畜禽粪便污染及加快资源化利用探讨

本文分析了畜禽粪便的污染现状及危害、利用状况,分析了畜禽粪便污染整治及资源化利用中存在的问题,提出了加快畜禽粪便资源化利用的措施。     

粮油轮作中施肥对产量和土壤肥力的影响

采用田间定位方法连续4年研究钾肥、有机肥对产量和土壤耕层化学性质的影响,结果表明,油菜—夏玉米—冬小麦—夏玉米轮作连续4年施钾仍有显著的增产作用,玉米平均增产447kg/hm2,油菜240kg/hm2。有机肥对3种作物有显著增产作用,玉米平均增产538kg/hm2,油菜286kg/hm2,小麦353kg/hm2。夏玉米施有机肥比油菜、小麦增产显著,土娄土施有机肥土壤钾素收支基本平衡。     

塞内加尔达喀尔地区沙丘土壤中有机添加物的荧光表征及去向

The application of organic amendments on soils poor in organic matter (OM) can improve long-term soil fertility, but may also enhance the mineralization of native soil organic matter. Three organic amendments, compost, sewage sludge and horse manure used by urban market gardeners in Dakar, Senegal were analyzed for their OM maturity. Their fate was evaluated in a 45-d agronomic trial in a sandy Arenosol with lettuce. In each case, water-extractable organic matter (WEOM) and humic-like substances (HLS) were isolated from raw amendments and amended soils, and characterized using ultraviolet-visible (UV/Vis) spectroscopy. Results highlighted the general more aromatic character of HLS and WEOM fractions extracted from compost compared to the other two amendments. When applied to soils, however, these differences were not clearly observed. The aromaticity and humification degree of the labile fraction (WEOM) increased with depth in the first 30 cm for all amendments. This indicated the high lixiviation rates that fresh OM underwent in the studied sandy soil. Finally, a statistical analysis of the results was able to discriminate between surface and deeper horizons and between amended- and non-amended soil samples. Spectroscopic indices showed indeed strong increase/decrease with depth linked with the mineralization/humification processes that the fresh OM from amendments underwent during the 45 d of the agronomic trial. This study highlights the potential of spectroscopic techniques to study agricultural amendment organic matter fractions and their fate in soils.     

Effects of biochar and poultry manure on soil properties,growth, yield and quality of cocoyam (Xanthosoma sagittifolium Schott) grown in sandy soil

ABSTRACT

Field experiments were conducted during the 2017 and 2018 cropping seasons, to evaluate the effects of biochar (B) and poultry manure (PM) on soil physical and chemical properties, leaf nutrient concentrations, growth, mineral composition and corm and cormel yield of cocoyam. The experiment each year consisted of 4 × 2 factorial combinations of B (0, 10, 20 and 30 t ha^?1) and PM (0 and 7.5 t ha^?1). Results of the study indicated that in both years, the application of B and PM alone, and in combination, improved soil physical and chemical properties, leaf nutrient concentrations, growth, mineral composition and corm and cormel yield of cocoyam. There was a significant interaction effect of B and PM (B x PM) which was adduced to the ability of the B to increase PM-use efficiency and promote better use of the nutrients in the PM. It was found that combination of 30 t ha^?1 B and 7.5 t ha^?1 PM (B₃₀+ PM_7.5) gave the highest corm and cormel yield of cocoyam compared with other treatments. The combination of 30 t ha^?1 B and 7.5 t ha^?1 PM (B₃₀+ PM_7.5) exhibited the highest impact and is therefore recommended for soil sustainability and cocoyam productivity on sandy soil.     

新型有机肥的氮素在土壤中的转化及其对草莓生长和品质的影响

土壤中硝态氮和铵态氮的含量直接影响着作物的生长和品质。通过田间试验研究了不同有机肥料氮素在土壤中的转化及其对草莓生长和果实品质的影响。结果表明,施用有机肥可以提高草莓苗期土壤硝态氮的比例,硝铵比值大于尿素处理,同时有机肥处理硝铵比值从苗期至盛花期呈下降趋势,但尿素处理则表现为上升的趋势,而花序现蕾期土壤硝铵比的降低,有利于植株花蕾的形成,因此土壤硝铵比值的变化趋势一定程度上决定着草莓的产量和品质。在等量施用氮素养分的条件下,施用有机肥料均较尿素更能促进草莓生长发育和增加草莓产量。施用有机肥对草莓品质的改善作用也优于尿素,果实中糖/酸比值较无肥区提高23.7%-28.7%,较尿素区提高16.5%-21.2%。     

Influence of fertilization and organic amendments on organic‐carbon fractions in Heilu soil on the loess plateau of China

The influence of fertilization on organic‐carbon fractions separated by density and particle size in Heilu soil (Calcic Kastanozems, FAO) was investigated in a 20‐year (1979–1999) long‐term experiment on the Loess Plateau of China. Compared to an unfertilized treatment, N application alone did not increase total organic carbon (TOC) and its fractions of density and particle size. However, the treatment of N + P fertilization significantly increased salty‐solution–soluble organic carbon (SSOC), microbial biomass C (MB‐C), and organic C associated with fine silt. When manure was applied alone and in combination with N and P fertilizer, the light fraction of organic C (LFOC), SSOC, and MB‐C were increased significantly, and the TOC was as high as that of a native Heilu soil. Organic C associated with different particle‐size fractions was also increased significantly, and the allocation of C among the fractions was altered: the proportions of C in sand (>50 μm), coarse‐silt (20–50 μm), and fine‐clay (<0.2 μm) fractions were increased whereas fine‐silt (2–20 μm) and coarse‐clay (0.2–2 μm) fractions were decreased. It is concluded that N fertilizer alone is not capable of restoring organic‐matter content in the Heilu soils of the Loess Plateau and that C‐containing material like manure and straw is necessary to produce significant increase in soil organic carbon in these soils.     

猪粪堆肥臭气产生与调控的研究

通过两次室外中型堆肥试验，研究在相同水分条件(68.8%)，不同调理剂、不同碳氮比(C/N)、不同通气方式以及不同添加剂对猪粪堆肥过程中臭气产生与控制的影响。研究表明：猪粪堆肥中，臭气的主要形式是氨气，主要产生在堆肥的升温及高温期。降低堆肥的pH值、增加微生物对NH⁺₄-N的固定等是控制臭气的有效措施；过磷酸钙添加量为1.5%时，可以降低堆肥的pH值，使NH₃浓度减小，促进NH⁺₄-N向其它形式的氮转变，且不影响堆肥的腐熟；除臭剂试验组堆肥过程中臭味小，堆肥结束后的物理性状最好，不影响猪粪堆肥进程，可在生产中推广。     

Influence of liquid cattle manure on reduction processes in soil

Summary Reduction processes in cultivated soil during the decomposition of liquid cattle manure were studied in laboratory experiments. Anoxic slurries of soil and manure in different proportions or alone were followed over 5 weeks. Upon NO _inf3 ^sup- depletion, ferrous Fe appeared in solution in soil-manure slurries. Sulfide levels were generally low in the presence of both soil and manure, probably because of precipitation by Fe²⁺; Fe thereby counteracted the production of free hydrogen sulfide. Methane formation was the quantitatively most important electron sink under prolonged anoxic conditions. When extra sulfate was added to soil-manure slurries, the concentration of Fe²⁺ remained low and less methane was produced. The detection of Fe²⁺ was examined in a model system with a gel-stabilized soil-manure mixture sandwiched between two soil phases with a water content near field capacity. Large methodological problems made it impossible to quantify Fe²⁺ in this oxic-anoxic environment, but the results indicated that reducing conditions were maintained in the manure-saturated zone for the 20-day period of this experiment.     

Application of low‐phosphorus‐containing legume residues reduces extractable phosphorus in a tropical Ultisol

Application of legume green manure (GM) is suggested to be effective in increasing the availability of native soil phosphorus (P) and the dissolution and utilization of phosphate rock (PR)‐P by food crops. Experiments were conducted to study the dynamics of extractable P (P extracted by Bray‐1‐extracting solution) of an Ultisol amended with or without GM residues of contrasting P concentrations in the absence of growing plants. In two separate experiments, GM residues of Aschynomene afraspera (a flood‐tolerant legume) and of Crotalaria micans (upland) with varying P concentrations were added to an acidic soil amended with PR‐P or triple superphosphate (TSP) in plastic bottles. Soil moisture was brought to field capacity of the soil in the upland experiment and saturated with distilled water in the lowland setup. This was done to simulate aerobic upland and anaerobic lowland soil conditions in the relevant plastic bottles. Only P concentration of the residues added varied, while lignin and C : N ratios were similar. A temperature of 25°C was maintained throughout the experiment. Changes in soil extractable Bray‐1‐P were measured at the end of the incubation period (60 or 80 d). In the aerobic soils, extractable P in the combined PR+GM or TSP+GM treatments was significantly lower than in the PR‐ or TSP‐ treated soils. The amendment with GM residues alone significantly increased Bray‐1‐P over the unamended control in the case of the inorganic P‐fertilized GM residues. The trend in extractable P was similar in the soils incubated under anaerobic conditions. However, in the case of PR, concentrations of P extracted by Bray‐1 solution did not significantly change in the presence or absence of GM. The results suggest that the incorporation of GM residues with low P concentration does not lead to a net P release in upland or lowland soils. These results have implications for nutrient cycling in farming systems in W Africa as most of the soils are poor and very low in available P.