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selection were its high growth rate; its size, structure, and growth 

 patterns which allow it to be mechanically harvested; its long life 

 and continuous or year-round growth cycle; photosynthate translo- 

 cation within the plant tissues that counters problems of self- 

 shading; and very high nutrient absorption capabilities resulting 

 from the extensive exposed blade surfaces. 



Giant kelp is, and has been since the 1930's, commercially har- 

 vested off the coast of California for use as a food additive and 

 animal feed supplement. Recent harvests have been running be- 

 tween 100,000 and 160,000 tons a year. Institutionally speaking, 

 this existing practice is a plus. Moreover, kelp's widespread natural 

 occurrence and the success of laboratory growth experiments plus 

 the natural growth of other algae in waters of the three major 

 coastal zones of the continental United States indicate that many 

 of our waters may be utilized as site locations for commercial kelp 

 farms. 



Studies and economic analyses of potential commercial systems 

 performed to date have shown that kelp yield per acre of ocean 

 farm area, using deep water as the source of fertilizer, is one of the 

 key parameters affecting both initial capital requirements and unit 

 gas costs. Projections of kelp yield potential were made based on 

 the range of Macrocystis crop densities observed in natural beds 

 coupled with observations of several investigations of the range of 

 growth rates in adult plants. This study suggested the range of 

 yields that are potentially achievable. The study predicts yields 

 ranging from 25 dry, ash-free tons per acre per year, up to 105 dry, 

 ,ash-free tons per acre per year, assuming continuous fertilization, 

 in order to provide a data base on yield of a large number of adult 

 plants, under controlled conditions, we have, in cooperation with 

 the Department of Energy, designed, constructed, and installed a 

 test farm in the open ocean approximately 5 miles off the coast of 

 southern California to be used as an experimental station to con- 

 duct kelp yield experiments on 100 adult kelp plants in a con- 

 trolled fertilization environment. 



Yield experiments will be conducted by the California Institute 

 of Technology through funding provided by the Department of 

 Energy under a separate contract. 



To date, the gas industry has provided $3.4 million and the DOE 

 has provided $3.6 million to this program. The DOE programed 

 $1.2 million in fiscal year 1978 funds to maintain the schedule of 

 deploying the test farm. In fiscal year 1980, the program is budget- 

 ed for a total of $6.2 million, with DOE contributing $3.5 million, 

 GRI $2.4 million, and New York State ERDA $355,000. 



Since the farm was deployed approximately 1 year ago, much has 

 been learned. Last December, 100 adult plants were transferred 

 from shallow waters near shore, where they had been stored, to the 

 test farm. A curtain, designed to retain upwelled nutrients and 

 protect the plants from abrasion on the structure, was then in- 

 stalled around the farm and a period of observation and data 

 collection was begun, including weekly measurements of growth of 

 juvenile fronds, analysis of dissolved nutrients in water samples, 

 and blade tissue analysis. 



Initial observations of curtain performance based on underwater 

 photography and plant tissue analysis provided clear evidence of 



