不同比例蚓粪替代化肥对设施土壤活性碳氮含量的影响

  目的  土壤微生物量碳氮（MBC、MBN）和水溶性有机碳氮（WSOC、WSON）是土壤中活跃的碳氮组分,是衡量土壤碳氮周转与养分有效性的重要指标。探究不同比例蚓粪替代化肥条件下,设施土壤微生物量碳氮、水溶性有机碳氮含量变化特征,旨在为设施土壤合理施肥提升提供科学依据。  方法  依托温室内有机肥替代部分化肥长期定位试验,以黄瓜为供试材料,试验共设6个处理,分别为100%化肥（CF100）、75%化肥（CF75）、25%蚓粪替代化肥（VM25）、50%蚓粪替代化肥（VM50）、100%蚓粪替代化肥（VM100）、不施肥（CK）。  结果  0 ~ 10 cm土层土壤活性碳氮含量略高于10 ~ 20 cm土层,其在生育期内呈先增高后降低的变化趋势。其中VM50处理提升效果最显著,较CF100处理分别提高了66.46%（0 ~ 10 cm土层）、76.02%（10 ~ 20 cm土层）;在黄瓜盛果期各处理土壤WSOC含量相对较高,VM50处理土壤WSOC含量较CF100处理分别提高22.88%（0 ~ 10 cm土层）、18.84%（10 ~ 20 cm土层）;0 ~ 10 cm土层,与CF100相比,生育前期VM25处理对土壤MBN含量提升效果较好,生育后期VM50处理对土壤MBN含量提升效果较好。10 ~ 20 cm土层,在黄瓜初果期各处理土壤WSON含量相对较高,VM50处理土壤WSON含量较CF100处理分别提高50.90%（0 ~ 10 cm土层）、12.55%（10 ~ 20 cm土层）;3种比例蚓粪替代化肥显著提高0 ~ 10 cm土层 MBC、WSOC在总有机碳,MBN、WSON在全氮中的占比,VM25、VM50处理对反映土壤微生物群落的结构信息的土壤MBC/MBN降低效果较好,VM50处理对土壤WSOC/WSON降低效果较好。  结论  在设施栽培条件下,可以通过蚓粪适量施入的措施合理替代化肥,达到给作物持续供应养分的目的,为设施栽培中科学合理施肥提供科学依据。     

牛粪对杨树人工林土壤生物学性状及其生长的影响

[目的]探讨施用牛粪对杨树人工林土壤生物学性状与生长的作用效果,为土壤培肥制度的建立及杨树人工林的合理施肥提供理论依据。[方法]通过3a大田试验,研究CK(对照,不施肥)、CF(单施化肥)、CM(牛粪)和CM+CF(牛粪和化肥各提供50%的氮)等处理对杨树人工林土壤理化特征、微生物数量、微生物量碳氮、活性有机碳、碳库管理指数(CPMI)及生长的影响。[结果]与CF处理相比,CM+CF处理显著提高了土壤中细菌数、真菌数、微生物总量和微生物量碳、氮含量,其中微生物量碳、氮含量分别较CF处理显著提高42.20%和43.75%;CM+CF处理还能明显提高土壤中碱解氮、速效磷、速效钾和交换性Mg含量,并显著降低土壤pH值。同时,CM处理使土壤总有机碳含量达最高值,而CM+CF处理使土壤的低活性、中活性、高活性有机碳含量和CPMI最高,其中CPMI分别较CK,CF和CM处理显著高出52.76,47.16,25.89。此外,CM+CF处理使杨树人工林的材积平均生长率达到45.36%,并显著高于其他处理。与CM+CF处理相比,CM处理对土壤和材积的影响效果较小。[结论]牛粪与化肥配施有助于改善杨树人工林土壤的生物学性状,有利于促进林木生长。     

蚓粪施用方式对不同品种番茄生长和土壤肥力的影响

肥料的施用方式会影响有机肥料的分解和养分释放过程,且不同作物品种在养分需求方面也各有差异。蚓粪是一种能够改善土壤和促进植物生长的新型替代肥料。采用盆栽试验研究了蚓粪施用方式对不同番茄品种生长和土壤肥力的影响,盆栽试验设置为:两个番茄品种:金棚三号和艾瑞尔;4种施肥方式:单施化肥(CF);蚓粪表施(VS),即蚓粪与盆钵上部8 cm厚土壤混施;蚓粪中施(VL),即蚓粪均匀平铺紧邻8 cm处下方;蚓粪全土混施(VM),即蚓粪与所有土壤混合。结果表明:相比全土混施,蚓粪表施和中施更能增加番茄的茎叶生物量并且促进其对氮、钾的吸收;与单施化肥相比,蚓粪的效果更依赖于施用方式,蚓粪表施和全土混施比中施更能提高土壤pH和有机碳含量。在盛花期,无论番茄品种,土壤有效磷、速效钾含量都在蚓粪表施时最高;而在收获期,蚓粪表施和全土混施的有效磷含量高于中施处理。相比蚓粪中施和全土混施,表施降低了艾瑞尔的土壤矿质氮含量。总之,蚓粪的集中施用如表施和中施,能促进番茄生长及养分吸收,并且在不同品种之间效应一致。     

Influence of Integrated Supply of Vermicompost and Zinc‐Eniched Compost with Two Graded Levels of Iron and Zinc on the Productivity of Geranium

Abstract

Two pot experiments under greenhouse condition were carried out to study the influence of vermicompost and zinc‐enriched compost with two levels of iron and zinc on the productivity of geranium (Pelargonium graveolens). Joint application of vermicompost and zinc‐enriched compost was effective in increasing the herb and oil yield over sole application of iron and zinc. Combined application of vermicompost and zinc‐enriched compost gave better herb and oil yield in both the experiments. With application of vermicompost and zinc‐enriched compost with two graded levels of iron, higher N, P, and K concentrations were observed with application of vermicompost (5 g kg^?1), vermicompost (5 g kg^?1), and Fe 12.5 ppm+Zn‐enriched compost 2.5 g kg^?1 soil, respectively, over control. Highest reduction in soil pH was observed with an application of vermicompost at 5 g kg^?1 soil; maximum soil organic carbon content was also recorded in the same treatment. In experiment II, joint application of vermicompost, zinc‐enriched compost, and graded levels of zinc recorded highest N, P, and K concentration with treatments of Zn (15 ppm)+vermicompost (2.5 g kg^?1), vermicompost (5 g kg^?1), and Zn (15 ppm)+vermicompost (2.5 g kg^?1 soil), respectively. Nitrogen, P, and K content increased by 36, 125, and 305%, respectively, with these treatments over the control.

Chemical constituents of geranium oil such as cis‐rose oxide, isomenthone, linalool, citronellyl, geranylformate, geranyl, and epi‐γ‐eudesmol were significantly improved by combined application of Zn with vermicompost and Zn‐enriched compost as compared to sole application of Zn. Similar effects were observed with Fe in combination with vermicompost and Zn‐enriched compost on most of the chemical constituents of geranium oil. Physicochemical properties of the soil were also improved as macro‐ and micronutrient availability markedly increased in both the experiments because of combined application of vermicompost and Zn‐enriched compost with two levels of Zn and Fe.     

Housefly Larvae (Musca domestica) Vermicompost on Soil Biochemical Features for a Chrysanthemum (Chrysanthemum morifolium) Farm

ABSTRACT

The housefly larvae (Musca domestica) vermireactor is capable of highly efficient waste reduction for swine manure management; however, effectiveness of larvae-vermicompost land utilization and the associated impact on soil environment are poorly understood. This study, which integrated incubation pot experiments and field plot tests on a chrysanthemum (Chrysanthemum morifolium) farm, was designed to investigate soil biochemical and microbial functions in response to inorganic fertilizer (NPK), vermicompost (VC) application, and/or combination of inorganic fertilizer and vermicompost (I + V). Pot experiments indicated that available soil nitrogen (N), phosphorus (P), and potassium (K) were significantly higher (21%-43%, 206%-306%, and 35%-36%, respectively) with VC treatment compared to NPK treatment; meanwhile, soil organic carbon (C), N and P mineralization was increased by 46%-57%, 53%-70%, and 30%-113%, respectively. Vermicompost application increased soil highly labile organic C by 19% to 42%. Vermicompost also enhanced soil enzymatic activities: 37%-68% for dehydrogenase, 22%-107% for urease, and 3.4%-56% for phosphatases, but activities of soil β-1,4-glucosidase and β-1,4-N-acetylglucosaminidase were reduced by 17%-53% and 24%-42%, respectively. Compared to pot experiment, continuous land application of vermicompost overwhelmingly caused soil nutrient accumulation, increased soil C stock and microbial biomass, enhanced soil mineralization, and improved C-, N-, and P-related enzymatic activities. Co-inertia analysis indicated that soil fertility indices positively correlated with most microbiological indices. This work reveals VC as a new biofertilizer for crop production and highlights its merit on soil health improvement.     

不同施肥措施对德州市农田土壤生物学性状的影响

[目的]探讨不同施肥措施对山东省德州市农田土壤生物学性状的作用效果,为农田土壤的培肥与农作物的合理种植提供理论依据。[方法]通过连续3a的大田试验,研究CK(对照,不施肥)、CF(尿素提供100%的氮)、CM(牛粪提供100%的氮)和CM+CF(牛粪和尿素各提供50%的氮)等处理对德州市农田土壤养分、微生物数量、微生物多样性、活性有机碳及碳库管理指数的影响。[结果]与CF处理相比,CM+CF处理显著提高了农田土壤碱解氮、速效磷、速效钾含量和部分微量元素的有效性,降低了pH值;明显增加了土壤微生物数量与微生物量碳、氮含量,其中细菌数分别较CK,CF和CM处理显著增加91.22%,65.47%和17.11%;同时,CM+CF处理的微生物多样性指数最高,并与微生物总量的变化趋势一致,而CF与CK处理的微生物多样性指数与微生物总量的变化趋势不一致。此外,CM+CF处理的低活性有机碳含量和碳库管理指数亦显著高于其他处理,其中碳库管理指数比CK,CF和CM处理高出69.52,67.84,38.61。与CM+CF处理相比,CM处理对农田土壤的影响效果较小。[结论]牛粪与化肥配施能显著改善德州市农田土壤的生物学性状,有利于提升土壤肥力和增强供肥性。     

蚯蚓粪配施化肥对玉米根际土壤生物学特征的影响

[目的]探讨蚯蚓粪与化肥配施对玉米根际土壤生物学性状的作用效果,为土壤培肥制度的建立与玉米的合理施肥提供理论依据。[方法]通过大田试验,研究CF(单施化肥)、VC(蚯蚓粪)与VC+CF(蚯蚓粪和化肥各提供50%的氮)等处理对玉米根系分泌物、根际土壤微生物数量、酶活性与腐殖质组成的影响。[结果]同CF处理相比,VC+CF处理显著提高了根系分泌物含量,并明显提高了根际土壤中微生物数量、微生物量碳含量及脲酶、蔗糖酶、过氧化氢酶、中性磷酸酶活性,其中细菌数分别较CK,CF与VC处理提高124.32%,62.99%和15.45%,脲酶活性分别高出44.27%,23.53%和12.50%。此外,VC+CF处理亦显著提高了根际土壤中胡敏酸、富里酸含量和胡/富比。同VC+CF处理相比,VC处理对玉米根际土壤生物学特征的影响较小。[结论]蚯蚓粪与化肥配施能较好地改善玉米根际区域的微生态环境。     

蚓粪替代部分化肥对温室黄瓜钾素吸收与产量的影响

【目的】设施蔬菜生产中施用蚓粪能够促进蔬菜生长发育和提高产量与品质,但施用蚓粪替代化肥的最佳比例尚需明确。【方法】以黄瓜为供试材料,以100%化肥（100%CF）处理和不施肥处理（CK）为对照,研究不同比例蚓粪（VM）部分化肥对温室黄瓜植株钾素吸收、果实产量和品质的影响。【结果】与100%化肥处理相比,减施25%化肥处理黄瓜植株钾素含量、生物量和产量并未显著降低;蚓粪替代25%化肥处理植株钾素吸收量、果实产量和品质均得到显著提升,其中产量提高14.51%,植株钾吸收量提高42.27%;蚓粪替代50%化肥处理黄瓜果实硝酸盐含量显著降低,植株钾素吸收量、生物量和产量无显著差异;100%蚓粪处理植株钾素吸收量、生物量、产量、品质均显著降低,其中产量降低了24.25%,果实可溶性固形物含量降低15.59%。【结论】在等养分条件下,蚓粪替代25%化肥,能促进植株钾素吸收,提高产量和改善品质。     

Effects of Vermicompost on Soil Physicochemical Properties and Lettuce (Lactuca sativa Var. Crispa) Yield in Greenhouse under Different Soil Water Regimes

ABSTRACT

This study mainly focused on the impacts of vermicompost (VC) treatments on physicochemical characteristics of sandy-clay-loam soil and lettuce (Lactuca sativa var. crispa) yield in a greenhouse under different soil moisture regimes. Pot experiments were conducted with different VC treatment doses (0%, 2.5%, and 5% w/w) and three soil water regimes (100%, 50%, and 25%?_f, ?_f is field capacity). Following the harvest, soil samples were taken and analyzed for physicochemical properties. The highest organic matter content (2.19%) was observed in 5% VC treatment of the full irrigation level (100%?_f) irrigation treatment and the lowest organic matter content (0.19%) was obtained from the control treatment of the lowest irrigation level (25%?_f). Soil physical properties were positively influenced by VC treatments under different irrigation regimes. The highest lettuce yield (178.7 g plant^?1) was observed in 5% VC treatment of the full irrigation level (100%?_f) irrigation treatment and the lowest lettuce yield (94.0 g plant^?1) was obtained from the control treatment of the lowest irrigation level (25%?_f). Present findings revealed that vermicompost treatments under different irrigation regimes could reliably be used to enhance soil physicochemical properties and lettuce yield.     

Relationship between soil chemical properties and microbial metabolic patterns in intensive greenhouse tomato production systems

ABSTRACT

Intensive greenhouse production involving excessive fertilizer and organic manure application rates may affect soil chemical and biological quality. Soil samples from 50 commercial greenhouses for tomato production in northern China were collected for the evaluation of the status of soil fertility and identification of the soil chemical factor that exerts the strongest influence on microbial functional diversity. The soil total nitrogen content showed high soil fertility and was 68% higher than 1000 mg kg^?1 and 14% higher than 1500 mg kg^?1. Differential soil pH values caused statistically significant shifts in microbial metabolic activity (average well color development, AWCD) and Shannon’s diversity index using Biolog^TM ECO plates assay. The highest soil microbial functional diversity was observed at near neutral pH values. When individual data points were plotted against soil organic matter (SOM), significant positive associations with soil microbial biomass nitrogen and AWCD were observed. The canonical correspondence analysis confirmed that shifts in the soil microbial functional diversity were associated with changes in pH, total nitrogen, and SOM. This study indicated that excessive fertilization changed the community-level physiological profile of the soil microorganisms, and this effect can be a consequence of changes in soil pH under intensive greenhouse management.     

施用蚯蚓粪对杨树苗根际土壤生物学特征的影响

通过盆栽试验,研究了CF(单施化肥)、VC(蚯蚓粪)和VC+CF(蚯蚓粪和化肥各提供50%的氮)处理对一年生欧美I-107杨根际土壤微生物数量、酶活性、根系建造水平及理化性状的影响。结果表明,VC+CF处理有利于协调土壤C/N比,并且化肥的施入补充了土壤中氮的消耗,从而明显提高了根际土壤中微生物数量及脲酶、过氧化氢酶、多酚氧化酶和蔗糖酶活性,其中细菌数量分别比CK,CF和VC处理提高165.99%,67.34%和31.73%,蔗糖酶活性分别提高90.37%,45.31%和32.34%。施用蚯蚓粪有利于杨树苗细根的生长,但对地上部的增长速度显著快于地下部。此外,VC+CF处理使根际土壤pH值明显降低,显著增加了根际土壤中养分离子的有效性。与VC+CF处理相比,VC处理对根际土壤生物学特征的影响较小。因此,蚯蚓粪与化肥配施更好地改善了杨树苗根际区域的微生态环境。     

Straw and optimized nitrogen fertilizer decreases phosphorus leaching risks in a long-term greenhouse soil

Purpose

Phosphorus (P) mobility in soil is controlled by its forms and soil sorption capacity. The P forms and soil sorption capacity are both affected by nitrogen (N) and carbon (C) addition. This paper aimed to (i) analyze effects of N and straw application on the different forms and content of P in the soil and its leachates in greenhouse soil, and (ii) explain variations in soil P transformation and transport in terms of contributing soil factors.

Material and methods

In this study, the impacts of N and straw application on the transformation and transport of soil P were investigated after 17 years in a greenhouse. Four fertilization regimes were implemented: farmer standard fertilization practice (CK), straw incorporation treatment (SC), optimized N fertilizer application (ON), and combined straw and optimized N fertilizer application (SN). P forms and its contents were determined in the selected leached water and its related soil samples.

Results and discussion

Compared with CK, ON treatment significantly (p < 0.05) decreased total phosphorus (P_t) and the proportion of organic phosphorus (P_o) in soil, while straw amendment did not affect soil P_t content. SC, ON, and SN all decreased soil available phosphorus (P_a) but enhanced P transformation, as evidenced by the increase in the ratio of P_a to P_t and microbial phosphorus (MBP) and alkaline phosphatases (ALP) in soil. After SN implementation, soil P adsorption capacity increased significantly and was associated with higher soil organic matter (SOM) and CaCO₃. ON showed lower P_t in the leachate than CK, but SC did not lead to significantly different. Under the SN regime, P_t loss by leaching decreased by 29.4% compared with CK and significantly reduced proportion of total dissolve P (DP_t) in leachate.

Conclusions

Our study highlights that straw and optimized N fertilizer in SN treatment not only generates lower P loss by leaching but also promotes the transformation of soil P, which were attributed to higher soil P_a in greenhouse soil. This finding further indicates that P transformation and transport in the different fertilizer regimes was primarily linked to pH and SOM in greenhouse soil.

     

Soil Properties and Maize Growth in Saline and Nonsaline Soils using Cassava‐Industrial Waste Compost and Vermicompost with or Without Earthworms

The aim of this study was to investigate the effectiveness of compost and vermicompost as soil conditioners in alleviating salt‐affected soils and increasing maize productivity. A greenhouse trial, consisting of seven soil amendment treatments in a completely randomized design with three replications, was carried out at Khon Kaen University, Thailand, during the rainy season of 2011. Plant height and total dry matter of maize increased in treatments with compost and vermicompost application when compared with the control (no fertilizer) in two types of soils (saline and nonsaline) during the growing season. Soil pH and electrical conductivity in saturation paste extracts were decreased by compost and vermicompost amendments with or without earthworms when compared with unamended treatments in the saline soil. Compost and vermicompost amendments improved cation exchange capacity, soil organic carbon, total nitrogen and extractable phosphorus in both soils. These amendments also increased exchangeable K⁺, Ca²⁺ and Mg²⁺ while decreasing exchangeable Na⁺ in the saline soil, which suggested that Ca²⁺ was exchanged for Na⁺, exchangeable Na⁺, then leached out, and soil salinity reduced as a result. Soil microbial activities including microbial C and N and basal soil respiration were improved by the application of compost and vermicompost amendments with or without earthworms when compared with the control in both soils. This experiment showed that the compost and vermicompost were effective in alleviating salinity and improving crop growth. Copyright © 2013 John Wiley & Sons, Ltd.     

Effect of different application rates of organic fertilizer on soil enzyme activity and microbial population

Abstract

After cultivating 24 crops of vegetables for three consecutive years in a greenhouse, the effects of different application rates of compost (Rate 1, 270 kg N ha^?1 y^?1; Rate 2, 540 kg N ha^?1 y^?1; Rate 3, 810 kg N ha^?1 y^?1; Rate 4, 1,080 kg N ha^?1 y^?1) were compared with the effects of chemical fertilizer (CF) and no application of fertilizer treatments (CK) for some selected soil chemical properties, microbial populations and soil enzyme activities (dehydrogenase, cellulase, β-glucosidase, protease, urease, arysulphatase, and acid and alkaline phosphatases). The results show that the pH, electrical conductivity, concentrations of total nitrogen (N) and the organic matter received from compost treatment were generally higher than those received through CF treatment. The soil microbial biomass, populations of bacteria, fungi and actinomycetes, as well as soil enzyme activities increased significantly in the compost-treated soils compared with the CF-treated soil. In most instances, no significant increase was observed in the enzymatic activities studied for compost applications higher than a Rate 2 treatment. However, all enzymatic activities examined showed significant linear correlations with the organic matter contents of the soils. The vegetable yield reached its highest level at the Rate 2 treatment and declined or leveled off in the higher treatments, implying that a high application rate of compost cannot further increase the crop yield after the soil fertility has been established. High organic matter content in the soil was found to alleviate the adverse effect of soluble salts on vegetable growth. In conclusion, an application rate of compost at Rate 2, 540 kg N ha^?1 y^?1, is adequate on the basis of vegetable yields and soil chemical, biochemical and enzymatic properties in greenhouse cultivation under subtropical climatic conditions.     

Phyllostachys edulis (moso bamboo) rhizosphere increasing soil microbial activity rather than biomass

Purpose

Rhizosphere and fertilization might affect soil microbial activities, biomass, and community. This study aimed to evaluate the impacts of Phyllostachys edulis (moso bamboo) rhizospheres on soil nutrient contents and microbial properties in a moso bamboo forest with different fertilizer applications and to link soil microbial activities with abiotic and biotic factors.

Materials and methods

The experiment included three treatments: (1) application of 45% slag fertilizer (45%-SF); (2) application of special compound fertilizer for bamboos (SCF); and (3) the control without any fertilizer application (CK). Simultaneously, bulk soils and 0.5, 2.5, 4.5, and 6.5-year-old (y) bamboo rhizosphere soils were selected. Soil nutrient contents were analyzed. Microbial activities were evaluated based on the activities of soil enzymes including β-glucosidase, urease, protease, phosphatase, and catalase. The total microbial biomass and community were assessed with the phospholipid fatty acids (PLFAs) method.

Results and discussion

In the CK and SCF treatments, organic matter contents of rhizosphere soils were significantly higher than those of bulk soils. Soil β-glucosidase, urease, protease, phosphatase, and catalase activities in rhizosphere soils were higher than those of bulk soils, with the sole exception of β-glucosidase of 0.5 y rhizosphere soil in the 45%-SF treatment. Compared with the CK treatment, fertilizer applications tended to increase soil total PLFAs contents and changed soil microbial community. Moso bamboo rhizospheres did not significantly increase the total microbial biomass. In the SCF treatment, the Shannon index of bulk soil was significantly lower than those of rhizosphere soils.

Conclusions

Our results suggested that both rhizospheres and fertilizer applications could change the soil microbial community structures and that moso bamboo rhizosphere could increase microbial activity rather than biomass in the forest soils with different fertilizer applications.

     

有机物料施用对旱地红壤作物产量和有机质活性组分的影响

为了探讨不同有机物料施用对作物产量和土壤有机质活性组分的影响,以达到农田增产和土壤培肥的目的,本研究依托2015年在江西省红壤研究所布置的田间施肥试验,设置不施肥(CK)、常量化肥(CF)、减量化肥(RF)、减量化肥配施秸秆(RFR)、减量化肥配施生物黑炭(RFB)、减量化肥配施猪粪(RFP)、减量化肥配施蚓粪(RFV)7种不同施肥处理,研究减量化肥40%条件下配施不同有机物料对作物产量及耕层土壤有机质活性组分的影响。结果表明:在红薯-油菜轮作制度下,减肥配施有机物料处理的作物产量较常量化肥处理都有不同程度的增加,其中RFP、RFV处理油菜籽产量显著高于CF处理(P0.05);减肥配施有机物料处理的土壤微生物生物量有机质(MBOM)、水溶性有机质(DOM)、颗粒性有机质(POM)、易氧化有机质(LOM)含量均高于CF处理,其中油菜季POM含量较红薯季有明显的提升;相关性分析表明,经过两季的施肥处理,SOM和有机质活性组分与作物产量均呈显著正相关关系(P0.05),MBOM、POM、LOM与SOM呈极显著正相关性(P0.01)。可见,不同有机物料替代部分化肥,可以一定程度提高作物产量,更重要的是可以促进土壤有机质活性组分的提高,对于土壤培肥至关重要。     

Effects of Food Waste Compost on Soil Microbial Populations,Tomato Yield,and Tomato Quality

A pot experiment was conducted to investigate the effects of food waste compost (FW) on soil microbial population and growth, fruit yield, and quality of tomato grown in a greenhouse compared to no fertilizer (CK), chemical fertilizer (CF), decomposed chicken manure (CM), pig manure (PM), horse manure (HM), and bull manure (BM). Results show that FW treatment had the greatest numbers of bacteria, fungi, and actinomycetes in soils and shoot biomass, fruit diameter, and fruit yield of tomato, and it increased fruit yield by 12.6, 28.5, 31.0, and 40.0% when compared to HM, CF, CM, and CK, respectively. The FW treatment also improved fruit quality, with the contents of vitamin C, soluble sugar, and organic acid and the sugar/acid ratio of 22.8 mg 100 g^?1, 3.84%, 0.50%, and 7.73, respectively. Thus food waste compost can be as an alternative to chemical fertilizer and other animal manures in vegetable cultivation.     

蚯蚓粪与土壤复配比例对基质微生物性状及韭菜生长和品质的影响

【目的】蚯蚓粪是蚯蚓消化有机废弃物产生的均匀颗粒,能够提升土壤肥力,改良土壤结构并促进作物生长。本文初探了蚯蚓粪与土壤的不同配比对基质微生物性状及韭菜生长和品质的影响,为蚯蚓粪的开发利用提供依据。 【方法】2015年4—6月在中国农业大学温室内进行盆栽试验,按蚯蚓粪、土壤质量比 (w/w) 设置4个处理,依次为:0/100% (纯土壤不添加蚯蚓粪,CK);20%/80% (T1);60%/40% (T2);100%/0 (T3)。韭菜收获后,测定了基质养分含量、微生物群落变化、韭菜生物量、可溶性蛋白总量、可溶性糖总量和叶绿素含量。 【结果】1) 随着蚯蚓粪添加比例的增加,基质中的全氮、速效钾和有机质的含量均显著提高;2)蚯蚓粪能显著促进韭菜根系生长,并改善韭菜品质。与对照相比,T1、T2和T3处理中韭菜新根比分别提高5.75%、6.39% 和22.23%;韭菜可溶性蛋白总量提升了1.84～5.97倍,可溶性糖总量提升了1.49～1.60倍 (P < 0.05);3)蚯蚓粪能显著提高基质中的细菌和真菌多样性,并显著增加细菌116、118、130、226、297片段 (P < 0.05),但减少了真菌71、91、153、351片段 (P < 0.05)。 【结论】蚯蚓粪改善了基质的微生物群落结构,提高细菌和真菌的多样性,增加养分有效性,进而促进韭菜生长并改善韭菜品质。蚯蚓粪直接用作基质的效果最好,但从经济角度考虑,蚯蚓粪与土壤按质量百分比20%/80%即可基本达到满意的效果。     

Changes in nutrient content,enzymatic activities and microbial properties of lateritic soil due to application of different vermicomposts: a comparative study of ergosterol and chitin to determine fungal biomass in soil

In this experiment, vermicomposts, prepared from five different waste materials, were applied to acid lateritic soil under field conditions and soil samples were collected after 90 days to study the effect of vermicomposts on different chemical and biochemical. Results suggest that vermicompost prepared from paddy straw is most effective to improve nutrient content, enzymatic activities and microbial properties of lateritic soil. Vermicompost application significantly (P ≤ 0.05) increased the concentration of organic C, mineralizable N, available P and exchangeable K in soil. Amylase, protease, urease and acid phosphatase activities were also significantly (P ≤ 0.05) higher in vermicompost treated soils compared with the control. Both basal and substrate‐induced microbial respiration, microbial biomass C and N and fungal population in lateritic soil were increased due to vermicompost application. Ergosterol and chitin content were significantly (P ≤ 0.05) higher in vermicompost treated soils over the control. Application of vermicompost increased the proportion of fungal biomass in total soil microorganisms.     

Surface mulching and a sandy soil interlayer suppress upward enrichment of salt ions in salt-contaminated field

Purpose

The suppression effect of a sandy soil interlayer on topsoil enrichment of salt ions was investigated. However, whether this suppression effect was enhanced by surface mulching was little documented. The objectives of this study were to compare the suppression effects under different materials mulching, and to investigate an innovative method to suppress the soil salt ions down-to-top enrichment.

Materials and methods

In this study, the sandy soil layer was pre-positioned at 60–100 cm depth in a salt-contaminated site in advance, achieving the suppression effect on surface enrichment of salt components as expected. Three treatments were herein designed as bare field (CK), plastic film mulching (PM), and maize straw mulching (SM) to examine the dynamics of water and salt movement across soil profiles during the summer with strong evaporation.

Results and discussions

Results showed that total salt content was increased by 21.3 and 8.0% in CK and SM respectively, while decreased by 24.9% in PM at the end of strong evaporation period, comparing with the beginning. Thus, surface mulching further strengthened this suppression effect, but PM displayed better performance than SM did. The data also demonstrated that vertical transport of soil water was much restrained in PM and SM, accordingly inhibiting upward transfer of salt ions. Particularly, sodium adsorption ratio (SAR) ranged from 14.3–265.7, 17.9–147.1, 38.4–147.2 mmol^1/2 kg^?1/2 at a shallow soil layer (0–60 cm) in CK, PM, and SM, respectively.

Conclusions

The results suggested that sandy soil interlayer settings with plastic mulching are a critical technical strategy for salt-contaminated land reutilization and management.