蚯蚓养殖对幼龄胶园土壤养分及橡胶树根系生长的影响

本研究旨在探讨林下蚯蚓养殖对幼龄胶园土壤养分及橡胶树根系生长的影响。以牛粪作为原料,于 2017 年 4—11 月在 4 年生幼龄胶园铺设粪垄养殖蚯蚓,并测定土壤养分和根系生长情况。结果表明,与对照（CK）相比,铺设粪垄无蚯蚓养殖（WQ）和铺设粪垄蚯蚓养殖（Q）处理总体上可显著提高土壤硝态氮、速效磷、速效钾和土壤水分含量以及土壤 pH,而对土壤铵态氮、有机质、微生物活性及微生物群系数量无显著影响（p<0.05）;和 CK 相比,WQ和 Q 处理显著促进根的生长,并提高吸收根的比例（p<0.05）。综上所述,在幼龄胶园养殖蚯蚓短期内（半年）可提高土壤速效养分含量,促进根系生长。     

蚯蚓对秸秆-污泥混合物的消解转化效果

为了探明蚯蚓对秸秆与污泥混合物的消解转化效果,在实验室条件下进行了模拟培养试验。试验共设不同配比混合物料6个处理,即水稻秸秆与城市生活污泥的质量比分别为0/100、10/90、20/80、30/70、40/60和50/50,各处理混合物料接种蚯蚓后在常温下培养。根据物料的消耗情况进行计量补充,并根据需要及时补充水分,始终维持培养料湿润。培养6星期后,去除未被消解的混合物料,分离并计测蚯蚓重量与蚓粪有机肥重量及养分含量,计算混合物料的消解量。结果表明,在本试验条件下,掺入10%-30%秸秆显著提高蚯蚓对混合物料的消解速率。掺入10%和20%秸秆的处理蚯蚓生物量的增长速率显著高于掺入50%秸秆的处理。掺入10%-50%秸秆均显著提高蚯蚓转化污泥-秸秆混合物料形成有机肥的速率。蚓粪有机肥的有机质含量随着掺入秸秆比例的增加而提高;全氮和全钾含量无显著影响;与单纯采用污泥相比,当掺入秸秆比例达40%和50%时,蚓粪全磷含量显著降低。     

蚯蚓对不同分解阶段有机质的响应

This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical areas of China. Two plantations were selected as the study sites: Site Ⅰ was dominated by the exotic endogeic earthworm species Ocnerodrilus occidentalis; Site Ⅱ was dominated by epigeic species Amynthas corticis. After the fallen litter and earthworms were removed or expelled, four treatments were set up as: reserving the top soil (0-5 cm, equal to H layer) (H), removing the top soil and adding fresh litter (Le), removing the top soil and adding semi-decomposed litter (Li), and a control with no top soil nor any litter (CK). Five randomized blocks that were enclosed with nylon nets on the top were set up in each site, and then the four treatments were arranged randomly in each block. After 2-3 months, earthworms were collected using the formalin method. The results showed that Ocnerodrilus occidentalis preferred Treatment H though it was found in Treatments Le and Li as well; Amynthas corticis preferred Treatment Li though sometimes it also appeared in Treatment H; and Amynthas sp., another epigeic species, was mainly present under Treatment Le and only appeared in Treatment H occasionally. These findings confirmed that earthworm species belonging to different ecological groups had different responses to organic matter at different decomposition stages. The impacts of earthworm communities dominated by O.occidentalis mainly appeared at the later periods of litter decomposition.     

蚯蚓堆肥污泥研究述评

近年来,蚯蚓堆肥作为污泥处理的新选择,成为大家关注的热点之一。从适合于污泥堆肥蚓种的选取、蚯蚓堆肥处理前后污泥理化性质的改变、蚯蚓自身的变化、蚯蚓对重金属的富集去除作用和以植物生长分析法评估污泥处理的效果等方面对污泥蚯蚓堆肥的研究进展进行了述评,以期为污泥处理的相关研究和实际应用提供参考。     

改进型生物过滤器对H2S和NH3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。     

蚯蚓体表自润滑仿生应用试验研究

对蚯蚓体表自润滑行为进行分析,并设计5种仿生润湿试件:通孔型、阶梯孔型、通孔倒角型、插销型以及复合型,以水为润滑剂,通过润湿试验,探讨润湿规律,为蚯蚓耦合仿生研究提供设计依据。结果表明,无论是覆盖玻璃还是有机玻璃,通孔型的喷嘴润湿整个表面所需的时间最长,而通孔倒角型喷嘴所需时间最短;在同一流速条件下、同一时间间隔内,各仿生润湿试件按润湿面积由大到小依次是:通孔倒角型、插销型、复合型、阶梯孔型、通孔型。     

蚯蚓粉替代鱼粉对大鳞副泥鳅生长、肌肉成分、血清生化指标及免疫性能的影响

以初始体重为(3.86±0.23)g的大鳞副泥鳅(Paramisgurnus dabryanus)为试验对象,研究蚯蚓(Eisenia foetida)粉替代鱼粉对其生长、肌肉成分、血清生化指标及免疫性能的影响。以0代替鱼粉为对照组,用蚯蚓粉替代25%、50%、75%、100%的鱼粉配制成5组等氮等能饲料,在网箱中进行10周的养殖试验。结果显示,饲料中的蚯蚓粉替代鱼粉对大鳞副泥鳅的存活率无显著影响;随着替代水平的升高,饲料系数、增重率升高(P0.05),肥满度、肝体比降低(P0.05)。各组间脾体比、特定生长率均无显著性差异;75%和100%替代组肌肉粗脂肪含量显著高于对照组(P0.05),100%替代组粗蛋白和水分含量显著低于对照组(P0.05)。随着饲料中蚯蚓粉水平的上升,鱼体肌肉蛋白质的精氨酸、胱氨酸、天门冬氨酸含量升高(P0.05),脯氨酸、组氨酸、蛋氨酸、苏氨酸、苯丙氨酸含量显著降低(P0.05);各组间血清谷丙转氨酶活力、高密度脂蛋白胆固醇含量、脂肪酶和淀粉酶活性均无显著性差异(P0.05)。随着代替水平的上升,血清甘油三酯和总胆固醇含量显著升高(P0.05),谷草转氨酶显著降低(P0.05);随着替代水平的继续上升,肝胰脏过氧化氢酶、谷胱甘肽过氧化物酶、溶菌酶活力下降,肝胰脏丙二醛含量、碱性磷酸酶活力、攻毒后的发病率和死亡率上升。各组间的肝胰脏总超氧化物歧化酶活力和总抗氧化能力均无显著性差异(P0.05)。研究表明,本实验条件下,蚯蚓粉可部分替代(22%)饲料鱼粉而不影响大鳞副泥鳅的生长和存活,且能提高鱼体肌肉成分,有效预防肝胰脏损伤和过氧化,但显著降低了鱼类免疫性能(P0.05)。     

蚯蚓处理石灰法造纸废水沉降物试验

以引进的大平２号蚯蚓及本地两种蚯蚓进行了不同品种蚯蚓处理石灰法造纸废水沉降底泥的饲养试验,结果表明：大平２号蚯蚓处理效果明显好于本地环毛蚓和异唇蚓,大平２号蚓单卵平均孵化４．４条,在底泥中从幼蚓长为成蚓约需６０ｄ,每天每克蚯蚓消耗底泥０．９７ｇ左右     

蚯蚓(Eisenia foetida)对水稻土中Cd的富集及其氧化应激

以赤子爱胜蚓(Eisenia foetida)为模式生物,研究其暴露于不同外源Cd浓度(0～10 mg·kg^-1)水稻土中14 d后Cd等重金属在蚯蚓体内的富集,以及活性氧(ROS)、抗氧化酶和氧化损伤蛋白等生化指标对Cd胁迫的响应。结果表明,与其他金属相比,蚯蚓更易吸收和富集Cd,富集系数(BSAF)可达14.68,且外源Cd浓度的增加能显著抑制(P< 0.05)蚯蚓对Ni、Cu和Zn的富集。采用饱和模型对应用梯度扩散薄膜技术(DGT)测得的土壤有效态Cd和蚯蚓体内Cd含量进行拟合,结果显示良好的相关性(r²=0.99)。Cd胁迫能诱导蚯蚓体内产生活性氧(ROS)并导致蛋白质氧化损伤,但超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽硫转移酶(GST)活性呈现先降后升的"U"型剂量效应。通过比较可知,ROS和蛋白羰基(PCO)可作为土壤Cd污染早期诊断的生物标志物,水稻土中Cd对蚯蚓产生早期伤害可能的阈值范围为0.13~0.21 μg·L^-11 DGT-Cd。     

Soil fertility in three cropping systems after conversion from conventional to organic farming

Abstract

Temporal changes in the scores of selected soil fertility indices were studied over six years in three different cases of organic crop rotation located in southern, eastern and central Norway. The cropping history and the initial scores of fertility indices prior to conversion to organic cropping differed between the sites. Crop yields, regarded as an overall, integrating fertility indicator, were in all rotations highly variable with few consistent temporal trends following the first year after conversion. On the site in eastern Norway, where conversion followed several years of all-arable crop rotations, earthworm number and biomass and soil physical properties improved, whereas the system was apparently degrading with regard to P and K trade balances and contents in soil. On the other two sites, the picture was less clear. On the southern site, which had a relatively fertile soil before conversion, the contents of soil organic matter and K decreased during the six-year period, but the scores of other fertility indices showed no trends. On the site in central Norway, there were positive trends for earthworm-related indices such as worm biomass and tubular biopores, and negative trends for soil porosity. The results, especially those from the eastern site, illustrate the general difficulty in drawing conclusions about overall fertility or sustainability when partial indicators show divergent trends. Consequently, the study gave no unambiguous support to the initial working hypothesis that organic farming increases inherent overall soil fertility, but rather showed that the effect varied among indicators and depended on status of the cases at conversion. It is concluded that indicators are probably better used as tools to learn about and improve system components than as absolute measures of sustainability.