砂姜黑土是我区面积较大的低产土壤,主要分布在临沂、郯城、苍山平原河间洼地,约占三县总耕地面积的57%,由于地势低洼,十年九涝,茅草丛生,土壤瘦瘠,因而粮食产量长期低而不稳,成为我区农业生产上的“坠脚田”。近几年来,我们在总结群众改土经验的基础上,于1975年秋开始在临沂县王桥公社洪 Shajiang black soil is a large area of ​​low-yielding soil in our area, mainly in Linyi, Tancheng, Cangshan plain heavey depression, accounting for 57% of the total area of ​​three counties, due to low lying, ten years of nine floods, thatched, soil Thin barren, so long-term low and unstable grain output, agricultural production in our region as “falling foot.” In recent years, on the basis of summing up the experience of the masses in earth improvement, we started to work in Hongqiao, Linyi County, in the autumn of 1975