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Effects of long-term fertilization on oxidizable organic carbon fractions on the Loess Plateau,China

Journal of Arid Land 2016年第4期8卷 579-590页

作者： DING shaonan xue sha LIU Guobin College of Natural Resources and Environment Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

The effects of long-term fertilization on pools of soil organic carbon （SOC） have been well studied, but limited information is available on the oxidizable organic carbon （OOC） fractions, especially for the Loess Plateau in China. We evaluated the effects of a 15-year fertilization on the OOC fractions （F1, F2, F3 and F4） in the 0-20 and 20-40 cm soil layers in flat farmland under nine treatments （N （nitrogen, urea）, P （phosphorus, monocalcium phosphate）, M （organic fertilizer, composted sheep manure）, N＋P （NP）, M＋N （MN）, M＋P （MP）, M＋N＋P （MNP）, CK （control, no fertilizer） and bare land （BL, no crops or fertilizer））. SOC content increased more markedly in the treatment containing manure than in those with inorganic fertilizers alone. F1, F2, F4 and F3 accounted for 47%, 27%, 18% and 8% of total organic carbon, respectively. F1 was a more sensitive index than the other C fractions in the sensitivity index （SI） analysis. F1 and F2 were highly correlated with total nitrogen （TN） and available nitrogen （AN）, F3 was negatively correlated with pH and F4 was correlated with TN. A cluster analysis showed that the treatments containing manure formed one group, and the other treatments formed another group, which indicated the different effects of fertilization on soil properties. Long-term fertilization with inorganic fertilizer increased the F4 fraction while manure fertilizer not only increased labile fractions （F1） in a short time, but also increased passive fraction （F4） over a longer term. The mixed fertilizer mainly affected F3 fraction. The study demonstrated that manure fertilizer was recommended to use in the farmland on the Loess Plateau for the long-term sustainability of agriculture.

关键词： long-term fertilization oxidizable organic carbon fractions farmland soil Loess Plateau

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Fractal features of soil profiles under different land use patterns on the Loess Plateau, China

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Journal of Arid Land 2014年第5期6卷 550-560页

作者： Lie XIAO sha xue GuoBin LIU Chao ZHANG State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

Fractal theory is becoming an increasingly useful tool to describe soil structure dynamics for a better understanding of the performance of soil systems. Changes in land use patterns significantly affect soil physical, chemical and biological properties. However, limited information is available on the fractal characteristics of deep soil layers under different land use patterns. In this study, the fractal dimensions of particle size distribution（PSD） and micro-aggregates in the 0–500 cm soil profile and soil anti-erodibility in the 0–10 cm soil profile for 10 typical land use patterns were investigated in the Zhifanggou Watershed on the Loess Plateau, China. The 10 typical land use patterns were： slope cropland, two terraced croplands, check-dam cropland, woodland, two shrublands, orchard, artificial and natural grasslands. The results showed that the fractal dimensions of PSD and micro-aggregates were all significantly influenced by soil depths, land use patterns and their interaction. The plantations of shrubland, woodland and natural grassland increased the amount of larger micro-aggregates, and decreased the fractal dimensions of micro-aggregates in the 0–40 cm soil profile. And they also improved the aggregate state and aggregate degree and decreased dispersion rate in the 0–10 cm soil profile. The results indicated that fractal theory can be used to characterize soil structure under different land use patterns and fractal dimensions of micro-aggregates were more effective in this regard. The natural grassland may be the best choice for improving soil structure in the study area.

关键词： fractal dimension anti-erodibility soil profile land use pattern Loess Plateau

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Effect of Different Vegetation Types on the Rhizosphere Soil Microbial Community Structure in the Loess Plateau of China

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Journal of Integrative Agriculture 2013年第11期12卷 2103-2113页

作者： ZHANG Chao LIU Guo-bin xue sha XIAO Lie State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

The Loess Plateau in China is one of the most eroded areas in the world. Accordingly, vegetation restoration has been implemented in this area over the past two decades to remedy the soil degradation problem. Understanding the microbial community structure is essential for the sustainability of ecosystems and for the reclamation of degraded arable land. This study aimed to determine the effect of different vegetation types on microbial processes and community structure in rhizosphere soils in the Loess Plateau. The six vegetation types were as follows：two natural grassland （Artemisia capillaries and Heteropappus altaicus）, two artificial grassland （Astragalus adsurgens and Panicum virgatum）, and two artificial shrubland （Caragana korshinskii and Hippophae rhamnoides） species. The microbial community structure and functional diversity were examined by analyzing the phospholipid fatty acids （PLFAs） and community-level physiological profiles. The results showed that rhizosphere soil sampled from the H. altaicus and A. capillaries plots had the highest values of microbial biomass C, average well color development of carbon resources, Gram-negative （G-） bacterial PLFA, bacterial PLFA, total PLFA, shannon richness, and shannon evenness, as well as the lowest metabolic quotient. Soil sampled from the H. rhamnoides plots had the highest metabolic quotient and Gram-positive （G＋） bacterial PLFA, and soil sampled from the A. adsurgens and A. capillaries plots had the highest fungal PLFA and fungal：bacterial PLFA ratio. Correlation analysis indicated a signiifcant positive relationship among the microbial biomass C, G- bacterial PLFA, bacterial PLFA, and total PLFA. In conclusion, plant species under arid climatic conditions signiifcantly affected the microbial community structure in rhizosphere soil. Among the studied plants, natural grassland species generated the most favorable microbial conditions.

关键词： soil microbial biomass microbial community structure PLFA community-level physiological profiles,vegetation types

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Soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

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Journal of Integrative Agriculture 2013年第10期12卷 1872-1883页

作者： XIAO Lie LIU Guo-bin xue sha ZHANG Chao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resource

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess *** soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,*** results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly *** shannon richness and shannon evenness of PLFAs significantly increased after 10 yr of ***-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment *** analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community *** soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural ***,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.

关键词： abandoned cropland microbial diversity phospholipid fatty acid(PLFA) redundancy analysis(RDA) Loess Plateau

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Response of Artificial Grassland Carbon Stock to Management in Mountain Region of Southern Ningxia, China

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Chinese Geographical Science 2014年第4期24卷 436-443页

作者： TANG Long DANG Xiaohu LIU Guobin shaO Chuanke xue sha School of Human Settlements and Civil Engineering Xi'an Jiaotong University College of Geology and Environment Xi'an University of Science and Technology State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

Grassland is a major carbon sink in the terrestrial ecosystem. The dynamics of grassland carbon stock profoundly influence the global carbon cycle. In the published literatures so far, however, there are limited studies on the long-term dynamics and influential factors of grassland carbon stock, including soil organic carbon. In this study, spatial-temporal substitution method was applied to explore the characteristics of Medicago sativa L. （alfalfa） grassland biomass carbon and soil organic carbon density （SOCD） in a loess hilly region with different growing years and management patterns. The results demonstrated that alfalfa was the mono-dominant community during the cutting period （viz. 0-10 year）. Community succession began after the abandonment of alfalfa grassland and then the important value of alfalfa in the community declined. The artificial alfalfa community abandoned for 30 years was replaced by the S. bungeana community. Accordingly, the biomass carbon density of the clipped alfalfa showed a significant increase over the time during 0-10 year. During 0-30 year, the SOCD from 0-100 cm of the soil layer of all 5 management patterns increased over time with a range between 5.300 ± 0.981 kg/m2 and 12.578 ± 0.863 kg/m2. The sloping croplands had the lowest SOCD at 5.300 ± 0.981 kg/m2 which was quite different from the abandoned grasslands growing for 30 years which exhibited the highest SOCD with 12.578 ± 0.863 kg/m2. The ecosystem carbon density of the grassland clipped for 2 years increased 0.1 kg/m2 compared with the sloping cropland, while that of the grassland clipped for 10 years substantially increased to 10.30 ± 1.26 kg/m2. Moreover, the ecosystem carbon density for abandoned grassland became 12.62± 0.50 kg/m2 at 30 years. The carbon density of the grassland undisturbed for l0 years was similar to that of the sloping cropland and the grassland clipped for 2 years. Different management patterns imposed great different effects on the accumulation of bio

关键词： artificial Medicago sativa L. (alfalfa) grassland clipped grassland abandoned grassland carbon sink carbon density mountain region southern Ningxia

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Effects of land-use types on the vertical distribution of fractions of oxidizable organic carbon on the Loess Plateau, China

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Journal of Arid Land 2016年第2期8卷 221-231页

作者： SUN Caili xue sha CHAI Zongzheng ZHANG Chao LIU Guobin Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Forestry Northwest A&F University

The oxidizability of soil organic carbon （SOC） influences soil quality and carbon sequestration. Four fractions of oxidizable organic carbon （very labile （C1）, labile （C2）, less labile （C3） and non-labile （C4）） reflect the status and composition of SOC and have implications for the change and retention of SOC. Studies of the fractions of oxidizable organic carbon （OC） have been limited to shallow soil depths and agroecosystems. How these fractions respond at deep soil depths and in other types of land-use is not clear. In this study, we evaluated the vertical distributions of the fractions of oxidizable organic carbon to a soil depth of 5.0 m in 10 land-use types in the Zhifanggou Watershed on the Loess Plateau, China. Along the soil profile, C1 contents were highly variable in the natural grassland and shrubland I （Caragana microphylla）, C2 and C4 contents were highly variable in the natural grassland and two terraced croplands, respectively, and C3 contents varied little. Among the land-use types, natural grassland had the highest C1 and C2 contents in the 0-0.4 m layers, followed by shrubland I in the 0-0.1 m layer. Natural grassland had the highest C4 contents in the 1.0-4.5 m layers. Natural grassland and shrubland I thus contributed to improve the oxidizability of SOC in shallow soil, and the deep soil of natural grassland has a large potential to sequester SOC on the Loess Plateau.

关键词： Iand-use types deep soil oxidizable organic-carbon fractions Loess Plateau

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Receiver-Controlled Multi-Node Cooperation

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 6-12页

作者： Liang Ye Yue Li xue-Jun sha Esko Alasaarela Communication Research Center Harbin Institute of Technology Dept. of Electrical Engineering University of Oulu

Since wireless links in Ad hoc networks are more fragile than those in traditional wireless networks due to route flapping,multi-node cooperation plays an important role in ensuring the quality of service( QoS). Based on the authors' previous work,this paper proposes a receiver-controlled multi-node cooperation routing protocol,known as AODV-RCC. In this protocol,nodes form a cooperation group based on signal power. In a cooperation group,signal power between a partner and a transmitter,as well as signal power between the partner and the receiver,must be larger than the signal power between the transmitter and the receiver. Otherwise,the transmission will not benefit from cooperation. To avoid collision or congestion,each cooperation group only contains one partner. This partner offers both data and ACK cooperative retransmission. Its retransmission time should be shorter than the internal retry time of the transmitter's MAC layer,because it is better for the partner to retransmit firstly,as it offers a more reliable cooperative link. In AODV-RCC,it is the receiver that chooses the partner,because the link between the partner and the receiver is the most important. According to our simulation results,AODV-RCC shortens the end-to-end delay and increases the packet delivery ratio.

关键词： multi-node cooperation receiver-controlled routing protocol Ad hoc network

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Soil legacy effects and plant-soil feedback contribution to secondary succession processes

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Soil Ecology Letters 2023年第2期5卷 117-125页

作者： Qing Qu Hongwei Xu Guobin Liu sha xue State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China University of Chinese Academy of Sciences Beijing 100049China

Secondary succession is the process by which a community develops into a climax community over ***,knowledge on the mechanisms,relating to soil legacy effects(soil chemistry and enzyme activity)and plant-soil feedback(PSF),driving community succession remains *** this work,we examined the PSF associated with three succession stage species through a 2-year greenhouse *** viridis,Stipa bungeana,and Bothriochloa ischemum were selected to represent dominant and representative early-,mid-,and late-successional stage species,respectively,of semiarid grasslands on the Loess *** response to the different soil origin,the shoot biomass of early-,mid-,and late-species were all higher when grown in their own soil than in other species’soils,which indicated that the PSF of three species were *** two growth periods,the early-species experienced a negative PSF,but the mid-and late-species experienced negative,neutral and positive PSF in the soil of early-,mid-and late-species,*** study demonstrates that soil legacy effects and PSF have a significant impact on community succession processes.

关键词： Grassland Plant growth Plant-soil feedback Soil microbial activity Soil legacy effects Secondary succession

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Activity Enhancement of Pt/Ba/Al_(2)O_(3) Mixed with Mn/Ba/Al_(2)O_(3) for NO_(x) Storage-reduction by Hydrogen

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Chinese Chemical Letters 2006年第10期17卷 1357-1360页

作者： Jian Hua XIAO xue Hui LI sha DENG Fu Rong WANG Le Fu WANG School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640

Abstract： Mn/Ba/Al2O3 catalyst for NO oxidation-storage and Pt/Ba/Al2O3 catalyst mixed with Mn/Ba/Al2O3 for NOx storage-reduction by hydrogen were investigated. The results showed that Mn/Ba/Al2O3 had large nitrogen oxides storage capacity （397.9 μmolg^-1） under lean burn condition. When Pt/Ba/Al2O3 catalyst was mixed with Mn/Ba/Al2O3 in equal weight proportion, the NOx conversion increased between 250 ℃ and 500 ℃ under the dynamic lean-rich burn conditions, and the maximum NOx conversion increased from 95.4% to 98.2%. Mn/Ba/Al2O3 has promoted NOx storing in the lean stage and improved NOx reduction efficiency in the rich stage, these might result in higher NOx conversion over the low Pt loading content catalyst.

关键词： Nitrogen oxides storage-reduction lean burn Pt/Ba/Al2O3 Mn/Ba/Al2O3

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薛莎治疗更年期失眠经验

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中医药临床杂志 2018年第1期30卷 53-55页

作者：孙敏薛莎湖北中医药大学湖北武汉430065 湖北省武汉市中西医结合医院湖北武汉430022

近年来,临床上更年期失眠的患者越来越多,严重影响患者的身心健康及生活质量。论文总结了导师薛莎教授对更年期失眠的病机分析、辨证分型和谴方用药等方面的独到见解。

关键词：更年期失眠薛莎临床经验

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