猪场废弃物强制通风静态堆肥处理过程参数的试验研究

3种配比的通风静态堆肥试验表明：在适宜的C/N、水分、通风条件下，不同辅料和配比的堆体均能够达到设定温度55℃，并维持一定的高温期，堆肥产品的卫生学指标达到国家粪便无害化标准。通风是静态好氧堆肥的关键因素，不同原料的升温速率明显不同， 通气性能好的锯末和秸秆混合配料可在3～4 d达到设定温度，升温速率明显优于单独使用锯末配料，堆肥过程的高温和水分蒸发可明显降低堆体的含水率，堆肥后堆体体积比堆肥前减少1/2～1/3。     

不同通风量对猪粪好氧堆肥效果的影响

该文以玉米秸和稻壳混合作为调理剂进行猪粪好氧堆肥,研究不同通风量对堆肥效果的影响。试验设3个处理,通风量分别为0.5、0.3和0m3/min,通风时间根据堆体温度调整,测定了堆体温度和堆料水分、pH值、有机质含量、总氮含量和C/N。结果表明,通风能有效保证堆料升温和高温期的维持,而且能够抑制堆肥过程中堆料pH值的上升,有利于有机质的降解和C/N的降低,通风量为0.3m3/min时,综合效果较理想。结果提示,以玉米秸和稻壳混合作为调理剂,初始C/N为30︰1,含水率为62%左右时,适当通风能够满足猪粪腐熟的需要。     

城市污泥与稻草混合堆肥的最佳通风量优化研究

以城市污泥+稻草秸秆混合物料为研究对象,运用好氧堆肥方法,研究不同通风量对污泥堆肥过程的影响,测定了堆肥过程中温度、含水率、有机质含量和种子发芽指数的变化规律,分析了堆肥过程中通风与未通风之间的差异性。结果表明:(1)通风能够有效保证堆料升温和维持高温期,温度高达74.20℃,高温持续时间达到6 d,温度上升速率达到24.03℃/d。(2)通风条件下,含水率呈现先升高,后降低,然后趋于稳定的变化规律。(3)堆肥结束后,各处理有机质含量均达到国家标准。(4)通风能够显著影响种子发芽系数,各处理GI值的大小顺序为3号箱2号箱1号箱4号箱5号箱。当通风量为1.00 m~3/h,高温维持时间最长(6 d),种子发芽指数最高(84.25%),堆肥效果最理想。     

石化污泥堆肥过程中的温度层次效应及动态变化

温度是影响微生物活性的最显著因子.通过分析自然通风三角形长垄堆肥工艺处理石油化工污泥的堆体温度的层次效应及动态变化,结果表明,堆体剖面自上而下存在温度梯度,堆肥过程是好氧微生物降解有机质作用范围由上至下动态变化过程.堆肥初期,表层升温速率最快,是好氧微生物作用的主要区域.堆肥进入中、后期,次表层温度最高,成为好氧微生物作用的主要作用区域.由于核心区容重较高,整个堆肥过程中基本处于厌氧状态.不同污泥比例的堆肥对比分析表明,堆肥原料中污泥配比和高效微生物复合菌剂的投加也会对堆体的不同层次的温度变化形态具有显著影响,提高堆肥对环境变化的抵抗能力.     

通风量对蔬菜和花卉废弃物混合堆肥的影响

试验在2 m³的静态好氧堆肥中试装置中进行,以蔬菜和花卉废弃物为原料,采用0.005,0.0075和0.01 m³/(kgVS·h) 3个水平的通风量,分析了不同通风量对堆肥过程中堆体温度、有机质含量、含水率、pH值、体积等指标随时间的变化特征。通风量为0.01 m³/(kgVS·h)条件下,堆肥降解蔬菜和花卉废弃物的效果最好,其中又以堆温80℃以上的“超高温”条件下为最佳;堆体含水率均呈下降趋势,堆肥后期堆体温度和水分下降较快,不利于有机质的降解;堆体体积在堆肥初期快速下降,5 d后基本保持稳定。3个水平的通风条件下,堆体pH值、含水率变化的趋势一致,相互之间的差别不明显。     

不同调理剂对牛粪好氧堆肥的影响

养殖业的发展造成了周边环境的严重污染。好氧堆肥技术是处理固体有机废弃物的一种有效方法。该文利用自制发酵箱进行了牛粪与不同调理剂一玉米芯、玉米秸秆和稻草的混合好氧堆肥试验。试验结果表明,当堆肥底料的初始碳氮比为27:1,初始含水率为65％时,玉米芯、玉米秸杆和稻草均可作为调理剂与牛粪进行好氧堆肥,且可达到无害化要求。而采用粒径大、多孔、疏松的玉米芯作为调理剂,有利于通风供氧,堆体升温和降温均较快,高温持续时间长,堆料腐熟快,有利于加快堆肥的进程。     

不同调理剂对牛粪好氧堆肥的影响

养殖业的发展造成了周边环境的严重污染。好氧堆肥技术是处理固体有机废弃物的一种有效方法。该文利用自制发酵箱进行了牛粪与不同调理剂-玉米芯、玉米秸秆和稻草的混合好氧堆肥试验。试验结果表明，当堆肥底料的初始碳氮比为27：1，初始含水率为65%时，玉米芯、玉米秸杆和稻草均可作为调理剂与牛粪进行好氧堆肥，且可达到无害化要求。而采用粒径大、多孔、疏松的玉米芯作为调理剂，有利于通风供氧，堆体升温和降温均较快，高温持续时间长，堆料腐熟快，有利于加快堆肥的进程。     

条垛堆肥 -袋装堆肥联合处理过程中肥料性状的变化规律

条垛堆肥 -袋装堆肥联合处理可以节省厂房和占地,并免去后期翻抛设备、运行和维护费用,同时大幅度提高养殖场的粪便无害化效率,然而袋装堆肥对肥料属性的影响却不明确。本文选用人元发酵菌对牛粪和蘑菇渣先进行高温好氧堆肥处理(体积比 2︰1),待堆体经过高温期后(温度降到 50℃以下)进行袋装堆肥,待堆体温度最终与环境温度一致后,对各处理堆肥进行理化性质分析。结果表明:联合堆肥温度、NH 4+-N含-量、NH4+-N/ NO3 -N、T值、pH值、EC值、种子发芽指数均符合堆肥腐熟要求。联合堆肥显著提高了全磷含-量、全钾含量、NO 3 -N含量、EC值( P<0.05),增幅分别达到12.2%、20.0%、2177.8%、108.3%;而有机质含量、pH值显著降低( P<0.05),分别降低33.4%、6.3%;另外,联合堆肥降低了全氮含量,降幅达到 16.2%(P>0.05)。     

起爆剂促进猪粪堆肥腐熟研究

利用工厂化高温好氧堆肥方式,探究了有机肥起爆菌剂对猪粪堆肥腐熟效率的影响。通过工厂试验,以猪粪为原料,稻壳为辅料,设置对照Z1和接种起爆剂处理Z2,研究堆肥过程中不同堆体的温度、pH、EC、C/N和养分等理化指标的变化及堆体腐熟效率的差异。对照Z1与处理Z2的堆体温度在高于55℃的时间均持续了18 d以上,Z2处理的升温速率和温度最高值均高于对照Z1;两堆体的pH和EC值变化无显著差异,至堆肥结束,堆体Z1的pH稳定在7.45左右,Z2的pH稳定在7.25左右;堆体Z1和Z2的C/N分别下降了46.39%和51.33%,全碳含量分别下降了43.18%和47.34%,全氮含量分别上升了5.94%和9.28%;Z1和Z2的NH_4~+-N和NO_3~–-N具有类似的变化趋势;至第28天,Z2的发芽指数已达100%,说明肥料已完全腐熟,而Z1此时的发芽指数仅为85%;堆肥结束时,Z1和Z2的最终总养分含量(N、P2O5、K_2O)分别达51.63 g/kg和52.67 g/kg。结果表明接种有机肥起爆剂能够有效加快堆肥腐熟。     

超高温预处理装置及其促进鸡粪稻秸好氧堆肥腐熟效果

为提高畜禽粪便堆肥效率和质量,设计了一种超高温预处理好氧堆肥工艺,并以鸡粪和稻秸为原料,进行了为期62 d的堆肥试验。设置了3个处理,即:高温好氧堆肥(CK);超高温(85℃)预处理4 h+高温好氧堆肥(HPC);超高温(85℃)预处理4 h+接种0.5%新鲜鸡粪+高温好氧堆肥(I-HPC)。监测了堆体的温度、含水率、pH值等参数的变化情况,并以C/N、可溶性有机碳(dissolved organic carbon,DOC)、铵态氮、硝态氮、腐殖化指数(humification index,HI)、种子发芽指数(germination index,GI)为指标评价了堆肥腐熟度和质量。结果表明,与CK相比,超高温预处理可以提高后续堆料升温速率和最高温度、延长高温期天数、缩短堆肥周期,I-HPC、HPC的最高温度比CK分别高出13.6、12.8℃,≥50℃的天数分别比CK多3、2 d。但与HPC相比,接种新鲜鸡粪并没有加快后续堆肥进程。超高温预处理后,物料容重由0.81 g/cm~3下降为0.72 g/cm~3、pH值下降了1~2;而DOC质量分数由106 g/kg上升到124 g/kg;总挥发性脂肪酸(total volatile fatty acids,TVFAs)、NH_4~+-N质量分数分别为预处理前的3.2倍、2.45倍。HPC、I-HPC堆体有机质降解速率常数分别为0.0501、0.0534 d-1,比CK(0.00143 d-1)大,因此,HPC、I-HPC堆肥产品的TOC质量分数(182.1、192.1 g/kg)分别比CK(205.3 g/kg)低;TN质量分数(19.70、21.28 g/kg)比CK(17.96 g/kg)高;腐殖化指数(0.77、0.71)比CK(0.64)高。但HPC、I-HPC堆肥产品之间TN质量分数、腐殖化指数无显著差异。因此,超高温预处理好氧堆肥法能明显缩短堆肥周期、提高堆肥产品质量,具有较大的应用潜力。     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.     

Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater

Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Increase in auxiliary photoprotective photosynthetic pigments in wheat seedlings induced by Azospirillum brasilense

Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.     

In-situ enrichment and analysis of atrazine-degrading microbial communities using atrazine-containing porous beads

We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg⁻¹ buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg⁻¹ in conditioned and control soil, respectively. The results demonstrate that BioSep^® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.