An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien species.Despite the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana.In this study,we investigated the impact of invasive plants on the regeneration of forests dominated by K.evelyniana,a subtropical relict species in southwestern China.For this purpose,we characterized forest dynamics of 160 forest plots featuring K.evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K.evelyniana.We identified four distinct forest types in which K.evelyniana was dominant.We found that radial growth of K.evelyniana trees is faster in younger ageclasses today than it was for older trees at the same age.The population structure of K.evelyniana in each forest type exhibited a multimodal age-class distribution.However,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina adenophora.This invasive species resulted in a reduction of understory species diversity.Additionally,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern Yunnan.This suggests closely related invasive species face heightened competition,hindering successful invasion.Taken together,our findings indicate that successful establishment and habitat restoration of K.evelyniana seedling/saplings require effective measures to control invasive plants.

Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City

[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 families.In terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the total.The most alien invasive plants were native to America,accounting for 66.1%of the total.In terms of introduction path,the plants introduced artificially and unintentionally accounted for almost half.The species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and protection.There was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and protection.Among the 56 alien invasive plants,3 plants were toxic.From the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants.

Intelligent Fish Behavior Classification Using Modified Invasive Weed Optimization with Ensemble Fusion Model

Accurate and rapid detection of fish behaviors is critical to perceive health and welfare by allowing farmers to make informed management deci-sions about recirculating the aquaculture system while decreasing labor.The classic detection approach involves placing sensors on the skin or body of the fish,which may interfere with typical behavior and welfare.The progress of deep learning and computer vision technologies opens up new opportunities to understand the biological basis of this behavior and precisely quantify behaviors that contribute to achieving accurate management in precision farming and higher production efficacy.This study develops an intelligent fish behavior classification using modified invasive weed optimization with an ensemble fusion(IFBC-MIWOEF)model.The presented IFBC-MIWOEF model focuses on identifying the distinct kinds of fish behavior classification.To accomplish this,the IFBC-MIWOEF model designs an ensemble of Deep Learning(DL)based fusion models such as VGG-19,DenseNet,and Effi-cientNet models for fish behavior classification.In addition,the hyperparam-eter tuning of the DL models is carried out using the MIWO algorithm,which is derived from the concepts of oppositional-based learning(OBL)and the IWO algorithm.Finally,the softmax(SM)layer at the end of the DL model categorizes the input into distinct fish behavior classes.The experimental validation of the IFBC-MIWOEF model is tested using fish videos,and the results are examined under distinct aspects.An Extensive comparative study pointed out the improved outcomes of the IFBC-MIWOEF model over recent approaches.

Investigation and Hazard Assessment of Invasive Alien Plants on the Campus of Tongren University

[Objectives]The paper was to investigate and assess the species,distribution and hazard status of invasive alien plants on the campus of Tongren University.[Methods]A survey was conducted using line survey method,and the risk assessment index system of invasive alien plants was established by analytic hierarchy process(AHP).[Results]There were 11 species of invasive alien plants on the campus of Tongren University,belonging to 8 genera and 5 families.There were 6 species of invasive alien plants belonging to Asteraceae,accounting for 54.55%of the total.In terms of the origin of invasive plants,most of them were native to North America and Europe,accounting for 27.27%of the total.In terms of harmful level,there were no high-risk invasive plants on the campus of Tongren University,but Alternanthera philoxeroides had the highest score and was the most harmful.[Conclusions]The present situation of alien plant invasion on the campus of Tongren University is closely related to the ecological environment of the campus.It is suggested to strengthen the management of campus plants,focus on the prevention and control of A.philoxeroides,and carry out regular investigation of invasive alien plants on campus to ensure the ecological safety of the campus.

Detecting the distribution of and public attitudes to charismatic alien species based on media coverage

Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management.

Investigation and Risk Assessment of Alien Invasive Plants in Riparian Zone of Dongjiang River

[Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling plots investigation and route survey,and the whole Dongjiang River was covered.52 sampling points were set in the main streams,and 87 sampling points in tributaries streams,624 quadrats were set in total;multi-index comprehensive evaluation method was adopted for the risk assessment with 6 first-level indexes and 25 second-level indexes.[Result] Through the investigation on the riparian zone of Dongjiang River for 2 years,51 species of alien invasive plants were found,belonging to 17 families and 38 genera.The risk level assessment results of these 51 species showed that 18 species,such as Ageratum conyzoides,belonged to high-level risk with over 60 points;26 species,such as Chenopodium ambrosioides,were between 30 and 60 points which belonged to middle-level risk;7 species,such as Paspalum dilatatum,with less than 30 points belonged to low-level risk.[Conclusion] Basic data on the protection,water environmental management and functional zoning of riparian zone of Dongjiang River were provided.

A Study on Alien Invasive Plants from the Interactive Mechanism between Species Niche and Material/Energy Flow

[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.

Control Effect of Several Replacement Plants on Invasive Weed Eupatorium adenophorum Spreng

To select the suitable plant species controlling Eupatorium adenophorum in hilly area, ecological adaptability, competitiveness and control efficacy of many replacement plants with economic value in Guizhou Province of China were studied. The results showed that the coverage of paspalum wetsfeteini and Dolichos lablab were 100% and 93%, which increased by 3.70 and 3.44 times compared with Lolium perenne, respectively; their relative crowding coefficient with E. adenophorum were 7.09 and 22.78, which increased by 2.43 and 7.80 times compared with L perenroe, respectively. Using excavation method, the control efficacies of replacement plants were 99.3 % and 96.9%, respectively, while the control efficacy of replacement plants using mowing method was lower than 66.4%. The overwintering rate of P. wetsfeteini in the following year was 95% ; its coverage was still 100% and its control efficacy against E. adenophorum remained over 99%. D. lablab was difficult to survive the winter in the north region beyond 26.2°N, so it could only be applied as annual replacement plant. The coverage of Setaria anceps, Cajanus cajan and other test plants were less than 90%, with poor control efficacy against E. adenophorum.

Study on the Allelopathic Effects of Alien Invasive Species Cenchrus echinatus on Seed Germination and Seedling Growth of Solanaceae Crops

[Objective] This study aimed to investigate the potential ecological dam- ages of alien invasive species Cenchrus echinatus. [Method] By using seed germi- nation method, the effects of different concentrations of C. echinatus aqueous extracts on seed germination and seedling growth of three Solanaceae crops were investigated. [Result] After incubated for 5 d, no significant differences were observed in germination speed indices of Lycopersicum esculentum seeds between aqueous extract groups and control groups; germination speed indices of Solarium melongena seeds were significantly reduced with the increasing concentration of Cenchrus echinatus aqueous extracts; however, Capsicum frutescens seeds in various groups were not germinated. After incubated for 7 d, root lengths of Lycopersicum esculentum seedlings were inhibited with the increasing concentration of Cenchrus echinatus aqueous extracts, while stem lengths and comprehensive allelopathic effects were promoted; germination rates of Solanum melongena seeds in various groups were all significantly lower than control groups; root length, stem length and comprehen- sive allelopathic effects in higher concentration groups were inhibited; germination rates of Capsicum frutescens seeds were significantly inhibited, and those in the highest concentration group were not generated. After incubated for 14 d, all indica- tors of Solanum melongena were significantly inhibited; various indicators of Capsicum frutescens in the highest concentration group were significantly inhibited. [Conclusion] The sensitivity of three Solanaceae crops to Cenchrus echinatus aqueous extracts presented an overall order of Solanum melongena 〉 Capsicum frutescens 〉 Lycopersicum esculentum, suggesting that Cenchrus echinatus can to some extent inhibit the growth of several crops, which should be strictly prevented and controlled in agricultural production.

Alien invasive species in Siberia:current status and problem

Although alien and invasive plant species have been researched extensively in the European part of Russia,the situation in Siberia is another matter.Hitherto,alien and invasive species in Siberia have not received much attention because this problem was not especially acute in Siberia.The lack of attention on alien and invasive species in Siberia is attributed to three major reasons：1） Low vegetative productivity and sparse human populations in the Siberian territory have limited botanical research interest in the area.2） Severe Siberian climate likely prevents many alien and invasive species from increasing their distribution into Siberia.3） Most Siberian plant communities have not been human-transformed and thus may be resistant to newcomers.Nevertheless,recent increased economic activities have resulted in increasing plant migration to Siberia,and this process should be monitored.Furthermore,global environmental changes may also have made Siberia more favorable for more alien and invasive species.Currently,research on alien and invasive species has begun in the Altai-Sayan region（Western Siberia） and the Magadan region （Northeastern Asia）.

Predicting suitable habitat of an invasive weed Parthenium hysterophorus under future climate scenarios in Chitwan Annapurna Landscape,Nepal

Chitwan-Annapuma Landscape(CHAL)in central Nepal is known for its rich biodiversity and the landscape is expected to provide corridors for species range shift in response to climate change.Environmental assessments have identified biological invasions and other anthropogenic activities as major threats to the biodiversity in the CHAL.One of the rapidly spreading Invasive Alien Plant species(IAPs)in the CHAL is Parthenium hysterophorus L.,a neotropical invasive weed of global significance.This study aimed to investigate the current and future projected suitable habitat of P.hysterophorus in the CHAL using MaxEnt modelling in three'Representative Concentration Pathways'(RCPs 2.6,4.5 and 8.5)corresponding to different greenhouse gases emissiontrajectories for the year 2050 and 2070.A total of 288species occurrence points,six bioclimatic variablesmean diurnal range,isothermality,annual precipitation,precipitation of driest month,precipitation seasonality,precipitation of driest quarter and two topographic variables(aspect and slope)were selected for MaxEnt modelling.Potential range shift in terms of increase or decline in the suitable habitat areas under the projected scenarios were calculated.Slope and annual precipitation were the most important variables that explained the current distribution of P.hysterophorus.Twenty percent of the total area of CHAL was predicted to be suitable habitat for the growth of P.hysterophorus in the current climatic condition.Highest gain in the suitable habitat of this noxious weed was found under RCP 4.5 scenario in 2050 and 2070.whereas there will be a loss in thesuitable habitat under RCP 8.5 scenario in 2050 and2070.Out of four physiographic regions present in CHAL,three regions-Siwalik,Middle Mountain and High Mountain have suitable habitat for P.hysterophorus under current climatic condition.The mountainous region is likely to be affected more than the Siwalik region by further spread of P.fhysteropfhorus in the future under low(RCP 2.6)to medium(RCP 4.5)emission scenarios.The suitable habitat for this weed is likely to increase in the protected areas of mountain regions(Langtang National Park,Annapurna Conservation Area and Manaslu Conservation Area)in the future.The results have revealed a risk of spreading P.hysterophorus from present localities to non-invaded areas in the current and future climatic condition.Such risk needs to be considered by decision makers and resource managers while planning for effective management of this weed to reduce its ecological and economic impacts in the CHAL.

Invasive Alien Plants of Indian Himalayan Region—Diversity and Implication

The present study deals with comprehensive list of Invasive alien plants of Indian Himalayan Region with background information on family, habit and nativity. A total of 190 invasive alien species under 112 genera, belonging to 47 families have been recorded. Among these, the dicotyledons represent by 40 families, 95 genera and 170 species;monocotyledons represent by 7 families, 17 genera and 20 species. The analysis of invasive species reveals that 18 species have been introduced intentionally, while the remaining species established unintentionally through trade. In terms of nativity, amongst 13 geographic regions, the majority of invasive plants reported from American continent (73%). While in life form analysis, the herbs (148 species) are dominant, followed by shrubs (19 species), Grass (11 species), Trees (4 species), sedges and climber (3 species each). Most of the invasive species are annual habit (63%). Apart from these, 90 species (47%) are being used by locals for medicinal purposes. A better planning is needed for early detection to control and reporting of infestations of spread of new and naturalized weeds to be monitored.

Changes in Soil Biota Resulting from Growth of the Invasive Weed, Ambrosia artemisiifolia L.(Compositae), Enhance Its Success and Reduce Growth of Co-Occurring Plants

Exotic plant invasion presents a serious threat to native ecosystem structure and function. Little is known about the role of soil microbial communities in facilitating or resisting the spread of invasive plants into native communities. The purpose of this research is to understand how the invasive annual plant Ambrosia artemisiifolia L. facilitates its competition capacity through changing the structure and function of soil microbial communities. The soil characteristics of different areas invaded by A. artemisiifolia were examined. Greenhouse experiments were designed to assess the effect of A. artemisiifolia invasion-induced changes of soil biota on co-occurring plant growth, and on the interactions between A. artemisiifolia and three co-occurring plant species. The results showed that the soil organic C content was the highest in heavily invaded sites, the lowest in native plant sites, and intermediate in newly invaded sites. Soil available N, P and K concentrations in heavily invaded site were 2.4, 1.9 and 1.7 times higher than those in native plant soil, respectively. Soil pH decreased as A. artemisiifolia invasion intensity increased, and was lower in invaded sites（heavily invaded and newly invaded） than in native plant sites. The soil microbial community structure was clearly separated in the three types of sites, and A. artemisiifolia invasion increased anaerobe, sulfate-reducing bacteria and actinomycete abundance. Soil biota of invaded sites inhibits growth of co-occurring plants（Galinsoga parvifloraCav., Medicago sativa L. and Setaria plicata（Lam.） T. Cooke.） compared to soil biota from un-invaded sites, but facilitates A. artemisiifolia growth and competition with co-occurring plants. A. artemisiifolia biomass was 50-130% greater when competing with three co-occurring plants, compared to single-species competition only（invasion by A. artemisiifolia alone）, in heavily invaded soil. Results of the present study indicated that A. artemisiifolia invasion alters the soil microbial community in a way that favors itself while inhibiting native plant species, with measurable effects on performance of co-occurring plants.

The Distribution and Problems of the Invasive Alien Plant, <i>Mimosa diplotricha</i>C. Wright ex Sauvalle (Mimosaceae) in Nigeria

Mimosa diplotricha is an invasive perennial, scrambling, thorny, leguminous shrub of neotropical origin widely acknowledged as a major economic, agricultural and ecological burden in its introduced ranges. Although the plant is thought to have been present in Nigeria for well over two decades, its mode and time of introduction is uncertain. In spite of the continuing spread of, and the menace caused by M. diplotricha in Nigeria, no attempt has been made to map the distribution of the plant countrywide. Therefore, we conducted a countrywide survey between 2007 and 2009, sponsored by the Weed Science Society of Nigeria (WSSN) to determine the spread and status of Mimosa diplotricha in Nigeria. A further objective of this paper was to review literatures on Mimosa diplotricha in Nigeria and elsewhere to enable comparison. In this paper, we report on the spread, distribution and problems of Mimosa diplotricha in Nigeria based on the field monitoring surveys conducted. The distribution of this invasive plant in Nigeria has been mapped and is presented together with its ecology and problems being caused. Since the early 1990s, the weed has started to spread and invade many parts of the country causing significant damage to many natural and semi natural ecosystems. The different control options used by farmers to control Mimosa diplotricha in Nigeria are discussed. Based on the successful control of this invasive plant using the biocontrol agent, Heteropsylla spinulosa in countries such as Australia and Papua New Guinea (PNG), we discussed the biological control prospects for the management of Mimosa diplotricha in Nigeria. Such control attempts stands to benefit from international collaborations between Nigerian institutions and a host of others in Australia, PNG and/or Brazil. Finally three major causes for the massive and continuing spread of this weed in Nigeria are presented with recommendations for the Nigerian government and institutions to: 1) formulate policies and legislations regarding the control and management of invasive alien plant species which is currently nonexistent;2) enlighten the general public on the dangers of invasive alien plant species such as Mimosa diplotricha;and 3) initiate actions such as early detection and rapid response (EDRR) and biological control in order to prevent further spread of, and invasion by invasive plant species including Mimosa diplotricha.

InvasionDB: A genome and gene database of invasive alien species

Invasive alien species(IAS) are species whose introduction to areas outside of their native range cause harm to economics, biodiversity, and the environment. Understanding the genetic basis of invasiveness is critical for preventing invasion by an alien species and managing IAS with eco-friendly control methods. In addition, uncovering the genomic features of IAS is essential for accurately predicting invasiveness. However, even though increasing efforts have been devoted to sequencing the genomes of IAS, there is still not an integrated genome database for the invasive biology community. Here, we first determined a list of invasive plants and animals by mining references and databases. Then, we retrieved the genomic and gene data of these IAS, and constructed a database, Invasion DB. Invasion DB encompasses 131 IAS genomes, 76 annotated IAS assemblies, and links these data to conventional functions such as searching for gene coding sequences and Pfam, KEGG, NR annotations, BLAST server, JBrowse, and downloads services. Next, we analyzed 19 invasivenessrelated gene families which confer invasiveness in insects. To study the roles of noncoding RNA in invasiveness, we also annotated 135 494 mi RNAs, 89 294 r RNAs, and 2 671 941 t RNAs from these IAS. In summary, Invasion DB is useful for studying the invasiveness at the genomic level, and thus helps to develop novel management strategies to control IAS.

Survey and Analysis on Alien Invasive Plants of Jinziling Scenic Spot in Pingle County

According to the field survey of alien invasive plants of Jinziling,there were 23 kinds of alien invasive plants in the scenic spot.Species with the comprehensive dominance degree higher than 10% were as follows: six kinds of Asteraceae: Bidens pilosa,Aster subulatus,Ageratum conyzoides,Conyzai canadens,Parthenium hysterophorus,and Conyza sumatrensis; two kinds of Gramineae: Axonopus compressu,Eleusine indica; two kinds of convolvere: Ipomoea nil,Ipomoea purpurea; two kinds of Fabaceae: Cassiae tora,Medicago hispida; one kind of Verbenaceae: Lantana camara; one kind of Euphorbiaceae: Euphorbia hirta.In total,there were 14 kinds of alien invasive plants.In this survey,the dominant species of invasive plants were obtained by statistical analysis of the composition and distribution of the invasive plants,and the invasion trend was predicted,so as to take effective and economical management and control measures.

Invasive Weed Mapping of Lebanon

Surveying and early detection of invasive weeds are essential for strategic management and monitoring. Accordingly, a weed mapping was conducted during July 2011, against native （Orobanche ramosa, Cuscuta spp., Sorghum halepense and Xanthium strumarium） and non native （Abutilon theophrasti, Datura stramonium, Solanum elaeagnifolium and Verbesina encelioide） weeds of Lebanon. A global positioning system （Garmin 2006） was used for precise waypoint, elevation, navigation and distance. The result of interviewing and interacting with the residents in 95 villages distributed between the Beq＇aa and the North governorates of Lebanon, along with the observations made on the route, yielded the first detection of Abutilon theophrasti in both governorates. Solanum elaeagnifolium and Verbesina encelioide were not found in the agro-ecosystems of either governorates. This is the first report of the introduction ofAbutilon theophrasti in Lebanon and the establishment of a baseline data on weeds of Lebanon. The adoption of an integrated weed management program with a quarantine and control techniques and methods is needed to manage the spreading of weeds and to lessen their ability to adapt to a constantly changing system which uses several control practices.

Ambrosia Artemisfifolia L. Invasive and Allergic Weed Species on the Territory of Novi Sad

During three years lasting studies on the territory of the city of Novi Sad, terrain studies of Ambrosia artemisiifolia L. distribution as well as mapping were performed on regulated and disordered green areas and on arable areas. For mapping of ragweed distribution, partially modified method of Braun-Blanquet was used, and data processing was perfomed by specially designed program Ambrosia Spot Marker. Monitoring of this species was also done because of the occurrence of retrovegetation after mowing. During vegetation period, this allergenic weed species was controlled by multiple mowing, and rough ruderal sites outside settlements were treated by glyphosate at a rate of 1.2 kg ha^-1 -2.4 kg ha^-1. The study comprehended also monitoring of pollen concentrations in the air by Rotorod pollen sampler spore collector. A. artemisiifolia L. was established in 21 city zones on over 200 localities, on the banks of the river Danube, in Petrovaradin and Sremski Karlovci. Recommended mechanical measures such as mowing, drilling in the phase of germination, and chemical control measures, resulted in significant reduction ofA. artemisiifolia L. In the second half of the August 2009 the highest number of pollen grains was found in the amount of 783 pollen grains per m3 of air.

Uses of Invasive Alien Plant Species in Rema-Kalenga Wildlife Sanctuary of Bangladesh

An exploratory survey was conducted on the uses and role of invasive alien species(IAS) to local livelihoods in the Rema-Kalenga Wildlife Sanctuary in the northeastern hilly region of Bangladesh.Vegetation was sampled in 50 quadrates,each 10 m×10 m,and 25 line transects,each 50 m×20 m,through a combination of random and systematic sampling.Group discussions were also arranged with fifty local inhabitants(17 % of the total inhabitants) to learn the various uses of IAS.A total of 17 alien plant species belonging to 10 different families,of which Leguminosae constitutes the highest number(5 species),include tree(53%) followed by herb(12%),shrub(12%) and others(weed,climber and palm).The majority of the identified species were found to be used for fuel,followed by timber production,medicinal or curative uses,fodder,and many others.In addition to providing various forest products,alien tree species planted in forest plantation help provide many vital ecosystem services such as soil amelioration through nitrogen fixation.It is true that the alien species have some negative impacts on local ecosystems,and not all of them are harmful.Therefore,a national programme must be initiated to distinguish the harmful from the harmless species and to identify the uses and impacts of the former and latter.

Environmental Impacts of Invasive Alien Plant Species on the Biodiversity of the Nyika National Park, Rumphi District, Malawi

Invasive alien plant species have threatened the integrity of ecosystems and threatened biological integrity throughout the world. In the Nyika National Park, a number of alien invasive plant species have been reported. These invasive alien plants are reported to be very difficult that have caused adverse ecological, economic and social impact. The main objective of this study is to assess the environmental impact of plant invasive alien species in Nyika National Park in order to ascertain means of addressing the possible effects on the biodiversity. This study adopted an exploratory stance in order to answer the hypotheses where purposive and simple random sampling was used. Purposive sampling was only used to the staff of Nyika while simple random sampling was used to collect data from households surrounding Nyika National Park. The results revealed that invasive alien plant species have some ecological impacts of on the biodiversity of the Nyika National Park like change in physical habitats such as loss of native habitats, alteration of ground water regime, drying of rivers, loss of native species and alteration of biomass. The study would therefore be important to policy makers in guiding and development of policies and guidelines governing eradication of invasive alien plant species. The Department of National Parks and Wildlife (DNPW) can form partnership with various stakeholders with a clearly stated intention of developing a relationship, based on collaboration to enhance the control of invading alien plant species and the best management practices.