286
A. Simms
clams in a grid. An estimate of the market clam biomass was calculated using the
ArcView™ Query Builder and Field
Calculator. A market biomass is calculated by estimating the total number of clams in a
hectare grid. The estimation of the biomass is based on several assumptions and they
are:
1)
2)
3)
The clam densities are homogeneous within a 100 X 100 m grid.
It takes 1500 recruit size clams to make a bushel
One bushel of recruit size clams weights approximately 27 kilograms (Robert,
1981)
The biomass estimate for each grid is calculated as follows:
((clam density/m. sq. * grid area) /1500) * 27
(1)
The result is a clam shell weight in kilograms for each 100 x 100 grid. A grid is
economically viable only if the recruit clam density is greater than or equal to 10/m sq.
This criteria can be used with the ArcView™ Query Builder (Fig. 7) to select grids for
A. Simms
clams in a grid. An estimate of the market clam biomass was calculated using the
ArcView™ Query Builder and Field
Calculator. A market biomass is calculated by estimating the total number of clams in a
hectare grid. The estimation of the biomass is based on several assumptions and they
are:
1)
2)
3)
The clam densities are homogeneous within a 100 X 100 m grid.
It takes 1500 recruit size clams to make a bushel
One bushel of recruit size clams weights approximately 27 kilograms (Robert,
1981)
The biomass estimate for each grid is calculated as follows:
((clam density/m. sq. * grid area) /1500) * 27
(1)
The result is a clam shell weight in kilograms for each 100 x 100 grid. A grid is
economically viable only if the recruit clam density is greater than or equal to 10/m sq.
This criteria can be used with the ArcView™ Query Builder (Fig. 7) to select grids for