Ecology of the Tres Rios Constructed Treatment Wetland, Phoenix, AZ: 2011-2015
Author(s):
- Daniel Childers, Arizona State University
- Christopher Sanchez, Arizona State University
- Nicholas Weller, Arizona State University
Abstract:
Constructed treatment wetlands provide cost effective and ecosystem-service based solutions to the problem of urban water reuse. They are a particularly attractive option for water reuse in arid urban systems where water resources are scarce, and understanding how they function in these environments is critical to facilitating sustainable water use practices. Although constructed treatment wetlands are well established and studied in mesic climates, how they function in and respond to hot, arid climates is comparatively not well understood. Specifically, large atmospheric water losses via evaporation and plant transpiration may comprise a much larger component of the whole-system water budget than in mesic climates. Additionally, given the primary role that emergent macrophytes play in nutrient removal, particularly nitrogen removal, the effects of plant community composition and primary productivity patterns on system performance in the context of aridland constructed treatment wetlands have not been extensively studied.
Our goal was to develop a model of how these "working wetlands" perform in arid climates by developing and comparing nutrient and water budgets. At the Tres Rios constructed treatment wetland in Phoenix, AZ, USA, we measured atmospheric water losses via evaporative pathways (plant transpiration and open water evaporation) as well as inorganic N fluxes between the whole system and the vegetated marsh areas. Total water losses via evaporative pathways peaked at 300,000 m3 month-1 (714 L H2O m-2 month-1) in the hot summer months and represented more than 70% of the whole-system water budget over a 27 month time period. These evaporative losses are nearly an order or magnitude higher than rates observed in mesic systems. Peaks in above-ground biomass ranged from 1586±179 to 2666±164 gdw m-2, with Typha spp. accounting for up to 2/3 of total biomass. Overall, the vegetated marsh removed almost all of the inorganic N supplied to it, and large transpirative water losses were observed to move large volumes of replacement water into the marsh via a plant-mediated "biological tide". This process providing additional opportunities for soil microbes and emergent macrophytes to process target solutes, and potentially enhancing the treatment efficacy of the aridland Tres Rios constructed treatment wetland relative to more humid and mesic systems.
Keywords:
Temporal Coverage:
2011-07-01 to 2015-09-30Geographic Coverage:
Geographic Description: CAP LTER study areaBounding Coordinates:
Longitude:-112.266973 to -112.254519
Latitude:33.39871 to 33.387462
Contact:
Data Manager, Julie Ann Wrigley Global Institute of Sustainability, Arizona State University,PO Box 875402,Tempe
Methods used in producing this dataset: Show
Data Files (3) :
Tabular: 633_primary_productivity_76f2e1c522420abe21fdfba791fab9b0.csv
Description: Tres Rios: indices of primary productivity. Measurements of various physiological characteristics of individual plants located within study transects at the Tres Rios wetlands. These data are used as inputs into biomass models to calculate above-ground primary productivity.
Column | Description | Type | Units |
---|---|---|---|
date | date on which sample was collected |
Format: YYYY-MM-DD | |
transect | transect in which measurement was collected |
||
species | plant species on which measurments were collected |
||
quadrat | location of quadrat along the transect |
||
notes | "airboat trail" or "thatched" indicates anthropogenic or natural toppling of plant stands, respectively |
||
biomass | biomass |
gram | |
cdb | culm diameter at base |
centimeter | |
longest_leaf | longest leaf |
centimeter | |
num_leaves | number of leaves |
number | |
num_seed_stems | number of seed stems at plant tip |
number | |
pistillate_length | pistillate length |
centimeter | |
pistillate_width | pistillate width |
centimeter | |
stem_height | stem height |
centimeter | |
stem_volume | stem volume |
cubicCentimeter | |
sum_leaf_lengths | sum of leaf lengths |
centimeter |
Tabular: 633_transpiration_86e9ed7bb77ec9ca676eb26316acd147.csv
Description: Tres Rios: transpiration. Measurements of leaf-level gas exchange and micro-climate taken using an infrared gas analyzer on individual plant leaves located within study transects at the Tres Rios wetlands. These instantaneous micro-climate and transpiration data are used as inputs into transpiration and evaporation models that scale these data and estimate whole-system atmospheric water losses.
Column | Description | Type | Units |
---|---|---|---|
datetime | date and time of data collection |
Format: YYYY-MM-DD HH:MM:SS | |
transect | transect in which measurement was collected |
||
observation_number | sequential order in which samples were taken on a given day |
||
section | vertical location along plant where measurement was taken, where T is the tip of the leaf/stem, B = the bottom of the leaf/stem, and and numbers represent the total distance (cm) above the the water surface |
||
species | plant species on which measurements were collected |
Enumeration:
|
|
BLCond | total boundary conductance |
molesPerMeterSquaredPerSecond | |
ci | intercellular CO2 concentration |
micromolesPerMole | |
CO2R | reference cell CO2 |
micromolesPerMole | |
CO2S | sample cell CO2 |
micromolesPerMole | |
cond | conductance to H2O |
molesPerMeterSquaredPerSecond | |
Flow | flow rate to the sample cell |
micromolesPerSecond | |
H2OR | reference cell H2O |
micromolesPerMole | |
H2OS | sample cell H2O |
micromolesPerMole | |
leaf_area | leaf area |
squareCentimeters | |
PARi | in-chamber quantum sensor |
micromolesPerMeterSquaredPerSecond | |
PARo | external quantum sensor |
micromolesPerMeterSquaredPerSecond | |
photo | photosynthetic rate |
micromolesPerMeterSquaredPerSecond | |
RH_R | reference cell relative humidity |
dimensionless | |
RH_S | sample cell relative humidity |
dimensionless | |
RHsfc | relative humidity taken at the leaf surface |
dimensionless | |
stm_rat | stomatal ratio estimate |
dimensionless | |
Tair | air temperature |
celsius | |
TBlk | cooler block temperature |
celsius | |
Tleaf | leaf temperature |
celsius | |
trmmol | transpiration rate |
millimolesPerMeterSquarePerSecond | |
VP | vapor pressure |
kilopascal | |
VpdA | vapor pressure deficit based on air temperature |
kilopascal | |
VpdL | vapor pressure deficit based on leaf temperature |
kilopascal |
Tabular: 633_water_quality_c389fa01eeb9aaa17c6694722e0ded8e.csv
Description: Tres Rios: water_quality. Measurements of water quality taken in situ and from grab samples collected within study transects at the Tres Rios wetlands.
Column | Description | Type | Units |
---|---|---|---|
date | date of data collection |
Format: YYYY-MM-DD | |
year | year of data collection |
Format: YYYY | |
month | month of data collection |
Format: MM | |
transect | transect in which measurement was collected |
||
location | location sample was taken within transect |
||
notes | sampling or processing notes |
||
Cl | chloride (Cl) |
milligramsPerLiter | |
conductance | conductance |
microsiemenPerCentimeter | |
DO | dissolved oxygen |
milligramsPerLiter | |
DOC | dissolved organic carbon |
milligramsPerLiter | |
%DOsat | percent dissolved oxygen saturation |
dimensionless | |
NH4 | ammonium-nitrogen (NH4-N) |
milligramsPerLiter | |
NO2 | nitrite-nitrogen (NO2-N) |
milligramsPerLiter | |
NO3 | nitrate-nitrogen (NO3-N) |
milligramsPerLiter | |
pH | pH |
dimensionless | |
PO4 | phosphate-phosphorus (PO4-P) |
microgramsPerLiter | |
speccond | specific conductance |
microsiemenPerCentimeter | |
TDN | total dissolved nitrogen |
milligramsPerLiter | |
Temp | water temperature |
celsius | |
TN | total nitrogen |
milligramsPerLiter | |
TP | total phosphorus |
milligramsPerLiter |