Search results for: invasive alien species

Authors: Yashasvi Thakur, Vikas K. Sharma

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The fragile Himalayan ecosystems are sensitive to environmental stresses, including direct and indirect impacts of climate stresses. A total of 297 naturalized alien plant species belonging to 65 families in the IHR have already been reported. Of the total 297 naturalized alien plant species in IHR, the maximum species occur in Himachal Pradesh (232; 78.1%), followed by Jammu & Kashmir (192; 64.6%) and Uttarakhand (181; 60.90%). The present study reports the spread of some invasive and existing weed species like Ageratum conyzoides, Bidens pilosa, Chromolaena odorata, Lantana camara, Brossnetia papyrifera, Oxalis corniculata, Galinsoga parviflora, Panicum maximum at an extent that they are not only invading the agricultural fields but are also replacing the native plant species and degrading the existing grassland quality. Moreover, the degradation of grassland has led to the dry fodder shortage for livestock in the lower Shivalik ranges of the state of Himachal Pradesh and has also encouraged the use of herbicides at an extensive scale. This article provides a mapping of the current spread of some of these species at the block level to allow the development of appropriate management strategies and policy planning for addressing issues pertaining to plant invasion, agricultural fields, and grasslands across the IHR states.

Keywords: climate change, invasive alien species, agriculture, grassland, IHR

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Authors: Tomasz Raczyński

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Non-native and invasive species negatively transform ecosystems. Non-native fish species can displace native fish species through competition, predation, disrupting spawning, transforming ecosystems, or transmitting parasites. This influence is more and more noticeable in Poland and in the world. From December 2014 to October 2020, did catch of fishes by electrofishing method carried on 416 sites in various parts of Poland. Research was conducted in both running and stagnant freshwaters with the predominance of running waters. Only sites where the presence of fish was found were analysed. The research covered a wide spectrum of waters from small mountain streams, through drainage ditches to the largest Polish river - the Vistula. Single sites covered oxbow lakes, small ponds and lakes. Electrofishing was associated with ichthyofauna inventories and was mainly aimed at detecting protected species of fish and lampreys or included in the annexes to the EU Habitats Directive (Council Directive 92/43/EEC on the Conservation of natural habitats and of wild fauna and flora). The results of these catches were analysed for alien and invasive fish species. The analysis of the catch structure shows that in 71 out of 416 research sites was found alien and invasive fish species, belonging to 9 taxa. According to the above, alien species of fish are present in 17% of the study sites. The most frequently observed species was the Prussian carp Carassius gibelio, which was recorded on 43 sites. Stone moroko Pseudorasbora parva was found on 24 sites. Chinese sleeper Perccottus glenii was found on 6 sites, and Bullhead Ameiurus sp. was also found on 6 sites. Western tubenose goby Proterorhinus semilunaris was found at 5 sites and Rainbow trout Oncorhynchus mykiss at 3 sites. Monkey goby Neogobius fluviatilis, Round goby Neogobius melanostomus and Eurasian carp Cyprinus carpio was recorded on 2 sites.

Keywords: non-native species, invasive species, fish species, invasive fish species, native fish species

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Authors: Moleseng Claude Moshobane

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Alien species cause considerable negative impacts on biodiversity, economy and public health. Impacts of alien species on public health have received a degree of attention worldwide, largely in developed countries, but scarce in developing countries. Here, we provide a review of human exposures and poisonings cases from native and alien plant species reported to poison information centers. A retrospective review of the Tygerberg Poison Information Centre (TPIC) and Poisons Information Centre (PIC) at Red Cross War Memorial Children's Hospital (RCWMCH) was conducted over approximately 2-year period (1 June 2015 through to 06 March 2017). Combined, TPIC and PIC handled 626 cases during the 2-year period. Toxicity cases were more abundant in Gauteng (47.1%), followed by Western Cape (29.4%). The primary mechanism of injury was ingestion (96.7%), and all cases were predominantly accidental. Most reported cases involved infants (20.6%), with few fully-grown adults related cases (5.8%). Adults presented minor to moderate toxicity, while infants none to minor toxicity. We conclude that reported toxicity cases on human health are biased towards few alien species and that several cases relate to unknown species of mushrooms. Public awareness is essential to reducing the poisoning incidences.

Keywords: alien species, poisoning, invasive species, public health

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Authors: Andrew Kanzunguze, Sopani Sichinga, Paston Simkoko, George Nxumayo, Cosmas, V. B. Dambo

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Early detection of plant invasions is a necessary prerequisite for effective invasive plant management in protected areas. This study was conducted to determine the distribution and abundance of alien invasive trees in Nyika National Park (NNP). Data on species' presence and abundance were collected from belt transects (n=31) in a 100 square kilometer area on the central plateau. The data were tested for normality using the Shapiro-Wilk test; Mann-Whitney test was carried out to compare frequencies and abundances between the species, and geographical information systems were used for spatial analyses. Results revealed that Black Wattle (Acacia mearnsii), Mexican Pine (Pinus patula) and Himalayan Raspberry (Rubus ellipticus) were the main alien invasive trees on the plateau. A. mearnsii was localized in the areas where it was first introduced, whereas P. patula and R. ellipticus were spread out beyond original points of introduction. R. ellipticus occurred as dense, extensive (up to 50 meters) thickets on the margins of forest patches and pine stands, whilst P. patula trees were frequent in the valleys, occurring most densely (up to 39 stems per 100 square meters) south-west of Chelinda camp on the central plateau with high variation in tree heights. Additionally, there were no significant differences in abundance between R. ellipticus (48) and P. patula (48) in the study area (p > 0.05) It was concluded that R. ellipticus and P. patula require more attention as compared to A. mearnsii. Howbeit, further studies into the invasion ecology of both P. patula and R. ellipticus on the Nyika plateau are highly recommended so as to assess the threat posed by the species on biodiversity, and recommend appropriate conservation measures in the national park.

Keywords: alien-invasive trees, Himalayan raspberry, Nyika National Park, Mexican pine

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Authors: Ji-Hyon Kil, Kew-Cheol Shim, Kyoung-Ae Park, Kyoungho Kim

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Ambrosia trifida L. is designated as invasive alien species by the Act on the Conservation and Use of Biodiversity by the Ministry of Environment, Korea. The purpose of present paper was to investigate the inhibitory effects of aqueous extracts of A.trifida on the development of root hairs of Triticum aestivum L., and Allium tuberosum Rottler ex Spreng and the electrophoretic protein patterns of their radicles. The development of root hairs was inhibited by increasing of aqueous extract concentrations. Through SDS-PAGE, the electrophoretic protein bands of extracted proteins from their radicles were appeared in controls, but protein bands of specific molecular weight disappeared or weakened in treatments. In conclusion, inhibitory effects of A. trifida made two receptor species changed morphologically, and at the molecular level in early growth stage.

Keywords: Ambrosia trifida L., invasive alien species, inhibitory effect, root hair, electrophoretic protein, radicle

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Authors: Stephen Osakue Amiandamhen, Schwaller Andreas, Martina Meincken, Luvuyo Tyhoda

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Invasive alien tree species are currently being cleared in South Africa as a result of the forest and water imbalances. These species grow wildly constituting about 40% of total forest area. They compete with the ecosystem for natural resources and are considered as ecosystem engineers by rapidly changing disturbance regimes. As such, they are harvested for commercial uses but much of it is wasted because of their form and structure. The waste is being sold to local communities as fuel wood. These species can be considered as potential feedstock for the production of phosphate bonded composites. The presence of bark in wood-based composites leads to undesirable properties, and debarking as an option can be cost implicative. This study investigates the potentials of these invasive species processed without debarking on some fundamental properties of wood-based panels. Some invasive alien tree species were collected from EC Biomass, Port Elizabeth, South Africa. They include Acacia mearnsii (Black wattle), A. longifolia (Long-leaved wattle), A. cyclops (Red-eyed wattle), A. saligna (Golden-wreath wattle) and Eucalyptus globulus (Blue gum). The logs were chipped as received. The chips were hammer-milled and screened through a 1 mm sieve. The wood particles were conditioned and the quantity of bark in the wood was determined. The binding matrix was prepared using a reactive magnesia, phosphoric acid and class S fly ash. The materials were mixed and poured into a metallic mould. The composite within the mould was compressed at room temperature at a pressure of 200 KPa. After initial setting which took about 5 minutes, the composite board was demoulded and air-cured for 72 h. The cured product was thereafter conditioned at 20°C and 70% relative humidity for 48 h. Test of physical and strength properties were conducted on the composite boards. The effect of binder formulation and fly ash content on the properties of the boards was studied using fitted response surface technology, according to a central composite experimental design (CCD) at a fixed wood loading of 75% (w/w) of total inorganic contents. The results showed that phosphate/magnesia ratio of 3:1 and fly ash content of 10% was required to obtain a product of good properties and sufficient strength for intended applications. The proposed products can be used for ceilings, partitioning and insulating wall panels.

Keywords: invasive alien tree species, phosphate bonded composites, physical properties, strength

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Authors: Champika S. Kariyawasam

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The distribution of gorse (Ulex europaeus) plants in South Australia has been modelled using 126 presence-only location data as a function of seven climate parameters. The predicted range of U. europaeus is mainly along the Mount Lofty Ranges in the Adelaide Hills and on Kangaroo Island. Annual precipitation and yearly average aridity index appeared to be the highest contributing variables to the final model formulation. The Jackknife procedure was employed to identify the contribution of different variables to gorse model outputs and response curves were used to predict changes with changing environmental variables. Based on this analysis, it was revealed that the combined effect of one or more variables could make a completely different impact to the original variables on their own to the model prediction. This work also demonstrates the need for a careful approach when selecting environmental variables for projecting correlative models to climatically distinct area. Maxent acts as a robust model when projecting the fitted species distribution model to another area with changing climatic conditions, whereas the generalized linear model, bioclim, and domain models to be less robust in this regard. These findings are important not only for predicting and managing invasive alien gorse in South Australia and Sri Lanka but also in other countries of the invasive range.

Keywords: invasive species, Maxent, species distribution modelling, Ulex europaeus

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Authors: Chetsada Noknoi

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This research aims to study the quality of life of alien workers in Thailand and to compare the quality of work life of alien workers based on personal factors and work factors. Data analysis is performed using frequencies, percentage, mean standard deviation, t-test and ANOVA. Findings will benefit to the relevant authorities to be aware of the quality of life of alien workers in Thailand. This will help to find ways to enhance the quality of life of alien workers. It also brings awareness to the problems and obstacles that alien workers face in their work and life. It is a strategic approach to improve the management of the country's alien workers to be more efficient and effective. Moreover, the knowledge can be the basis of service to the society in different ways.

Keywords: quality of work life, alien worker, contemporary marketing, management

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Authors: Cristine P. Canlas, Crislene Mae L. Gever, Patricia Bea R. Rosialda, Ma. Nina Regina M. Quibod, Perry Archival C. Buenavente, Normandy M. Barbecho, Cynthia Adeline A. Layusa, Michael Day

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Invasive plants have an impact on global biodiversity and ecosystem function, and their management is a complex and formidable task. Two of these invasive plant species, Lantana camara and Chromolaena odorata, are found in the Philippines. Lantana camara has the ability to suppress the growth of and outcompete neighboring plants. Chromolaena odorata causes serious agricultural and economical damage and causes fire hazards during dry season. In addition, both species has been reported to poison livestock. One of the known global management strategies to control invasive plants is the introduction of biological control agents. These natural enemies of the invasive plants reduce population density and impacts of the invasive plants, resulting in the balance of the nature in their invasion. Through secondary data sources, interviews, and field validation (e.g. microhabitat searches, sweep netting, opportunistic sampling, photo-documentation), we investigated whether the biocontrol agents previously released by the Philippine Coconut Authority (PCA) in their Davao Research Center to control these invasive plants are still present and are affecting their respective host weeds. We confirm the presence of the biocontrol agent of L. camara, Uroplata girardi, which was introduced in 1985, and Cecidochares connexa, a biocontrol agent of C. odorata released in 2003. Four other biocontrol agents were found to affect L. camara. Signs of damage (e.g. stem galls in C. odorata, and leaf mines in L. camara) signify that these biocontrol agents have successfully established outside of their release site in Davao. Further investigating the extent of the spread of these biocontrol agents in the Philippines and their damage to the two weeds will contribute to the management of invasive plant species in the country.

Keywords: invasive alien species, biological control agent, entomology, worst weeds

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Authors: Ning Li, Yaner Yan, Yajun Qiao, Shu-qing An

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Although seed dispersal is considered to be a key process determining the spatial structure and spread of invasive plant populations, few studies have explicitly addressed the link between dispersal vector behaviour, and seedling recruitment to gain insight into the process of exotic species invasion within a urban landscape. The present study tests the effects of native bird species on the dispersal and recruitment of invasive Phytolacca Americana in an urban garden. We found the invasive population of American pokeweed attracted both generalist species and specialist species to forage and disperse its seeds, with generalists Pycnonotus sinensis and Urocissa erythrorhyncha being by far the most important dispersers. Seedling numbers of P. Americana was strongly affected by perching behavior of bird dispersers. Moreover, two main disperser species, P. sinensis and U. erythrorhyncha govern a high quality dispersal service for P. Americana. Our results highlight the ability of invasive P. americana to recruit seed dispersal agents in urban habitats. However, if the newly recruited species could use the seedling safe site for perching shelter, the invasive plants will get a high regenerate rate in the invasive new habitats thus enhancing their invasive ability.

Keywords: frugivorous birds, phytolacca americana, seed dispersal, urban landscape

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Authors: Ella Zahra

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Sea urchins are keystone species in many global benthic ecosystems. The concentration of microplastics (MPs) in sea urchin organs was quantified in 120 individuals of 2 different species and from 4 sites across the Greek island Lipsi, with special interest in the differences between the native Arbacia lixula and the invasive Diadema setosum. Over 93% of MPs observed in both species were fibrous. MP abundance was found to correlate with exposure to open sea and harsh prevailing winds, irrespective of proximity to urban activities. The MP abundance in the invasive species was not found to be significantly dependent on site. Interestingly, the smaller native species contained significantly larger sized MPs than the invasive, possibly as a result of a greater feeding rate in A. lixula individuals. Sexually immature urchins may also have a higher feeding rate, giving rise to the negative correlation between gonad index and MPs per individual. The size of MPs ranged from 10µm to 24210µm, heavily skewed towards smaller particles. Few differences in colour were noted between the species and sites. MPs were detected in 100% of the samples with abundance ranging from 19.27 ± 6.77 to 26.83 ± 8.15 items per individual, or 3.55 ± 3.73 to 7.34 ± 10.51 items per gram of wet organ weight. This high value could lead to health risks in East Asia and the Mediterranean, where sea urchin is widely consumed, due to toxins adsorbed to the MPs.

Keywords: microplastics, plastic pollution, invertebrate ecology, invasive marine species

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Authors: Mutavhatsindi Tshinakaho

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Invasive alien plants (IAP’s) are referred to as species that are non-native to the ecosystem under consideration. Whose introduction causes or is likely to cause economic, ecological, or environmental harm. The integrated management of the invasive plant, Tithonia diversifolia, will be assessed through two herbicide trials (one on the seedlings and the other on matured plants) and a competitive trial between Tithonia and invasive grass species. The initial herbicide trial will be undertaken at the University of Venda Agricultural greenhouse facilities, where Tithonia will be planted in pot plants and watered every after two days until they reach at least 30 cm and will then be subjected to four different herbicide treatments (Metsulfuron methyl, Fluroxypyr, Picloram, Triclopyr), water will be utilised as a control. The percentage damage to foliar will be recorded. The second herbicide trial will be undertaken at Levubu road site, where matured Tithonia will be cut at at least 10cm above the ground and the subjected to herbicide treatments (Picloram, Fluroxypyr, Imazapyr, and Water as a control). The site will be visited post treatment for assessment. For the competition trial, tall grass species will be chosen as competitors (Panicum maximum and Eragrostis murvula), they will be grown at six densities per pot in the greenhouse facilities at the University of Venda, were they will be kept watered for the duration of the experiment. At the end of the experiment, plants will be removed from pots, and the above and below ground biomass will be weighed. The expected results are to know the effective integrated management strategy for T. diversifolia, the effective rehabilitation of T. diversifolia invaded habitats, and the effective chemical control of T. diversifolia

Keywords: foliar, biomass, competition, invasion

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Authors: Samiksha Raviraja, Junaid Arif

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One of the most important abilities in species is the ability to communicate. This paper proposes steps to take when and if aliens came in contact with humans, and how humans would communicate with them. The situation would be a time-sensitive scenario, meaning that communication is at the utmost importance if such an event were to happen. First, humans would need to establish mutual peace by conveying that there is no threat to the alien race. Second, the aliens would need to acknowledge this understanding and reciprocate. This would be extremely difficult to do regardless of their intelligence level unless they are very human-like and have similarities to our way of communicating. The first step towards understanding their mind is to analyze their level of intelligence - Level 1-Low intelligence, Level 2-Human-like intelligence or Level 3-Advanced or High Intelligence. These three levels go hand in hand with the Kardashev scale. Further, the Barrow scale will also be used to categorize alien species in hopes of developing a common universal language to communicate in. This paper will delve into how the level of intelligence can be used toward achieving communication with aliens by predicting various possible scenarios and outcomes by proposing an intensive categorization system. This can be achieved by studying their Emotional and Intelligence Quotient (along with technological and scientific knowledge/intelligence). The limitations and capabilities of their intelligence must also be studied. By observing how they respond and react (expressions and senses) to different kinds of scenarios, items and people, the data will help enable good categorisation. It can be hypothesised that the more human-like aliens are or can relate to humans, the more likely it is that communication is possible. Depending on the situation, either human can teach aliens a human language, or humans can learn an alien language, or both races work together to develop a mutual understanding or mode of communication. There are three possible ways of contact. Aliens visit Earth, or humans discover aliens while on space exploration or through technology in the form of signals. A much rarer case would be humans and aliens running into each other during a space expedition of their own. The first two possibilities allow a more in-depth analysis of the alien life and enhanced results compared. The importance of finding a method of talking with aliens is important in order to not only protect Earth and humans but rather for the advancement of Science through the shared knowledge between the two species.

Keywords: intelligence, Kardashev scale, Barrow scale, alien civilizations, emotional and intelligence quotient

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Authors: Suganiya Rama Rao, Yoon-Yen Yow, Thor-Seng Liew, Shyamala Ratnayeke

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Invasive snails in the genus Pomacea have spread across Southeast Asia including Peninsular Malaysia. Apart from significant economic costs to wetland crops, very little is known about the snails’ effects on native species, and wetland function through their alteration of macrophyte communities. This study was conducted to establish diagnostic characteristics of Pomacea species in the Malaysian environment using genetic and morphological criteria. Snails were collected from eight localities in northern and central regions of Peninsular Malaysia. The mitochondrial COI gene of 52 adult snails was amplified and sequenced. Maximum likelihood analysis was used to analyse species identity and assess phylogenetic relationships among snails from different geographic locations. Shells of the two species were compared using geometric morphometric analysis and covariance analyses. Shell height accounted for most of the observed variation between P. canaliculata and P. maculata, with the latter possessing a smaller mean ratio of shell height: aperture height (p < 0.0001) and shell height to shell width (give p < 0.0001). Genomic and phylogenetic analysis demonstrated the presence of two monophyletic taxa, P. canaliculata and P. maculata, in Peninsular Malaysia samples. P. maculata co-occurred with P. canaliculata in 5 localities, but samples from 3 localities contained only P. canaliculata. This study is the first to confirm the presence of two of the most invasive species of Pomacea in Peninsular Malaysia using a genomic approach. P. canaliculata appears to be the more widespread species. Despite statistical differences, both quantitative and qualitative morphological characteristics demonstrate much interspecific overlap and intraspecific variability; thus morphology alone cannot reliably verify species identity. Molecular techniques for distinguishing between these two highly invasive Pomacea species are needed to understand their specific ecological niches and develop effective protocols for their management.

Keywords: Pomacea canaliculata, Pomacea maculata, invasive species, phylog enetic analysis, geometric morphometric analysis

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Authors: Patrick M. Garvey, Roger P. Pech, Daniel M. Tompkins

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Competition is a widespread interaction and natural selection will encourage the development of mechanisms that recognise and respond to dominant competitors, if this information reduces the risk of a confrontation. As olfaction is the primary sense for most mammals, our research tested whether olfactory ‘eavesdropping’ mediates alien species interactions and whether we could exploit our understanding of this behaviour to create ‘super-lures’. We used a combination of pen and field experiments to evaluate the importance of this behaviour. In pen trials, stoats (Mustela erminea) were exposed to the body odour of three dominant predators (cat / ferret / African wild dog) and these scents were found to be attractive. A subsequent field trial tested whether attraction displayed towards predator odour, particularly ferret (Mustela furo) pheromones, could be replicated with invasive predators in the wild. We found that ferret odour significantly improved detection and activity of stoats and hedgehogs (Erinaceus europaeus), while also improving detections of ship rats (Rattus rattus). Our current research aims to identify the key components of ferret odour, using chemical analysis and behavioural experiments, so that we can produce ‘scent from a can’. A lure based on a competitors’ odour would be beneficial in many circumstances including: (i) where individuals display variability in attraction to food lures, (ii) there are plentiful food resources available, (iii) new immigrants arrive into an area, (iv) long-life lures are required. Pest management can therefore benefit by exploiting behavioural responses to odours to achieve conservation goals.

Keywords: predator interactions, invasive species, eavesdropping, semiochemicals

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Authors: M. L. Gaol, I. W. Mudita

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Indonesia is well known as a country covered by lush tropical rain forests, but in fact, the northeastern part of the country, within the areas geologically known as Lesser Sunda, the dominant vegetation is tropical savanna. Lesser Sunda is a chain of islands located closer to Australia than to islands in the other parts of the country. Among those of islands in the chain which is closes to Australia, and thereby most strongly affected by the hot and dry Australian climate, is the island of Timor, the western part of which belongs to Indonesia and the eastern part is a sovereign state East Timor. Regardless of being the most dominant vegetation cover, tropical savanna in West Timor, especially its understory, is rarely investigated. This research was therefore carried out to investigate the structure, composition and diversity of the understory of this tropical savanna as the basis for looking at the possibility of introducing other spesieis for various purposes. For this research, 14 terrestrial communities representing major types of the existing savannas in West Timor was selected with aid of the most recently available satellite imagery. At each community, one stand of the size of 50 m x 50 m most likely representing the community was as the site of observation for the type of savanna under investigation. At each of the 14 communities, 20 plots of 1 m x 1 m in size was placed at random to identify understory species and to count the total number of individuals and to estimate the cover of each species. Based on such counts and estimation, the important value of each species was later calculated. The results of this research indicated that the understory of savanna in West Timor consisted of 73 understory species. Of this number of species, 18 species are grasses and 55 are non-grasses. Although lower than non-grass species, grass species indeed dominated the savanna as indicated by their number of individuals (65.33 vs 34.67%), species cover (57.80 vs 42.20%), and important value (123.15 vs 76.85). Of the 14 communities, the lowest density of grass was 13.50/m2 and the highest was 417.50/m2. Of 18 grass species found, all were commonly found as agricultural weeds, whereas of 55 non-grass, 10 species were commonly found as agricultural weeds, environmental weeds, or invasive species. In terms of better managing the savanna in the region, these findings provided the basis for planning a more integrated approach in managing such agricultural and environmental weeds as well as invasive species by considering the structure, composition, and species diversity of the understory species existing in each site. These findings also provided the basis for better understanding the flora of the region as a whole and for developing a flora database of West Timor in future.

Keywords: tropical savanna, understory species, integrated management, weedy and invasive species

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Authors: Rifilwe Victor Modiba, Stefan Hendric Foord

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Alien invasive plants (IAP’s) have considerable negative impacts on freshwater habitats and South Africa has implemented an innovative Work for Water (WfW) programme for the systematic removal of these plants aimed at, amongst other objectives, restoring biodiversity and ecosystem services in these threatened habitats. These restoration processes are expensive and have to be evidence-based. In this study in-stream macroinvertebrate and adult Odonata assemblages were used as indicators of restoration success by quantifying the response of biodiversity metrics for these two groups to the removal of IAP’s in a strategic water resource of South Africa that is extensively invaded by invasive alien plants (IAP’s). The study consisted of a replicated design that included 45 sampling units, viz. 15 invaded, 15 uninvaded and 15 cleared sites stratified across the upper reaches of six sub-catchments of the Luvuvhu river catchment, Limpopo Province. Cleared sites were only considered if they received at least two WfW treatments in the last 3 years. The Benthic macroinvertebrate and adult Odonate assemblages in each of these sampling were surveyed from between November and March, 2013/2014 and 2014/2015 respectively. Generalized Linear Models (GLM) with a log link function and Poisson error distribution were done for metrics (invaded, cleared, and uninvaded) whose residuals were not normally distributed or had unequal variance and for abundance. RDA was done for EPTO genera (Ephemeroptera, Plecoptera, Trichoptera and Odonata) and adult Odonata species abundance. GLM was done to for the abundance of Genera and Odonates that had the association with the RDA environmental factors. Sixty four benthic macroinvertebrate families, 57 EPTO genera, and 45 adult Odonata species were recorded across all 45 sampling units. There was no significant difference between the SASS5 total score, ASPT, and family richness of the three invasion classes. Although clearing only had a weak positive effect on the adult Odonate species richness it had a positive impact on DBI scores. These differences were mainly the result of significantly larger DBI scores in the cleared sites as compared to the invaded sites. Results suggest that water quality is positively impacted by repeated clearing pointing to the importance of follow up procedures after initial clearing. Adult Odonate diversity as measured by richness, endemicity, threat and distribution respond positively to all forms of the clearing. The clearing had a significant impact on Odonate assemblage structure but did not affect EPTO structure. Variation partitioning showed that 21.8% of the variation in EPTO assemblage can be explained by spatial and environmental variables, 16% of the variation in Odonate structure was explained by spatial and environmental variables. The response of the diversity metrics to clearing increased in significance at finer taxonomic resolutions, particularly of adult Odonates whose metrics significantly improved with clearing and whose structure responded to both invasion and clearing. The study recommends the use of DBI for surveying river health when hydraulic biotopes are poor.

Keywords: DBI, evidence-based conservation, EPTO, macroinvetebrates

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Authors: Kishor Prasad Bhatta, Suman Ghimire, Durga Prasad Joshi

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Invasive Alien Species (IAS) are considered waste forest resources in Nepal. The rapid expansion of IAS is one of the nine main drivers of forest degradation, though the extent and distribution of this species are not well known. Further, the knowledge of the impact of IAS removal on forest plant diversity is hardly known, and the possibilities of income generation from them at the grass-root communities are rarely documented. Systematic sampling of 1% with nested circular plots of 500 square meters was performed in IAS removed and non-removed area, each of 30 hectares in Udayapur Community Forest User Group (CFUG), Chitwan, central Nepal to observe whether the removal of IAS contributed to an increase in plant diversity. In addition, ten entrepreneurs of Udaypur CFUG, involved in the charcoal production, briquette making and marketing were interviewed and interacted as well as their record keeping booklets were reviewed to understand if the charcoal production contributed to their income and employment. The average annual precipitation and temperature of the study area is 2100 mm and 34 degree Celsius respectively with Shorea robusta as main tree species and Eupatorium odoratum as dominant IAS. All the interviewed households were from the ̔below-poverty-line’ category as per Community Forestry Guidelines. A higher Shannon-Weiner plant diversity index at regeneration level was observed in IAS removed areas (2.43) than in control site (1.95). Furthermore, the number of tree seedlings and saplings in the IAS harvested blocks were significantly higher (p < 0.005) compared to the unharvested one. The sale of charcoal produced through the pyrolysis of IAS in ̔ Bio-energy kilns’ contributed for an average increased income of 30.95 % (Nepalese rupees 31,000) of the involved households. Despite above factors, some operational policy hurdles related to charcoal transport and taxation existed at field level. This study suggests that plant diversity could be increased through the removal of IAS, and considerable economic benefits could be achieved if charcoal is substantially produced and utilized.

Keywords: briquette, economic benefits, pyrolysis, regeneration

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Authors: Yanmei Xiong, Baowen Liao, Kun Xin, Zhongmao Jiang, Hao Guo, Yujun Chen, Mei Li

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Conversion of mangroves to aquaculture ponds represented as one major reason for mangrove loss in Asian countries in the 20th century. Recently the Chinese government has set a goal to increase 48,650 ha (more than the current mangrove area) of mangroves before the year of 2025 and “rehabilitation of aquaculture ponds to mangroves” projects are considered to be the major pathway to increase the mangrove area of China. It remains unclear whether natural colonization is feasible and what are the main influencing factors for mangrove restoration in these projects. In this study, a total of 17 rehabilitation sites in Dongzhai Bay, Hainan, China were surveyed for vegetation, soil and surface elevation five years after the rehabilitation project was initiated. Colonization of non-planted mangrove species was found at all sites and non-planted species dominated over planted species at 14 sites. Mangrove plants could only be found within the elevation range of -20 cm to 65 cm relative to the mean sea level. Soil carbon and nitrogen contents of the top 20 cm were generally low, ranging between 0.2%–1.4% and 0.03%–0.09%, respectively, and at each site, soil carbon and nitrogen were significantly lower at elevations with mangrove plants than lower elevations without mangrove plants. Seven sites located at the upper stream of river estuaries, where soil salinity was relatively lower, and nutrient was relatively higher, was dominated by non-planted Sonneratia caseolaris. Seven sites located at the down-stream of river estuaries or in the inner part of the bay, where soil salinity and nutrient were intermediate, were dominated by non-planted alien Sonneratia apetala. Another three sites located at the outer part of the bay, where soil salinity was higher and nutrient was lower, were dominated by planted species (Rhizophora stylosa, Kandelia obovata, Aegiceras corniculatum and Bruguiera sexangula) with non-planted S. apetala and Avicennia marina also found. The results suggest that natural colonization of mangroves is feasible in pond rehabilitation projects given the rehabilitation of tidal activities and appropriate elevations. Surface elevation is the major determinate for the success of mangrove rehabilitation, and soil salinity and nutrients are important in shaping vegetation structure. The colonization and dominance of alien species (Sonneratia apetala in this case) in some rehabilitation sites poses invasion risks and thus cautions should be taken when introducing alien mangrove species.

Keywords: coastal wetlands, ecological restoration, mangroves, natural colonization, shrimp pond rehabilitation, wetland restoration

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Authors: Thabiso Michael Mokotjomela, Jasper Knight

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Intensification of agricultural food production in sub-Saharan Africa is of paramount importance as a means of increasing the food security of communities that are already experiencing a range of environmental and socio-economic stresses. However, achieving this aim faces several challenges including ongoing climate change, increased resistance of diseases and pests, extreme environmental degradation partly due to biological invasions, land tenure and management practices, socio-economic developments of rural populations, and national population growth. In particular, non-native plant species tend to display greater adaptation capacity to environmental stress than native species that form important food resource base for human beings, thus suggesting a potential for usage to shift accordingly. Based on review of the historical benefits of non-native plant species in food production in sub-Saharan Africa, we propose that use of non-invasive, non-native plant species and/or the genetic modification of native species might be viable options for future agricultural sustainability in this region. Coupled with strategic foresight planning (e.g. use of biological control agents that suppress plant species’ invasions), the consumptive use of already-introduced non-native species might help in containment and control of possible negative environmental impacts of non-native species on native species, ecosystems and biodiversity, and soil fertility and hydrology. Use of non-native species in food production should be accompanied by low cost agroecology practices (e.g. conservation agriculture and agrobiodiversity) that may promote the gradual recovery of natural capital, ecosystem services, and promote conservation of the natural environment as well as enhance food security.

Keywords: food security, invasive species, agroecology, agrobiodiversity, socio-economic stresses

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Authors: Leanda Denise Mason, Philip William Bateman, Grant Wardell-Johnson

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Ecological traps attract biota to low-quality habitats. Landscape traps are zones caught in a vortex of spiraling degradation. Here, we demonstrate how short-range endemic traits may make such taxa vulnerable to ecological and landscape traps. Three short-range endemic mygalomorph spider species were used in this study. Mygalomorphs can be long-lived ( > 40 years) and select sites for permanent burrows in their early dispersal phase. Spiderlings from two species demonstrated choice for microhabitats that correspond to where adults typically occur. An invasive veldt grass microhabitat was selected almost exclusively by spiderlings of the third species. Habitat dominated by veldt grass has lower prey diversity and abundance than undisturbed habitats and therefore acts as an ecological trap for this species. Furthermore, as a homogenising force, veldt grass can spread to form a landscape trap in naturally heterogeneous ecosystems. Selection of specialised microhabitats of short-range endemics may explain high extinction rates in old, stable landscapes undergoing (human-induced) rapid change.

Keywords: biotic homogenization, invasive species, mygalomorph, short-range endemic

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Authors: Yuchen LI, Martyn Kurr, Peter Golyshin

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Biological invasion is a global problem. Invasive species can threaten local ecosystems by competing for resources, consuming local species, and reproducing faster than natives. Sargassum muticum is an invasive algae in the UK. It negatively impacts local algae through overshading and can cause reductions in local biodiversity. One possibility for its success is herbivore release. According to the Enemy Release Hypothesis, invasives are less impacted by local herbivores than natives. In many species, gastrointestinal (GI) tract microbes have been found as a key factor in food preference and similar mechanisms may exist in the relationship between local consumers and S. muticum. Some populations of native Littorina snails accept S. muticum as a food source, while others avoid it. This project aims to establish the relationship between GI tract microbes and the feeding preferences of L. littorea, when offered both native algae and S. muticum. Individuals of L. littorea from a site invaded by S. muticum around 18 years ago were compared to those from an un-invaded site nearby. Sargassum-experienced snails are more likely to consume it than those naïve, and pronounced differences were found in the GI-tract microbial communities through 16S (prokaryote) and 18S (eukaryote) sequencing. Sargassum-naïve snails were then exposed to a faecal pellets from experienced snails to ‘inoculate’ them with microbes from the exposed snails. Preliminary results suggest these faecal-pellet-exposed but otherwise Sargassum-naïve snails subsequently begun consuming S. muticum. It is unclear if these results are due to genuine changes in GI-tract microbes or through some other mechanism, such as behavioural responses to chemical cues in the faecal pellets, but these results are nevertheless of significance for invasive ecology, suggesting that foraging preferences for an invasive prey type are malleable and possibly programmable in laboratory settings.

Keywords: invasive algae, sea snails, gut microbiome, biocontrol

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Authors: Atef Mohamed Kamel Ahmed

Abstract:

House crows (Corvus splendens) have become well-established in Ismailia Governorate, Egypt, where they pose several and serious impacts on native biodiversity, ecosystems and humans health. However, there is a lack of literature on the status and effects of invasive birds in Egypt. Over the past 10 years in Ismailia, House crow have increased at a rate approaching (60000 birds)15% per annum; if this were allowed to continue, the population now 10909 birds and will exceed more by 2013, probably accompanied by an increase in geographical distribution in all Suez canal regions and an exacerbation of the problems caused. Population control is recommended, involving improvements in urban hygiene and the capture of adult crows using stupefying baits. Suitable baits and stupefacient doses were identified and these should be used annually, just before the breeding season. Control should be accompanied by studies of relevant aspects of the biology of house crows in Ismailia Governorate.

Keywords: environmental impact t, non-native invasive species, House crow birds, risk management, Ismailia-Egypt

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Authors: Samia Elfekih, Wee Tek Tay, Karl Gordon, Paul De Barro

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Invasive species represent an increasing threat to food biosecurity, causing significant economic losses in agricultural systems. An example is the sweet potato whitefly, Bemisia tabaci, which is a complex of morphologically indistinguishable species causing average annual global damage estimated at US$2.4 billion. The Bemisia complex represents an interesting model for evolutionary studies because of their extensive distribution and potential for invasiveness and population expansion. Within this complex, two species, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) have invaded well beyond their home ranges whereas others, such as Indian Ocean (IO) and Australia (AUS), have not. In order to understand why some Bemisia species have become invasive, genome-wide sequence scans were used to estimate population dynamics over time and relate these to climate. The Bayesian Skyline Plot (BSP) method as implemented in BEAST was used to infer the historical effective population size. In order to overcome sampling bias, the populations were combined based on geographical origin. The datasets used for this particular analysis are genome-wide SNPs (single nucleotide polymorphisms) called separately in each of the following groups: Sub-Saharan Africa (Burkina Faso), Europe (Spain, France, Greece and Croatia), USA (Arizona), Mediterranean-Middle East (Israel, Italy), Middle East-Central Asia (Turkmenistan, Iran) and Reunion Island. The non-invasive ‘AUS’ species endemic to Australia was used as an outgroup. The main findings of this study show that the BSP for the Sub-Saharan African MED population is different from that observed in MED populations from the Mediterranean Basin, suggesting evolution under a different set of environmental conditions. For MED, the effective size of the African (Burkina Faso) population showed a rapid expansion ≈250,000-310,000 years ago (YA), preceded by a period of slower growth. The European MED populations (i.e., Spain, France, Croatia, and Greece) showed a single burst of expansion at ≈160,000-200,000 YA. The MEAM1 populations from Israel and Italy and the ones from Iran and Turkmenistan are similar as they both show the earlier expansion at ≈250,000-300,000 YA. The single IO population lacked the latter expansion but had the earlier one. This pattern is shared with the Sub-Saharan African (Burkina Faso) MED, suggesting IO also faced a similar history of environmental change, which seems plausible given their relatively close geographical distributions. In conclusion, populations within the invasive species MED and MEAM1 exhibited signatures of population expansion lacking in non-invasive species (IO and AUS) during the Pleistocene, a geological epoch marked by repeated climatic oscillations with cycles of glacial and interglacial periods. These expansions strongly suggested the potential of some Bemisia species’ genomes to affect their adaptability and invasiveness.

Keywords: whitefly, RADseq, invasive species, SNP, climate change

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Authors: Thomas Schalow

Abstract:

This paper posits the need to take a cross-cultural approach to communication with non-human cultures and intelligences in order to meet the following three imminent contingencies: communicating with sentient biological intelligences, communicating with extraterrestrial intelligences, and communicating with artificial super-intelligences. The paper begins with a discussion of how intelligence emerges. It disputes some common assumptions we maintain about consciousness, intention, and language. The paper next explores cross-cultural communication among humans, including non-sapiens species. The next argument made is that we need to become much more serious about communicating with the non-human, intelligent life forms that already exist around us here on Earth. There is an urgent need to broaden our definition of communication and reach out to the other sentient life forms that inhabit our world. The paper next examines the science and philosophy behind CETI (communication with extraterrestrial intelligences) and how it has proven useful, even in the absence of contact with alien life. However, CETI’s assumptions and methodology need to be revised and based on the cross-cultural approach to communication proposed in this paper if we are truly serious about finding and communicating with life beyond Earth. The final theme explored in this paper is communication with non-biological super-intelligences using a cross-cultural communication approach. This will present a serious challenge for humanity, as we have never been truly compelled to converse with other species, and our failure to seriously consider such intercourse has left us largely unprepared to deal with communication in a future that will be mediated and controlled by computer algorithms. Fortunately, our experience dealing with other human cultures can provide us with a framework for this communication. The basic assumptions behind intercultural communication can be applied to the many types of communication envisioned in this paper if we are willing to recognize that we are in fact dealing with other cultures when we interact with other species, alien life, and artificial super-intelligence. The ideas considered in this paper will require a new mindset for humanity, but a new disposition will prepare us to face the challenges posed by a future dominated by artificial intelligence.

Keywords: artificial intelligence, CETI, communication, culture, language

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Authors: Samir Chekchaki, ArifaBeddiar

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Nowadays, more and more species are introduced outside their natural range. If most of them remain difficult, some may adopt a much more dynamic behavior. Indeed, we have witnessed in recent decades, the development of high forests of Acacia mearnsii in El Kala National Park. Introduced indefinitely, this leguminous intended to make money (nitrogen supply for industrial plantations of Eucalyptus), became one of the most invasive and more costly in terms of forest management. It has crossed all barriers: it has acclimatized, naturalized and then expanded through diverse landscapes; entry into competition with native species such as cork oak and altered ecosystem functioning. Therefore, it is interesting to analyze this new threat by relying on plants as bio-indicator for assessing biodiversity at different scales. We have identified the species present in several plots distributed in a range of vegetation types subjected to different degrees of disturbance by using the braun-blanquet method. Fifty-six species have been recorded. They are distributed in 48 genera and 29 families. The analysis of the relative frequency of species correlated with relative abundance clearly shows that the Acacia mearnsii feels marginalized. The ecological analysis of this biological invasion shows that disruption of either natural or anthropogenic origin (fire, prolonged drought, cut) represent the factors that exacerbate invasion by opening invasion windows. The lifting of seeds of Acacia mearnsii lasting physical dormancy (and variable) is ensured by the thermal shock in relation to its heliophilous character.

Keywords: Acacia mearnsii De Wild, El Kala National park, fire, invasive, vegetation

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Authors: Sangho Park, Mansoo Kim, Kyujung Chae, Junhyuk Yang

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The International Maritime Organization (IMO) recognized the problem of invasive species invasion and adopted the "International Convention for the Control and Management of Ships' Ballast Water and Sediments" in 2004, which came into force on September 8, 2017. In 2011, the IMO approved the "Guidelines for the Control and Management of Ships' Biofouling to Minimize the Transfer of Invasive Aquatic Species" to minimize the movement of invasive species by hull-attached organisms and required ships to manage the organisms attached to their hulls. Invasive species enter new environments through ships' ballast water and hull attachment. However, several obstacles to implementing these guidelines have been identified, including a lack of underwater cleaning equipment, regulations on underwater cleaning activities in ports, and difficulty accessing crevices in underwater areas. The shipping industry, which is the party responsible for understanding these guidelines, wants to implement them for fuel cost savings resulting from the removal of organisms attached to the hull, but they anticipate significant difficulties in implementing the guidelines due to the obstacles mentioned above. Robots or people remove the organisms attached to the hull underwater, and the resulting wastewater includes various species of organisms and particles of paint and other pollutants. Currently, there is no technology available to sterilize the organisms in the wastewater or stabilize the heavy metals in the paint particles. In this study, we aim to analyze the characteristics of the wastewater generated from the removal of hull-attached organisms and select the optimal treatment technology. The organisms in the wastewater generated from the removal of the attached organisms meet the biological treatment standard (D-2) using the sterilization technology applied in the ships' ballast water treatment system. The heavy metals and other pollutants in the paint particles generated during removal are treated using stabilization technologies such as thermal decomposition. The wastewater generated is treated using a two-step process: 1) development of sterilization technology through pretreatment filtration equipment and electrolytic sterilization treatment and 2) development of technology for removing particle pollutants such as heavy metals and dissolved inorganic substances. Through this study, we will develop a biological removal technology and an environmentally friendly processing system for the waste generated after removal that meets the requirements of the government and the shipping industry and lays the groundwork for future treatment standards.

Keywords: biofouling, ballast water treatment system, filtration, sterilization, wastewater

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Authors: V. W. Kamgang, A. Van Der Goot, N. C. Bennett, A. Ganswindt

Abstract:

The roan antelope (Hippotragus equinus) is the second largest antelope species in Africa. These past decades, populations of roan antelope are declining drastically throughout Africa. This situation resulted in the development of intensive breeding programmes for this species in Southern African, where they are popular game ranching herbivores in with increasing numbers in captivity. Nowadays, avoidance of stress is important when managing wildlife to ensure animal welfare. In this regard, a non-invasive approach to monitor the adrenocortical function as a measure of stress would be preferable, since animals are not disturbed during sample collection. However, to date, a non-invasive method has not been established for the roan antelope. In this study, we validated a non-invasive technique to monitor the adrenocortical function in this species. Herein, we performed an adrenocorticotropic hormone (ACTH) stimulation test at Lapalala reserve Wilderness, South Africa, using adult captive roan antelopes to determine the stress-related physiological responses. Two individually housed roan antelope (a male and a female) received an intramuscular injection with Synacthen depot (Norvatis) loaded into a 3ml syringe (Pneu-Dart) at an estimated dose of 1 IU/kg. A total number of 86 faecal samples (male: 46, female: 40) were collected 5 days before and 3 days post-injection. All samples were then lyophilised, pulverized and extracted with 80% ethanol (0,1g/3ml) and the resulting faecal extracts were analysed for immunoreactive faecal glucocorticoid metabolite (fGCM) concentrations using five enzyme immunoassays (EIAs); (i) 11-oxoaetiocholanolone I (detecting 11,17 dioxoandrostanes), (ii) 11-oxoaetiocholanolone II (detecting fGCM with a 5α-pregnane-3α-ol-11one structure), (iii) a 5α-pregnane-3β-11β,21-triol-20-one (measuring 3β,11β-diol CM), (iv) a cortisol and (v) a corticosterone. In both animals, all EIAs detected an increase in fGCM concentration 100% post-ACTH administration. However, the 11-oxoaetiocholanolone I EIA performed best, with a 20-fold increase in the male (baseline: 0.384 µg/g, DW; peak: 8,585 µg/g DW) and a 17-fold in the female (baseline: 0.323 µg/g DW, peak: 7,276 µg/g DW), measured 17 hours and 12 hours post-administration respectively. These results are important as the ability to assess adrenocortical function non-invasively in roan can now be used as an essential prerequisite to evaluate the effects of stressful circumstances; such as variation of environmental conditions or reproduction in other to improve management strategies for the conservation of this iconic antelope species.

Keywords: adrenocorticotropic hormone challenge, adrenocortical function, captive breeding, non-invasive method, roan antelope

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Authors: Thomas Schalow

Abstract:

It is commonly recognized that our present curriculum is not preparing students to function in the 21st century. This is particularly true in regard to communication needs across cultures - both human and non-human. In this paper, a comprehensive theory of communication-based on communication with non-human cultures and intelligences is presented to meet the following three imminent contingencies: communicating with sentient biological intelligences, communicating with extraterrestrial intelligences, and communicating with artificial super-intelligences. The paper begins with the argument that we need to become much more serious about communicating with the non-human, intelligent life forms that already exists around us here on Earth. We need to broaden our definition of communication and reach out to other sentient life forms in order to provide humanity with a better perspective of its place within our ecosystem. The paper next examines the science and philosophy behind CETI (communication with extraterrestrial intelligences) and how it could prove useful even in the absence of contact with alien life. However, CETI’s assumptions and methodology need to be revised in accordance with the communication theory being proposed in this paper if we are truly serious about finding and communicating with life beyond Earth. The final theme explored in this paper is communication with non-biological super-intelligences. Humanity has never been truly compelled to converse with other species, and our failure to seriously consider such intercourse has left us largely unprepared to deal with communication in a future that will be mediated and controlled by computer algorithms. Fortunately, our experience dealing with other cultures can provide us with a framework for this communication. The basic concepts behind intercultural communication can be applied to the three types of communication envisioned in this paper if we are willing to recognize that we are in fact dealing with other cultures when we interact with other species, alien life, and artificial super-intelligence. The ideas considered in this paper will require a new mindset for humanity, but a new disposition will yield substantial gains. A curriculum that is truly ready for the 21st century needs to be aligned with this new theory of communication.

Keywords: artificial intelligence, CETI, communication, language

Procedia PDF Downloads 325

Authors: M. N. Alo, U. C. C. Egbule, J. O. Orji, C. J. Aneke

Abstract:

Microbiological analysis of soil from Onu-Ebonyi Izzi local government area of Ebonyi State, Nigeria contaminated with inorganic fertilizer was carried out with a view to determine the effect of the fertilizer on the microbial flora of the soil. soil samples were analyzed for microbial burden. the result showed that the following organisms were isolated with their frequency of their occurrence as follows:pseudomonas species (33.3%) and aspergillus species (54.4%) had the highest frequncy of occurence in the whole sample of batches, while streptococcus species had 6.0% and Geotrichum species (5.3%) had the least and other predominant microorganism isolated: bacillus species,staphylococcus species and vibrio species, Escherichia species, rhzizopus species, mucor species and fusaruim species. From the result, it could be concluded that the soil was contaminated and this could affect adversely the fertility of the soil .

Keywords: soil, bacteria, fungi, inorganic fertilizer, Onu- Ebonyi

Procedia PDF Downloads 471