珠江口红树林硫的累积和循环研究

主要研究了珠江口红树林硫的累积和循环特点，并探讨其对土壤中硫累积的影响．结果表明，珠江口五个红树群落硫的贮存量平均为１７０．４２ｋｇ／ｈｍ２；在群落硫元素的生物循环中，年存留量平均为１７．６０１ｋｇ／ｈｍ２，年归还量平均为３５．６０３ｋｇ／ｈｍ２，年吸收量平均为５３．２０４ｋｇ／ｈｍ２，周转期为３－８ａ，富集率均大于１．选定浅海沉积物的平均含硫量作为林下土壤成土母质的本底含硫量，估算红树植物生长后土壤含硫量的变化，并与群落硫的年归还量作比较．红树林对其林下土壤硫的累积作用有两方面，一是对海水硫的生物选择吸收与归还，二是为海水中的ＳＯ４（２－）为黄铁矿提供有机还原剂和嫌气微生物的能源，尤以后者的作用更重要．

Study on Sulphur Accumulation and Cycling in Mangrove Forest in Pear River Mouth

In this paper, the Characteristics of sulphur accumulation and cycling in mangrove Rhizophora apiculata Bl.) forest in the Pear River mouth are studied,and the effects on the sulphur accumulation in soil are discussed.Results show that,in the five halodrymia in the river mouth,the storage of sulphur is 170.42kg/hm2 on the average, and that in the sulphur biological cycling in the halodrymia, the annual reserve is 17.601kg/hm2, the annual retum 35.603kg/hm2, and the annual uptake 53.204kg/hm2, on the average. The turnover period is 3-8a, and all the enrichment rates are >1. The mangrove forest in two aspects affects the soil sulphur accumulation: the first is the biological selective uptake of the sulphur from the seawater and its retuming; and the second is the SO4(2-) in seawater changes into pyrites, thus providing organic reductants and anaerobic microbiological energy.