ENG  Vol.9 No.6 , June 2017
Design Concept of an Automated Irrigation System for Simulating Saltwater Intrusion in a Mesocosm Experiment
Abstract: Coastal wetlands make up about one third of the overall wetland area in the conterminous United Stated based on the Environmental Protection Agency 2016 [1]. Sea-level rise is expected to elevate water salinity and effect carbon sequestration, nitrogen removal, further alter plant communities and shift ecosystem function. To promote understanding of the influence of seawater intrusion into tidal freshwater wetlands, we designed a mesocosm experiment with automated irrigation system at Spring Hill, Storrs, CT, USA (41.8°N, 72.3°W). To simulate marine water intrusion, we designed an automated irrigation to work for an on-going mesocosm experiment, which is composed of 64 tanks with 4 wetland species: Carexstricta, Spartinapectinata, Typhalatifolia, Phragmitesaustralis. During low tide, solenoid valves quantify water based on the instruction of system core controller (Arduino) and water is distributed to assigned tank [2] [3]. During high tide, water is pumped up into assigned tank, salinity is varied with plant species, Carexstricta and Spartinapectinata are fresh water species, Typhalatifolia, Phragmitesaustralis are brackish water species. The manipulation core of system is an open-source microcontroller platform. The irrigation system was designed daily twice change from low tide water level to high tide water level, and same water tank should keep at constant salinity within 30 days. Staff just needs monthly visit to add sea salts, the raw material of artificial seawater. Ecosystem CO2 and CH4 gas exchanges were measured monthly from May to September 2015 using large transparent chambers that enclosed emergent plants and the soil surface; field sampling and analysis procedures followed [4]. The simulated saltwater intrusion results are expected to alter plant growth, emission of carbon dioxide, methane and other greenhouse gases, and effect interaction with coastal marsh ecosystem.
Cite this paper: Xu, C. (2017) Design Concept of an Automated Irrigation System for Simulating Saltwater Intrusion in a Mesocosm Experiment. Engineering, 9, 563-574. doi: 10.4236/eng.2017.96035.

[1]   Environment Protection Agency. Coastal Wetlands.

[2]   Ferrarezi, R.S., Dove, S.K. and van Iersel, M.W. (2015) An Automated System For Monitoring Soil Moisture and Controlling Irrigation Using Low-Cost Open-Source Microcontrollers. Hort Technology, 25, 110-118.

[3]   Miller, L.P. and Long, J.D. (2015) A tide Prediction and Tide Height Control System for laboratory Mesocosms. PeerJ, 3, e1442.

[4]   Neubauer, S.C. (2013) Ecosystem Responses of a Tidal Freshwater Marsh Experiencing Saltwater Intrusion and Altered Hydrology. Estuaries and Coasts, 36, 491- 507.

[5]   Kao-Kniffin, J., Freyre, D.S. and Balser, T.C. (2010) Methane Dynamics across Wet- land Plant Species. Aquatic Botany, 93, 107-113.

[6]   Lawrence, B.A., Lishawa, S.C., Hurst, N., Castillo, B.T. and Tuchman, N.C. (2017) Wetland Invasion by Typha × glaucaincreases Soil Methane Emissions. Aquatic Bo- tany, 137, 80-87.

[7]   Mozdzer, T.J. and Megonigal, J.P. (2013) Increased Methane Emissions by an Intro- duced Phragmitesaustralis Lineage under Global Change. Wetlands, 33, 609-615.

[8]   Martin, R.M. and Moseman-Valtierra, S. (2015) Greenhouse Gas Fluxes Vary between Phragmitesaustralis and Native Vegetation Zones in Coastal Wetlands along a Salinity Gradient, Wetlands, 35, 1021-1031.

[9]   Connecticut Weather and Live, Tides Charts and Graphs for Connecticut River.

[10]   Lee, D.Y., De Meo, O.A., Thomas, R.B., Tillett, A.L. and Neubauer, S.C. (2016) Design and Construction of an Automated Irrigation System for Simulating Saltwater Intrusion in a Tidal Freshwater Wetland. Wetlands, 36, 889-898.

[11]   Arduino 2560 Open-Source Electronic Platform Home Page (2017).

[12]   Solenoid Valve Home Page (2017).

[13]   Parameswaran, G. and Sivaprasath, K. (2016) Arduino Based Smart Drip Irrigation System Using Internet of Things. International Journal of Engineering Science and Computing, 6, 449-456.

[14]   Floating Sensor Home Page (2017).

[15]   Peristaltic Pump Home Page (2017).