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| 1 | The effect of land use structure on the distribution of soil nutrients in the hilly area of the Loess Plateau,China显示文摘The irrational land use is one of the main reasons for the soil erosion and nutrient loss in the loess hilly area of China. In this project, 4 types of typical land use structure of sustain ment for about 15 years in the loess hill slope are selected to study the effect of land use structure on the distribution of soil nutrients. From hill bottom to hill top, the patterns of land use types are:, grassland-slope farmland-forest, slope farmland-grassland-forest, terrace-grassland-forest and slope farmland-forest-grassland. By measuring the contents of the total N, total P, available N, available P and organic matter of soils, the results show that the land use structure types of slope farmland-grassland-forest and terrace-grassland-forest have a better capacity to maintain the soil nutrients. | Bojie Fu Keming Ma Huafeng Zhou Liding Chen | 1999 | Chinese Science Bulletin1999，44，8： | 32 |
| 2 | Soil microbial properties under different vegetation types on Mountain Han显示文摘This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China.Soil samples were taken at 0-5,5-10 and 10-20 cm depths from four vegetation types at different altitudes,which were characterized by poplar(Populus davidiana)(1250-1300 m),poplar(P.davidiana) mixed with birch(Betula platyphylla)(1370-1550 m),birch(B.platyphylla)(1550-1720 m),and larch(Larix principis-rupprechtii)(1840-1890 m).Microbial biomass and community structure were determined using the fumigation-extraction method and phospholipid fatty acid(PLFA) analysis,and soil fungal community level physiological profiles(CLPP) were characterized using Biolog FF Microplates.It was found that soil properties,especially soil organic carbon and water content,contributed significantly to the variations in soil microbes.With increasing soil depth,the soil microbial biomass,fungal biomass,and fungal catabolic ability diminished;however,the ratio of fungi to bacteria increased.The fungal ratio was higher under larch forests compared to that under poplar,birch,and their mixed forests,although the soil microbial biomass was lower.The direct contribution of vegetation types to the soil microbial community variation was 12%.If the indirect contribution through soil organic carbon was included,variations in the vegetation type had substantial influences on soil microbial composition and diversity. | WANG Miao QU LaiYe MA KeMing YUAN Xiu | 2013 | Science China(Life Sciences)2013，56，6： | 10 |
| 3 | Contrasting elevational diversity patterns for soil bacteria between two ecosystems divided by the treeline显示文摘Above- and below-ground organisms are closely linked, but how elevational distribution pattern of soil microbes shifting across the treeline still remains unknown. Sampling of 140 plots with transect, we herein investigated soil bacterial distribution pattern from a temperate forest up to a subalpine meadow along an elevational gradient using Illumina sequencing. Our results revealed distinct elevational patterns of bacterial diversity above and below the treeline in responding to changes in soil conditions:a hollow elevational pattern in the forest(correlated with soil temperature, pH, and C:N ratio) and a significantly decreasing pattern in the meadow(correlated with soil pH, and available phosphorus). The bacterial community structure was also distinct between the forest and meadow, relating to soil pH in the forest and soil temperature in the meadow. Soil bacteria did not follow the distribution pattern of herb diversity, but bacterial community structure could be predicted by herb community composition. These results suggest that plant communities have an important influence on soil characteristics, and thus change the elevational distribution of soil bacteria. Our findings are useful for future assessments of climate change impacts on microbial community. | Guixiang Li Guorui Xu Congcong Shen Yong Tang Yuxin Zhang Keming Ma | 2016 | Science China(Life Sciences)2016，59，11： | 9 |
| 4 | Comparison on Soil Carbon Stocks Between Urban and Suburban Topsoil in Beijing, China显示文摘The urban population and urbanized land in China have both increased markedly since the 1980 s. Urban and suburban developments have grown at unprecedented rates with unknown consequences for ecosystem functions. In particular, the effect of rapid urbanization on the storage of soil carbon has not been studied extensively. In this study, we compared the soil carbon stocks of different land use types in Beijing Municipality. We collected 490 top-soil samples(top 20 cm) from urban and suburban sites within the Sixth Ring Road of Beijing, which cover approximately 2400 km2, and the densities of soil organic carbon(SOC), soil inorganic carbon(SIC), and total carbon(TC) were analyzed to determine the spatial distribution of urban and suburban soil carbon characteristics across seven land use types. The results revealed significant differences in soil carbon densities among land use types. Additionally, urban soil had significantly higher SOC and SIC densities than suburban soil did, and suburban shelterbelts and productive plantations had lower SIC densities than the other land use types. The comparison of coefficients of variance(CVs) showed that carbon content of urban topsoil had a lower variability than that of suburban topsoil. Further findings revealed that soil carbon storage increased with built-up age. Urban soil built up for more than 20 years had higher densities of SOC, SIC and TC than both urban soil with less than 10 years and suburban soil. Correlation analyses indicated the existence of a significantly negative correlation between the SOC, SIC, and TC densities of urban soil and the distance to the urban core, and the distance variable alone explained 23.3% of the variation of SIC density and 13.8% of the variation of TC density. These results indicate that SOC and SIC accumulate in the urban topsoil under green space as a result of the conversion of agricultural land to urban land due to the urbanization in Beijing. | LUO Shanghua MAO Qizheng MA Keming | 2014 | Chinese Geographical Science2014，24，5： | 8 |
| 5 | Carbon and nitrogen isotopes analysis and sources of organic matter in surface sediments from the Sanggou Bay and its adjacent areas, China显示文摘Naturally existing stable carbon and nitrogen isotopes are important in the study of sedimentary organic matter sources. To identify the sources of sedimentary organic matter in Sanggou Bay and its adjacent areas, which is characterized by high-density shellfish and seaweed aquaculture, the grain size, organic carbon(OC), total nitrogen(TN), carbon and nitrogen isotopic composition(δ13C and δ15N) of organic matter in the surface sediment were determined. The results showed that, in August, sedimentary OC and TN ranged from 0.17% to 0.76% and 0.04% to 0.14%, respectively. In November, OC and TN ranged from 0.23% to 0.87% and 0.05% to 0.14%, respectively. There was a significant positive correlation between OC and TN(R=0.98, P<0.0001), indicating that OC and TN were homologous. In August, the δ13C and δ15N of organic matter varied from-23.06‰ to-21.59‰ and 5.10‰ to 6.31‰, respectively. In November, δ13C and δ15N ranged from-22.87‰ to-21.34‰ and 5.13‰ to 7.31‰, respectively. This study found that the major sources of sedimentary organic matter were marine shellfish biodeposition, seaweed farming, and soil organic matter. Using a three-end-member mixed model, we estimated that the dominant source of sedimentary organic matter was shellfish biodeposition, with an average contribution rate of 65.53% in August and 43.00% in November. Thus, shellfish farming had a significant influence on the coastal carbon cycle. | XIA Bin CUI Yi CHEN Bijuan CUI Zhengguo QU Keming MA Feifei | 2014 | Acta Oceanologica Sinica2014，33，12： | 7 |
| 6 | Seasonal Dynamics of Nitrogen and Phosphorus in Water and Sediment of A Multi-level Ditch System in Sanjiang Plain,Northeast China显示文摘The multi-level ditch system developed in the Sanjiang Plain,Northeast China has sped up water drainage process hence transferred more pollutants from farmlands into the rivers of this region.Understanding the seasonal dynamics of nitrogen (N) and phosphorus (P) transportation in the ditch system and the role of different ditch size is thus crucial for water pollution control of the rivers in the Sanjiang Plain.In this study,an investigation was conducted in the Nongjiang watershed of the Sanjiang Plain to study the nutrient variation and the correlation between water and sediments in the ditch system in terms of ditch level.Water and sediments samples were collected in each ditch level in growing season at regular intervals (once per month),and TN,NO 3--N,NH 4+-N,TP,and PO 4 3--P were analyzed.The results show that nutrient contents in water were higher in June and July,especially in July,the contents of TN and TP were 3.21mg/L and 0.84mg/L in field ditch,4.04mg/L and 1.06mg/L in lateral ditch,2.46mg/L and 0.70mg/L in branch ditch,1.92mg/L and 0.63mg/L in main ditch,respectively.In August and September,the nutrient contents in the water were relatively lower.The peak value of nutrient in ditch water had been moving from the field ditch to the main ditch over time,showing a remarkable impact of ditch system on river water environment.The nutrient transfer in ditch sediments could only be found in rainfall season.Nutrient contents in ditch sediment had effect on that in ditch water,but nutrients in ditch water and sediments had different origination.Ditch management in terms of the key fac-tors is hence very important for protecting river water environment. | GUO Le MA Keming | 2011 | Chinese Geographical Science2011，21，4： | 5 |
| 7 | Discovery and its geological significance of the mantle- derived helium in the inclusions of the Ordovician oil-bearing reservoir rocks in the Huanghua depression,China显示文摘The values of the helium isotopes in the inclusions of the Ordovician reservoir rocks in the Kongxi buried hill belt in the Huanghua depression were first measured and the source of helium and its geological significance were investigated in comparison with those of the helium isotopes in the conclusions in the Ordovician rocks in the Ordos basin and the Tarim basin. The input of the mantle-derived helium into the inclusions in the carbonate reservoir rocks was found from the Konggu 3 well, the Konggu 4 well, and the Konggu 7 well in the Kongxi buried hill belt. The 3He/4He and R/Ra in the conclusions in the Ordovician oil-bearing reservoir rocks in the Konggu 7 well average 2.54×10-6(3) (sample quantity, the same below) and 1.82(3), respectively. The percent of the mantle-derived helium in the inclusions of the reservoir rocks in the Konggu 7 well reaches up to an average of 23.0%(3). The age of the contribution of the mantle-derived helium to the inclusions in the Kongxi buried hill belt is in the Late Triassic or the Early Tertiary. The finding of the mantle-derived helium shows that the interaction of the deep crust with mantle and the activity of deep faults occurred, the terrestrial heat flow value was high, and mantle-derived inorganic gas pools might be formed in the Kongxi buried hill belt. The finding of the mantle-derived helium in the inclusions of oil-bearing reservoir rocks also provides a new way for researching the activity of mantle-derived matter and its associated geological problems. | ZHANG Xiaobao XU Yongchang SUN Mingliang CHENG Keming LIU Wenhui LI Xiufen MA Liyuan | 2004 | Science China Earth Sciences2004，47，1： | 4 |
| 8 | Quantifying the characteristics of particulate matters captured by urban plants using an automatic approach显示文摘It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer studies, however, have examined the particle density, and the size and shape characteristics of particles, which may have important implications for evaluating the particle capture efficiency of plants, and identifying the particle sources. In addition, the role of different vegetation types is as yet unclear. Here, we chose three species of different vegetation types, and firstly applied an object-based classification approach to automatically identify the particles from scanning electron microscope(SEM)micrographs. We then quantified the particle capture efficiency, and the major sources of particles were identified. We found(1) Rosa xanthina Lindl(shrub species) had greater retention efficiency than Broussonetia papyrifera(broadleaf species) and Pinus bungeana Zucc.(coniferous species), in terms of particle number and particle area cover.(2) 97.9% of the identified particles had diameter ≤10 μm, and 67.1% of them had diameter ≤2.5 μm. 89.8% of the particles had smooth boundaries, with 23.4% of them being nearly spherical.(3) 32.4%–74.1% of the particles were generated from bare soil and construction activities, and 15.5%–23.0% were mainly from vehicle exhaust and cooking fumes. | Jingli Yan Lin Lin Weiqi Zhou Lijian Han Keming Ma | 2016 | Journal of Environmental Sciences2016，28，1： | 3 |
| 9 | Effects of plant coverage on shrub fertile islands in the Upper Minjiang River Valley显示文摘The patchy distribution of vegetation in dry land results in well-documented 'fertile islands'. However, the response of shrub fertile islands to plant recovery and the underlying mechanisms, such as the linkage plant and soil properties, remain unknown.We sampled soils from areas with three different plant coverages(25%, 45%, and 75%) and three of their adjacent inter-plants to investigate soil physicochemical and microbial properties in the upper Minjiang River arid valley. The results showed that these factors were influenced by the persistence of plants that contrasted with the inter-plant interspaces. We found fertile islands in under-plant soil that were enhanced with increasing plant coverage, from 25% to 45% and 75%; however, there were no significant differences between 45% and 75% plant coverage apart from the soil clay content and the fungi to bacteria ratio. The soil microbial communities in under-plant soil were strongly influenced by the total soil carbon(TC), soil organic carbon(SOC),and available nitrogen(AN), whereas the microbial communities in inter-plant soil were primarily constrained by the AN and available phosphorous(AP). Moreover, the inter-plant soil properties, including gravimetric soil water content, pH, electrical conductivity(EC), and soil C:N ratio, were also strongly influenced by adjacent vegetation, which suggested that fertile islands may be beneficial for plant recovery in this region. | Laiye Qu Zhongbin Wang Yuanyuan Huang Yuxin Zhang Chengjun Song Keming Ma | 2018 | Science China(Life Sciences)2018，61，3： | 3 |
| 10 | Spatial heterogeneity of urban soils:the case of the Beijing metropolitan region,China显示文摘Introduction:Urban soils are large pools of carbon,nitrogen,and other elements,supporting plant growth,sustaining biogeochemical cycles,and serving as the foundation for maintaining ecosystem function and services of urban green spaces(UGS).Quantifying urban soil properties is essential for assessing urban ecosystem services and detecting pollution.Characterizing spatial heterogeneity of urban soil properties,which may change with land use or urbanization,is crucial for understanding urban ecosystem functions.Methods:We collected 466 soil composite samples across the Beijing metropolitan region and then analyzed the heterogeneity of soil properties in UGS of Beijing metropolitan region by ANOVA along the urbanization gradient spanning different land uses.Results:Our results show that soil properties vary considerably among land-use types and along the urban-rural gradient.Soil moisture content,soil organic carbon(SOC),available phosphorus,available potassium,total nitrogen(TN),the ratio of SOC:TN(C/N),Pb,and Cu increased notably from suburbs to the urban core,while soil pH,bulk density,TN,Cr,Ni,and Mn were not significantly different across urbanization levels.Most soil properties,except soil TN,Cu,Cr,Ni,exhibited significant differences between different land uses.The highest levels of soil nutrients and heavy metals were found in roadsides and residential areas among all the land uses.Conclusions:The spatial heterogeneity of urban soils in the Beijing metropolitan region is mainly attributable to the different land uses.Soil nutrient content has increased in UGS due to fertilization and pollution.Contamination of urban soils by heavy metals is due largely to traffic emissions and pollution by industrial and household wastes.Although human activities tend to augment urban soil nutrient pools to maximize certain ecosystem services,they may inadvertently compromise these and other services by increasing pollution.Knowledge of urban soil spatial heterogeneity in UGS is indispensable for improving urban ecosystem management. | Qizheng Mao Ganlin Huang Alexander Buyantuev Jianguo Wu Shanghua Luo Keming Ma | 2014 | Ecological Processes2014，3，1： | 2 |
| 11 | Partitioning the effects of environmental and spatial heterogeneity on distribution of plant diversity in the Yellow River Estuary显示文摘For successful conservation and restoration of biodiversity,it is important to understand how diversity is regulated.In the ecological research community,a current topic of interest is how much of the variation in plant species richness and composition is explained by environmental variation(niche-based model),relative to spatial processes(neutral theory).The Yellow River Estuary(YRE) is a newly formed and fragile wetland ecosystem influenced by both the Yellow River and Bohai Bay.Here,we applied variance partitioning techniques to assess the relative effects of spatial and environmental variables on species richness and composition in the YRE.We also conducted a species indicator analysis to identify characteristic species for three subestuaries within the YRE.Partial redundancy analysis showed that the variations in species richness and composition were explained by both environmental and spatial factors.The majority of explained variation in species richness and composition was attributable to local environmental factors.Among the environmental variables,soil salinity made the greatest contribution to species abundance and composition.Soil salinity was the most important factor in the Diaokou subestuary,while soil moisture was the most important factor influencing species richness in the Qingshui and Chahe subestuaries.The combined effects of soil salinity and moisture determined species richness and composition in the wetlands.These results increase our understanding of the organization and assembly of estuarine plant communities. | YUAN Xiu MA KeMing WANG De | 2012 | Science China(Life Sciences)2012，55，6： | 2 |
| 12 | A segmentation method for processing greenhouse vegetable foliar disease symptom images显示文摘Uneven illumination and clutter background were the most challenging problems to segmentation of disease symptom images.In order to achieve robust segmentation,a method for processing greenhouse vegetable foliar disease symptom images was proposed in this paper.The segmentation method was based on a decision tree which was constructed by a two-step coarse-to-fine procedure.Firstly,a coarse decision tree was built by the CART(Classification and Regression Tree)algorithm with a feature subset.The feature subset consisted of color features that was selected by Pearson’s Rank correlations.Then,the coarse decision tree was optimized by pruning.Using the optimized decision tree,segmentation of disease symptom images was achieved by conducting pixel-wise classification.In order to evaluate the robustness and accuracy of the proposed method,an experiment was performed using greenhouse cucumber downy mildew images.Results showed that the proposed method achieved an overall accuracy of 90.67%,indicating that the method was able to obtain robust segmentation of disease symptom images. | Juncheng Ma Keming Du Feixiang Zheng Lingxian Zhang Zhongfu Sun | 2019 | Information Processing in Agriculture2019，6，2： | 2 |
| 13 | Testing a Dynamic Complex Hypothesis in the Analysis of Land Use Impact on Lake Water Quality显示文摘 | QingHai Guo KeMing Ma Liu Yang Kate He | 2010 | Water Resources Management2010，，7： | 1 |
| 14 | The rela- tionship between land use and soil conditions in the hilly area of Loess Plateau in Northern Shaanxi, China显示文摘 | Fu Bojie Chen Liding Ma Keming | 2000 | Catena2000，39，1： | 1 |
| 15 | SCN1A, SCN1B, and GABRG2 gene mutation analysis in Chinese families with generalized epilepsy with febrile seizures plus显示文摘 | Huihui Sun Yuehua Zhang Jianmin Liang Xiaoyan Liu Xiuwei Ma Husheng Wu Keming Xu Jiong Qin Yu Qi Xiru Wu | 2008 | Journal of Human Genetics2008，，8： | 1 |
| 16 | The relationships between land use and soil conditions in the hilly area of the loess plateau in northern Shaanxi, China显示文摘 | Bojie Fu Liding Chen Keming Ma Huafeng Zhou Jun Wang | 2000 | Catena2000，，1： | 1 |
| 17 | The Relationships Between Land-use and Soil Conditions in the Hilly Area of the Loess Plateau in Northern Shaanxi, China 显示文摘 | Fu hoie Chen Liding Ma Keming | 2000 | Catena2000，395，： | 1 |
| 18 | A comparative study of the impact of species composition on a freshwater phytoplankton community using two contrasting biotic indices显示文摘 | Qinghai Guo Keming Ma Liu Yang Qinghua Cai Kate He | 2009 | Ecological Indicators2009，，2： | 1 |
| 19 | Beijing Urbanization in the Past 18 years显示文摘 | MA Keming ZHOU Liang NIU Shukui | 2005 | Journal of International Development and Cooperation2005，11，2： | 1 |
| 20 | Expression of protein kinase C isoforms in cultured human retinal pigment epithe- lial cells显示文摘 | Keming Yu Ping Ma Jian Ge | 2007 | Graefes Arch Clin Exp Ophthalmol2007，245，7： | 1 |
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