Contemporary remotely sensed data products refine invasive plants risk mapping in data poor regions

Invasive weeds are a serious problem worldwide, threatening biodiversity and damaging economies. Modeling potential distributions of invasive weeds can prioritize locations for monitoring and control efforts, increasing management efficiency. Forecasts of invasion risk at regional to continental scales are enabled by readily available downscaled climate surfaces together with an increasing number of digitized and georeferenced species occurrence records and species distribution modeling techniques. However, predictions at a finer scale and in landscapes with less topographic variation may require predictors that capture biotic processes and local abiotic conditions. Contemporary remote sensing (RS) data can enhance predictions by providing a range of spatial environmental data products at fine scale beyond climatic variables only. In this study, we used the Global Biodiversity Information Facility (GBIF) and empirical maximum entropy (MaxEnt) models to model the potential distributions of 14 invasive plant species across Southeast Asia (SEA), selected from regional and Vietnam’s lists of priority weeds. Spatial environmental variables used to map invasion risk included bioclimatic layers and recent representations of global land cover, vegetation productivity (GPP), and soil properties developed from Earth observation data. Results showed that combining climate and RS data reduced predicted areas of suitable habitat compared with models using climate or RS data only, with no loss in model accuracy. However, contributions of RS variables were relatively limited, in part due to uncertainties in the land cover data. We strongly encourage greater adoption of quantitative remotely sensed estimates of ecosystem structure and function for habitat suitability modeling. Through comprehensive maps of overall predicted area and diversity of invasive species, we found that among lifeforms (herb, shrub, and vine), shrub species have higher potential invasion risk in SEA. Native invasive species, which are often overlooked in weed risk assessment, may be as serious a problem as non-native invasive species. Awareness of invasive weeds and their environmental impacts is still nascent in SEA and information is scarce. Freely available global spatial datasets, not least those provided by Earth observation programs, and the results of studies such as this one provide critical information that enables strategic management of environmental threats such as invasive species

Influence of institutional arrangements on invasive plant species management from multilevel perspectives: A case study in Vietnam’s National Parks

Invasive plant species (IPS) management in national parks is a complex problem often characterised by the involvement of various organisations with different responsibilities, legal mandates, and jurisdictions. These institutional arrangements shape the structure, function, and decision-making behaviours of organisations and influence management effectiveness. Drawing on institutional theory, this study analysed institutional arrangements and how these influenced IPS management in national parks of Vietnam. Data were collected between May and July 2017 using in-depth interviews with 39 key informants with responsibilities for IPS management at different institutional levels (national, provincial, local national parks). Results demonstrated that IPS management in Vietnam’s national parks was characterised by centralised management with overlaps and gaps in vertical institutional relationships that limited the effectiveness of horizontal relationships. These characteristics resulted in a lack of clear guiding regulations and limited resources that restricted decision making and hindered implementation at the local national park level. The study highlights the need for a common set of principles across agencies, governed by an overarching body to promote constructive relationships across the vertical and horizontal institutional dimensions of IPS management

Impact of a native invasive weed (Microstegium ciliatum) on regeneration of a tropical forest

Infestations of invasive plants can hinder forest regeneration in biodiversity hotspots in tropical Asia. Microstegium ciliatum is a native grass in parts of tropical and subtropical Asia. To assess impacts of Microstegium on secondary forest succession in its native range, a field experiment was undertaken in abandoned agricultural settlements in Cuc Phuong National Park, Vietnam from 2016 to 2018. Plots were established across 6 sites under low, medium and high tree canopy levels. In manipulated plots, M. ciliatum was killed with a grass-specific herbicide and invading vines were cut in a subset of plots; control plots were untreated. The results show that in its native range Microstegium can be invasive with impacts on forest restoration. Application of herbicide reduced the cover of M. ciliatum from 85 to 3% and increased the diversity and number of tree seedlings within the 2 years of the experiment. There was no difference in tree seedling abundance between the herbicide and herbicide + vine cutting treatments, but the number of tree seedling species was significantly higher in the latter in the 2nd year after treatments were applied under the medium canopy. The overstory influenced forest regeneration in the manipulated plots as there was a greater number of tree seedlings and species in plots under medium and high-density canopies. The results suggest that management of the native invasive grass under tree canopies will facilitate forest restoration after disturbance from agriculture and lead to the early recruitment of mid and late successional forest species

Unexpected synthesis and crystal structure of N-{2-[2-(2-acetylethenyl)phenoxy]ethyl}-N-ethenyl-4-methylbenzenesulfonamide

The title compound, C21H23NO4S, obtained by alkaline treatment of 1,5-bis(1-phenoxy)-3-azapentane at moderate heating, is a N-tosylated secondary vinylamine. An intramolecular S=O⋯H - C hydrogen bond generates a 13-membered ring. The benzalacetone moiety adopts a trans conformation with respect to the C=C double bond, which is slightly longer than usual due to the conjugation with a neighbouring acetyl group. Theoretical predictions of potential biological activities were performed, suggesting that the title compound can inhibit gluconate 2-dehydrogenase (85% probability), as well as to act as a mucomembranous protector (73%). © 2020