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1.
土壤微生物量作为土壤肥力指标的探讨 总被引:34,自引:1,他引:34
对不同利用方式19个黑土样品的微生物量和养分进行了分析,结果表明林地的微生物量明显高于玉米地和大豆地,但玉米地和大豆地之间未表现出显著差异,土壤微生物量和土壤养分含量大体上都呈现出林地>大豆地>玉米地的一致的趋势;同时土壤微生物量与土壤有机质、全氮、全磷、速效钾和碱解氮呈现出显著或极显著正相关关系,分析结果还表明土壤微生物量碳作为评价土壤肥力指标比土壤微生物量氮更为灵敏。因此,土壤微生物量可以作为评价不同利用方式的黑土肥力水平的一个生物指标。 相似文献
2.
Elcio L. Balota Ines F. Yada Higo Amaral Andre S. Nakatani Richard P. Dick Mark S. Coyne 《Land Degradation \u0026amp; Development》2014,25(4):397-406
Land use choices differentially affect soil physical and biological properties. Tillage choices in particular affect soil erosion, the retention of soil organic matter, and the biological activity that organic matter supports. The present study evaluated the consequences of different cropping and tillage systems (undisturbed forest, coffee plantation, conventional, and no‐tillage row cropping) for soil microbial indicators and sulfur mineralization after 24 years of cropping on an Oxisol (Typic Haplorthox) in an experimental area at Londrina, Brazil. Soil samples were taken at 0–5, 5–10, and 10–20 cm depths and evaluated for microbial biomass P and S, S mineralization, and phosphatase and arylsulfatase activities. Land use affected microbial biomass P and S, and enzyme activity at all depths studied. The cultivated sites had lower values of microbial activity than the undisturbed forested site. Although the coffee site was not tilled and had high organic carbon content, there was low microbial activity, probably due to higher soil acidity and Al content. The estimates of pool stock for microbial P and annual P flux through the soil microbial biomass suggest that these pools are large enough to significantly affect plant nutrient availability. The greater microbial biomass and activity under forested and no‐tillage sites may be attributed, at least partially, to higher organic matter content. The soil microbial variables examined proved to be strong indicators of soil sustainability. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
小麦-玉米轮作体系不同旋耕和深耕管理对潮土微生物量碳氮与酶活性的影响 总被引:7,自引:1,他引:6
【目的】通过研究黄淮平原潮土区两年不同轮耕模式下土壤微生物量碳氮、酶活性的差异和变化特征,为该地区选择适宜的耕作制度提供理论依据。【方法】2016-2018年采用裂区设计进行田间小麦–玉米轮作系统下的轮耕试验。主处理为小麦季旋耕(RT)和深耕(DT),3个副处理为玉米季免耕(NT)、行间深松(SBR)、行内深松(SIR),共6个处理。2017、2018年玉米收获后,每10 cm一个层次,测定了0-50 cm土层土壤有机质、全氮、速效养分、微生物量碳(SMBC)、微生物量氮(SMBN)和脲酶、蔗糖酶、中性磷酸酶活性。【结果】各处理土壤有机质、全氮、速效养分、SMBC、SMBN及酶活性均随土层深度的增加而降低,40-50cm土层不受耕作方式的影响。小麦季深耕和玉米季深松对表层土壤有机质和全氮影响不明显,但显著提高了深层土壤有机质和全氮含量。小麦季旋耕显著增加了玉米季0-10 cm土层中速效养分含量,而小麦季深耕条件下的DT-SBR和DT-SIR处理则显著增加了20-40 cm土层中的速效养分含量。在0-20 cm土层,小麦季旋耕条件下的RT-NT、RT-SBR和RT-SIR处理的SMBC明显高于小麦季深耕条件下的DT-NT、DT-SBR和DT-SIR处理,但在20-40 cm土层,SMBC和SMBN均表现为小麦季深耕处理显著高于旋耕处理,且以DT-SIR处理SMBC (67.99 mg/kg)和SMBN (45.96 mg/kg)最高。小麦季深耕处理提高了深层(30-40 cm)土壤微生物量氮/全氮值,但降低了表层(0-20 cm)土壤中的微生物熵。玉米季深松处理(RT-SBR、RT-SIR、DT-SBR和DT-SIR)较免耕处理(RT-NT和DT-NT)均提高了土壤酶活性,其中,在0-20 cm土层,RT-SBR和RT-SIR处理土壤脲酶活、蔗糖酶和中性磷酸酶活性较高;而DT-SBR和DT-SIR处理则提高了深层(20-40 cm)土壤中这三种酶的活性。【结论】在本试验期内,小麦季旋耕–玉米季深松处理(RT-SBR和RT-SIR)能明显提高0-10 cm土壤速效养分含量、0-20 cm土壤微生物量碳含量,而小麦季深耕–玉米季深松处理(DT-SBR和DT-SIR)则提升了20-40 cm土层土壤有机质、全氮、速效养分、微生物量碳和氮含量;小麦季深耕处理提高了深层(30-40 cm)微生物量氮/全氮比,但降低了表层(0-20 cm)土壤微生物熵。 相似文献
4.
Jon Cotton Veronica Acosta-Martínez Jennifer Moore-Kucera Gloria Burow 《Biology and Fertility of Soils》2013,49(4):403-413
Evaluation of biofuel production cropping systems should address not only energy yields but also the impacts on soil attributes. In this study, forage sorghum (Sorghum bicolor L. Moench) cropping systems were initiated on a low organic matter soil (<0.9 %) with a history of intensively tilled low-input cotton production in the semiarid Southern High Plains of the U.S. Sorghum cropping systems were evaluated in a split-plot design with sorghum cultivar as the main plot and the combination of irrigation level (non-irrigated and deficit irrigated) and aboveground biomass removal rate (50 % and 100 %) as the split plot. The sorghum cultivars used varied in yield potential and lignin content, which are important features for feedstock-producing crops. Within 1 year, the transition from long-term cotton cropping systems to sorghum biofuel cropping systems resulted in increased soil microbial biomass C (16 %) and N (17 %) and shifts in the microbial community composition as indicated by differences in fatty acid methyl ester (FAME) profiles. Additionally, enzyme activities targeting C, N, P and S cycles increased 15–75 % (depending on the enzyme) after two growing seasons. Increased enzyme activities (16–19 %) and differences in FAME profiles were seen due to irrigation regardless of aboveground biomass removal rate. Biomass removal rate and the cultivar type had little effect on the soil microbial properties during the time frame of this study. Early results from this study suggest improvements in soil quality and the sustainability of sorghum biofuel cropping for low organic matter agricultural soils. 相似文献
5.
Smia Paiva de Oliveira Nilda Braga de Lacerda Susana Churka Blum Maria Eugenia Ortiz Escobar Tegenes Senna de Oliveira 《Land Degradation \u0026amp; Development》2015,26(1):9-21
The productivity of agricultural areas in semi‐arid regions can be improved through the use of irrigation. However, the intensive cropping of such soils can have detrimental effects, especially with regard to soil organic matter (SOM) pools. The goal of this work was to evaluate soil organic carbon and nitrogen stocks of different irrigated agricultural systems and compare these to preserved natural ecosystems adjacent to each of the cropping systems. We selected four cropping systems: banana, a maize/bean succession (MB), pasture (P) and guava (G), as well as areas covered by native vegetation. Stocks of total soil organic carbon (TOC), amounts of unprotected and protected soil organic carbon, carbon and nitrogen in microbial biomass and microbial respiration were quantified. Surface soil TOC stocks under banana, G and P grass were significantly greater than under native vegetation and MB system. The most intensive management system was the MB, and the least intensive systems were P and G. The least intensive cropping systems were grouped on the basis of similarities in TOC, POC, total soil nitrogen and N in microbial biomass stocks. These results show that the degree of soil degradation resulting from changes in land use systems increases with the intensity of the land use systems themselves. This confirms the established hypothesis that the extent of degradation of soil properties and changes in some SOM fractions depend on the intensity of soil use. Furthermore, the adoption of conservation practices may remediate soil degradation and increase SOM stocks, mainly at the soil's surface. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
6.
生物有机肥提高设施土壤生产力减缓黄瓜连作障碍的机制 总被引:9,自引:0,他引:9
7.
8.
《Soil Science and Plant Nutrition》2013,59(2):139-144
Abstract Northeast China is the main production area of maize and soybean in China. In the present study, the rates of decomposition and replacement of soil organic carbon (SOC) were estimated using the soil inventory collected since 1991 from long-term maize and soybean cultivation plots in Heilongjiang Province, Northeast China, to evaluate the sustainability of the present cultivation system. The total carbon (C) content in soil was stable without any significant changes in the plots (approximately 28.5 g C kg?1). The δ13C value of soil organic matter under continuous maize cultivation increased linearly with an annual increment of 0.07 from ?23.9 in 1991, which indicated that approximately 13% of the initial SOC was decomposed during the 13-year period of maize cultivation, with a half-life of 65 years. Slow decomposition of SOC was considered to result from the low annual mean temperature (1.5°C) and long freezing period (170–180 days year?1) in the study area. In contrast, the amount of organic C derived from maize increased in the soil with a very slow annual increment of 0.17 g C kg?1, probably because of the removal of all the plant residues from the plots. Based on the soil organic matter dynamics observed in the study plots, intentional recycling/maintenance of plant residues was proposed as a way of increasing soil fertility in maize or soybean cultivation. 相似文献
9.
Tarik Mitran Pabitra Kumar Mani Nirmalendu Basak Sunanda Biswas Biswapati Mandal 《Communications in Soil Science and Plant Analysis》2017,48(2):170-185
The present investigation was carried out in coastal Sundarbans of India to study the effects of farm yard manure, green leaf manure, and vermicompost on biological attributes of soils and yield in rice–tomato, rice–sunflower, and rice–chili cropping system over conventional farmer’s practices (control) by a strip-plot technique for the two consecutive years. The partial substitution of inorganic fertilizers through organics significantly increased the yield of various cropping systems. The use of organic materials significantly improved microbial biomass carbon, fluorescein diacetate hydrolyzing activities, dehydrogenase, and β-glucosidase activity over control, which varied in the tune of 51.6%, 67.4%, 50%, and 62.7%, respectively, due to variation in electrical conductivity (EC) of these soils. The improved soil microbial biomass and enzyme activities act as key driving factor for organic matter decomposition and nutrient transformation in organically amended soils which lead to better yield under such cropping sequences. 相似文献
10.
设施土壤微生物学特性变化研究 总被引:13,自引:0,他引:13
采用定点取样的方法,研究了不同种植年限设施土壤微生物主要类群、生物量碳和5种酶活性的变化特点,结果表明:(1)不同种植年限设施土壤微生物主要类群随季节变化不一致,细菌数量先升后降,高峰出现在6月,10月最低;真菌和放线菌数量均在3月最多,而后逐渐减少。随设施种植年限的延长,微生物总数逐渐增加,但真菌和放线菌占微生物总数的比例却呈下降趋势。与露地相比,设施栽培中真菌增加快于细菌。(2)不同种植年限设施土壤微生物生物量碳在3月和6月含量最高,随设施种植年限的延长,微生物生物量碳含量也增加。(3)不同种植年限设施土壤酶活性季节变化明显,除过氧化氢酶外,脲酶、酸性磷酸酶、中性磷酸酶和转化酶活性高峰主要出现在3月,土壤酶的总体活性随设施种植年限的延长有所下降。 相似文献
11.
Microorganisms play a key role in the response of soil ecosystems to the rising atmospheric carbon dioxide (CO2) as they mineralize organic matter and drive nutrient cycling. To assess the effects of elevated CO2 on soil microbial C and N immobilization and on soil enzyme activities, in years 8 (2006) and 9 (2007) of an open-top chamber experiment that begun in spring of 1999, soil was sampled in summer, and microbial biomass and enzyme activity related to the carbon (C), nitrogen (N) and phosphorus (P) cycling were measured. Although no effects on microbial biomass C were detected, changes in microbial biomass N and metabolic activity involving C, N and P were observed under elevated CO2. Invertase and dehydrogenase activities were significantly enhanced by different degrees of elevated CO2. Nitrifying enzyme activity was significantly (P < 0.01) increased in the August 2006 samples that received the elevated CO2 treatment, as compared to the samples that received the ambient treatment. Denitrifying enzyme activity was significantly (P < 0.04) decreased by elevated CO2 treatments in the August 2006 and June 2007 (P < 0.09) samples. β-N-acetylglucosaminidase activity was increased under elevated CO2 by 7% and 25% in June and August 2006, respectively, compared to those under ambient CO2. The results of June 2006 samples showed that acid phosphatase activity was significantly enhanced under elevated CO2. Overall, these results suggested that elevated CO2 might cause changes in the belowground C, N and P cycling in temperate forest soils. 相似文献
12.
Hari Mohan Meena R. P. Sharma 《Communications in Soil Science and Plant Analysis》2016,47(11):1430-1440
The effect of fertilizers and amendments on organic matter dynamics in an acid Alfisol was studied in a long-term field experiment initiated during 1972 at experimental farm of Department of Soil Science, CSK HPKV, Palampur (India). Continuous application of chemical fertilizers either alone or in combination with farmyard manure (FYM) or lime for 42 years significantly influenced water-soluble organic carbon (WS-OC), water-soluble carbohydrate (WS-CHO), soil microbial biomass carbon, soil microbial biomass nitrogen, soil microbial biomass phosphorus, soil microbial biomass sulfur, humic acid (HA), and fulvic acid (FA). Continuous cropping without fertilization resulted in depletion to the order of 17, 21, 24, 23, 22, 26, 12, and 18% in WS-OC, WS-CHO, microbial biomass carbon, microbial biomass nitrogen, microbial biomass phosphorus, microbial biomass sulfur, HA, and FA, respectively. Different fractions of soil organic matter were found to be positively and significantly correlated with grain and straw/stover yield of wheat and maize crops. 相似文献
13.
Soil organic carbon stocks, storage profile and microbial biomass under different crop management systems in a tropical agricultural ecosystem 总被引:3,自引:0,他引:3
We investigated the soil organic C and N stocks, storage profiles and microbial biomass as influenced by different crop management
systems in a tropical agricultural ecosystem. The different crop management systems significantly affected the C and N stocks
and microbial biomass C and N at different soil depths. Amongst the systems evaluated, the rice-wheat system maintained a
higher soil organic C content. Inclusion of legumes in the system improved the soil organic matter level and also soil microbial
biomass activity, vital for the nutrient turnover and long-term productivity of the soil. Irrespective of the cropping system,
approximately 58.4%, 25.7% and 15.9% of the C was distributed in 0–15, 15–30 and 30–60 cm depths, respectively.
Received: 10 October 1999 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2323-2337
Intensive greenhouse vegetable‐production systems commonly utilize excessive fertilizer inputs that are inconsistent with sustainable production and may affect soil quality. Soil samples were collected from 15 commercial greenhouses used for tomato production and from neighboring fields used for wheat cropping to determine the effects of intensive vegetable cultivation on soil microbial biomass and community structure. Soil total nitrogen (N) and organic‐matter contents were greater in the intensive greenhouse tomato soils than the open‐field wheat soils. Soil microbial carbon (C) contents were greater in the greenhouse soils, and soil microbial biomass N showed a similar trend but with high variation. The two cropping systems were not significantly different. Soil microbial biomass C was significantly correlated with both soil total N and soil organic matter, but the relationships among soil microbial biomass N, soil total N, and organic‐matter content were not significant. The Biolog substrate utilization potential of the soil microbial communities showed that greenhouse soils were significantly higher (by 14%) than wheat soils. Principal component (PC) analysis of soil microbial communities showed that the wheat sites were significantly correlated with PC1, whereas the greenhouse soils were variable. The results indicate that changes in soil microbiological properties may be useful indicators for the evaluation of soil degradation in intensive agricultural systems. 相似文献
15.
Yakov Kuzyakov 《Soil biology & biochemistry》2010,42(9):1363-1371
In this re-evaluation of our 10-year old paper on priming effects, I have considered the latest studies and tried to identify the most important needs for future research. Recent publications have shown that the increase or decrease in soil organic matter mineralization (measured as changes of CO2 efflux and N mineralization) actually results from interactions between living (microbial biomass) and dead organic matter. The priming effect (PE) is not an artifact of incubation studies, as sometimes supposed, but is a natural process sequence in the rhizosphere and detritusphere that is induced by pulses or continuous inputs of fresh organics. The intensity of turnover processes in such hotspots is at least one order of magnitude higher than in the bulk soil. Various prerequisites for high-quality, informative PE studies are outlined: calculating the budget of labeled and total C; investigating the dynamics of released CO2 and its sources; linking C and N dynamics with microbial biomass changes and enzyme activities; evaluating apparent and real PEs; and assessing PE sources as related to soil organic matter stabilization mechanisms. Different approaches for identifying priming, based on the assessment of more than two C sources in CO2 and microbial biomass, are proposed and methodological and statistical uncertainties in PE estimation and approaches to eliminating them are discussed. Future studies should evaluate directions and magnitude of PEs according to expected climate and land-use changes and the increased rhizodeposition under elevated CO2 as well as clarifying the ecological significance of PEs in natural and agricultural ecosystems. The conclusion is that PEs - the interactions between living and dead organic matter - should be incorporated in models of C and N dynamics, and that microbial biomass should regarded not only as a C pool but also as an active driver of C and N turnover. 相似文献
16.
Influence of agricultural land management on organic matter content,microbial activity and aggregate stability in the profiles of two Oxisols 总被引:3,自引:0,他引:3
The effects of agricultural land use on organic matter content and related soil microbial and physical properties were compared with those under undisturbed native grassland in KwaZulu-Natal, South Africa. Two separate farms situated on Oxisols were used and both contained fields with continuous long-term (>20 y) cropping histories. At site 1, soil organic C content in the surface 30 cm followed the order permanent kikuyu pasture > annual ryegrass pasture > native grassland > sugarcane > maize under conventional tillage (CT). At site 2, organic C in the surface 30 cm decreased in the order kikuyu pasture > native grassland > annual ryegrass pasture > maize under zero tillage (ZT) > maize CT. Organic C, microbial biomass C, percentage organic C present as organic C, basal respiration and aggregate stability were substantially greater in the surface 5 cm under maize ZT than maize CT but this trend tended to be reversed in the 10- to 30-cm layer. In the undisturbed sites (e.g. native grassland and kikuyu pasture) the metabolic quotient increased with depth. By contrast, under maize CT and sugarcane there was no significant stratification of organic C, yet there was a sharp decrease in the metabolic quotient with depth. Aggregate stability was high under both native grassland and kikuyu pasture and it remained high to 40 cm depth under the deep-rooted kikuyu pasture. Although soil organic C content was similar under maize CT and sugarcane, values for microbial biomass C, percentage of organic present as microbial biomass, basal respiration and aggregate stability were lower, and those for metabolic quotient and bulk density were higher, under sugarcane. This was attributed to the fallow nature of the soil in the interrows of sugarcane fields. It was concluded that the loss of organic matter, microbial activity and aggregate stability is potentially problematic under maize CT, sugarcane and annual pasture and measures that improve organic matter status should be considered. 相似文献
17.
施肥对中国农田土壤微生物群落结构与酶活性影响的整合分析 总被引:4,自引:1,他引:3
18.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2831-2847
Abstract The impact of conservation tillage, crop rotation, and cover cropping on soil‐quality indicators was evaluated in a long‐term experiment for cotton. Compared to conventional‐tillage cotton, other treatments had 3.4 to 7.7 Mg ha?1 more carbon (C) over all soil depths. The particulate organic matter C (POMc) accounts for 29 to 48 and 16 to 22% of soil organic C (SOC) for the 0‐ to 3‐and 3‐ to 6‐cm depths, respectively. Tillage had a strongth influence on POMc within the 0‐ to 3‐cm depth, but cropping intensity and cover crop did not affect POMc. A large stratification for microbial biomass was observed varing from 221 to 434 and 63 to 110 mg kg?1 within depth of 0–3 and 12–24 cm respectively. The microbial biomass is a more sensitive indicator (compared to SOC) of management impacts, showing clear effect of tillage, rotation, and cropping intensity. The no‐tillage cotton double‐cropped wheat/soybean system that combined high cropping intensity and crop rotation provided the best soil quality. 相似文献
19.
In the Lusatian mining district, rehabilitated mine soils contain substantial amounts of lignite in addition to recent carbon derived from plant litter. The aim of this study was to examine the importance of the two organic matter types as substrates for soil microbial biomass in mine soils containing organic matter with a contrasting degree of humification. Samples were taken from the lignite-containing overburden material, from a mine soil under 14-year-old black pine (Pinus nigra) and from a mine soil under 37-year-old red oak (Quercus rubra). Overburden material was ameliorated with alkaline ash and incubated in an identical manner as the 14-year-old and 37-year-old mine soils for 16 months. Carbon mineralisation was monitored throughout. After 0, 3, 6, 12 and 16 months, samples were removed and analysed for chemical parameters and for microbial biomass. In addition, 14C activity measurements in bulk soil and microbial biomass were used to estimate their lignite content.Despite the high content of organic carbon in lignite-rich overburden material, low contents of microbial biomass were recorded. Ash-amelioration led to high pH values in the overburden material, resulting in high concentrations of dissolved organic carbon most likely derived from lignite. Development of the microbial community was subsequently stimulated by presence of an easily available carbon source. In older mine soils, larger amounts of microbial biomass are most likely related to the presence of recent organic matter. Radiocarbon analysis of the microbial biomass extracted from the 14-year-old mine soil indicated higher lignite carbon contribution than recorded for microbial biomass of the 37-year-old mine soil. The highest concentration of lignite C present in microbial biomass as indicated by the Cmic/Corg ratio was, however, observed in the ameliorated overburden material. Therefore, we conclude that the importance of lignite as a carbon source for micro-organisms decreases when recent organic matter is present in the older stages of mine soil development. 相似文献
20.
D. K. Benbi H. S. Thind Shivani Sharma Kiranvir Brar A. S. Toor 《Communications in Soil Science and Plant Analysis》2017,48(15):1822-1833
Disposal of ashes from agro-industrial waste has become an important issue that can cause serious environmental problems. These materials may be used in agriculture for soil fertility improvement and carbon sequestration. The effect of applying bagasse ash (BA), rice husk ash (RHA), and RHA mixed with fly ash (MA) to wheat was evaluated on soil organic carbon (SOC) and microbial activity in a loamy sand soil after four years of wheat-rice cropping. BA application resulted in C accrual at 525 kg ha?1 y?1 in soil, whereas RHA and MA did not have a significant effect. BA increased coarse particulate (cPOC) and mineral-associated organic matter (MinOC) and extractable C pools viz. hot water soluble, potassium permanganate (KMnO4)-oxidizable, easily oxidizable, non-oxidizable, and microbial biomass C. BA application also improved overall microbial and oxidative activity and stimulated fluorescein diacetate (FDA), dehydrogenase, and cellulase enzyme activities in soil. Application of RHA though did not lead to net C sequestration, yet it increased dehydrogenase and cellulase activities. Compared to unamended soil, MA application increased MinOC and FDA activity in soil. After 4 years of their application, none of the ashes adversely influenced soil biological activity expressed in terms of enzyme activities suggesting that these ashes can be disposed to agricultural soils. However, effects of their long-term application on soil biological processes need to be further investigated. 相似文献