Accession Number : ADA317203

Title :   A Simulation Model for Growth of the Submersed Aquatic Macrophyte Hydrilla (Hydrilla Verticillata (L.F.) Royle).

Descriptive Note : Final rept.

Corporate Author : ASCI CORP VICKSBURG MS

Personal Author(s) : Best, Elly P. ; Boyd, William A.

PDF Url : ADA317203

Report Date : SEP 1996

Pagination or Media Count : 96

Abstract : A simulation model for the biomass dynamics of the submersed macrophyte Hydrilla verticiltata (dioecious biotype) is presented. The model HYDRIL is based on carbon flow within a l-m2 water column. It includes several aspects that affect biomass dynamics, such as latitude, seasonal changes in climate, pH and oxygen effects on CO2 assimilation rate at light saturation, wintering strategies, grazing (removal of aboveground and tuber biomass), and mechanical control (removal of aboveground biomass). The characteristics of the community and of the site can be easily modified by the user. HYDRIL incorporates insights into the processes affecting the dynamics of a Hydrilla community in relatively shallow, hard water (0.1- to 2.5-m depth; DIC concentration > 0.8 mmol). It has been calibrated on data pertaining to a Hydrilla community in Lake Orange, Florida. At that site, no aboveground wintering biomass is present and growth starts from the tuber bank. Peak biomass is reached late in August and tuber formation takes place in autumn, replenishing the tuber bank. HYDRIL simulates the dynamics of plant biomass and tuber bank density at Lake Orange well over a period of 1 to 5 years. It has been used to calculate plant biomass and tuber density for other sites in subtropical (Florida) and tropical (India) areas, where it simulated biomass ranges similar to those measured in the field.

Descriptors :   *COMPUTERIZED SIMULATION, *PLANT GROWTH, *AQUATIC PLANTS, COMPUTER PROGRAMS, INDIA, PEAK VALUES, REMOVAL, LIGHT, CARBON, NITROGEN, SATURATION, OXYGEN, SEASONAL VARIATIONS, CLIMATE, TROPICAL REGIONS, CALIBRATION, SOLAR RADIATION, SUBROUTINES, LAKES, FLORIDA, ALKALINITY, LATITUDE, SUBTROPICAL REGIONS, BIOMASS CONVERSION, PHOTOSYNTHESIS, AUTUMN, HARD WATER.

Subject Categories : Biology
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE