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Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region
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作者 Fatma Selcen Sakar Gürcan Güleryüz 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期213-228,共16页
In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest ... In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest communities.In the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 year.Sampling locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest communities.F.orientalis had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),P.nigra the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N turnover.Tannic acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification. 展开更多
关键词 Oldest forest communities nitrogen mineralization NITRIFICATION Tannic acid Total phenolic LITTER
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Effects of nitrogen and phosphorus additions on soil microbial community structure and ecological processes in the farmland of Chinese Loess Plateau 被引量:1
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作者 KOU Zhaoyang LI Chunyue +5 位作者 CHANG Shun MIAO Yu ZHANG Wenting LI Qianxue DANG Tinghui WANG Yi 《Journal of Arid Land》 SCIE CSCD 2023年第8期960-974,共15页
Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namel... Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namely nitrogen(N)and phosphorus(P).Nevertheless,the specific mechanisms governing the influence of soil microbial community structure and ecological processes in ecologically vulnerable and delicate semi-arid loess agroecosystems remain inadequately understood.Therefore,we explored the effects of different N and P additions on soil microbial community structure and its associated ecological processes in the farmland of Chinese Loess Plateau based on a 36-a long-term experiment.Nine fertilization treatments with complete interactions of high,medium,and low N and P gradients were set up.Soil physical and chemical properties,along with the microbial community structure were measured in this study.Additionally,relevant ecological processes such as microbial biomass,respiration,N mineralization,and enzyme activity were quantified.To elucidate the relationships between these variables,we examined correlation-mediated processes using statistical techniques,including redundancy analysis(RDA)and structural equation modeling(SEM).The results showed that the addition of N alone had a detrimental effect on soil microbial biomass,mineralized N accumulation,andβ-1,4-glucosidase activity.Conversely,the addition of P exhibited an opposing effect,leading to positive influences on these soil parameters.The interactive addition of N and P significantly changed the microbial community structure,increasing microbial activity(microbial biomass and soil respiration),but decreasing the accumulation of mineralized N.Among them,N24P12 treatment showed the greatest increase in the soil nutrient content and respiration.N12P12 treatment increased the overall enzyme activity and total phospholipid fatty acid(PLFA)content by 70.93%.N and P nutrient contents of the soil dominate the microbial community structure and the corresponding changes in hydrolytic enzymes.Soil microbial biomass,respiration,and overall enzyme activity are driven by mineralized N.Our study provides a theoretical basis for exploring energy conversion processes of soil microbial community and environmental sustainability under long-term N and P additions in semi-arid loess areas. 展开更多
关键词 nitrogen and phosphorus additions microbial community structure farmland ecosystem nitrogen mineralization soil enzyme activity
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Spatial distribution and driving factors of sediment net nitrogen mineralization in riparian zone of the Three Gorges Reservoir
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作者 JIA Kai-tao HE Li-ping +4 位作者 WANG Ke-hong YU Zhi-guo LIANG Li-jiao YU Zhuo-lin LIN Jun-jie 《Journal of Mountain Science》 SCIE CSCD 2023年第2期381-390,共10页
Inorganic nitrogen(N)loss through sediment N mineralization is important for eutrophication surrounding riparian zone.Sediment physicochemical properties have been changed at water-level elevation in riparian zone of ... Inorganic nitrogen(N)loss through sediment N mineralization is important for eutrophication surrounding riparian zone.Sediment physicochemical properties have been changed at water-level elevation in riparian zone of the Three Gorges Reservoir(TGR)due to differences in hydrological stress and human activity intensity.However,spatial distribution and driving factor of net N mineralization rate(Nmin)and its temperature sensitivity(Q10)based on the changes in sediment physicochemical properties are still unclear at waterlevel elevation in the riparian zone.A total of 132 sediment samples in the riparian zone were collected including 11 transections and 12 water-level elevations on basin scale of the TGR during drying period,to conduct a 28-day incubation at 15℃,22℃,29℃and 36℃.Nmin,total N(TN)and substrate quality(SQ)increased with water-level elevation,while Q10 showed an opposite trend(P<0.001).Results of the structural equation model showed that water-level elevation had direct positive effects on TN and SQ(P<0.01).In addition,TN was the major factor that had a direct positive effect on Nmin,and SQ was the crucial factor that had a direct negative effect on Q10(P<0.001).In conclusion,increases in TN and SQ were major driving factors of Nmin and its Q10 at water-level elevation,respectively,in riparian zone of the TGR during drying period. 展开更多
关键词 Inorganic nitrogen loss Sediment physicochemical properties Drying period Substrate quality Net nitrogen mineralization rate Temperature sensitivity
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Effects of Temperature and Nitrogen Input on Nitrogen Mineralization in Alpine Soils on Tibetan Plateau 被引量:4
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作者 白洁冰 徐兴良 +3 位作者 付刚 宋明华 何永涛 蒋婧 《Agricultural Science & Technology》 CAS 2011年第12期1909-1912,共4页
[Objective] The study aimed to investigate the effects of temperature and nitrogen input on nitrogen mineralization in alpine soils on the Tibetan Plateau.[Method]An incubation experiment in the laboratory was conduct... [Objective] The study aimed to investigate the effects of temperature and nitrogen input on nitrogen mineralization in alpine soils on the Tibetan Plateau.[Method]An incubation experiment in the laboratory was conducted using three alpine soils.These soils were collected from the top 10 cm depth in three grassland types:alpine meadow in Haibei,alpine steppe in Naqu and alpine wetland in Dangxiong.[Result] Temperature significantly affected nitrogen mineralization in alpine soils of three grassland types.The mineralization rate in alpine steppe soil rose with the rise of temperature,while the mineralization rate in the alpine meadow soil and alpine wetland soil decreased with the rise of temperature.Nitrogen input had no significant effect on nitrogen mineralization in the alpine meadow soil,but significantly increased nitrogen mineralization in the alpine steppe soil and the alpine wetland soil.Grassland types significantly affected nitrogen mineralization in alpine grasslands.[Conclusion] The effects of temperature and nitrogen input on nitrogen mineralization in alpine soils on the Tibetan Plateau were significant.And those different effects depended on different types of grassland. 展开更多
关键词 nitrogen mineralization TEMPERATURE nitrogen input Alpine grassland Tibetan Plateau
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Review of study on mineralization, saturation and cycle of Nitrogen in forest ecosystems 被引量:4
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作者 杨金艳 范晶 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期239-243,共5页
Nitrogen is one of the most important elements that can limit plant growth in forest ecosystems. Studies of nitrogen mineralization, nitrogen saturation and nitrogen cycle in forest ecosystems is very necessary for un... Nitrogen is one of the most important elements that can limit plant growth in forest ecosystems. Studies of nitrogen mineralization, nitrogen saturation and nitrogen cycle in forest ecosystems is very necessary for understanding the productivity of stand, nutrient cycle and turnover of nitrogen of forest ecosystems. Based on comparison and analysis of domestic and in-ternational academic references related to studies on nitrogen mineralization, nitrogen saturation and nitrogen cycle in recent 10 years, the current situation and development of the study on these aspects, and the problems existed in current researches were reviewed. At last, some advices were given for future researches. 展开更多
关键词 nitrogen nitrogen mineralization nitrogen saturation Climate change nitrogen cycling
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Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen
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作者 马洪波 许仙菊 +3 位作者 宁运旺 汪吉东 张辉 张永春 《Agricultural Science & Technology》 CAS 2014年第3期412-416,421,共6页
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat... [Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited. 展开更多
关键词 Water immersion method Pot experiment method Vinyl chloride-vinyl acetate copolymer Nutrient release characteristics Soil mineral nitrogen
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Effect of Incorporation of Wheat Straw and Urea into Soil on Biomass Nitrogen and Nitrogen-Supplying Characteristics of Paddy Soil 被引量:23
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作者 SHENQI-RONG XUSHOU-MING 《Pedosphere》 SCIE CAS CSCD 1993年第3期201-205,共5页
Pot experiments were carried out to study the effect of incorporation of wheat straw and/ or urea into soil on biomass nitrogen and mineral nitrogen and its relation to the growth and yield of rice. The combined appli... Pot experiments were carried out to study the effect of incorporation of wheat straw and/ or urea into soil on biomass nitrogen and mineral nitrogen and its relation to the growth and yield of rice. The combined application of wheat straw and urea increased much more biomass nitrogen in soil than the application of wheat straw or urea alone and consequently increased the immobilization of urea nitrogen added and reduced the loss of urea nitrogen. An adequate nitrogen-supplying process to rice plant could be obtained if C / N ratio of the material added was about 20. The three yield components of rice were affected significantly by the status of nitrogen supplying. More than 30mg N / kg soil of mineral nitrogen at effective tillering stage, panicle initiation stage and filling stage should be maintained in order to get high rice yield, though the criteria varied with the different experimental conditions. 展开更多
关键词 biomass nitrogen mineral nitrogen UREA wheat straw
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Effects of adding water on seasonal variation of soil nitrogen availability under sandy grasslands in semi-arid region
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作者 黄晓星 于占源 +2 位作者 钱伟 徐大勇 艾桂艳 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期287-290,共4页
Water is usally thought of a limiting factor for the restoration of semi-arid ecosystem. In the growing season of 2006, a study was conducted to determine the effects of modeling precipitation on seasonal patterns in ... Water is usally thought of a limiting factor for the restoration of semi-arid ecosystem. In the growing season of 2006, a study was conducted to determine the effects of modeling precipitation on seasonal patterns in concentrations of soil-available nitrogen and to describe the seasonal patterns in soil nitrogen availability and seasonal variation in the rates of net nitrogen mineralization of topsoil at Daqinggou ecological station in Keerqin sand lands, Inner Mongolia Autonomous Region, China. Manipulation of water (80 mm) was designed to be added to experiment plots of sandy grasslands in dry season. Water addition (W) treatment and control (CK) treatment were separately taken in six replications and randomly assigned in 12 plots (4 m×4 m for each) with 2-m buffers betweens. Results showed that the content of soil inorganic nitrogen and net nitrogen mineralization rate were not affected by adding water in sandy grassland of Keerqin sand lands. Net ni- trogen mineralization rates ranged from 0.5μg·g^-1,month^-1 to 4 μg.g^-1.month^-1. The highest values of soil inorganic nitrogen and net nitrogen mineralization occurred on October 15 in control plots. The seasonal changes of soil inorganic nitrogen contents exhibited "V" shape pattern that was related to seasonal patterns of soil ammonium-N (ascending trend) and nitrate-N transformation (descending trend). 展开更多
关键词 nitrogen mineralization Inorganic nitrogen GRASSLAND Keerqin sand lands NITRIFICATION
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Conversion of Natural Ecosystems to Cropland Increases the Soil Net Nitrogen Mineralization and Nitrification in Tibet 被引量:12
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作者 YANG Li-Lin ZHANG Fu-Suo +3 位作者 MAO Ren-Zhao JU Xiao-Tang Cai Xiao-Bu LU Ya-Hai 《Pedosphere》 SCIE CAS CSCD 2008年第6期699-706,共8页
A comparative study was conducted to determine the NH4+ and NO3- concentrations in soil profiles and to examine the net nitrogen (N) mineralization and nitrification in adjacent forest, grassland, and cropland soils o... A comparative study was conducted to determine the NH4+ and NO3- concentrations in soil profiles and to examine the net nitrogen (N) mineralization and nitrification in adjacent forest, grassland, and cropland soils on the Tibetan Plateau. Cropland soil showed significantly higher inorganic N concentrations in soil profiles compared with forest and grassland soils. NO3- -N accounted for 70%–90% of inorganic N in cropland soil, while NH4+ -N was the main form of inorganic N in forest and grassland soils. The average net N mineralization rate at 0–20 cm depth was approximately twice in cropland soil (1.48 mg kg-1 d-1) as high as in forest (0.83 mg kg-1 d-1) or grassland soil (0.72 mg kg-1 d-1). Cropland showed strong net nitrification, with the net rate almost equal to the total net N mineralization. Urea addition stimulated soil respiration, particularly in forest soil. Most urea-N, however, remained as NH4+ in forest and grassland soils, while NO3- was the main form of inorganic N to increase in cropland soil. Higher rates of net nitrification in cropland soils suggest that land use change on the Tibetan Plateau may lead to high N losses through nitrate leaching. 展开更多
关键词 land use change microbial biomass NITRIFICATION nitrogen mineralization
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Effects of soil moisture and soil depth on nitrogen mineralization process under Mongolian pine plantations in Zhanggutai sandy land, P. R. China 被引量:18
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作者 CHENFu-sheng ZENGDe-hui +1 位作者 SINGHAnandNarain CHENGuang-sheng 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期101-104,共4页
The rates of soil N mineralization at soil depths of 0-15, 15-30, 30-45 and45-60 cm and moisture regimes were measured at three sand-fixation plantations of Pinus sylvestrisvar. mongolica by laboratory aerobic incubat... The rates of soil N mineralization at soil depths of 0-15, 15-30, 30-45 and45-60 cm and moisture regimes were measured at three sand-fixation plantations of Pinus sylvestrisvar. mongolica by laboratory aerobic incubation method. The results showed that average rates ofsoil net N-mineralization across soil depth varied from 1.06 to 7.52 mg · kg^(-1)·month^(-1) atsoil depths from 0 to 60 cm. Statistical analyses indicated that the effects of different soildepths, moistures and their interactions on net N-mineralization rates were significant (P < 0.05).The net N-mineralization rates significantly decreased with increasing soil depths and at depth 0-15cm accounted for 60.52% of that at depth of 0-60 cm. There was no difference in soil netN-mineralization rates between half and fully-saturated water treatments, however these rates weresubstantially higher than that without water treatment (P < 0.05). The factors influencing Nmineralization process have to be studied further in these semiarid pine ecosystems. 展开更多
关键词 laboratory aerobic incubation method nitrogen mineralization managementpractices sand-fixation forest semiarid region pinus sylvestris var· mongolica soil depth
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Modeling Nitrogen Mineralization in Paddy Soils of Shanghai Region 被引量:10
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作者 LI Hui-Lin, HAN Yong and CAI Zu-CongLaboratory of Material Cycling in Pedosphere, Institute of Soil Science, the Chinese Academy of Sciences, P. O. Box 821, Nanjing 210008 (China). E-mail: lihuilin@issas.ac.cn 《Pedosphere》 SCIE CAS CSCD 2003年第4期331-336,共6页
Six paddy soils of Shanghai, China, were studied after 120 days of anaerobicincubation at 25 deg C and 35 deg C. Four models, the effective accumulated temperature model, theone-component first-order exponential model... Six paddy soils of Shanghai, China, were studied after 120 days of anaerobicincubation at 25 deg C and 35 deg C. Four models, the effective accumulated temperature model, theone-component first-order exponential model (the one-pool model), the two-component first-orderexponential model (the two-pool model), and the two-component first-order plus zero-orderexponential model including a constant term (the special model), were fitted to the data of observedmineral-N during incubation using non-linear regression procedures. The two-pool model and thespecial model gave the best fits amongst the four models, and parameters in the special model weremore reasonable than those in the other three. Results showed that the special model gave a betterprediction of nitrogen mineralization under flooded conditions than the other three models. 展开更多
关键词 anaerobic incubation nitrogen mineralization paddy soil simulation model
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Nitrogen Mineralization in Soils Along a Vegetation Chronosequence in Hong Kong 被引量:5
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作者 L.M.MARAFA K.C.CHAU 《Pedosphere》 SCIE CAS CSCD 2005年第2期181-188,共8页
This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the rel... This research examined nitrogen mineralization in the top 10 cm of soils along a vegetation gradient in Hong Kong at sites where fire has been absent for 0, 1, 3, 6 and 17 years (at the time of the study), and the relationships between N mineralization and successional development of vegetation in the absence of fire. The sites including a newly burnt area (S1), short grassland (S2), tall grassland (S3), mixed tall grassland and shrubland (S4), and woodland (S5) were selected,and the in situ core incubation method was used to estimate nitrogen mineralization. Throughout the 60-day incubation in four periods, more nitrogen was mineralized at the S3 and S4 sites, the predominantly grassland sites, which contained the highest levels of soil organic matter (SOM) and total Kjeldahl nitrogen (TKN), than the S1 site, while immobilization occurred at the S2 and S5 sites. Leaching loss decreased with successional development of the vegetation, in the order of S1 > S2 > S3 > S4 > S5. The pattern of nitrogen uptake with ecological succession was less conspicuous, being complicated by the immediate effect of fire and possibly the ability of the woodland species to extract nitrogen from the deeper ground.In the absence of fire for 3 to 6 years, the build-up of SOM and TKN was accompanied by active mineralization, thus paving the way for the invasion of shrub and tree species. A close relationship existed between nitrogen mineralization and ecological succession with this vegetation gradient. Inherent mechanisms to preserve nitrogen in a fire-prone environment including immobilization and uptake and the practical relevance of nitrogen mineralization to reforestation are discussed. 展开更多
关键词 fire impact IMMOBILIZATION nitrogen mineralization successional development vegetation chronosequence
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Effect of forest thinning on soil net nitrogen mineralization and nitrification in a Cryptomeria japonica plantation in Taiwan 被引量:4
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作者 Shunyao Zhuang Jin Wang +1 位作者 Xiao Sun Mingkuang Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期571-578,共8页
We investigated the effect of forest thinning on soil nitrogen mineralization, nitrification and transformation in a Cryptomeria japoni-ca plantation at high elevation to provide basic data for forest manage-ment. We ... We investigated the effect of forest thinning on soil nitrogen mineralization, nitrification and transformation in a Cryptomeria japoni-ca plantation at high elevation to provide basic data for forest manage-ment. We chose four study plots for control, light, medium and heavy thinning treatment, and three sub-plots for buried bag studies at similar elevations in each treatment plot to measure the net N mineralization and nitrification rates in situ. The contents of soil inorganic N (ammonium and nitrate) were similar between treatments, but all varied with season, reaching maxima in September 2003 and 2004. The seasonal maximum net Nmin rates after four treatments were 0.182, 0.246, 0.303 and 0.560 mg?kg-1?d-1 in 2003, and 0.242,0.258,0.411 and 0.671 mg?kg-1?d-1in 2004, respectively. These estimates are approximate with the lower annual rates of N mineralization for this region. Forest thinning can enhance net N mineralization and microbial biomass carbon. The percentage of annual rates of Nmin for different levels of forest thinning compared with the control plot were 13.4%, 59.8%and 154.2%in 2003, and 0.1%, 58.8%and 157.7%in 2004 for light, medium, and heavy thinning, respectively. These differences were related to soil moisture, temperature, precipita-tion, and soil and vegetation types. Well-planned multi-site comparisons, both located within Taiwan and the East-Asia region, could greatly im-prove our knowledge of regional patterns in nitrogen cycling. 展开更多
关键词 Cryptomeria japonica plantation forest thinning NITRIFICATION seasonal variation soil nitrogen mineralization
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Nitrogen Mineralization Potentials of Upland Soils inCentral China 被引量:4
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作者 CHENJIA-ZHOU QINHUA-CHANG 《Pedosphere》 SCIE CAS CSCD 1995年第2期127-133,共7页
Nitrogen mineralization potentials of 15 soil samples were studied by the methods of soil asrobic incuba-tion, and the correlation between the potentials and the amounts of nitrogen taken up by rye grass (Lolium.multi... Nitrogen mineralization potentials of 15 soil samples were studied by the methods of soil asrobic incuba-tion, and the correlation between the potentials and the amounts of nitrogen taken up by rye grass (Lolium.multifiorum Lam.) in pot culture was calculated. The soils were collected from Hubei Province in Cen-tral China. Soil nitrogen mineralization potentials (N_O) were calculated and optimized by a quick-BASICprogram. N_O ranged from 60 mg kg ̄(-1) to 340 mg kg ̄(-1), which accounted for 9.1% to 34.6% of the totalnitrogen content. Among the examined soils, yellow-brown soil collected from Wuhan had the largest N_Oand brown-red soil from Xianning had the smallest one. The mineralization rate constants (k) ranged from0.00556 d ̄(-1) to 0.01280 d ̄(-1) , in average 0.00882 d ̄(-1) . Chao soil from Wuhan had the greatest k while yellow-cinnamon soil from Zhaoyang had the smallest one. There were apparent differences between mineralizationparameters (N_O and k) optimized and non-optimized ones. Optimized N_O had a better correlation thannon-optimized N_O with the amount of nitrogen accumulated in the aerial parts of rye grass. N_O , N_O × k andN_t(accumulated mineralized nitrogen within time t) could be used as indexes of soil nitrogen supply. Amongthem N_t was the best, which was significantly correlated with the amounts of nitrogen accumulated in theaerial parts of rye grass harvested at three different times. 展开更多
关键词 aerobic incubation nitrogen mineralization potential parameter optimization upland soil
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Effect of Fluctuating Temperatures on Forest SoilNitrogen Mineralization 被引量:3
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作者 LIAOLIPING P.INESON 《Pedosphere》 SCIE CAS CSCD 1997年第1期31-34,共4页
Nitrogen mineralization in forest soil was studied in laboratory by incubating undisturbed soil cores enclosed within PVC columns at different temperatures to compare the effect of fluctuating temperature with that of... Nitrogen mineralization in forest soil was studied in laboratory by incubating undisturbed soil cores enclosed within PVC columns at different temperatures to compare the effect of fluctuating temperature with that of constant temperature, and to find out whether soil nitrification shows linearity over time. The results showed that there was no significant difference between soil nitrification at fluctuating temperature and that at constant temperature, and suggested that it must be careful to make the conclusion that soil nitrification has linearity over time. 展开更多
关键词 fluctuating temperature LINEARITY nitrogen mineralization
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Integrated application of February Orchid(Orychophragmus violaceus) as green manure with chemical fertilizer for improving grain yield and reducing nitrogen losses in spring maize system in northern China 被引量:8
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作者 BAI Jin-shun CAO Wei-dong +3 位作者 XIONG Jing ZENG Nao-hua GAO Song-juan Shimizu Katsuyoshi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2490-2499,共10页
The development of more efficient management systems is crucial to achieving high grain yields with high nitrogen use efficiency(NUE). February Orchid-spring maize rotation system is a newly established planting sys... The development of more efficient management systems is crucial to achieving high grain yields with high nitrogen use efficiency(NUE). February Orchid-spring maize rotation system is a newly established planting system with the benefits of ground cover and potential wind erosion in northern China. A field experiment was conducted to evaluate the effects of integrated application of February Orchid as green manure with reduction of chemical fertilizers(INTEGRATED) on spring maize yield, N uptake, ammonium volatilization, and soil residual mineral N in northern China. Compared to farmers' traditional fertilization(CON), integrated application of February Orchid as green manure with 30% reduction of nitrogen fertilizers(INTEGRATED) increased maize grain yield and biomass by 9.9 and 10.2%, respectively. The 0–100 cm soil residual Nmin at harvest was decreased by 58.5% and thus nitrogen use efficiency was increased significantly by 26.7%. The nitrogen balance calculation further demonstrated that the INTEGRATED approach performed better than CON with lower apparent nitrogen loss(decreased by 48.9%) which evidenced by the ammonium volatilization of top-dressing fertilizer was decreased by 31.1%, the N_(min) movement to the deeper soil layers was reduced, and the apparent nitrogen leaching loss nearly equal to 0 under the INTEGRATED treatment. Therefore, in northern China, integrated application of green manure and chemical fertilizers is an efficient management approach for improving maize yields and NUE simultaneously. 展开更多
关键词 cover crop ammonium volatilization mineral nitrogen nitrogen use efficiency nitrogen balance
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Temperature dependence of nitrogen mineralization and microbial status in O_H horizon of a temperate forest ecosystem 被引量:2
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作者 Ali Bagherzadeh Rainer Brumme Friedrich Beese 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期37-43,共7页
It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nit... It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nitrogen in humus, and consequently development in OH horizon (humus horizon). To quantify the effect of temperature on biochemical processes controlling the rate of OH layer development three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany by an incubation experiment of OH layer for three months. Comparing the fitted curves for temperature sensitivity of OH layers in relation to net N mineralization revealed positive correlation across all sites. For the whole data set of all stands, a Q10 (temperature sensitivity index) value of 2.35-2.44 dependent on the measured units was found to be adequate for describing the temperature dependency of net N mineralization at experimental site. Species-specific differences of substrate quality did not result in changes in biochemical properties of OH horizon of the forest floors. Temperature elevation increased net N mineralization without significant changes in microbial status in the range of I to 15℃. A low Cmic /Corg (microbial carbon/organic carbon) ratio at 20℃ indicated that the resource availability for decomposers has been restricted as reflected in significant decrease of microbial biomass. 展开更多
关键词 BEECH SPRUCE nitrogen mineralization forest floor TEMPERATURE temperature sensitivity index (Q10)
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Response of nitrogen mineralization dynamics and biochemical properties to litter amendments to soils of a poplar plantation 被引量:2
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作者 Xiaomin Ge Shiping Deng +4 位作者 Ling Zhu Yong Li Zhiyuan Jia Ye Tian Luozhong Tang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期913-922,共10页
Understanding the impact of plant litters on soil nitrogen (N) dynamics could facilitate development of management strategies that promote plantation ecosystem function. Our objective was to evaluate the effects of ... Understanding the impact of plant litters on soil nitrogen (N) dynamics could facilitate development of management strategies that promote plantation ecosystem function. Our objective was to evaluate the effects of different litter types on N mineralization and availability, microbial biomass, and activities of L-asparaginase and odiphenol oxidase (o-DPO) in soils of a poplar (Populus deltoides) plantation through 24 weeks of incubation experiments. The tested litters included foliage (F), branch (B), or root (R) of poplar trees, and understory vegetation (U) or a mixture of F, B, and U (M). Litter amendments led to rapid N immobilization during the first 4 weeks of incubation, while net N mineralization was detected in all tested soils from 6 to 24 weeks of incubation, with zero-order reaction rate constants (k) ranging from 7.7 to 9.6 mg N released kg-1 soil wk-1. Moreover, litter addition led to increased (C) 49-128% and increased microbial biomass carbon MBC:MBN ratio by 5-92%, strengthened activities of L-aspaxaginase and o-DPO by 14-74%; Up to about 37 kg N ha-1 net increase in mineralized N in litter added soils during 24 weeks of incubation suggests that adequate poplar and understory litter management could lead to reduced inputs while facilitate sustainable and economic viable plantation production. 展开更多
关键词 Plant litter nitrogen mineralization Soilmicrobial biomass L-ASPARAGINASE o-diphenol oxidase
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Soil-nitrogen net mineralization increased after nearly six years of continuous nitrogen additions in a subtropical bamboo ecosystem 被引量:2
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作者 Yin-long Xiao Li-hua Tu +4 位作者 Gang Chen Yong Peng Hong-ling Hu Ting-xing Hu Li Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期949-956,共8页
In order to understand the effects of increasing atmospheric nitrogen (N) deposition on the subtropical bamboo ecosystem, a nearly six-year field experiment was conducted in a Pleioblastus amarus plantation in the r... In order to understand the effects of increasing atmospheric nitrogen (N) deposition on the subtropical bamboo ecosystem, a nearly six-year field experiment was conducted in a Pleioblastus amarus plantation in the rainy region of SW China, near the western edge of Sichuan Basin. Four N treatment levels---control (no N added), low- N (50 kg N ha-1 a-l), medium-N (150 kg N ha-1 a-l), and high-N (300 kg N ha-1 a-1)--were applied monthly in the P. amarus plantation starting in November 2007. In June 2012, we collected intact soil cores in the bamboo plantation and conducted a 30-day laboratory incubation experiment. The results showed that the soil N net miner- alization rate was 0.96 4- 0.10 mg N kg-1 day-1, under control treatment. N additions stimulated the soil N net mineralization, and the high-N treatment significantly increased the soil N net mineralization rate compared with the control. Moreover, the soil N net mineralization rate was significantly and positively correlated with the fine root biomass, the soil microbial biomass nitrogen content and the soil initial inorganic N content, respectively,whereas it was negatively correlated with the soil pH value. There were no significant relationships between the soil N net mineralization rate and the soil total nitrogen (TN) content and the soil total organic carbon content and the soil C/N ratio and the soil microbial biomass carbon con- tent, respectively. These results suggest that N additions would improve the mineral N availability in the topsoil of the P. amarus plantation through the effects of N additions on soil chemical and physical characteristics and fine-root biomass. 展开更多
关键词 nitrogen addition Soil nitrogen net mineralization Soil chemical and physical characteristics Fine root biomass Pleioblastus amarus plantation
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Black locust coppice stands homogenize soil diazotrophic communities by reducing soil net nitrogen mineralization 被引量:1
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作者 Kun Li Huimei Tian +5 位作者 W.Keith Moser Steven T.Overby L.Scott Baggett Ruiqiang Ni Chuanrong Li Weixing Shen 《Forest Ecosystems》 SCIE CSCD 2022年第3期289-300,共12页
Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivit... Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivity of BL declines.Whether soil microbial communities are affected and how these groups correlate with the nitrogen mineralization process across multi-generation stands remains unclear.Methods:We investigated the composition and structure of free-living nitrogen-fixing microorganisms(diazotrophs)by sequencing the marker gene nifH and compared these results to levels of soil nitrogen mineralization in the bulk soil and rhizosphere in black locust plantations on Mount Tai,China.Results:The results showed multi-generation BL coppice plantations decreased the total soil nitrogen(N),soil phosphorus(P),soil microbial biomass N(MBN),soil microbial biomass C(MBC),soil nitrification rate(Rn),soil ammonification rate(Ra),and net soil N mineralization rate(Rm),but significantly increased the concentration of soil NH_(4þ)-N to maintain sufficient NO_(3)^(-)N.The dominant species in bulk soil and rhizosphere changed from Rhodopseudomonas(22.62%and 15.76%),unclassified_c_Alphaproteobacteria(22.37%and 29.28%),unclassified_o_Rhizobiales(15.40%and 13.31%),Bradyrhizobium(12.00%and 11.74%)in seedling plantations to Bradyrhizobium(45.95%and 47.86%)and Rhodopseudomonas(43.56%and 41.84%)in coppice plantations,respectively.Mantel test and Redundancy analysis(RDA)revealed that Rn,Ra,and Rm were the most important factors shaping the diazotrophic communities.Conclusions:Our results suggest that the multi-generation BL coppice plantation can homogenize soil diazotrophic communities,which is mainly regulated by the available N loss caused by nitrogen mineralization.Strengthening the management technology of coppice plantations will provide more beneficial external consumption. 展开更多
关键词 Black locust plantation nifH gene nitrogen mineralization COPPICE Soil nutrient
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