DOI: 10.5061/dryad.s4mw6m9fh
title: Microplastics promote the invasiveness of invasive alien species under fluctuating water regime

description: Microplastic pollution and alien plant invasions are two important threats
 to terrestrial ecosystems. Microplastics (MPs) alter the physical and
 chemical characteristics of soil,  potentially affecting the
 performance of alien plants. However, previous studies have overlooked the
 impact of weather on invasive plants in areas polluted by MPs. With the
 global increase in extreme rainfall events, it is imperative to redefine
 the correlation between MPs and invasive plants. Here, we conducted an
 experiment in a climate chamber to examine the effects of MPs on the
 growth and development of both native and invasive alien plants under a
 constant and fluctuating water regime (FWR). The FWR simulated extreme
 water pulses during the 2016-2020 growing seasons in Wuhan, China. Our
 results indicated that biomass accumulation and roots development were
 influenced by water conditions and MPs pollution in both invasive and
 native species. The extent of the effects varied between the two groups of
 plant species. FWR promoted plant growth and fine root development in
 invasive plants but reduced the maximum quantum efficiency of photosystem
 II (Fv/Fm) and nonphotochemical quenching (NPQ) indices of native plants.
 Moreover, FWR attenuated the negative effects of polybutylene succinate
 (PBS, degradable MPs) on biomass and root characteristics (length, surface
 area, and tips). FWR compensates for the negative impacts of MPs on the
 total and belowground biomass of the invasive species Paspalum
 dilatatum and Sphagneticola trilobata, but not on the native
 species. Consequently, invasive species showed better performance than
 native species in the fine-root development of biomass growth and
 chlorophyll fluorescence under the combined effects of MPs and FWR.
 Synthesis and Applications. Our findings suggest that MPs pollution
 enhances the competitiveness of invasive alien species over the native
 species when exposed to pronounced dry-wet water cycle conditions,
 potentially affecting the composition and biodiversity of the ecosystems.
 Thus, controlling MPs pollution should be a part of the management
 strategy to conserve biodiversity and ecosystems.
description: # Microplastics and invasive species under fluctuating water regime: Open
 Source Data We have submitted our raw data of native or invasive plant
 biomass (**Biomass_MP.csv**), fine roots of native or invasive plants
 (**Fineroot_MP.csv**), chlorophyll fluorescence of native or invasive
 plants (**Fluorescence_MP.csv**), and R script (**MP_Code.R**). ##
 Descriptions ### **Biomass\_MP** * *origin*: Native or alien invasive
 plants * *water*: A treatment for watering plants, including constant and
 fluctuant water * *MP*: Microplastics treatment, including microplastics
 with and microplastics without * *MP_type*: The type of microplastics *
 Dg_PBS = degradable microplastics polybutylene succinate (PBS) * unDg_PP =
 nondegradable microplastics polypropylene (PP) * blank_control =
 microplastics without * *size*: The size of microplastics (small or large
 and ck) * *spp*: Species abbreviation * *species*/*genus*/*family*:
 Species, Genus and Family of plants * *replicates*: Serial number of
 species in the same processing * *biomass*: Total mass of native or alien
 invasive plants (total mass) (g) * *biomass_root*: Belowground mass of
 native or alien invasive plants (root mass) (g) * *biomass_ground*:
 Aboveground mass of native or alien invasive plants (shoot mass) (g) ###
 **Fineroot\_MP** * *origin*: *replicates* : same to file
 "Biomass_MP" * *L*: Fine roots (Diameter ≤ 0.25 mm) length of
 native or alien invasive plants (cm) * *SA*: Fine roots (Diameter ≤ 0.25
 mm) surface area of native or alien invasive plants (cm^2) * *L_T*: Total
 roots (all roots) length of native or alien invasive plants (cm) * *SA_T*:
 Total roots (all roots) surface area of native or alien invasive plants
 (cm^2) * *T_T*: The number of total roots (all roots) tips in native or
 alien invasive plants ### **Fluorescence\_MP** * *origin*: *replicates* :
 same to file "Biomass_MP" * *FvFm*: Fv/Fm (photochemical
 efficiency of PSⅡin the light), the ratio of Fv (variable fluorescence)
 and Fm (fluorescence maximum) of native or alien invasive plants; FvFm is
 optimal/maximal photochemical efficiency of PSⅡin the dark, reflecting the
 intrinsic light energy conversion efficiency of PSⅡ reaction center *
 *NPQ*: NPQ of native or alien invasive plants; NPQ is one of the major
 photoprotective mechanisms that protects itself by regulating, for
 example, the dissipation of excess light energy as heat. All
 "NA" in our files are missing data.