DOI: 10.5061/dryad.1ns1rn964
title: Forest management and the colonization of artificial tree holes by aquatic insect larvae

description: Human activities in forests lead to alteration or even destruction of
 habitats for numerous organisms, often resulting in a decline of
 biodiversity. Insects inhabiting water-filled tree holes may be especially
 sensitive to human impact as they require these microhabitats for at least
 part of their life cycle, with larvae mainly feeding on plant and animal
 debris accumulating in the water, until they actively disperse in their
 adult stage. The processes leading to successful colonization of these
 microhabitats are not well understood, and it is unclear how forest
 management could influence them. We used sequential collection and
 recording of larval communities in artificial tree-hole analogues to study
 the process of colonization by aquatic tree-hole insects. We focused on
 the effects of parameters related to forest management as well as
 microhabitat properties on abundance, species richness and community
 composition during colonization of artificial tree holes by aquatic
 tree-hole insects. We observed complex, and partly species-specific,
 temporal patterns of colonization of these new microhabitats. We found
 that the forest management intensity index ForMI, tree composition of
 forests as well as distance to natural water-filled tree holes and debris
 type were important in shaping community composition of insect larvae
 inhabiting tree holes across the entire colonization process. Larval
 abundance was negatively affected by increased distance to natural
 microhabitats and by changes in microclimate. Our results suggest that
 forest management significantly impacts microhabitat colonization dynamics
 of tree-hole insects, emphasizing the need for less-intensively managed
 forests to support natural tree-hole communities. We recommend the
 protection, creation and maintenance of tree-related microhabitats, for
 example through promotion of habitat trees in managed forests, to sustain
 higher abundances of tree-hole inhabitants. Our findings underline the
 ecological value of water-filled tree holes and support their integration
 into forest conservation strategies as both essential habitats and
 valuable indicators of environmental change.
description: # Forest management and the colonization of artificial tree holes by
 aquatic insect larvae Dataset DOI:
 [10.5061/dryad.1ns1rn964](10.5061/dryad.1ns1rn964) ## Description of the
 data and file structure ### Files and variables #### File:
 Bartel_et_al_EcolEvo25_data_for_dryad.csv **Description:** * Study years:
 2015, 2016 * Study location:Biodiversity Exploratories
 ([http://www.biodiversity-exploratories.de](http://www.biodiversity-exploratories.de)), regions (Schwaebische) Alb, Hainich(-Duen), Germany, Schorfheide-Chorin * (Schwaebische) Alb: 4834-4853N; 918-960E, Hainich(-Duen): 5094-5138N; 1017-1078E, Schorfheide-Chorin: 52515311N, 13361401E * Missing Value Indicator: NA ##### Variables * Plot:Plot ID * Container: Number of the container on the tree, filled with beech or conifer debris (Beech_1-5, Conifer_1-5) * Region: Region tree hole was sampled (AEW= Schwaebische Alb, HEW=Hainich-Duen, SEW=Schorfheide-Chorin) * Debris: Type of debris (beech leaves, spruce or pine needles) filled in the container * Period: Time period of sampling (1-5); periods 1-4: May, June, July, August 2015, period 5: June 2016 * ForMI: Forest management intensity index (following Kahl, T., Bauhus, J., 2014) * Iharv: Proportion of harvested biomass * Inonat: Proportion of non-native tree species * Idwcut: Proportion of dead wood with saw cuts * Dom_tree: Dominate tree species in the plot (Beech, Pine, Spruce) * Management: Management of forests (managed/unmanaged) * Date_Setup: Date of setup (Day.Month.Year) * Date_removed: Date of sampling (Day.Month.Year) * DBH: Diameter at breast height (in cm) of tree which the artificial tree holee was attached to * Direction: Cardinal direction of the container on the tree * Water_volume: Measured volume of the water (in ml) at time of sampling * distance_nat_hole: Distance to the nearest natural tree hole in the plot (m) * distance_hole: ID of nearest natrual tree hole in the plot  * distance_between: Distance between the two trees (Beech/Conifer) in the plot  (m) * Initial_DO: Oxygen content of water (in mg/l) at time of setup * Initial_pH: pH of the water at time of setup * Initial_DO.t: Water temperature (C) at time of setup * Collection_DO: Oxygen content in the water (in mg/l) at time of sampling * Collection_pH: pH of the water at time of sampling * Collection_Temp1: Water temperature (C) at time of sampling * Prio_ser: Total number of *Prionocyphon serricornis* larvae in container * Met_cav: Total number of *Metriocnemus cavicula* larvae in container * Myia_flo: Total number of *Myiatropa florea* larvae in container * Dasy_1: Total number of *Dasyhelea* sp.1 larvae larvae in container * Cera_unk2: Total number of *Mycetobia obscura* (Anisopodidae) larvae in container * Cera_unk3+4: Total number of *Silvicola cinctus* (Anisopodidae) larvae in container * Atri_sp: Total number of *Atrichopogon* sp.1 larvae in container * Chironomus_sp1: Total number of *Chironomus* sp.1 larvae in container * Chiro_unk1: Total number of Chironomidae sp.1 larvae in container * Aed_gen: Total number of *Aedes geniculatus* larvae in container * Ano_plum: Total number of *Anonpheles plumbeus* larvae in container * Phaonia_sp: Total number of *Phaonia* sp.1 larvae in container * Peri_sp: Total number of *Pericoma* sp.1 larvae in container * Psych_sp3: Total number of Psychodidae sp. 3 larvae in container * Psych_sp5: Total number of Psychodidae sp. 3 larvae in container * Psych_sp6: Total number of Psychoda sp. (Psychodidae) larvae in container * Syrph_unk1: Total number of Syrphidae sp.1 larvae in container * Dolich_sp1: Total number of Dolichopodidae sp.1 in container * Tabanidae_unk1: Total number of Tabanidae sp.1 in container * Tabanidae_unk2: Total number of *Phaonia subventa* (Muscidae) larvae in container * Tipul_sp3: Total number of Tipulidae sp.3 in container * Tipul_sp5: Total number of Tipulidae sp.5 in container * Stratiomyidae: Total number of Stratiomyidae sp.1 in container * Platypezidae: Total number of Platypezididae sp.1 in container * Megselia_sp: Total number of *Megaselia* sp.1 larvae in container * Dipunk1: Total number of unknown Diptera 1larvae in container * Dip_unk_4: Total number of unknown Diptera 4 larvae in container * Dip_unk_5: Total number of Cecidomyidae sp.1 Diptera larvae in container * Dip_unk_9: Total number of unknown Diptera larvae 9 in container * Dip_unk_10: Total number of Cecidomyidae sp.2 Diptera larvae in container * Dip_unk_11: Total number of unknown Diptera 11 larvae in container * Dip_unk_13: Total number of unknown Diptera larvae 13 in container * Dip_unk_15: Total number of unknown Diptera larvae 15 in container * Dip_unk_17: Total number of unknown Diptera larvae 17 in container * Callicera: Total number of *Callicera* sp.1 larvae in container * Dip_unk_20: Total number of Dolichopodidae sp.2 in container * Dip_unk_21: Total number of unknown Diptera larvae 21 in container * Dip_unk_22: Total number of Cecidomyidae sp.3 larvae in container * Dip_unk_26: Total number Fagisyrphus cinctus/Meliscaeva auricollis in container * Dip_unk_31: Total number of unknown Diptera 31 larvae in container * Dip_unk_32: Total number of Cecidomyidae sp.4 Diptera larvae in container * Syrp_unk_19: Total number of Syrphidae sp.1 larvae in container * unidentified_dip: Total number of unidentified Diptera larvae (excluded from statistics) * Species_rich: Species richness of of larvae in contaier * Abundance: Total abundance of larvae in contaier * Tree: Number of tree (1-72) ## Access information Other publicly accessible locations of the data: * 
 
 Data was derived from the following sources: *