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Viscoelasticity and shear resistance at the aggregate scale of structured and organic carbon-free Chernozems

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Pedosphere 2023年第5期33卷 754-764页

作者： Christoph HAAS Rainer HORN Philipp SAGGAU Rainer DUTTMANN institute for Plant Nutrition and Soil Science University of KielKiel 24118Germany Department of Geography Division of Landscape Ecology and Geoinformation SciencesUniversity of KielKiel 24118Germany

Soil rheology characterises the flow behaviour of soils at the particle-particle to aggregate *** sweep tests(ASTs)are often the method of choice for parameterizing soil flow properties,such as the shear strain values at the end of the linear viscoelastic range(i.e.,the deformation is mainly elastic)and at the yield point(i.e.,elastic equals plastic deformation).Samples from seven soil profiles and five soil depths of Chernozems,collected in the Maidanetske study area,close to Uman City of Ukraine,were analysed to evaluate the effect of soil organic carbon(SOC)on the parameters related to soil microstructural stability derived from *** organic carbon was removed with H_(2)O_(2)to determine the soil texture-dependent values of soil rheological properties,which were compared to the values determined for samples with intact water-stable *** shear resistance-related parameters increased for aggregated soil samples compared to SOC-free soil samples,indicating an increase in soil stability due to *** contrast,the values of the overall viscoelasticity and the shear strain were reduced for aggregated soil samples,indicating decreased soil *** functions were applied to predict the shear strain-dependent loss and storage moduli and shear stress values as a function of SOC *** particles(630–2000μm)and volumetric water content improved the *** conclude that increased SOC content,through the gluing and cementing effects of SOC and altered aggregate shapes compared to SOC-free soil materials,contributes to higher microstructural ***,the increased water content in the SOC-containing soil samples reversed soil strengthening *** was due to the fact that a more rapid increase in positive water pressure under shear stress weakened the samples and the spherical aggregates began to rotate more easily,thus loosing energy,when compared to platy particles of the SOC-free soil materials.

关键词： aggregation rheology shear strain shear stress soil organic carbon depletion soil stability

Differences in Organic C Mineralization Between Aerobic and Submerged Conditions in Paddy Soils of Southern Jiangsu Province,China

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Agricultural Sciences in China 2011年第9期10卷 1410-1418页

作者： HAO Rui-jun LI Zhong-pei CHE Yu-ping State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R. China Shanghai institute of landscape Gardening Shanghai 200232 P.R.China

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.

关键词： moisture regime paddy soil SOC mineralization aerobic condition submerged condition difference

landscape Design of Colleges and Universities Based on Low Impact Concept: A Case Study of the Shared Training Base from Jiangsu Vocational institute of Architectural Technology

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Journal of landscape Research 2018年第4期10卷 21-24页

作者： XING Hongtao School of Architectural Design and Decoration Jiangsu Vocational Institute of Architectural Technology

In recent years, the acceleration of urbanization process results in frequent watedoggingj the decline of groundwater level and frequent urban infiasttucture construction pfoblem. In order to better safeguard complex ecological system and ecological civilization construction in tiie city, and solve the appropriate ratio of water and wetland area to total land area, for water ecological civilization construction in low impact development, the pursuit of water resources sustainability, the pursuit of safety concept, the pursuit of ecological engineeting technology and the pursuit of art are proposed. Based on these pursuits, the principles and design methods of campus landscape creation in colleges and univefsities under the concept of elow impact^ is analyzed. Taking the landscape design, of the shated training base from Jiangsu Vocational institute of Architectural Technology as an example, how to use the concept of clow impacf？ development in actual cases is analyze4 to achieve rainwater collection, water purification, water storage and rainwater ecological utilization, and create a holistic, ecological and diverse sustainable landscape in colleges and universities.

关键词： Low impact Colleges and universities landscape design Ecology Eneigy saving

Prediction of nitrogen and phosphorus contents in citrus leaves based on hyperspectral imaging

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International Journal of Agricultural and Biological Engineering 2015年第2期8卷 80-88页

作者： Liu Yanli Lyu Qiang He Shaolan Yi Shilai Liu Xuefeng Xie Rangjin Zheng Yongqiang Deng Lie College of Horticulture and landscape Southwest UniversityBeibeiChongqing 400715China Citrus Research institute Southwest University-Chinese Academy of Agricultural SciencesBeibeiChongqing 400712China

The nutritional status of citrus leaves is very important to the determining of fertilization *** spectrum technique is a quick,un-injured method and is becoming widely used for plant nutrient *** possibility and method of using spectrum technique to estimate the nutrient of citrus leaf was explored in this study.A total amount of 135 leaves from the mature spring shoots of navel orange trees(*** Osbeck,“Newhall”)were collected and randomly grouped into two sets of samples:100 leaves for the calibration set and 35 leaves for the prediction *** hyperspectral images were scanned upper and lower side of each leaf and then the total nitrogen(N)and phosphorus(P)contents of each leaf were *** raw spectra data were extracted to generate average spectra curves,preprocessed with five different methods,and was used to build N and P content prediction *** performances of the five preprocessing methods,i.e.,Savitzky-Golay smoothing(SGS),standard normal variate(SNV),multiplicative scatter correction(MSC),first-derivative(1-Der)and second-derivative(2-Der),were tested with linear partial least squares(PLS)models and nonlinear least squares-support vector machine(LS-SVM)*** results showed that the SG-PLS and PLS were the best for the N predicting(Rp=0.9049,RMSEP=0.1041)and P(Rp=0.9235,RMSEP=0.0514)in citrus leaves,respectively;the hyperspectral image data from leaf‟s upper side predicting better for the contents of N and *** study suggested that the hyperspectral image data from the upper side of the citrus leaves are suitable for nondestructive estimation of nutrient content.

关键词： citrus leaves nitrogen phosphorus prediction hyperspectral imaging

Drying conditions in Switzerland-indication from a 35-year Landsat time-series analysis of vegetation water content estimates to support SDGs

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Big Earth Data 2021年第4期5卷 445-475页

作者： Charlotte Poussin Alexandrine Massot Christian Ginzler Dominique Weber Bruno Chatenoux Pierre Lacroix Thomas Piller Liliane Nguyen Gregory Giuliani institute for Environmental Sciences University of GenevaGenevaSwitzerland Swiss Federal institute for Forest Snow and Landscape Research WSLBirmensdorfSwitzerland institute for Environmental Sciences Gap Non-linearity and Climate GroupUniversity of GenevaGenevaSwitzerland

Exacerbated by climate change,Europe has experienced series of hot and dry summer since the beginning of the 21st *** importance of land conditions became an international concern with a dedicated sustainable development goal(SDG),the SDG *** calls for developing and finding innovative solu-tions to follow and evaluate impacts of changing land condi-tions induced by various driving *** Switzerland,drought risk will significantly increase in the coming decades with severe consequences on agriculture,energy production and *** this paper,we used a 35-year satellite-derived annual and seasonal times-series of normalized difference water index(NDWI)to follow vegetation water content evolution at different spatial and temporal scales across Switzerland and related them to temperature and precipitation to investigate possible responses of changing climatic *** indicate that there is a small and slow drying tendency at the country scale with a NDWI mean decreasing slope of−0.22%/year for the 23%significant pixels across *** tendency is mostly visible below 2000 m above sea level(m.a.s.l.)and in all biogeographical *** Southern Alps regions appear to be more responsive to changing drying conditions with a significant and slight negative NDWI trend(−0.39%/year)over the last 35 ***,NDWI values are mostly a func-tion of temperature at elevations below the tree line rather than *** suggest that multi-annual and seasonal NDWI can be a valuable indicator to monitor vegetation water content at different scales,but other components such as land cover type and evapotranspiration should be considered to better characterize NDWI *** Earth Observations data can provide valuable complementary obser-vations for national statistics on the ecological state of vegeta-tion to support SDG 15 to monitor land affected by drying conditions.

关键词： Climate change vegetation NDWI Landsat drought SDG 15 land degradation ecosystems Earth Observation big Earth data Switzerland

“City-Scene” Characteristics and Optimization Strategies Research on Three Gorges Reservoir Area of the Post-Three Gorges Era

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Journal of landscape Research 2017年第1期9卷 8-14页

作者： LIAO Congquan LUO Ping Chongqing landscape Architecture Planning institute College of landscape Architecture Chongqing University

In the long-term symbiotic evolution process,the town areas along the Yangtze River and its natural and cultural landscapes have presented a sound "city-scene" landscape form. But with the implementation of the Three Gorges project,the town relocation as well as the flooding in the natural and human landscape area,the original harmonious "city-scene" pattern started to collapse and fell into the situation of "fragmentation" and "islanding". The differentiation between city and landscape,uncoordinated scale and fractured urban context become pressing issues that affect the integral form optimization of the town areas. This paper aims at responding to the call of the government about proceeding the construction of the Yangtze River economic belt under the ecological and green strategy and seeking an attuned "cityscene" relationship of the town area. Based on the analysis of the dynamic evolution of the "city-scene" relationship,the paper also pointed out that the urban construction around the reservoir area in the postThree Gorges era was the key stage of "scene-city" integration and symbiosis while the maintenance of scenery pattern,the harmony of space scale and the protection of living culture should be applied as the vital strategies.

关键词： Town areas of the Three Gorges Reservoir City-scene relationship Cultural landscape Town form optimization

Isolation,expression and single nucleotide polymorphisms(SNPs) analysis of LACCASE gene(LkLAC8) from Japanese larch(Larix kaempferi)

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Journal of Forestry Research 2017年第5期28卷 891-902页

作者： Changyong Liu Yunhui Xie Min Yi Shougong Zhang Xiaomei Sun State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of Forestry Research institute of Forestry Chinese Academy of Forestry State Academy of Forestry Administration School of Gardening and landscape Design Jiangxi Agricultural University

Nucleotide diversity (pi) and linkage disequilibrium (LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method. Japanese larch (Larix kaempferi) is an important timber coniferous tree species for pulping and papermaking, but its high lignin content has significantly restricted it application potential. In this study, the LACCASE gene, that plays an important regulatory role for lignin biosynthesis, was selected as research target. The full-length cDNA and genomic sequences of the encoding LkLAC8 gene were isolated from the LACCASE expressed sequence tags of the Japanese larch transcriptome database using the rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA was determined to be 1940 bp, with an open reading frame (ORF, 1734 bp) that encoded a protein of 577 AA. This protein contains four highly specific Cu2+ binding sites and 11 glycosylation sites, thus belonging to the LACCASE family. The deduced protein sequence shared an 89% identity with the PtaLAC from Pinus taeda. A real-time PCR analysis showed that the LkLAC8 transcript was expressed predominantly in mature xylem, with moderate levels in the immature xylem, cambium and mature leaves, the lowest in the roots. Lastly, the genomic sequences of LkLAC8 in 40 individuals from six naturally distributed populations of Japanese larch were amplified, and a total of 201 SNPs (103 and 98 mutation types of transition and transversion, respectively) were detected; the frequency of the SNPs was 1/19 bp. Nucleotide diversity among the six populations ranged from 0.0034 to 0.0053, which suggested that there were no significant differences among the populations. The LD analysis showed that the LD level decayed rapidly within the increasing length of the LkLAC8 gene. These results implied that LD mapping and association analysis based on candidate gene may be feasible for the marker-assisted breeding of new germplasms with low lignin in Japanese lar

关键词： Gene cloning LACCASE Larix kaempferi Linkage disequilibrium Real-time PCR Single nucleotide polymorphisms

Migration phenology determines niche use of East Asian buntings (Emberizidae)during stopover

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Current Zoology 2018年第6期64卷 681-692页

作者： Wieland HEIM Jana A.ECCARD Franz BAIRLEIN institute of landscape Ecology Munster UniversityHeisenbergstraβe 2Munster48149Germany Animal Ecology Institute of Biology and BiochemistryUniversitat PotsdamMaulbeerallee 1Potsdam14469Germany institute of Avian Research "Vogelwarte Helgoland" An der Vogelwarte 21Wilhelmshaven28386Germany

Stopover niche utilization of birds during migration has not gained much attention so far,since the majority of the studies focuses on breeding or wintering ***,stopover sites are crucial for migratory *** are often used by a multitude of species,which could lead to increased *** this work,we investigated niche use of 8 migratory and closely related Emberiza bunting species at a stopover site in Far East Russia,situated on the poorly studied East Asian *** used bird ringing data to evaluate morphological similarity as well as niche overlap on the trophic,spatial,and temporal *** morphology was used as a proxy for their trophic *** were able to prove that a majority of the species occupies well-defined stopover niches on at least one of the *** breadth and niche overlap differ between spring and autumn season with higher overlap found during *** differences are mostly related to overall size and wing *** temporal dimension is most important for segregation among the studied ***,all species seem to exhibit a rather strict and consistent phenological *** occurrence at the study site is highly correlated with their geographic origin and the length of their migration *** assume that buntings are able to use available resources opportunistically during stopover,while trying to follow a precise schedule in order to avoid competition and to ensure individual fitness.

关键词： bird migration Emberiza habitat use non-breeding phenology stopover

Changes in foliar nitrogen resorption of Phyllostachys edulis with culm development

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Journal of Forestry Research 2019年第2期30卷 417-427页

作者： Changshun Zhang Chunlan Liu Wenyuan Zhang Gaodi Xie Shaohui Fan Na Li institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing Municipal Research institute of Environmental Protection College of landscape and Art Jiangxi Agricultural University International Centre for Bamboo and Rattan University of Chinese Academy of Sciences

Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing ***, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in *** stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm *** nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.

关键词： Phyllostachys edulis Nitrogen resorption efficiency Nitrogen resorption proficiency Nitrogen-use efficiency Extensive management Culm development Precision fertilization