How land-use intensity affects sexual and parthenogenetic oribatid mites in temperate forests and grasslands in Germany

AbstractIntensive land use has been shown to alter the composition and functioning of soil communities. Due to their low dispersal ability, oribatid mites are particularly vulnerable to land-use intensification and species which are not adjusted to management-related disturbances become less abundant. We investigated how different land-use parameters in forests and grasslands affect oribatid mite diversity and abundance, with a focus on: (1) species-level impacts, by classifying species as increasing (‘winners’) or decreasing (‘losers’) in abundance with higher land-use intensity, and (2) reproductive impact, by investigating whether sexual and parthenogenetic species react differently. We collected 32,542 adult oribatid mites in 60 forests and grasslands of known land-use intensity in two regions of Germany. Diversity and total abundance as well as the proportion of sexual species were higher in forests than in grasslands. Diversity declined with higher land-use intensity in forests, but increased with higher mowing and fertilization in grasslands. Depending on land-use parameter and region, abundance either declined or remained unaffected by increasing intensity. Gravidity was higher in sexual than in parthenogenetic species and sexuals had 1.6× more eggs per gravid female. Proportions of sexual species and gravid females decreased with land-use intensity in forests, but increased with mowing in grasslands. At the species level, 75% of sexuals and 87.5% of parthenogens were ‘losers’ of higher percentages of dead wood originating from management-related disturbances. Across land-use parameters and habitats, a similar proportion of sexual and parthenogenetic oribatid mite species were ‘losers’ of high land-use intensity. However, ‘winner’ species were more common among sexuals.

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Variation in Community-Level Trophic Niches of Soil Microarthropods With Conversion of Tropical Rainforest Into Plantation Systems as Indicated by Stable Isotopes (15N, 13C)

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.592149 ◽

2021 ◽

Vol 9 ◽

Author(s):

Alena Krause ◽

Dorothee Sandmann ◽

Anton Potapov ◽

Sergey Ermilov ◽

Rahayu Widyastuti ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Oil Palm ◽

Oribatid Mite ◽

Mite Species ◽

Trophic Niche ◽

Oribatid Mites ◽

Community Level ◽

Trophic Niches ◽

Oribatid Mite Species

Land-use change is threatening biodiversity worldwide and is predicted to increase in the next decades, especially in tropical regions. Most studies focused on the response of single or few species to land-use change, only few investigated the response of entire communities. In particular the response of belowground communities to changes in land use received little attention. Oribatid mites (Oribatida, Acari) are among the most abundant soil animals, involved in decomposition processes and nutrient cycling. Oribatid mite species span a wide range of trophic niches and are known to sensitively respond to changes in land use. Here, we investigated shifts in the community-level trophic niche of oribatid mites with the conversion of rainforest into rubber and oil palm plantations. Due to a wider range of resources in more natural ecosystems, we expected the community-level trophic niche to shrink with conversion of rainforest into plantations. As the conversion of rainforest into plantations is associated with reduced availability of litter resources, we expected the average trophic level (indicated by the 15N/14N ratio) to be higher and basal resources (indicated by the 13C/12C ratio) to shift toward living plant material in rubber and oil palm plantations. Our analysis showed that community-level trophic niches in rainforest and rubber agroforest (“jungle rubber”) were separated from those in monoculture plantation systems, indicating a trophic niche shift with land-use intensification. As hypothesized, oribatid mites shifted their diet toward predation and/or scavenging and toward the plant-based energy channel with transformation of rainforest into plantations. Exceptionally low minimum 13C/12C ratios in rubber plantations suggest that certain oribatid mite species in this land-use system use resources not available in the other studied ecosystems. We detected high isotopic uniqueness in oil palm plantations suggesting a low trophic redundancy and thus high vulnerability of trophic functioning in this system in comparison to rainforest. Overall, the results suggest that the conversion of rainforest into plantations is associated with pronounced shifts in community-level trophic niches of mesofauna detritivores with potential major consequences for the functioning of the decomposer system.

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Enriching plant diversity in grasslands by large-scale experimental sward disturbance and seed addition along gradients of land-use intensity

Journal of Plant Ecology ◽

10.1093/jpe/rtw062 ◽

2016 ◽

pp. rtw062 ◽

Cited By ~ 3

Author(s):

Valentin H. Klaus ◽

Deborah Schäfer ◽

Till Kleinebecker ◽

Markus Fischer ◽

Daniel Prati ◽

...

Keyword(s):

Land Use ◽

Plant Diversity ◽

Large Scale ◽

Land Use Intensity ◽

Seed Addition

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Variation in regrowth ability in relation to land-use intensity in three common grassland herbs

Journal of Plant Ecology ◽

10.1093/jpe/rtab001 ◽

2021 ◽

Author(s):

Anna Kirschbaum ◽

Oliver Bossdorf ◽

J F Scheepens

Keyword(s):

Land Use ◽

Phenotypic Plasticity ◽

Temporal Variation ◽

Temporal Stability ◽

Common Garden ◽

Grassland Management ◽

Land Use Intensity ◽

Evolutionary Changes ◽

Biomass Removal ◽

Reproductive Biomass

Abstract Aims Plant populations in managed grasslands are subject to strong selection exerted by grazing, mowing and fertilization. Many previous studies showed that this can cause evolutionary changes in mean trait values, but little is known about the evolution of phenotypic plasticity in response to land use. In this study, we aimed to elucidate the relationships between phenotypic plasticity – specifically, regrowth ability after biomass removal – and the intensity of grassland management and levels of temporal variation therein. Methods We conducted an outdoor common garden experiment to test if plants from more intensively mown and grazed sites showed an increased ability to regrow after biomass removal. We used three common plant species from temperate European grasslands, with seed material from 58 – 68 populations along gradients of land-use intensity, ranging from extensive (only light grazing) to very intensive management (up to four cuts per year). Important findings In two out of three species, we found significant population differentiation in regrowth ability after clipping. While variation in regrowth ability was unrelated to the mean land-use intensity of populations of origin, we found a relationship with its temporal variation in P. lanceolata, where plants experiencing less variable environmental conditions over the last 11 years showed stronger regrowth in reproductive biomass after clipping. Therefore, while mean grazing and mowing intensity may not select for regrowth ability, the temporal stability of the environmental heterogeneity created by land use may have caused its evolution in some species.

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Land-use intensity determines grassland Orthoptera assemblage composition across a moisture gradient

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2021.107424 ◽

2021 ◽

Vol 315 ◽

pp. 107424

Author(s):

Florian Fumy ◽

Steffen Kämpfer ◽

Thomas Fartmann

Keyword(s):

Land Use ◽

Moisture Gradient ◽

Land Use Intensity ◽

Assemblage Composition

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Molecular Correlation between Larval, Deutonymph and Adult Stages of the Water Mite Arrenurus (Micruracarus) Novus

Life ◽

10.3390/life10070108 ◽

2020 ◽

Vol 10 (7) ◽

pp. 108

Author(s):

Pedro María Alarcón-Elbal ◽

Ricardo García-Jiménez ◽

María Luisa Peláez ◽

Jose Luis Horreo ◽

Antonio G. Valdecasas

Keyword(s):

Culex Pipiens ◽

Adult Stage ◽

Gravid Female ◽

Morphological Characters ◽

Species Level ◽

Life Stages ◽

Water Mite ◽

Molecular Correlation ◽

The Common ◽

Morphological Transformations

The systematics of many groups of organisms has been based on the adult stage. Morphological transformations that occur during development from the embryonic to the adult stage make it difficult (or impossible) to identify a juvenile (larval) stage in some species. Hydrachnidia (Acari, Actinotrichida, which inhabit mainly continental waters) are characterized by three main active stages—larval, deutonymph and adult—with intermediate dormant stages. Deutonymphs and adults may be identified through diagnostic morphological characters. Larvae that have not been tracked directly from a gravid female are difficult to identify to the species level. In this work, we compared the morphology of five water mite larvae and obtained the molecular sequences of that found on a pupa of the common mosquito Culex (Culex) pipiens with the sequences of 51 adults diagnosed as Arrenurus species and identified the undescribed larvae as Arrenurus (Micruracarus) novus. Further corroborating this finding, adult A. novus was found thriving in the same mosquito habitat. We established the identity of adult and deutonymph A. novus by morphology and by correlating COI and cytB sequences of the water mites at the larval, deutonymph and adult (both male and female) life stages in a particular case of ‘reverse taxonomy’. In addition, we constructed the Arrenuridae phylogeny based on mitochondrial DNA, which supports the idea that three Arrenurus subgenera are ‘natural’: Arrenurus, Megaluracarus and Micruracarus, and the somewhat arbitrary distinction of the species assigned to the subgenus Truncaturus.

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Analytical Solutions to Trade-Offs between Size of Protected Areas and Land-Use Intensity

Conservation Biology ◽

10.1111/j.1523-1739.2012.01887.x ◽

2012 ◽

Vol 26 (5) ◽

pp. 883-893 ◽

Cited By ~ 18

Author(s):

VAN BUTSIC ◽

VOLKER C. RADELOFF ◽

TOBIAS KUEMMERLE ◽

ANNA M. PIDGEON

Keyword(s):

Land Use ◽

Protected Areas ◽

Analytical Solutions ◽

Land Use Intensity ◽

Trade Offs

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Effects of habitat structure and land-use intensity on the genetic structure of the grasshopper species Chorthippus parallelus

Royal Society Open Science ◽

10.1098/rsos.140133 ◽

2014 ◽

Vol 1 (2) ◽

pp. 140133 ◽

Cited By ~ 4

Author(s):

Kerstin R. Wiesner ◽

Jan Christian Habel ◽

Martin M. Gossner ◽

Hugh D. Loxdale ◽

Günter Köhler ◽

...

Keyword(s):

Genetic Diversity ◽

Land Use ◽

Genetic Structure ◽

Sampling Site ◽

Land Use Intensity ◽

Habitat Size ◽

Grasshopper Species ◽

Chorthippus Parallelus ◽

Landscape Characteristics ◽

Local Populations

Land-use intensity (LUI) is assumed to impact the genetic structure of organisms. While effects of landscape structure on the genetics of local populations have frequently been analysed, potential effects of variation in LUI on the genetic diversity of local populations have mostly been neglected. In this study, we used six polymorphic microsatellites to analyse the genetic effects of variation in land use in the highly abundant grasshopper Chorthippus parallelus . We sampled a total of 610 individuals at 22 heterogeneous grassland sites in the Hainich-Dün region of Central Germany. For each of these grassland sites we assessed habitat size, LUI (combined index of mowing, grazing and fertilization), and the proportion of grassland adjoining the sampling site and the landscape heterogeneity (the latter two factors within a 500 m buffer zone surrounding each focal site). We found only marginal genetic differentiation among all local populations and no correlation between geographical and genetic distance. Habitat size, LUI and landscape characteristics had only weak effects on most of the parameters of genetic diversity of C. parallelus ; only expected heterozygosity and the grasshopper abundances were affected by interacting effects of LUI, habitat size and landscape characteristics. The lack of any strong relationships between LUI, abundance and the genetic structure might be due to large local populations of the species in the landscape, counteracting local differentiation and potential genetic drift effects.

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