蚯蚓和发酵牛粪促进南瓜苗修复PAHs污染农田土壤

为了寻求高效修复土壤中持久性有机污染物多环芳烃(PAHs,polycyclic aromatic hydrocarbon),在温室盆栽试验条件下,研究接种蚯蚓和施用发酵牛粪对南瓜苗修复3环以上PAHs污染土壤的影响。试验设置施用牛粪(D)、单接蚯蚓(E)、接种蚯蚓和施用牛粪(ED)、不接种蚯蚓和不施用牛粪的对照(CK)共4个处理,播种10周后收获。研究结果表明,接种蚯蚓和施用牛粪的共同作用下能有效提高南瓜苗生物量,有利于南瓜苗在PAHs污染的土壤生长,特别是地上部分的生长;接种蚯蚓或/和施用牛粪有效地提高了南瓜苗从土壤中吸收3～5环PAHs化合物的效率,且南瓜苗地上部吸收的PAHs量最低是地下部的6倍。因此,结合蚯蚓和发酵牛粪的辅助作用,南瓜苗地上部生物量较大,能从土壤中吸收多种PAHs化合物,与仅依赖于土壤自身的作用相比,三者的共同作用使得土壤中3环以上PAHs化合物的去除率提高23%以上,可组合应用于PAHs污染土壤的强化修复。该研究为土壤多环芳烃污染修复提供参考。     

改进型生物过滤器对H_2S和NH_3混合气体去除效果的研究

生物过滤器去除恶臭气体的影响因素包括进气的容积负荷、填料湿度、填料层高度、填料中微生物种群和数量及填料层成分的变化,为进一步了解生物过滤器的去除效果,共设计4个处理组,分别编号为A、B、C和D,用猪粪堆肥、珍珠塔、活性蚯蚓粪和锯末按不同比例组成生物过滤器填料,并添加除臭优势菌种和蚯蚓处理H2S和NH3。结果表明,生物过滤器填料中微生物数量丰富,细菌和真菌在最高的C组分别达到（2.23～3.26）×1010cfu·g-1和（2.00～3.08）×105cfu·g-1。在生物过滤器填料中各种形态氮和硫的分布不均匀,NH4＋-N与S2--S由下向上递减,而NO3--N起初是下部高于上部,但随着运行时间的延长,上部的NO3--N逐渐高于下部。在该生物除臭系统中,用活性蚯蚓粪、堆肥和锯末混合填料（C）处理效果最好,是很好的生物过滤器填料,有存活的蚯蚓,其余3个处理均没有存活的蚯蚓。     

蚯蚓引入垂直流-水平潜流湿地混流系统处理沼液的效果

为了避免或减少人工湿地处理厌氧发酵液发生堵塞,并提高系统处理效果,该试验将蚯蚓引入到垂直流湿地系统中,并与水平潜流湿地构成混流系统,用来处理厌氧发酵液。结果表明:采用蚯蚓垂直流湿地-水平潜流湿地混流系统处理厌氧发酵液,在进水平均有机负荷达1.82 kg/(m~2·d),水力负荷10、20 cm/d的条件下,对化学需氧量、总磷、总悬浮固体的去除率达到了90%以上,氨氮去除率达80%以上,总氮去除率也维持在60%以上。提高水力负荷对污染物的消减量更有优势,水平潜流湿地对总氮的消减优于蚯蚓生态湿地。2种水力负荷下,混流湿地出水化学需氧量、氨氮、总磷、总悬浮固体均能达到《畜禽养殖业污染物排放标准》要求。蚯蚓使混流系统对化学需氧量、氨氮、总凯氏氮的去除分别提高了2%、12%、4%,同时具有同步处理污水污泥,缓解湿地堵塞的效果,处理水质基本达标,处理污泥的成本也大大降低,因此具有很大应用潜力。     

Impact of cultivation management in an agroecosystem on hot spot effects of earthworm middens

In comparison to the surrounding soil, hot spot effects of middens of the epianecic earthworm Lumbricus terrestris were determined under different field conditions on a loamy sand. The impact of 3 different management systems was studied: 1. unmulched; 2. straw mulching; 3. intermediate crop: Sinapis alba. Furthermore, we considered 2 different crops (bean, lupine) and their growth stages. We monitored different enzyme activities and abiotic parameters of soil at 6 sampling dates between April and August 1998 parallel to abundances of microfauna (soil protozoa) and mesofauna (Enchytraeidae, Collembola, mites). The analysis of earthworm middens revealed enhanced enzyme activities and increased mesofaunal abundances. Differences between midden and reference samples were significant during the whole vegetation period and became maximal during ripening of crops. We found a distinct but not significant increase in individual numbers of soil flagellates in midden areas during leafing and heading of crops. Values of the studied parameters tended to be higher in bean plots but generally the crop impact on midden properties was not significant. Our results showed a significant positive synergistic effect between earthworm middens and intermediate crop. Straw mulching supported the hot spot effects of middens.     

Effect of biosolid amendment on enzyme activities in earthworm (Lumbricus terrestris) casts

We studied the effect of amendment of sewage sludge biosolids on enzyme activity in soil and earthworm (Lumbricus terrestris) casts. Enzyme activities and contents of nutrients and organic matter of surrounding soil were compared with the corresponding properties of earthworm casts. This short time experiment was conducted at 20 ± 0.5 °C in the laboratory, simulating field conditions of biosolid treatments. In general, all of doses of biosolid treatments influenced the enzyme activity and contents of nutrients and organic matter of earthworm casts and surrounding soil. Enzyme activity such as urease (UA), alkaline phosphatase (APA), and arylsulfatase (ASA) and the contents of organic matter and nutrients N and P in earthworm casts and surrounding soil increased with increasing biosolid application. Without biosolid additions, enzyme activities in cast of L. terrestris exceeded those in the soil. In contrast, when biosolid was added, DHA in casts was lower than the soil. Activities of UA and APA were consistently higher in L. terrestris casts than in soil of all biosolid treatments. Biosolid amendments generally increased ASA at low doses, but at higher doses, ASA decreased. In general, organic matter and contents of N and P were higher in surface casts of L. terrestris and soils than in the control soil. Activities of UA, APA, the contents of organic carbon and nutrients N and P in soil and casts showed positive correlations. On the contrary, ASA and DHA were negatively correlated with the contents of organic matter and nutrients.     

蚯蚓对土壤中杀虫剂的回避行为——一种用于土壤健康质量快速诊断的装置和方法

通过设计一套试验装置，研究了蚯蚓对土壤中杀虫剂的回避行为。结果显示，蚯蚓对某些杀虫剂非常敏感，土壤中杀虫剂含量达到其半致死浓度(LC50)的l／5～l／25时，即出现明显的逃逸或迁移行为。     

蚯蚓抗菌肽对贵州黄鸡生产性能的影响研究

为了考察蚯蚓抗菌肽对贵州黄鸡生产性能的影响,试验采用单因素试验设计,共设4个抗菌肽添加水平,分别是0%、0.6%、0.8%和1.0%。选用0日龄健康贵州黄鸡120只,根据体重随机分为4组,分别为对照组和试验Ⅰ、Ⅱ、Ⅲ组,每组分别设3个重复,每个重复10只鸡。试验期21 d。试验结果表明:日粮中添加抗菌肽对贵州黄鸡的采食量无显著影响(P>0.05),但显著提高日均增重(P<0.05),降低料重比(P<0.05),降低发病率和死亡率(P<0.05),以添加1%水平的蚯蚓抗菌肽效果为佳。