Effects Of Seawater And Mariculture Wastewater Irrigate Helianthus Tuberosus L. And Oil Sunflower

It is a new way, to use seawater and mariculture wastewater irrigates salt-tolerant crops, for the littoral development of sustainable agriculture. It can save the freshwater, avoid the pollution which mariculture wastewater directly discharged into sea without pre-treated, and gain some economic benefit. My experiment includes two sections, one is greenhouse experiment, and another is field experiment. Sand culture experiments were carried out to study the effects of different concentrations of seawater on the growth, mineral nutrition absorption characteristics, photosynthesis and chlorophyll fluorescence characteristics of oil sunflower during the seedlings stage. The salt-tolerant physiology mechanism of oil sunflower under seawater treatment was explored from different points so as to provide theory basis to mariculture wastewater irrigation. The field experiment of mariculture wastewater irrigate Helianthus tuberosus L. and oil Sunflower were carried out in 2004 and 2005 in Laizhou, Shandong Province. The experiment set six treatments, were non-irrigation (CK1), freshwater irrigation (CK2), slightly saline water irrigation (CK3), mariculture wastewater blended with slightly saline water irrigation 1:1,1:2, 1:4 treatment. From the field experiment, we studied mariculture wastewater blended with slightly saline water irrigating Helianthus tuberosus L. and oil Sunflower on crop growth, soil safety after irrigation, water use efficiency and soil water content during Helianthus tuberosus L. growing season.The results were showed as below: Sand culture experiments in greenhouse:(1) Compared with the control, the plant height, stem width, DW(dry weight) and the contents of nitrogen and phosphorus decreased significantly under high concentration seawater treatment(40% seawater).The S_K,Na in root, stem and leaves were very low under this treatment. And the chlorophyll content, photosynthesis and chlorophyll fluorescence parameter were greatly reduced. It was indicated that high concentration seawater seriously restraind the growth and photosynthesis of oil sunflower.(2) Under low concentration seawater treatment (10% and 20% seawater), the plant height,...