DOI: 10.5061/dryad.573n5tbkf
title: Data from: Moss community dynamics and canopy-mediated environmental influences during primary succession in a glacier retreat zone

description: This dataset contains field and experimental data on moss community
 dynamics, biomass, cover, and physiological functions (photosynthesis and
 N₂-fixation) along a 129-year primary successional chronosequence on the
 glacial retreat area of Hailuogou Glacier, eastern Qinghai-Tibet Plateau.
 The dataset integrates: Successional surveys of moss biomass and cover
 across stages S0 to S6; Reciprocal moss transplantation experiments among
 three representative successional sites with varying canopy cover; Canopy
 tree litter addition experiments, testing effects of different litter
 types on moss function; Functional trait measurements, including
 photosynthetic rates and nitrogen fixation (via acetylene reduction
 assay), across treatments and years (2018–2019); Statistical analyses such
 as linear regression and redundancy analysis (RDA), linking environmental
 drivers (e.g., canopy cover, litter, throughfall NH₄⁺, daylight) to moss
 functional responses; Conceptual modeling to summarize interactions
 between canopy-mediated environmental factors and moss productivity. The
 data support the conclusion that moss biomass and function are tightly
 regulated by canopy structure and nutrient inputs, with notable trade-offs
 between photosynthesis and N₂-fixation across successional stages. This
 dataset provides valuable insight into moss ecological roles during
 primary succession following glacial retreat.
description: # **Data from: Moss community dynamics and canopy-mediated environmental
 influences during primary succession in a glacier retreat zone** #
 [https://doi.org/10.5061/dryad.573n5tbkf](https://doi.org/10.5061/dryad.573n5tbkf) Main file: Moss_Community_Dynamics_and_canopy-mediated_environmental_influences_during_primary_succession_in_a_Glacier_retreat_Zone.zip This dataset supports a study of moss community structure, biomass, cover, nitrogen fixation, and photosynthesis along a 129-year primary successional chronosequence in the Hailuogou Glacier foreland, eastern Qinghai-Tibet Plateau. The data were collected through long-term field surveys and manipulative experiments, including reciprocal moss transplantation and canopy litter addition. These data provide insights into how moss functions respond to environmental changes mediated by canopy development during succession after glacial retreat. --- ## Description of the Data and File Structure This dataset includes four CSV files, each corresponding to a specific component of the study. All files use commas as delimiters and contain clear column headers. All variable units are specified in the file descriptions below. ### File 1: `The influence of canopy litter addition on moss ecological functions.csv` This file contains experimental results from a canopy litter addition experiment. The experiment assessed the effects of different tree litter types (Poplar, Willow, Sea buckthorn) on moss biomass, nitrogen fixation (via acetylene reduction), and photosynthesis across two years (2018 and 2019).\ **Variables include:** * `Treatment`: Litter type (L1 = Poplar, L2 = Willow, L3 = Sea buckthorn) * `Year`: Sampling year * `Site`: Successional site where experiment was conducted * `Biomass (g/m²)`, `N2 Fixation (nmol C₂H₄ g⁻¹ h⁻¹)`, `Photosynthesis Rate (µmol CO₂ m⁻² s⁻¹)` * Replicates: n = 5 per treatment ### File 2: `The effects of moss transplantation on growth, nitrogen fixation, and photosynthesis.csv` This file includes data from the reciprocal moss transplantation experiment across three successional stages. It records changes in moss cover, biomass, nitrogen fixation, and photosynthesis after moving moss carpets between open and closed canopy sites.\ **Variables include:** * `Transplantation Direction`: E.g., S1–S2, S2–S1, etc. * `Species`: Moss species involved (Racomitrium, Eurhynchium, Cirriphyllum) * `Year`: 2018 or 2019 * `Cover (%)`, `Biomass (g/m²)`, `N2 Fixation`, `Photosynthesis Rate`\ **Note:** In this file, `"n/a"` indicates data that were not available due to experimental limitations (e.g., moss mortality, failed measurement attempts, or environmental conditions). These values represent missing—not zero or inapplicable—data. ### File 3: `Regression and RDA of Environmental Effects on Moss Function.csv` This file includes data used for statistical analyses—linear regression and redundancy analysis (RDA)—linking moss functions with environmental factors such as canopy litter biomass, daylight hours, temperature, and throughfall ammonium (TF-NH₄⁺).\ **Variables include:** * `Site`, `Successional Stage`, `Biomass`, `Cover`, `N2 Fixation`, `Photosynthesis Rate` * `Daylight Hours`, `Temperature`, `TF-NH₄⁺ (mg/L)`, `Litter Biomass (g/m²)`\ **Note:** In this file, `"n/a"` is used to indicate data that could not be obtained due to field constraints or instrument failure. These missing values are explained in the README to prevent misinterpretation. ### File 4: `Dynamics of moss cover and biomass along the successional chronosequence.csv` This file presents field data of moss biomass and cover at sites S0 to S6 across a 129-year chronosequence.\ **Variables include:** * `Site`, `Successional Age (years)` * `Moss Cover (%)`, `Moss Biomass (g/m²)` * `Replicate ID`, `Mean`, `Standard Error` * Significant groupings from ANOVA are included via letter codes (a, b, c) for post-hoc comparisons.