Academic literature on the topic 'Undesirable Species'
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Journal articles on the topic "Undesirable Species"
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Kumar, Rakesh. "Controlling Undesirable Algal Species From Aquatic Ecosystems." International Journal on Algae 25, no. 4 (2023): 383–88. http://dx.doi.org/10.1615/interjalgae.v25.i4.60.
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Control of undesirable algal species is the primary requirement for the long-term maintenance of health of an aquatic ecosystem. Their excessive growth may cause ecosystem imbalance by depleting the water quality and affecting the life of aquatic fauna. The present paper describes the physical, chemical and biological methods of controlling undesirable algal species.
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KIRKMAN, L. KATHERINE, ROBERT J. MITCHELL, MELANIE J. KAESER, STEPHEN D. PECOT, and KIMBERLY L. COFFEY. "The perpetual forest: using undesirable species to bridge restoration." Journal of Applied Ecology 44, no. 3 (April 10, 2007): 604–14. http://dx.doi.org/10.1111/j.1365-2664.2007.01310.x.
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Winkler, Jan, Markéta Ježová, Radek Punčochář, Erika Hurajová, Petra Martínez Barroso, Tomáš Kopta, Daniela Semerádová, and Magdalena Daria Vaverková. "Fire Hazard: Undesirable Ecosystem Function of Orchard Vegetation." Fire 6, no. 1 (January 11, 2023): 25. http://dx.doi.org/10.3390/fire6010025.
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Fires will become an increasingly frequent perturbation even under the conditions of the mild climate zone and will interfere with the agricultural landscape. Fire is a natural phenomenon, and depending on ecosystems, vegetation may develop and contribute to the occurrence and spread of fire. Vegetation of the sour cherry orchard located in the climatically dry conditions of the South Moravian Region, Czech Republic (CR), was evaluated. Vegetation assessment was performed using phytocenological relevé. In each variant, 10 relevé were recorded. Coverage of the found species was estimated directly in percentages. Moreover, the maximum height in the stand was measured for each type of plant. Biomass of individual plant species was calculated, using the biomass index (IB) equation. The IB values of individual plant species in the treatments were processed by employing a multidimensional analysis of the ecological data. Different vegetation management practices in an orchard change the species diversity of the vegetation and thus the fire hazards in the orchard conditions. Grassy interrow has the most grass biomass during the entire vegetation season, and therefore represents the greatest hazard and spread of fire. The most important grasses include Arrhenatherum elatius, Dactylis glomerata, Festuca pratensis, Lolium perenne, and Poa pratensis. On the contrary, bare soil conditions in the interrow are most suitable for annual species, and this is the place with the highest changes in the number of species during the growing season. Biomass of the orchard vegetation combined with dry and warm weather increases the fire hazard. Annual and perennial grasses have very good potential for the production of biomass, which increases the hazard of fire. The nature of the vegetation in the orchards has the potential for the actual start of a fire and its subsequent spread, however, under other environmental conditions. During hot and dry weather, dead biomass may accumulate resulting in increasing the hazard of large wildfires. Varied orchard management practices lead to a higher diversity of vegetation and make orchards, islands of biodiversity in the agricultural landscape.
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Jaskuła, Radomir, Anna Sulikowska-Drozd, Aleksandra Jabłońska, Krzysztof Banaś, and Tomasz Rewicz. "Undesirable immigrants: hobbyist vivaria as a potential source of alien invertebrate species." PeerJ 7 (September 17, 2019): e7617. http://dx.doi.org/10.7717/peerj.7617.
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Background Small size and large diversity of adaptations make invertebrates a group of animals which can be easily transported by different human activities. Many species can travel as “hitchhikers” with plant material (both on plant surfaces and in the soil), including plants used for decoration in vivaria. Vivaria are often tropical in nature environments, with high temperatures and humidity, suitable for invertebrates from tropical regions. Although many of such invertebrates cannot survive in temperate regions where harsh weather conditions are present, it is also known that some can successfully acclimatise. As a result, their negative impact on local flora and fauna cannot be excluded. Material and methods Terrestrial invertebrates were collected in several cities of Poland from tropical vivaria where poison dart frogs (Dendrobatidae) and/or orchids (Orchidaceae) were kept by hobbyists. Collecting of the material was preceded by a simple questionnaire placed on the biggest Polish forum devoted to poison dart frogs. Moreover, we contacted some Polish wholesalers offering tropical invertebrates (Isopoda and Collembola), used as the food source for frogs, hoping to receive information about locations where those invertebrates were delivered, over the period of one year. We obtained mtDNA barcodes using the COI marker (cytochrome c oxidase subunit I gene) for seven potential morphospecies. Results In total, 12 taxa classified as Turbellaria, Annelida, Gastropoda, Isopoda, Diplopoda, Chilopoda and Collembola were collected and preserved in pure ethanol. We collected material and/or information from 65 locations, including 56 cities to which exotic isopods and springtails were sold by wholesalers over the period of nine months (average number per month = 18 cities). We obtained 18 COI sequences which were assigned to seven BINs and thus confirmed identification of seven species. The results indicate that the number of species transported with exotic plants is not small and can be observed regularly. Species noted as “hitchhikers” on plant structures and/or as inhabitants of soil in plant pots, originally came from South and Central America, Africa, Asia and possibly from North America or Southern Europe. Three taxa were noted for the first time from Poland, including Rhynchodemus sylvaticus (Rhynchodemidae), Trichorhina sp.1 (Platharthridae), and Guppya gundlachi (Euconulidae). Discussion The presented study clearly shows that an exotic hobby such as keeping tropical poison dart frogs and/or orchids may promote fast and uncontrolled dispersion of a high number of invertebrates classified in different taxonomical groups. Plant material (green elements of plants and the soil in which they are planted) used in vivaria can be an important source of such animals.
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Veskovic-Moracanin, Slavica, Dragica Karan, Dragan Milicevic, and Aleksandra Stjepanovic. "The presence of undesirable mould species on the surface of dry sausages." Zbornik Matice srpske za prirodne nauke, no. 114 (2008): 97–103. http://dx.doi.org/10.2298/zmspn0814097v.
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Transition from manufacture to the industrial way of meat production and processing, as well as contemporary concept of food quality and safety, have led to the application of starter cultures. Their application leads towards the streamlining of the production process in the desired direction, quality improvement and its harmonization, and thereby to its standardization. Application of moulds in the meat industry is based on positive effects of their proteolytic and lipolytic egzoenzymes which, as a consequence, leads to the creation of characteristic sensory properties ('flavor') of fermented products. Penicillium nalgiovense is a typical representative of moulds used in the production of fermented sausages-salamis from our region. Samples of 'zimska salama' (dry sausage), produced with Penicillium nalgiovense, were evaluated as hygienically unacceptable. Their sensory properties changed due to contamination of this mould during the ripening process. Micological analysis discovered the presence of Penicillium aurantiogriseum, which is a frequent mould contaminant in the meat industry. At the same time, thin layer chromatography revealed no possibility of metabolic activity of this mould in the creation of mycotoxins. However, the presence of this mould on the surface of 'zimska salama' is considered as undesirable due to formation of 'off flavor' in products. Such product is considered as hygienically unacceptable and cannot be used for the human consumption.
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Loftis, David L. "Preharvest Herbicide Treatment Improves Regeneration in Southern Appalachian Hardwoods." Southern Journal of Applied Forestry 9, no. 3 (August 1, 1985): 177–80. http://dx.doi.org/10.1093/sjaf/9.3.177.
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Abstract Preharvest herbicide treatment of undesirable and unmerchantable vegetation was compared to postharvest felling. Ten years after the clearcut harvesting, the preharvest treatment had increased the number and proportion of desirable stems and decreased the number and proportion of undesirable sprouts in the dominant stand. Stands that developed after the preharvest herbicide treatment are dominated by single-stemmed desirable species, and excellent future stocking is assured. Because of the presence of undesirable sprout clumps, plots receiving the postharvest felling have an uncertain future. An effective preharvest treatment that costs about the same as postharvest felling is recommended.
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Lim, Haw Chuan, Navjot S. Sodhi, Barry W. Brook, and Malcom C. K. Soh. "Undesirable aliens: factors determining the distribution of three invasive bird species in Singapore." Journal of Tropical Ecology 19, no. 6 (October 24, 2003): 685–95. http://dx.doi.org/10.1017/s0266467403006084.
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Biological invasions are a major environmental concern due to their negative impacts on biodiversity and economics. We determined the population sizes and habitat-abundance relationships of the three most successful invasive bird species in Singapore: the house crow Corvus splendens, white-vented myna Acridotheres javanicus and common myna A. tristis. Estimated population sizes of the three species between February 2000 and February 2001 were between 106 000-176 000, 122 000-155 000 and 20 000-29 000, respectively. Population size of the house crow grew dramatically (>30-fold) in the last 15-16 y while that of the white-vented and common myna declined. Habitat-abundance relationships suggest that house crows are highly dependent on anthropogenic food. Their abundance was also positively related to proximity to coast. The common myna associated closely with agricultural areas while the white-vented myna probably preferred urban greenery among residential buildings. Our study shows that the three invasive bird species associated with different aspects of human-modified environment.
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Glasenapp, Cattò, Villa, Saracchi, Cappitelli, and Papenbrock. "Promoting Beneficial and Inhibiting Undesirable Biofilm Formation with Mangrove Extracts." International Journal of Molecular Sciences 20, no. 14 (July 19, 2019): 3549. http://dx.doi.org/10.3390/ijms20143549.
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The extracts of two mangrove species, Bruguiera cylindrica and Laguncularia racemosa, have been analyzed at sub-lethal concentrations for their potential to modulate biofilm cycles (i.e., adhesion, maturation, and detachment) on a bacterium, yeast, and filamentous fungus. Methanolic leaf extracts were also characterized, and MS/MS analysis has been used to identify the major compounds. In this study, we showed the following. (i) Adhesion was reduced up to 85.4% in all the models except for E. coli, where adhesion was promoted up to 5.10-fold. (ii) Both the sum and ratio of extracellular polysaccharides and proteins in mature biofilm were increased up to 2.5-fold and 2.6-fold in comparison to the negative control, respectively. Additionally, a shift toward a major production of exopolysaccharides was found coupled with a major production of both intracellular and extracellular reactive oxygen species. (iii) Lastly, detachment was generally promoted. In general, the L. racemosa extract had a higher bioactivity at lower concentrations than the B. cylindrica extract. Overall, our data showed a reduction in cells/conidia adhesion under B. cylindrica and L. racemosa exposure, followed by an increase of exopolysaccharides during biofilm maturation and a variable effect on biofilm dispersal. In conclusion, extracts either inhibited or enhanced biofilm development, and this effect depended on both the microbial taxon and biofilm formation step.
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Krieg, Randon J., and W. T. Witte. "EFFICACY OF A COPPER HYDROXIDE/LATEX PAINT FORMULATION FOR ROOT - PRUNING 41 SPECIES OF CONTAINERIZED NURSERY STOCK." HortScience 28, no. 5 (May 1993): 527f—527. http://dx.doi.org/10.21273/hortsci.28.5.527f.
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The root system of containerized nursery stock may become undesirably coiled or matted on the outer surface of the media. Various copper formulations painted on the interior of the container surface have been shown to control undesirable root growth in a few species. We tested a commercial formulation of 100 g/l copper hydroxide in a flowable latex paint formulation (SpinOut™) on 41 tree, shrub, and herbaceous species. Plants were grown 4 months in 7.5×7.5×15cm containers, either treated or untreated. Root density was evaluated on a scale of 1 to 5 (no roots on the surface to heavy rooting). Analysis showed treated containers prevented roots from growing on the media surface in all species tested except Magnolia liliiflora `Jane', Buxus sempervirens `Vardar Valley', and Taxus × media `Hicksii', where control of surface rooting was significant but moderate. Copper paint did not inhibit growth of stolons or rhizomes, which morphologically are stem structures. No visual signs of copper toxicity were observed, nor were there any differences in shoot growth.
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Robertson, Bruce C., Graeme P. Elliott, Daryl K. Eason, Mick N. Clout, and Neil J. Gemmell. "Sex allocation theory aids species conservation." Biology Letters 2, no. 2 (January 10, 2006): 229–31. http://dx.doi.org/10.1098/rsbl.2005.0430.
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Supplementary feeding is often a key tool in the intensive management of captive and threatened species. Although it can increase such parameters as breeding frequency and individual survival, supplementary feeding may produce undesirable side effects that increase overall extinction risk. Recent attempts to increase breeding frequency and success in the kakapo Strigops habroptilus using supplementary feeding inadvertently resulted in highly male-biased chick sex ratios. Here, we describe how the inclusion of sex allocation theory has remedied this conservation dilemma. Our study is the first to manipulate chick sex ratios in an endangered species by altering maternal condition and highlights the importance of incorporating evolutionary theory into modern conservation practice.
Dissertations / Theses on the topic "Undesirable Species"
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Ungerer, James L. "Effects of prescribed burning on undesirable plant species and soil physical properties on tallgrass prairies." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16909.
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Master of ScienceDepartment of Agronomy
Walt Fick
Prescribed burning has been a common conservation practice on native prairie dating back to the days of pioneer settlement. Advantages include increased forage quality, reduction of undesirable plants, improved wildlife habitat, removal of accumulated dead plant litter and relatively low costs. While spring is the commonly accepted time to burn, little research has been conducted on late-summer and fall burning for specific objectives that include targeting undesirable plant species and measuring potential effects on soil physical properties. The first part of this study was to evaluate the effect that prescribed burning has on population dynamics of sericea lespedeza (Lespedeza cuneata [Dumont] G. Don), rough-leaf dogwood (Cornus drummondii Meyer), and additional woody species. Stem counts and cover estimates were taken from 20, 0.25-m[superscript]2 frames prior to and post-burn. Change in botanical composition, plant density, frequency, and Daubenmire canopy cover estimates were calculated. Sericea lespedeza plant frequency across all clay upland burns decreased 2.27% and increased 4.76% across all loamy/limy upland burns the first growing season post-burn. Dogwood densities increased 3.12 stems m[superscript]-[superscript]2 on spring burns compared to a decrease of 0.30 stems m[superscript]-[superscript]2 on unburned plots the first growing season post-burn. Changes in frequency of other woody species the first growing season post-burn showed significant interactions between burn treatment and ecological site, and between ecological site and year. A significant interaction between burn treatment and ecological site was found on total woody species plant composition changes two growing seasons post-burn for the first year of burn treatments. The secondary part of this study was to evaluate the effect of prescribed burning on soil bulk density and wet-aggregate stability. Soil samples were collected along the same line-transects used for vegetation sampling. Significant differences among mean weight diameters (MWD), percent water-stable aggregates (WSA), and WSA size fractions occurred between burned and unburned soils following burning in the fall of 2011. Monitoring plant and soil response to prescribed burning in different seasons may lead to adjustments being made in management of rangelands where sericea lespedeza, dogwood, and additional woody species occur.
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Byenkya, Gilbert Steven. "Impact of undesirable plant communities on the carrying capacity and livestock performance in pastoral systems of south-western Uganda." Texas A&M University, 2003. http://hdl.handle.net/1969.1/255.
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The impact of undesirable plant communities (Cymbopogon afronardus and woody species dominated by Acacia species) on livestock carrying capacity and performance was investigated on 15 farms in an Acacia/Cymbopogon dominated pastoral system of south-western Uganda. Species prevalence based on basal cover for grasses, frequency for forbs and effective canopy cover for trees/shrubs were determined on farms. The PHYGROW model was used to predict forage productivity for computation of carrying capacity. The NIRS/NUTBAL nutritional management system was used to determine cattle dietary CP and DOM through fecal scans and to estimate animal performance.
Cymbopogon afronardus had a prevalence of 10.29% among the grasses while Acacia gerrardii (34.37%) and Acacia hockii (33.66%) were the most prevalent woody species. Forage productivity differed significantly among the farms with a mean long-term annual forage yield of 4560(SE+41) kg/ha. Farms infested with Cymbopogon and woody species produced the least amount of forage and therefore had the lowest carrying capacities (0.38 -0.39 AU/ha) while improved farms had comparatively higher forage yields with higher carrying capacities (0.49 - 0.52 AU/ha). A mean carrying capacity for the system was estimated at 0.44 AU/ha using a 25% harvest efficiency for ANPP. All the farms were overstocked, on average by 3.2 times.
Livestock BCS, diet CP and DOM were significantly different (P<0.0001) among the different farm types. BCS were highest on improved farms and lowest on Cymbopogon infested farms while dietary CP and DOM values were lowest on improved farms and highest on farms with a high woody component. Farms with a relatively high woody component exhibited intermediate BCS despite the high dietary CP values. Cattle on Cymbopogon infested farms had consistently lower body weights over the months although there were no significant differences in daily live weight gains among farms.
Recommendations included need for research into appropriate control measures for both Cymbopogon afronardus and woody species, farmer sensitization about overstocking, research to improve forage quality on improved farms and need for feed supplementation for improved breeds on improved farms. Integration of NIRS/NUTBAL and PHYGROW models into the research and management systems was desirable. The observed increase in Sporobolus spp. required investigation.
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Rocher, Léo. "Identification des paramètres de la végétation favorisant les arthropodes bénéfiques et les fonctions écologiques associées en viticulture : approche corrélative et expérimentale." Electronic Thesis or Diss., Avignon, 2024. http://www.theses.fr/2024AVIG0375.
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Le déclin de la biodiversité dans les agroécosystèmes est largement attribué à l'essor de l'agriculture moderne. Les principales causes sont la destruction des structures semi-naturelles, l’extension de la taille des parcelles agricoles et l'utilisation intensive d'intrants. Les arthropodes jouent un rôle important dans l’amélioration de services écosystémiques essentiels tels que la régulation des ravageurs et la pollinisation. Pour favoriser leur présence, la végétation est un facteur primordial. En effet, les plantes fournissent des ressources alimentaires cruciales et permettent la création d’habitats pour les arthropodes. Pour favoriser ces organismes dans les agroécosystèmes et restaurer les fonctions écologiques associées, des pratiques telles que l'introduction de structures semi-naturelles sont pertinentes. Dans des cultures permanentes comme les vignobles, de telles structures peuvent être implantées à l’intérieur des parcelles. En région méditerranéenne, la gestion des inter-rangs de vigne implique souvent l'élimination de la végétation non-cultivée pour des raisons de compétition hydrique et pour contrôler les espèces végétales considérées comme nuisibles. Ces travaux de thèse visent à mieux comprendre comment la végétation des inter-rangs peut favoriser la présence d'arthropodes bénéfiques et la fonction de prédation mais limiter la prolifération des espèces végétales nuisibles en viticulture méditerranéenne (Luberon, France). Trois questions principales de recherche se sont posées : (1) La présence de l’enherbement et sa composition floristique influencent-elles la présence des fourmis, actrices importantes de la fonction de prédation dans les vignes ? (2) Quels groupes fonctionnels de la végétation sont reliés à l’abondance des arthropodes prédateurs et pollinisateurs ainsi que la fonction de prédation ? (3) Est-ce qu’un enherbement diversifié et local augmente la présence d’arthropodes bénéfiques, améliore la fonction de prédation et limite l’installation des espèces végétales problématiques ? Dans un premier chapitre nous avons étudié la réponse des fourmis à l’enherbement dans 23 vignobles. Les fourmis jouent un rôle crucial dans la prédation des vignobles méditerranéens (Luberon, France). Nous avons testé l’effet de trois modes de gestion de la végétation sur la diversité et fréquence des fourmis : des inter-rangs enherbés, partiellement enherbés et non enherbés. Nous avons montré que les vignobles partiellement enherbés présentaient une plus grande richesse de fourmis comparé à ceux non-enherbés. Le recouvrement en graminées et la présence de plantes pérennes ont influencé positivement la richesse de fourmis, suggérant l'importance de prendre en compte ces facteurs dans la gestion de la végétation. Dans le second chapitre, nous avons examiné quelles caractéristiques de la végétation spontanée influencent les arthropodes bénéfiques et la fonction de prédation sur 37 vignobles. Nous avons constaté que le recouvrement en fleurs nectarifères et la richesse en espèces végétales favorisaient la plupart des groupes d'arthropodes bénéfiques, ainsi que la fonction de prédation. Ces résultats soulignent l'importance des ressources florales et de la diversité végétale pour favoriser la présence des arthropodes étudiés. Enfin, le dernier chapitre est consacré à une expérimentation de semis et de son suivi sur deux ans. Trois types d’enherbements sont comparés : un semis haute diversité, la végétation spontanée et des inter-rangs sans végétation. En accord avec le deuxième chapitre, nos résultats soulignent les effets positifs de la richesse végétale et du recouvrement en fleurs sur le contrôle des mauvaises herbes, l'abondance des arthropodes bénéfiques et la fonction de prédation. L’ensemble des résultats de ces travaux de thèse convergent et mettent en lumière l’importance de considérer différents paramètres de la végétation pour favoriser les arthropodes bénéfiques en viticultureBiodiversity decline within agroecosystems is mainly attributed to modern agriculture. The main causes include the destruction of semi-natural structures, the increase in field size and the high use of agrochemicals for fertilisation and pest control. Arthropods contribute significantly to the key ecosystem services such as pest control and pollination. They largely depend on the vegetation within fields and in the surroundings. Plants provide food resources and other habitat functions that are crucial for the survival and reproduction of arthropods. Semi-natural structures are important to maintain species-rich vegetation, and thus arthropods with associated ecological functions. In permanent crops such as vineyards, semi-natural structures can be established in inter-rows within fields. However, in the French Mediterranean, inter-rows are often tilled to remove non-crop vegetation since winegrowers are afraid of water competition and the spread of undesirable weeds. This thesis aims to better understand how inter-row vegetation promotes beneficial arthropods and predation of pest insects while limiting the spread of undesirable plant species in Mediterranean vineyards of South-Eastern France (Luberon). The present thesis addresses three major research questions: (1) Do inter-row vegetation cover and its floristic composition affect ant species and diversity, that were found to be vineyard predators? (2) Which functional groups of the vegetation are related to the abundance of predators, parasitoids, pollinators and predation sentinel prey? (3) Does species-richinter-row vegetation increase the abundance of such beneficial arthropods, improve predation of sentinel prey and limit the spread of undesirable plant species? In the first chapter, we studied the ant response to inter-row vegetation in 23 vineyards. We tested the effects of three types of inter-row vegetation management on ant diversity and frequency: fully, partially, and non-vegetated vineyards. We showed that partially vegetated vineyards had greater ant species richness compared to non-vegetated ones. Grass and perennial plant cover positively influenced ant species richness, demonstrating the importance of inter-row vegetation and itsmanagement. In the second chapter, we examined which characteristics of spontaneous vegetation affect beneficial arthropods and sentinel prey predation in 37 vineyards. We found that nectariferous flower cover and plant species richness favoured most groups of beneficial arthropods, as well as predation. These results underline the importance of floral resources and plant diversity in promotingthe studied beneficial arthropods. The last chapter focuses on a sowing experiment that was analysed for two years. Three types of inter-row vegetation were compared: high diversity sowing, spontaneous vegetation, and inter-rows without vegetation. In agreement with the second chapter, our results highlight the positive effects of plant species richness and flower cover on weed control, beneficial arthropod abundance, and predation of sentinel prey. The overall results of the different studies conducted in this thesis converge and highlight the importance of considering vegetation characteristics to promote beneficial arthropods in vineyard ecosystems
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Free, Jennifer Lynelle. "Inherently Undesirable: American Identity and the Role of Negative Eugenics in the Education of Visually Impaired and Blind Students in Ohio, 1870-1930." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1353009941.
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Desrochers, Valérie. "Utilisation de microboutures de saule pour prévenir le développement d'espèces indésirables." Thèse, 2019. http://hdl.handle.net/1866/22741.
Full textBooks on the topic "Undesirable Species"
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Lewis, Polsgrove, ed. Reducing undesirable behaviors. Reston, Va: Council for Exceptional Children, 1991.
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Vanita, Ruth. The Dharma of Justice in the Sanskrit Epics. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780192859822.001.0001.
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This book examines how characters in the Mahabharata and the Ramayana debate questions of justice. The epics depict discrimination based on social categories such as gender, varṇa, species, age, and disability, and important characters often support discrimination. But the epics also criticize oppression in two ways—first, philosophically, through debates, and second, practically, through characters whose actions demonstrate that discrimination is wrong. Many characters in the epics (including men and women from all varṇas and those later considered outside the varṇa system) repeatedly proclaim the principle of sameness (samatva). All bodies are made of the same matter and are vulnerable, all consciousnesses are essentially the same, and all categories constantly change, and are ultimately unreal. This book considers debates about friendship and the family, about the meaning or non-meaning of varna and gender, about male–female interactions and the questions of consent, sex-change, gender-crossing, disability, and masculinities. The dharmas of singleness, marriage, friendship, parenting, and rulership, especially in relation to violence and non-violence, are explored, and Yudhishthira’s idea of complete non-violence is critiqued as impossible and undesirable. The book argues that kindness to animals is at the heart of the epics’ idea of universal dharma. Non-cruelty to animals is a dharma available to all humans, regardless of status. Approaching the epics as bhakti texts, the book concludes with an extended study of how bhakta poets of all persuasions, from Kabir and Raidas to Jnaneshwara, Rahim, and Tulsidas, draw their philosophical frameworks and ideas from the epics.
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Peach, Ken. Committee Meetings. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198796077.003.0010.
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This chapter concerns the structure, organization and conduct of a meeting, including the special role of the chair of the committee. Meetings are an essential tool for getting things done, although, used skilfully, they can also be used to block the undesirable or unachievable. As meetings of one sort or another are an essential part of research life, professional scientists should aspire to be as efficient in these more managerial aspects as they are in the research itself. In this chapter, the various founding documents of the committee (terms of reference, standing orders, etc.) are described. The organization of the agenda and the writing of the minutes are also discussed. In addition, some examples are given about how to deal with difficult issues in committee.
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Mittendorf, Martina. Legal Framework for Data Processing in Employee Fluctuation Risk Analysis – the European Regulation from a German Perspective. Technische Hochschule Wildau, 2021. http://dx.doi.org/10.15771/2824.
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In connection with the management of employee retention many Human Resources Managers feel the need to know who of their employees might leave the company in the near future. The more a company knows about the motives of those who might leave, the easier it is to get in contact with them. Thus it is not surprising that the HR Managers want to try to combine all the data they have or can get in order to predict the behavior of their employees. It is evident that the interpretation of data-combinations can give inaccurate predictions of the probability of departure of an employee, and it is undesirable for this data-interpretation process to create a negative image of an employee. It is a sensitive issue for all parties involved, because managers want to retain the “good people” and keep the company going; on the other hand many employees are afraid of having all details of their work be observed. The uncertainties can hopefully be best dealt with by talking with each other. However, it is worth taking a look at the European legal situation in order to determine if these analyses are permitted at all. Therefore it is necessary to examine whether and under what conditions an analysis of employee fluctuation risk is compatible with the GDPR, which has been applicable since May 25th, 2018, and which places special conditions on the processing of personal data in Europe.
Book chapters on the topic "Undesirable Species"
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Carter, Clifford W. "Management of Undesirable Native Plant Species." In Range Resources of the Southeastern United States, 35–40. Madison, WI, USA: American Society of Agronomy and Crop Science Society of America, 2015. http://dx.doi.org/10.2134/asaspecpub21.c4.
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Pyke, David A., and Chad S. Boyd. "Manipulation of Rangeland Wildlife Habitats." In Rangeland Wildlife Ecology and Conservation, 107–46. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34037-6_5.
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AbstractRangeland manipulations have occurred for centuries. Those manipulations may have positive or negative effects on multiple wildlife species and their habitats. Some of these manipulations may result in landscape changes that fragment wildlife habitat and isolate populations. Habitat degradation and subsequent restoration may range from simple problems that are easy to restore to complex problems that require multiple interventions at multiple scales to solve. In all cases, knowledge of the wildlife species’ habitat needs throughout their life history, of their population dynamics and habitat-related sensitivities, and of their temporal and spatial scale for home ranges and genetic exchange will assist in determining appropriate restoration options. Habitat restoration will begin with an understanding of the vegetation’s successional recovery options and their time scales relative to wildlife population declines. We discuss passive and active manipulations and their application options. Passive manipulations focus on changes to current management. Active manipulations may include removal of undesirable vegetation using manual harvesting, mechanical, chemical, or biological methods while desirable vegetation is enhanced through the reintroduction of desirable wildlife habitat structure and function. These techniques will require monitoring of wildlife and their habitat at both the landscape and site level in an adaptive management framework to learn from our past and improve our future management.
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Cappitelli, Francesca, and Federica Villa. "Novel Antibiofilm Non-Biocidal Strategies." In Microorganisms in the Deterioration and Preservation of Cultural Heritage, 117–36. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-69411-1_5.
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AbstractSubaerial biofilm (SAB) formation on cultural heritage objects is often considered an undesirable process in which microorganisms and their by-products, e.g., enzymes and pigments, cause damage or alteration to a surface. Since biofilms are widespread phenomena, there has been a high demand for preventive and control strategies that resist their formation or reduce their negative effects once formed. Up to date, the main strategy to control biofilms has been the use of biocides. Because of their intrinsic properties, biocidal products can pose risks to humans, animals, and the environment. In this chapter, the authors call “green” only those alternative strategies to biocides able to prevent/control biofilms but that do not kill microorganisms, i.e., irrespective of the use of natural compounds. Here, we describe some of the methods that are most commonly used to test the effectiveness of antibiofilm compounds with multiple-species biofilm model systems. A unified terminology and well described protocols and guidelines are still required to compare and test the effectiveness of traditional or novel compounds against biofilms retrieved on heritage surfaces.
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Lockwood, Julie L., and Dustin J. Welbourne. "Undesirable impacts." In Invasive Species: A Very Short Introduction, 64–77. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/actrade/9780198818281.003.0008.
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Abstract This chapter addresses the question of why impacts might be considered undesirable. It elaborates on the categories of economic, human health, and environmental impact. Invasive species often result in the loss of economic opportunities and ecosystem services. Meanwhile, invasive species also affect human health and wellbeing through the introduction and spread of infectious diseases and parasites. The chapter explains that any impact of invasive species is of environmental concern whether or not it is directly concerned with human health or the economy. To examine why environmental impacts are undesirable, concepts of environmental ethics are introduced. The chapter explores how different philosophical paradigms give rise to differing levels of concern for invasive species.
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Davis, Mark A. "Management of invasive species." In Invasion Biology, 132–60. Oxford University PressOxford, 2009. http://dx.doi.org/10.1093/oso/9780199218752.003.0008.
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Abstract Real and substantial threats to human health, great economic harm, and other undesirable ecological impacts have fueled efforts to manage the spread and impact of non-native species posing these threats. As is the case with most problems, there are two general approaches one can take to deal with these threats—prevention and mitigation.
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Lockwood, Julie L., and Dustin J. Welbourne. "Nature abhors a definition." In Invasive Species: A Very Short Introduction, 5—C2P14. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/actrade/9780198818281.003.0002.
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Abstract This chapter covers how defining invasive species is problematic, but a definition provides practical utility for steering research, evaluating new findings, and developing management responses. The definition of what is invasive centres on species being non-native and either causing an impact or spreading through a region. The chapter also explains what is and is not a native species, again demonstrating the difficulty of categorizing such entities, and how values underpin whether impacts are considered undesirable.
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Daniela Manzano Guzmán, Sandra, Jose Augusto Drummond, and Cristiane Gomes Barreto. "Undesirable Neighbours: Eucalyptus and Protected Areas." In Protected Area Management - Recent Advances [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99831.
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Eucalyptus is the common name of a set of exotic species present in the Brazilian territory. They have a strong invasive potential which is detrimental to the preservation of native floral formations, particularly in protected areas. This research seeks to (i) understand the stage of eucalyptus invasion in the Brasilia National Park; (ii) identify the main vectors of the invasive populations and (iii) verify the possible role of the adjoining Brasília National Forest in the invasion and (iv) consider possible conflicts between the roles of these two different categories of protected areas. A set of phytosociological sample areas were defined inside the park to pinpoint different eucalyptus populations. Findings indicate that eucalyptus populations inside the park behave invasively, having advanced 186.30 meters from their point of origin over the span of 45 years. Among the possible contamination vectors are a neighbouring nursery run by the local government and eucalyptus plantations in the adjoining Brasília National Forest. Results indicate the need for management actions to avoid continual seed dispersal by examined populations. They also indicate that the distinct conservation goals of national forests and national parks must be considered, especially when they are neighbours.
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Lockwood, Julie L., and Dustin J. Welbourne. "An ounce of prevention is worth a pound of cure." In Invasive Species: A Very Short Introduction, 78—C9F5. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/actrade/9780198818281.003.0009.
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Abstract This chapter tackles invasive species management as a response to the undesirable impacts of invasive species. The management strategies employed by most governments roughly follow the stages of the invasion process, and are referred to as prevention and eradication, containment, and resource protection. It is shown that the cost of management action increases as the population size of the invasive species increases and becomes more widespread. The chapter highlights the various methods used to manage biological invasions throughout the invasion process and how goals shift as invasive species become more common.
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Lockwood, Julie L., and Dustin J. Welbourne. "It is never simple." In Invasive Species: A Very Short Introduction, 92–100. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/actrade/9780198818281.003.0010.
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Abstract This chapter expounds on the complexities of understanding and managing invasive species, grouping them into three broad areas. First, the chapter looks at how different people weigh the desirability of impacts since a single non-native species might produce both desirable and undesirable impacts, depending on who evaluates the desirability. Second, the chapter highlights the difficulties when invasive species positively affect endangered species, or when the invasive species is itself endangered. Finally, the chapter concludes by examining how climate change adds a new dimension to understanding biological invasions.
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Davis, Mark A. "Impacts of invasions." In Invasion Biology, 101–31. Oxford University PressOxford, 2009. http://dx.doi.org/10.1093/oso/9780199218752.003.0007.
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Abstract Non-native species, like native species, can impact human health, national and local economies, and the ecosystems and ecological communities in which they reside. In fact, most non-native species do not have a large impact in any of these three areas. Some even have desirable effects. However, a small proportion of non-native species are considered harmful or undesirable owing to their impacts. In some instances, the harmful impacts can be dire. Introduced pathogens can threaten human health, crops, and livestock.
Conference papers on the topic "Undesirable Species"
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Yufereva, Nadezhda, and Maria Shchannikova. "SPECIES AND VARIETIES OF PERENNIAL GRASSES FOR MAKING OF STABLE LAWN COMMUNITIES." In Multifunctional adaptive feed production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2020. http://dx.doi.org/10.33814/mak-2020-22-70-59-64.
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The correct selection of species and varieties of perennial grasses for making of stable lawn herbages is an important task for the researchers. Research of lawn herbages was conducted for six years period on the experimental field of the Vyatka State Agricultural Academy. As a result, were specified domestic varieties of lawn grasses which suit for the conditions of the Kirov region and show resistance to adverse weather conditions observed during the years of research. Red fescue Sigma and meadow grass Vagant and Dar forming lawns from good to excellent quality. The number of shoots per unit area for the sixth year for these species and varieties is 12.6–15.9 thousand pieces per square meter, 6.5–6.8 thousand pieces per square meter and 4.1–5.0 thousand pieces per square meter respectively. These species and varieties can be recommended for making of stable single–species lawn herbages. The seeding rate can be reduced in comparison to the recommended one. Perennial ryegrass in the conditions of the Kirov region shows low winter hardiness, the number of shoots declines since the third year of life and the number of undesirable plant increases. However, the perennial ryegrass has superior lawns in the year of sowing. Therefore, this species can be used for the quick making of lawns with a usable life no more than two years.
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Sircar, Indraneel, Rohan Gejji, Anup Sane, David Blunck, Scott Meyer, and Jay P. Gore. "Design and Testing of a High Pressure and High Temperature, Optically Accessible, Entrained Flow Coal Gasifier." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44201.
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Improved understanding of coal gasification chemical kinetics is needed to increase thermodynamic efficiency and to reduce undesirable CO2 emissions. This work describes an optically-accessible entrained-flow coal gasifier designed and built to allow measurements of the major species at various stages of the chemical reactions. The 2-meter tall gasifier consists of five subsystems: the optical diagnostics, steam generator, coal feeder, external heaters, and gas sampling and analysis. A stoichiometric H2-O2 flame generates superheated steam, the gasifying agent, which reacts with pulverized coal fed from a variable feed-rate pressurized powder feeder. To sustain the endothermic coal gasification reaction, radiant heaters provide 15 kW of external heating. Diagnostics to determine the major species concentrations consist of tunable diode laser absorption spectroscopy (TDLAS) measurements within the reactor vessel assembly and analysis of dry product gases using a gas chromatograph.
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McCarthy, Larry, and Comas Haynes. "Steady and Pulsed Flow Performance Trends of Higher Concentration DMFCs." In ASME 2006 4th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2006. http://dx.doi.org/10.1115/fuelcell2006-97115.
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Direct methanol fuel cells (DMFCs) are a promising source of energy due to their potentially high energy density, facilitated fuel delivery and storage, and precluded fuel processing. However, DMFCs have several challenges which need to be resolved before they can replace existing energy sources. Some of these challenges include lower power density, relatively high cost, and uncertain reliability. These issues are all promoted, at least in part, by the methanol crossover phenomenon, wherein membrane permeability allows the undesirable species transport of methanol from the anode to the cathode. This phenomenon also causes the requirement of dilute fuel mixtures, which is undesirable from an energy density viewpoint. Prior research has shown that methanol crossover can be reduced by operating DMFCs in a transient mode [1,2]. Thus, a study has been performed to investigate the impact of hydraulic pulsing (HP) at different operating conditions, such as fuel concentration, current density, and number-of-stoichs (NOS). Furthermore, the cell’s performance is being characterized at different steady flow concentrations to highlight the impact of fuel dilution.
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Stanisavljević, Dragana, Dušica Ćirković, Violeta Mickovski Stefanović, and Dragan Veličković. "HEMIJSKI SASTAV I SENZORNE KARAKTERISTIKE RAKIJA OD VOĆA." In XXVII savetovanje o biotehnologiji. University of Kragujevac, Faculty of Agronomy, 2022. http://dx.doi.org/10.46793/sbt27.509s.
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In addition to the main ingredients, ethanol and water, fruit brandies contain a small amount of a large number of secondary ingredients, which give these drinks specific organoleptic characteristics. Among these ingredients, there are also those that are harmful and undesirable, so the goal of the producer is to reduce their content as much as possible. In order to examine the quality of brandy, a chemical analysis and sensory evaluation of brandy obtained from different fruit species were performed. The content of ethanol and other parameters was within the limits expected for the tested brandies, and in accordance with the applicable law.
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Jansone, Baiba, Edgars Dubrovskis, and Linards Sisenis. "INFLUENCE OF TREE SPECIES MIXTURE TO REDUCE WIND DAMAGES IN BIRCH STANDS." In GEOLINKS International Conference. SAIMA Consult Ltd, 2020. http://dx.doi.org/10.32008/geolinks2020/b2/v2/07.
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Climate change is linked to increase in frequency and/or severity of different damages in forest stands. Birch (Betula spp.) stands can be significantly affected by wind and snow (freezing rain). Aim of our study was to assess, if admixture of other tree species reduces the proportion of damaged trees in birch stands. Data from total of 836 sample plots (size 500m2) in birch stands at the age of up to 81 year were analysed. Among the mixed sands (MS) and pure stands (PS >80% of single tree species), the mean proportion (± confidence interval) of damage was assessed from the total number (TN) and basal area (BA) of overstory (first layer) trees. MS were further assessed in two groups – one or more species in admixture (MS+1 and MS+2). The proportion of mixed birch stands was increasing with age: from average of 21% at the age of up to 20 years to 64% at the age of 61-70 years, most likely do to difference in historical management. In period between the 1950th and 1990th, birch was considered as undesirable species and the older stands formed mainly due to low survival of coniferous trees and natural ingrowth of birch, whereas starting from the 1990th birch was more widely recognized and used as target species. Proportion of undamaged birch trees (both, when assessed as TN or BA) was not significantly different between MS and PS. Also presence of second layer trees did not affect the proportion of damaged overstory trees significantly. There were significant differences among the groups of mixed stands: more wind or snow damaged trees were found in certain age groups in stands with more than one admixture species present. Creating a mixed birch stands in comparison to pure stands of the same tree species may not result in lower frequency of damaged trees, thus this approach cannot be automatically recommended as a tool for adaptation to climate change
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Lazaridi, Eleni, and Boudewijn Hollebrands. "Selective ionization of oxidized versus non-oxidized lipid species using different solvent additives in direct infusion MS." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/uvqo5522.
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Lipid oxidation in food products is a crucial problem that causes undesirable changes in the food’s flavor, texture, nutritional value and consequently reduces shelf life. Even though lipid oxidation has been examined extensively and is rather well understood in bulk oils and fats, the processes behind it in more complex systems like emulsified foods are still largely unresolved. Oxidation reactions are believed to progress from the oil/water interface to the core of the oil droplets, making it important to understand the contribution of interfacial lipids (i.e. MAG, DAG and PL) to the lipid oxidation process. To study this, novel analytical tools are needed that allow the characterization of the highly complex mixture of oxidized species encountered in aged emulsified foods.In this study, a direct infusion mass spectrometry (MS) approach was set up to selectively ionize oxidized lipid species versus their non-oxidized precursors (DAG and TAG). Three mobile phase additives were investigated (NH4HCO2, C2H3NaO2 and NaI) at three different concentrations, and three ion source parameters (i.e. sheath gas temperature, nozzle and capillary voltage)were optimized. A fractional factorial design was conducted to examine not only the direct effect of the operating parameters on selective ionization of oxidized lipid species, but also assess their combined effect. A three level process was chosen to examine the effect of the selected parameters: (1) on the whole mass range of oxidized versus non oxidized lipid species, (2) on selected lipid species and their different oxidized forms, and (3) on the fragments of the lipid species investigated in the previous step. Selective ionization of oxidized versus non-oxidized lipid species was favored more by the use of sodium containing solvent additives. These findings will contribute to future studies on the influence of interfacial composition on lipid oxidation in complex emulsified food systems.
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Yarema, O. M., L. Ya Fedonyuk, E. I. Skyba, and A. Lesniak-Mochuk. "ANTHROPOGENIC ENVIRONMENTAL CHANGES DUE TO ACCUMULATION OF SOLID HOUSEHOLD WASTE IN TERNOPIL REGION (UKRAINE)." In SAKHAROV READINGS 2021: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2021. http://dx.doi.org/10.46646/sakh-2021-2-382-386.
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All over the world, the recycling and disposal of household waste are becoming an increasingly pressing issue. In the process of economic development of virgin lands, there was gradual destruction of natural ecosystems and their replacement by anthropogenic ones, the balance between certain species of flora and fauna was disturbed. This undesirable impact of labor on nature is especially evident at the present stage of human development, which is characterized by extremely rapid demographic growth and rapid scientific, technological, and socio-economic development of society. Population growth contributes to the growth of waste - substances, materials, and objects generated in the process of human activity, and have no further use at the place of formation or detection.
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Sun, Hong, Ying-ying Lin, Xi Geng, Lanka Wickramasinghe, Fulya Zalluhoglu, and Qing Wang. "Engineering a Synthetic Friction Reducer to Combat Undesirable Formation of FR-Metal Complex/Precipitation in Slickwater Fracturing." In SPE Hydraulic Fracturing Technology Conference and Exhibition. SPE, 2024. http://dx.doi.org/10.2118/217763-ms.
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Abstract During stimulation and production, a highly viscous and rubbery precipitation can form due to incompatibility of friction reducer polymers (cationic, anionic or amphoteric) with ferric ions, particularly in formations with high iron content. This material plugs up proppant packs, even production strings, and is extremely detrimental to well productivity. A straightforward sequestration approach with chelants does not work because of poor outcome and prohibitive economics. Compatible biopolymer FRs, as an alternative approach, have limited applications due to their moderate FR performance compared to synthetic PAM based polymers. This work shows the development of a novel synthetic friction reducer to address this challenge. The polymer was designed by systematically optimizing monomer compositions, molecular weight and surfactant packages. Friction reduction performance of the newly developed FR was evaluated in friction loops under various water conditions. Iron tolerance tests were performed by mixing ferric iron with prehydrated FRs under different pHs, at high concentrations, and salinities. The mixture solutions were then placed in a water bath for heat treatment to simulate downhole conditions and to accelerate the formation of the ferric/FR complexes. Comparative experiments were performed using conventional FRs. In order to probe the interaction between polymers and the iron species, zeta potential analyzer was applied to measure charge changes of the polymer strands. The newly developed FR showed superior FR performance with fast hydration and high overall friction reduction, in both fresh water and synthetic brines. In iron tolerance tests, rubbery precipitations formed in solutions for all three types of conventional FRs, while no such precipitations were observed with the newly developed FR, even in the presence of 500 ppm ferric ion. This test was repeated in a wide range of pH and salinity conditions and no significant viscosity change of the FR polymer solution was observed before and after the test. Zeta potential measurements confirmed the validity of the polymer design to minimize the interaction between the new FR polymer and iron ions. This paper demonstrates that the newly developed friction reducer successfully solves the incompatibility issue of FRs with iron spices, i.e., without flocculation on the surface or formation of gummy precipitations downhole. Its superior friction reduction performance with no concerns of potential damages make it a strong candidate for iron-rich fields. Mechanism of the interaction between iron and synthetic polymers is proposed and confirmed by zeta potential results. The manuscript discusses in depth the strategy of the design of the newly developed copolymer, including selection of monomers, molecular weight control, and inverting surfactants.
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Soares, Jennifer M., Vanderlei S. Bagnato, and Kate C. Blanco. "Synergistic enhancement effects of antibiotic combination with photodynamic inactivation." In Latin America Optics and Photonics Conference. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/laop.2022.w4a.29.
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Antimicrobial resistance is one of the most severe threats to global public health in this century. Photodynamic Inactivation (PDI) is an alternative to antibiotic therapy, a standard treatment for infections because the combination of a photosensitizer with light leads to the production of reactive oxygen species that promote eliminating undesirable cells without bacterial selection and with few side effects for the patient. This work investigates whether PDI can restore bacterial sensitivity to antibiotics. PDI protocols using curcumin and light at 450 nm are applied at regular intervals and new values of minimum inhibitory concentration of antibiotics are obtained. As a result, we observed that PDI treatments can decrease MIC. Thus, the combination of both antimicrobial therapies may result in synergistic effects.
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MAGARIO, Ivana, José SCILIPOTI, and Salvador Eduardo BRANDOLÍN. "ACTIVITY-BASED KINETIC MODELLING OF LIPASE CATALYSED SYNTHESIS OF PEROCTANOIC ACID." In SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE. DR. D. SCIENTIFIC CONSULTING, 2022. http://dx.doi.org/10.48141/sbjchem.21scon.12_abstract_brandolin.pdf.
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Carboxylic peroxy acids are organic oxidants of relevance in the cosmetic, food, and agrochemical industries. However, they are traditionally used as intermediaries in a process known as Prileschajew epoxidation and synthesized using sulfuric acid as a catalyst, promoting undesirable reactions on the final epoxides. Therefore, the study of selective catalysts such as enzymes is a topic of interest. In this work, peroctanoic acid synthesis was carried out using n-hexane as the solvent and an immobilized Candida Antarctica Lipase B commercial preparation as the catalyst. On the other hand, the oxidant, hydrogen peroxide was supplied as an aqueous solution, comprising the disperse phase of the reacting system. The reaction progression was quantified by iodometric and cerimetric titration of the peroctanoic acid concentration in the hexane phase. Four different initial amounts of octanoic acid were tested (0.74, 1.57, 10, and 20 millimoles). Substrate inhibition by octanoic acid was observed having at 1.57 millimoles the maximum initial reaction rate. The experimental data were fitted to a ping-pong bi-bi enzymatic kinetic model to estimate the initial reaction rate. Since this system constituted a liquid-liquid (organic-aqueous) two-phase system, the model was evaluated employing the thermodynamic activities of all species involved, assuming phase equilibria with time. The activities of all species were estimated using UNIFAC. As a result, the model was able to reproduce the trend of the initial rate with the change of the initial amount of octanoic acid.
Reports on the topic "Undesirable Species"
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Short, Mary, and Sherry Leis. Vegetation monitoring in the Manley Woods unit at Wilson’s Creek National Battlefield: 1998–2020. Edited by Tani Hubbard. National Park Service, June 2022. http://dx.doi.org/10.36967/nrr-2293615.
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Natural resource management at Wilson’s Creek National Battlefield (NB) is guided by our understanding of the woodlands and prairies at the time of the Civil War battle in 1861. This report is focused on the Manley Woods unit of the park. This unit is an oak-hickory woodland in the Springfield Plain subsection of the Ozarks. Canopy closure for Missouri oak woodlands can be highly variable and ranges from 30–100% across the spectrum of savanna, open woodland, and closed woodland types. In 1861, the woodland was likely a savanna community. Changes in land use (e.g., fire exclusion) caused an increase in tree density in woodlands at Wilson’s Creek NB and across the Ozarks. Savannas and open woodlands transitioned to closed canopy woodlands over time. Park management plans include restoring the area to a savanna/open woodland structure. Prescribed fire was reintroduced to Wilson’s Creek NB in 1988 and continues as the primary mechanism for reducing the tree canopy. The Manley Woods unit of Wilson’s Creek NB has been subject to intense natural and anthropogenic disturbance events such as a tornado in 2003, timber removal in 2005, prescribed fires in 2006, 2009, and 2019, an ice storm in 2007, and periodic drought. The Heartland Inventory and Monitoring Network (hereafter, Heartland Network) installed four permanent monitoring sites within the Manley Woods area of the park in 1997. Initially, we assessed ground flora and regeneration within the sites (1998–1999). We added fuel sampling after the 2003 tornado. Although overstory sampling occurred prior to the tornado, the protocol was not yet stabilized and pre-2003 overstory data were not included in these analyses. In this report, we focus on the overstory, tree regeneration, and ground cover metrics; ground flora data will be assessed in future analyses. Heartland Network monitoring data reveal that Manley Woods has undergone substantial change in canopy cover and midstory trees since 1998. While basal area and density metrics classify Manley Woods as an open woodland, the closed canopy of the midstory and overstory reveal a plant community that is moving toward closed woodland or forest structure. The most recent fire in 2019 was patchy and mild, resulting in continued increases in fuels. Ground cover metrics indicate infrequent disturbance since leaf litter continued to increase. Management objectives to restore savanna or woodland composition and structure to the Manley Woods overstory, regeneration layer, and ground cover will require implementation of prescribed fire in the future. Repeated fires can thin midstory trees and limit less fire tolerant early seral species. Additionally, mechanical or chemical treatments to reduce undesirable tree species should be considered for woodland restoration. Decreasing canopy closure is an important and essential step toward the restoration of a functioning savanna/open woodland plant community in Manley Woods. Treatments that thin the midstory and reduce fuel loading will also benefit these plant communities. With the anticipated changing climate, maintaining an open woodland community type may also provide resilience through management for native species tolerant of increasingly warmer temperatures.