Potential of near infrared spectroscopy to determine the lipid content of untreated garbage compost

The purpose of the present study was to evaluate the capability of near infrared spectroscopy (NIRS) as a simple method to monitor the lipid content of garbage compost, which is a potential inhibitor of plant growth. We conducted a cultivation experiment with vegetable mock pak choy ( Brassica rapa L. Parachinensis Group) using two application rates of four garbage composts that differed in lipid content. The input of lipid from the compost to the field showed a significant negative correlation with germination rate and plant height in the initial growth stage. Reflectance spectra of untreated and freeze-dried and milled compost samples were taken using a scanning monochromator. Second-derivative spectra and multiple regression analysis were used to develop calibration equations for lipid and moisture contents. The calibration was carried out with the short wavelength region ([SWR] 800–1100 nm) and the long wavelength region ([LWR] 1100–2500 nm) separately. The calibration equations with the LWR were more accurate than those with the SWR for lipid and moisture determinations. The accuracies of the calibration equations for untreated samples were comparable to those for freeze-dried and milled samples. In conclusion, we suggest that the application rate of garbage compost can be determined by measuring the lipid content of untreated samples by NIRS.     

几种微生物及其组合在猪粪堆肥发酵中的作用

猪场粪便是重要污染源,但又是一类尚未充分利用的资源.研究了酵母、枯草芽孢杆菌、木霉与黑曲霉4种微生物对猪粪堆肥发酵的促进作用,并探讨几种微生物在堆肥发酵时的相互作用,同时开发出一种能令猪粪堆肥快速升温腐熟的发酵剂.结果表明,发酵剂的配比为芽孢杆菌:黑曲霉:木霉=3:2:3,酵母在升温过程中所起作用不明显.中试结果表明,用此配比的发酵剂,可以令猪粪堆肥在10d左右腐熟,并且使得堆肥产品的种子发芽指数提高21.7%.     

油茶壳基质化腐熟技术研究

为降低轻型基质育苗成本,寻找一种适合苗木生长的替代有机基质.以油茶壳为原材料,通过正交试验设计添加不同的氮源和微生物菌剂及不同的碳氮比进行油茶壳腐熟发酵试验,分析油茶壳基质理化性质的变化,结果表明:油茶壳堆沤发酵50 d可完成腐熟;腐熟后碳氮比降低,EM菌对碳氮比降低最明显,使碳氮比降到20∶1以下,其中7号处理降到1...     

Effects of compost amended lead–arsenate contaminated soils on total and inorganic arsenic concentrations in rice

Rice (Oryza sativa L.), a staple crop for over 50% of the world's population, is also a source of dietary arsenic (As) because of it's efficiencyat accumulating As. Lead–arsenate pesticide was used in agriculture, these soils potentially may be used for rice production. The objective of this study was to determine the effects of compost on total and inorganic As concentrations in rice grown on lead–arsenate contaminated soils. Three lead–arsenatesoils were amended with 10% by weight of compost and planted with rice under flooded and non-flooded conditions. Rice grain yieldwas higher with compost but not flooding. Flooding significantly increased total and inorganic As concentrations. In most cases, rice inorganic Asconcentrations were higher than the limit set by Chinaat 0.2 mg kg^?1. Compost at therate used did not reduce rice grain As to safe levels.Lead–arsenate contaminated soils are not recommended for rice production.     

Ryegrass yield and nutrient status after biochar application in two Mediterranean soils

This study was conducted to evaluate whether biochar, produced by pyrolysis at 300°C from rice husk and grape pomace (GP), affects plant growth, P uptake and nutrient status. A 3-month period of ryegrass (Lolium perenne L.) cultivation was studied on two Mediterranean agricultural soils. Treatments comprised control soils amended only with compost or biochar, and combinations of biochar plus compost, with the addition of all nutrients but P (FNoP) or without any fertilization at all (NoF). Application of both types of biochar or/with compost, in the presence of inorganic fertilization except P, significantly increased (P < 0.05) dry matter yield of ryegrass (58.9–77.6%), compared with control, in sandy loam soil, although no statistically significant increase was observed in loam soil. GP biochar and GP biochar plus compost amended loam soil harvests gave higher P uptake than control, in the presence of inorganic fertilization except P, whereas in sandy loam soil, a statistical increase was recorded only in the last harvest. In addition, Mn and Fe uptake increased with the addition of the amendments in both soils, while Ca increased only in the alkaline loam soil. Biochar addition could enhance ryegrass yield and P uptake, although inorganic fertilization along with soil condition should receive special attention.     

Effect of different organic amendments on lettuce fusarium wilt and on selected soilborne microorganisms

This study evaluated the effect of different organic amendments on lettuce fusarium wilt caused by Fusarium oxysporum f. sp. lactucae in pots under controlled conditions. Their effects on the density of the pathogen, on the total fungi and on fluorescent Pseudomonas spp. were also evaluated after two subsequent lettuce crops. A significant reduction in the severity of the symptoms of F. oxysporum f. sp. lactucae was found after the use of Brassica carinata pellets (52–79% reduction) and compost (49–67% reduction), while Brassica green manure and cattle and chicken manure only provided partial control of fusarium wilt. However, variations in effectiveness were observed for the same treatment in repeated trials. In general, an increase was observed in Pseudomonas and a decrease in fungal populations in the growing medium, which was obtained by mixing a blonde sphagnum peat and a sandy loam soil with B. carinata pellets and compost after two consecutive cropping cycles. Prolonging the Brassica and compost treatments from 30 to 60 days did not significantly affect disease severity, plant growth or the microbial population of the total fungi or Pseudomonas. The largest lettuce biomass was obtained in the non‐inoculated growing medium amended with brassica flour, chicken manure, B. carinata pellets and compost, as a consequence of fertilization. The treatment with B. juncea green manure, B. carinata (pellets and flour) and compost applied 30 days before planting led to promising results and merits further investigation for use under field conditions.     

施入城市生活垃圾堆肥对玉米植株重金属分布及土壤养分的影响

以玉米为供试作物,研究施入生活垃圾堆肥对土壤和玉米各器官重金属分布规律及对土壤养分的影响。结果表明:连续3年施肥,土壤速效养分的含量明显增加;土壤重金属呈现累积,但含量远远低于二级土壤标准(GB 15618-1995);植株中重金属含量表现为根部>茎秆>叶片>籽粒,Cd在植株根部富集,但未大量向其他部位转移,玉米植株地上部分重金属含量明显低于饲料卫生标准(GB 13078-2001)。由此推断,在短期内(3年),年施入60 000 kg·hm^-2的垃圾堆肥能提高土壤肥力,且暂时不会引起土壤重金属污染,也不影响玉米植株的饲用;使用多年后应及时监测,以保证安全性。     

Short-Time Response of Microbial Communities to Waste Compost Amendment of an Intensive Cultivated Soil in Southern Italy

In an intensely cultivated soil in southern Italy, the effects of municipal waste compost on soil activities (basal respiration, β-glucosidase, and fluorescein diacetate (FDA) hydrolysis), Biolog functional diversity, pH, and electrical conductivity (EC) were estimated in a short period following amendment. Treatment with compost at 30 t ha^?1 (dry matter) was compared to mineral fertilization and untreated soil. In these poor soils, organic amendment allowed the rapid recovery of an active and biodiverse soil community. While the addition of compost increased all microbial activities and EC, the pH did not change. Conversely, metabolic activity that was positively correlated to FDA hydrolysis rate initially was enhanced by compost but decreased with time and disappeared at the end of the incubation. Results indicated that waste compost amendments affected microbial activities, both at global and functional levels, favoring a rapid return of biological factors of fertility.     

Developing and Evaluation of Ecofriendly Fertilizer from Poultry Waste to Enhance Pulse Production in Alfisols of Semi-arid Tropics

Poultry manure (PM) has long been recognized the most desirable organic fertilizer. It improves soil fertility by adding both major and essential nutrients, as well as soil organic matter, which improves moisture and nutrient retention. The present study investigates the effectiveness of different levels of applied poultry-manure compost (PMC) and phospho-poultry-manure compost (PPMC) on the growth and yield of blackgram (Vigna mungo L). A field experiment was conducted to assess the nutrient-supplying capacity and soil health improvement potential of PMC and PPMC at 3.12, 6.25, 9.37, and 12.5 t/ha and to find the optimum dose of PMC as an organic fertilizer to maximize the pulse production in Alfisols of semi-arid tropics. Application of PPMC at 12.5 and 9.37 t ha^?1 increased the seed yield 105% and 102% more than the no-manure plot. Application of PMC at 12.5 t ha^?1 recorded 80% yield increment than no manure applied and the yield difference of PPMC was 20 to 25% greater than PMC alone. Application of PPMC at 12.5 and 9.37 t ha^?1 resulted in desirable soil physical and chemical properties especially 85 and 70% soil-available P improvement and significant role in increasing yield of blackgram. Application of PPMC at 9.37 t ha^?1 was found to be economically viable to the farmers in terms of improvement in soil properties and crop yield.     

Changes in Soil Properties and Vegetable Growth in Preparation for Organic Farming in Hawaii

Changes in soil properties and vegetable growth were quantified on a low-fertility tropical soil. Four treatments (two composts, urea, and control) were applied to an Oxisol (Rhodic Haplustox, Wahiawa series) in a field on Oahu, Hawaii. Chinese cabbage (Brassica rapa, Chinensis group) and eggplant (Solanum melongena) were grown sequentially as test crops. Soil quality as measured by hot-water-soluble carbon, dehydrogenase activity, and cation exchange capacity (CEC) increased by compost amendments. Total organic carbon or carbon dioxide (CO₂) respiration rate did not correlate with the soil amendments. Nitrogen (N) nutrition was the main factor that improved growth and carotenoid content in cabbage. The urea treatment promoted better growth in cabbage, whereas good-quality compost, made of grass clippings/tree trimmings, lime, and rock phosphate yielded better growth in eggplant, suggesting organic N requires time to mineralize and to be available to crops.