Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Li...Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Linn.) O. Ktze. f., P_4), oleander (Nerium indicum Mill,P_5), rape (Brassica campestris L., P_g), Chinese tallow tree (Sapium sebiferum L., P_7), tung(Vernicia fordii (Hemsl.), P_8), and croton (Croton tiglium L., P_9), 7 chemicals, boric acid (C_1),borax (C_2), oxalic acid (C_3), sodium oxalite (C_4), sodium dihydrogen phosphate (C_6), sodiumsilicate (C_7) and sodium citrate (C_8), and a natural organic substance, humic acid (C_5), onurease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied throughincubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. Afterincubation at 37℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity wereselected and then incubated for 14 days at 25℃. Results of the incubation experiments showed thatsoil urease activity was greatly inhibited by them, and the inhibition effect followed an order ofP_2>P_4>C_3>C_2>P_3>C_1>HQ>P_1. The 7 selected materials reduced the accumulative amounts of Nreleased from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively,and postponed the N release peak by 2~4 days in the incubation period of 14 days under constanttemperature, as compared to the control (no inhibitor). In the pot experiment with the 7 materialsat two levels of addition, low (L) and high (H), the C_1 (H), C_3 (H), C_1 (L), P_4 (L) and C_2 (L)treatments could significantly increase the dry weights of the aboveground parts and the totalbiomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% ascompared to the control (no hibitor).展开更多
Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soi...Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soil resources distributed differently in different locations, and present significant spatial heterogeneity in desert ecosystems. In this study, conventional and geostatistical methods were used to identify the heterogeneity of soil chemical properties in two desert populations, Haloxylon persicum Bunge ex Boss., which dominates on the slopes and tops of sand dunes and Haloxylon ammodendron (C. A. Mey.) Bunge, which inhabits interdunes in the Gurbantunggut Desert of Xinjiang, China. The results showed that soil pH, electrical conductivity (EC), soil organic carbon (SOC), available nitrogen (AN) and available phosphorus (AP) were significantly higher in H. ammodendron populations than that in H. persicum. The coefficient of variation (CV) indicated that (1) most parameters presented a moderate degree of variability (10% 【 CV 【 100%) except pH in both plots, (2) the variability of soil pH, EC and AP in H. ammodendron populations was higher than that in H. persicum populations, and (3) SOC and AN in H. ammodendron populations were lower than that in H. persicum populations. Geostatistical analysis revealed a strong spatial dependence (C0/(C0+C) 【 25%) within the distance of ranges for all tested parameters in both plots. The Kriging-interpolated figures showed that the soil spatial distribution was correlated with the vegetation distribution, individual size of plants, and the topographic features, especially with the plants nearest to sampling points and the topographic features. In each plot, soil EC, SOC, AN and AP presented similar distributions, and fertile islands and salt islands occurred in both plots but did not affect every individual plant, since the sampling distance was larger than the size of such fertile islands. The results of topographic effects on soil heterogeneity suggested significant differences between the interdunes and dune-tops. Different topographic characteristics (physical factors) between plots result in the differences in SOC, AN and AP, while the heterogeneity of soil pH and EC arise from plant species and their distribution (biotic factor). Such biotic and physical factors did not occur in isolation, but worked together on soil heterogeneity, and played important parts in improving the soil properties. Hence these factors were ecologically valuable in the highly resource-stressed arid study area.展开更多
The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fr...The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fractions it can be used in the next growth season,possibly decreasing plant dependence on P derived from soil fertilization.However,if P is preferentially accumulated in inorganic fractions in annual organs,plants will be more dependent on phosphate fertilization.This study aimed to evaluate the distribution of P fractions in organs of C.trichotoma grown on sandy soil treated with 120 and 360 kg P2O5 ha^(−1).The control was a zero application.After 24 months following fertilization,C.trichotoma seedlings were cut and separated into leaves,branches,stems and roots,dried,ground and subjected to chemical fractionation of P,which estimates fractions of total soluble P,soluble inorganic and organic P,lipid P,P associated ribonucleic acid and deoxyribonucleic acid,and residual P.P in annual organs,as leaves,accumulated preferentially in the soluble inorganic fraction in both treatments.In perennial organs such as stems and branches,P accumulated preferentially in the soluble organic fraction.The application of 300%of the recommended dosage(360 kg P2O5 ha^(−1))promoted the accumulation of P in soluble organic fractions which may contribute to annual growth the following season and be a strategy to reduce the dependence of 2-year-old stands on soil-derived P and on fertilizers.展开更多
有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M...有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M)和有机肥替代100%化肥氮(100%M) 6个处理,研究不同替代率对谷子产量构成和氮素吸收的影响,并分析氮素吸收调控小米米色、糊化特性和类胡萝卜素组分的效应,明确谷子生产中有机肥最佳替代率。结果表明,2年中较低的有机肥替代化肥氮率显著提高了谷子植株氮素累积,但随着替代率的持续增加,植株氮素累积量呈降低趋势,最终影响谷子产量和小米品质。2020年, 25%M处理显著提高了谷子地上部氮素累积量,较NPK处理提高9.6%;2021年,25%M处理谷子地上部氮素累积量、生物量、穗粒数和产量达到最高,较NPK处理分别提高6.1%、12.0%、15.4%和12.0%。50%M处理显著影响了小米的米色、糊化特征和类胡萝卜素含量,与NPK相比,小米籽粒红绿值、橘色值、支链淀粉含量、总淀粉含量、小米糊化最终黏度、叶黄素含量、玉米黄质含量和黄色素含量的增幅分别可达6.0%、6.0%、7.4%、4.3%、7.8%、20.7%、17.4%和2.8%。但有机肥完全替代化肥降低了谷子地上部氮素吸收、地上部生物量、穗粒数及谷子产量,也抑制了小米叶黄素和玉米黄质含量的提升。2年均表现出谷子地上部氮吸收量与小米单粒重、直链淀粉含量和小米糊化回升值呈显著的负相关。且2021年谷子地上部氮吸收量还与小米总淀粉含量、蛋白质含量、小米粉糊化峰值黏度和小米黄色素含量呈显著的负相关,与小米糊化峰谷黏度呈显著的正相关。综上,施氮总量120 kg hm^(–2)下,有机肥替代25%~50%化肥氮能通过促进植株氮素的吸收,实现产量、米色、蒸煮特性及类胡萝卜素的协同提升,为谷子化肥减量和提质增效生产提供技术支撑。展开更多
利用从烤烟根际筛选的抗生菌、固氮菌、解磷菌和解钾菌菌株制成PGPR菌肥,进行田间完全区组随机试验,研究其在减施化肥的条件下对烤烟产量质量的影响。试验地土壤类型为黄棕壤,种植烤烟品种为云烟89,菌肥施用量30 kg hm-2,于烤烟移栽时...利用从烤烟根际筛选的抗生菌、固氮菌、解磷菌和解钾菌菌株制成PGPR菌肥,进行田间完全区组随机试验,研究其在减施化肥的条件下对烤烟产量质量的影响。试验地土壤类型为黄棕壤,种植烤烟品种为云烟89,菌肥施用量30 kg hm-2,于烤烟移栽时溶于生根水中一起施入。共设4个处理,分别是(1)常规施肥同时施用PGPR菌肥;(2)NPK肥为常规施肥的80%同时施用PGPR菌肥;(3)常规施肥;(4)NPK肥为常规施肥的80%。结果表明,施用菌肥的二处理与未施用菌肥的二处理相比,施用菌肥不同生长期烤烟根际放线菌的数量显著降低17%~27%(p<0.05),根际微生物生物量碳含量提高3%~16%,现蕾期根际解磷菌的数量显著提高24%(p<0.05),并可提高烤烟的抗病性,烤后烟外观质量好。处理(2)与处理(4)比较,现蕾期烤烟根际氮、钾、铜、锌、硼和铁6种元素的有效性提高4.46%~28.87%,而磷、钙、镁和锰4种矿质元素的有效性降低2.63%~30.19%,烤烟产量和净产值分别提高7.53%和30.05%。处理(2)与处理(3)比较,烤烟产量和净产值分别提高4.52%和24.68%。使用PGPR菌肥可适当减少化肥用量,为可持续生产优质、无公害烟叶的有效途径之一。展开更多
基金the Laboratory of Material Cycling in Pedosphere,the Chinese Academy of Sciences the Chongqing Science and Technology Commission,China.
文摘Effects of residues of 9 plants, lemon eucalyptus (Eucalyptus citriodoraHook., P_1), robust eucalyptus (E. robusta Smith, P_2), Nepal camphortree (Cinnamomum glanduliferum(Wall.) Nees, P_3), tea (Camellia sinensis (Linn.) O. Ktze. f., P_4), oleander (Nerium indicum Mill,P_5), rape (Brassica campestris L., P_g), Chinese tallow tree (Sapium sebiferum L., P_7), tung(Vernicia fordii (Hemsl.), P_8), and croton (Croton tiglium L., P_9), 7 chemicals, boric acid (C_1),borax (C_2), oxalic acid (C_3), sodium oxalite (C_4), sodium dihydrogen phosphate (C_6), sodiumsilicate (C_7) and sodium citrate (C_8), and a natural organic substance, humic acid (C_5), onurease activity of a neutral purple soil and recovery of urea nitrogen by maize were studied throughincubation and pot experiments. Hydroquinone (HQ) was applied as the reference inhibitor. Afterincubation at 37℃ for 24 h, 7 inhibitors with higher ability to inhibit urease activity wereselected and then incubated for 14 days at 25℃. Results of the incubation experiments showed thatsoil urease activity was greatly inhibited by them, and the inhibition effect followed an order ofP_2>P_4>C_3>C_2>P_3>C_1>HQ>P_1. The 7 selected materials reduced the accumulative amounts of Nreleased from urea and the maximum urease activity by 11.7%~28.4% and 26.7%~39.7%, respectively,and postponed the N release peak by 2~4 days in the incubation period of 14 days under constanttemperature, as compared to the control (no inhibitor). In the pot experiment with the 7 materialsat two levels of addition, low (L) and high (H), the C_1 (H), C_3 (H), C_1 (L), P_4 (L) and C_2 (L)treatments could significantly increase the dry weights of the aboveground parts and the totalbiomass of the maize plants and the apparent recovery rate of urea-N was increased by 6.3%~32.4% ascompared to the control (no hibitor).
基金supported by the National Natural Science Foundation of China (40701187)the Western Light Project of the Chinese Academy of Sciences (XBBS200808)
文摘Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soil resources distributed differently in different locations, and present significant spatial heterogeneity in desert ecosystems. In this study, conventional and geostatistical methods were used to identify the heterogeneity of soil chemical properties in two desert populations, Haloxylon persicum Bunge ex Boss., which dominates on the slopes and tops of sand dunes and Haloxylon ammodendron (C. A. Mey.) Bunge, which inhabits interdunes in the Gurbantunggut Desert of Xinjiang, China. The results showed that soil pH, electrical conductivity (EC), soil organic carbon (SOC), available nitrogen (AN) and available phosphorus (AP) were significantly higher in H. ammodendron populations than that in H. persicum. The coefficient of variation (CV) indicated that (1) most parameters presented a moderate degree of variability (10% 【 CV 【 100%) except pH in both plots, (2) the variability of soil pH, EC and AP in H. ammodendron populations was higher than that in H. persicum populations, and (3) SOC and AN in H. ammodendron populations were lower than that in H. persicum populations. Geostatistical analysis revealed a strong spatial dependence (C0/(C0+C) 【 25%) within the distance of ranges for all tested parameters in both plots. The Kriging-interpolated figures showed that the soil spatial distribution was correlated with the vegetation distribution, individual size of plants, and the topographic features, especially with the plants nearest to sampling points and the topographic features. In each plot, soil EC, SOC, AN and AP presented similar distributions, and fertile islands and salt islands occurred in both plots but did not affect every individual plant, since the sampling distance was larger than the size of such fertile islands. The results of topographic effects on soil heterogeneity suggested significant differences between the interdunes and dune-tops. Different topographic characteristics (physical factors) between plots result in the differences in SOC, AN and AP, while the heterogeneity of soil pH and EC arise from plant species and their distribution (biotic factor). Such biotic and physical factors did not occur in isolation, but worked together on soil heterogeneity, and played important parts in improving the soil properties. Hence these factors were ecologically valuable in the highly resource-stressed arid study area.
基金financed in part by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq)the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)。
文摘The application of phosphorus(P)to soil can increase its availability to plants and alter P fractions in annual and perennial organs of Cordia trichotoma.If a portion of P accumulates in perennial organs in organic fractions it can be used in the next growth season,possibly decreasing plant dependence on P derived from soil fertilization.However,if P is preferentially accumulated in inorganic fractions in annual organs,plants will be more dependent on phosphate fertilization.This study aimed to evaluate the distribution of P fractions in organs of C.trichotoma grown on sandy soil treated with 120 and 360 kg P2O5 ha^(−1).The control was a zero application.After 24 months following fertilization,C.trichotoma seedlings were cut and separated into leaves,branches,stems and roots,dried,ground and subjected to chemical fractionation of P,which estimates fractions of total soluble P,soluble inorganic and organic P,lipid P,P associated ribonucleic acid and deoxyribonucleic acid,and residual P.P in annual organs,as leaves,accumulated preferentially in the soluble inorganic fraction in both treatments.In perennial organs such as stems and branches,P accumulated preferentially in the soluble organic fraction.The application of 300%of the recommended dosage(360 kg P2O5 ha^(−1))promoted the accumulation of P in soluble organic fractions which may contribute to annual growth the following season and be a strategy to reduce the dependence of 2-year-old stands on soil-derived P and on fertilizers.
文摘有机肥部分替代化肥是一种实现化肥减量的可持续农业生产措施。本研究于2020和2021连续2年以“沁黄2号”为供试材料,设不施氮(CK)、常量化肥氮(NPK)、有机肥替代25%化肥氮(25%M)、有机肥替代50%化肥氮(50%M)、有机肥替代75%化肥氮(75%M)和有机肥替代100%化肥氮(100%M) 6个处理,研究不同替代率对谷子产量构成和氮素吸收的影响,并分析氮素吸收调控小米米色、糊化特性和类胡萝卜素组分的效应,明确谷子生产中有机肥最佳替代率。结果表明,2年中较低的有机肥替代化肥氮率显著提高了谷子植株氮素累积,但随着替代率的持续增加,植株氮素累积量呈降低趋势,最终影响谷子产量和小米品质。2020年, 25%M处理显著提高了谷子地上部氮素累积量,较NPK处理提高9.6%;2021年,25%M处理谷子地上部氮素累积量、生物量、穗粒数和产量达到最高,较NPK处理分别提高6.1%、12.0%、15.4%和12.0%。50%M处理显著影响了小米的米色、糊化特征和类胡萝卜素含量,与NPK相比,小米籽粒红绿值、橘色值、支链淀粉含量、总淀粉含量、小米糊化最终黏度、叶黄素含量、玉米黄质含量和黄色素含量的增幅分别可达6.0%、6.0%、7.4%、4.3%、7.8%、20.7%、17.4%和2.8%。但有机肥完全替代化肥降低了谷子地上部氮素吸收、地上部生物量、穗粒数及谷子产量,也抑制了小米叶黄素和玉米黄质含量的提升。2年均表现出谷子地上部氮吸收量与小米单粒重、直链淀粉含量和小米糊化回升值呈显著的负相关。且2021年谷子地上部氮吸收量还与小米总淀粉含量、蛋白质含量、小米粉糊化峰值黏度和小米黄色素含量呈显著的负相关,与小米糊化峰谷黏度呈显著的正相关。综上,施氮总量120 kg hm^(–2)下,有机肥替代25%~50%化肥氮能通过促进植株氮素的吸收,实现产量、米色、蒸煮特性及类胡萝卜素的协同提升,为谷子化肥减量和提质增效生产提供技术支撑。
文摘利用从烤烟根际筛选的抗生菌、固氮菌、解磷菌和解钾菌菌株制成PGPR菌肥,进行田间完全区组随机试验,研究其在减施化肥的条件下对烤烟产量质量的影响。试验地土壤类型为黄棕壤,种植烤烟品种为云烟89,菌肥施用量30 kg hm-2,于烤烟移栽时溶于生根水中一起施入。共设4个处理,分别是(1)常规施肥同时施用PGPR菌肥;(2)NPK肥为常规施肥的80%同时施用PGPR菌肥;(3)常规施肥;(4)NPK肥为常规施肥的80%。结果表明,施用菌肥的二处理与未施用菌肥的二处理相比,施用菌肥不同生长期烤烟根际放线菌的数量显著降低17%~27%(p<0.05),根际微生物生物量碳含量提高3%~16%,现蕾期根际解磷菌的数量显著提高24%(p<0.05),并可提高烤烟的抗病性,烤后烟外观质量好。处理(2)与处理(4)比较,现蕾期烤烟根际氮、钾、铜、锌、硼和铁6种元素的有效性提高4.46%~28.87%,而磷、钙、镁和锰4种矿质元素的有效性降低2.63%~30.19%,烤烟产量和净产值分别提高7.53%和30.05%。处理(2)与处理(3)比较,烤烟产量和净产值分别提高4.52%和24.68%。使用PGPR菌肥可适当减少化肥用量,为可持续生产优质、无公害烟叶的有效途径之一。