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1
Cripps, M. G., M. R. McNeill, H. Patrick, B. Wiseman, F. Nobilly, and G. R. Edwards. "Invertebrate abundance and diversity in intensively managed dairy pastures." New Zealand Plant Protection 65 (January 8, 2012): 295. http://dx.doi.org/10.30843/nzpp.2012.65.5411.
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The invertebrate community richness diversity and abundance associated with pasture productivity and plant species richness at the Lincoln University Research Dairy Farm was examined Invertebrates were sampled in November 2010 (spring) and March 2011 (late summer) by pitfall traps in two pastures types simple (perennial ryegrass/white clover) and complex (perennial ryegrass white clover prairie grass chicory plantain red clover) Pooled across seasons invertebrate richness was greater in the complex pasture compared to the simple pasture but there were no differences in invertebrate community diversity or total abundance between pasture types However greater productivity of the complex pasture in late summer resulted in greater invertebrate abundance in this pasture type but without a concomitant increase in invertebrate species richness or diversity These preliminary results suggest that pasture productivity drives invertebrate abundance and that pasture plant richness drives invertebrate richness regardless of productivity
2
Sanderson, M. A., S. C. Goslee, K. J. Soder, R. H. Skinner, B. F. Tracy, and A. Deak. "Plant species diversity, ecosystem function, and pasture Management—A perspective." Canadian Journal of Plant Science 87, no. 3 (July 1, 2007): 479–87. http://dx.doi.org/10.4141/p06-135.
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Grassland farmers face many challenges in pasture management including improving sustainability, reducing inputs of fertilizers and pesticides, and protecting soil resources. In this paper we provide our perspective on managing plant diversity within and among pastures as one tool to aid producers in meeting these challenges. Pasture ecosystems can be highly diverse, with a complex array of organisms contributing to ecosystem functioning. Within the broad range of plant and animal biodiversity in pastures, plant species diversity may be the most amenable to manipulation or management. Reported benefits of plant diversity in grasslands include: increased forage production, greater ecosystem stability in response to disturbance, and reduced invasion by exotic species such as weeds. Some view diversity as a sort of insurance policy where different species contribute in their own time or can take the place of species that fail from stress or mismanagement. Using mixtures of several forages in pastures, in some instances, can improve forage yield and reduce weed invasions. Pasture management for increased plant species diversity, however, is not simply mixing and planting as many forage species as possible. The kinds and amounts of different forage species along with their arrangement within and among pastures at the farm scale are critical features that must be considered. Tools must be developed to determine the appropriate species mixtures for varying soils, landscapes, climate and purposes to fulfill multiple functions for producers. Key words: Grazing ecosystem; forages; diversity; ecosystem function; ecosystem services
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Snow, V. O., P. N. Smale, and M. B. Dodd. "Process-based modelling to understand the impact of ryegrass diversity on production and leaching from grazed grass-clover dairy pastures." Crop and Pasture Science 64, no. 10 (2013): 1020. http://dx.doi.org/10.1071/cp13263.
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Ecological studies often suggest that natural grasslands with high species diversity will grow more biomass and leach less nitrogen (N). If this diversity effect also applies to fertilised and irrigated pastures with controlled removal of herbage, it might be exploited to design pastures that can assist the dairy industry to maintain production while reducing N leaching losses. The purpose of this study was to test whether pasture mixtures with a high functional diversity in ryegrass traits will confer on the system higher water- and N-use efficiency. The hypothesis was tested using a process-based model in which pasture mixtures were created with varying levels of diversity in ryegrass traits likely to affect pasture growth. Those traits were: the winter- or summer-dominance of growth, the ability of the plant to intercept radiation at low pasture mass, and rooting depth. Pasture production, leaching and water- and N-use efficiency were simulated for management typical of a dairy pasture. We found that the performance of the diverse ryegrass–clover mixtures was more strongly associated with the performance of the individual components than with the diversity across the components. Diverse pasture mixtures may confer other benefits, e.g. pest or disease resistance and pasture persistence. The testing here was within a selection of ryegrasses, and the greater possible diversity across species may produce different effects. However, these results suggest that highly performing pastures under fertilised and irrigated grazed conditions are best constructed by selecting components that perform well individually than by deliberately introducing diversity between components.
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Reed, Kinsey, and Ember M. Morrissey. "Bridging Ecology and Agronomy to Foster Diverse Pastures and Healthy Soils." Agronomy 12, no. 8 (August 12, 2022): 1893. http://dx.doi.org/10.3390/agronomy12081893.
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Renovating pastures to increase forage species diversity is a burgeoning practice among producers. Over a century of grassland and small-plot research suggests that increasing plant diversity can lead to improved pasture productivity, resilience, and soil health. However, it remains hard to decipher how these benefits translate to grazed production systems given the limited experimentation in realistic grazing systems. There is a disconnect between ecological and agronomic research regarding what qualifies as a “diverse” grassland or pasture. This review aims to examine the current state of research regarding plant diversity and its potential benefits for soil health in pasture systems, and outlines how we can improve our understanding and implementation of this practice in production systems.
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Maze, Jack, and Roy Turkington. "The influence of pasture age, plant density, and genotype on intraspecific diversity of Trifolium repens (white clover)." Canadian Journal of Botany 74, no. 7 (July 1, 1996): 1189–92. http://dx.doi.org/10.1139/b96-142.
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Morphological variation, as expressed in PCA axis scores, for clovers growing in different aged pastures, was apportioned to pasture age, quadrats within pastures, intraspecific densities within quadrats, and genets within densities. Of those factors that have an effect on variation, genets is the greatest, followed by quadrats, intraspecific density, and age of the pasture. There is also an age-related decline in variation in plants of Trifolium repens as seen in genetic origin, quadrats within a pasture, and intraspecific density. These results indicate a need to determine more accurately the relationship between genetic and phenotypic responses in the decline in among-plant variation over time. Keywords: Trifolium repens, variation.
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Kaur, Kamaljit, David J. Midmore, Rajesh K. Jalota, and Nanjappa Ashwath. "Pasture composition in cleared and uncleared woodlands." Australian Journal of Botany 54, no. 5 (2006): 459. http://dx.doi.org/10.1071/bt05174.
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Land clearing in Queensland is often practised to enhance pasture production, and hence, increase financial returns from beef production. The benefits of clearing have been quantified in terms of short-term gains in pasture yield but have not adequately accounted for possible medium- or longer-term impediments that may be attributed to clearing. Therefore, impacts of clearing and the subsequent sowing of exotic grasses such as Cenchrus ciliaris L. on pasture composition and production were studied. To achieve this, paired sites were selected representing cleared and uncleared pastures across three different times since clearing (i.e. 5, 11–13 and 33 years since clearing) for the three dominant tree communities of central Queensland (i.e. Eucalyptus populnea F.Muell. (poplar box), E. melanophloia F.Muell. (silver-leaved ironbark) and Acacia harpophylla F.Muell. ex. Benth. (brigalow)). The results demonstrated that species diversity declined with clearing and sowing of exotic pastures. Species diversity and pasture production were negatively related. Although pasture yield was 2–3 times greater 13 years after clearing of E. populnea and A. harpohylla, the gains in pasture yield were not consistent over time, yields being only 1.5 times greater after 33 years of clearing. In E. melanophloia, an increase in the yield of only 1.5–1.8 times occurred 5 years after clearing compared with uncleared pastures, whereas 33 years after clearing, yield was 3/4 of that in uncleared pastures. The initial gains in pasture yield were accompanied by a loss of plant diversity that may affect ecosystem functions such as nutrient cycling or soil mineralisation, and the longer-term production gains.
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Tamahina, Aida, and Urfa Turan Ogly Turabov. "Production potential of the Kabardino-Balkarian Republic pasture ecosystems." E3S Web of Conferences 262 (2021): 03023. http://dx.doi.org/10.1051/e3sconf/202126203023.
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The pasture digression of meadows followed by soil deflation is one of the pressing environmental problems. This problem is typical for mountain pastures that are constantly in economic circulation. The article presents the results of a geobotanical survey of the Zolsky pastures on the territory of the Kabardino-Balkarian Republic in 2018-2020. The results of a geobotanical survey show that the pasture phytocenoses are characterized by high floristic diversity due to the heterogeneity of edaphic and orographic factors. The flora of the pastures is represented by postwood moist sedgy-and-tussock-grass, mesophilic woodreed-and-agrostidinic grass, cereal forb, forbs cereal mesophilic and subalpine meadows, low sedgy meadow steppes. The average yield for the pasture period varies from 7.2 to 16.6 centners/ha of dry eaten mass. The consequence of prolonged pasturage and excessive pasture load was a decrease in alpha and beta diversity, the formation of low-productive secondary plant communities of non-food, poisonous and weed grasses, the destruction of sod and soil outcropping. Restoration of degraded pasture ecosystems is possible on the basis of ecological intensification, which provides for the regulation of pasture loads, adherence to grazing terms, phytomelioration using perennial grasses, and short-term isolation of pastures from grazing. This will prevent erosion processes, increase biodiversity, productivity, forage value of grass stand and stability of pasture ecosystems.
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Davis, RD, RM Boland, and AT Lisle. "The developing relationship between Stylosanthes and anthracnose after 14 years in a North Queensland pasture. 3. Diversity in the plant population." Australian Journal of Experimental Agriculture 34, no. 5 (1994): 627. http://dx.doi.org/10.1071/ea9940627.
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Host-plant diversity in a mixed accession Stylosanthes spp. pasture 14 years after establishment was demonstrated in families derived from seed and in cuttings obtained from the pasture. Glasshouse examination of the progeny from 181 field plants inoculated with 4 different pathogenicity strains of Colletotrichunz gloeosporioides indicated the widest possible spread of diversity in disease reaction. The progeny exhibited wider variation in resistance to the disease than the originally sown accessions, and when transplanted to a field site, plant phenotypic variability became increasingly evident as the progenies matured. Of 1339 transplanted progeny, 369 were not able to be conclusively categorised according to the descriptions of the originally sown accessions, indicating that outcrossing had occurred. The demonstrated plant variability is, arguably, encouraging for the management of anthracnose using genotype mixtures in the vast areas of low-input beef pastures in northern Australia.
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Zehnder, Tobias, Andreas Lüscher, Carmen Ritzmann, Caren M. Pauler, Joel Berard, Michael Kreuzer, and Manuel K. Schneider. "Dominant shrub species are a strong predictor of plant species diversity along subalpine pasture-shrub transects." Alpine Botany 130, no. 2 (September 14, 2020): 141–56. http://dx.doi.org/10.1007/s00035-020-00241-8.
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Abstract Abandonment of pastures and successional shrub expansion are widespread in European mountain regions. Moderate shrub encroachment is perceived beneficial for plant diversity by adding new species without outcompeting existing ones, yet systematic evidence is missing. We surveyed vegetation along 24 transects from open pasture into shrubland across the Swiss Alps using a new protocol distinguishing different spatial scales, shrub cover of each plot (2 × 2 m) and larger-scale zonal cover along the transect. Data were analysed using generalized linear models of shrub cover, shrub species and environmental conditions, such as geology, aspect or soil. Most shrub communities were dominated by Alnus viridis (62% of transects) and Pinus mugo (25%), and the rest by other shrub species (13%). These dominant shrub species explained vegetation response to shrub cover well, without need of environmental variables in the model. Compared to open pasture, A. viridis resulted in an immediate linear decline in plant species richness and a marginal increase in beta-diversity (maximally + 10% at 35% cover). Dense A. viridis hosted 62% less species than open pasture. In P. mugo, species richness remained stable until 40% shrub cover and dropped thereafter; beta-diversity peaked at 35% cover. Hence, scattered P. mugo increases beta-diversity without impairing species richness. In transects dominated by other shrubs, species richness and beta-diversity peaked at 40–60% shrub cover (+ 23% both). A. viridis reduced species richness in a larger area around the shrubs than P. mugo. Therefore, effects of shrub encroachment on plant diversity cannot be generalized and depend on dominant shrub species.
10
Gerard, Philippa J., Derrick J. Wilson, and Anastazia L. Docherty. "Does pasture plant diversity influence abundance and diversity of lacewings and Hymenopteran parasitoids?" New Zealand Plant Protection 71 (July 29, 2018): 207–13. http://dx.doi.org/10.30843/nzpp.2018.71.185.
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The lack of plant biodiversity in New Zealand pastoral ecosystems may limit the abundance and diversity of generalist parasitoids and predators, predisposing these ecosystems to pest outbreaks. To test this hypothesis, patches of turf were established in existing pasture during spring 2016. Four treatments of increasing plant complexity were established, commencing with ryegrass alone, and increasing exponentially up to eight species of forage plant per patch. In the summer of 2017, insects were collected from the patches and control plots using suction to assess whether or not plant diversity had influenced the abundance and diversity of lacewings and parasitic Hymenoptera aggregating in the patches. Plant species richness had no impact on lacewing abundance but fewer parasitic Hymenoptera were recovered from the ryegrass-only plots compared with more species rich plots. Also, a wider range of parasitoid families were represented in the more diverse plant treatments compared with the less diverse treatments. Such diversity may have beneficial impacts on the stability of pasture ecosystem and the risk of pest outbreaks.
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Martínez Garza, Cristina, and Henry F. Howe. "Características foliares y tasas vitales de árboles sucesionales tardíos de un bosque tropical perennifolio." Botanical Sciences 86 (May 20, 2019): 1. http://dx.doi.org/10.17129/botsci.2315.
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Restoration of vegetation in perturbed areas (e.g., abandoned pastures) with late-successional tree species may help to bypass decades of low diversity by accelerating succession. To elucidate how leaf dynamics is related to high growth rates and survival in early successional environments, we evaluated the hypothesis that plasticity in foliar demography is positively related to establishment of seven late-successional tree species growing in sunny sites (pasture and edge) and dark sites (secondary forest) at Los Tuxtlas, Veracruz, Mexico. We monitored leaves from 517 individuals from all species at all habitats during one year. Individuals growing in secondary forest and edge showed higher leaf survival and lower leaf production than those growing in pasture. Individuals with higher growth rates and survival in pasture showed high plasticity in their leaf survival and low plasticity in their leaf production (stability) while individuals in edge and secondary forest with high survivorship were those with high stability in their leaf production. Our results indicate that <em>Nectandra ambigens, Licaria velutina</em> and <em>Pouteria rhynchocarpa</em> may be planted in pastures because they show high growth rates and survival there, besides, they have different maximal height as adults and therefore they will provide structural diversity to the restored forest. Species with low plant survivorship in pastures as <em>Calophyllum brasiliense, Pimenta dioica, Amphitecna tuxtlensis</em> and <em>Eugenia inirebensis</em> should be planted in great numbers or until a canopy of pioneers develop.
12
Acharya, Mohan, Amanda J. Ashworth, Yichao Yang, Joan M. Burke, Jung Ae Lee, and Roshani Sharma Acharya. "Soil microbial diversity in organic and non-organic pasture systems." PeerJ 9 (April 22, 2021): e11184. http://dx.doi.org/10.7717/peerj.11184.
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Understanding the effects of organic pasture management on the soil microbiome is important for sustainable forage production since soil microbiome diversity contributes to improved nutrient cycling, soil structure, plant growth, and environmental resiliency; however, the soil microbiome response to pasture management is largely unknown. This study assessed the soil microbial diversity, richness, and community structure following 10 years of pasture management (organic or non-organic) of the V4 region of the 16S rRNA using the Illumina MiSeq platform. Soil samples were collected from 0–15 cm in July and August from 2017–2018 and soil nutrient properties (nutrients, carbon, nitrogen, and pH) quantified and correlated with soil microbial diversity. Overall, greater soil bacterial species richness (P ≤ 0.05) occurred in organic relative to non-organic (conventional) systems. Management affected bacterial species richness (Chao1), with greater richness occurring in organic pasture soils and less richness occurring in non-organic systems (P ≤ 0.05). Similarly, management affected bacterial evenness (Simpson’s index), with a more diverse community occurring in organically managed soils relative to non-organic pastures (P ≤ 0.05). Linear discriminant analysis effect size analysis showed statistically significant and biologically consistent differences in bacterial taxa in organic compared with non-organic soils. Therefore, there was a shift in bacterial community structure in organic relative to non-organic soils (P ≤ 0.05). Additionally, soil nutrients (Fe, Mg, Ni, S, Al, K, Cd, and Cu), pH, C, and N were correlated with one or more dominant bacterial phyla (Gemmatimonadetes, Planctomycetes, Firmicutes, Chloroflexi, Actinobacteria, and Acidobacteria). Overall, pasture management affected soil microbial diversity, with greater diversity occurring in organic than non-organic systems, likely owing to applications of organic poultry litter in organic systems compared to non-organic management (use of inorganic-fertilizers and herbicides). Results indicate that when pastures are converted to organic production systems, soil microbial richness and diversity may increase, thereby resulting in enhanced soil microbiome diversity and overall ecosystem services.
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Schon, N. L., R. A. Gray, and A. D. Mackay. "Earthworms stimulate pasture production in sheep and beef systems: their economic value." Journal of New Zealand Grasslands 78 (January 1, 2016): 89–92. http://dx.doi.org/10.33584/jnzg.2016.78.523.
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Earthworms have long been recognised to promote plant growth but their contribution to pasture production in managed pastures may be undervalued. At three field sites pasture production was measured in an area where surface active communities were found compared to a more diverse area where the additional deep burrowing earthworm Aporrectodea longa had been introduced. Caution is needed when interpreting the results, as all data are from paired areas and not replicates. The influence of earthworms on pasture production was positively correlated with the difference in abundance of the topsoil species Aporrectodea caliginosa, with this species being more abundant in the presence of A. longa at two sites. Overall, the value of diverse earthworm communities to pasture production was estimated to be $365-$440/ha annually. In managed pasture systems there is need to recognise the value of maintaining and enhancing earthworm populations. Keywords: pasture production, earthworm functional diversity
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Silcock, R. G., T. J. Hall, P. G. Filet, A. M. Kelly, D. Osten, and T. W. G. Graham. "Floristic composition and pasture condition of Aristida/Bothriochloa pastures in central Queensland. II. Soil and pasture condition interactions." Rangeland Journal 37, no. 2 (2015): 217. http://dx.doi.org/10.1071/rj14107.
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Sustainable management of native pastures requires an understanding of what the bounds of pasture composition, cover and soil surface condition are for healthy pastoral landscapes to persist. A survey of 107 Aristida/Bothriochloa pasture sites in inland central Queensland was conducted. The sites were chosen for their current diversity of tree cover, apparent pasture condition and soil type to assist in setting more objective bounds on condition ‘states’ in such pastures. Assessors’ estimates of pasture condition were strongly correlated with herbage mass (r = 0.57) and projected ground cover (r = 0. 58), and moderately correlated with pasture crown cover (r = 0.35) and tree basal area (r = 0.32). Pasture condition was not correlated with pasture plant density or the frequency of simple guilds of pasture species. The soil type of Aristida/Bothriochloa pasture communities was generally hard-setting, low in cryptogam cover but moderately covered with litter and projected ground cover (30–50%). There was no correlation between projected ground cover of pasture and estimated ground-level cover of plant crowns. Tree basal area was correlated with broad categories of soil type, probably because greater tree clearing has occurred on the more fertile, heavy-textured clay soils. Of the main perennial grasses, some showed strong soil preferences, for example Tripogon loliiformis for hard-setting soils and Dichanthium sericeum for clays. Common species, such as Chrysopogon fallax and Heteropogon contortus, had no strong soil preference. Wiregrasses (Aristida spp.) tended to be uncommon at both ends of the estimated pasture condition scale whereas H. contortus was far more common in pastures in good condition. Sedges (Cyperaceae) were common on all soil types and for all pasture condition ratings. Plants identified as increaser species were Tragus australianus, daisies (Asteraceae) and potentially toxic herbaceous legumes such as Indigofera spp. and Crotalaria spp. Pasture condition could not be reliably predicted based on the abundance of a single species or taxon but there may be scope for using integrated data for four to five ecologically contrasting plants such as Themeda triandra with daisies, T. loliiformis and flannel weeds (Malvaceae).
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López-Olmedo, L. I., J. A. Meave, and E. A. Pérez-García. "Floristic and structural contrasts between natural savannas and anthropogenic pastures in a tropical dry landscape." Rangeland Journal 29, no. 2 (2007): 181. http://dx.doi.org/10.1071/rj07007.
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The magnitude of the biological differentiation between natural savannas and pastures (anthropogenic grasslands) coexisting in a single landscape, in terms of their floristic composition and community structure, was studied in the Nizanda region, Isthmus of Tehuantepec, Oaxaca State, southern Mexico. Vegetation samples of 15 m2 each were taken at 20 savanna and 11 pasture sites. Cover- and species richness-based diversity and dominance indices were calculated. Geomorphological and edaphic characteristics were also compared. Savannas generally occurred in hill summits with very shallow and stony, discontinuous and acidic soils; contrastingly, pastures were located in piedmonts and floodplains, with more neutral and less stony soils. Savanna sites differed from pasture sites in species richness and Shannon diversity. They did not differ in Simpson dominance index, but the identity of the dominant species was different in each community: Trachypogon spicatus (L.f.) Kuntze in savanna and Megathyrsus maximus (Jacq.) B.K.Simon et S.W.L.Jacobs in pasture. A low species-level similarity (Sørensen Index) was observed between them (8.2%), and genus-level similarity was only slightly higher (27.1%). The magnitude of the biological differentiation in both community floristics and structure between these two grass-dominated communities was larger than anticipated. Current management of savannas as pasture lands may potentially trigger a severe deterioration process involving both the landscape and its plant components.
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Nadolny, Christopher. "Towards integrating farming and conservation: the role of native pastures." Pacific Conservation Biology 4, no. 1 (1998): 70. http://dx.doi.org/10.1071/pc980070.
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Agriculture has almost certainly contributed to the decline of native vegetation and wildlife in rural Australia. A prevalent culture supports agricultural systems that rely on the use of exotic plants and animals and greater use of chemicals and machinery. In general, these systems do not fully utilize or take account of the indigenous biota. The full implications of implementing such farming systems on a landscape scale are seldom considered. I use the grazing industry on the Northern Tablelands of New South Wales to illustrate two contrasting approaches: (1) "pasture improvement" involving replacement of native with exotic species versus (2) retention and management of existing native and naturalized pasture species. Pasture improvement has been refined by extensive agronomic research, plant selection and field testing of techniques. Nevertheless, the approach is losing support among farmers because of high inputs required to maintain "improved" pastures, the fragility of these pastures during droughts, low commodity prices, longterm declines in soil structure and increases in soil acidity. Other side-effects include tree decline, reduced diversity of indigenous herbaceous plant communities and loss of wildlife. Using native pastures may offer some solutions to these problems, but the level of understanding required to manage them effectively is limited. Exotic sown pastures have no clear advantage in areas with poor soils and irregular rainfall, and the environmental impacts of new developments involving large-scale pasture improvement can be unacceptable. I conclude that native and naturalised pastures are the best option for most of the region and sown pastures should be used strategically.
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Rakosy, Demetra, Elena Motivans, Valentin Ştefan, Arkadiusz Nowak, Sebastian Świerszcz, Reinart Feldmann, Elisabeth Kühn, et al. "Intensive grazing alters the diversity, composition and structure of plant-pollinator interaction networks in Central European grasslands." PLOS ONE 17, no. 3 (March 11, 2022): e0263576. http://dx.doi.org/10.1371/journal.pone.0263576.
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Complex socio-economic, political and demographic factors have driven the increased conversion of Europe’s semi-natural grasslands to intensive pastures. This trend is particularly strong in some of the most biodiverse regions of the continent, such as Central and Eastern Europe. Intensive grazing is known to decrease species diversity and alter the composition of plant and insect communities. Comparatively little is known, however, about how intensive grazing influences plant functional traits related to pollination and the structure of plant-pollinator interactions. In traditional hay meadows and intensive pastures in Central Europe, we contrasted the taxonomic and functional group diversity and composition, the structure of plant-pollinator interactions and the roles of individual species in networks. We found mostly lower taxonomic and functional diversity of plants and insects in intensive pastures, as well as strong compositional differences among the two grassland management types. Intensive pastures were dominated by a single plant with a specialized flower structure that is only accessible to a few pollinator groups. As a result, intensive pastures have lower diversity and specificity of interactions, higher amount of resource overlap, more uniform interaction strength and lower network modularity. These findings stand in contrast to studies in which plants with more generalized flower traits dominated pastures. Our results thus highlight the importance of the functional traits of dominant species in mediating the consequences of intensive pasture management on plant-pollinator networks. These findings could further contribute to strategies aimed at mitigating the impact of intensive grazing on plant and pollinator communities.
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Thompson, J. D., R. Turkington, and F. B. Holl. "The influence of Rhizobium leguminosarum biovar. trifolii on the growth and neighbour relationships of Trifolium repens and three grasses." Canadian Journal of Botany 68, no. 2 (February 1, 1990): 296–303. http://dx.doi.org/10.1139/b90-040.
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Trifolium repens was sampled from 10 areas dominated by each of Dactylis glomerata, Holcus lanatus, and Lolium perenne in each of three different-aged pastures. Cell extracts of nodule isolates of Rhizobium leguminosarum biovar. trifolii were compared using polyacrylamide gel electrophoresis. Each pasture contained a range of Rhizobium strains as defined by the protein profiles. No single strain was common to Trifolium sampled from the same grass species neighbourhood. The diversity of Rhizobium strains encountered was negatively correlated (r = −0.67; n = 9) with pasture age; old pastures showed a decrease in strain diversity. In addition, in the oldest pasture (45-year-old), tillers of the associated grasses were also sampled. In a glasshouse, ramets from each Trifolium clone and each of the three grass species were grown in all possible combinations with each of the three Rhizobium strains, plus Trifolium monocultures and an uninoculated control. All Trifolium clones gave increased yield in mixture with Lolium compared with yields with Dactylis and Holcus. Trifolium from the Holcus patches, in most cases, had higher yield than Trifolium from other grass patches. Rhizobium inoculation did not consistently increase Trifolium yield; it actually caused a decrease in yield when in mixture with Lolium. A significant Rhizobium × Trifolium interaction indicated a variable performance of each Trifolium genotype with different Rhizobium strains. The identity of the Trifolium clone had a significant effect on the yield of Holcus and Lolium, but not Dactylis. Total mixture yields were highest when Trifolium from a Lolium patch was part of the mixture. These results are discussed in the context of the hypothesis that Trifolium–grass coexistence is significantly influenced by Rhizobium strain differences.
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Jakobsson, Simon, Heather Wood, Johan Ekroos, and Regina Lindborg. "Contrasting multi-taxa functional diversity patterns along vegetation structure gradients of woody pastures." Biodiversity and Conservation 29, no. 13 (August 18, 2020): 3551–72. http://dx.doi.org/10.1007/s10531-020-02037-y.
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Abstract Woody pastures represent keystone habitats for biodiversity in agricultural landscapes, contributing to increased resource availability, landscape heterogeneity and structural variability. High taxonomic diversity is closely linked to vegetation structure in woody pastures, but examining functional characteristics of species assemblages can shed more light on the ecological mechanisms driving divergent responses to habitat characteristics and help guide good management practices. To this end, we use a multi-taxa approach to investigate how plant, bat and bird taxonomic and functional diversity are affected by pasture tree and shrub density, structural complexity and proximate forest cover in southern Sweden. In particular, we use a trait exclusion approach to estimate the sensitivity of diversity-environment relationships to specific traits. We found little congruence between corresponding diversity metrics across taxa. Bird species richness responded stronger to environmental variables than functional diversity metrics, whereas the functional response to the environment was stronger than the taxonomic response among plants and bats. While increasing tree densities increased the taxonomic diversity of all three taxa, a simultaneous functional response was only evident for plants. Contrasting measures of vegetation structure affected different aspects of functional diversity across taxa, driven by different traits. For plants and birds, traits linked to resource use contributed particularly to the functional response, whereas body mass had stronger influence on bat functional diversity metrics. Multi-taxa functional approaches are essential to understand the effects of woody pasture structural attributes on biodiversity, and ultimately inform management guidelines to preserve the biological values in woody pastures.
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Yang, Yichao, Amanda J. Ashworth, Jennifer M. DeBruyn, Cammy Willett, Lisa M. Durso, Kim Cook, Philip A. Moore, Jr., and Phillip R. Owens. "Soil bacterial biodiversity is driven by long-term pasture management, poultry litter, and cattle manure inputs." PeerJ 7 (October 1, 2019): e7839. http://dx.doi.org/10.7717/peerj.7839.
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Soil microorganisms are important for maintaining soil health, decomposing organic matter, and recycling nutrients in pasture systems. However, the impact of long-term conservation pasture management on soil microbial communities remains unclear. Therefore, soil microbiome responses to conservation pasture management is an important component of soil health, especially in the largest agricultural land-use in the US. The aim of this study was to identify soil microbiome community differences following 13-years of pasture management (hayed (no cattle), continuously grazed, rotationally grazed with a fenced, un-grazed and unfertilized buffer strip, and a control (no poultry litter or cattle manure inputs)). Since 2004, all pastures (excluding the control) received annual poultry litter at a rate of 5.6 Mg ha−1. Soil samples were collected at a 0–15 cm depth from 2016–2017 either pre or post poultry litter applications, and bacterial communities were characterized using Illumina 16S rRNA gene amplicon sequencing. Overall, pasture management influenced soil microbial community structure, and effects were different by year (P < 0.05). Soils receiving no poultry litter or cattle manure had the lowest richness (Chao). Continuously grazed systems had greater (P < 0.05) soil community richness, which corresponded with greater soil pH and nutrients. Consequently, continuously grazed systems may increase soil diversity, owing to continuous nutrient-rich manure deposition; however, this management strategy may adversely affect aboveground plant communities and water quality. These results suggest conservation pasture management (e.g., rotationally grazed systems) may not improve microbial diversity, albeit, buffer strips were reduced nutrients and bacterial movement as evident by low diversity and fertility in these areas compared to areas with manure or poultry litter inputs. Overall, animal inputs (litter or manure) increased soil microbiome diversity and may be a mechanism for improved soil health.
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Silcock, R. G., T. J. Hall, P. G. Filet, A. M. Kelly, D. Osten, C. M. Schefe, and P. T. Knights. "Floristic composition and pasture condition of Aristida/Bothriochloa pastures in central Queensland. I. Pasture floristics." Rangeland Journal 37, no. 2 (2015): 199. http://dx.doi.org/10.1071/rj14106.
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A survey was conducted in central inland Queensland, Australia of 108 sites that were deemed to contain Aristida/Bothriochloa native pastures to quantitatively describe the pastures and attempt to delineate possible sub-types. The pastures were described in terms of their floristic composition, plant density and crown cover. There were generally ~20 (range 5–33) main pasture species at a site. A single dominant perennial grass was rare with three to six prominent species the norm. Chrysopogon fallax (golden-beard grass) was the perennial grass most consistently found in all pastures whereas Aristida calycina (dark wiregrass), Enneapogon spp. (bottlewasher grasses), Brunoniella australis (blue trumpet) and Panicum effusum (hairy panic) were all regularly present. The pastures did not readily separate into broad floristic sub-groups, but three groups that landholders could recognise from a combination of the dominant tree and soil type were identified. The three groups were Eucalyptus crebra (narrow-leaved ironbark), E. melanophloia (silver-leaved ironbark) and E. populnea (poplar box). The pastures of the three main sub-groups were then characterised by the prominent presence, singly or in combination, of Bothriochloa ewartiana (desert bluegrass), Eremochloa bimaculata (poverty grass), Bothriochloa decipiens (pitted bluegrass) or Heteropogon contortus (black speargrass). The poplar box group had the greatest diversity of prominent grasses whereas the narrow-leaved ironbark group had the least. Non-native Cenchrus ciliaris (buffel grass) and Melinis repens (red Natal grass) were generally present at low densities. Describing pastures in terms of frequency of a few species or species groups sometimes failed to capture the true nature of the pasture but plant abundance for most species, as density, herbage mass of dry matter or plant crown cover, was correlated with its recorded frequency. A quantitative description of an average pasture in fair condition is provided but it was not possible to explain why some species often occur together or fail to co-exist in Aristida/Bothriochloa pastures, for example C. ciliaris and E. bimaculata rarely co-exist whereas Tragus australianus (small burrgrass) and Enneapogon spp. are frequently recorded together. Most crown cover was provided by perennial grasses but many of these are Aristida spp. (wiregrasses) and not regarded as useful forage for livestock. No new or improved categorisation of the great variation evident in the Aristida/Bothriochloa native pasture type can be given despite the much improved detail provided of the floristic composition by this survey.
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McElroy, M. S., Y. A. Papadopoulos, and M. S. Adl. "Complexity and composition of pasture swards affect plant productivity and soil organisms." Canadian Journal of Plant Science 92, no. 4 (July 2012): 687–97. http://dx.doi.org/10.4141/cjps2011-147.
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McElroy, M. S., Papadopoulos, Y. A. and Adl, M. S. 2012. Complexity and composition of pasture swards affect plant productivity and soil organisms. Can. J. Plant Sci. 92: 687–697. The relationships between ecosystem diversity, productivity, and stability is a central theme in current ecological research; the links between above-ground and below-ground ecosystems, as well as their effects on ecosystem services, are becoming more understood. While plant communities differ in primary productivity, and in the communities of soil organisms they support, it is unclear whether these differences are attributable mainly to plant community diversity or to the dominant plant species. This study evaluated the effect of these two factors on plant productivity, and abundance of soil microorganisms and functional diversity, in an establishing pasture using sward complexity (plant species present) and sward composition (identity of species) as treatments in a design using the step-wise addition of grass species. While sward complexity affected plant productivity, showing higher productivity in plots of higher diversity, abundance and functional diversity of soil organism groups were generally not consistently affected by sward complexity or composition. Sward composition did influence soil community composition; there was a close correlation between microbial catabolic activity and sward composition. This study shows that grassland plants have a limited effect on the size and diversity of soil communities while they are being established. This result may have consequences for soil ecosystem services.
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Raynor, Edward J., Devan Allen McGranahan, James R. Miller, Diane M. Debinski, Walter H. Schacht, and David M. Engle. "Moderate Grazer Density Stabilizes Forage Availability More Than Patch Burning in Low-Stature Grassland." Land 10, no. 4 (April 9, 2021): 395. http://dx.doi.org/10.3390/land10040395.
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Spatially patchy fire creates landscape-level diversity that in turn stabilizes several rangeland ecosystem services, including forage production and habitat availability. To enhance biodiversity and livestock production, efforts are underway to restore fire regimes in rangelands throughout the Great Plains. However, invasive species such as tall fescue Schedonorus arundinaceus syn. Festuca arundinacea, initially introduced for forage production, hamper prescribed fire use. Grazer density, or stocking rate, modulates the effect of patchy fire regimes on ecological patterns in invaded, semi-natural rangeland pastures. We compare three diversity–stability responses—temporal variability in aboveground plant biomass, portfolio effects among plant functional groups, and beta diversity in plant functional group composition—in pastures managed with two different fire regimes through three periods of heavy, light, and moderate stocking rate in southern Iowa, USA. Pastures were either burned in patches, with one-third of the pasture burned each year, or completely burned every third year. The period of moderate grazer density had the least temporal variability in aboveground plant biomass, regardless of fire regime. We also found statistical evidence for a portfolio effect under moderate stocking, where diversification of plant communities through varying cover of functional groups can stabilize communities by reducing year-to-year variability. Beta diversity among plant functional groups was greatest during the moderate grazer density period as well. The short stature of tall fescue prevented the patch-burning regime to create contrast in vegetation structure among patches, and there was no difference in any diversity–stability mechanism response across the two different patterns of burning. Although longitudinal, these data suggest that temporal variability in aboveground plant biomass declines with diversity–stability mechanisms that underlie ecosystem function. Our results also support a decades-old principle of range management: moderate grazing intensity enhances diversity and stability, which has been shown to buffer forage shortfalls during drought.
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Mugunga, C. P., and D. T. Mugumo. "Acacia sieberiana Effects on Soil Properties and Plant Diversity in Songa Pastures, Rwanda." International Journal of Biodiversity 2013 (November 4, 2013): 1–11. http://dx.doi.org/10.1155/2013/237525.
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Effects of A. sieberiana trees on soil properties and plant diversity were investigated in Songa pastures, Rwanda. Tree characteristics and crown architecture of A. sieberiana were studied. Soil properties were assessed and plants were identified under and away from tree crowns. Counts of individual plants/species were done only under tree crowns. Nitrogen, P, and K were analysed in the soil, grass, and A. sieberiana leaves. Plant diversity was determined using Simpson's diversity index. Data were subjected to ANOVA. Soil organic carbon (SOC), cation exchange capacity (CEC), Ca2+, N and pH, and plant diversity were higher in soils under tree canopies than in open areas. Tree leaves were significantly richer in N and poorer in P and K as compared to grasses. Tree crowns grew wider and horizontal and developed intertwined secondary branching, reducing light intensity to as low as 38% under tree canopies compared to the open pasture. At 3 trees/ha stocking, A. sieberiana trees shaded 0.18 ha and herbaceous plants and grasses unpalatable to livestock dominated under tree canopies. A tradeoff of A. sieberiana tree value versus the loss of palatable grass due to tree presence needs to be assessed to decide whether the trees should be included in pastures and if yes, the apporpriate stocking identified.
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Swanepoel, P. A., J. Habig, C. C. du Preez, P. R. Botha, and H. A. Snyman. "Biological quality of a podzolic soil after 19 years of irrigated minimum-till kikuyu–ryegrass pasture." Soil Research 52, no. 1 (2014): 64. http://dx.doi.org/10.1071/sr13237.
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Conversion of natural rangeland to minimum-tillage kikuyu (Pennisetum clandestinum) based pastures for dairy production in the southern Cape of South Africa, may be beneficial to soil biological quality. The objective was to evaluate whether 19 years of minimum-till kikuyu-ryegrass pasture had altered the distribution and quality of biological properties formerly developed under natural rangeland. An irrigated minimum-till kikuyu-ryegrass pasture soil was compared to virgin soil with natural rangeland. Soil organic matter, soil organic C, active C, microbial biomass C, total N and enzymatic activities (β-glucosidase, urease and alkaline phosphatase) behaved similarly by having higher values in the surface layers of the cultivated pasture soil than in virgin soil, decreased with depth until they become similar at the 200–300 mm depth. Acid phosphatase activity was similar (P > 0.05) between soils. Vertical distribution of potentially mineralizable N was similar (P > 0.05) at 0–100 mm soil depth, but higher (P ≤ 0.01) in the cultivated pasture soil than in the virgin soil. The microbial indicated along with stratification ratios for different biological indicators that the cultivated pasture soil’s ecosystem functionality improved. Soil microbial functional diversity and carbon source utilisation patterns of the cultivated pasture soil and virgin soil was influenced by plant species present and root exudate composition. The soil microbial diversity, as shown by the Shannon-Weaver and Enrichment Indices, was significantly altered between cultivated pasture and the virgin soil, especially at different soil depths. A general appraisal of biological soil properties indicated that conversion of natural fynbos vegetation to irrigated minimum-till kikuyu-ryegrass pasture after 19 years of cultivation on a podzolic soil beneficial.
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Kumar, Akshay, and R. Verma. "Phytosociological Studies in Alpine Pasture of Tikkagahar, District Mandi, Himachal Pradesh." Journal of Non Timber Forest Products 26, no. 3 (September 1, 2019): 117–21. http://dx.doi.org/10.54207/bsmps2000-2019-sd4t47.
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A study was carried out to know the status of plant diversity in the alpine pasture of Tikkagahar, district Mandi, Himachal Pradesh during the year, 2017. A total of 75 plant species belonging to 31 families and 66 genera were recorded from the study area. Out of 59 medicinal plant species recorded from the pasture, two species viz; Roscoea alpina and Selinum vaginatum fall in the category of threatened plants. The distribution pattern of most of plant species was contiguous.
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White, Hannah J., Willson Gaul, Dinara Sadykova, Lupe León-Sánchez, Paul Caplat, Mark C. Emmerson, and Jon M. Yearsley. "Land cover drives large scale productivity-diversity relationships in Irish vascular plants." PeerJ 7 (May 31, 2019): e7035. http://dx.doi.org/10.7717/peerj.7035.
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The impact of productivity on species diversity is often studied at small spatial scales and without taking additional environmental factors into account. Focusing on small spatial scales removes important regional scale effects, such as the role of land cover heterogeneity. Here, we use a regional spatial scale (10 km square) to establish the relationship between productivity and vascular plant species richness across the island of Ireland that takes into account variation in land cover. We used generalized additive mixed effects models to relate species richness, estimated from biological records, to plant productivity. Productivity was quantified by the satellite-derived enhanced vegetation index. The productivity-diversity relationship was fitted for three land cover types: pasture-dominated, heterogeneous, and non-pasture-dominated landscapes. We find that species richness decreases with increasing productivity, especially at higher productivity levels. This decreasing relationship appears to be driven by pasture-dominated areas. The relationship between species richness and heterogeneity in productivity (both spatial and temporal) varies with land cover. Our results suggest that the impact of pasture on species richness extends beyond field level. The effect of human modified landscapes, therefore, is important to consider when investigating classical ecological relationships, particularly at the wider landscape scale.
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Gifford, Amy LS, Jean-Baptiste Ferdy, and Jane Molofsky. "Genetic composition and morphological variation among populations of the invasive grass, Phalaris arundinacea." Canadian Journal of Botany 80, no. 7 (July 1, 2002): 779–85. http://dx.doi.org/10.1139/b02-063.
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Species that become invasive after being introduced into a new range often experience genetic bottlenecks and strong selection to adapt to their new environment. We looked for evidence of such processes in unmanaged populations of invasive reed canary grass (Phalaris arundinacea L.). This grass species is planted as a forage crop in North America but has also invaded wetland areas. We compared isozyme variation in pasture and wetland populations of this species. We did not find any indication of a genetic bottleneck: wetland populations comprised as much diversity as pasture populations and both had as much diversity as the two cultivated varieties of reed canary grass that we sampled. We also cultivated plants from wetland and pasture populations and estimated genetic variance for several morphological traits. We did not find any significant differentiation to suggest differential selection between populations from the two habitats. In fact, we found the highest amount of genetic diversity, both isozymic and quantitative, within populations. We also found strong evidence that reed canary grass reproduces primarily clonally. The implications of these observations in terms of the origin of invasive populations of reed canary grass are discussed.Key words: invasive species, Phalaris arundinacea, reed canary grass.
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Mills, Aaron, and M. Sina Adl. "The effects of land use intensification on soil biodiversity in the pasture." Canadian Journal of Plant Science 86, Special Issue (December 1, 2006): 1339–43. http://dx.doi.org/10.4141/p06-114.
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A long-term multidisciplinary study of pasture agroecology is currently being conducted in Nova Scotia, Canada. The objective is to examine the relationship between above -ground and below-ground functional diversity, and the effects on agroecosystem productivity. The experimental design consists of four treatments of decreasing land use intensity, applied in the context of management intensive grazing. Treatments include: (1) clipping and harrowing following each grazing rotation (intensive); (2) clipping only once following the first defoliation; (3) grazing every second rotation; (4) grazed only once a year (extensive). Samples were taken from each treatment once during May, July, and September 2005. Edaphic characteristics and plant diversity were measured, as well as microarthropod, nematode, protist, and bacterial functional group diversity and abundances. Significant (P < 0.05) effects of treatment were observed on percentage of bare soil, plant species and functional diversity, and bacterial functional diversity. There were also significant (P < 0.05) negative correlations observed between treatment, and both testate amoebae and flagellate abundances. The information obtained from this study may be used to test the relationship between biodiversity and land-use intensity, and how productivity is affected in the pasture. Key words: Soil ecology, pasture management, sustainable agriculture, biodiversity, forage grazing
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Verma, R., Vaneet Jishtu, K. Kapoor, and Surinder Kumar. "Plant diversity in alpine pasture of Talra wildlife sanctuary of district Shimla, Himachal Pradesh." Indian Journal of Forestry 31, no. 1 (March 1, 2008): 13–18. http://dx.doi.org/10.54207/bsmps1000-2008-comt61.
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Studies to evaluate the plant diversity and growth forms in alpine pasture of Talra Wildlife Sanctuary of District Shimla, Himachal Pradesh were carried out during August, 2003. Total 75 species of plant, comprising of 7 grasses, 4 sedges, 4 leguminous forbs and 60 non-leguminous forbs were recorded from the area. On the basis of Importance Value Index (IVI). Sibbaldia cuneata O. Ktze., was found to be the dominant species followed by Geum elatum Wall ex D. Don., Ligularia amplexicaulis DC., Primula denticulata Smith and Saxifraga parnassifolia D. Don. The distribution of all the plant species was contagious. Index of dominance was 0.036 and index of diversity 5.386. The contribution of tall forbs, short forbs and cushioned and spreading forbs in the alpine pasture was 29.33%, 54.66% and 16.0% respectively.
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Kaur, K., R. K. Jalota, D. J. Midmore, and J. Rolfe. "Pasture production in cleared and uncleared grazing systems of central Queensland, Australia." Rangeland Journal 27, no. 2 (2005): 143. http://dx.doi.org/10.1071/rj05012.
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Clearing land of trees and introducing exotic pastures to enhance pasture and cattle production and hence enterprise financial performance are widely practised in Queensland. The results from many previous studies on tree clearing have emphasised the gains in pasture production, but over periods of less than 10–15 years after clearing. The present study questioned the sustainability of pasture production in cleared systems over a longer time-frame (>10 years of clearing). For this, three different age groups of clearing i.e. 5 year, 11–13 year and 33 year were selected in each of 3 major types of tree communities i.e. Eucalyptus populnea, E. melanophloia and Acacia harpophylla in central Queensland. Paired comparisons of cleared and uncleared (intact) pasture systems were selected for each age group of clearing. The results suggest that the initial gains in pasture production upon clearing were compatible with published studies. However, for longer periods of time since clearing, the gains in pasture production were not sustained and were accompanied by risks of land degradation and loss of pasture plant diversity. For E. populnea and A. harpophylla, the maximum benefits from clearing were achieved at 13–15 years whereas for E. melanophloia, any benefits existed only over a short period of 5–6 years. The study emphasises that each tree community exhibits a specific response with regard to the duration of increased pasture production following clearing. To estimate the total benefits from tree clearing in pasture development, it is important to consider both monetary benefits and non-monetary losses from clearing for different types of tree communities.
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Sangha, Kamaljit K., David J. Midmore, John Rolfe, and Rajesh K. Jalota. "Tradeoffs between pasture production and plant diversity and soil health attributes of pasture systems of central Queensland, Australia." Agriculture, Ecosystems & Environment 111, no. 1-4 (December 2005): 93–103. http://dx.doi.org/10.1016/j.agee.2005.05.007.
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Nyameasem, John Kormla, Carsten S. Malisch, Ralf Loges, Friedhelm Taube, Christof Kluß, Iris Vogeler, and Thorsten Reinsch. "Nitrous Oxide Emission from Grazing Is Low across a Gradient of Plant Functional Diversity and Soil Conditions." Atmosphere 12, no. 2 (February 6, 2021): 223. http://dx.doi.org/10.3390/atmos12020223.
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Nitrous oxide (N2O) emissions from pastures can vary significantly depending on soil and environmental conditions, nitrogen (N) input, as well as the plant’s ability to take up the N. We tested the hypothesis that legume-based N sources are characterized by significantly lower emission factors than mineral N based dairy systems. Therefore, this study monitored N2O emissions for a minimum of 100 days and up to two growing seasons across a gradient of plant species diversity. Emissions were measured from both grazed pastures and a controlled application of urine and dung using the static chamber method. About 90% of the simulated experiments’ accumulated N2O emissions occurred during the first 60–75 days. The average accumulated N2O emissions were 0.11, 0.87, 0.99, and 0.21 kg ha−1 for control, dung, urine patches, and grazed pastures, respectively. The N uptake efficiency at the excreta patch scale was about 70% for both dung and urine. The highest N2O-N emission factor was less than half compared with the IPCC default (0.3 vs. 0.77), suggesting an overestimation of N2O-N emissions from organically managed pastures in temperate climates. Plant diversity showed no significant effect on N2O emission. However, functional groups were significant (p < 0.05). We concluded that legume-containing pasture systems without a fertilizer addition generally appear capable of utilizing nitrogen inputs from excreta patches efficiently, resulting in low N2O emissions.
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Whitton, Maria M., Xipeng Ren, Sung J. Yu, Tieneke Trotter, Dragana Stanley, and Yadav S. Bajagai. "Remediation of Pasture Dieback Using Plant Growth Promotant." Agronomy 12, no. 12 (December 12, 2022): 3153. http://dx.doi.org/10.3390/agronomy12123153.
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Pasture dieback is a syndrome of unknown cause affecting grasses in Australia, creating significant economic losses to farmers by reducing available livestock feed and paddock carrying capacity. RC3 is a commercial plant growth stimulant tri-sodium salt of trimercapto-S-triazine (TMT) and potassium humate as active ingredients. TMT is commonly used for soil and wastewater remediation by capturing and binding heavy metals, while potassium humate is an organic compound used as a plant growth promoter. We investigated the ability of RC3 to restore soil health and productivity under pasture dieback conditions. RC3 was applied on pasture dieback affected paddock replicate plots once, at a rate of 4 mL/m2, and soil core samples were taken weekly to analyse microbial communities. Plants were collected regularly to measure dry matter and plant morphometrics. Twenty weeks after a single application, dry matter increased in RC3 plots by 900 kg/ha compared to control plots, and at week 48, eleven months after the single application, RC3 plots showed a trend of more grass and dicot species than the control. Morphometric measures suggest minor improvements in dicotyledon plants. Alpha diversity did not change with the application of RC3. Temporal correlation analysis shows that RC3 steadily reduced the presence of genera predominant in poor soils and with extreme environmental conditions over time and prevented the decline of beneficial genera, such as Marmoricola, Actinomadura, Dactylosporangium, and mle1-7.
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ÖZASLAN PARLAK, Altıngül, Ahmet GÖKKUŞ, and Hasan Can DEMİRAY. "Soil Seed Bank and Aboveground Vegetation in Grazing Lands of Southern Marmara, Turkey." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 39, no. 1 (May 30, 2011): 96. http://dx.doi.org/10.15835/nbha3915844.
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The composition and conservation of plant communities is greatly influenced by the soil seed bank. Information on the soil seed banks and the remaining vegetation in these ecosystems is crucial for guiding the restoration efforts. This study examines the size, species richness, diversity, uniformity, and similarity of soil seed banks and aboveground vegetation in 6 different grazing lands including coastal pasture, reseeded pasture, artificial pasture, lowland shrubland, ungrazed pasture, and hillside shrubland. Forty-eight soil samples were taken by cores with a diameter and depth of 10 cm from each of grazing lands in August of 2007. A vegetation survey was conducted using a 0.5 x 0.5-m quadrant in both the spring and fall. Eighty species were observed in soil seed banks and aboveground vegetation. The largest seed bank was observed in reseeded pasture (7,715 seed/m2), while the smallest seed bank was found in coastal pasture (2,755 seed/m2). Coastal pasture also possessed the least amount of aboveground vegetation (131 plants/m2). The most aboveground vegetation was found in ungrazed pasture (155 plants/m2). The most common species in seed banks were annual and perennial grasses in reseeded pasture, annual forbs in artificial pasture and hillside shrubland, and perennial forbs in low shrubland and ungrazed pasture. Species richness, diversity, and uniformity in seed banks were highest in lowland shrubland and lowest in artificial pasture. The seed bank and aboveground vegetation were similar in ungrazed pasture, coastal pasture, reseeded pasture, low shrubland, hillside shrubland and artificial pasture. Shrublands play an important role in species richness and the number of germinated seeds from seed banks of grazing lands in southern Marmara. The results showed that reseeding or a decrease in grazing pressure may improve the condition of grazing lands.
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Smith, R. W., C. A. Harris, K. Cox, D. McClements, S. G. Clark, Z. Hossain, and A. W. Humphries. "A history of Australian pasture genetic resource collections." Crop and Pasture Science 72, no. 9 (2021): 591. http://dx.doi.org/10.1071/cp20336.
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The introduction of exotic pasture germplasm has formed the foundation of many Australian grazing systems. Scientists have searched the world for plants to improve the feedbase, amassing collections of diverse genetic material, creating genebanks that have made a large contribution to feedbase productivity. These genebanks contain a vast range of legumes, grasses, herbs and shrubs with growth habits ranging from small herbaceous plants to woody trees and life cycles from annuals to short- and long-term perennial plants. They have been collected from cool temperate to tropical climates and arid to high-rainfall zones. Hundreds of cultivars have been developed from material either collected by Australian plant breeders overseas or introduced from overseas genebanks. The collection of this germplasm has enabled plant breeders to extend the area of adaptation of species into climates, soils and systems previously considered marginal. The importance to Australian and world agriculture is increasing as plant breeders seek traits to meet the challenges of a changing climate and animal production systems. Furthermore, urbanisation, landscape degradation and political instability are making it increasingly difficult to collect pasture and forage germplasm from native grasslands in many countries. This emphasises the need to maintain and improve the capacity of the Australian Pastures Genebank (APG). The APG houses ~85000 accessions and is a modern, online source of diversity for plant scientists around the world. This paper summarises the history of the founding genebank collections, their environment and farming systems focus, and the visionary and resourceful individuals that built them.
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Kemp, D. R., W. McG King, A. R. Gilmour, G. M. Lodge, S. R. Murphy, P. E. Quigley, P. Sanford, and M. H. Andrew. "SGS Biodiversity Theme: impact of plant biodiversity on the productivity and stability of grazing systems across southern Australia." Australian Journal of Experimental Agriculture 43, no. 8 (2003): 961. http://dx.doi.org/10.1071/ea02200.
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The relationships between productivity and plant species diversity were assessed using data from the Sustainable Grazing Systems (SGS) 10 national experiment sites. Each site applied up to 7 different management treatments. Sites varied in the amount of data available for analysis. Plant species diversity was assessed in terms of both the total and native species present at each site. More than 200 plant taxa were recorded over the period of the experiment, about one-third of which were native. In the majority of cases, the native species present within a treatment remained there throughout the experiments, even when fertilised and oversown with introduced species. The number of native species increased by 1 or 2 over the 3–4 years of each experiment where grasslands were less intensively used (average herbage mass >2 t DM/ha), but decreased in more heavily grazed treatments. Native grasses made much greater contributions to herbage mass than other native species. Of the more than 70 native plant species found, the most numerous were broadleaf species, which tended to be more variable under management treatments. As total species richness increased, there was a tendency for pasture productivity to be less, for the mean standing herbage mass to be less and for seasonal growth to be less stable. This depended upon experiments and tended to apply at the sites with higher annual pasture growth rates. All treatments had >10 plant species within the small (about 1.5 ha) paddocks used and larger paddocks often had many more. It was apparent from the high plant species richness at each site (about 25–100 species) that many more niches exist in these paddocks than the number of species usually sown in a pasture. Opportunities to redesign pasture mixtures to exploit more of the resources available obviously exist. Understanding of the relationships among management practices, productivity and plant species diversity is limited, but will become important as we seek more sustainable grazing systems. The studies analysed here suggested that where the herbage mass was maintained between 2 and 4 t DM/ha then species were maintained and productivity was optimised.
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Kutt, A. S., and J. E. Kemp. "Native plant diversity in tropical savannas decreases when exotic pasture grass cover increases." Rangeland Journal 34, no. 2 (2012): 183. http://dx.doi.org/10.1071/rj11048.
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The invasion of exotic plants into savanna ecosystems can disrupt the natural pattern of vegetation. Indian couch Bothriochloa pertusa was introduced into Australia as a species for rehabilitation of degraded grazing land. In this study the effect of increasing B. pertusa cover on native plant diversity and possible mechanisms of its spread were examined. Forty sites were sampled in uncleared Queensland rangelands with a range of B. pertusa and Bothriochloa ewartiana (a native species) cover. The mean number of native species per quadrat declined with increasing B. pertusa cover but remained stable over sites with increasing B. ewartiana cover. Mean species richness accumulated at a significantly lower rate for sites with B. pertusa present. Canonical analysis of principle coordinates suggested that three groups of sites, ranging from low to high species richness and cover of native plants, were correlated along gradients of B. pertusa cover, grazing intensity and basal area of dead trees. Generalised linear modelling indicated significant negative relationships between B. pertusa cover and total ground cover, forbs and perennial grass richness and cover, and cover of nine native perennial tussock grasses (Aristida leptopoda, B. decipiens, B. ewartiana, Chrysopogon fallax, Dichanthium fecundum, D. sericeum, Heteropogon contortus, H. triticeus and Themeda triandra). This study suggests that an increase in B. pertusa is associated with a substantial change in the cover and species richness of native plant communities. This was considered to occur via competitive effects as well as a result of cattle grazing, rainfall deficit and tree death. Regardless of the mechanism, continued spread of exotic pasture species has the potential to cause significant changes to rangeland biodiversity.
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Tracy, Benjamin F., Ian J. Renne, Jim Gerrish, and Matt A. Sanderson. "Effects of plant diversity on invasion of weed species in experimental pasture communities." Basic and Applied Ecology 5, no. 6 (December 2004): 543–50. http://dx.doi.org/10.1016/j.baae.2004.08.007.
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Austrheim, Gunnar, and Ove Eriksson. "Recruitment and life-history traits of sparse plant species in subalpine grasslands." Canadian Journal of Botany 81, no. 2 (February 1, 2003): 171–82. http://dx.doi.org/10.1139/b03-010.
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Recruitment is critical for the maintenance of plant populations and community diversity, but sexual regeneration is considered to be infrequent in climatically harsh habitats such as subalpine grasslands. This study examines the importance of regeneration through seed for 16 sparse herb species, and we asked whether their populations are limited by safe sites or the availability of seeds. Seedling recruitment and winter survival were recorded after sowing in an experimental split-plot design in (i) pasture grazed by livestock, and (ii) exclosed grassland cultivated for annual mowing. In addition we examined the effect of disturbance and local seedbank recruitment. All species were able to recruit and survive the first winter in at least some of the experimental plots, although none were initially present. Recruitment mainly occurred in disturbed plots, and disturbed pasture plots had a significantly higher recruitment than disturbed exclosures for all species except Silene dioica. We further examined whether specific plant traits were related to variation in recruitment. Lower recruitment in the disturbed exclosure was associated with higher specific leaf area, leaf dry weight, and seed number. In contrast, seeds sown in disturbed pasture recruited more independently of species traits. The exception was a negative correlation between recruitment and leaf dry weight, and an unexpected negative correlation with seed weight. We suggest that recruitment differences among habitats mainly reflect lower humidity in the exclosure. Consequently, small stature plants with small specific leaf area should have the highest recruiting probability when exposed to drought. The almost exclusive recruitment on disturbed plots indicates a strong competitive effect on the target species in vegetated plots, and suggests that safe sites for regeneration through seed are rare in subalpine grasslands.Key words: colonization, herbs, plant abundance and distribution, disturbance, pastures, cultivated exclosures, sowing experiment.
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Pinto, Alexandrede S., Mercedes M. C. Bustamante, Maria Regina S. S. da Silva, Keith W. Kisselle, Michel Brossard, Ricardo Kruger, Richard G. Zepp, and Roger A. Burke. "Effects of Different Treatments of Pasture Restoration on Soil Trace Gas Emissions in the Cerrados of Central Brazil." Earth Interactions 10, no. 1 (January 1, 2006): 1–26. http://dx.doi.org/10.1175/ei146.1.
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Abstract Planted pastures (mainly Brachiaria spp) are the most extensive land use in the cerrado (savannas of central Brazil) with an area of approximately 50 × 106 ha. The objective of the study was to assess the effects of pasture restoration on the N dynamics (net N mineralization/nitrification, available inorganic N and soil N oxide gas fluxes—NO and N2O), C dynamics (CO2 fluxes and microbial biomass carbon), and diversity of the soil bacterial community using denaturing gradient gel electrophoresis (DGGE) profiles. Sampling was done monthly on a farm in Planaltina, Goiás, Brazil (15°13′S, 47°42′W) from November 2001 to April 2002. Three areas of cerradão (dense cerrado) were converted to pasture (Brachiaria brizantha) in 1991, and after 8 years degradation was evident with the decreasing plant biomass production. Methods to restore these pastures were investigated for their sustainability, principally their effects on trace gas emissions. The pastures have been managed since 1999 as follows: 1) fertilized plot (N = 60 kg ha−1 yr−1, P = 12 kg ha−1 yr−1); 2) grass–legume plot, Brachiaria associated with a legume (Stylosanthes guianensis) with addition of P (12 kg ha−1 yr−1); and 3) a traditional plot without management. A fourth area of cerradão was converted to pasture in 1999 and was not managed (young pasture). Ammonium was the predominant inorganic N form in the soils (∼76 mg N kg−1) for all treatments throughout the study. In December 2001 a reduction in average soil N-NH4+ was observed (∼30 mg N kg−1) compared to November 2001, probably related to plant demand. All plots had high variability of soil N gases emissions, but during the wet season, the NO and N2O soil fluxes were near zero. The results of the water addition experiment made during the dry season (September 2002) indicated that the transition of dry to wet season is an important period for the production of N gases in the fertilized pasture and in the young pasture. Soil CO2 fluxes also increased after the water addition and the grass–legume plot had the highest increase in soil respiration (from ∼2 to 8.3 μmol m−2 s−1). The lowest values of soil respiration and microbial biomass carbon (∼320 mg C kg−1 soil) tended to be observed in the young pasture, because the superficial layer of the soil (0–10 cm) was removed during the conversion to pasture. Trace gas emissions measured after the water addition experiment corresponded to rapid changes in the soil bacterial community. The young pasture sample showed the lowest level of similarity in relation to the others, indicating that the bacterial community is also influenced by the time since conversion. This study indicates that the restoration technique of including Stylosanthes guianensis with B. brizantha increases plant productivity without the peaks of N oxide gas emissions that are often associated with the use of N fertilizers. Additionally, the soil bacterial community structure may be restored to one similar to that of native cerrado grasslands, suggesting that this restoration method may beneficially affect bacterially mediated processes.
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Kurz, Peter. "Management Strategies and Landscape Diversity in Commonly Governed Mountain Pastures: A Case Study from Austrian Alps." European Countryside 5, no. 3 (September 1, 2013): 212–31. http://dx.doi.org/10.2478/euco-2013-0014.
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AbstractThe paper explores the relationships between alpine pasture management and pastoral landscape ecosystems, based on research set in the Austrian limestone Alps. The focus of inquiry is laid upon the different management practices employed by pasturing communities. Therefore, the concept of “farming styles”, as introduced by Ploeg (1994) is adapted. Five different types of alpine pasture management could be identified. Those types are investigated further on their impacts on natural environments of vegetation- and landscape patterns, taking diversity of plant communities as an indicator. It is figured out that management strategies as a central factor shaping diversity in mountain pastureland shall be considered in the design of agro-environmental policies and in nature conservation.
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Moussa, Loukmane, Ibouraïma Yabi, and Ismaïla Toko Imorou. "Diversité Floristique Et Usages Des Ligneux Le Long Des Couloirs De Transhumance Dans La Commune De Savè Au Centre Bénin." European Scientific Journal, ESJ 13, no. 2 (January 31, 2017): 400. http://dx.doi.org/10.19044/esj.2017.v13n2p400.
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The vegetation cover of the District of Savè is subject to continuous pressure linked inter alia to the cutting of wood, agriculture and livestock through transhumance. Thus, forage seedlings are regularly used mainly during the dry season by transhumant herds. In this context, the characterization of woody pastures and the study of the uses of its timber by the local populations is a major imperative for their preservation and sustainable management. To this end, socio-economic surveys were carried out among the stakeholders involved in the use of these plant resources. The phytosociological surveys (29 plots of 30 m * 30 m) were carried out using the sigmatite method of Braum blanquet. Different indices have been calculated. The graph of the raw and weighted spectra was carried out. The characterization of the structure of the pasture shows a predominance of the individuals of circumference of between 30 and 50 cm. Mesophanerophytes are the most abundant and dominant forms of life, while chronologically Sudanese and Sudano-Zambeze species are the most represented. The most represented families are the combretaceae the leguminoseae. The Shannon diversity index varies from 3.21 to 3.95 bits and the Piélou equitability from 0.72 to 0.83 from one pasture to another. Three (3) types of pasture were identified along transhumance corridors. Namely: the pasture at Lannea velutina and Bridelia ferruginea; Pasture in Trichilia emetica and Annona senegalensis and grazing in Pteleopsis suberosa and Pericopsis laxiflora. This study shows that the environmental conditions favor the installation of several species along the transhumance corridors. The uses of forage resources, such as pruning for feeding livestock, charcoal making, fuelwood research, particularly in transhumance corridors, are not likely to Conservations
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GHIMIRE, SURESH KUMAR, DOYLE MCKEY, and YILDIZ AUMEERUDDY-THOMAS. "Himalayan medicinal plant diversity in an ecologically complex high altitude anthropogenic landscape, Dolpo, Nepal." Environmental Conservation 33, no. 2 (June 2006): 128–40. http://dx.doi.org/10.1017/s0376892906002943.
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The conservation of high-altitude medicinal plants is of concern throughout the Himalayan region, because they are important for traditional health care and in large-scale collection for trade. Because little is known regarding their conservation status in relation to the diversity of land-use patterns and habitats, this paper explores patterns of species composition and diversity of medicinal plants in five different pasture types in a traditionally-managed high-altitude landscape in northwest Nepal. Environmental variables, including human activities, strongly affected species composition, diversity and cover-abundance of medicinal plant species. Species richness of rare and commercially threatened medicinal plants (CTMP) showed patterns similar to overall medicinal plant species richness. Sub-alpine meadows, which have intermediate levels of human pressure related to grazing and relatively high levels of resource availability in terms of rainfall and soil nutrients, were richer in medicinal-plant species than alpine meadows. The coexistence of various plant communities under different human management regimes also enhanced landscape-level species diversity by maintaining some species restricted to particular habitat or pasture types. A number of medicinal plant species reported to be resistant to grazing were most abundant in heavily grazed sites. This pattern suggests that medicinal plant species may be positively influenced, to a certain extent, by human activities (mainly grazing). The combination of grazing and high levels of harvesting, however, had a negative impact on diversity and cover-abundance of rare and CTMP species. Maintenance of medicinal plant diversity and cover-abundance is critically dependent on managing grazing and resource harvesting to maintain levels that are both ecologically and economically sustainable. Forage for livestock and medicinal plants for local health care cannot be managed independently; a systems approach is needed, incorporating social management to accommodate the needs of different users. This could be achieved by maintenance of a mosaic landscape, in which different use patterns and pressures, reflecting the values attached to resources by different users and favouring different types of biodiversity, co-exist.
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Schon, N. L., P. M. Fraser, and A. D. Mackay. "Relationship between earthworm abundance, ecological diversity and soil function in pastures." Soil Research 59, no. 8 (2021): 767. http://dx.doi.org/10.1071/sr20273.
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Earthworms contribute to a wide range of process that underpin soil function and ecosystem services and are an important component of a soil’s natural capital stocks. With increasing interest in soil health, it is important to better understand the type of earthworm community required to enhance soil functions. This is of particular interest in New Zealand where pasture systems are dominated by exotic earthworm species and low ecological diversity. Two separate mesocosm experiments were established to explore the interaction between earthworm abundance and ecological diversity as it influences soil functions. Experimental increases in earthworm abundance increased soil macroporosity and water infiltration, increased plant nitrogen (N) and plant growth. Although some benefits were observed at the lowest earthworm abundances, the greatest benefits were seen at the higher abundances. Earthworm ecological diversity is also critical to ensure soil functions are optimised. For example, the single species of Aporrectodea caliginosa alone was not able to improve water infiltration or pasture production. However, when this species was found in combination with Aporrectodea longa, there was positive influence on soil functions despite the abundance of A. longa itself not increasing. This study highlights the importance of including a measure of ecological diversity alongside a measure of abundance to assess soil biological health.
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Belgeri, Amalia, Ali Ahsan Bajwa, Asad Shabbir, Sheldon Navie, Gabrielle Vivian-Smith, and Steve Adkins. "Managing an Invasive Weed Species, Parthenium hysterophorus, with Suppressive Plant Species in Australian Grasslands." Plants 9, no. 11 (November 16, 2020): 1587. http://dx.doi.org/10.3390/plants9111587.
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Parthenium weed has been invading native and managed Australian grasslands for almost 40 years. This study quantified the potential of selected plant mixtures to suppress the growth of parthenium weed and followed their response to grazing and their impact upon plant community diversity. The first mixture consisted of predominantly introduced species including Rhodes grass, Bisset bluegrass, butterfly pea and green panic. This mixture produced biomass rapidly and showed tolerance to weed species other than parthenium weed. However, the mixture was unable to suppress the growth of parthenium weed. The second mixture of predominantly native pasture species (including forest bluegrass, Queensland bluegrass, Buffel grass and siratro) produced biomass relatively slowly, but eventually reached the same biomass production as the first mixture 12 weeks after planting. This mixture suppressed parthenium weed re-establishment by 78% compared to the control treatment. Its tolerance to the invasion of other weed species and the maintenance of forage species evenness was also superior. The total diversity was five times higher for the mixture communities as compared to the plant community in the control treatment. Therefore, using the suppressive pasture mixtures may provide an improved sustainable management approach for parthenium weed in grasslands.
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Zhao, Jiantao, Jiamin Cao, Zhaobi Che, Yaya Guo, Chunhui Ma, and Qianbing Zhang. "Contribution of Sheep Grazing to Plant Diversity in Natural Grasslands." Diversity 14, no. 6 (June 2, 2022): 446. http://dx.doi.org/10.3390/d14060446.
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Global climate change and overgrazing have led to the degradation of natural grasslands and seriously threaten the diversity of grassland plant species, as plant species richness is very sensitive to natural grassland degradation. Therefore, we conducted a sheep grazing experiment in Zinniquan pasture on the northern slope of Xinjiang Tianshan Mountains to test the effects of grazing on plant species diversity in natural grasslands through the spatial and temporal characteristics of the foraging behavior of grazing sheep and the plant species composition on the grazing trajectories. Data on sheep grazing tracks were collected based on GPS, vegetation composition around the tracks was investigated and seeds were collected from sheep manure to determine germination rates by simulating rumen fistula uptake tests in sheep. We found that sheep grazing can bring seeds from agricultural fields to grow on natural grasslands, causing changes in plant species diversity and community structure. The results of this study provide new insights into natural grassland species restoration and offer a range of new strategies that can be applied to the management of natural grassland plant ecological restoration.
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Dullinger, Stefan, Thomas Dirnböck, Josef Greimler, and Georg Grabherr. "A resampling approach for evaluating effects of pasture abandonment on subalpine plant species diversity." Journal of Vegetation Science 14, no. 2 (February 24, 2003): 243–52. http://dx.doi.org/10.1111/j.1654-1103.2003.tb02149.x.
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Murphy, D. V., W. R. Cookson, M. Braimbridge, P. Marschner, D. L. Jones, E. A. Stockdale, and L. K. Abbott. "Relationships between soil organic matter and the soil microbial biomass (size, functional diversity, and community structure) in crop and pasture systems in a semi-arid environment." Soil Research 49, no. 7 (2011): 582. http://dx.doi.org/10.1071/sr11203.
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The quantity and/or quality of soil organic matter (SOM) and its fractions regulate microbial community composition and associated function. In this study an established, replicated agricultural systems trial in a semi-arid environment was used to test: (i) whether agricultural systems which have increased plant residue inputs increase the amount of labile SOM relative to total SOM, or change the quality of SOM fractions; and (ii) whether the size or quality of OM fractions is most strongly linked to the size, activity, functional diversity, and community structure of the soil microbial biomass. Soil (0–50 mm) was collected following 5 years of continuous wheat, crop rotation, crop–pasture rotation, annual pasture, or perennial pasture. Pastures were grazed by sheep. Direct drilling and non-inversion tillage techniques were compared in some cropping systems. Total carbon (C) increased with the proportion of pasture as a result of increased SOM inputs into these systems; land use also significantly affected SOM fractions and their chemical and physical nature. While the size, function, and structure of the soil microbial community were somewhat related to total soil C, they were better correlated with SOM fractions. The C : nitrogen (N) ratio of light fraction organic matter could be used to predict the amount of potentially mineralisable N in soil, while the C : N ratio of total SOM could not. Measurement of bacterial community structure (using denaturing gradient gel electrophoresis) significantly discriminated between land uses, while community-level physiological profiles revealed fewer differences. Overall, our findings support the premise that labile fractions of SOM are more strongly related to microbial community structure and function than is total SOM.
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Bebawi, Faiz F., Shane D. Campbell, and Robert J. Mayer. "Can competition with pasture be used to manipulate bellyache bush (Jatropha gossypiifolia L.) population biology?" Rangeland Journal 35, no. 4 (2013): 393. http://dx.doi.org/10.1071/rj13011.
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Bellyache bush (Jatropha gossypiifolia L.) is an invasive weed that poses economic and environmental problems in northern Australia. Competition between pasture and bellyache bush was examined in North Queensland using combinations of five pasture treatments (uncut (control); cut as low, medium, and high pasture; and no pasture) and four bellyache bush densities (0, 2, 6 and 12 plants m−2) in a buffel grass (Cenchrus ciliaris L.) dominated pasture. The pasture treatments were applied approximately once per year but no treatments were applied directly to the bellyache bush plants. Measurements of bellyache bush flowering, seed formation, and mortality were undertaken over a 9-year period, along with monitoring the pasture basal cover and plant species diversity. Maximum flowering rates of bellyache bush occurred after 9 years (97%) in plots containing no pasture, with the lowest rates of 9% in uncut control plots. Earliest flowering (322 days after planting) and seed formation (411 days) also occurred in plots with no pasture compared with all other pasture treatments (range 1314–1393 days for seed formation to occur). No seeds were produced in uncut plots. At the end of 9 years, mortality rates of bellyache bush plants initially planted averaged ≥73% for treatments with some pasture compared with 55% under the no-pasture treatment. The percentage of herbaceous plant basal cover in uncut plots was increased 5-fold after 9 years, much greater than the average 2% increase recorded across the low, medium, and high pasture treatments. The number of herbaceous species in uncut plots remained largely unchanged, whereas there was an average reduction of 46% in the cut pasture treatments. Buffel grass remained the species with the greatest basal cover across all cut pasture treatments, followed by sabi grass (Urochloa mosambicensis (Hack.) Dandy) and then red Natal grass (Melinis repens (Willd.) Ziska). These results suggest that grazing strategies that maintain a healthy and competitive pasture layer may contribute to reducing the rate of spread of bellyache bush and complement traditional control techniques such as the use of herbicides.