Effect of sulfur and composted manure on SO4-S,P and micronutrient availability in a calcareous saline–sodic soil

A factorial design with different levels of elemental S and cow manure was used to investigate the effects of S and manure on SO₄-S, P and micronutrient availability in a calcareous saline–sodic soil. The results revealed that the recovery of SO₄-S increased significantly (p≤0.05) in all treatments as elemental S increased, particularly when in combination with manure. The interactional effects of S° and manure application rates resulted in a decrease in soil pH of 0.1 to 0.9 units and increases in soil EC from 0.1 to 2.6 dS m^?1 as result of an increase in the number of oxidisers and the oxidation rate of elemental S. Application of S° in combination with manure led to an increase in soil-available-P (0.6–40 mg kg^?1), DTPA-Zn (0.2–3.9 mg kg^?1) and DTPA-Fe (0.1–5.6 mg kg^?1).     

Herbicides interactions with cow manure and field soil organic matter

The direct interaction of the herbicide metazachlor ‐chosen as an example‐ with the soil organic matter has been studied by laboratory incubation of old and young cow manures containing metazachlor. The extraction efficiencies of solvents of increasing polarities indicated the formation of association compounds by bonds weaker than covalent between metazachlor and the organic matter: electron donor‐acceptor complexes, hydrogen bonding complexes, and complexes by both bonding types. Laboratory incubation of metazachlor in soil of low organic matter content indicated that the soil mineral part only had a diluting effect on the soil organic matter capacity to adsorb metazachlor. Similar association compounds were observed in the soil of a cauliflower field crop. Their concentrations were greater in the plots treated with organic fertilizers than in the organic fertilizers untreated plots. The free‐ unbound metazachlor was faster metabolized than the one bound to the soil organic matter, explaining why the organic fertilizer treatments slow down the herbicide soil biodegradation during the main first crop period. Inclusion of metazachlor in the field soil humic acids lattice ‐another kind of herbicide association compound with the soil organic matter‐ occurred at crop end when most of the metazachlor was metabolized; the soil concentrations of this kind of association compound thus was low, so that the release after crop of metazachlor in the environment has no practical significance.     

佛山市畜禽粪便排放量与农田负荷量分析

在确定畜禽粪便年排放量的估算方法和畜禽粪便排泄系数的基础上,根据2009年佛山市畜禽养殖数据,估算佛山市畜禽粪便产生量及其主要养分含量,并对畜禽粪便的环境效应进行评价。结果表明,2009年佛山市畜禽粪便总排放量约为332.35万t,其中以商品肉猪和鸡排放量较高,分别占总量的60.85%和14.10%。畜禽粪便中COD、BOD、NH3-N、TP和TN含量分别为97 004.17、92 782.79、7 929.77、7 850.56和18 382.88 t。农田畜禽粪便负荷量（以猪粪当量计）为74.07 t.hm-2,N、P养分负荷量分别为436.83和186.55 kg.hm-2,畜禽粪便产生的环境问题已不容忽视。     

有机肥中重金属特征及其控制技术研究进展

随着工业的快速发展,农药、肥料及地膜等系列农用化学物质的广泛使用,农田土壤重金属污染越来越严重。重金属进入土壤后,其难移动性导致大量积累,造成土壤环境污染,影响植物生长,危及人类的健康。有机肥是我国农业生产中非常重要的肥料,其来源也十分广泛。施用有机肥是提高作物产量的必要措施,同时也是土壤重金属的主要输入途径之一,研究有机肥的重金属特征及其有关控制技术对农产品安全和有机废弃物的再利用具有重要意义。文章就畜禽排泄物堆肥、污泥堆肥、生活垃圾堆肥和沼肥等主要有机肥料的重金属来源、含量以及不同溯源有机肥料对土壤中重金属有效性的影响进行综述,重点介绍了畜禽排泄物堆肥中重金属含量和饲料添加剂之间的关系,为农田土壤重金属污染防治和农产品安全提供科学依据。除从有机肥的源头控制重金属外,文章主要介绍了化学法、生物吸附法、生物淋滤法和电化学法等重金属控制技术,针对各种控制方法,阐述了其原理、应用实例、优缺点及研究进展情况,提出了解决有机肥重金属污染问题的思路和方法,为有机肥料的资源化利用提供了参考。最后指出,为了实现养殖业与种植业的安全链接,除选用重金属含量低的有机肥,通过相关技术有效控制有机肥中的重金属外,还要注重肥料用量、施肥时间、施肥技术的合理选择,从最大程度上避免有机肥料给作物和人类带来的副作用。     

牛粪生物炭对磷的吸附特性及其影响因素研究

以牛粪生物炭为吸附剂,采用平衡吸附法研究了牛粪生物炭对磷的吸附特征.研究了pH值、共存离子、反应温度、投加量、热解温度等对牛粪生物炭吸附磷的影响.结果表明,牛粪生物炭吸附磷的最佳初始pH值为7.0;共存离子的存在对生物炭吸附磷的影响有限;反应温度升高不利于磷的吸附;当投加量为0.1g时,对磷的去除率较为理想;热解温度升高不利于对磷的吸附.通过对实验数据进行动力学、吸附等温线及热力学分析,发现牛粪生物炭对磷的吸附动力学数据符合拟二级吸附动力学方程,Langmuir-Freundlich(R2=0.9705)和Temkin(R2=0.9556)方程能很好地描述磷在牛粪生物炭上的吸附行为.热力学分析结果显示25,35,45℃下的吉布斯自由能变化(ΔG0)分别为-17.43,-15.98,-15.89kJ/mol,表明牛粪生物炭对磷的吸附是自发的过程.     

不同原料厌氧发酵及其微生物种群的研究

使用PCR-DGGE技术,对以鸡粪、猪粪、牛粪、秸秆为发酵原料的发酵体系的微生物群落多样性进行了研究.在发酵不同时间取样,进行了日产甲烷量、日产甲烷浓度的变化分析和DGGE分析.结果表明,日产甲烷量整体趋势为猪粪>鸡粪>秸秆>牛粪,日平均产甲烷量分别为2.67、2.24、0.99、0.49L;猪粪、鸡粪、秸秆的日产甲烷浓度在整个发酵周期大多可维持在50%以上,牛粪的日产甲烷浓度大部分时间低于30%;细菌的优势菌群有拟杆菌属(Bacteroidetes)、密螺旋体属(Treponema)、厌氧绳菌科(Anaerolineaceae)等,新增优势菌群有梭菌属(Clostridium)、脱硫叶菌属(Desulfobulbus)、毛螺旋菌科(Lachnospiraceae)、醋弧菌属(Acetivibrio);古菌的优势菌群有甲烷鬃菌属(Methanosaeta)、甲烷八叠球菌属(Methanosarcina)、甲烷八叠球菌目(Methanosarcinales),新增优势菌群有斯氏甲烷球菌属(Methanosphaera stadtmanae).     

猪粪及奶牛粪中温厌氧发酵对Cu和Zn的影响

以猪粪和奶牛粪为发酵原料,在中温〔(37±2)℃〕条件下采用完全混合式厌氧反应器进行了158 d的室内试验研究,分析厌氧发酵过程中Cu和Zn在沼液中质量浓度的变化及其在沼渣中的赋存形态. 结果表明:①猪粪沼液中ρ(TCu)和ρ(TZn)(TCu和TZn分别为总Cu和总Zn)随发酵时间的增加逐渐升高,而奶牛粪沼液中二者变幅不明显. ②整个发酵过程中,猪粪沼液中ρ(TCu)和ρ(TZn)的平均值极显著低于进料(P<0.001),降幅分别为80%和43%;而奶牛粪沼液中二者降幅分别仅为11%和13%. ③猪粪和奶牛粪沼液中ρ(溶解性Cu)占ρ(TCu)的53%和43%,与进料相比有小幅降低;而猪粪和奶牛粪沼液中ρ(溶解性Zn)占ρ(TZn)的35%和19%,极显著高于进料(P≤0.01),增幅分别为109%和37%. ④猪粪和奶牛粪沼渣中Cu主要以可氧化态存在,Zn主要以残渣态和酸溶态/可交换态存在. 中温厌氧发酵对猪粪和奶牛粪中溶解性Cu和Zn的削减效果有限,并且沼渣中残渣态Cu和Zn的减少可能增加二者的生物有效性,因此不利于农田的直接利用.      

Mesophilic and thermophilic anaerobic digestion of swine manure with sulfamethoxazole and norfloxacin: Dynamics of microbial communities and evolution of resistance genes

• SMX addition had negative effect on acetoclastic methanogens in mesophilic AD. • Thermophilic AD was more effective in eliminating resistance genes than mesophilic. • ARGs variations in AD were mainly affected by succession of microbial community. • Methane production was significant associated to ARGs reduction. The role of norfloxacin (NOR) and sulfamethoxazole (SMX) in mesophilic and thermophilic anaerobic digestion (AD) of pig manure, with respect to methane production and variations in the microbial community and resistance genes, including antibiotic resistance genes (ARGs), class I integrase (intI1), and heavy metal resistance genes (MRGs), was investigated. The results indicated that NOR exerted little influence on the microbial community, whereas SMX negatively affected the acetoclastic methanogens. The abundance of two sulfonamide resistance genes (sul1 and sul2), three quinolone resistance genes (qnrS, parC, and aac(6’)-Ib-cr), and intI1 decreased by 2‒3 orders of magnitude at the end of thermophilic AD. In contrast, mesophilic AD was generally ineffective in reducing the abundance of resistance genes. According to the results of redundancy analysis, the abundance of ARGs was affected primarily by microbial community dynamics (68.5%), rather than the selective pressure due to antibiotic addition (13.3%). Horizontal gene transfer (HGT) through intI1 contributed to 26.4% of the ARG variation. The archaeal community also influenced the changes in the resistance genes, and ARG reduction was significantly correlated with enhanced methane production. Thermophilic AD presented a higher methane production potential and greater reduction in resistance gene abundance.     

基于CSTR反应器鸡粪秸秆共消化产甲烷特性及菌群变化研究

基于实际工程通过控制有机负荷对不同配比鸡粪和玉米秸秆 （VS比分别为1：0、5：2、1：1）进行联合厌氧消化,分析了不同VS比变化对水解酶活性及微生物动态群落变化的影响,并确定了鸡粪秸秆联合厌氧消化的最优配比.结果表明,当VS比为1：1时,碳氮比 （C/N）为17,此时甲烷日产量峰值为31.46 L,累计产甲烷量为940.96 L,产甲烷效果最好,为最优配比;对比3组实验秸秆表面结构降解情况,C3 （VS比=1：1）组各水解酶活性均高于C1 （VS比=1：0）和C2 （VS比=5：2）组,且Megasphaera和Bacteroides作为纤维素酶主要分泌菌属相对丰度较高,纤维素酶活性峰值达到258.94 U·mL^-1,使秸秆中的纤维素和木质素得到有效降解;秸秆含量增加提高了水解细菌多样性,降低了古菌多样性,Lactobacillus属于Bacteroidetes门,由于其具有较好的抗逆性在C2和C3组丰度较高,能够作为水解产酸阶段的优势菌属;C3组产甲烷古菌丰度变化较为稳定,在实验中期以食氢产甲烷菌为主,优势菌属主要有Methanosphaera和Methanobrevibacter,实验后期以食乙酸产甲烷菌为主,优势菌属主要为Methanosaeta、Methanospirillum和Methanoregula.     

有机无机肥料对农业环境影响述评

论述了有机肥在中国的使用情况和对农业生产的作用、化肥对农产品质量的影响、化肥对土壤肥力的贡献、有机肥和化肥对大气环境和水体的影响。目前人们在对化肥使用的认识上普遍存在误区,认为施用化肥一定会对环境产生污染,只有使用有机肥才能解决问题。中国是一个人口大国,今后在一个相当长的时间内,农业产品的生产在养分的投入上仍然需要以化肥为主,充分、合理、平衡的化肥投入不仅能满足人们对农产品数量上的需要,而且一定能满足人们对农产品品质的要求。化肥的合理施用可以改善和提高农产品品质,提高土壤有机质含量,改善土壤理化性质,减少温室气体的排放和水体污染。化肥本身是无害的,有害的是对化肥的不合理施用。在肥料问题上,今后需要关注 的应该是生产和使用更优质、更高效的化肥,推广科学合理的施肥技术,提高化肥的利用效率。