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Comparisons of carbon storages in Cunninghamia lanceolata and Michelia macclurei plantations during a 22-year period in southern China

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Journal of Environmental Sciences 2009年第6期21卷 801-805页

作者： NIU Dong WANG Silong OUYANG Zhiyun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Huitong experimental station of Forest Ecology Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

Tree species composition was important for carbon storage within the same climate *** quantify the dynamics of ecosystem carbon allocation as affected by different tree species,we measured the above-and below-ground biomass accumulation in 22 years,as well as the tissue carbon concentrations of trees in Cunninghamia lanceolata plantation and Michelia macclurei *** indicated that *** plantation significantly stored more carbon（174.8 tons/hm2） than *** plantation（154.3 tons/hm2）.Most of the carbon was found in the soil pool（57.1% in *** plantation,55.2% in *** plantation）.Tree and soil component of *** plantation possessed significantly higher carbon storage than that of *** plantation（p 〈 0.05）.No significant difference was found in the carbon storage of understory and forest *** results suggest that the broadleaved species（***） possesses greater carbon sequestration potential than the coniferous species（***） in southern China.

关键词： Cunninghamia lanceolata plantation Michelia macclurei plantation carbon storage carbon allocation patterns

Summer atmospheric boundary layer structure in the hinterland of Taklimakan Desert, China

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Journal of Arid Land 2016年第6期8卷 846-860页

作者： WANG Minzhong WEI Wenshou HE Qing YANG Yuhui FAN Lei ZHANG Jiantao Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Taklimakan Desert Atmospheric Environment Observation experimental station Tazhong 841000 China School of Geographic Science and Tourism Xinjiang Normal University Urumqi 830054 China

Understanding the characteristics of the structure of desert atmospheric boundary layer and its land surface process is of great importance to the simulations of regional weather and climate. To investigate the atmospheric boundary layer structure and its forming mechanism of Taklimakan Desert, and to improve the accuracy and precision of regional weather and climate simulations, we carried out a GPS radiosonde observation experiment in the hinterland of Taklimakan Desert from 25 June to 3 July, 2015. Utilizing the densely observed sounding data, we analyzed the vertical structures of daytime convective boundary layer and nighttime stable boundary layer in summer over this region, and also discussed the impacts of sand-dust and precipitation events on the desert atmospheric boundary layer structure. In summer, the convective boundary layer in the hinterland of Taklimakan Desert developed profoundly and its maximum height could achieve 4,000 m; the stable boundary layer at nighttime was about 400-800-m thick and the residual mixing layer above it could achieve a thickness over 3,000 m. Sand-dust weather would damage the structures of nighttime stable boundary layer and daytime convective boundary layer, and the dust particle swarm can weak the solar radiation absorbed by the ground surface and further restrain the strong development of convective boundary layer in the daytime. Severe convective precipitation process can change the heat from the ground surface to the atmosphere in a very short time, and similarly can damage the structure of desert atmospheric boundary layer remarkably. Moreover, the height of atmospheric boundary layer was very low when raining. Our study verified the phenomenon that the atmospheric boundary layer with supernormal thickness exists over Taklimakan Desert in summer, which could provide a reference and scientific bases for the regional numerical models to better represent the desert atmospheric boundary layer structure.

关键词： convective boundary layer effects of sand-dust and precipitation GPS radiosonde observation the hinterland of Taklimakan Desert

Marginal land bioethanol production of sweet sorghum based on limited water resources in Northwest China

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 132-138页

作者： Xinjie Shi Taisheng Du Pingguo Dong Tiemin Hu Center for Agricultural Water Research in China China Agricultural UniversityBeijing 100083China Wuwei experimental station for Efficient Water Use in Agriculture Ministry of Agriculture and Rural AffairsWuwei 733000GansuChina

Sweet sorghum is considered a leading non-grain candidate for bioethanol production due to its low input requirement,good tolerance,high biomass potential,and high sugar ***,insufficient studies have been conducted on the spatial distribution of sweet sorghum-based bioethanol production potential considering the water resources *** presented a multi-factor analysis method not only considering terrain,meteorology,soil,and crop natural growth habits but also considering the local water resource to explore the available marginal land suitable for sweet sorghum cultivation and assess the bioethanol production potential in Northwest *** results showed that 4.63×10^(7)hm^(2)available marginal land was suitable for sweet sorghum *** the constraint of local water resources,2.76×10^(6)hm^(2)available marginal land was suitable for sweet sorghum planting,accounting for 4.7%of the total available marginal *** 1.23×10^(10)L bioethanol could be produced on ***,for these districts under low water stress levels,9.79×10^(5)hm^(2)available marginal land in Gannan Tibet AP and Longnan of Gansu and Hulun Buir of Inner Mongolia was considered a priority to develop sweet sorghum-based bioethanol,and 5.56×10^(9)L bioethanol could be produced in these districts,which can satisfy the 1.54%biofuel goal for 2050 of China.

关键词： bioethanol potential marginal land sweet sorghum regional water stress levels water resources limitation

Aerosol Hygroscopicity during the Haze Red-Alert Period in December 2016 at a Rural Site of the North China Plain

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Journal of Meteorological Research 2018年第1期32卷 38-48页

作者： Xuefei QI Junying SUN Lu ZHANG Xiaojing SHEN Xiaoye ZHANG Yangmei ZHANG Yaqiang WANG Haochi CHE Zhouxiang ZHANG Junting ZHONG Kaiyan TAN Huarong ZHAO Sanxue REN State Key Laboratory of Severe Weather、Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological Sciences Beijing 100081 Integrated Ecological-Meteorological Observation and experimental station Chinese Academy of Meteorological Sciences Beijing 100081

A humidification system was deployed to measure aerosol hygroscopicity at a rural site of the North China Plain during the haze red-alert period 17–22 December 2016. The aerosol scattering coefficients under dry [relative humidity（RH）〈 30%] and wet（RH in the range of 40%–85%） conditions were simultaneously measured at wavelengths of450, 550, and 700 nm. It is found that the aerosol scattering coefficient and backscattering coefficient increased by only 29% and 10%, respectively when RH went up from 40% to 80%, while the hemispheric backscatter fraction went down by 14%, implying that the aerosol hygroscopicity represented by the aerosol scattering enhancement factor f（RH） is relatively low and RH exerted little effects on the aerosol light scattering in this case. The scattering enhancement factors do not show significant differences at the three wavelengths, only with an approximate 2% variation, suggesting that the aerosol hygroscopicity is independent of the wavelength. Aerosol hygroscopicity is highly dependent on the aerosol chemical composition. When there is a large mass fraction of inorganics and a small mass fraction of organic matter, f（RH） reaches a high value. The fraction of NO3^- was strongly correlated with the aerosol scattering coefficient at RH = 80%, which suggests that NO3^- played an important role in aerosol hygroscopic growth during the heavy pollution period.

关键词： aerosol hygroscopicity scattering enhancement factor chemical composition

Adaptation to a Warming-Drying Trend Through Cropping System Adjustment over Three Decades:A Case Study in the Northern Agro-Pastural Ecotone of China

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Journal of Meteorological Research 2015年第3期29卷 496-514页

作者：张婧婷安萍莉潘志华郝宝针王立为董智强潘学标薛青武 College of Resources and Environmental Science China Agricultural University Key Ecology and Environment experimental station of Ministry of Agriculture for Field Scientific Observation in Hohhot Crop Physiology Texas A&M AgriLife Research-Amarillo6500 Amarillo Blvd West

Long-term field monitoring data and historical crop data are useful to assess the impacts of climate change and to manage cropping systems. The objectives of this study are to understand the cropping system response to a warming-drying trend in the northern agro-pastural ecotone （NAE） of China and to document how farmers can adapt to the warming-drying trend by changing cropping system structure and adjusting planting date. The results indicate that a significant warming-drying trend existed in the NAE from 1980 to 2009, and this trend significantly decreased crop （spring wheat, naked oat, and potato） yields. Furthermore, the yield decreased by 16.2%-28.4% with a 1℃ increase in maximum temperature and decreased by 6.6%-11.8% with a 10% decrease in precipitation. Considering food security, water use efficiency, and water ecological adaptability in the semi-arid NAE, cropping system structure adjustment （e.g., a shift from wheat to potato as the predominant crop） and planting date adaptation （e.g., a delay in crop planting date） can offset the impact of the warming-drying trend in the NAE. Based on the successful offsetting of the impact of the warming-drying trend in the NAE, we conclude that farmers can reduce the negative effects of climate change and minimize the risk of crop failure by adapting their cropping system structure at the farming level.

关键词： warming-drying trend cropping system structure adjustment planting date change water use efficiency water ecological adaptability northern agro-pastural ecotone of China

Temporal and spatial variations in the distribution of macroalgal communities along the Yantai coast, China

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Chinese Journal of Oceanology and Limnology 2014年第3期32卷 595-607页

作者：韩秋影刘东艳 Key Laboratory of Coastal Zone Environmental Processes CAS Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes CAS experimental station of Integrated Coastal Environment in Muping Yantai Institute of Coastal Zone Research Chinese Academy of Sciences

To explore the impact of environmental variables on macroalgal communities, their temporal and spatial distributions were examined along the Yantai coast, China between April 2010 and March 2011. Macroalgae sampling was conducted monthly at four sites along the coast: Jiahe River estuary, Zhifu Island, Fisherman's Wharf, and Yangma Island. The species composition and abundance, and their relationship with environmental variables were assessed. Along the Yantai coast, 35 macroalgae species were identifi ed, including 24 Rhodophyta spp., 7 Chlorophyta, and 4 Phaeophyta spp. Highest species numbers were recorded in the summer at all sampling sites, except in the Jiahe River estuary. Macroalgae biomass was the greatest in the summer. Year-round, the highest species number and dry biomass recorded at Fisherman's Wharf and Yangma Island was attributed to the substrate type. In summer, Ulva pertusa Kjellman was the dominant species identifi ed along the Yantai coast, which indicates a risk of macroalgae blooms. Our results show that seawater temperature and nutrients appear to signifi cantly affect the temporal and spatial patterns of macroalgal abundance along the Yantai coast. The effects of environmental variables on the macroalgae on the Yantai coast need further study.

关键词： macroalgae temporal spatial intertidal nutrient Yantai coast China

Genetic diversity of rhizobial populations recovered from three Lotus species cultivated in the infra-arid Tunisian soils

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Progress in Natural Science:Materials International 2009年第9期19卷 1079-1087页

作者： Mokhtar Rejili Maria Josè Lorite Mosbah Mahdhi Juan Sanjuan Pinill Ali Ferchichi Mohamed Mars Arid & Oases Cropping Laboratory Arid Area Institute (IRA) Laboratory of Plant Biotechnology Applied to Crop Improvement Faculty of Sciences of Gabès Soil Microbiology & Symbiotic Systems Department Experimental Station of Zaidìn

Eighty-three bacterial strains isolated from root nodules of Lotus creticus, L. pusillus, and L. arabicus grown in infra-arid Tunisian soils were characterized using a polyphasic approach including phenotypic analysis, rep-PCR and PCR-RFLP analyses of the 16S rRNA gene. Phenotypically, all isolates are fast growers the majority of which grow at a pH of between 5.5 and 9. Most of the tested isolates tolerate NaCl concentrations from 1.39% to 3.48%. By rep-PCR fingerprinting, the genomic similarity varied from 30% to 98%. All tested isolates were clustered into 32 rep-PCR clusters at the similarity level of 80%. The genomic divergence of strains revealed by rep/PCR analysis appeared to be very important since a molecular polymorphism delimiting symbionts for each species of Lotus was identified. With the high-resolution of rep-PCR profiles of the isolates obtained using Pearson’s/UPGMA analysis, the isolates were resolved into 60 different profiling groups to undergo 16S ARDRA analyses. The analysis of all restriction fragments from each strain based on the UPGMA algorithm from the combined patterns showed that Lotus isolates are very diverse and that they were affiliated to Sinorhizobium, Rhizobium, and Mesorhizobium genera.

关键词： Lotus sp. rep-PCR fingerprinting PCR-RFLP 16S rRNA Rhizobia Arid habitat

THE RELATIONSHIP BETWEEN HEIGHT AND TEMPERATURE OF ICE CRYSTALLIZATION IN CUMULUS CLOUDS IN JIUJIANG AREA

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Chinese Science Bulletin 1980年第9期25卷 760-762页

作者：江祖凡李太丰 Lushan experimental station of Clouds and Fogs Central Bureau of Meteorology

In the southern part of China the most important precipitation comes from the cumulonimbus. So many researchers of clouds and precipitation devote much of their attention to the study of ice crystallization in the cum... 详细信息

关键词： devote comes maybe Florida latter fifth 巴口厂卫 elevation analysed

Development and application of marker-assisted reverse breeding using hybrid maize germplasm

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Journal of Integrative Agriculture 2015年第12期14卷 2538-2546页

作者： GUAN Yi-Xin WANG Bao-hua FENG Yan LI Ping Scientific Observing and experimental station of Maize in Plain Area of Southern Region Ministry of AgricultureSchool of Life Sciences Nantong University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Nantong Xinhe Bio-Technology Co. Ltd.

Humankind has been through different periods of agricultural improvement aiming at enhancing our food supply and the performance of food crops. In recent years, whole genome sequencing and deep understanding of genetic and epigenetic mechanisms have facilitated new plant breeding approaches to meet the challenge of growing population, dwindling resources, and changing climate. Here we proposed a simple and fast molecular breeding method, marker-assisted reverse breeding（MARB）, which will revert any maize hybrid into inbred lines with any level of required similarity to its original parent lines. Since all the pericarp DNA of a hybrid is from the maternal parent, whereas one half of the embryo DNA is from the maternal parent and the other half from the paternal parent, so we firstly extract DNA from seed embryo and pericarp of a selected elite hybrid separately and then we derived the genotypes of the two parents with high-density single nucleotide polymorphism（SNP） chips. The following marker-assisted selection was performed based on an Illumina low-density SNP chip designed with 192 SNPs polymorphic between the two parental genotypes, which were uniformly distributed on 10 maize chromosomes. This method has the advantages of fast speed, fixed heterotic mode, and quick recovery of beneficial parental genotypes compared to traditional pedigree breeding using elite hybrids. Meanwhile, MARB has the advantage of not requiring sophisticated transformation and double haploid（DH） technologies over RNA interference（RNAi）-mediated reverse breeding. In addition, MARB can also be used with feed corn harvested from big farms, which is often similar to F_2 populations, and the relevant transgenes in the population can be eliminated by marker-assisted selection. As a result, the whole global commercial maize hybrids can be utilized as germplasm for breeding with MARB technology. Starting with an F_2 population derived from an elite hybrid, our experiment indicates that with three

关键词： maize hybrid marker-assisted reverse breeding SNP