Research On The Application Of City Sludge To The Cultivation Of Flowers And Plants

The city sludge is the sediment produced in the process of sewage treatment in a sewage treatment plant.The city sludge of Zhangzhou contains abundant organic nutrients and essential elements such as N,P,K for plant growth,and lower content of heavy metal elements.With the test method of potted soil cultivation,two approaches to the sludge were conducted,namely,the prescription of nutritional soil of sludge appropriate for the growth of chrysanthemum,and the effects of sludge compost on the growth of Salvia splendens,Petunia hybrida,and Tagetes patula,and some findings had been made,namely,the appropriate proportion of sludge compost to red soil,especially the best proportion of red soil to sludge compost.With the field test of sludge,the approach to the effects of application rates of sludge on the cultivation of Narcissus tazetta var.chinensis was conducted too.The conclution drew from the study was that city sludge could be applied to the production of flowers and plants as a good organic fertilizer.1.It was notable that the chrysanthemums' vegetative growth could be promoted,flowering period could be extended,and the number of flowers could be increased when three varieties of chrysanthemums were potted with nutritional soil of city sludge.The best prescriptions were:2 portions of city sludge+1 portion of pond sludge+3 portions of slag+3 portions of chaff dust, and 3 portions of city sludge+3 portions of slag+3 portions of chaff dust.The nutritional soil, which was inexpensive and worthy of popularization,was made of 2 portions of city sludge+1 portion of red soil+3 portions of slag+3 portions of chaff dust.It was a new way to dispose of and utilize city sludge with nutritional soil,which was partly made of city sludge,used to pot flowers and plants.2.Salvia splendens,Petunia hybrida,and Tagetes patula,all their vegetative growth could be promoted,flowering period could be extended,and the number of flowers could be increased notably when cultivated with sludge compost.The results showed that the flowering period of experimental group was 5-8 d longer than the control group,and the number of flowers of experimental group was 95.0%-137.5%higher than the control group.3.The cultivation effects varied with the sludge compost.With regard to flowering period,the best prescription to Salvia splendens,Petunia hybrida,and Tagetes patula was 60%sludge compost+40%red soil.The cultivation effects of this prescription were significant in promoting vegetative growth,extending flowering period and increasing the number of flowers.So the prescription of 60%sludge compost+40%red soil was suitable for cultivating annual and biennial herbs.4.The city sludge contains essential elements for plant growth and abundant organic materials. Rational application of city sludge could improve the fertility of soil,supply the nutrients necessary for the growth of Narcissus tazetta var.chinensis,and then promote notably its vegetative growth,increase its content of chlorophyll,enlarge the diameter of main bulb,and finally enhance its sale rating and value.The test showed that the best prescriptions were: "2250kg/hm~2 organic fertilizer of sludge+750kg/hm~2 calcium superphosphate+750kg/hm~2 composite fertilizer" and "3000 kg/hm~2 organic fertilizer of sludge+750kg/hm~2 calcium superphosphate+750kg/hm~2 composite fertilizer".The test provided a better reference for utilizing the city sludge to cultivate Narcissus tazetta var.chinensis.