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Chinese Geographical Science 2013年第1期23卷 26-34页

作者： LIU Yong WANG Cheng YUE Wenze HU Yanyan College of Resources and Environment Southwest University institute of Land Science and Property Management Zhejiang University Chongqing institute of landscape Gardening

Rapid urbanization results in the conversion of natural soil to urban soil,and consequently,the storage and density of the soil carbon pools *** Chongqing Municipality of China as a study case,this investigation attempts to better understand soil carbon pools in hilly ***,the vegetated areas in the study area were derived from QuickBird ***,topsoil data from 220 soil samples(0-20 cm) in the vegetated areas were collected and their soil organic carbon(SOC) densities were *** the Kriging interpolation method,the spatial pattern of SOC was *** results show that the SOC density exhibited high spatial variability in the urban topsoil of ***,the SOC density in topsoil decreased according to slope in the order 2°-6° < 25°-90° < 0°-2° < 6°-15° < 15°-25°.Second,the newly developed areas during 2001-2010 had a lower SOC density than the areas built before ***,urban parks and gardens had a higher SOC density in topsoil,residential green land followed,and scattered street green land ranked *** hilly cities,the variability of terrain affects the distribution of *** Kriging results indicate that Kriging method combining slope with SOC density produced a high level of *** Kriging results show that the SOC density to the north of the Jialing River was higher than the *** vegetated areas were estimated to amount to 73.5 km2 across the study area with an SOC storage of 0.192 Tg and an average density of 2.61 kg/m2.

关键词： soil organic carbon (SOC) topsoil hilly city Kriging interpolation

Soil Organic Carbon Stocks of Citrus Orchards in Yongchun County Fujian Province China

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Pedosphere 2017年第5期27卷 985-990页

作者： WANG Yixiang WENG Boqi TIAN Na ZHONG Zhenmei WANG Mingkuang institute of Agricultural ecology Fujian Academy of Agricultural Sciences

Studies related to the quantitation and distribution of soil organic carbon （C） under different land use types can help to fill the knowledge gaps regarding estimation of the amount of C stored in soils at a global scale. Orchards are an important land use type in southern China; the total area （1.15 x 107 ha） of orchards in China comprises approximately 20.5% of the area of all orchards worldwide. We assessed soil organic C stocks （SOCS） in citrus orchards in Yongchun County （consisting of 22 towns）, Fujian Province, China in 1982 and 2010. The southeastern part of the county, an area featuring extensive citrus farming with a gently sloping landscape and low rates of water erosion, had the highest SOCS. In contrast, the lowest SCOS was observed in the northern part of the county, where steep hills with severe erosion problems are common and citrus orchards are sparsely distributed. From 1982 to 2010, the mean SOCS in citrus orchards increased from 22.1 to 41.7 Mg ha-1 which indicated that current management practices such as fertilization, irrigation, and cultivation enhanced soil C stocks. Further in-depth studies on the effects of these practices on C sequestration would be worthwhile and surveys of SOCS throughout Fujian Province are needed, to support efforts to mitigate global C emission.

关键词： carbon emission carbon pool carbon sequestration kriging land use type management practices

Effect of No Tillage and Conventional Tillage on Wheat Grain Yield Variability: A Review

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Journal of Environmental & Earth Sciences 2024年第1期6卷 57-70页

作者： Kenza Kadiri Hassani Moussadek Rachid Baghdad Bouamar Zouahri Abdelmjid Dakak Houria Maher Hassnae Bouabdli Abdelhak Laboratory of Geosciences Department of GeologyFaculty of SciencesIbn Tofail UniversityKenitra B.P.242Morocco International Center for Agricultural Research in the Dry Areas(ICARDA) Rabat P.O.Box 1014Morocco Research Unit on Environment and Conservation of Natural Resources Regional Center of RabatNational Institute of Agricultural ResearchRabat P.O.Box 6356Morocco Georesources Environmentalist Consultant/Expert Associate Professor at Casablanca School of Architecture and Landscape-Honoris United UniversitiesCasablancaB.P.20100Morocco Laboratory of Materials Nanotechnology and EnvironmentDepartment of ChemistryFaculty of SciencesMohammed V UniversityRabat B.P.703Morocco

Conservation Agriculture(CA)covers more than 205 million hectares in the *** made it possible to face and mitigate the challenges of climate change,reducing soil erosion and providing multiple ecosystem *** first elementary factor influenced is the yield *** has a direct effect on farmers’choices for sustainable *** present article records a review focused on wheat yield average positive change compared between conventional tillage(CT)and no tillage(NT)*** international database collected showed that NT is adaptable *** results of wheat yield differentiation showed the influence of crop rotation depending on stations located in different climatic *** more than 40 years of research,specialists have succeeded in demonstrating the importance of crop productivity like *** whole integrates also experimentations where the initiation starts more than ten years.

关键词： Climate change No tillage Crop rotation Wheat Yield

GIS-based analysis of forest degradations in Baihe Forestry Bureau,northeast China

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Science China(Technological Sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei institute of Applied ecology, Chinese Academy of Sciences, Shenyang 110016, China Graduate University of Chinese Academy of Sciences, Beijing 100101, China Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Department of City Development, Jinan University, Jinan 250002, China Academy of Forest Inventory and Planning, State Forestry Administration, Beijing 100714, China institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China

Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

Simulating　sensitivities　of　Changbai　Mountain　forests　to　potential　climate　change

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Journal of Environmental Sciences 1996年第3期8卷 354-366页

作者： Yan Xiaodong Zhao Shidong (institute of Applied ecology. Chinese Academy of Sciences,Shenyang 110015, China) institute of Applied ecology Chinese Academy of Sciences Shenyang 110015 China

Changbai Mt. forest in the northeastern China is both a very important timber resource of China and one of the most typical and less disturbed temperate mixed evergreen coniferous-deciduous forest in the *** this paper, NEWCOP. a gap class model of forest growth and succession was proposed to simulate the sensitivity of the forest in Changbai Mountain to elevate CO_2. warmer temperature and precipitation change. NEWCOP was tested on long term simulation behaviors and short term fitting ability to field data. About the response of forests of Changbai Mountain to possible climate change, NEWCOP suggested that forest landscape go up within long term and forest biomass comes down within short term because of dieback of forest trees.

关键词： gap model climate change forests China.

Soil Moisture Rather than Soil Nutrient Regulates the Belowground Bud Bank of Rhizomatous Species Psammochloa villosa in Arid Sand Dunes

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Phyton-International Journal of Experimental Botany 2023年第5期92卷 1301-1309页

作者： Yawei Dong Ziyue Guo Qun Ma Zhiming Xin Jin Tao Jiatai Tian Jinlei Zhu Zhiming Zhang Jianqiang Qian College of Forestry Henan Agricultural UniversityZhengzhou450002China institute of Applied ecology Chinese Academy of SciencesShenyang110164China Experimental Center of Desert Forestry Chinese Academy of ForestryInner Mongolia Dengkou Desert Ecosystem National Observation Research StationDengkouBayan Nur015200China institute of landscape and Plant ecology University of HohenheimStuttgart70599Germany

In arid and semi-arid sand dune ecosystems,belowground bud bank plays an important role in population regeneration and vegetation ***,the responses of belowground bud bank size and composition to sand burial and its induced changes in soil environmental factors have been rarely *** arid sand dunes of Northwestern China,we investigated belowground bud bank size and composition of the typical rhizomatous psammophyte Psammochloa villosa as well as three key soil environmental factors(soil moisture,total carbon and total nitrogen)under different depths of sand *** buds and rhizome buds increased significantly with increasing burial depth,whereas tiller buds first increased and then decreased,with a peak value at the depth of 20-30 *** moisture increased significantly with sand burial depth,and was positively correlated with the number of all buds and rhizome *** total carbon concentration first increased and then decreased with sand burial depth,and total nitrogen concentration was significantly lower under deep sand burial than those at shallow depths,and only the number of tiller buds was positively correlated with soil total nitrogen *** results indicate that soil moisture rather than soil nutrient might regulate the belowground bud bank of ***,and that clonal psammophytes could regulate their belowground bud bank in response to sand burial and the most important environmental stress(i.e.,soil moisture).These responses,as the key adaptive strategy,may ensure clonal plant population regeneration and vegetation restoration in arid sand dunes.

关键词： Adaptive strategy clonal plant population regeneration psammophyte vegetation restoration

Characterization and function of Tomato yellow leaf curl virus-derived small RNAs generated in tolerant and susceptible tomato varieties

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Journal of Integrative Agriculture 2016年第8期15卷 1785-1797页

作者： BAI Miao YANG Guo-shun CHEN Wen-ting LIN Run-mao LING Jian MAO Zhen-chuan XIE Bing-yan College of Horticulture and landscape Hunan Agricultural University institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences

supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China （20134320120013）;the Natural Science Foundation of Hunan Province, China （14JJ3095）

关键词： Tomato yellow leaf curl virus virus-induced RNA silencing virus-derived small RNA degradome

Recent landscape and trends for industry-sponsored pediatric clinical trials in China from 2013 to 2022

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Pediatric Investigation 2024年第1期8卷 12-20页

作者： Chang Liu Yi Liu Ling Ou Yuenan Qi Jianmin Zhang Drug Clinical Trial Institution Children’s HospitalCapital Institute of PediatricsBeijingChina

Importance:Pediatric medication is a challenging issue *** trials of medications for children and implementing measures to encourage innovation for addressing unmet medical and health needs are ***:To explore the recent landscape of pediatric clinical trials of new investigational drugs conducted by pharmaceutical enterprises in China from 2013 to 2022 to provide insight into pediatric drug development in the pharmaceutical industry and regulatory policy ***:We performed a cross-sectional observational investigation of pediatric clinical trials registered from January 1,2013,to December 31,2022,on the Registration and Information Disclosure Platform for Drug Clinical Trials,the official registration platform established in 2013 for trials of new investigational drugs initiated by biopharmaceutical *** that included pediatric participants(under 18 years old)were retrieved,and their relevant characteristics were extracted and ***:In total,895 pediatric clinical trials were collected,accounting for 5.1%of the total registered clinical trials initiated prior to January 1,*** overall average annual growth rate for the number of pediatric clinical trials was 12%(P<0.001).Phase III trials accounted for the highest proportion(49.1%,439).Of the 895 trials included,736(82.2%)were domestic trials,and 159(17.8%)were international multicenter *** terms of tested drugs,investigations of biological products accounted for the largest proportion of trials(67.4%,603).Among pediatric clinical trials,studies of vaccines accounted for the largest proportion of trials(41.0%,367),followed by trials for rare diseases(17.2%,154).Furthermore,geographical distribution analysis revealed that the largest and smallest numbers of trials were conducted in North China(35.7%,320)and Northeast China(0.8%,7),***:The growth trends for industry-sponsored clinical trials involving children illust

关键词： Geographic distribution Pediatric clinical trials Pediatric medication Rare disease

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A novel strategy to enhance resistance to Cucumber mosaic virus in tomato by grafting to transgenic rootstocks

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Journal of Integrative Agriculture 2016年第9期15卷 2040-2048页

作者： BAI Miao CHEN Wen-ting XIE Bing-yan YANG Guo-shun College of Horticulture and landscape Hunan Agricultural University institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences

Cucumber mosaic virus（CMV） can infect a wide range of host species. For the lacking of CMV resistant varieties of tomato, RNA interference（RNAi） can be used as a fast and effective method for the generation of transgenic resistant varieties. In this current study, five intron-spliced hairpin RNA（ihp RNA） plant expression vectors aimed at five genes of CMV have been constructed. Transgenic tomatoes were obtained by Agrobacterium tumefaciens-mediated transformation with expression vectors. Highly resistant generations of transgenic plants were employed as rootstocks and grafted onto non-transgenic tomatoes that resulted in the successful transfer of resistance to the scions. Using a novel method of plant cuttings for rootstock propagation, we obtained large quantities of disease-resistant material. Further, this method produces scions that can remain undetectable for transgenic resistance marker genes that may provide novel approaches to evade collective concerns about genetically-modified organism（GMO） biosafety.

关键词： Cucumber mosaic virus(CMV) graft RNA silencing Solanum lycopersicum virus resistance

A theory to link relationships of stand volume,density,mean diameter and height in forestry data

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Journal of Forestry Research 2021年第1期32卷 15-20页

作者： Vladimir L.Gavrikov Chair of ecology and Environmental Studies Institute Ecology and GeographySiberian Federal University79 pr.SvobodnyiKrasnoyarskRussian Federation 660041

In this study,a geometric model of a growing forest stand has been *** basic relationships considered link stand volume and stand density,diameter at breast height(DBH),mean DBH and mean *** model provides simple formulas connecting the exponents of all the *** of the formulas to real forestry data provided a high level of predictions of an exponent from two others measured through regressions from empirical *** Pinus sylvestris *** were of a static nature,a collection of individual stands,while the Pseudotsuga menziesii(Mirb.)Franco data were dynamic,representing forest stand development over *** ability of the model to predict exponents in the empirical data implies,on the one hand,a substantial level of similarity between the model and the forestry ***,on the other hand,the model gives an example in which parameters of one relationship may be linked to parameters of *** this kind of‘relationship between relationships’may be observed in forest stands undergoing active growth and competition-induced self-thinning.

关键词： Relationship between relationships Selfthinning Forestry data Allometry Scots pine Douglasfir