Invasive alien plants in Polish national parks—threats to species diversity

Ecological impact of phytoinvasions in Ukraine

Distribution and management of invasive alien plant species in protected areas in Central Europe

ARTICLE HIGLIGHTS- A pioneering study of invasive alien plant species in the riparian areas of Northern Samar- Species composition, endemism, and conservation status of introduced species- Out of 65 introduced species, 32 were listed as invasiveABSTRACTRiparian areas are highly dynamic and naturally disturbed, making them particularly susceptible to invasion. Invasive Alien Plant Species (IAPS) are widely distributed in these areas due to the favorable environmental conditions that support their growth and persistence. This study is a pioneering effort to document the invasive alien plant species thriving in the riparian zones of Allen, Biri, Catarman, Gamay, Mapanas, Laoang, Lapinig, Las Navas, and Pambujan in Northern Samar. Sampling was conducted from March to December 2023. Six transect lines, each measuring two kilometers per site, were established in the riparian areas to identify existing invasive alien plants. In total, 60 transect lines were set up across all sampling areas. As a result, 65 introduced plant species belonging to 24 families and 56 genera were documented in the riparian areas of Northern Samar. The families with the highest number of species were Poaceae (13 spp.), Asteraceae (12 spp.), Cyperaceae, Fabaceae, and Lamiaceae (5 spp. each). The remaining families had fewer than five species each. The most common invasive plant species recorded was Psidium guajava L., which was present in all sampling areas. Based on life forms, the study identified two tree species, 17 shrubs, three vines, one epiphyte, and 42 herbs. Conservation status was determined using the latest IUCN and DENR listings (2017–11). One taxon was classified as Data Deficient, 32 as Least Concerned, and the remaining species as Not Evaluated. In contrast, no taxa were assessed in the DENR 2017–11 listing. Furthermore, of the 65 introduced plant species documented, 10 were recorded as invasive in the Global Invasive Species Database, while 22 were listed in the Global Register of Introduced and Invasive Species Database. Although invasive alien species have long been recognized as posing serious threats to human health, forestry, agriculture, fisheries, and natural biodiversity, no comprehensive assessment of their status, trends, causes, impacts, management, and governance issues has been conducted worldwide. Thus, this study aimed to supplement existing data on invasive plants and assist policymakers in developing policy frameworks for managing invasive alien plant species to mitigate their impacts on human health and the environment.

Extent of plant invasions has been expected to be low in protected areas such as national parks due to low anthropogenic activities and high wilderness. However, recent researches across the world have revealed that plant invasions can be severe in the national parks with negative impacts on the protected species and ecosystems. Unfortunately, the status of plant invasions in the national parks of Nepal is mostly unknown. In this study, we sampled at seven locations inside the Parsa National Park (PNP) to document diversity and abundance of invasive alien plant species (IAPS) and their impacts on tree regeneration. Altogether, 130 quadrats of 10 m × 10 m were sampled. We recorded 14 IAPS in the PNP. Three of the IAPS (Chromolana odorata, Lantana camara and Mikania micrantha) were among the 100 of the world’s worst invasive alien species. C. odorata was found to be the most frequent IAPS with the highest cover. The frequency and cover of the IAPS were higher at the sites close to the settlements than at the sites away from the settlements. The species richness of the IAPS was also higher at the sites closer to the settlements than away. The sapling density of the tree species was found to have declined with the increasing cover of the IAPS suggesting that the IAPS had negatively affected tree regeneration. Our data revealed that the PNP has already witnessed massive plant invasions with widespread occurrence of three of the world’s worst invasive species. Therefore, it is high time to integrate management of invasive alien species in the management plan of the park.

Abstract. Huda MK, Pasaribu N, Syamsuardi, Siregar ES. 2022. Diversity, risk and management feasibility of invasive alien plants in the border zone of Sicike-cike Nature Tourism Park, North Sumatra, Indonesia. Biodiversitas 23: 3156-3165. Invasive alien species (IAS) threaten native ecosystems and biota either directly or indirectly. Once colonizing, invasive plant species tend to dominate a landscape, hindering other native vegetation from growing. Thus, the invasion of alien plant species needs attention moreover in protected areas such as Nature Tourism Park (Taman Wisata Alam/TWA) Sicike-cike, Dairi District, North Sumatra, Indonesia. Besides its importance for nature conservation, TWA Sicike-cike is culturally essential for Pakpak Dairi ethnic community as well as economically for ecotourism. Yet, anecdotal evidence showed the presence of several invasive alien plants around the park. This study aimed to investigate the diversity and composition of invasive alien plants within the vegetation community in TWA Sicike-cike and to assess the risk value and management feasibility of the IAS. Purposive sampling using line transect method was conducted to collect data with a total of 120 observation plots established along 6 transects. Risk value was assessed based on invasiveness, impact and potential distribution. Management feasibility was assessed based on cost, current distribution and persistence. The results showed that Asteraceae was the most dominant family of invasive plants in the studied area with four species. At the species level, Imperata cylindrica was invasive alien plant species with the highest important value index (IVI) of 57.65% and a high-risk value of 235.8, followed by other species including Ageratum conyzoides, Chromolaena odorata, Clidemia hirta and Melastoma malabathricum. In terms of management feasibility, the existence of I. cylindrica is recommended for direct eradication, while other IAS management recommendations, included monitoring and area protection for further invasion by the species.

Non-native plants that can cause adverse effects are otherwise known as invasive alien plant species which pose a major threat to plant biodiversity conservation and sustainability. This study is dedicated to determine the plant diversity and to assess the vulnerability of Quezon Protected Landscape, Southern Luzon, the Philippines to invasive alien plant species. Data from 90 10x10 m randomly established plots using the quadrat method showed that there are 318 plant species wherein 208 are native, 100 are non-native, and 10 are invasive. Results from the association of the physicochemical factors and the presence of invasive alien plant species through Spearman rho test revealed that most of the physicochemical factors have significant association except percent slope and hill shade. Soil pH, aspect and number of non-native plants show positive association while soil moisture, leaf litter thickness, elevation, species richness, species evenness, plot species diversity index, and the number of native plants signify negative association. Differences between the plots of with and without invasive alien plant species in physicochemical factors indicate that most of the physicochemical factors have a significant difference between plots of with and without invasive alien plant species except percent slope, hill shade, and aspect. Lastly, the MaxEnt model exemplifies that the most suitable predicted conditions for invasive alien plant species are at the edges of boundary and buffer zones. This study implies that most of the physicochemical factors are linked to the presence of invasive alien plant species and Quezon Protected Landscape has a low vulnerability to invasive alien plant species invasion.

Habitat degradation due to invasive plant species is identified as one of themajor threats in several protected areas managed by Department of WildlifeConservation in Sri Lanka. Bundala National Park, covering an area of 6216ha is located about 250 km Southeast of Colombo (06°08' - 06°14' N, 81°08'- 81°18'). The Bundala National Park is Sri Lanka's first Wetland ofInternational importance declared under the Ramsar Convention. The parkconsists of mainly dry thorny scrubland and lagoons, which are shallowbrackish water lagoons. They harbours a rich bird life including severalspecies of migratory waterfowls. It also contains key nesting sites for fivespecies of marine turtles. Arid and semiarid terrestrial habitats shelter a widerange of species, including elephants and other mammals, reptiles,amphibians and fish species. The introduced Prosopis julifolia, a tree speciesnative to Central and South America as a fuel wood in home gardens by theForest Department has expanded its distribution and has invaded the BundalaNational Park. There are large stands of Prosopis julifolia that prevents thegrowth of other indigenous species. Furthermore it invades the lagoon and asa result the area covered by the lagoon is also being reduced. Opuntia strictavar. dillenii, which is also a plant native to Central America, is used mainlyas a hedge species around human dwellings and from there it may haveinvaded wetland habitats in Bundala National Park. The spread of these invasive alien plant species has resulted in theprogressive deterioration of wildlife habitats and native biodiversity in thepark, and hence warranting immediate management to curtail their spread.The general methodology adopted for the invasive plant managementprogramme in Sri Lanka is based on adaptive management techniques.Adaptive management is a process that involves planning, management andmonitoring to provide a framework for testing assumptions, adaptation andlearning. Invasive species were eradicated manually and mechanically. Lackof a planned systematic research programme to compile field observations inareas subjected to invasive plant management is a major constraint. Inaddition, views of non-scientific public and lack of funds for adaptivemanagement techniques are the major constraints

Indonesia has tremendous biodiversity, and one of its species is invasive alien plants that invade other ecosystems. Invasive species have various characteristics, usually dominate new ecosystems, and are difficult to control. Invasion of alien species occurs in forest ecosystems, aquatic ecosystems, coastal ecosystems, oceans, and rice fields, but usually in changed ecosystems. This study aims to record the spread of invasive alien plant species, influencing variables, effects, and successful control strategies in Indonesian ecosystems. The methodology used was a systematic literature review (SLR), which included preparation, execution, and reporting. This study found 13 families and 23 species. The Compositae, Fabaceae, and Asteraceae families were the most abundant known ecosystems. The forest is the ecosystem most dominated by invasive alien plants. Several factors cause the environment to be damaged, which affects the ecosystem, and the ingredients used for medicine, house construction, and food. Efforts to control invasive alien plant species through invasive plant risk assessment, eradication, ecosystem restoration, and awareness of invasive plant species and their dangers to the surrounding community. Future research is to conduct appropriate conservation for ecosystems damaged by invasive alien plants.

SummaryBiological invasions and climate warming are two major threats to the world's biodiversity. To date, their impacts have largely been considered independently, despite indications that climate warming may increase the success of many invasive alien species. We therefore set up an experiment to study competition between native and invasive alien plant species and the effects of climate warming thereon. Two highly invasive alien plant species in Belgium, each with a native competitor that dominated in invaded sites, were grown either together (1:1 mixtures) or in isolation (monocultures) at ambient and elevated temperature (+3°C) in climate‐controlled chambers. To detect possible mechanisms underlying the effects of competition and elevated temperature, we conducted a combined growth and nitrogen uptake analysis. In one pair, Senecio inaequidens – Plantago lanceolata (alien invasive – native), the alien species dominated in mixture, while in the other pair, Solidago gigantea – Epilobium hirsutum, the native species dominated. Climate warming reduced the invader dominance in the first species pair, but stimulated the suppressed invader in the latter. Many of the biomass responses for these two species pairs could be traced to the root‐specific nitrogen uptake capacity. The responses of the native‐invasive interaction to warming could not always be extrapolated from the monoculture responses, pointing to the necessity for experiments that take into account species interactions.

Gymnocoronis spilanthoides

The spread of invasive alien plants has considerable environmental and economic consequences, and is one of the most challenging ecological problems. The spread of invasive alien plant species depends largely on long-distance dispersal, which is typically linked with human activity. The increasing domination of the internet will have impacts upon almost all components of our lives, including potential consequences for the spread of invasive species. To determine whether the rise of Internet commerce has any consequences for the spread of invasive alien plant species, we studied the sale of thirteen of some of the most harmful Europe invasive alien plant species sold as decorative plants from twenty-eight large, well known gardening shops in Poland that sold both via the Internet and through traditional customer sales. We also analyzed temporal changes in the number of invasive plants sold in the largest Polish internet auction portal. When sold through the Internet invasive alien plant species were transported considerably longer distances than for traditional sales. For internet sales, seeds of invasive alien plant species were transported further than were live plants saplings; this was not the case for traditional sales. Also, with e-commerce the shape of distance distribution were flattened with low skewness comparing with traditional sale where the distributions were peaked and right-skewed. Thus, e-commerce created novel modes of long-distance dispersal, while traditional sale resembled more natural dispersal modes. Moreover, analysis of sale in the biggest Polish internet auction portal showed that the number of alien specimens sold via the internet has increased markedly over recent years. Therefore internet commerce is likely to increase the rate at which ecological communities become homogenized and increase spread of invasive species by increasing the rate of long distance dispersal.

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.

Invasive alien plant species: From the molecular to the economic approach Invasive alien species (IAS) are plants, animals, pathogens and other organisms that are not natural in a certain ecosystem and that can cause economic or environmental damage or adversely affect human health (Ljubojevićet al., 2022) . Plant invasiveness is a globally recognized environmental and economic problem (Bang et al., 2022) . Today, the loss of biodiversity occurs due to intensive anthropogenic activities, like over-exploitation of species, urbanization and industrialization, environmental pollution, land-use shift, the introduction of IAS as well as climate change (Ren and Duan, 2017) . IAS introduction has many advantages and disadvantages, leading to numerous ecosystem services and disservices. Fostered by climate changes (Kariyawasam et al., 2019) and inherited (inner) ability to adapt to various conditions, IAS treat to suppress natural vegetation. Theoharides and Dukes (2007) defined four main stages of invasion: introduction, naturalization, colonization, and dispersal. Milanovićet al. (2020) stated that alien (especially invasive) plant species differ from native species in different morphological characteristics such as specific leaf area, height, seed size or flowering duration, where invasive species showed significant dominance in the investigated characteristics. A list of invasion-promoting traits is being amended as novel research is being conducted, from seed characteristics (Ljubojevićet al., 2021) to the whole-plant level (Bajwa et al., 2016) . With such high adaptive potential alien species develop traits that allow them to successfully cope with the changes in climate or habitats (Dukes and Mooney, 1999) . However, being very adaptive, fast-growing, and not infrequently highly ornamental, those species provide numerous ecosystem services. If viewed exclusively as 'weeds' then many resources would be invested in the eradication measures of invasive alien species, with little certainty about the desired outcome. Thus, this Research Topic gathered recent findings from around the world, providing insight into differences in gene expression, morphology, physiology and resource utilization by invasive alien species, that provided them with successful habitat invasion. As shown by (Nunes et al.) weedy invaders spread rapidly due to successful adaptation and naturalization, affecting both natural and agricultural ecosystems. One of the most invasive weed species in the sub-tropical and continental climate is Arundo donax L. from Poaceae family. Owing to the chemical and histological modifications, this species successfully inhabit the Mediterranean basin. Another invasion pathway includes soil Frontiers in Plant Science frontiersin.org 01

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

Invasive process of alien species is affected by not only the invaded habitats, but also the surrounding landscape matrix. Understanding the effects of landscape matrix on alien species is of great significance for controlling invasive alien species. We surveyed plant communities along the water-level fluctuating zone (WLFZ) of the Three Gorges Reservoir. Invasive status of alien plant species was evaluated. Totally 10 spatial scales of the surrounding landscape matrix in the scope of 2000 m (including WLFZ) were classified, and 14 landscape indices were applied to analyze the landscape matrix composition and configuration. Using the principal component analysis and correlation analysis, the effects of landscape matrix on the alien invasive plant species and associated scale effect were tested. Results showed that a total of 42 alien invasive plant species were found in the WLFZ, belonging to 17 families and 36 genera. Fuling was a dividing place to differentiate invasive species distribution. The number of the alien invasive species between Fuling and the Three Gorges Dam was found more than that between Fuling and Jiangjin. For the all scales (within 2000 m). The higher the landscape matrix fragmentation was, the more difficult the alien species invading. The higher landscape connectivity was, the easier the alien species invading. The effects of landscape matrix composition and configuration on the invasive plant diversity at large scales (1200-2000 m) was more significant than those at small scales (200-1000 m), in which landscape matrix composition and configuration at 1200-1400 m showed the strongest effect, demonstrating a significant spatial scale effect. Different invasive plant species showed the scale effects of landscape matrix composition and configuration. At all scales, Xanthium strumarium and Bidens frondosa showed weak correlations with landscape indices, but Bidens tripartita and Erigeron canadensis showed strong correlations. Landscape matrix was closely related to invasive plant species, and demonstrated a significant scale effect. The alien invasive plant species could be traced to the landscape matrix at large scales. Grassland and forest patches at the small scales could be used as the 'stepping stone' for the alien species transiting before they arrived at the WLFZ. In order to control alien plants in the WLFZ, land-use management and optimization should be strengthened at different scales of landscape matrix on the basis of enhancement of habitat management. A diversified comprehensive control for alien species should thus be taken into account.