compared. In spring, leaf reflectance at the 0.55 m wavelength and nitrogen (N) concentration was high but leaf chlorophyll (chl) concentrations were low. In summer, leaf reflectance and N-concentration were low but lead chl concentrations were high. Linear correlations for both spring and summer of leaf reflectance with N and chl concentration or deviations from linear regression were not statistically significant.
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Plant stress signalling: understanding and exploiting plant-plant interactions.
Pickett, J A; Rasmussen, H B; Woodcock, C M; Matthes, M; Napier, J A
2003-02-01
When plants are attacked by insects, volatile chemical signals can be released, not only from the damaged parts, but also systemically from other parts of the plant and this continues after cessation of feeding by the insect. These signals are perceived by olfactory sensory mechanisms in both the herbivorous insects and their parasites. Molecular structures involved can be characterized by means of electrophysiological assays, using the insect sensory system linked to chemical analysis. Evidence is mounting that such signals can also affect neighbouring intact plants, which initiate defence by the induction of further signalling systems, such as those that increase parasitoid foraging. Furthermore, insect electrophysiology can be used in the identification of plant compounds having effects on the plants themselves. It has been found recently that certain plants can release stress signals even when undamaged, and that these can cause defence responses in intact plants. These discoveries provide the basis for new crop protection strategies, that are either delivered by genetic modification of plants or by conventionally produced plants to which the signal is externally applied. Delivery can also be made by means of mixed seed strategies in which the provoking and recipient plants are grown together. Related signalling discoveries within the rhizosphere seem set to extend these approaches into new ways of controlling weeds, by exploiting the elusive potential of allelopathy, but through signalling rather than by direct physiological effects.
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Physical impact of grazing by sheep on the dynamics of Nama ...
African Journals Online (AJOL)
UFS
Physical impact of sheep grazing on arid Karoo subshrub/grass rangeland,. South Africa ... sustainability of rangeland resources, soil and vegetation responses to various grazing systems (Teague &. Dowhower .... The only significant decrease (F3,4 = 18.14, P <0.01) in basal cover of the total herbaceous layer for the 1995 ...
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Moringa oleifera leaf extract: An innovative priming tool for rangeland grasses
NOUMAN, Wasif; SIDDIQUI, Muhammad Tahir; BASRA, Shahzad Maqsood Ahmed
2012-01-01
Moringa oleifera leaf extract (MLE) is rich in amino acids, ascorbate, zeatin, minerals, and many other compounds known for their growth-promoting potential. This study was planned to explore the potential of MLE as a seed priming agent to increase the germination rate and plant vigor of 3 range grasses, i.e. Cenchrus ciliaris, Panicum antidotale, and Echinochloa crusgalli. The priming strategies used were hydropriming, CaCl2, PEG-8000 (-1.1 M Pa), MLE (concentrate; 1:10, 1:20, 1:30, and 1:40...
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Directory of Open Access Journals (Sweden)
Juan Manuel Pinos RodrÃguez
2013-08-01
Full Text Available A community mapping procedure was developed to identify and characterize communal land area used for a traditional goat production system. Participatory cartography indicated that producers have good knowledge of their territory; more than 80% of the spatial distribution and localization of the elements and shapes present in the community map agreed with the map constructed with GIS. All flocks were mainly grazed on communal rangelands where the most important native forage plants were Opuntia spp. Yucca filifera, Condalia mexicana, Dalea spp. and Euphorbia cinerasiens, and corn stover the main crop by-product supplement used during dry season.
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Plant-soil feedbacks: role of plant functional group and plant traits
Cortois, R.; Schröder-Georgi, T.; Weigelt, A.; van der Putten, W.H.; De Deyn, G.B.
2016-01-01
Plant-soil feedback (PSF), plant trait and functional group concepts advanced our understanding of plant community dynamics, but how they are interlinked is poorly known. To test how plant functional groups (FGs: graminoids, small herbs, tall herbs, legumes) and plant traits relate to PSF, we grew
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Munsick, Tristram R; Peck, Dannele E; Ritten, John P; Jones, Randall; Jones, Michelle; Miller, Myrna M
2017-01-01
Recurring outbreaks of bluetongue virus in domestic sheep of the US Intermountain West have prompted questions about the economic benefits and costs of vaccinating individual flocks against bluetongue (BT) disease. We estimate the cost of a BT outbreak on a representative rangeland sheep operation in the Big Horn Basin of the state of Wyoming using enterprise budgets and stochastic simulation. The latter accounts for variability in disease severity and lamb price, as well as uncertainty about when an outbreak will occur. We then estimate the cost of purchasing and administering a BT vaccine. Finally, we calculate expected annual net benefit of vaccinating under various outbreak intervals. Expected annual net benefit is calculated for both a killed virus (KV) vaccine and modified-live virus vaccine, using an observed price of $0.32 per dose for modified-live and an estimated price of $1.20 per dose for KV. The modified-live vaccine's expected annual net benefit has a 100% chance of being positive for an outbreak interval of 5, 10, or 20 years, and a 77% chance of being positive for a 50-year interval. The KV vaccine's expected annual net benefit has a 97% chance of being positive for a 5-year outbreak interval, and a 42% chance of being positive for a 10-year interval. A KV vaccine is, therefore, unlikely to be economically attractive to producers in areas exposed less frequently to BT disease. A modified-live vaccine, however, requires rigorous authorization before legal use can occur in Wyoming. To date, no company has requested to manufacture a modified-live vaccine for commercial use in Wyoming. The KV vaccine poses less risk to sheep reproduction and less risk of unintentional spread, both of which facilitate approval for commercial production. Yet, our results show an economically consequential tradeoff between a KV vaccine's relative safety and higher cost. Unless the purchase price is reduced below our assumed $1.20 per dose, producer adoption of a KV
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LNG plant combined with power plant
Energy Technology Data Exchange (ETDEWEB)
Aoki, I; Kikkawa, Y [Chiyoda Chemical Engineering and Construction Co. Ltd., Tokyo (Japan)
1997-06-01
The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs.
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LNG plant combined with power plant
International Nuclear Information System (INIS)
Aoki, I.; Kikkawa, Y.
1997-01-01
The LNG plant consumers a lot of power of natural gas cooling and liquefaction. In some LNG plant location, a rapid growth of electric power demand is expected due to the modernization of area and/or the country. The electric power demand will have a peak in day time and low consumption in night time, while the power demand of the LNG plant is almost constant due to its nature. Combining the LNG plant with power plant will contribute an improvement the thermal efficiency of the power plant by keeping higher average load of the power plant, which will lead to a reduction of electrical power generation cost. The sweet fuel gas to the power plant can be extracted from the LNG plant, which will be favorable from view point of clean air of the area. (Author). 5 figs
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Future scenarios: a technical document supporting the Forest Service 2010 RPA Assessment
. USDA Forest Service.
2012-01-01
The Forest and Rangeland Renewable Resources Planning Act of 1974 (RPA) mandates a periodic assessment of the conditions and trends of the Nation's renewable resources on forests and rangelands. The RPA Assessment includes projections of resource conditions and trends 50 years into the future. The 2010 RPA Assessment used a set of future scenarios to provide a...
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Resilience of soils and vegetation subjected to different grazing ...
African Journals Online (AJOL)
The resilience of rangeland soils and vegetation to different levels of grazing is still poorly understood. A study was conducted to determine the recovery of a rangeland grazed at different intensities and allowed a two-year rest period. The following treatments were applied to 0.5 hectare plots: 0, 4, 8 and 16 heifers per ...
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Ali, Abdullahi H.; Kauffman, Matthew J.; Amin, Rajan; Kibara, Amos; King, Juliet; Mallon, David P.; Musyoki, Charles; Goheen, Jacob R.
2018-01-01
Effective reintroduction strategies require accurate estimates of vital rates and the factors that influence them. The hirola (Beatragus hunteri) is the rarest antelope on Earth, with a global population size of <500 individuals restricted to the Kenya–Somali border. We estimated vital rates of hirola populations exposed to varying levels of predation and rangeland quality from 2012 to 2015, and then built population matrices to estimate the finite rate of population change (λ) and demographic sensitivities. Mean survival for all age classes and population growth was highest in the low‐predation–high‐rangeland‐quality setting (λ = 1.08 ± 0.03 [mean ± SE]), and lowest in the high‐predation–low‐rangeland‐quality setting (λ = 0.70 ± 0.22). Retrospective demographic analyses revealed that increased fecundity (the number of female calves born to adult females annually) and female calf survival were responsible for higher population growth where large carnivores were absent. In contrast, variation in adult female survival was the primary contributor to differences in population growth attributable to rangeland quality. Our analyses suggest that hirola demography is driven by a combination of top‐down (predation) and bottom‐up (rangeland quality) forces, with populations in the contemporary geographic range impacted both by declining rangeland quality and predation. To enhance the chances of successful reintroductions, conservationists can consider rangeland restoration to boost both the survival and fecundity of adult females within the hirola's historical range.
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Gray, T. I., Jr.; Mccrary, D. G. (Principal Investigator)
1981-01-01
The NOAA-6 AVHRR data sets acquired over South Texas and Mexico during the spring of 1980 and after Hurricane Allen passed inland are analyzed. These data were processed to produce the Gray-McCrary Index (GMI's) for each pixel location over the selected area, which area contained rangeland and cropland, both irrigated and nonirrigated. The variations in the GMI's appear to reflect well the availability of water for vegetation. The GMI area maps are shown to delineate and to aid in defining the duration of drought; suggesting the possibility that time changes over a selected area could be useful for irrigation management.
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Energy Technology Data Exchange (ETDEWEB)
None, None
2016-02-01
The U.S. Department of Energy Office of Legacy Management is evaluating groundwater flow and contaminant transport at a former uranium mill site near Tuba City, Arizona. We estimated effects of temporal and spatial variability in evapotranspiration (ET) on recharge and discharge within a groundwater model domain (GMD) as part of this evaluation. We used remote sensing algorithms and precipitation (PPT) data to estimate ET and the ET/PPT ratios within the 3531 hectare GMD. For the period from 2000 to 2012, ET and PPT were nearly balanced (129 millimeters per year [mm yr-1] and 130 mm yr-1, respectively; ET/PPT = 0.99). However, seasonal and annual variability in ET and PPT were out of phase, and spatial variability in vegetation differentiated discharge and recharge areas within the GMD. Half of ET occurred during spring and early summer when PPT was low, and about 70% of PPT arriving in fall and winter was discharged as plant transpiration in the spring and summer period. Vegetation type and health had a significant effect on the site water balance. Plant cover and ET were significantly higher (1) during years of lighter compared to years of heavier grazing pressure, and (2) on rangeland protected from grazing compared to rangeland grazed by livestock. Heavy grazing increased groundwater recharge (PPT > ET over the 13-year period). Groundwater discharge (ET > PPT over the 13-year period) was highest in riparian phreatophyte communities but insignificant in desert phreatophyte communities impacted by heavy grazing. Grazing management in desert upland and phreatophyte communities may result in reduced groundwater recharge, increased groundwater discharge, and could be used to influence local groundwater flow.
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Plant-plant competition outcomes are modulated by plant effects on the soil bacterial community.
Hortal, S; Lozano, Y M; Bastida, F; Armas, C; Moreno, J L; Garcia, C; Pugnaire, F I
2017-12-19
Competition is a key process that determines plant community structure and dynamics, often mediated by nutrients and water availability. However, the role of soil microorganisms on plant competition, and the links between above- and belowground processes, are not well understood. Here we show that the effects of interspecific plant competition on plant performance are mediated by feedbacks between plants and soil bacterial communities. Each plant species selects a singular community of soil microorganisms in its rhizosphere with a specific species composition, abundance and activity. When two plant species interact, the resulting soil bacterial community matches that of the most competitive plant species, suggesting strong competitive interactions between soil bacterial communities as well. We propose a novel mechanism by which changes in belowground bacterial communities promoted by the most competitive plant species influence plant performance and competition outcome. These findings emphasise the strong links between plant and soil communities, paving the way to a better understanding of plant community dynamics and the effects of soil bacterial communities on ecosystem functioning and services.
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Radioactivity and countermeasures like clean feeding of sheep
International Nuclear Information System (INIS)
2011-01-01
It's been 25 years since the nuclear accident at Chernobyl, but there is still radioactivity remaining in the Norwegian nature. The radioactive cesium-137 is taken up by plants and fungi and transferred to animals on rangelands. In the grazing season of 2010 had 20 000 sheep on Countermeasures like clean feeding to reduce radioactivity levels in the meat before slaughter. Oppland had most sheep on Countermeasures like clean feeding with almost 12 000 animals. Total was paid 2.2 million in compensation to livestock owners in 2010. In the period 1986-2010 is about 2.2 million sheep have been suspended with a charge of approximately NOK 227 million. (AG)
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Apoplastic interactions between plants and plant root intruders
Directory of Open Access Journals (Sweden)
Kanako eMitsumasu
2015-08-01
Full Text Available Numerous pathogenic or parasitic organisms attack plant roots to obtain nutrients, and the apoplast including the plant cell wall is where the plant cell meets such organisms. Root-parasitic angiosperms and nematodes are two distinct types of plant root parasites but share some common features in their strategies for breaking into plant roots. Striga and Orobanche are obligate root parasitic angiosperms that cause devastating agricultural problems worldwide. Parasitic plants form an invasion organ called a haustorium, where plant cell wall degrading enzymes (PCWDEs are highly expressed. Plant-parasitic nematodes are another type of agriculturally important plant root parasite. These nematodes breach the plant cell walls by protruding a sclerotized stylet from which PCWDEs are secreted. Responding to such parasitic invasion, host plants activate their own defense responses against parasites. Endoparasitic nematodes secrete apoplastic effectors to modulate host immune responses and to facilitate the formation of a feeding site. Apoplastic communication between hosts and parasitic plants also contributes to their interaction. Parasitic plant germination stimulants, strigolactones (SLs, are recently identified apoplastic signals that are transmitted over long distances from biosynthetic sites to functioning sites. Here, we discuss recent advances in understanding the importance of apoplastic signals and cell walls for plant-parasite interactions.
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Apoplastic interactions between plants and plant root intruders.
Mitsumasu, Kanako; Seto, Yoshiya; Yoshida, Satoko
2015-01-01
Numerous pathogenic or parasitic organisms attack plant roots to obtain nutrients, and the apoplast including the plant cell wall is where the plant cell meets such organisms. Root parasitic angiosperms and nematodes are two distinct types of plant root parasites but share some common features in their strategies for breaking into plant roots. Striga and Orobanche are obligate root parasitic angiosperms that cause devastating agricultural problems worldwide. Parasitic plants form an invasion organ called a haustorium, where plant cell wall degrading enzymes (PCWDEs) are highly expressed. Plant-parasitic nematodes are another type of agriculturally important plant root parasite. These nematodes breach the plant cell walls by protruding a sclerotized stylet from which PCWDEs are secreted. Responding to such parasitic invasion, host plants activate their own defense responses against parasites. Endoparasitic nematodes secrete apoplastic effectors to modulate host immune responses and to facilitate the formation of a feeding site. Apoplastic communication between hosts and parasitic plants also contributes to their interaction. Parasitic plant germination stimulants, strigolactones, are recently identified apoplastic signals that are transmitted over long distances from biosynthetic sites to functioning sites. Here, we discuss recent advances in understanding the importance of apoplastic signals and cell walls for plant-parasite interactions.
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Tueller, P. T.
1977-01-01
Large scale 70mm aerial photography is a valuable supplementary tool for rangeland studies. A wide assortment of applications were developed varying from vegetation mapping to assessing environmental impact on rangelands. Color and color infrared stereo pairs are useful for effectively sampling sites limited by ground accessibility. They allow an increased sample size at similar or lower cost than ground sampling techniques and provide a permanent record.
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Chemical signaling between plants and plant-pathogenic bacteria.
Venturi, Vittorio; Fuqua, Clay
2013-01-01
Studies of chemical signaling between plants and bacteria in the past have been largely confined to two models: the rhizobial-legume symbiotic association and pathogenesis between agrobacteria and their host plants. Recent studies are beginning to provide evidence that many plant-associated bacteria undergo chemical signaling with the plant host via low-molecular-weight compounds. Plant-produced compounds interact with bacterial regulatory proteins that then affect gene expression. Similarly, bacterial quorum-sensing signals result in a range of functional responses in plants. This review attempts to highlight current knowledge in chemical signaling that takes place between pathogenic bacteria and plants. This chemical communication between plant and bacteria, also referred to as interkingdom signaling, will likely become a major research field in the future, as it allows the design of specific strategies to create plants that are resistant to plant pathogens.
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Directory of Open Access Journals (Sweden)
Joseph O Ogutu
Full Text Available There is growing evidence of escalating wildlife losses worldwide. Extreme wildlife losses have recently been documented for large parts of Africa, including western, Central and Eastern Africa. Here, we report extreme declines in wildlife and contemporaneous increase in livestock numbers in Kenya rangelands between 1977 and 2016. Our analysis uses systematic aerial monitoring survey data collected in rangelands that collectively cover 88% of Kenya's land surface. Our results show that wildlife numbers declined on average by 68% between 1977 and 2016. The magnitude of decline varied among species but was most extreme (72-88% and now severely threatens the population viability and persistence of warthog, lesser kudu, Thomson's gazelle, eland, oryx, topi, hartebeest, impala, Grevy's zebra and waterbuck in Kenya's rangelands. The declines were widespread and occurred in most of the 21 rangeland counties. Likewise to wildlife, cattle numbers decreased (25.2% but numbers of sheep and goats (76.3%, camels (13.1% and donkeys (6.7% evidently increased in the same period. As a result, livestock biomass was 8.1 times greater than that of wildlife in 2011-2013 compared to 3.5 times in 1977-1980. Most of Kenya's wildlife (ca. 30% occurred in Narok County alone. The proportion of the total "national" wildlife population found in each county increased between 1977 and 2016 substantially only in Taita Taveta and Laikipia but marginally in Garissa and Wajir counties, largely reflecting greater wildlife losses elsewhere. The declines raise very grave concerns about the future of wildlife, the effectiveness of wildlife conservation policies, strategies and practices in Kenya. Causes of the wildlife declines include exponential human population growth, increasing livestock numbers, declining rainfall and a striking rise in temperatures but the fundamental cause seems to be policy, institutional and market failures. Accordingly, we thoroughly evaluate wildlife
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Allain, D; Foulquié, D; Autran, P; Francois, D; Bouix, J
2014-01-01
to weather conditions at lambing time in short-woolly lambs, whereas no relation was observed in hairy-coat lambs. Heritability estimate of birthcoat type (hairy or woolly) is high (0.88). Genetic correlations between birthcoat type, lamb survival, and live body weight at birth were positive and moderate, suggesting that it would be beneficial to take birthcoat into account as an adaptive trait in any genetic strategies for sheep production in harsh conditions on rangelands.
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Four planting devices for planting no-till maize
Directory of Open Access Journals (Sweden)
Osei Bonsu Patterson
2015-05-01
Full Text Available An experiment was conducted at the CSIR-Crops Research Institute (CSIR-CRI Experimental station at Ejura in Ghana to compare the efficiency of four devices for planting no-till maize: Tractor drawn seeder, Chinese made jab planter, Locally made jab planter and a Cutlass. It took two (2 hours 48 minutes to plant one hectare of maize with the tractor drawn seeder, which was significantly (p less than 1% faster than all the planting methods. Cutlass was the slowest planting device lasting more than 14 hours per hectare. There was no significant difference in planting time between the Chinese planter and local planter. Economic analysis showed that cutlass planting produced the highest net benefit, whilst tractor drawn seeder produced the least benefit. In this study cutlass planting was done with precision by collaborating farmers. In actual farm situation however, hired laborers (planting gangs often plant in haste which often results in poor plant population leading to low yields. Tractor drawn seeders or jab planters could reduce drudgery in planting and encourage farm expansion.
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Plant aquaporins: roles in plant physiology.
Li, Guowei; Santoni, Véronique; Maurel, Christophe
2014-05-01
Aquaporins are membrane channels that facilitate the transport of water and small neutral molecules across biological membranes of most living organisms. Here, we present comprehensive insights made on plant aquaporins in recent years, pointing to their molecular and physiological specificities with respect to animal or microbial counterparts. In plants, aquaporins occur as multiple isoforms reflecting a high diversity of cellular localizations and various physiological substrates in addition to water. Of particular relevance for plants is the transport by aquaporins of dissolved gases such as carbon dioxide or metalloids such as boric or silicic acid. The mechanisms that determine the gating and subcellular localization of plant aquaporins are extensively studied. They allow aquaporin regulation in response to multiple environmental and hormonal stimuli. Thus, aquaporins play key roles in hydraulic regulation and nutrient transport in roots and leaves. They contribute to several plant growth and developmental processes such as seed germination or emergence of lateral roots. Plants with genetically altered aquaporin functions are now tested for their ability to improve plant resistance to stresses. This article is part of a Special Issue entitled Aquaporins. Copyright © 2013 Elsevier B.V. All rights reserved.
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Integrated Gasification SOFC Plant with a Steam Plant
DEFF Research Database (Denmark)
Rokni, Masoud; Pierobon, Leonardo
2011-01-01
A hybrid Solid Oxide Fuel Cell (SOFC) and Steam Turbine (ST) plant is integrated with a gasification plant. Wood chips are fed to the gasification plant to produce biogas and then this gas is fed into the anode side of a SOFC cycle to produce electricity and heat. The gases from the SOFC stacks...... enter into a burner to burn the rest of the fuel. The offgases after the burner are now used to generate steam in a Heat Recovery Steam Generator (HRSG). The generated steam is expanded in a ST to produce additional power. Thus a triple hybrid plant based on a gasification plant, a SOFC plant...... and a steam plant is presented and studied. The plant is called as IGSS (Integrated Gasification SOFC Steam plant). Different systems layouts are presented and investigated. Electrical efficiencies up to 56% are achieved which is considerably higher than the conventional integrated gasification combined...
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Tarkowská, Danuše; Strnad, Miroslav
2016-09-01
The present review summarises current knowledge of phytoecdysteroids' biosynthesis, distribution within plants, biological importance and relations to plant hormones. Plant ecdysteroids (phytoecdysteroids) are natural polyhydroxylated compounds that have a four-ringed skeleton, usually composed of either 27 carbon atoms or 28-29 carbon atoms (biosynthetically derived from cholesterol or other plant sterols, respectively). Their physiological roles in plants have not yet been confirmed and their occurrence is not universal. Nevertheless, they are present at high concentrations in various plant species, including commonly consumed vegetables, and have a broad spectrum of pharmacological and medicinal properties in mammals, including hepatoprotective and hypoglycaemic effects, and anabolic effects on skeletal muscle, without androgenic side-effects. Furthermore, phytoecdysteroids can enhance stress resistance by promoting vitality and enhancing physical performance; thus, they are considered adaptogens. This review summarises current knowledge of phytoecdysteroids' biosynthesis, distribution within plants, biological importance and relations to plant hormones.
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Plant toxicity, adaptive herbivory, and plant community dynamics
Feng, Z.; Liu, R.; DeAngelis, D.L.; Bryant, J.P.; Kielland, K.; Stuart, Chapin F.; Swihart, R.K.
2009-01-01
We model effects of interspecific plant competition, herbivory, and a plant's toxic defenses against herbivores on vegetation dynamics. The model predicts that, when a generalist herbivore feeds in the absence of plant toxins, adaptive foraging generally increases the probability of coexistence of plant species populations, because the herbivore switches more of its effort to whichever plant species is more common and accessible. In contrast, toxin-determined selective herbivory can drive plant succession toward dominance by the more toxic species, as previously documented in boreal forests and prairies. When the toxin concentrations in different plant species are similar, but species have different toxins with nonadditive effects, herbivores tend to diversify foraging efforts to avoid high intakes of any one toxin. This diversification leads the herbivore to focus more feeding on the less common plant species. Thus, uncommon plants may experience depensatory mortality from herbivory, reducing local species diversity. The depensatory effect of herbivory may inhibit the invasion of other plant species that are more palatable or have different toxins. These predictions were tested and confirmed in the Alaskan boreal forest. ?? 2009 Springer Science+Business Media, LLC.
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Vulnerability of social-ecological system to climate change in Mongolia
Kakinuma, K.; Yanagawa, A.; Sasaki, T.; Kanae, S.
2017-12-01
Coping with future climate changes are one of the most important issues in the world. IPCC (2014) suggested that vulnerability and exposure of social-ecological systems to extreme climatic events (hazard) determine the impact of climate changes. Although the schematic framework is widely accepted, there are high uncertainty of vulnerability of social and ecological systems and it makes difficult to examine it in empirical researches. Our objective is to assess the climate change impact on the social-ecological system in Mongolia. We review researches about trends of climate (Hazard), vegetation, pastoral mobility (Vulnerability) and livestock distribution (Exposure) across Mongolia Climate trends are critical for last several decades and thus hazard may be increasing in Mongolia. Temperature is increasing with high confidence in all regions. Precipitation are slightly decreasing with medium confidence across the country, especially in northern and central regions. Exposure would also be increasing especially in northern, central and western regions, because livestock population are concentrating these regions after 1990. Generally, less productive ecosystems (e.g. few plant productivity and less species richness) are vulnerable to extreme climatic events such as drought. In that sense, southern region may be more vulnerable to climate changes than other regions. However, if we focus on pastoral mobility forms for drought, we get contractive conclusions. Pastoralists in southern region keep mobility to variable and scarce vegetation while pastoralists in northern region less mobile because of stable and much vegetation. Exclusive managements in northern region is able to maximized the number of livestock only under stable precipitation regimes. But at the same time, it is difficult to escape from hazardous areas when it is drought. Thus, in term of rangeland management, northern region would be more vulnerable to increase of drought intensity. Although northern and
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[Development of Plant Metabolomics and Medicinal Plant Genomics].
Saito, Kazuki
2018-01-01
A variety of chemicals produced by plants, often referred to as 'phytochemicals', have been used as medicines, food, fuels and industrial raw materials. Recent advances in the study of genomics and metabolomics in plant science have accelerated our understanding of the mechanisms, regulation and evolution of the biosynthesis of specialized plant products. We can now address such questions as how the metabolomic diversity of plants is originated at the levels of genome, and how we should apply this knowledge to drug discovery, industry and agriculture. Our research group has focused on metabolomics-based functional genomics over the last 15 years and we have developed a new research area called 'Phytochemical Genomics'. In this review, the development of a research platform for plant metabolomics is discussed first, to provide a better understanding of the chemical diversity of plants. Then, representative applications of metabolomics to functional genomics in a model plant, Arabidopsis thaliana, are described. The extension of integrated multi-omics analyses to non-model specialized plants, e.g., medicinal plants, is presented, including the identification of novel genes, metabolites and networks for the biosynthesis of flavonoids, alkaloids, sulfur-containing metabolites and terpenoids. Further, functional genomics studies on a variety of medicinal plants is presented. I also discuss future trends in pharmacognosy and related sciences.
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7 CFR 302.2 - Movement of plants and plant products.
2010-01-01
... 7 Agriculture 5 2010-01-01 2010-01-01 false Movement of plants and plant products. 302.2 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DISTRICT OF COLUMBIA; MOVEMENT OF PLANTS AND PLANT PRODUCTS § 302.2 Movement of plants and plant products. Inspection or documentation of the plant health status of...
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PLANT BIOPRINTING: NOVEL PERSPECTIVE FOR PLANT BIOTECHNOLOGY
Directory of Open Access Journals (Sweden)
Adhityo WICAKSONO
2015-12-01
Full Text Available Bioprinting is a technical innovation that has revolutionized tissue engineering. Using conventional printer cartridges filled with cells as well as a suitable scaffold, major advances have been made in the biomedical field, and it is now possible to print skin, bones, blood vessels, and even organs. Unlike animal systems, the application of bioprinting in simple plant tissue cells is still in a nascent phase and has yet to be studied. One major advantage of plants is that all living parts are reprogrammable in the form of totipotent cells. Plant bioprinting may improve scientists’understanding of plant shape and morphogenesis, and could serve for the mass production of desired tissues or plants, or even the production of plant-based biomaterial for industrial uses. This perspectives paper explores these possibilities using knowledge on what is known about bioprinting in other biosystems.
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Plant responses to plant growth-promoting rhizobacteria
Loon, L.C. van
2007-01-01
Non-pathogenic soilborne microorganisms can promote plant growth, as well as suppress diseases. Plant growth promotion is taken to result from improved nutrient acquisition or hormonal stimulation. Disease suppression can occur through microbial antagonism or induction of resistance in the plant.
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The iPlant Collaborative: Cyberinfrastructure for Plant Biology
Goff, Stephen A.; Vaughn, Matthew; McKay, Sheldon; Lyons, Eric; Stapleton, Ann E.; Gessler, Damian; Matasci, Naim; Wang, Liya; Hanlon, Matthew; Lenards, Andrew; Muir, Andy; Merchant, Nirav; Lowry, Sonya; Mock, Stephen; Helmke, Matthew; Kubach, Adam; Narro, Martha; Hopkins, Nicole; Micklos, David; Hilgert, Uwe; Gonzales, Michael; Jordan, Chris; Skidmore, Edwin; Dooley, Rion; Cazes, John; McLay, Robert; Lu, Zhenyuan; Pasternak, Shiran; Koesterke, Lars; Piel, William H.; Grene, Ruth; Noutsos, Christos; Gendler, Karla; Feng, Xin; Tang, Chunlao; Lent, Monica; Kim, Seung-Jin; Kvilekval, Kristian; Manjunath, B. S.; Tannen, Val; Stamatakis, Alexandros; Sanderson, Michael; Welch, Stephen M.; Cranston, Karen A.; Soltis, Pamela; Soltis, Doug; O'Meara, Brian; Ane, Cecile; Brutnell, Tom; Kleibenstein, Daniel J.; White, Jeffery W.; Leebens-Mack, James; Donoghue, Michael J.; Spalding, Edgar P.; Vision, Todd J.; Myers, Christopher R.; Lowenthal, David; Enquist, Brian J.; Boyle, Brad; Akoglu, Ali; Andrews, Greg; Ram, Sudha; Ware, Doreen; Stein, Lincoln; Stanzione, Dan
2011-01-01
The iPlant Collaborative (iPlant) is a United States National Science Foundation (NSF) funded project that aims to create an innovative, comprehensive, and foundational cyberinfrastructure in support of plant biology research (PSCIC, 2006). iPlant is developing cyberinfrastructure that uniquely enables scientists throughout the diverse fields that comprise plant biology to address Grand Challenges in new ways, to stimulate and facilitate cross-disciplinary research, to promote biology and computer science research interactions, and to train the next generation of scientists on the use of cyberinfrastructure in research and education. Meeting humanity's projected demands for agricultural and forest products and the expectation that natural ecosystems be managed sustainably will require synergies from the application of information technologies. The iPlant cyberinfrastructure design is based on an unprecedented period of research community input, and leverages developments in high-performance computing, data storage, and cyberinfrastructure for the physical sciences. iPlant is an open-source project with application programming interfaces that allow the community to extend the infrastructure to meet its needs. iPlant is sponsoring community-driven workshops addressing specific scientific questions via analysis tool integration and hypothesis testing. These workshops teach researchers how to add bioinformatics tools and/or datasets into the iPlant cyberinfrastructure enabling plant scientists to perform complex analyses on large datasets without the need to master the command-line or high-performance computational services. PMID:22645531
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The iPlant Collaborative: Cyberinfrastructure for Plant Biology.
Goff, Stephen A; Vaughn, Matthew; McKay, Sheldon; Lyons, Eric; Stapleton, Ann E; Gessler, Damian; Matasci, Naim; Wang, Liya; Hanlon, Matthew; Lenards, Andrew; Muir, Andy; Merchant, Nirav; Lowry, Sonya; Mock, Stephen; Helmke, Matthew; Kubach, Adam; Narro, Martha; Hopkins, Nicole; Micklos, David; Hilgert, Uwe; Gonzales, Michael; Jordan, Chris; Skidmore, Edwin; Dooley, Rion; Cazes, John; McLay, Robert; Lu, Zhenyuan; Pasternak, Shiran; Koesterke, Lars; Piel, William H; Grene, Ruth; Noutsos, Christos; Gendler, Karla; Feng, Xin; Tang, Chunlao; Lent, Monica; Kim, Seung-Jin; Kvilekval, Kristian; Manjunath, B S; Tannen, Val; Stamatakis, Alexandros; Sanderson, Michael; Welch, Stephen M; Cranston, Karen A; Soltis, Pamela; Soltis, Doug; O'Meara, Brian; Ane, Cecile; Brutnell, Tom; Kleibenstein, Daniel J; White, Jeffery W; Leebens-Mack, James; Donoghue, Michael J; Spalding, Edgar P; Vision, Todd J; Myers, Christopher R; Lowenthal, David; Enquist, Brian J; Boyle, Brad; Akoglu, Ali; Andrews, Greg; Ram, Sudha; Ware, Doreen; Stein, Lincoln; Stanzione, Dan
2011-01-01
The iPlant Collaborative (iPlant) is a United States National Science Foundation (NSF) funded project that aims to create an innovative, comprehensive, and foundational cyberinfrastructure in support of plant biology research (PSCIC, 2006). iPlant is developing cyberinfrastructure that uniquely enables scientists throughout the diverse fields that comprise plant biology to address Grand Challenges in new ways, to stimulate and facilitate cross-disciplinary research, to promote biology and computer science research interactions, and to train the next generation of scientists on the use of cyberinfrastructure in research and education. Meeting humanity's projected demands for agricultural and forest products and the expectation that natural ecosystems be managed sustainably will require synergies from the application of information technologies. The iPlant cyberinfrastructure design is based on an unprecedented period of research community input, and leverages developments in high-performance computing, data storage, and cyberinfrastructure for the physical sciences. iPlant is an open-source project with application programming interfaces that allow the community to extend the infrastructure to meet its needs. iPlant is sponsoring community-driven workshops addressing specific scientific questions via analysis tool integration and hypothesis testing. These workshops teach researchers how to add bioinformatics tools and/or datasets into the iPlant cyberinfrastructure enabling plant scientists to perform complex analyses on large datasets without the need to master the command-line or high-performance computational services.
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The iPlant Collaborative: Cyberinfrastructure for Plant Biology
Directory of Open Access Journals (Sweden)
Stephen A Goff
2011-07-01
Full Text Available The iPlant Collaborative (iPlant is a United States National Science Foundation (NSF funded project that aims to create an innovative, comprehensive, and foundational cyberinfrastructure in support of plant biology research (PSCIC, 2006. iPlant is developing cyberinfrastructure that uniquely enables scientists throughout the diverse fields that comprise plant biology to address Grand Challenges in new ways, to stimulate and facilitate cross-disciplinary research, to promote biology and computer science research interactions, and to train the next generation of scientists on the use of cyberinfrastructure in research and education. Meeting humanity's projected demands for agricultural and forest products and the expectation that natural ecosystems be managed sustainably will require synergies from the application of information technologies. The iPlant cyberinfrastructure design is based on an unprecedented period of research community input, and leverages developments in high-performance computing, data storage, and cyberinfrastructure for the physical sciences. iPlant is an open-source project with application programming interfaces that allow the community to extend the infrastructure to meet its needs. iPlant is sponsoring community-driven workshops addressing specific scientific questions via analysis tool integration and hypothesis testing. These workshops teach researchers how to add bioinformatics tools and/or datasets into the iPlant cyberinfrastructure enabling plant scientists to perform complex analyses on large datasets without the need to master the command-line or high-performance computational services.
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Aboveground mechanical stimuli affect belowground plant-plant communication.
Elhakeem, Ali; Markovic, Dimitrije; Broberg, Anders; Anten, Niels P R; Ninkovic, Velemir
2018-01-01
Plants can detect the presence of their neighbours and modify their growth behaviour accordingly. But the extent to which this neighbour detection is mediated by abiotic stressors is not well known. In this study we tested the acclimation response of Zea mays L. seedlings through belowground interactions to the presence of their siblings exposed to brief mechano stimuli. Maize seedling simultaneously shared the growth solution of touched plants or they were transferred to the growth solution of previously touched plants. We tested the growth preferences of newly germinated seedlings toward the growth solution of touched (T_solution) or untouched plants (C_solution). The primary root of the newly germinated seedlings grew significantly less towards T_solution than to C_solution. Plants transferred to T_solution allocated more biomass to shoots and less to roots. While plants that simultaneously shared their growth solution with the touched plants produced more biomass. Results show that plant responses to neighbours can be modified by aboveground abiotic stress to those neighbours and suggest that these modifications are mediated by belowground interactions.
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Aboveground mechanical stimuli affect belowground plant-plant communication.
Directory of Open Access Journals (Sweden)
Ali Elhakeem
Full Text Available Plants can detect the presence of their neighbours and modify their growth behaviour accordingly. But the extent to which this neighbour detection is mediated by abiotic stressors is not well known. In this study we tested the acclimation response of Zea mays L. seedlings through belowground interactions to the presence of their siblings exposed to brief mechano stimuli. Maize seedling simultaneously shared the growth solution of touched plants or they were transferred to the growth solution of previously touched plants. We tested the growth preferences of newly germinated seedlings toward the growth solution of touched (T_solution or untouched plants (C_solution. The primary root of the newly germinated seedlings grew significantly less towards T_solution than to C_solution. Plants transferred to T_solution allocated more biomass to shoots and less to roots. While plants that simultaneously shared their growth solution with the touched plants produced more biomass. Results show that plant responses to neighbours can be modified by aboveground abiotic stress to those neighbours and suggest that these modifications are mediated by belowground interactions.
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Notter, D R; Mousel, M R; Lewis, G S; Leymaster, K A; Taylor, J B
2017-09-01
Ewe productivity (i.e., total number or weight of lambs weaned per breeding ewe) is a key indicator of lamb production efficiency. This study compared various measures of ewe productivity and ewe and lamb performance among ewes of 3 breed types mated to rams of 4 terminal-sire breed types in an extensive rangeland production system. Purebred Rambouillet ( = 212), purebred Polypay ( = 236), and crossbred Romanov-White Dorper × Rambouillet (RW-RA; = 231) ewes were produced from locally adapted Polypay and Rambouillet ewes and then annually mated to Columbia, Suffolk, Columbia × Suffolk, or Suffolk × Columbia sires for up to 4 yr, beginning at 1 yr of age. The cumulative number and weight of lambs weaned through 4 yr were greater for RW-RA (5.9 lambs and 153 kg, respectively) and Polypay ewes (4.9 lambs and 123 kg, respectively) than for Rambouillet ewes (2.9 lambs and 99 kg, respectively) and also were greater for RW-RA ewes than for Polypay ewes (all ewes, compared with Rambouillet ewes, was driven by greater lambing rates (ewes lambing per ewe exposed) as ewe lambs (87 and 77 vs. 31%, respectively; ewe lambs (1.3, 1.3, and 1.0, respectively) and adult ewes (2.1, 2.0, and 1.6, respectively). The RW-RA ewes also had greater longevity ( ewes. Lamb BW at birth and weaning in adult ewes favored less-prolific Rambouillet ewes ( ewe breed types were small and not significant ( = 0.08). Effects of sire breed type on measures of cumulative ewe productivity were not significant ( > 0.74), but Suffolk-sired lambs had the heaviest adjusted birth weights ( = 0.01) and Columbia-sired lambs tended to have the lightest adjusted weaning weights ( = 0.12). Combined effects of heterosis and additive breed effects were associated with greater lambing rates in ewe lambs, larger litters at all ages, and substantially greater number and weight of lambs weaned for Polypay and RW-RA ewes than for Rambouillet ewes.
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Ogutu, Joseph O.; Piepho, Hans-Peter; Said, Mohamed Y.; Ojwang, Gordon O.; Njino, Lucy W.; Kifugo, Shem C.; Wargute, Patrick W.
2016-01-01
There is growing evidence of escalating wildlife losses worldwide. Extreme wildlife losses have recently been documented for large parts of Africa, including western, Central and Eastern Africa. Here, we report extreme declines in wildlife and contemporaneous increase in livestock numbers in Kenya rangelands between 1977 and 2016. Our analysis uses systematic aerial monitoring survey data collected in rangelands that collectively cover 88% of Kenya’s land surface. Our results show that wildlife numbers declined on average by 68% between 1977 and 2016. The magnitude of decline varied among species but was most extreme (72–88%) and now severely threatens the population viability and persistence of warthog, lesser kudu, Thomson’s gazelle, eland, oryx, topi, hartebeest, impala, Grevy’s zebra and waterbuck in Kenya’s rangelands. The declines were widespread and occurred in most of the 21 rangeland counties. Likewise to wildlife, cattle numbers decreased (25.2%) but numbers of sheep and goats (76.3%), camels (13.1%) and donkeys (6.7%) evidently increased in the same period. As a result, livestock biomass was 8.1 times greater than that of wildlife in 2011–2013 compared to 3.5 times in 1977–1980. Most of Kenya’s wildlife (ca. 30%) occurred in Narok County alone. The proportion of the total “national” wildlife population found in each county increased between 1977 and 2016 substantially only in Taita Taveta and Laikipia but marginally in Garissa and Wajir counties, largely reflecting greater wildlife losses elsewhere. The declines raise very grave concerns about the future of wildlife, the effectiveness of wildlife conservation policies, strategies and practices in Kenya. Causes of the wildlife declines include exponential human population growth, increasing livestock numbers, declining rainfall and a striking rise in temperatures but the fundamental cause seems to be policy, institutional and market failures. Accordingly, we thoroughly evaluate
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Weir, Tiffany L; Bais, Harsh Pal; Vivanco, Jorge M
2003-11-01
Centarea maculosa Lam. (spotted knapweed) is one of the most destructive invasive weeds in the western United States, particularly in pastures and rangelands. One of the components that may contribute to its invasiveness is the naturally produced, root-secreted allelochemical (-)-catechin. This compound has been shown to have broad-spectrum phytotoxic activity, possibly assisting C. maculosa in displacing native plant communities. As a recently characterized phytochemical, little is known about the specific effect of (-)-catechin on either C. maculosa or other plant species. We have found that, in vitro, C. maculosa begins to secrete phytotoxic levels of (-)-catechin within 2-3 weeks of seedling emergence. Furthermore, (-)-catechin concentrations consistent with those naturally secreted by C. maculosa were sufficient to inhibit germination in all species tested, including C. maculosa. These concentrations were also often either phytotoxic or growth inhibitory to seedlings in a range of plant species, while having no negative effects on the growth of C. maculosa seedlings. However, our results also indicate that different levels of resistance and susceptibility to (-)-catechin exist in plant populations, suggesting that the capability of C. maculosa to invade an area through allelochemistry may be dependent on the age and species composition of plants in that area.
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Design of plant safety model in plant enterprise engineering environment
International Nuclear Information System (INIS)
Gabbar, Hossam A.; Suzuki, Kazuhiko; Shimada, Yukiyasu
2001-01-01
Plant enterprise engineering environment (PEEE) is an approach aiming to manage the plant through its lifecycle. In such environment, safety is considered as the common objective for all activities throughout the plant lifecycle. One approach to achieve plant safety is to embed safety aspects within each function and activity within such environment. One ideal way to enable safety aspects within each automated function is through modeling. This paper proposes a theoretical approach to design plant safety model as integrated with the plant lifecycle model within such environment. Object-oriented modeling approach is used to construct the plant safety model using OO CASE tool on the basis of unified modeling language (UML). Multiple views are defined for plant objects to express static, dynamic, and functional semantics of these objects. Process safety aspects are mapped to each model element and inherited from design to operation stage, as it is naturally embedded within plant's objects. By developing and realizing the plant safety model, safer plant operation can be achieved and plant safety can be assured
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DEFF Research Database (Denmark)
Madsen, T. V.; Sand-Jensen, K.
2006-01-01
Aquatic fl owering plants form a relatively young plant group on an evolutionary timescale. The group has developed over the past 80 million years from terrestrial fl owering plants that re-colonised the aquatic environment after 60-100 million years on land. The exchange of species between terre...... terrestrial and aquatic environments continues today and is very intensive along stream banks. In this chapter we describe the physical and chemical barriers to the exchange of plants between land and water.......Aquatic fl owering plants form a relatively young plant group on an evolutionary timescale. The group has developed over the past 80 million years from terrestrial fl owering plants that re-colonised the aquatic environment after 60-100 million years on land. The exchange of species between...
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Plants, plant pathogens, and microgravity--a deadly trio
Leach, J. E.; Ryba-White, M.; Sun, Q.; Wu, C. J.; Hilaire, E.; Gartner, C.; Nedukha, O.; Kordyum, E.; Keck, M.; Leung, H.;
2001-01-01
Plants grown in spaceflight conditions are more susceptible to colonization by plant pathogens. The underlying causes for this enhanced susceptibility are not known. Possibly the formation of structural barriers and the activation of plant defense response components are impaired in spaceflight conditions. Either condition would result from altered gene expression of the plant. Because of the tools available, past studies focused on a few physiological responses or biochemical pathways. With recent advances in genomics research, new tools, including microarray technologies, are available to examine the global impact of growth in the spacecraft on the plant's gene expression profile. In ground-based studies, we have developed cDNA subtraction libraries of rice that are enriched for genes induced during pathogen infection and the defense response. Arrays of these genes are being used to dissect plant defense response pathways in a model system involving wild-type rice plants and lesion mimic mutants. The lesion mimic mutants are ideal experimental tools because they erratically develop defense response-like lesions in the absence of pathogens. The gene expression profiles from these ground-based studies will provide the molecular basis for understanding the biochemical and physiological impacts of spaceflight on plant growth, development and disease defense responses. This, in turn, will allow the development of strategies to manage plant disease for life in the space environment.
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Plant life management optimized utilization of existing nuclear power plants
International Nuclear Information System (INIS)
Watzinger, H.; Erve, M.
1999-01-01
For safe, reliable and economical nuclear power generation it is of central importance to understand, analyze and manage aging-related phenomena and to apply this information in the systematic utilization and as-necessary extension of the service life of components and systems. An operator's overall approach to aging and plant life management which also improves performance characteristics can help to optimize plant operating economy. In view of the deregulation of the power generation industry with its increased competition, nuclear power plants must today also increasingly provide for or maintain a high level of plant availability and low power generating costs. This is a difficult challenge even for the newest, most modern plants, and as plants age they can only remain competitive if a plant operator adopts a strategic approach which takes into account the various aging-related effects on a plant-wide basis. The significance of aging and plant life management for nuclear power plants becomes apparent when looking at their age: By the year 2000 roughly fifty of the world's 434 commercial nuclear power plants will have been in operation for thirty years or more. According to the International Atomic Energy Agency, as many as 110 plants will have reached the thirty-year service mark by the year 2005. In many countries human society does not push the construction of new nuclear power plants and presumably will not change mind within the next ten years. New construction licenses cannot be expected so that for economical and ecological reasons existing plants have to be operated unchallengeably. On the other hand the deregulation of the power production market is asking just now for analysis of plant life time to operate the plants at a high technical and economical level until new nuclear power plants can be licensed and constructed. (author)
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Jankju, M; Maghamnia, A
2010-07-01
Plant-plant interactions are known as the main biotic drivers of the vegetation dynamics. Therefore, understanding such processes is beneficial for the applied vegetation management. The aim of this research was to investigate the type and intensity of plant-plant interaction during the time course of a growth season. We studied ecophysiological aspects of facilitation and competition between two aridland shrubs, A. meschedensis Bunge and A. raddeanam Czernjak and one perennial grass, B. kopetdaghensis Krasch. Soil and plant sampling were carried out for shrubs and the grass that were either growing alone or the grass was growing under the canopy of shrubs. In Spring (May), soil humidity weight was higher under the shrubs+grass than the grass-only site. By the beginning of Summer (July) grass consumed the common soil water and rapidly terminated its yearly growth. Therefore, in August and September, soil humidity weight was lower under the shrubs+grass than shrub-only sites. Photosynthesis rate of B. kopetdaghensis was sharply reduced from the beginning towards the end of growth season, but was not varied between the different plant combinations. Leaf proline measurement in July indicated higher stress for B. kopetdaghensis that were growing under shrubs than those of open areas. In conclusion, we found facilitation effects of shrubs on the grass at the early times of growth season, but it shifted into the competition for water during summer times. The outcome of plant interaction was positive for the grass but negative for the shrubs, especially A. meschedensis.
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Dipping Strawberry Plants in Fungicides before Planting to Control Anthracnose
Directory of Open Access Journals (Sweden)
Myeong Hyeon Nam
2014-03-01
Full Text Available Anthracnose crown rot (ACR, caused by Colletotrichum fructicola, is a serious disease of strawberry in Korea. The primary inoculums of ACR were symptomless strawberry plants, plant debris, and other host plants. To effectively control anthracnose in symptomless transplanted strawberries, it is necessary to use diseasefree plants, detect the disease early, and apply a fungicide. Therefore, in 2010 and 2011, we evaluated the efficacy of pre-plant fungicide dips by using strawberry transplants infected by C. fructicola for the control of anthracnose. Dipping plants in prochloraz-Mn for 10 min before planting was most effective for controlling anthracnose in symptomless strawberry plants and resulted in more than 76% control efficacy. Azoxystrobin showed a control efficacy of over 40%, but plants treated with pyraclostrobin, mancozeb and iminoctadine tris showed high disease severity. The control efficacy of the dip treatment with prochloraz-Mn did not differ with temperature and time. Treatment with prochloraz-Mn for more than an hour caused growth suppression in strawberry plants. Therefore, the development of anthracnose can be effectively reduced by dipping strawberry plants for 10 min in prochloraz-Mn before planting.
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Plant traits related to nitrogen uptake influence plant-microbe competition.
Moreau, Delphine; Pivato, Barbara; Bru, David; Busset, Hugues; Deau, Florence; Faivre, Céline; Matejicek, Annick; Strbik, Florence; Philippot, Laurent; Mougel, Christophe
2015-08-01
Plant species are important drivers of soil microbial communities. However, how plant functional traits are shaping these communities has received less attention though linking plant and microbial traits is crucial for better understanding plant-microbe interactions. Our objective was to determine how plant-microbe interactions were affected by plant traits. Specifically we analyzed how interactions between plant species and microbes involved in nitrogen cycling were affected by plant traits related to 'nitrogen nutrition in interaction with soil nitrogen availability. Eleven plant species, selected along an oligotrophic-nitrophilic gradient, were grown individually in a nitrogen-poor soil with two levels of nitrate availability. Plant traits for both carbon and nitrogen nutrition were measured and the genetic structure and abundance of rhizosphere. microbial communities, in particular the ammonia oxidizer and nitrate reducer guilds, were analyzed. The structure of the bacterial community in the rhizosphere differed significantly between plant species and these differences depended on nitrogen availability. The results suggest that the rate of nitrogen uptake per unit of root biomass and per day is a key plant trait, explaining why the effect of nitrogen availability on the structure of the bacterial community depends on the plant species. We also showed that the abundance of nitrate reducing bacteria always decreased with increasing nitrogen uptake per unit of root biomass per day, indicating that there was competition for nitrate between plants and nitrate reducing bacteria. This study demonstrates that nitrate-reducing microorganisms may be adversely affected by plants with a high nitrogen uptake rate. Our work puts forward the role of traits related to nitrogen in plant-microbe interactions, whereas carbon is commonly considered as the main driver. It also suggests that plant traits related to ecophysiological processes, such as nitrogen uptake rates, are more
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International Nuclear Information System (INIS)
Preuss, W.; Kramer, J.; Wildberg, D.
1987-01-01
The necessary qualifications of the responsible personnel and the knowledge required by personnel otherwise employed in nuclear plants are among the requirements for licensing laid down in paragraph 7 of the German Atomic Energy Act. The formal regulations for nuclear power plants are not directly applicable to plants in the fuel cycle because of the differences in the technical processes and the plant and work organisation. The aim of the project was therefore to establish a possible need for regulations for the nuclear plants with respect to the qualification of the personnel, and to determine a starting point for the definition of the required qualifications. An extensive investigation was carried out in the Federal Republic of Germany into: the formal requirements for training; the plant and personnel organisation structures; the tasks carried out by the responsible and otherwise employed personnel; and the state of training. For this purpose plant owners and managers were interviewed and the literature and plant specific documentation (e.g. plant rules) were reviewed. On the basis of literature research, foreign practices were determined and used to make comparative evaluations. The status report is divided into three separate parts for the reprocessing, the uranium enrichment, and the manufacture of the fuel elements. On the basis of the situation for reprocessing plants (particularly that of the WAK) and fuel element manufacturing plants, the development of a common (not uniform) regulation for all the examined plants in the fuel cycle was recommended. The report gives concrete suggestions for the content of the regulations. (orig.) [de
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Conservation law of plants' energy value dependence of plants ...
African Journals Online (AJOL)
The plants differences in biochemical composition are analyzed, and the conservation law of energy value in plants is obtained. The link between the need for the nutrients and the plants biochemical composition is examined, Liebig's law is specified. Keywords: plant's biochemical composition, biochemistry, energy value in ...
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An Automated and Continuous Plant Weight Measurement System for Plant Factory.
Chen, Wei-Tai; Yeh, Yu-Hui F; Liu, Ting-Yu; Lin, Ta-Te
2016-01-01
In plant factories, plants are usually cultivated in nutrient solution under a controllable environment. Plant quality and growth are closely monitored and precisely controlled. For plant growth evaluation, plant weight is an important and commonly used indicator. Traditional plant weight measurements are destructive and laborious. In order to measure and record the plant weight during plant growth, an automated measurement system was designed and developed herein. The weight measurement system comprises a weight measurement device and an imaging system. The weight measurement device consists of a top disk, a bottom disk, a plant holder and a load cell. The load cell with a resolution of 0.1 g converts the plant weight on the plant holder disk to an analog electrical signal for a precise measurement. The top disk and bottom disk are designed to be durable for different plant sizes, so plant weight can be measured continuously throughout the whole growth period, without hindering plant growth. The results show that plant weights measured by the weight measurement device are highly correlated with the weights estimated by the stereo-vision imaging system; hence, plant weight can be measured by either method. The weight growth of selected vegetables growing in the National Taiwan University plant factory were monitored and measured using our automated plant growth weight measurement system. The experimental results demonstrate the functionality, stability and durability of this system. The information gathered by this weight system can be valuable and beneficial for hydroponic plants monitoring research and agricultural research applications.
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An Automated and Continuous Plant Weight Measurement System for Plant Factory
Directory of Open Access Journals (Sweden)
Wei-Tai eChen
2016-03-01
Full Text Available In plant factories, plants are usually cultivated in nutrient solution under a controllable environment. Plant quality and growth are closely monitored and precisely controlled. For plant growth evaluation, plant weight is an important and commonly used indicator. Traditional plant weight measurements are destructive and laborious. In order to measure and record the plant weight during plant growth, an automated measurement system was designed and developed herein. The weight measurement system comprises a weight measurement device and an imaging system. The weight measurement device consists of a top disk, a bottom disk, a plant holder and a load cell. The load cell with a resolution of 0.1 g converts the plant weight on the plant holder disk to an analogue electrical signal for a precise measurement. The top disk and bottom disk are designed to be durable for different plant sizes, so plant weight can be measured continuously throughout the whole growth period, without hindering plant growth. The results show that plant weights measured by the weight measurement device are highly correlated with the weights estimated by the stereo-vision imaging system; hence, plant weight can be measured by either method. The weight growth of selected vegetables growing in the National Taiwan University plant factory were monitored and measured using our automated plant growth weight measurement system. The experimental results demonstrate the functionality, stability and durability of this system. The information gathered by this weight system can be valuable and beneficial for hydroponic plants monitoring research and agricultural research applications.
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International Nuclear Information System (INIS)
Kostov, M.
2000-01-01
This report covers the following: preparatory steps for performing plant walk-down; the objective of the first plant walk-down; plant walk-down procedures; earthquake screening evaluation; walk-down documentation; second plant walk-down. The following objectives concerning the plant walk-down(s) were achieved. The plant system configuration is verified in order to proceed with event tree and fault tree analyses. Systems interactions, other types of dependencies or plant unique features are identified. he safety related components that are judged to generically possess high capacities (i.e., larger than the earthquake review level) have been verified to contain no weaknesses. Further analyses needed to establish the capacities of remaining safety-related components are identified and necessary field data are obtained. Information on components is obtained to assist in HCLPF (fragility) evaluation and peer review of the seismic margin study
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Sayre, N. F.; Bestelmeyer, B.
2015-12-01
Global livestock production is heterogeneous, and its benefits and costs vary widely across global contexts. Extensive grazing lands (or rangelands) constitute the vast majority of the land dedicated to livestock production globally, but they are relatively minor contributors to livestock-related environmental impacts. Indeed, the greatest potential for environmental damage in these lands lies in their potential for conversion to other uses, including agriculture, mining, energy production and urban development. Managing such conversion requires improving the sustainability of livestock production in the face of fragmentation, ecological and economic marginality and climate change. We present research from Mongolia and the United States demonstrating methods of improving outcomes on rangelands by improving the fit between the scales of social and biophysical processes. Especially in arid and semi-arid settings, rangelands exhibit highly variable productivity over space and time and non-linear or threshold dynamics in vegetation; climate change is projected to exacerbate these challenges and, in some cases, diminish overall productivity. Policy and governance frameworks that enable landscape-scale management and administration enable range livestock producers to adapt to these conditions. Similarly, livestock breeds that have evolved to withstand climate and vegetation change improve producers' prospects in the face of increasing variability and declining productivity. A focus on the relationships among primary production, animal production, spatial connectivity, and scale must underpin adaptation strategies in rangelands.
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Advanced plant design recommendations from Cook Nuclear Plant experience
International Nuclear Information System (INIS)
Zimmerman, W.L.
1993-01-01
A project in the American Electric Power Service Corporation to review operating and maintenance experience at Cook Nuclear Plant to identify recommendations for advanced nuclear plant design is described. Recommendations so gathered in the areas of plant fluid systems, instrument and control, testing and surveillance provisions, plant layout of equipment, provisions to enhance effective maintenance, ventilation systems, radiological protection, and construction, are presented accordingly. An example for a design review checklist for effective plant operations and maintenance is suggested
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Directory of Open Access Journals (Sweden)
Souad Neffar
2013-12-01
Full Text Available In arid and semi-arid lands, the spiny prickly pear (Opuntia ficus-indica is an outstanding plant for soil conservation and restoration. To determine the role of Opuntia ficus-indica on vegetation recovery process in desertified areas of Southern Tebessa (Northeast Algeria, we investigated the effect of prickly pear plantation age and some soil properties (grain size, pH, electrical conductivity, organic matter, total nitrogen, available phosphorus, and CaCO3 equivalents on native plant community. Vegetation cover and plant diversity were assessed by calculating the number of individual plants (N, species richness (S, their ratio (N/S, Shannon index, and Evenness in prickly pear plantation plots of different ages (control, 5 and 20 years. Even if surveyed soil parameters did not differ significantly among O. ficus-indica plantations, results of ANOVA testing the effect of Opuntia plantations on native vegetation traits revealed significant variation for plant abundance (P < 0.0001, N/S ratio (P = 0.003 and vegetation cover (P < 0.0001. Vegetation cover differed significantly with both prickly-pear plantation age (P = 0.031 and seasons (P = 0.019. Tukey's tests revealed that all vegetation traits were significantly higher on prickly pear plantations than in control plots. Multiple comparisons also showed that plant abundance, N/S ratio and vegetation cover were significantly different between both young and old plantations and the controls. Prickly pear cultures facilitated the colonization and development of herbaceous species by ameliorating the severe environmental conditions. In conclusion, the facilitative effect of O. ficus-indica has been clearly demonstrated for both abundance and cover of native vegetation.
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2004-04-22
herbivores on Ipomopsis arizonica . In addition, litter and neighboring plants can influence herbivore damage by concealing seeds and small seedlings...1991. Facilitation and interference of Quercus douglasii on understory productivity in central California. - Ecology 72: 1484- 1499. 66 Callaway, R
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Desertification, the broad-scale conversion of perennial grasslands to dominance by xerophytic shrubs, and the attendant consequences to ecosystem services has affected arid and semiarid regions globally over the past several centuries. This state change is expected to continue in the future as envi...
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PlantDB – a versatile database for managing plant research
Directory of Open Access Journals (Sweden)
Gruissem Wilhelm
2008-01-01
Full Text Available Abstract Background Research in plant science laboratories often involves usage of many different species, cultivars, ecotypes, mutants, alleles or transgenic lines. This creates a great challenge to keep track of the identity of experimental plants and stored samples or seeds. Results Here, we describe PlantDB – a Microsoft® Office Access database – with a user-friendly front-end for managing information relevant for experimental plants. PlantDB can hold information about plants of different species, cultivars or genetic composition. Introduction of a concise identifier system allows easy generation of pedigree trees. In addition, all information about any experimental plant – from growth conditions and dates over extracted samples such as RNA to files containing images of the plants – can be linked unequivocally. Conclusion We have been using PlantDB for several years in our laboratory and found that it greatly facilitates access to relevant information.
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Top 10 plant viruses in molecular plant pathology.
Scholthof, Karen-Beth G; Adkins, Scott; Czosnek, Henryk; Palukaitis, Peter; Jacquot, Emmanuel; Hohn, Thomas; Hohn, Barbara; Saunders, Keith; Candresse, Thierry; Ahlquist, Paul; Hemenway, Cynthia; Foster, Gary D
2011-12-01
Many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. However, to our knowledge, no such list exists. The aim of this review was to survey all plant virologists with an association with Molecular Plant Pathology and ask them to nominate which plant viruses they would place in a 'Top 10' based on scientific/economic importance. The survey generated more than 250 votes from the international community, and allowed the generation of a Top 10 plant virus list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Tobacco mosaic virus, (2) Tomato spotted wilt virus, (3) Tomato yellow leaf curl virus, (4) Cucumber mosaic virus, (5) Potato virus Y, (6) Cauliflower mosaic virus, (7) African cassava mosaic virus, (8) Plum pox virus, (9) Brome mosaic virus and (10) Potato virus X, with honourable mentions for viruses just missing out on the Top 10, including Citrus tristeza virus, Barley yellow dwarf virus, Potato leafroll virus and Tomato bushy stunt virus. This review article presents a short review on each virus of the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant virology community, as well as laying down a benchmark, as it will be interesting to see in future years how perceptions change and which viruses enter and leave the Top 10. © 2011 The Authors. Molecular Plant Pathology © 2011 BSPP and Blackwell Publishing Ltd.
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International Nuclear Information System (INIS)
1985-01-01
Data concerning the existing nuclear power plants in the world are presented. The data was retrieved from the SIEN (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: nuclear plants, its status and type; installed nuclear power plants by country; nuclear power plants under construction by country; planned nuclear power plants by country; cancelled nuclear power plants by country; shut-down nuclear power plants by country. (E.G.) [pt
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Evolutionary responses of native plant species to invasive plants : a review
Oduor, Ayub M. O.
2013-01-01
Strong competition from invasive plant species often leads to declines in abundances and may,in certain cases, cause localized extinctions of native plant species. Nevertheless, studies have shown that certain populations of native plant species can co-exist with invasive plant species, suggesting the possibility of adaptive evolutionary responses of those populations to the invasive plants. Empirical inference of evolutionary responses of the native plant species to invasive plants has invol...
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Soil Aggregate Stability and Grassland Productivity Associations in a Northern Mixed-Grass Prairie.
Directory of Open Access Journals (Sweden)
Kurt O Reinhart
Full Text Available Soil aggregate stability data are often predicted to be positively associated with measures of plant productivity, rangeland health, and ecosystem functioning. Here we revisit the hypothesis that soil aggregate stability is positively associated with plant productivity. We measured local (plot-to-plot variation in grassland community composition, plant (aboveground biomass, root biomass, % water-stable soil aggregates, and topography. After accounting for spatial autocorrelation, we observed a negative association between % water-stable soil aggregates (0.25-1 and 1-2 mm size classes of macroaggregates and dominant graminoid biomass, and negative associations between the % water-stable aggregates and the root biomass of a dominant sedge (Carex filifolia. However, variation in total root biomass (0-10 or 0-30 cm depths was either negatively or not appreciably associated with soil aggregate stabilities. Overall, regression slope coefficients were consistently negative thereby indicating the general absence of a positive association between measures of plant productivity and soil aggregate stability for the study area. The predicted positive association between factors was likely confounded by variation in plant species composition. Specifically, sampling spanned a local gradient in plant community composition which was likely driven by niche partitioning along a subtle gradient in elevation. Our results suggest an apparent trade-off between some measures of plant biomass production and soil aggregate stability, both known to affect the land's capacity to resist erosion. These findings further highlight the uncertainty of plant biomass-soil stability associations.
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[Review on application of plant growth retardants in medicinal plants cultivation].
Zhai, Yu-Yao; Guo, Bao-Lin; Cheng, Ming
2013-09-01
Plant growth retardants are widely used in cultivation of medicinal plant, but there is still lack of scientific guidance. In order to guide the use of plant growth retardants in medicinal plant cultivation efficiently and reasonably, this paper reviewed the mechanism, function characteristic, plant and soil residue of plant growth retardants, such as chlorocholine chloride, mepiquat chloride, paclobutrazol, unicnazle and succinic acid, and summarized the application of plant growth retardants in medicinal plants cultivation in recent years, with focus on the effect of growth and yield of the officinal organs and secondary metabolites.
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Evolutionary responses of native plant species to invasive plants: a review.
Oduor, Ayub M O
2013-12-01
Strong competition from invasive plant species often leads to declines in abundances and may, in certain cases, cause localized extinctions of native plant species. Nevertheless, studies have shown that certain populations of native plant species can co-exist with invasive plant species,suggesting the possibility of adaptive evolutionary responses of those populations to the invasive plants. Empirical inference of evolutionary responses of the native plant species to invasive plants has involved experiments comparing two conspecific groups of native plants for differences in expression of growth/reproductive traits: populations that have experienced competition from the invasive plant species (i.e. experienced natives) versus populations with no known history of interactions with the invasive plant species (i.e. naıve natives). Here, I employ a meta-analysis to obtain a general pattern of inferred evolutionary responses of native plant species from 53 such studies. In general, the experienced natives had significantly higher growth/reproductive performances than naıve natives, when grown with or without competition from invasive plants.While the current results indicate that certain populations of native plant species could potentially adapt evolutionarily to invasive plant species, the ecological and evolutionary mechanisms that probably underlie such evolutionary responses remain unexplored and should be the focus of future studies.
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Meyer, Michael L; Huey, Greg M
2006-05-01
This study utilized telemetric systems to sample microbes and pathogens in forest, burned forest, rangeland, and urban watersheds to assess surface water quality in northern New Mexico. Four sites included remote mountainous watersheds, prairie rangelands, and a small urban area. The telemetric system was linked to dataloggers with automated event monitoring equipment to monitor discharge, turbidity, electrical conductivity, water temperature, and rainfall during base flow and storm events. Site data stored in dataloggers was uploaded to one of three types of telemetry: 1) radio in rangeland and urban settings; 2) a conventional phone/modem system with a modem positioned at the urban/forest interface; and 3) a satellite system used in a remote mountainous burned forest watershed. The major variables affecting selection of each system were site access, distance, technology, and cost. The systems were compared based on operation and cost. Utilization of telecommunications systems in this varied geographic area facilitated the gathering of hydrologic and water quality data on a timely basis.
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International Nuclear Information System (INIS)
Cao Moju; Huang Wenchao; Pan Guangtang; Rong Tingzhao; Zhu Yingguo
2004-01-01
F 2 fertility segregation population and the sister-cross fertility segregation population, which descended from the male sterile material, were analysed by their plant height of different growing stage between 2 populations of male sterile plants and male fertile plants. The plant height of different fertility plants come to the significance at 0.01 level in different stage through the whole growing period. The differences become more and more large with the development of plants, the maximum difference happens in adult stage. The increasing amount of different stage also shows significance at 0.01 level between two kinds of different fertility plants
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Configuration management of plant modifications for nuclear power plants
International Nuclear Information System (INIS)
Ritsch, W.J.
1987-01-01
Due to the increasing complexity of nuclear power plant operation, regulatory pressure, and the large numbers of people required to operate and support the stations, the control of plant modifications at these plants needs to be expanded and improved. The aerospace and defense industries, as well as the owners or operators of large energy projects have established configuration management programs (CMPs) to control plant design changes. These programs are composed of well-defined functions for identifying, evaluating, recording, tracking, issuing, and documenting the established baseline conditions, as well as required changes to these baseline conditions. The purpose of this paper is to describe a recommended CMP for plant modifications consisting of a computerized data base installed on the utility's computer to provide a central storage of plant design and operations data necessary to control the following activities as they are affected by plant design changes: training; record management; operations; maintenance; health physics; planning/scheduling; procurement/inventory control; outage management (including modifications); and emergency response
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Directory of Open Access Journals (Sweden)
Nico Eisenhauer
2011-01-01
Full Text Available One of the most significant consequences of contemporary global change is the rapid decline of biodiversity in many ecosystems. Knowledge of the consequences of biodiversity loss in terrestrial ecosystems is largely restricted to single ecosystem functions. Impacts of key plant functional groups on soil biota are considered to be more important than those of plant diversity; however, current knowledge mainly relies on short-term experiments.We studied changes in the impacts of plant diversity and presence of key functional groups on soil biota by investigating the performance of soil microorganisms and soil fauna two, four and six years after the establishment of model grasslands. The results indicate that temporal changes of plant community effects depend on the trophic affiliation of soil animals: plant diversity effects on decomposers only occurred after six years, changed little in herbivores, but occurred in predators after two years. The results suggest that plant diversity, in terms of species and functional group richness, is the most important plant community property affecting soil biota, exceeding the relevance of plant above- and belowground productivity and the presence of key plant functional groups, i.e. grasses and legumes, with the relevance of the latter decreasing in time.Plant diversity effects on biota are not only due to the presence of key plant functional groups or plant productivity highlighting the importance of diverse and high-quality plant derived resources, and supporting the validity of the singular hypothesis for soil biota. Our results demonstrate that in the long term plant diversity essentially drives the performance of soil biota questioning the paradigm that belowground communities are not affected by plant diversity and reinforcing the importance of biodiversity for ecosystem functioning.
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Directory of Open Access Journals (Sweden)
Pablo Luis Peri
2018-02-01
Full Text Available In Southern Patagonia, a long-term monitoring network has been established to assess bio-indicators as an early warning of environmental changes due to climate change and human activities. Soil organic carbon (SOC content in rangelands provides a range of important ecosystem services and supports the capacity of the land to sustain plant and animal productivity. The objectives in this study were to model SOC (30 cm stocks at a regional scale using climatic, topographic and vegetation variables, and to establish a baseline that can be used as an indicator of rangeland condition. For modelling, we used a stepwise multiple regression to identify variables that explain SOC variation at the landscape scale. With the SOC model, we obtained a SOC map for the entire Santa Cruz province, where the variables derived from the multiple linear regression models were integrated into a geographic information system (GIS. SOC stock to 30 cm ranged from 1.38 to 32.63 kg C m−2. The fitted model explained 76.4% of SOC variation using as independent variables isothermality, precipitation seasonality and vegetation cover expressed as a normalized difference vegetation index. The SOC map discriminated in three categories (low, medium, high determined patterns among environmental and land use variables. For example, SOC decreased with desertification due to erosion processes. The understanding and mapping of SOC in Patagonia contributes as a bridge across main issues such as climate change, desertification and biodiversity conservation.
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Charles, Grace K; Porensky, Lauren M; Riginos, Corinna; Veblen, Kari E; Young, Truman P
2017-01-01
Wild herbivores and livestock share the majority of rangelands worldwide, yet few controlled experiments have addressed their individual, additive, and interactive impacts on ecosystem function. While ungulate herbivores generally reduce standing biomass, their effects on aboveground net primary production (ANPP) can vary by spatial and temporal context, intensity of herbivory, and herbivore identity and species richness. Some evidence indicates that moderate levels of herbivory can stimulate aboveground productivity, but few studies have explicitly tested the relationships among herbivore identity, grazing intensity, and ANPP. We used a long-term exclosure experiment to examine the effects of three groups of wild and domestic ungulate herbivores (megaherbivores, mesoherbivore wildlife, and cattle) on herbaceous productivity in an African savanna. Using both field measurements (productivity cages) and satellite imagery, we measured the effects of different herbivore guilds, separately and in different combinations, on herbaceous productivity across both space and time. Results from both productivity cage measurements and satellite normalized difference vegetation index (NDVI) demonstrated a positive relationship between mean productivity and total ungulate herbivore pressure, driven in particular by the presence of cattle. In contrast, we found that variation in herbaceous productivity across space and time was driven by the presence of wild herbivores (primarily mesoherbivore wildlife), which significantly reduced heterogeneity in ANPP and NDVI across both space and time. Our results indicate that replacing wildlife with cattle (at moderate densities) could lead to similarly productive but more heterogeneous herbaceous plant communities in rangelands. © 2016 by the Ecological Society of America.
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Perspectives on plant vulnerabilities ampersand other plant and containment improvements
International Nuclear Information System (INIS)
LaChance, J.; Kolaczkowski, A.; Kahn, J.
1996-01-01
The primary goal of the Individual Plant Examination (IPE) Program was for licensees to identify plant-unique vulnerabilities and actions to address these vulnerabilities. A review of these vulnerabilities and plant improvements that were identified in the IPEs was performed as part of the IPE Insights Program sponsored by the U.S. Nuclear Regulatory Commission (NRC). The purpose of this effort was to characterize the identified vulnerabilities and the impact of suggested plant improvements. No specific definition for open-quotes vulnerabilityclose quotes was provided in NRC Generic Letter 88-20 or in the subsequent NRC IPE submittal guidance documented in NUREG-1335. Thus licensees were left to use their own definitions. Only 20% of the plants explicitly stated that they had vulnerabilities. However, most licensees identified other plant improvements to address issues not explicitly classified as vulnerabilities, but pertaining to areas in which overall plant safety could potentially be increased. The various definitions of open-quotes vulnerabilityclose quotes used by the licensees, explicitly identified vulnerabilities, proposed plant improvements to address these vulnerabilities, and other plant improvements are summarized and discussed
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Life management plants at nuclear power plants PWR
International Nuclear Information System (INIS)
Esteban, G.
2014-01-01
Since in 2009 the CSN published the Safety Instruction IS-22 (1) which established the regulatory framework the Spanish nuclear power plants must meet in regard to Life Management, most of Spanish nuclear plants began a process of convergence of their Life Management Plants to practice 10 CFR 54 (2), which is the current standard of Spanish nuclear industry for Ageing Management, either during the design lifetime of the plant, as well as for Long-Term Operation. This article describe how Life Management Plans are being implemented in Spanish PWR NPP. (Author)
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A spatial dynamic model to assess piospheric land degradation processes of SW Iberian rangelands
Herguido Sevillano, Estela; Ibáñez, Javier; Francisco Lavado Contador, Joaquín; Pulido-Fernández, Manuel; Schnabel, Susanne
2015-04-01
Iberian open wooded rangelands (known as dehesas or montados) constitute valuable agro-silvo-pastoral systems traditionally considered as highly sustainable. Nevertheless, in the recent decades, those systems are undergoing changes of land use and management practices that compromise its sustainability. Some of those changes, as the rising construction of watering points and the high spatial fragmentation and livestock movement restriction associated to fencing, show an aggregated effect with livestock, producing an impact gradient over soil and vegetation. Soil compaction related to livestock pressure is higher around watering points, with bare soil halos and patches of scarce vegetation or nude soil developing with higher frequency in areas close to them. Using the freeware Dinamica EGO as environmental modeling platform, we have developed a theoretic spatial dynamic model that represents some of the processes of land degradation associated to livestock grazing in dehesa fenced enclosures. Spatial resolution is high since every cell in the model is a square unit area of 1 m2. We paid particular attention to the relationships between soil degradation by compaction (porosity), livestock pressure, rainfall, pasture growth and shrub cover and bare soil generation. The model considers pasture growth as related to soil compaction, measured by the pore space in the top 10 cm soil layer. Annual precipitation is randomly generated following a normal distribution. When annual precipitation and pore space increase, also does pasture growth. Besides, there is a feedback between pasture growth and pore space, given that pasture roots increases soil porosity. The cell utility for livestock function has been defined as an exponential function of the distance of a cell to watering points and the amount of pasture present in it. The closer the cell to a pond and the higher the amount of pasture, the higher is cell utility. The latter is modulated by a normal random variable to
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Historical plant cost and annual production expenses for selected electric plants, 1982
International Nuclear Information System (INIS)
1984-01-01
This publication is a composite of the two prior publications, Hydroelectric Plant Construction Cost and Annual Production Expenses and Thermal-Electric Plant Construction Cost and Annual Production Expenses. Beginning in 1979, Thermal-Electric Plant Construction Cost and Annual Production Expenses contained information on both steam-electric and gas-turbine electric plant construction cost and annual production expenses. The summarized historical plant cost described under Historical Plant Cost in this report is the net cumulative-to-date actual outlays or expenditures for land, structures, and equipment to the utility. Historical plant cost is the initial investment in plant (cumulative to the date of initial commercial operation) plus the costs of all additions to the plant, less the value of retirements. Thus, historical plant cost includes expenditures made over several years, as modifications are made to the plant. Power Production Expenses is the reporting year's plant operation and maintenance expenses, including fuel expenses. These expenses do not include annual fixed charges on plant cost (capital costs) such as interest on debt, depreciation or amortization expenses, and taxes. Consequently, total production expenses and the derived unit costs are not the total cost of producing electric power at the various plants. This publication contains data on installed generating capacity, net generation, net capability, historical plant cost, production expenses, fuel consumption, physical and operating plant characteristics, and other relevant statistical information for selected plants
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1989-10-01
1978. " Ecotoxicology of aquatic plant communi- ties," Principles of Ecotoxicology , SCOPE Report 12, Chapter 11, pp 239-255. [Heavy metals, Pollutants...Phragmites communis and Equisetum limosum were cultivated . They found plant-plant influences depend on soil type. Typha latifolia, S. A2 lacustris, and
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Making Plant-Support Structures From Waste Plant Fiber
Morrow, Robert C.; < oscjmocl. < attjew K/; {ertzbprm. A,amda; Ej (e. Cjad); Hunt, John
2006-01-01
Environmentally benign, biodegradable structures for supporting growing plants can be made in a process based on recycling of such waste plant fiber materials as wheat straw or of such derivative materials as paper and cardboard. Examples of structures that can be made in this way include plant plugs, pots, planter-lining mats, plant fences, and root and shoot barriers. No chemical binders are used in the process. First, the plant material is chopped into smaller particles. The particles are leached with water or steam to remove material that can inhibit plant growth, yielding a fibrous slurry. If the desired structures are plugs or sheets, then the slurry is formed into the desired shapes in a pulp molding subprocess. If the desired structures are root and shoot barriers, pots, or fences, then the slurry is compression-molded to the desired shapes in a heated press. The processed materials in these structures have properties similar to those of commercial pressboard, but unlike pressboard, these materials contain no additives. These structures have been found to withstand one growth cycle, even when wet
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Chapter 15. Plant pathology and managing wildland plant disease systems
David L. Nelson
2004-01-01
Obtaining specific, reliable knowledge on plant diseases is essential in wildland shrub resource management. However, plant disease is one of the most neglected areas of wildland resources experimental research. This section is a discussion of plant pathology and how to use it in managing plant disease systems.
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Biogeographical diversity of plant associated microbes in arcto-alpine plants
Kumar, Manoj Gopala Krishnan
2016-01-01
Terrestrial plants and microbes have co-evolved since the emergence of the former on Earth. Associations with microorganisms can be either beneficial or detrimental for plants. Microbes can be found in the soil surrounding the plant roots, but also in all plant tissues, including seeds. In
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Exotic plant species attack revegetation plants in post-coal mining areas
Yusuf, Muhammad; Arisoesilaningsih, Endang
2017-11-01
This study aimed to explore some invasive exotic plant species that have the potential to disrupt the growth of revegetation plants in post-coal mining areas. This research was conducted in a revegetation area of PT, Amanah Anugerah Adi Mulia (A3M) Kintap site, South Borneo. Direct observation was carried out on some revegetation areas by observing the growth of revegetation plants disturbed by exotic plant species and the spread of exotic plant species. Based on observation, several invasive exotic plant species were identified including Mikania cordata, Centrosema pubescence, Calopogonium mucunoides, Mimosa pudica, Ageratum conyzoides, and Chromolaena odorata. These five plant species grew wild in the revegetation area and showed ability to disrupt the growth of other plants. In some tree species, such as Acacia mangium, Paraserianthes falcataria, M. cordata could inhibit the growth and even kill the trees through covering the tree canopy. So, the trees could not receive optimum sun light for photosynthesis processes. M. cordata was also observed to have the most widespread distribution. Several exotic plant species such as C. mucunoides, M. pudica, and A. conyzoides were observed to have deep root systems compared with plant species used for revegetation. This growth characteristic allowed exotic plant species to win the competition for nutrient absorption with other plant species.
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Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus
2015-01-01
The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448
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Rubio, Vicente; Iniesto Sánchez, Elisa; Irigoyen Miguel, María Luisa
2014-01-01
[EN] The invention relates to transgenic plants and methods for modulating abscisic acid (ABA) perception and signal transduction in plants. The plants find use in increasing yield in plants, particularly under abiotic stress.
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The application of plant information system on third Qinshan nuclear power plant
International Nuclear Information System (INIS)
Liu Wangtian
2005-01-01
Plant overall control has been applied in Qinshan Nuclear Power Plant, which enhances the security of plant operation, but it is not enough to improve the technical administration level. In order to integrate the overall information and to improve the technical administration level more. Third Qinshan Nuclear Power Plant applies the plant information system. This thesis introduces the application of plant information system in Third Qinshan Nuclear Power Plant and the effect to the plant after the system is carried into execution, in addition, it does more analysis and exceptions for application of plant information system in the future. (authors)
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Linking plant nutritional status to plant-microbe interactions.
Carvalhais, Lilia C; Dennis, Paul G; Fan, Ben; Fedoseyenko, Dmitri; Kierul, Kinga; Becker, Anke; von Wiren, Nicolaus; Borriss, Rainer
2013-01-01
Plants have developed a wide-range of adaptations to overcome nutrient limitation, including changes to the quantity and composition of carbon-containing compounds released by roots. Root-associated bacteria are largely influenced by these compounds which can be perceived as signals or substrates. Here, we evaluate the effect of root exudates collected from maize plants grown under nitrogen (N), phosphate (P), iron (Fe) and potassium (K) deficiencies on the transcriptome of the plant growth promoting rhizobacterium (PGPR) Bacillus amyloliquefaciens FZB42. The largest shifts in gene expression patterns were observed in cells exposed to exudates from N-, followed by P-deficient plants. Exudates from N-deprived maize triggered a general stress response in FZB42 in the exponential growth phase, which was evidenced by the suppression of numerous genes involved in protein synthesis. Exudates from P-deficient plants induced bacterial genes involved in chemotaxis and motility whilst exudates released by Fe and K deficient plants did not cause dramatic changes in the bacterial transcriptome during exponential growth phase. Global transcriptional changes in bacteria elicited by nutrient deficient maize exudates were significantly correlated with concentrations of the amino acids aspartate, valine and glutamate in root exudates suggesting that transcriptional profiling of FZB42 associated with metabolomics of N, P, Fe and K-deficient maize root exudates is a powerful approach to better understand plant-microbe interactions under conditions of nutritional stress.
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Plant diversity and plant identity influence Fusarium communities in soil.
LeBlanc, Nicholas; Kinkel, Linda; Kistler, H Corby
2017-01-01
Fusarium communities play important functional roles in soil and in plants as pathogens, endophytes, and saprotrophs. This study tests how rhizosphere Fusarium communities may vary with plant species, changes in the diversity of the surrounding plant community, and soil physiochemical characteristics. Fusarium communities in soil associated with the roots of two perennial prairie plant species maintained as monocultures or growing within polyculture plant communities were characterized using targeted metagenomics. Amplicon libraries targeting the RPB2 locus were generated from rhizosphere soil DNAs and sequenced using pyrosequencing. Sequences were clustered into operational taxonomic units (OTUs) and assigned a taxonomy using the Evolutionary Placement Algorithm. Fusarium community composition was differentiated between monoculture and polyculture plant communities, and by plant species in monoculture, but not in polyculture. Taxonomic classification of the Fusarium OTUs showed a predominance of F. tricinctum and F. oxysporum as well of the presence of a clade previously only found in the Southern Hemisphere. Total Fusarium richness was not affected by changes in plant community richness or correlated with soil physiochemical characteristics. However, OTU richness within two predominant phylogenetic lineages within the genus was positively or negatively correlated with soil physiochemical characteristics among samples within each lineage. This work shows that plant species, plant community richness, and soil physiochemical characteristics may all influence the composition and richness of Fusarium communities in soil.
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Plant Density Effect in Different Planting Dates on Growth Indices, Yield and
Directory of Open Access Journals (Sweden)
F Azizi
2013-04-01
Full Text Available In order to determine the appropriate plant density in different planting dates for sweet corn cultivar KSC403su, an experiment was conducted using a randomized complete block design in split plot lay out with three replications at Seed and Plant Improvement Institute in Karaj in 2006. Three planting dates (22 May, 5 June and 22 June were assigned as main plots and three plant densities (65000, 75000 and 85000 plants per hectare were considered as sub plots. Effect of planting date on row/ear, 1000 kernels weight, biological yield and harvest index was significant at 1% probability level and it was significant at 5% probability level for kernels/ear row and grain yield. All traits decreased with postponement of planting date to 5 June except for row/ear, kernels/row and grain yield. More delay in planting from 22 May to 22 June caused that grain yield was decreased significantly about 32.5% (from 14.45 to 9.78 ton/ha. Effect of plant density was significant at 1% probability level for all the traits. All of the traits decreased significantly with increasing plant density except for biological yield. The highest grain yield was resulted from 65000 plants per hectare density (14.20 ton/ha. Interaction effect of planting date and plant density was significant at 5% probability level for biological yield and harvest index but it wasn’t significant for the other traits. Growth indices decreased with delay in planting date and increasing plant density. Only leaf area index increased in more plant densities. From the results of this experiment it might be resulted that appropriate planting date to produce the highest grain yield is 22 May to 5 June for sweet corn cultivar KSC403su and also the highest grain yield can obtain from 65000 plants per hectare density.
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Murillo, M; Herrera, E; Ruiz, O; Reyes, O; Carrete, F O; Gutierrez, H
2016-05-01
increasing levels of CDDGS supplementation (p<0.05). However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05). Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05). On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns.
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Directory of Open Access Journals (Sweden)
M. Murillo
2016-05-01
increasing levels of CDDGS supplementation (p<0.05. However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05. Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05. On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns.
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Murillo, M.; Herrera, E.; Ruiz, O.; Reyes, O.; Carrete, F. O.; Gutierrez, H.
2016-01-01
increasing levels of CDDGS supplementation (p<0.05). However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05). Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05). On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns. PMID:26954168
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Phillipson, J. David
1997-01-01
Highlights the demand for medicinal plants as pharmaceuticals and the demand for health care treatments worldwide and the issues that arise from this. Discusses new drugs from plants, anticancer drugs, antiviral drugs, antimalarial drugs, herbal remedies, quality, safety, efficacy, and conservation of plants. Contains 30 references. (JRH)
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Regulatory requirements for desalination plant coupled with nuclear reactor plant
International Nuclear Information System (INIS)
Yune, Young Gill; Kim, Woong Sik; Jo, Jong Chull; Kim, Hho Jung; Song, Jae Myung
2005-01-01
A small-to-medium sized reactor has been developed for multi-purposes such as seawater desalination, ship propulsion, and district heating since early 1990s in Korea. Now, the construction of its scaled-down research reactor, equipped with a seawater desalination plant, is planned to demonstrate the safety and performance of the design of the multi-purpose reactor. And the licensing application of the research reactor is expected in the near future. Therefore, a development of regulatory requirements/guides for a desalination plant coupled with a nuclear reactor plant is necessary for the preparation of the forthcoming licensing review of the research reactor. In this paper, the following contents are presented: the design of the desalination plant, domestic and foreign regulatory requirements relevant to desalination plants, and a draft of regulatory requirements/guides for a desalination plant coupled with a nuclear reactor plant
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International Nuclear Information System (INIS)
Fukumitsu, Hiroyuki
1998-01-01
A simulator of a reactor plant of the present invention comprises a plurality of distributed computers, an indication processing section and an operation section. The simulation calculation functions of various kinds of plant models in the plant are shared by the plurality of computers. The indication processing section controls collection of data of the plant simulated by the computers and instructions of an operator. The operation section is operated by the operator and the results of operation are transmitted to the indication processing section, to conduct operation trainings and display the results of the simulation. Each of the computers and the indication processing portion are connected with each other by a network having a memory for common use. Data such as the results of calculation of plant models and various kinds of parameters of the plant required commonly to the calculators and the indication processing section are stored in the common memory, and adapted to be used by way of the network. (N.H.)
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Directory of Open Access Journals (Sweden)
Ayana Abdeta
2011-10-01
Full Text Available We investigated the impact of Acacia drepanolobium, a species threatening rangeland resources including Gum-resin production and pastoralists’ livelihoods in Borana. Data were collected through vegetation surveys, key informant interviews, use of formal questionnaires and focus group discussions. We found a total of 22 woody species in the study area. A. drepanolobium was found to be the most dominant (22% and abundant (65% invasive woody species with an importance value index (IVI of 103. According to our respondents, A. drepanolobium was the first widely expanded woody species followed by Dichrostachys cinerea and A. mellifera. Eighty seven percent of our respondents ranked A. drepanolobium as the most invading woody species during their life time. Overall, our results demonstrated that the impact of A. drepanolobium had greatly affected the condition of rangeland vegetation. The implication is that the reduction in the capacity of rangelands for livestock grazing could reduce the resilience of local livelihood under changing environmental conditions. Furthermore, pastoralists’ perception indicated that the expansion of A. drepanolobium had reduced the survival of Gum-resin producing species. Generally, the shift from cattle based pastoral economy to mixed livestock types could be attributed to the expansion of A. drepanolobium that forced the community to shift their mode of production. We confirmed that A. drepanolobium is an invasive indigenous woody species with multiple effects on the ecology of rangelands and on the livelihood security of pastoral communities.
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[Distribution of HCB discharged from a chemical plant in plants].
Chen, Jing; Wang, Lin-Ling; Lu, Xiao-Hua; Yuan, Song-Hu; Liu, Xi-Xiang; Wang, Yue; Zhao, Qian; Mei, Ling-Fang
2009-04-15
The distribution characteristics of hexachlorobenzene (HCB) in plant and rhizosphere soil in contamination conduit, a nearby river and a cropland were studied and the impact factors were also discussed. The results are summarized as follows: the range of the HCB concentration in plant and rhizosphere soil in investigation area were respectively from 4.45 microg x kg(-1) to 1,189.89 microg x kg(-1) (dw) and from 27.93 microg x kg(-1) to 3,480.71 microg x kg(-1) (dw). Higher enrichment of HCB in woodplant than herbs due to higher fat concentration in woodplant in the contamination conduit and the rich concentrtion factor of woodplant and herbs were 0.41-2.55 and 0.01-1.34. The range of HCB concentrations in plants in nearby croplands was significantly wide (4.45-333.1 microg x kg(-1)) while HCB concentrations in different parts of plant were various, e.g. HCB concentrations in fruit, root and shoot of taro were 318.77 microg x kg(-1), 281.02 microg x kg(-1) and 10.94 microg x kg(-1). There was a remarkable positive relation between the concentrations of HCB in plant and fat concentration of plant while no relativity between the concentrations of HCB in plant and those in ground soils in the contamination conduit and cropland. The concentration levels of HCB in plant and rhizosphere soil in river were dramatically decreased with increasing distance from contaminated conduit. There was a remarkable positive relation between the concentrations of HCB in plant and those in ground soils but no relation between concentrations of HCB in plant and fat concentration of plant in river. The distribution characteristics of HCB in plants were influenced by contaminated levels, fat concentration and Partition-transfer model.
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DEFF Research Database (Denmark)
2006-01-01
A method for producing a plant extract comprises incubating a plant material with an enzyme composition comprising a lipolytic enzyme.......A method for producing a plant extract comprises incubating a plant material with an enzyme composition comprising a lipolytic enzyme....
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Integrating Studies on Plant-Pollinator and Plant-Herbivore Interactions
Lucas-Barbosa, Dani
2016-01-01
Research on herbivore-induced plant defence and research on pollination ecology have had a long history of separation. Plant reproduction of most angiosperm species is mediated by pollinators, and the effects of herbivore-induced plant defences on pollinator behaviour have been largely neglected.
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Steele, Gregory V.; Gurdak, Jason J.; Hobza, Christopher M.
2014-01-01
Uncertainty about the effects of land use and climate on water movement in the unsaturated zone and on groundwater recharge rates can lead to uncertainty in water budgets used for groundwater-flow models. To better understand these effects, a cooperative study between the U.S. Geological Survey and the Central Platte Natural Resources District was initiated in 2007 to determine field-based estimates of recharge rates in selected land-use areas of the Central Platte Natural Resources District in Nebraska. Measured total water potential and unsaturated-zone profiles of tritium, chloride, nitrate as nitrogen, and bromide, along with groundwater-age dates, were used to evaluate water movement in the unsaturated zone and groundwater recharge rates in the central Platte River study area. Eight study sites represented an east-west precipitation contrast across the study area—four beneath groundwater-irrigated cropland (sites 2, 5, and 6 were irrigated corn and site 7 was irrigated alfalfa/corn rotation), three beneath rangeland (sites 1, 4, and 8), and one beneath nonirrigated cropland, or dryland (site 3). Measurements of transient vertical gradients in total water potential indicated that periodic wetting fronts reached greater mean maximum depths beneath the irrigated sites than beneath the rangeland sites, in part, because of the presence of greater and constant antecedent moisture. Beneath the rangeland sites, greater temporal variation in antecedent moisture and total water potential existed and was, in part, likely a result of local precipitation and evapotranspiration. Moreover, greater variability was noticed in the total water potential profiles beneath the western sites than the corresponding eastern sites, which was attributed to less mean annual precipitation in the west. The depth of the peak post-bomb tritium concentration or the interface between the pre-bomb/post-bomb tritium, along with a tritium mass balance, within sampled soil profiles were used to
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Baas, R.; Slootweg, G.
2004-01-01
For on-line plant monitoring equipment to be functional in commercial glasshouse horticulture, relations between sensor readings and plant responses on both the short (days) and long term (weeks) are required. For this reason, systems were installed to monitor rockwool grown gerbera plants on a
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International Nuclear Information System (INIS)
Yadav, J.S.; Agarwal, K.
2017-01-01
The journey of Indian nuclear fuel reprocessing started with the commissioning of Plutonium Plant (PP) at Trombay on 22"n"d January, 1965 with an aim to reprocess the spent fuel from research reactor CIRUS. The basic process chosen for the plant was Plutonium Uranium Reduction EXtraction (PUREX) process. In seventies, the plant was subjected to major design modifications and replacement of hardware, which later met the additional demand from research reactor DHRUVA. The augmented plutonium plant has been operating since 1983. Experience gained from this plant was very much helpful to design future reprocessing plant in the country
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Kupper, Jacqueline; Reichert, Cornelia
2009-05-01
Ingestions of plants rarely lead to life-threatening intoxications. Highly toxic plants, which can cause death, are monkshood (Aconitum sp.), yew (Taxus sp.) and autumn crocus (Colchicum autumnale). Lethal ingestions of monkshood and yew are usually suicides, intoxications with autumn crocus are mostly accidental ingestions of the leaves mistaken for wild garlic (Allium ursinum). Severe intoxications can occur with plants of the nightshade family like deadly nightshade (Atropa belladonna), angel's trumpet (Datura suaveolens) or jimsonweed (Datura stramonium). These plants are ingested for their psychoactive effects. Ingestion of plant material by children most often only causes minor symptoms or no symptoms at all, as children usually do not eat great quantities of the plants. They are especially attracted by the colorful berries. There are plants with mostly cardiovascular effects like monkshood, yew and Digitalis sp. Some of the most dangerous plants belong to this group. Plants of the nightshade family cause an anticholinergic syndrome. With golden chain (Laburnum anagyroides), castor bean (Ricinus communis) and raw beans (Phaseolus vulgaris) we see severe gastrointestinal effects. Autumn crocus contains a cell toxin, colchicine, which leads to multiorgan failure. Different plants are irritative or even caustic to the skin. Treatment is usually symptomatic. Activated charcoal is administered within one hour after ingestion (1 g/kg). Endoscopic removal of plant material can be considered with ingestions of great quantities of highly toxic plants. Administration of repeated doses of charcoal (1-2 g/h every 2-4 hours) may be effective in case of oleander poisoning. There exist only two antidotes: Anti-digoxin Fab fragments can be used with cardenolide glycoside-containing plants (Digitalis sp., Oleander). Physostigmine is the antidote for severe anticholinergic symptoms of the CNS. Antibodies against colchicine, having been developed in France, are not available at
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Community Structure and Productivity in Western Mongolian Steppe
Directory of Open Access Journals (Sweden)
Kiyokazu Kawada
2014-12-01
Full Text Available The people of the Mongolian steppe have maintained a sustainable, nomadic lifestyle. However, several ecological processes are threatening their way of life. Ecological changan be detected through the analysis of quantitative and qualitative data. It is therefore, imperative to develop a sustainable rangeland management system aimed at combating desertifi cation. In this study we quantitatively and qualitatively describe several western Mongolian steppe plant communities by examining species composition, plant volume and community structure. Study sites were located in the Uvs and Khovd provinces and had all been affected by livestock grazing. A total of 48 species were found. Stipa krylovii , S . gobica , Cleistogenes songorica , Koeleria cristata and Ajania achilleoides were dominant. There was a signifi cant relationship between biomass and plant volume at all sites. Study sites were classifi ed into four groups using cluster analysis, based on the presence or absence of several species. More than 90% of plant volumes at all groups were perennial grasses and perennial forbs. The ratio of C 3 to C 4 plants at site 3 was reversed in comparison to the other sites. Species highly palatable to livestock were dominant at all sites. To ensure the sustainable use of biological resources in these arid areas, these fi ndings should be taken into account in designing land-use plans.
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Plant life management and maintenance technologies for nuclear power plants
International Nuclear Information System (INIS)
Ikegami, Tsukasa; Aoki, Masataka; Shimura, Takao; Kaimori, Kimihiro; Koike, Masahiro
2001-01-01
Nuclear power generation occupying an important position for energy source in Japan and supplying about one third of total electric power usage is now required for further upgrading of its economics under regulation relaxation of electric power business. And, under execution retardation of its new planning plant, it becomes important to operate the already established plants for longer term and to secure their stability. Therefore, technical development in response to the plant life elongation is promoted under cooperation of the Ministry of Economics and Industries, electric power companies, literate, and plant manufacturers. Under such conditions, the Hitachi, Ltd. has progressed some technical developments on check inspection, repairs and maintenance for succession of the already established nuclear power plants for longer term under securing of their safety and reliability. And in future, by proposing the check inspection and maintenance program combined with these technologies, it is planned to exert promotion of maintenance program with minimum total cost from a viewpoint of its plant life. Here were described on technologies exerted in the Hitachi, Ltd. such as construction of plant maintenance program in response to plant life elongation agreeing with actual condition of each plant, yearly change mechanism grasping, life evaluation on instruments and materials necessary for maintenance, adequate check inspection, repairs and exchange, and so forth. (G.K.)