Wednesday, June 5, 2019
Biodiversity Impact Of Invasive Plants In Tropical Biodiversity Biology Essay
Biodiversity Impact Of Invasive Plants In equatorialal Biodiversity Biology Essay equatorialal zone is the biodiversity hot spot (Briggs, 1996) about three-quarters of the worlds species be curb to the tropic of the world (Wilson, 1992). Though tropic timberland ecosystems ar more resistant to invasion by alien lay outs than other biome (Edward, 2009), they are exceedingly wakeless by invasive species (Association for Tropical Biology and Conservation, biotropica, 2010). Invasive species are creating significant challenges to the management and conservation of the indigenous biodiversity. The distribution of invasive nominate species occurred at ecosystem take, association take and at the species level (Meyer et al., 2004). At least one exotic species is present in almost all tropical areas (Usher 1991).Invasive nominates alter the local anesthetic environment more favourable to them but less favourable to the infixed species (Hoffmann et al., 2004) and thus modified lo cal ecosystem. Biological invasion has become a coarse economic, social, and particularly ecological problem of global impact (Cavalcante and Major, 2006). The important ecological impacts identified include reduction in native plant species richness, abundance and alternation in ecological function (Vitousek Walker, 1989 Adair Groves, 1998 Levine et al., 2003 Ogle, Reiners Gerow, 2003 Vila et al., 2006 Hejda, Pysek Jarosik, 2009 cited in Martin and Murray, 2010). Invasive plant species can covert the large area tropical vegetation to an exotic monoculture and greatly subdue the biodiversity, for example, the number of birds, mammals, tree seedlings were greatly reduced in Australia after(prenominal) the invasion of the area by alien plant species (Braithwaite et al. 1989) and Cogongrass (Imperata cylindrica) forms large, mo nonypic expanses, with Asia reporting over 35 million acres affected (Garrity et al. 1997).Invasive species are posing a serious threat to biodiversity ( IUCN, 2000). The Millennium Ecosystem Assessment (2005) has pointed that the impacts of invasive species on the tropical ecosystems are increasing rapidly. Similarly, recognizing the increasing issue of impact of invasive species, Convention on Biological Diversity, call on contracting parties to prevent the introduction of, control or eradicate invasive species that threaten ecosystems, habitats and species Article 8 (h).This systematic recapitulation attempt to summarises, appraise and communicate the resultsof the available studies to address the impact of invasive plants on tropical biodiversity. This protocol volition provide a priori guide and allow scientific communities to comment on methodology and other relevant issues. Diverse studies are available related to impact of invasive plant species on tropical biodiversity. Some studies suggest that invasion of native vegetation by the non native plants does not always lead to decline in native biodiversity (e.g. Sax Gaines, 2003 Sax, Kinlan Smith, 2005). Biological invasions have been the subject of intensive ecological research during the last two decades (Fine 2001). world-wide studied have been done for many tropical forests e.g. the Hawaiian Islands (Fine, 2002) but some authors argues that the biological invasion research has generally ignored tropical forests ( Drake et al. 1989, Groves Burdon 1986, Williamson 1996 cited in Fine, 2002).In such contentious situation, it seems quite reasonable to syntheses these studies to improve the efficiency of the conservation efforts in preserving biodiversity of the tropics and develop a concrete evidence anchor on the impact of invasive species which will provide unbiased scientific evidence base to help decision-makers to decide and implement necessary policy interjection to stop further invasion of the tropical biodiversity and identify areas where evidence is lacking to pick out research and funding on more crucial agendas.Objective of the reviewPr imary doubtWhat are the effects of invasive plants on biodiversity of the tropical zone?Table 1 Definition of components of the primary systematic review questionSubject hitchComparatorOutcomesBiodiversityin the tropical zoneInvasion by invasive plant species in tropical zoneBiodiversity in forest, savannas or grassland in the beginning the invasion or any relevant or any relevantAny reported change in tropical biodiversity e.g.Species richness, abundance of native plant species, tree densityMethods3.1. Search StrategyRelevant published and unpublished literature and selective training will be collated by following strategy. Due to the preference constraints only English language literatures will be taken into consideration.3.1.1 Scope of searchI will use the following database search to retrieve the literatures and dataISI Web of Knowledge wisdom DirectWiley InterScienceCambridge JournalCab DirectCSA Biological Sciences developmentbase (CSA/CIG)BIOTROPICAIn addition to grizz ly literatures are searched in the website of relevant presidential term as listed in section 3.1.5 which helps to reveal important information about the tropical forestry and invasive species interaction. First searches are conducted on title, keyword and abstract basis and followed by full text searches. Hits are then checked for the relevance.3.1.2 Search termsEffective and comprehensive list of related key words as exposit in the table -2 will be used to retrieve the literatures from the database specified above.Table 2 Search terms for reviewSubject termIntervention termcombine with ORANDcombine with ORTropic* biodiversitySpecies richnessInvas* plantnon native plantexotic plantalien plantintroduced plantSearch term combinationsTable 3 Search term combinations and no of hitsKey word 1Key word 2Total hits(Topic search) lissom hits inWeb of learningTropic* biodiversityANDInvas* plant54Tropic* biodiversityANDNon native plant32Tropic* biodiversityANDexotic plant74Tropic* biodiver sityANDalien plant63Tropic* biodiversityANDnon-indigenous plant07Tropic* Species richnessANDInvas* plant38Tropic* Species richnessANDNon native plant30Tropic* Species richnessANDexotic plant60Tropic* Species richnessANDalien plant34Tropic* Species richnessANDnon-indigenous plant04tropical biodiversityAND(exotic plant) OR (invasive plant) OR(non native plant) OR (non indigenous plant)7,109425No of hits and the retrieval of relevant literature varies between the data base searches, in the above table hits obtained by web of science is mentioned as an example. The same search tem combination give quite different hit in another database search, for example, for the first search term tropic*biodiversity AND invas*plant Cab direct retrieved 56 articles.In addition to the web of science the search databases mentioned in section 3.1.1 have been used in the preparation of this protocol and will to a fault be used in final systematic review.3.1.3 Specialist web sources will be conductedwww.co nservationevidence.comwww.conserveOnline.orgwww.conservationevidence.orgwww.invasivespeciesinfo.gov3.1.4. Internet SearchThe internet will be searched victimisation the search engines. The first70 hits for each search will be recorded and examined for relevance.www.google.comwww.scholar.google.comwww.scirus.comwww.scientific.thomsonwebplus.com3.1.5 Specialist agencies and organization data searchAt global levelFood and Agriculture Organization of the United Nations (FAO)IUCN/Invasive species specials groupCABI- invasive species compendiumConvention on biological diversity (CBD)International mint Science Society (IWSS)UNEP-World Conservation Monitoring Centre (WCMC)Global Invasive Species Information Network (GISIN)Global Invasive Species Programme (GISP)In addition to this regional level agencies and organization in tropical countries will also consulted.AsiaAssociation of entropyeast Asian Nations , Regional Centre for Biodiversity Conservation (ARCBC)Invasive Alien Flora of Ind iaWeed Science Society of JapanWeed Science Society of ChinaAsia-Pacific Forest Invasive Species Network (APFISNAsia-Pacific Forest Invasive Species Network (APFISN)AustraliaInvasive Species CouncilSouth AmericaInter-American Biodiversity Information Network IABN Invasive Information Network3.2. champaign Inclusion criteriaThe relevant studies (articles, literatures, book sections) to be included in meta-analysis will be based in hierarchical judgment by first scanning the article titles followed by key words, abstracts and full text. The relevancy is determined by criteria as described below. If the data presented in the studies are not clear and needed to take more detailed description original authors and their respective organization will be contracted. Kappa analysis will be carried out for repeatability. Disputes between two reviewers will be solved by third independent reviewer.Geographical statusStudy area of the relevant studies should be within the tropics (23.438S to 1 37 23.438N).3.2.1. Relevant subjectsAny studies related to biodiversity changes in the tropical zone because of invasive plant species.3.2.2. Types of interventionInvasion of the tropical zone (forest land, agriculture land, grass land or savannas) by invasive plant species3.2.3. Types of comparatorsAny relevant studies and studies comparing the biodiversity of the tropical zone assessing before and after the effect of invasive plant species3.2.4. Types of outcomesAny guinea pig which shows biodiversity change (indicators like relative species richness or abundance)3.2.5. Types of studiesAny study which describes qualitatively or quantitatively the effect of invasive plant species in the biodiversity (species richness, abundance) in forest land, grassland. Range land, agriculture land, savannas. Those studies which present comparison of before and after the invasion or the comparison of the proportion of exotic species to native species will be included. Studies can be articles in peer reviewed journals, book chapters or grey literatures3.3. Potential effect modifier and reasons for heterogeneityDifferent edaphic, biotic, topographic and climatic condition which governs the vegetation type of the tropics such as soil quality, altitude, aspects, forest types and intensity of human disturbances which may respond to plant invasions in different ways affect the study outcomes. Furthermore, the biological characteristics of the invasive species also affect the study.3.4. Study quality assessmentThe searched articles, grey literatures and documents will be assesses according to the previously designed study inclusion criteria. These are then checked independently for validity, dependableness and applicability. A Quality assessment checklist is developed as shown below with the consultation of the review team and will be amended after stakeholders feedbacks. Internal and outer validity will be checked using a set of criteria.Table 4 Quality assessment checklist fo r checking validity, reliability and applicabilityVariablesYesNo1Target population and intervention defined2Sample representative3Experimental design/randomization4Base line information5Valid data collection6Description of confounding factors7Applicability of the research8Any biasesSource Adapted from enlighten notes, 2010 and literature review3.5. Data extraction strategyQualitative and quantities information will be extracted from the studies included for the review. Information on invasive species, their effects on tropical biodiversity (species richness, abundance and competition) will be extracted in to a specially designed extraction form as shown in annex-1. Where data are available, data will be extracted as before and after data and other data will be extracted as appropriate.3.6. Data synthesis and presentationData synthesis method will be determined by the availability of the data and data type. The studies will be grouped according to the type of information available e .g. review article, original research. If sufficient quantitative information is available meta-analysis will be conducted to know the significance of the effect of invasive plant species to the tropical biodiversity. If in sufficient quantitative information is available qualitative analysis of evidence will be undertaken.
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