DOI: 10.5061/dryad.h44j0zpw4
title: Data from: Cross-boundary connections of biodiversity and ecosystem functioning in boreal ecosystems

description: Relationships between biodiversity and ecosystem functioning (BEF) are
 typically investigated separately in different ecosystem types, often
 neglecting connections across ecosystem boundaries. Here, we examined the
 cross-boundary relationships between terrestrial and aquatic biodiversity
 and terrestrial and aquatic ecosystem function (here productivity in terms
 of biomass). We collected a dataset from 100 Finnish boreal lakes for
 phytoplankton and zooplankton, and for trees and understory plants in the
 surrounding forest ecosystems. We explored the connections among climatic,
 catchment, and local environmental factors, and terrestrial and aquatic
 biodiversity and productivity using structural equation modeling (SEM).
 The results indicated cross-boundary connections between the two realms.
 Terrestrial biodiversity was associated with terrestrial productivity and
 connected to lake water chemistry directly and indirectly through
 terrestrial productivity. Water chemistry in turn was linked to aquatic
 biodiversity and productivity. Within both realms, biodiversity was
 positively associated with ecosystem productivity. The effects of
 biodiversity per se were weaker in the aquatic realm, in which nutrient
 availability was the strongest determinant of productivity. Our findings
 underscore the importance of exploring cross-ecosystem coupling, as the
 impacts of several global change drivers, such as climate and land-use
 change or eutrophication extend beyond individual realms to transcend
 ecosystem boundaries. In particular, the combined effects of warming,
 eutrophication, and increasing terrestrial productivity are likely to
 increase the import of allochthonous nutrients to boreal lake ecosystems,
 resulting in enhanced primary productivity therein. As freshwater
 ecosystems integrate the effects of direct and indirect changes in their
 catchments, they serve as ideal settings for investigating cross-ecosystem
 coupling and act as valuable sentinels of climate and other global
 changes.
description: # Data from: Cross-boundary connections of biodiversity and ecosystem
 functioning in boreal ecosystems
 [https://doi.org/10.5061/dryad.h44j0zpw4](https://doi.org/10.5061/dryad.h44j0zpw4) ## Description of the data and file structure Data from: Cross-boundary connections of biodiversity and ecosystem functioning in boreal ecosystems ### Files and variables The dataset consists of the following five files: TER_AQU_data1.xlsx (Data 1) TER_AQU_data2.xlsx (Data 2) TER_AQU_data3.xlsx (Data 3) TER_AQU_data4.xlsx (Data 4) TER_AQU_data5.xlsx (Data 5) **Description:** Data are compiled in 5 Excel files: **1) Data 1 metadata** | Column | Entry | Unit | Explanation | | :----- | :----------- | :------ | :----------------------------------------------------------- | | A | lakeID | | ID for each lake | | B | latitude | ° | Latitude | | C | longitude | ° | Longitude | | D | conductivity | μS/cm | Water conductivity | | E | pH | | Water pH | | F | water\_temp | °C | Water temperature | | G | water\_depth | m | Water depth | | H | solubleP | µg/l | Soluble phosphorus | | I | TP | µg/l | Total phosphorus | | J | TN | mg/l | Total nitrogen | | K | chla | µg/l | Chlorophyll a | | L | colour | mg Pt/l | Water colour | | M | lake\_area | ha | Lake area | | N | clearcut | % | Catchment clear cut areas and tree regeneration (0–20 years) | | O | artificial | % | Catchment artificial surfaces | | P | agriculture | % | Catchment agricultural areas | | Q | forest | % | Catchment forests and semi-natural areas (20+ years) | | R | wetland | % | Catchment wetlands | | S | water | % | Catchment waterbodies | | T | NDVI | | Normalized difference vegetation index | | U | tavg | °C | Average daily mean temperature | | V | GDD | | Growing degree days | | W | region | | Sampling region (1 to 5) | **2) Data 2 metadata** | Column | Entry | Explanation | | :-------- | :----------------------- | :----------------------------------------- | | A | lakeID | ID for each lake | | B onwards | Phytoplankton taxa names | Relative abundances for phytoplankton taxa | **3) Data 3 metadata** | Column | Entry | Explanation | | :-------- | :--------------------- | :--------------------------------------- | | A | lakeID | ID for each lake | | B onwards | Zooplankton taxa names | Relative abundances for zooplankton taxa | **4) Data 4 metadata** | Column | Entry | Explanation | | :----- | :----------------- | :---------------------------------------------- | | A | lakeID | ID for each lake | | B | Spruce | Relative abundances for spruce | | C | Pine | Relative abundances for pine | | D | Birch | Relative abundances for birch | | E | Other\_broadleaved | Relative abundances for other broadleaved trees | **5) Data 5 metadata** | Column | Entry | Explanation | | :-------- | :-------------------------- | :-------------------------------------------- | | A | lakeID | ID for each lake | | B onwards | Understory plant taxa names | Relative abundances for understory plant taxa |