• Journal of Korean Society on Water Environment
• /
• v.33 no.3
• /
• pp.291-301
• /
• 2017

This study was carried out to investigate distribution on the alien plants in the Gyeong-in Ara Waterway. The alien plants were a total of 82 taxa: 17 families, 63 genera, 80 species, and 2 varieties. This number corresponds to 25.5% of alien plants identified in Korea. The proportion of alien plants in every year was increased from upstream to downstream. As the result of the analysis on vegetation stratification, bank of waterside was covered with artificial materials preventing existence of vegetation, and had step-type cross section. Floodplain was composed of waterfront area. An array of vegetation was not typical dispersion, and terrestrial and alien plants were dominated the Gyeong-in Ara Waterway. Evaluation of naturalness based on the vegetation stratification showed grade 3 or 4. In order to solve a problem, method and level of restoration should be decided based on the result of diagnostic assessment. Therefore, we need to restore the step-type cross section as pool type one. From waterside to bank in this waterway, we recommend to introduce natural plants by imitating reference species composition. Since, an invasion of alien plants is expected to be accelerated due to the continuous artificial disturbance, we recommend to quantitative investigation on the invasion of alien plants and monitoring on the change of distribution.

• Korean Journal of Plant Taxonomy
• /
• v.50 no.2
• /
• pp.89-119
• /
• 2020

Species invasions have rapidly increased due to the substantial growth of global trade in the recent past. As the awareness of the negative effects on natural ecosystems derived from alien species has grown, many countries and lawmakers have enacted rules and policies on the conservation of indigenous plants. Unfortunately, in Korea, research on species invasion is seriously lacking despite the growing number of alien species. In the current study, we report alien plants that have intentionally and/or unintentionally been introduced in Korea and also presented a checklist of invasive plants found both in the literature and in field surveys. We reviewed all documented records of alien plants, i.e., scientific papers, illustrated books, and annual reports. We also categorized alien plants by origin, time of introduction, naturalization, and the rate of their spread. The results revealed that there are 619 alien plant taxa (96 families, 353 genera, 595 species, 6 subspecies, 11 varieties, 1 forma, and 6 hybrids) occurring in Korea. Among these, 30 taxa are archaeophytes (Arc.), 214 are potentially invasive plants (PIPs), and 375 are invasive alien plants (IAPs). In addition, IAP taxa consist of grades 5 (widespread, WS) to 1 (potential spread, PS) of alien plants according to the rate of spread in Korea. Our results suggested that the number of alien plants is likely to keep growing; thus, the distribution should be regularly monitored and the list of alien plants must be updated.

• Journal of Ecology and Environment
• /
• v.45 no.4
• /
• pp.277-286
• /
• 2021

Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.22 no.6
• /
• pp.89-96
• /
• 2019

This study was carried out for management of the invasive alien plants in Mt. Inwang located in central Seoul. The invasive alien plants are 11 families, 34 genera, 30 taxa, and they are 10.8% of the total vascular plants(314 taxa). The ecosystem disturbed plants designated by the Korea environment ministry are 6 taxa : Rumex acetosella, Lactuca scariola, Ambrosia trifida var. trifida, Ambrosia artemisiifolia, Aster pilosus and Eupatorium rugosum. In the life-form, herbaceous perennials are 13 taxa(35.3%). In the continent of origin, the species from America are 20 taxa(58.8%). In the introduction time, the species of third period are 14 taxa(41.2%). In the diffusion grade, 5 grade species are 14 taxa(41.2%) and they are wide spread species. Mt. Inwang was designated as ecological scenery conservation area of Seoul in 2007. But Mt. Inwang is in high danger by the spread of invasive alien plants and ecosystem disturbed plants, due to artificial factors such as development pressure and the occurrence of byway trail. Therefore, Mt. Inwang needs systematic management of invasive alien plants and monitoring of long-term changes.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.18 no.6
• /
• pp.1-13
• /
• 2015

This study was conducted to develop an environmental index for assessing the vulnerability of areas with invasive alien plants. To that end, "Regional Vulnerability Numerical Index" (RVNI) was developed with a spatial statistical technique and applied to Seoul and Gyeonggi-do area first. The results are as follows. First, RVNI was high in stream areas. Second, RVNI was lowest in mountain areas. It indicates that stream areas are vulnerable to invasive alien plants. In terms of regions, Guri City is most vulnerable and Gapyeong-gun is the least vulnerable. To expand and manage the invasive alien plants, a control protocol should be developed by considering the physiology and ecology by invasive alien plant. Also, related policies should be pursued based on the results. Thus, the findings of this study can be used as baseline data for setting policies for invasive alien species management.

• Korean Journal of Ecology and Environment
• /
• v.52 no.2
• /
• pp.161-170
• /
• 2019

Invasive alien plants were identified and recorded in Ulsan city based on field surveys and related literatures. These plants consisted of 147 taxa in total, belonging to 30 families, 93 genera, 144 species, 2 subspecies and 1 variant. The family of Asteraceae was predominant with 42 taxa, followed by Gramineae with 27 taxa and Leguminosae with 15 taxa. According to the result of life-form based distribution analysis revealed that 62 taxa (42.2%) were annual plants, 48 taxa (33.6%) were perennial plants, 34 taxa (23.1%) were biennial plants, and 3 taxa (2%) were woody perennials. Compare to other administrative districts in Korea, prevalence of invasive alien plants in a certain city of Ulsan showed the seventh highest species number followed after Jeju, Gyeonggi, Jeonnam, Incheon, Seoul and Gangwon. On the basis of the results from the country origin analysis, two dominating taxa were introduced from Europe and America, 55 taxa and 51 taxa respectively. The spreading grade of alien plants was elucidated in order of 1 grade (PS) 67 grade (21.1%)>2 grade (MS) 31 taxa (21.1%)>5 grade (WS) 18 taxa (11.6%)>3 grade (CS) 17 taxa (11.6%)>4 grade (SS) 14 taxa (9.5%). Ulsan city is one of a pivotal conduit for the introduction of invasive alien plants. Thereby, reliable management plans are required to monitor these species.

• Korean Journal of Ecology and Environment
• /
• v.54 no.4
• /
• pp.327-333
• /
• 2021

The two main hypotheses that explain why invasive alien plants successfully colonize new environments are: 1) invasive alien plants are functionally different from native plants in a community, and 2) the plants can adapt well to new environments because they are functionally similar to native plants. The present study investigated the functional traits of naturalized alien herbaceous plants and their native neighbors in a riparian park area near the Hapcheon-Changyeong weir along the Nakdong River to determine which of the two hypotheses applied to the study area. According to the results, leaf functional traits, such as leaf area, specific leaf area, leaf thickness, leaf dry matter content, leaf nitrogen content, and leaf carbon content differed between naturalized alien and native plants, which could be attributed to the higher leaf nitrogen contents in naturalized alien plants than in native plants. The high leaf nitrogen contents are associated with high photosynthetic rates, which lead to effective resource use and rapid growth; therefore, naturalized alien plants growing in the study area were considered to have such functional traits. The results of the present study support the hypothesis that the successful establishment of invasive alien plants is attributed to the functional trait differences between invasive and native plants.

• Korean Journal of Plant Resources
• /
• v.34 no.3
• /
• pp.223-248
• /
• 2021

We conducted a taxonomic study and agricultural environmental risk assessments of 41 putative invasive alien plants designated by the Ministry of Environment in 2016. In order to achieve the goal, we carried out the field survey four times including the United States, Australia, and Mexico, and investigated specimens, literature, and other information including seed morphology, classification key, and habitat conditions. In this study, we reported the taxonomic characters, ecological risk, and weed risk assessment of 41 putative invasive alien plants, and suggested significant information about 11 species to contribute to establish solutions of regulation management for putative invasive alien plants - Spirodela punctata (G.Mey.) C.H.Thomps. (Araceae), Sagittaria graminea Michx. (Alismataceae), Elodea nuttallii (Planch.) H.St. John, Hydrocharis morsus-ranae L., Stratiotes aloides L. (Hydrocharitaceae), Eichhornia azurea (Swartz) Kunth, Monochoria hastata (L.) Solms (Pontederiaceae), Aegilops tauschii Coss. (Poaceae), Myriophyllum heterophyllum Michx. (Haloragaceae), Bunias orientalis L. (Brassicaceae), and Heracleum sosnowskyi Manden. (Apiaceae).

• Korean Journal of Ecology and Environment
• /
• v.54 no.2
• /
• pp.142-150
• /
• 2021

To analyze the distribution characteristics of alien plants in various habitat types, 249 sites were selected from four administrative districts in the Gyeongsang region of Korea. The survey was conducted across nine different habitat types. A total of 115 species of alien plants were collected; comprising 23 families, 73 genera, 112 species, and 3 varieties. Species from the family Compositae were the most common at 33.0%. Raunkiaer's life forms had the highest occurrence rate with 70 species(60.9%) of therophytes(Th) followed by 30 species (26.1%) of hemicryptophytes (H) and 8 species (7.0%) of geophytes (G). The distributions of alien plant species per habitat type were: 81 species on the roadside; 80 species on vacant lots and artificial habitats; 67 species in streams; 53 species in grasslands; 47 species in cultivated lands; and 39 species on the coast. Since 2017, the number of alien plants has increased in Gyeongju-si, Cheongdo-gun, and Pohang-si, and decreased in Ulsan Metropolitan-si. In each region, 614 taxa were observed. The invasive alien species, Sicyos angulatus, Hypocaeris radicata, and Solanum carolinense, were observed for the first time and are expected to further increase the disturbance of the ecosystem.

• Korean Journal of Plant Resources
• /
• v.34 no.6
• /
• pp.616-632
• /
• 2021

We performed taxonomic reviews and habitat circumstances survey for 41 un-introduced environmentally harmful plants (as designated by the Ministry of Environment, Korea in 2016). And we investigated plant specimens from several herbaria and performed a field survey in the southeastern region of the United States. Based on the result, we presented the most comprehensive results of weed risk evaluation and taxonomic description up to now as well as classification keys for 11 species to apply the regulation management of putative invasive alien species - Senecio madagascariensis Poir., Sphagneticola trilobata (L.) Pruski, Ageratina riparia (Regel) R.M. King & H. Rob. (Asteraceae), Andropogon gayanus Kunth (Poaceae), Echinocystis lobata (Michx.) Torr. & A. Gray (Cucurbitaceae), Salvinia minima Baker (Salviniaceae), Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae), Asparagus asparagoides (L.) Druce (Asparagaceae), Alternanthera pungens Kunth (Amaranthaceae), Salpichroa origanifolia (Lam.) Thell., and Lycium ferocissimum Miers (Solanaceae).