Vegetation Surveys of Sites for Gully Remediation (NESP TWQ 2.1.4, CSIRO)

This dataset contains Vegetation and Biomass monitoring data collected for the NESP Project 2.1.4 (Demonstration and evaluation of gully remediation on downstream water quality and agricultural production in GBR rangelands). The aim of the vegetation monitoring in relation to this project is to track change in biomass and species composition over time on hillslope areas above gully erosion within control and treatment sites (treatments vary), linking to changes in downstream water quality. Data is from control and treatment gully sites on commercial grazing properties in the Burdekin being monitored as part of NESP Project 2.1.4.

The data in presented in this metadata are part of a larger collection and are intended to be viewed in the context of the project. For further information on the project, view the parent metadata record: Demonstration and evaluation of gully remediation on downstream water quality and agricultural production in GBR rangelands (NESP TWQ 2.1.4, CSIRO)

Monitoring of these sites is continuing as part of NESP TWQ Project 5.9. Any temporal extensions to this dataset will be linked to from this record.

BOTANAL files describe the biomass, species composition and species attributes such as basal area and cover for hillslope areas above gully erosion sites. PATCHKEY files describe the landscape condition (proportional) of vegetation patches for hillslope areas above gully erosion sites. And BIOMASS files describe the cover and biomass within the gully.

Methods:
Vegetation metrics were measured on the hillslope above each of the NESP gullies at the end of the dry season (‘EOD’, October–November) and then again at the end of the wet season (‘EOW’, April). Measurements were initiated in November 2016 at all sites except Mt Wickham which started in August 2018. Landscape and vegetation condition transects were installed upslope of the uppermost head section on both the treated and control gullies at all sites (Figure 8). Transects were run along slope contours and varied in length and spacing for each site depending on gully-head catchment size. Four to five transects were used at each treatment and control location. Each transect has a permanent marker at the beginning and end to facilitate repeat measures. Pasture metrics were recorded along each transect using a 1m2 quadrat based on the methods of Tothill et al., (1992), with placement of quadrats dependent on transect length at each site (30 quadrats were sampled for each treatment/control area). Metrics included the main pasture species and/or functional group composition and frequency, above-ground pasture biomass (DMY), total cover, litter cover, basal-area %, defoliation level and key soil surface condition metrics (Tongway and Hindley, 1995). In addition landscape condition was calculated along each transect using PATCHKEY (Abbott and Corfield, 2012). The condition assessments were aggregated to reflect ABCD landscape condition as used across grazed landscapes in the GBR catchments (Aisthorp and Paton, 2004; Chilcott et al., 2005; Bartley et al., 2014). Cover and biomass estimates were calibrated against standard quadrats taken at each site using classified quadrat photographs. Biomass standards were oven dried to attain dry matter yield, removing vegetation water retention error between treatments. A real time kinematic (RTK) survey ran from upslope of the vegetation survey to the valley section for each gully system.
Gully vegetation cover and biomass were also measured within each gully, on the gully walls and gully floor. Sampling was initiated at the end of the first wet season (April 2017) for all sites except Mt Wickham which started in August 2018. The sampling methodology was very similar to the hillslope survey. A minimum of three transects were measured across each gully, representative of the head, middle and valley sections. At each transect, % cover, biomass and dominant cover type was assessed using 0.25 m2 (0.5 x 0.5m) quadrats. Three quadrats were assessed on each wall (six in total) and six quadrats assessed in the deepest part of the channel in the gully floor. Box plots of the % cover and biomass data at the end of each wet season for control and treatment sites were analysed using Sigmaplot Version 14. In most cases a t-test for means and non-parametric Mann-Whitney rank sum test were conducted to evaluate differences between treatment and control sites

PATCHKEY data was collected at 5 parallel fixed transects above gully locations (hillslope area) – length and spacing of transects varied between sites dependant on hillslope size. PATCHKEY data was collected digitally using custom software on handheld android device. Survey occurs each year before and after wet season. Biomass is calibrated against cut and dried samples and cover is calibrated against classified quadrat photos – per collector. PATCHKEY is used to derive landscape condition from vegetation/grazed patches using vegetation and soil components to derive a condition state – it can be directly aggregated to match ABCD landscape condition. Condition state changes can be measured over time and related to water quality downstream.

BOTANAL is a comprehensive sampling and computing procedure for estimating pasture biomass and species composition (Tothill et al 1992) – these files describe the biomass, species composition and species attributes such as basal area and cover for hillslope areas above gully erosion sites.

Limitations of the data:
This dataset contains Vegetation monitoring data collected at these gully sites for end of the dry season (‘EOD’, October–November) for Hillslope only and then again at the end of the wet season (‘EOW’, April) for Hillslope and Gully over three reporting periods 2016-2017, 2017-2018 and 2018-2019. Measurements were initiated in November (EOD) 2016 at all sites except Mt Wickham which started in August (EOD) 2018.

Format:

This data collection consists of 3 zip files each monitoring period. Each zip file contains 4 CSV files and one Microsoft Excel file: Two BOTANAL CSV files – 1 EOD and 1 EOW, Two PATCHKEY CSV files – 1 EOD and 1 EOW

End of Wet season Gully_veg measurements are stored by season as Microsoft Excel file. Individual tabs for each site record the raw data as captured in the field. The “Stnds” tab calculated the calibration from BIO code to actual biomass. The “all_for_stats” sheet is the intermediate sheet for collation of data in “Wall” and “Channel” sheets ready for analysis in stats package. “Summary” tab contains summary data for the report.

Data Dictionary:

BOTANAL CSV headers:
ID: Unique identifier for sample
USER: Collector name/initials
SITE: Site name (abbreviation)
TRAN: Transect number (numbered from nearest to gully)
QUAD: Quadrat number per transect (numbered from left side – looking downhill)
DATE: Date and time
SP1 to SP5: Species name abbreviated using first two letters of genus and first three of species name eg. Bothriochloa pertusa = boper. Species recorded in order of highest biomass represented.
SPP1 to SPP5: Species proportion by weight of quadrat for each of species 1 to 5
YIELD: Total biomass estimate for quadrat in kg/ha
DEFOL: Estimated cattle defoliation of the pasture within quadrat. Categorical – 1=0-5%, 2=5-25%, 3=25-50%, 4=50-75% and 5=75-100%
BASAL: Estimated basal area of Perennial tussock grasses. % of quad
COVER: Foliage projected cover % of quad
LITTER: Litter cover % of quad
BARE: Bare ground % of quad (optional)
HARD: Soil hardness (after Tongway et al – landscape functional analysis). Categorical – 1=Easily broken, 2=Moderately hard, 3=Very hard, 4=Sand, 5=Self mulching.
DEPOS: Deposition from erosion processes, Categorical – 1=Insignificant, 2=slight, 3=moderate, 4=extensive
INCORP: Litter incorporation into soil surface. Categorical – 1=nil, 2=low, 3= moderate, 4=high
EROSION: Categorical – 1=Insignificant, 2=slight, 3=moderate, 4=extensive
COMMENT: Any comments about individual quadrat sample.

PATCHKEY CVS Headers:
ID: Unique identifier for sample
RECORDER: Collector name/initials
SITE: Site name (abbreviation)
TRAN: Transect number (numbered from nearest to gully)
PATCH_NO: Number of the patch occurring along a transect
DATE: Date and time
DOMINANT: Dominant vegetation functional group within a patch. See manual for categories
BASAL: Estimated basal area of Perennial tussock grasses. % of quad
LITTER: Litter cover % of quad
YIELD: Total biomass estimate for quadrat in kg/ha
WOODY: Presence of woody regrowth
BARE: Bare ground % of patch
EROSION: Categorical – 1=Insignificant, 2=slight, 3=moderate, 4=extensive
HARDNESS: Soil hardness (after Tongway et al – landscape functional analysis). Categorical – 1=Easily broken, 2=Moderately hard, 3=Very hard, 4=Sand, 5=Self mulching.
INCORPORATION: Litter incorporation into soil surface. Categorical – 1=nil, 2=low, 3= moderate, 4=high
PATCH_TYPE: Patch type classification auto-calculated in software from inputs
PATCH_EST: Patch type estimated by user – overrides calculated value
LAT: Latitude – if used with differential GPS can auto calculate patch length (optional)
LON: Longitude - if used with differential GPS can auto calculate patch length (optional)
PATCH_LENGTH: Measured patch length along transect
ACC: Accuracy of GPS coordinates
COMMENT: Any comments about individual patch samples

Fieldnames used in Gully_Veg XLSX spreadsheets:
Date – date of measurement
Quad – quadrat measured (not always numbered)
Loc – location on gully –cross sections from RTK. Numbers are in order from 1 nearest incrementing by 1 downstream
Pos – walls (left bank (lb), right bank (rb)) or channel
BIO – biomass code from 0 to 5 – this is a surveyor-specific estimate which is calibrated to actual biomass using standards
Cov – estimate of percent cover
Sp – species composition
COMMENT – any comments relating to the quadrat or measurement
Biomass (kg/ha) – biomass calculated using standards
Surveyor – surveyor number (different standards calibration required for different surveyors)

References:

Bartley, Rebecca; Hawdon, Aaron; Henderson, Anne; Wilkinson, Scott; Goodwin, Nicholas; Abbott, Brett; Baker, Brett; Matthews, Mel; Boadle, David; Jarihani, Ben (Abdollah). (2018) Quantifying the effectiveness of gully remediation on off-site water quality: preliminary results from demonstration sites in the Burdekin catchment (second wet season). RRRC: NESP and CSIRO. csiro:EP184204.

Baker, B., Hawdon, A. and Bartley, R., 2016. Gully remediation sites: water quality monitoring procedures, CSIRO Land and Water, Australia.

Abbott BN and Corfield JP (2012) PATCHKEY – A patch based land condition framework for rangeland assessment and monitoring, BACKGROUND INFORMATION AND USERS GUIDE. CSIRO, Australia.

Data Location:

This dataset is filed in the eAtlas enduring data repository at: data\nesp2\2.1.4-Gully-remediation-effects