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含钙添加剂处理下不同秸秆腐解产物可溶性有机质三维荧光特征变化 被引量:2
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作者 夏明明 刘佳 +6 位作者 吴萌 樊剑波 刘晓利 陈玲 马昕伶 李忠佩 刘明 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第1期118-124,共7页
秸秆是优质的有机资源,研究含钙添加剂种类及添加量对不同秸秆腐解产物可溶性有机物(DOM)组成性质差异,可为秸秆高效腐熟利用提供理论依据和技术参考。以花生秸秆和水稻秸秆为供试物料,通过添加不同含钙添加剂草酸钙(CaC_(2)O_(4))和氢... 秸秆是优质的有机资源,研究含钙添加剂种类及添加量对不同秸秆腐解产物可溶性有机物(DOM)组成性质差异,可为秸秆高效腐熟利用提供理论依据和技术参考。以花生秸秆和水稻秸秆为供试物料,通过添加不同含钙添加剂草酸钙(CaC_(2)O_(4))和氢氧化钙[Ca(OH)_(2)]及不同添加量(4%、 8%),进行秸秆腐解试验。测定腐解产物养分含量,并利用三维荧光光谱(3DEEM)技术和平行因子方法(PARAFAC)探究秸秆腐解产物DOM的化学组成变化特征。结果表明:(1)总体上,草酸钙处理的秸秆腐解物总碳含量显著大于氢氧化钙处理;高量添加剂处理的秸秆腐解产物总碳含量小于低量处理;花生秸秆腐解产物的总氮、总磷和总钾高于水稻秸秆腐解产物。(2)通过3DEEM-PARAFAC方法分析腐解产物DOM组成,共识别出类胡敏酸(C1)、类胡敏酸(C2)和类色氨酸(C3)三种荧光组分;不同添加剂类型、添加量和不同秸秆类型对腐解产物DOM荧光组分的影响较为复杂,没有明显规律,但是总体上氢氧化钙处理的秸秆腐解产物DOM的C1和C2组分比例大于草酸钙处理,而草酸钙处理的秸秆腐解产物DOM的C3组分比例显著高于氢氧化钙处理;秸秆腐解产物DOM中组分C1、 C2与组分C3呈显著负相关;组分C2含量与总碳含量呈显著负相关。(3)氢氧化钙处理的秸秆腐解产物DOM的腐殖化指数(HIX)明显高于草酸钙处理,而草酸钙处理的秸秆腐解产物DOM生物源指数(BIX)明显高于氢氧化钙处理;高量草酸钙处理秸秆腐解产物DOM主要来自于微生物的转化,而其他处理DOM来自于微生物转化和陆生植物;不同添加量处理下秸秆腐解产物DOM的荧光指数没有明显变化规律;花生秸秆腐解产物DOM的HIX、 BIX和荧光指数(McKnight index)均高于水稻秸秆;秸秆腐解产物DOM中McKnight和HIX呈显著负相关,和BIX间呈极显著正相关,而秸秆腐解产物DOM中BIX和总碳含量呈显著正相关。上述结果表明,氢氧化钙可以促进秸秆腐解以及腐解产物的腐殖化,其中高量氢氧化钙处理的花生秸秆效果较好。 展开更多
关键词 含钙添加剂 秸秆 可溶性有机物 三维荧光 平行因子分析
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Changes in Soil C and N Contents and Mineralization Across a Cultivation Chronosequence of Paddy Fields in Subtropical China 被引量:17
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作者 li zhong-pei ZHANG Tao-lin +1 位作者 HAN Feng-Xiang P. FEliX-HENNINGSEN 《Pedosphere》 SCIE CAS CSCD 2005年第5期554-562,共9页
Dynamics of soil organic matter in a cultivation chronosequence of paddy fields were studied in subtropical China.Mineralization of soil organic matter was determined by measuring CO2 evolution from soil during 20 day... Dynamics of soil organic matter in a cultivation chronosequence of paddy fields were studied in subtropical China.Mineralization of soil organic matter was determined by measuring CO2 evolution from soil during 20 days of laboratoryincubation. In the first 30 years of cultivation, soil organic C and N contents increased rapidly. After 30 years, 0-10 cmsoil contained 19.6 g kg-1 organic C and 1.62 g kg-1 total N, with the corresponding values of 18.1 g kg-1 and 1.50g kg-1 for 10-20 cm, and then remained stable even after 80 years of rice cultivation. During 20 days incubation themineralization rates of organic C and N in surface soil (0-10 cm) ranged from 2.2% to 3.3% and from 2.8% to 6.7%,respectively, of organic C and total N contents. Biologically active C size generally increased with increasing soil organicC and N contents. Soil dissolved organic C decreased after cultivation of wasteland to 10 years paddy field and thenincreased. Soil microbial biomass C increased with number of years under cultivation, while soil microbial biomass Nincreased during the first 30 years of cultivation and then stabilized. After 30 years of cultivation surface soil (0-10 cm)contained 332.8 mg kg-1 of microbial biomass C and 23.85 mg kg-1 of microbial biomass N, which were 111% and 47%higher than those in soil cultivated for 3 years. It was suggested that surface soil with 30 years of rice cultivation insubtropical China would have attained a steady state of organic C content, being about 19 g kg-1. 展开更多
关键词 cultivation chronosequence MINERALIZATION paddy fields soil C soil N
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Differences in Organic C Mineralization Between Aerobic and Submerged Conditions in Paddy Soils of Southern Jiangsu Province,China 被引量:13
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作者 HAO Rui-jun li zhong-pei CHE Yu-ping 《Agricultural Sciences in China》 CAS CSCD 2011年第9期1410-1418,共9页
Moisture regime plays a crucial role in the mineralization of soil organic carbon (SOC). In this paper, the dynamics of SOC mineralization in typical paddy soils of Changshu, Jiangsu Province, China, was investigate... Moisture regime plays a crucial role in the mineralization of soil organic carbon (SOC). In this paper, the dynamics of SOC mineralization in typical paddy soils of Changshu, Jiangsu Province, China, was investigated by incubation test in laboratory. The differences in SOC mineralization under aerobic and submerged conditions of paddy soils were also studied. Results showed that the daily mineralization of SOC under different moisture regimes was significantly different in the whole incubation period, at the beginning of the incubation, it decreased quickly under aerobic condition, but increased rapidly under submerged condition, and both remained constant after 10 d of incubation. The differences in SOC mineralization were found to be mainly at the beginning period of the incubation and decreased along with the incubation time. Thus, the difference was not significantly different at the later incubation period. The respiration intensity, daily and cumulative mineralization of SOC under aerobic condition was 2.26-19.11, 0.96-2.41, and 0.96-2.41 times than those .under submerged condition, respectively. Statistic analyses showed that the higher the contents of microbial biomass carbon and nitrogen, the more significant difference in respiration intensity between aerobic and submerged conditions, but the higher the contents of microbial biomass nitrogen and dissolved organic carbon, the more significant difference in daily mineralization of SOC between the two conditions. The decrease in soil microbial activity under submerged condition was the main reason leading to the decrease in respiration intensity, but the decrease in SOC mineralization was also correlated with the changes in dissolved organic carbon over the whole incubation period. 展开更多
关键词 moisture regime paddy soil SOC mineralization aerobic condition submerged condition difference
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Discrepancy in Response of Rice Yield and Soil Fertility to Long-Term Chemical Fertilization and Organic Amendments in Paddy Soils Cultivated from Infertile Upland in Subtropical China 被引量:12
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作者 liU Ming li zhong-pei +2 位作者 ZHANG Tao-lin JIANG Chun-yu CHE Yu-ping 《Agricultural Sciences in China》 CAS CSCD 2011年第2期259-266,共8页
From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon(SOC),and total N to long-term NPK fertilizat... From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon(SOC),and total N to long-term NPK fertilization or NPK combined with organic amendments.The field trials included NPK(N,P,K fertilizer),NPKRS(NPK combined with rice straw),NPK2RS(NPK combined with double amount of rice straw),NPKPM(NPK combined with pig manure) and NPKGM(NPK combined with green manure) and the cropping system was rice-rice(Oryza sativa L.) rotation.Annual rice yield,straw biomass,and harvesting index increased steadily with cultivation time in all treatments.Average annual rice yield from 1991 to 2006 was ranged from 7 795 to 8 572 kg ha-1 among treatments.Rice yields in treatments with organic amendments were usually higher than that in treatment with NPK.Contents of SOC and total N also increased gradually in the cultivation years and reached the level of 7.82 to 9.45 and 0.85 to 1.03 g kg-1,respectively,in 2006.Soil fertilities in treatments with chemical fertilization combined with organic amendments were relatively appropriate than those in treatment with NPK.There was obvious discrepancy between cumulative characters of rice yield and soil organic fertility in newly formed paddy field.Compared with relatively high rate of crop productivity improvement,cumulative rates of SOC and total N were much lower in our study.SOC and total N contents were still less than half of those in local highly productive paddy soils after 17 years cultivation in subtropical China.Present work helps to better understand the development of infertile paddy soils and to estimate the potential of yield improvement in this region. 展开更多
关键词 paddy field rice yield SOC total N long-term field experiment
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Bacterial diversity and community composition changes in paddy soils that have different parent materials and fertility levels 被引量:3
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作者 MA Xin-ling liU Jia +5 位作者 CHEN Xiao-fen li Wei-tao JIANG Chun-yu WU Meng liU Ming li zhong-pei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第10期2797-2806,共10页
Parent materials and the fertility levels of paddy soils are highly variable in subtropical China.Bacterial diversity and community composition play pivotal roles in soil ecosystem processes and functions.However,the ... Parent materials and the fertility levels of paddy soils are highly variable in subtropical China.Bacterial diversity and community composition play pivotal roles in soil ecosystem processes and functions.However,the effects of parent material and fertility on bacterial diversity and community composition in paddy soils are unclear.The key soil factors driving the changes in bacterial diversity,community composition,and the specific bacterial species in soils that are derived from different parent materials and have differing fertility levels are unknown.Soil samples were collected from paddy fields in two areas with different parent materials(quaternary red clay or tertiary sandstone)and two levels of fertility(high or low).The variations in bacterial diversity indices and communities were evaluated by 454 pyrosequencing which targeted the V4–V5 region of the 16S rRNA gene.The effects of parent material and fertility on bacterial diversity and community composition were clarified by a two-way ANOVA and a two-way PERMANOVA.A principal coordinate analysis(PCoA),a redundancy analysis(RDA),and multivariate regression trees(MRT)were used to assess changes in the studied variables and identify the factors affecting bacterial community composition.Co-occurrence network analysis was performed to find correlations between bacterial genera and specific soil properties,and a statistical analysis of metagenomic profiles(STAMP)was used to determine bacterial genus abundance differences between the soil samples.The contributions made by parent material and soil fertility to changes in the bacterial diversity indices were comparable,but soil fertility accounted for a larger part of the shift in bacterial community composition than the parent material.Soil properties,especially soil texture,were strongly associated with bacterial diversity.The RDA showed that soil organic carbon(SOC)was the primary factor influencing bacterial community composition.A key threshold for SOC(25.5 g kg^(–1))separated low fertility soils from high fertility soils.The network analysis implied that bacterial interactions tended towards cooperation and that copiotrophic bacteria became dominant when the soil environment improved.The STAMP revealed that copiotrophic bacteria,such as Massilia and Rhodanobacter,were more abundant in the high fertility soils,while oligotrophic bacteria,such as Anaerolinea,were dominant in low fertility soils.The results showed that soil texture played a role in bacterial diversity,but nutrients,especially SOC,shaped bacterial community composition in paddy soils with different parent materials and fertility levels. 展开更多
关键词 MICROORGANISMS soil biodiversity soil fertility soil texture soil nutrients
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Optimize nitrogen fertilization location in root-growing zone to increase grain yield and nitrogen use efficiency of transplanted rice in subtropical China 被引量:9
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作者 WU Meng liU Ming +3 位作者 liU Jia li Wei-tao JIANG Chun-yu li zhong-pei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期2073-2081,共9页
The optimized nitrogen fertilization location differs in different rice-growing regions. We optimized nitrogen deep-point application in root-growing zone(NARZ) for transplanted rice in subtropical China. Field plot... The optimized nitrogen fertilization location differs in different rice-growing regions. We optimized nitrogen deep-point application in root-growing zone(NARZ) for transplanted rice in subtropical China. Field plot experiments were conducted over two years(2014–2015) in a double-rice cropping system to evaluate the effects of nitrogen(N) fertilizer location on grain yield and N use efficiency(NUE). Four different nitrogen deep-point application methods(DN) were compared with traditional broadcast application(BN) using granular urea. The results showed that grain yield, recovery efficiency of N(REN), agronomic efficiency of N(AEN), and partial factor productivity of N(PFP_N) significantly increased 10.3–63.4, 13.7–56.7, 24.7–201.9 and 10.2–63.4%, respectively, in DN treatment compared to BN, respectively. We also find that DN treatments increased grain yield as well as grain N content, and thus grain quality, in comparison with conventional BN treatment. Correlation analysis indicated that significant improvement in grain yield and NUE mainly resulted from increases in productive panicle number and grain N content. In our proposed NARZ method, granular urea should be placed 0 to 5 cm around the rice seeding at a 12-cm depth druing rice transplanting. In NARZ, balanced application of N, P and K further improved grain yield and NUE over treatments with a single N deep-point application. High N uptake by the rice plant did not cause significant soil fertility depletion, demonstrating that this method could guarantee sustainable rice production. 展开更多
关键词 N recovery efficiency grain yield deep-point application N application in root-growing zone
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钙盐对秸秆腐解过程及产物可溶性有机质三维荧光光谱特征的影响 被引量:2
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作者 仇存璞 唐晓雪 +8 位作者 文喜贤 马昕伶 夏明明 李忠佩 吴萌 李桂龙 刘凯 刘凯丽 刘明 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第7期2301-2307,共7页
秸秆是重要的有机资源,研究不同钙盐对秸秆腐解过程的影响及腐解产物性质差异,为有机物料高效利用、高质腐熟提供理论依据和技术参考。以水稻秸秆为供试物料,通过添加不同类型钙盐(不添加(CK),添加CaC_(2)O_(4),Ca(OH)_(2),CaCO_(3),CaC... 秸秆是重要的有机资源,研究不同钙盐对秸秆腐解过程的影响及腐解产物性质差异,为有机物料高效利用、高质腐熟提供理论依据和技术参考。以水稻秸秆为供试物料,通过添加不同类型钙盐(不添加(CK),添加CaC_(2)O_(4),Ca(OH)_(2),CaCO_(3),CaCl_(2),CaSO_(4)和Ca(H_(2)PO_(4))_(2)),进行室内秸秆腐解试验,测定不同腐解时期(30,60和180 d)各处理秸秆的腐解速率及腐解产物化学性质变化,利用三维荧光光谱(3DEEM)技术和平行因子方法(PARAFAC)探究秸秆腐解产物可溶性有机质(DOM)的化学组成变化特征。结果表明:(1)较对照而言,CaC_(2)O_(4),Ca(OH)_(2),CaCO_(3)和CaSO_(4)处理秸秆碳的转化率中分别增加了25.6%,44.1%,33.6%和29.7%,在CaCl_(2)和Ca(H_(2)PO_(4))_(2)处理分别减小了76.8%和17.5%;CaC_(2)O_(4)和Ca(OH)_(2)处理显著增加腐解产物pH;CaCl_(2)和Ca(H_(2)PO_(4))_(2)处理显著增加腐解产物的电导率(EC);在各腐解时期,CaC_(2)O_(4)和Ca(OH)_(2)处理腐殖质相对含量分别高于对照3.4%~20.9%和2.3%~25.3%。(2)通过3DEEM-PARAFAC方法分析腐解产物DOM组成,共识别出类色氨酸(C1)、类富里酸(C2)和类胡敏酸(C3)三种荧光组分;Ca(OH)_(2),CaCO_(3)和CaC_(2)O_(4)处理类胡敏酸/类富里酸比值(H/F)高于CK处理,增加了腐解产物的复杂程度;Ca(OH)_(2),CaCO_(3)和CaC_(2)O_(4)处理腐解产物DOM的腐殖化(HIX)指数略高于CK处理,Ca(H_(2)PO_(4))_(2),CaSO_(4)和CaCl_(2)处理的HIX指数显著低于CK处理。(3)相关性分析表明,pH和EC是添加钙盐后影响秸秆腐解的主控因子,秸秆腐解产物腐殖化程度与pH正相关,与EC负相关。综上所述,CaC_(2)O_(4),Ca(OH)_(2)和CaCO_(3)处理可以促进秸秆的腐殖化进程,提高腐解产物品质,Ca(H_(2)PO_(4))_(2)和CaCl_(2)起相反作用,另外pH和EC为影响秸秆腐殖化的主控因子。该研究可为选择合适的钙盐添加剂从而促进秸秆腐解、提高秸秆腐解产物品质提供科学参考。 展开更多
关键词 钙盐 秸秆腐解产物 可溶性有机质 三维荧光光谱 平行因子分析
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竹豆间种对柑橘园土壤化学性质及微生物碳源代谢特征的影响 被引量:4
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作者 马昕伶 秦文婧 +9 位作者 刘凯 刘佳 樊剑波 李忠佩 陈晓芬 吴萌 江春玉 刘凯丽 武志峰 刘明 《中国土壤与肥料》 CAS CSCD 北大核心 2021年第5期200-206,共7页
选择红壤丘陵区典型柑橘园,设置清耕、自然生草和竹豆间种3种种植模式,研究不同种植模式下柑橘园土壤化学性质、微生物生物量、微生物碳源代谢特征变化,并探明主导碳源代谢特征变化的土壤环境因素。结果表明,相对于清耕和自然生草种植模... 选择红壤丘陵区典型柑橘园,设置清耕、自然生草和竹豆间种3种种植模式,研究不同种植模式下柑橘园土壤化学性质、微生物生物量、微生物碳源代谢特征变化,并探明主导碳源代谢特征变化的土壤环境因素。结果表明,相对于清耕和自然生草种植模式,竹豆间种模式下柑橘园土壤pH提高了24.03%和21.65%,有机碳、碱解氮、有效磷、速效钾分别提高了19.40%和25.14%、14.02%和18.61%、2.69和3.12倍、63.40%和1.14倍。柑橘园土壤微生物生物量碳受种植模式影响不显著,但是竹豆间种显著提高了土壤微生物碳源利用能力(Average well color development,AWCD)和均匀度指数。竹豆间种模式下土壤微生物对于酰胺、氨基酸、酚类和多聚物等多个大类碳源的代谢强度显著高于其他处理,清耕模式下土壤微生物对于糖类尤其是赤藓糖醇、葡萄糖-1-磷酸、D-纤维二糖的代谢强度显著高于其他处理。逐步回归分析结果表明,微生物的碳源利用能力和土壤有机碳密切相关,而pH是影响微生物功能多样性及多个特异性碳源代谢强度的首要因素。冗余分析结果表明,柑橘园土壤微生物碳源利用模式受土壤环境因素影响的大小顺序为:pH>有效磷>碱解氮>有机碳>速效钾。因此,竹豆间种能够缓解柑橘园土壤酸化,提高土壤养分含量,改善微生物群落结构和功能多样性,有利于柑橘园土壤生态健康和可持续利用。 展开更多
关键词 竹豆间种 柑橘园 红壤丘陵区 微生物生物量碳 微生物碳源代谢特征
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红壤旱地上4种冬绿肥适宜播种量研究 被引量:3
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作者 陈晓芬 张路平 +6 位作者 秦文婧 陈静蕊 徐样庚 刘明 李忠佩 徐昌旭 刘佳 《草业学报》 CSCD 北大核心 2021年第10期137-146,共10页
以红壤旱地4种冬绿肥(鼠茅草、毛叶苕子、冬油菜和肥田萝卜)为研究对象,通过田间试验研究不同播种量对供试绿肥品种生物量、养分含量和养分积累量的影响,以期确定4种冬绿肥在红壤旱地的适宜播种量,为绿肥种植提高土壤肥力、保障红壤区... 以红壤旱地4种冬绿肥(鼠茅草、毛叶苕子、冬油菜和肥田萝卜)为研究对象,通过田间试验研究不同播种量对供试绿肥品种生物量、养分含量和养分积累量的影响,以期确定4种冬绿肥在红壤旱地的适宜播种量,为绿肥种植提高土壤肥力、保障红壤区农业可持续发展提供理论依据。试验设5个播种量处理,分别为15、30、45、60和75 kg·hm^(-2)。结果表明,随播种量增加,4种冬绿肥地上部生物量(鲜重和干重)呈先上升后下降或趋于平稳的变化趋势。所有播种量处理中,鼠茅草在30 kg·hm^(-2)播种量下生物量最大,而其余3种绿肥生物量达最大时的播种量为60 kg·hm^(-2)。播种量显著影响绿肥植株体内碳、氮、磷、钾、钙和镁元素的含量,不同绿肥品种的同一养分元素含量对播种量的响应也有明显差异。4种绿肥养分元素的积累量均随播种量增加呈先上升后下降的变化趋势。综合考虑绿肥的生物量和养分积累量,通过回归方程拟合发现,本试验条件下鼠茅草、毛叶苕子、冬油菜和肥田萝卜在红壤旱地上的适宜播种量范围分别为30.7~32.7 kg·hm^(-2)、50.4~63.4 kg·hm^(-2)、53.5~61.4 kg·hm^(-2)和63.0~80.1 kg·hm^(-2)。 展开更多
关键词 冬绿肥 播种量 生物量 养分含量 养分积累量
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Environmental Problems From Tea Cultivation in Japan and a Control Measure Using Calcium Cyanamide 被引量:28
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作者 K. OH T. KATO +1 位作者 li zhong-pei li Fa-Yun 《Pedosphere》 SCIE CAS CSCD 2006年第6期770-777,共8页
A field experiment, involving lime N (calcium cyanamide, CaCN2) fertilization as a control measure, was conducted to study environmental problems induced by long-term heavy N application in Japanese tea fields. Long-t... A field experiment, involving lime N (calcium cyanamide, CaCN2) fertilization as a control measure, was conducted to study environmental problems induced by long-term heavy N application in Japanese tea fields. Long-term tea cultivation caused serious soil acidification. Seventy-seven percent of the 70 tea fields investigated had soil pH values below 4.0, and 9% below 3.0, with the lowest value of 2.7. Moreover, excess N application in tea fields put a threat to plant growth, induced serious nitrate contamination to local water, and caused high nitrous oxide loss. Compared with the conventional high N application treatment (1100 kg N ha-1) without lime N, the low N application (400 kg N ha-1) with calcium cyanamide effectively stopped soil acidification as well as achieved the same or slightly higher levels in tea yield and in total N and amino acid contents of tea shoots. The application of calcium cyanamide could be a suitable fertilization for the prevention of environmental problems in tea cultivation. 展开更多
关键词 calcium cyanamide nitrous oxide emissions soil acidification tea cultivation water contamination
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Soil N transformation and microbial community structure as affected by adding biochar to a paddy soil of subtropical China 被引量:11
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作者 li Ming liU Ming +2 位作者 li zhong-pei JIANG Chun-yu WU Meng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期209-219,共11页
We have had little understanding on the effects of different types and quantities of biochar amendment on soil N transformation process and the microbial properties. In this study, various biochars were produced from ... We have had little understanding on the effects of different types and quantities of biochar amendment on soil N transformation process and the microbial properties. In this study, various biochars were produced from straw residues and wood chips, and then added separately to a paddy soil at rates of 0.5, 1 and 2% (w/w). The effects of biochar application on soil net N mineralization and nitrification processes, chemical and microbial properties were examined in the laboratory experiment. After 135 d of incubation, addition of straw biochars increased soil pH to larger extent than wood biochars. The biochar-amended soils had 37.7, 7.3 and 227.6% more soil organic carbon (SOC), available P and K contents, respectively, than the control soil. The rates of net N mineralization and nitrification increased significantly as biochars quantity rose, and straw biochars had greater effect on N transformation rate than wood biochars. Soil microbial biomass carbon increased by 14.8, 45.5 and 62.5% relative to the control when 0.5, 1 and 2% biochars (both straw- and wood-derived biochars), respectively, were added. Moreover, biochars amendments significantly enhanced the concentrations of phospholipid fatty acids (PLFAs), as the general bacteria abundance increased by 161.0% on average. Multivariate analysis suggested that the three rice straw biochar (RB) application levels induced different changes in soil microbial community structure, but there was no significant difference between RB and masson pine biochar (MB) until the application rate reached 2%. Our results showed that biochars amendment can increase soil nutrient content, affect the N transformation process, and alter soil microbial properties, all of which are biochar type and quantity dependent. Therefore, addition of biochars to soil may be an appropriate way to disposal waste and improve soil quality, while the biochar type and addition rate should be taken into consideration before its large-scale application in agro-ecosystem. 展开更多
关键词 straw biochar wood biochar N transformation phospholipid fatty acids multivariate analysis
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Changes in Transformation of Soil Organic C and Functional Diversity of Soil Microbial Community Under Different Land Uses 被引量:22
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作者 li zhong-pei WU Xiao-chen CHEN Bi-yun 《Agricultural Sciences in China》 CAS CSCD 2007年第10期1235-1245,共11页
Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small water... Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small watershed of subtropical region of China was selected for this study. Land uses covered paddy fields, vegetable farming, fruit trees, upland crops, bamboo stands, and forestry. Soil biological and biochemical properties included soil organic C and nutrient contents, mineralization of soil organic C, and soil microbial biomass and community functional diversity. Soil organic C and total N contents, microbial biomass C and N, and respiration intensity under different land uses were changed in the following order: paddy fields (and vegetable farming) 〉 bamboo stands 〉 fruit trccs (and upland). The top surface (0-15 cm) paddy fields (and vegetable farming) were 76.4 and 80.8% higher in soil organic C and total N contents than fruit trees (and upland) soils, respectively. Subsurface paddy soils (15-30 cm) were 59.8 and 67.3% higher in organic C and total N than upland soils, respectively. Soil microbial C, N and respiration intensity in paddy soils (0-15 cm) were 6.36, 3.63 and 3.20 times those in fruit tree (and upland) soils respectively. Soil microbial metabolic quotient was in the order: fruit trees (and upland) 〉 forestry 〉 paddy fields. Metabolic quotient in paddy soils was only 47.7% of that in fruit tree (and upland) soils. Rates of soil organic C mineralization during incubation changed in the order: paddy fields 〉 bamboo stands 〉 fruit trees (and upland) and soil bacteria population: paddy fields 〉 fruit trees (and upland) 〉 forestry. No significant difference was found for fungi and actinomycetes populations. BIOLOG analysis indicated a changing order of paddy fields 〉 fruit trees (and upland) 〉 forestry in values of the average well cell development (AWCD) and functional diversity indexes of microbial community. Results also showed that the conversion from paddy fields to vegetable farming for 5 years resulted in a dramatic increase in soil available phosphorus content while insignificant changes in soil organic C and total N content due to a large inputs of phosphate fertilizers. This conversion caused 53, 41.5, and 41.3% decreases in soil microbial biomass C, N, and respiration intensity, respectively, while 23.6% increase in metabolic quotient and a decrease in soil organic C mineralization rate. Moreover, soil bacteria and actinomycetes populations were increased slightly, while fungi population increased dramatically. Functional diversity indexes of soil microbial community decreased significantly. It was concluded that land uses in the subtropical region of China strongly affected soil biological and biochemical properties. Soil organic C and nutrient contents, mineralization of organic C and functional diversity of microbial community in paddy fields were higher than those in upland and forestry. Overuse of chemical fertilizers in paddy fields with high fertility might degrade soil biological properties and biochemical function, resulting in deterioration of soil biological quality. 展开更多
关键词 land use patterns transformation of soil organic carbon functional diversity of soil microbial community
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Assembly and co-occurrence patterns of rare and abundant bacterial sub-communities in rice rhizosphere soil under short-term nitrogen deep placement 被引量:2
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作者 li Gui-long WU Meng +5 位作者 li Peng-fa WEI Shi-ping liU Jia JIANG Chun-yu liU Ming li zhong-pei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第12期3299-3311,共13页
Nitrogen(N)deep placement has been found to reduce N leaching and increase N use efficiency in paddy fields.However,relatively little is known how bacterial consortia,especially abundant and rare taxa,respond to N dee... Nitrogen(N)deep placement has been found to reduce N leaching and increase N use efficiency in paddy fields.However,relatively little is known how bacterial consortia,especially abundant and rare taxa,respond to N deep placement,which is critical for understanding the biodiversity and function of agricultural ecosystem.In this study,lllumina sequencing and ecological models were conducted to examine the diversity patterns and underlying assembly mechanisms of abundant and rare taxa in rice rhizosphere soil under different N fertilization regimes at four rice growth stages in paddy fields.The results showed that abundant and rare bacteria had distinct distribution patterns in rhizosphere samples.Abundant bacteria showed ubiquitous distribution;while rare taxa exhibited uneven distribution across all samples.Stochastic processes dominated community assembly of both abundant and rare bacteria,with dispersal limitation playing a more vital role in abundant bacteria,and undominated processes playing a more important role in rare bacteria.The N deep placement was associated with a greater influence of dispersal limitation than the broadcast N fertilizer(BN)and no N fertilizer(NN)treatments in abundant and rare taxa of rhizosphere soil;while greater contributions from homogenizing dispersal were observed for BN and NN in rare taxa.Network analysis indicated that abundant taxa with closer relationships were usually more likely to occupy the central position of the network than rare taxa.Nevertheless,most of the keystone species were rare taxa and might have played essential roles in maintaining the network stability.Overall,these findings highlighted that the ecological mechanisms and co-occurrence patterns of abundant and rare bacteria in rhizosphere soil under N deep placement. 展开更多
关键词 rare bacteria community assembly network analysis co-occurrence patterns N deep placement
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Effects of Glucose Addition on N Transformations in Paddy Soils with a Gradient of Organic C Content in Subtropical China 被引量:2
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作者 JIA Jun-xian li zhong-pei +1 位作者 liU Ming CHE Yu-ping 《Agricultural Sciences in China》 CAS CSCD 2010年第9期1309-1316,共8页
To better understand the interaction of N transformation and exogenous C source and manage N fertilization, the effects of glucose addition on N transformation were determined in paddy soils with a gradient of soil or... To better understand the interaction of N transformation and exogenous C source and manage N fertilization, the effects of glucose addition on N transformation were determined in paddy soils with a gradient of soil organic C content. Changes in N mineralization, nitrification and denitrification, as well as their response to glucose addition were measured by incubation experiments in paddy soils derived from Quaternary red clay in subtropical China. Mineralization and denitrification were changed in order of increasing soil fertilities: high 〉 middle 〉 low. During the first week of incubation, net N mineralization and denitrification rates in paddy soil with high fertility were 1.9 and 1.1 times of those in soil with middle fertility and 5.3 and 2.9 times of those in soil with low fertility, respectively. Addition of glucose decreased net N mineralization by approximately 78.8, 109.2 and 177.4% in soils with high, middle and low fertility, respectively. However, denitrification rates in soils with middle and low fertility were increased by 14.4 and 166.2% respectively. The highest nitrate content among the paddy soils tested was 0.62 mg kg-1 and the highest nitrification ratio was 0.33%. Addition of glucose had no obvious effects on nitrate content and nitrification ratio. It was suggested that the intensity of mineralization and denitrification was quite different in soils with different fertility, and increased with increasing soil organic C content. Addition of glucose decreased mineralization, but increased denitrification, and the shifts were greater in soil with low than in soil with high organic C content. Neither addition of glucose nor inherent soil organic C had obvious effects on nitrification in paddy soils tested. 展开更多
关键词 paddy soils of subtropical China soil fertility glucose addition nitrogen transformation
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自锚式斜拉—悬索协作体系桥的合理成桥状态分析 被引量:7
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作者 李中培 袁明军 +1 位作者 刘孝武 张治成 《公路》 北大核心 2018年第7期132-137,共6页
合理成桥状态是自锚式斜拉—悬索协作体系设计中的关键问题。根据其结构特点,基于Midas Civil专业软件平台,以一座即将建设的斜拉-悬索协作体系——宁波常洪大桥为例,利用主梁和主塔弯矩最小、线形最佳的原则,探讨了一种三步骤迭代分析... 合理成桥状态是自锚式斜拉—悬索协作体系设计中的关键问题。根据其结构特点,基于Midas Civil专业软件平台,以一座即将建设的斜拉-悬索协作体系——宁波常洪大桥为例,利用主梁和主塔弯矩最小、线形最佳的原则,探讨了一种三步骤迭代分析法:首先采用分段弹性悬链线法确定悬索大缆的初始线形及内力,然后耦合斜拉桥结构部分,采用弯曲能量最小法确定斜拉索的初始内力,最后采用优化迭代的方法微调斜拉索和主缆内力以获取协作体系的合理成桥状态。实际工程应用分析结果表明,常洪大桥成桥状态的斜拉索内力分布合理;主梁和桥塔的弯矩应力较小,塔梁基本处于轴压状态;斜—吊混合区主梁弯矩变化平缓;主梁线形平顺;协作体系中跨主梁的弯矩及变形受斜拉索和主缆内力的影响较为敏感。 展开更多
关键词 斜拉-悬索 协作体系 自锚式 合理成桥状态 分析
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