DOI: 10.5061/dryad.3xsj3txtd
title: Linking leaf economic traits with forage quality across temperate grasslands under ambient and drought conditions

description: Intensifying droughts may disrupt grassland services, including the forage
 provision for herbivores. However, less is known about drought impacts on
 forage quality. While previous studies have shown that leaf economic
 traits reflect drought effects on plant communities, whether leaf traits
 can predict forage quality pattern under drought remains unclear. So, we
 simulated early- and late-season droughts in three grasslands in the Swiss
 Jura Mountains over two growing seasons. Early-season drought involved a
 70% reduction in ambient precipitation during the first two-month growth
 cycle of a six-month growing season, while late-season drought reduced
 same precipitation during the second two-month growth cycle. We collected
 data on forage quality parameters (protein, minerals, water-soluble
 carbohydrates, neutral detergent fibre, and acid detergent fibre) and leaf
 traits [community-weighted mean (CWM) specific leaf area (SLA) and leaf
 dry matter content (LDMC)]. We used these data to address three questions:
 (1) how do forage quality parameters and leaf economic traits
 [community-weighted (cwm) SLA and LDMC] changed from early to late periods
 of the season under ambient conditions; (2) how do forage quality
 parameters and leaf traits respond to early- and late-season droughts; and
 (3) how do community-weighted leaf traits and forage quality parameters
 relate under early- and late-season ambient and drought conditions.
description: # Linking leaf economic traits with forage quality across temperate
 grasslands under ambient and drought conditions Dataset DOI:
 [10.5061/dryad.3xsj3txtd](10.5061/dryad.3xsj3txtd) ## Description of the
 data and file structure **Study Overview** This study examined how early-
 and late-season extreme droughts affect forage quality and
 community-weighted leaf traits across three grassland sites in the Swiss
 Jura Mountains—Chéserex (Site A; N 46°24’, E 6°10’), Saint-George (Site B;
 N 46°30’, E 6°15’), and Trois Chalets (Site C; N 46°53’, E 6°21’)—during
 the 2015 and 2016 growing seasons. **Experimental Design** *
 **Treatments**: * Control (normal precipitation all season) * Early-season
 drought (first 2 months of growing season) * Late-season drought (next 2
 months) * **Plot Setup**: * Each of the three sites had 5 blocks (12 m × 6
 m each) * Each block contained 3 plots (4 m × 0.9 m each), one per
 treatment, spaced 80 cm apart **Rainout Shelter System** * All plots
 (control and drought) were covered by transparent rainout shelters (12 m ×
 6.4 m × 3 m), transmitting over 90% of photosynthetically active
 radiation. * Water was added manually using metered sprinkler bars. *
 *Control plots*: received site-specific 30-year average monthly
 precipitation (11 rainy days/month) * *Drought plots*: received 30% of
 control water during their designated drought period, applied at reduced
 frequency (4–5 day intervals) * *Non-drought periods*: drought plots
 received the same watering as the control **Watering Schedule (based on
 historical data)** * Early-season precipitation (mm): * Site A: 143 * Site
 B: 234 * Site C: 240 * Late-season precipitation (mm): * Site A: 154 *
 Site B: 213 * Site C: 272 **Measured Variables** * **Forage quality**: *
 *Readily digestible cell constituents*: protein, ash, water-soluble
 carbohydrates (WSC, g/kg) * *Cell wall components*: neutral detergent
 fibre (NDF, g/kg), acid detergent fibre (ADF, g/kg) * **Community-weighted
 leaf traits**: specific leaf area (cwmSLA, cm2/g), leaf dry matter content
 (cwmLDMC, mg/g) ### Files and variables #### File:
 Trait_ForageQuality_Muraina_et_al.csv **Description:**  ##### Variables *
 Year: Numeric identity of the year the experiment was conducted (i.e.,
 2015 or 2016) * Yr: Categorial identity of the year the experiment was
 conducted * Time: The period of the season during which the data were
 collected   * Site: Location of each experimental site; Chéserex (CH; N
 46°24’, E 6°10’), Saint-George (SG; N 46°30’, E 6°15’), and Trois Chalets
 (TC; N 46°53’, E 6°21’) * Block: Spatial replication of the treatments in
 each site * Drought: Types of drought (Early season drought or Late season
 drought)  * Drought.Time: Treatment combinations with the time of the
 season * cwmLDMC (mg/g): community-weighted leaf dry matter content and
 its SI unit * cwmSLA (cm2/g): community-weighted specific leaf area and
 its SI unit * Ash (g/kg): forage ash content and its SI unit *
 Protein_content (g/kg): forage crude protein and its SI unit * ADF (g/kg):
 forage acid detergent fibre and its SI unit * NDF (g/kg): forage neutral
 detergent fibre and its SI unit * WSC (g/kg): forage water soluble
 carbohydrate and its SI unit Note: The control plot data for Block III at
 site CH in 2015 were excluded due to several weeks of flooding.