報告書番号

U98056

タイトル（和文）

手賀沼ヘドロのコンポスト化処理と作製コンポストによるホウレンソウの栽培試験

タイトル（英文）

Composting of sludge in Lake Teganuma and cultivation of crop by soil added the compost.

概要 （図表や脚注は「報告書全文」に掲載しております）

手賀沼ヘドロを用いてコンポストを作製し、その成分分析を行うとともに、作製したヘドロコンポストによりホウレンソウの栽培試験を行った。その結果、作製したヘドロコンポスト中の亜鉛濃度は825ppmと高く、ヘドロと50％(w/w)の割合で混合したし尿汚泥由来のものと考えられた。従って、亜鉛濃度の低いし尿汚泥を利用するか、ヘドロと同様に重金属除去を行う必要がある。また、ホウレンソウの栽培実験において、ヘドロコンポストを添加した土壌での発芽率はほぼ100％であったが、ヘドロをそのまま添加した土壌では発芽率は80％以下に低下した。さらに、窒素、リン、カリウムの化学肥料とともにコンポストを添加した土壌において、ホウレンソウは良好な生育を示した。従って、手賀沼ヘドロから作製したコンポストの添加は、植物の生育に良好な効果をもたらすことが分かった。

概要 （英文）

Eutrophication has been a serious problem in Lake Teganuma, which is accelerated by domestic inflow. A large quantity of sludge is continuously accumulating in the bottom of the lake. A public enterprise has removed the accumulated sludge from the bottom every year. However, the removed sludge is used for only reclamation work. There is a great interest in new measures for a good riddance of the sludge. We have proposed a new measure that the accumulated sludge is effectively used as a compost for agricultural lands, since the sludge contains nitrogen, phosphorus, potassium and a variety of trace elements. In this paper, we made compost from the sludge and examined the effect of the compost on the growth of spinach. The made compost contained 825 ppm of zinc which is over the regulation of agricultural lands. The high concentration of zinc would derive from feces and urine that were equally (w/w) mixed with the sludge, since the concentration of zinc in the sludge was reduced from 735 ppm to 139 ppm by the electrochemical method. Therefore, we have to choose the feces and urine that contains low concentration of zinc or reduce the concentration of zinc in the mixed feces and urine by the electrochemical method. Spinach was cultivated by the compost mixed into soil. While 100 % seeds spouted in the soil added the compost, 80% seeds spouted in the soil added the untreated sludge. Furthermore, the growth of Spinach in the soil added the compost and chemical fertilizer (N, P, and K) was faster than that in the soil added the chemical fertilizer or the compost. These results show that the addition of compost to the agricultural lands is clearly effective for crop growth.

報告者

キーワード