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The impact of biotic and abiotic factors on the distribution of surface sediment dinoflagellate cyst assemblages on the Nanji Island in the East China Sea

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Acta Oceanologica Sinica 2019年第1期38卷 160-171页

作者： Han Gao Shengpao You Xiangdong Lei Yunpu Xiao Haifeng Gu Mengmeng Tong Ocean College Zhejiang University Nanji Marine Environment Monitoring Station Ministry of Natural Resources Pingyang county Marine and Fisheries bureau Third Institute of Oceanography Ministry of Natural Resources

The dinoflagellate cyst assemblages on the Nanji Island in the East China Sea, are documented at the first time to construct a quantitative overview of the cyst bank from 2014 to 2015. Thirty-four morphotypes from six groups are identified and quantified at eight sampling sites around the island, including a high proportion of potentially toxigenic species(14%). Autotrophic dinocysts constitute 74% of the total cyst counts, which is relatively low(two to thirty-three per millilitre sediment) compared with previous studies in adjacent areas. Scrippsiella trochoidea and Protoperidinium avellana are the most abundant autotrophic and heterotrophic species, respectively. A multivariate analysis is performed to assess associations between dinocysts and abiotic or biotic *** among seasons is evident in the detrended correspondence analysis(DCA) ordination plot, while a spatial pattern is not clearly revealed despite heterogeneity of the hydrodynamic conditions between sampling sites. Soluble reactive phosphate, the ratio of nitrogen to phosphorus concentrations and Karenia mikimotoi bloom are the three factors significantly(P<0.05) related to surface sediment cyst assemblage defined by the canonical correspondence analysis(CCA), highlighting the importance of nutrient regime to a dinocyst distribution in this area. Although attempts to address the origin of HAB events in recent years using seed banks have failed, knowledge can be valuable for further investigation of dinocyst dynamics and potential toxin threats on the Nanji Island.

关键词： dinoflagellate cyst Nanji Island nutrients harmful algal blooms

Closing the nitrogen use efficiency gap and reducing the environmental impact of wheat-maize cropping on smallholder farms in the Guanzhong Plain,Northwest China

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Journal of Integrative Agriculture 2019年第1期18卷 169-178页

作者： Lü Feng-lian HOU Miao-miao ZHANG Hong-tao Asif Khan Muhammad Ayaz QIANGJIU Ciren HU Chang-lu YANG Xue-yun SUN Ben-hua ZHANG Shu-lan College of natural resources and Environment Northwest A&F University/Key Laboratory of Plant Nutrition and the Agro-environment in Northwest ChinaMinistry of Agriculture Agriculture and Husbandry bureau of Cuona county Agriculture and Husbandry Bureau of Cuona County

A high crop yield with the minimum possible cost to the environment is generally ***,the complicated relationships among crop production,nitrogen(N) use efficiency and environmental impacts must be clearly *** conducted a series of on-farm N application rate experiments to establish the linkage between crop yield and N_2 O emissions in the Guanzhong Plain in Northwest *** also examined crop yield,partial factor productivity of applied N(PFPN) and reactive N(Nr) losses through a survey of 1 529 and 1 497 smallholder farms that grow wheat and maize,respectively,in the *** optimum N rates were 175 and 214 kg ha^(-1) for winter wheat and summer maize,respectively,thereby achieving the yields of 6 799 and 7 518 kg ha^(-1),correspondingly,with low N_2 O emissions based on on-farm N rate *** the smallholder farms,the average N application rates were 215 and 294 kg ha^(-1) season^(-1),thus producing 6 490 and 6 220 kg ha^(-1) of wheat and maize,*** corresponding PFPN values for the two crops were 36.8 and 21.2 kg N kg^(-1),and the total N_2 O emissions were 1.50 and 3.88 kg ha^(-1),*** N balance,large Nr losses and elevated N_2 O emissions could be explained by the overdoses of N application and low grain yields under the current farming *** crop yields,N application rates,PFPN and total N_2 O for wheat and maize were 18 and 24% higher,42 and 37% less,75 and 116% higher,and 42 and 47% less,correspondingly,in the high-yield and high-PFPN group than in the average smallholder *** conclusion,closing the PFPN gap between the current average and the value for the high-yield and high-PFPN group would increase crop production and reduce Nr losses or the total N_2 O emissions for the investigated cropping system in Northwest China.

关键词： N fertiliser grain yield PFPN N balance reactive nitrogen losses N2O emission

Urban Development Boundary Simulation Based on“Double Evaluation”and FLUS Model

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Journal of Geodesy and Geoinformation Science 2022年第2期5卷 7-18页

作者： Xuchen JIANG Meng WANG Gang XU Bingwang FANG Kun QIN Rui XIAO School of Remote Sensing and Information Engineering Wuhan UniversityWuhan 430079China Wuhan planning&Design Institute Wuhan 430072China natural resources and planning bureau of Zigui county Ministry of Natural ResourcesYichang 415323China

The delimitation of urban development boundaries plays an important role in optimizing the nation land space.“Double evaluation”is one of the important means to study and predict the scale of new construction land in the future and to determine the spatial distribution of urban construction *** study combines the“double evaluation”with the FLUS(Future Land-Use Simulation)model to study the delimitation of the urban development boundary of *** results show that:(1)the“double evaluation”method comprehensively considers the carrying capacity of the resource environmental bear and the suitability of urban development;(2)the FLUS model can better couple the“double evaluation”method for Land Use/Land Cover(LULC)suitability evaluation,Land Use/land Cover Change(LUCC)simulation and urban development boundary delineation,and the overall accuracy of the simulation reaches 96%;(3)according to the requirements of relevant national policies,this study divides the urban development boundary of the study area into concentrated construction areas,elastic development areas and special purpose *** function-based division can meet the requirements of urban flexible development,ecological protection and urban *** research combines the FLUS model,which is widely used in the simulation of LUCC,with the double evaluation method used in China’s new round of land and space planning to obtain the result of the urban development *** result is consistent with the existing plan of the study area.

关键词： urban development boundaries double evaluation FLUS(Future Land-Use Simulation)model land spatial layout optimization

Deformation characteristics and thresholds of the Tanjiawan landslide in the Three Gorges Reservoir Area,China

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Journal of Mountain Science 2022年第5期19卷 1370-1385页

作者： ZHANG Fu-ling DENG Mao-lin YI Qing-lin LU Shu-qiang ZHENG Wei-jun HUANG Hai-feng ZHU Xing Hubei Geological Disaster Prevention and Control Engineering Technology Research Center China Three Gorges UniversityYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China natural resources and planning bureau ofzigui county Yichang 443002China

Since the first impoundment of the Three Gorges Reservoir(TGR)in China in 2003,more than 5000 landslides including potential landslides were *** this paper,a deep-seated active landslide in TGR area was *** years’monitoring data and field investigations from 2006 to 2020 were used to analyze the deformation characteristics,influencing factors,and meteohydrological *** landslide showed a none-overall periodic movement pattern featuring acceleration during long-duration rainfall and rapid transition to constant creep after rainfall *** secondary sliding masses,No.1 and No.2,were defined via field *** reservoir has no impact on the deformation whereas long-duration-low-intensity rainfall is the main *** present,the cumulative displacements of the main sliding mass range from 0.9 to 3.2 m,and the deformation during the rainy season is gradually *** boundary of this landslide was formed,and the boundary of No.2 sliding mass became *** probability of the failure of sliding mass No.2 is very high under the conditions of continuous *** 15-day antecedent rainfall combined with 4-day cumulative rainfall could be the rainfall threshold which could be associated with the groundwater level S1 of 294 m above sea level for forecasting large deformation of Tanjiawan landslide.

关键词： Three Gorges Reservoir Deformation characteristics Deep-seated landslide Rainfall threshold Groundwater threshold

The Paleozoic Huoshenmiao iron skarn deposit in the Tongbai area of North Qinling Orogen,China:Insights from garnet U-Pb dating and geological constraints

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Science China Earth Sciences 2021年第12期64卷 2172-2189页

作者： Mingchun CHAI Hao HU Jianwei LI Shiguang DU Linfeng HOU School of Earth resources China University of GeosciencesWuhan430074China State Key Laboratory of Geological Process and Mineral resources China University of GeosciencesWuhan430074China Pu’er natural resources and planning bureau Pu’er665000China

The Qinling Orogen is a composite orogenic belt that can be subdivided into the North and South Qinling,broadly separated by the Shangdan suture *** two orogenic belts were generated by subduction-collisional processes in the Early Paleozoic and Late Triassic,*** the Late Jurassic to Early Cretaceous,the eastern portion of the Qinling Orogen was tectonically reactivated due to westerly subduction of the Izanagi plate underneath the East China continental *** Qinling Orogen is well-endowed with numerous Au,Mo,Ag-Pb-Zn deposits that predominantly formed in the Late Triassic to Early Cretaceous,with rare Paleozoic varieties *** this study,we present garnet and zircon U-Pb dating results to show that the Huoshenmiao iron skarn deposit in the Tongbai area of North Qinling orogenic belt formed in the Early Silurian and is genetically related to subduction-related *** Huoshenmiao deposit consists of lenticular and stratiform orebodies that contain massive or densely disseminated magnetite variably associated with garnet,diopside,epidote,hornblende,and *** from iron ores are andradite and grossular in composition(Ad_(83.1)Gr_(13.3)-Ad_(86.5)Gr_(10.2))and characterized by enrichment in light rare earth elements(ΣLREE=57.85-103.82 ppm)and depletion in heavy rare earth elements(ΣHREE=5.50-11.34 ppm),with significantly positive Eu and Ce anomalies(δEu of 1.09-1.89 andδCe of 1.39-1.69).These compositional signatures are distinctly different from those of garnets in the ore-hosting metamorphic rocks that are typically dominated by almandine,spessartine and grossular(Al_(47.4)Sp_(30.4)Gr_(13.8)-Al_(51.9)Sp_(24.8)Gr_(17.6)),depleted in LREE(0.14-0.69 ppm),enriched in HREE(95.68-841.60 ppm)and have pronounced negative Eu anomalies(δEu=0.24-0.51).In addition,garnets from iron ores of the Huoshenmiao deposit contain abundant daughter mineral-bearing,multiphase fluid inclusions,further confirming their hydrothermal origin

关键词： Huoshenmiao iron skarn deposit Tongbai area North Qinling orogenic belt Paleozoic metallogeny

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Integrated data-model-knowledge representation for natural resource entities

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International Journal of Digital Earth 2022年第1期15卷 653-678页

作者： Yulin Ding Zhaowen Xu Qing Zhu Hankan Li Yan Luo Ying Bao Lingjun Tang Sen Zeng Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople's Republic of China Municipal planning & Land Estate Information Center Shenzhen Municipal Bureau of Planning and Natural ResourcesShenzhenPeople's Republic of China Information Center Department of Natural Resources of Sichuan ProvinceChengduPeople's Republic of China

The unified management and planning of national or provincial natural resources distributed both aboveground and underground have become increasingly *** depictions of natural resource elements and their interactions are key to achieving integrated and systematic management of natural ***,current spatiotemporal data models are based only on data descriptions,attribute records,and other model knowledge of a more general basis,without intuitively describing relationships between these elements and natural *** paper,therefore,proposes an integrated data-model-knowledge representation model to explicitly describe the time,space,and interaction of natural resource entities through an integrated knowledge ***,this study constructs a conceptual model using the aspects of semantics,scale,and data-model-knowledge,thereby explicitly describing the relationships of natural ***,a logical model of natural resource representation is proposed,that is integrated with time,space,attributes,and ***,taking the management of water resources as an example,this paper realizes the meticulous presentation of the levels of detail and rich semantic relations of natural resource *** findings of this study lay the foundation for a more efficient,precise,and lucid perception of the distribution laws and complicated interactional relationships of natural resources,both aboveground and underground.

关键词： natural resources data-model-knowledge interactional relationships

Molecular characterization and functional analysis of daf-8 in the pinewood nematode,Bursaphelenchus xylophilus

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Journal of Forestry Research 2022年第2期33卷 689-698页

作者： Jinghan Wang Huan Hong Rong Xie Jingjing Ji Kai Guo Liqun Bai Jia Tang Hongshi Yu Jianren Ye Jiafu Hu Nanjing Forestry University Nanjing 210037China Zhejiang Agricultural and Forestry University Hangzhou 311300China Yuhuan natural resources and planning bureau Taizhou 317600China School of BioSciences The University of MelbourneParkvilleVIC 3010Australia

Bursaphelenchus xylophilus,causal agent of pine wilt disease,causes extensive damage ***-gies are needed to inhibit population growth or block the spread of the invasive nematode to control pine wilt *** gene daf-8 plays crucial roles in larval develop-ment and dauer formation in Caenorhabditis elegans,but little is known about its orthologue in *** the present molecular characterization and functional analysis of daf-8 in ***(Bx-daf-8),RT-qPCR showed that the expression of Bx-daf-8 gradually increased during the embryonic stage,peaked in the second-stage juvenile(J2),then dramatically dropped in the J3,and remained at that low level for the rest of its ***-daf-8-transgenic *** was employed to mimic the spatiotemporal expression of Bx-daf-8,which was expressed close to the pharynx during early embryogenesis and weakly throughout the whole body during late *** was observed in head neurons and tail ganglions throughout all postembryonic *** embryos were severely abnormal,and hatching rate decreased sharply after Bx-daf-8 ***-16-1 and da-f16-2,downstream genes in the IIS pathway,also dropped sharply after Bx-daf-8 *** propose that TGFβmay crosstalk with the IIS pathway upstream of Bx-daf-16 and that daf-8 may act as a master regulator of daf-16 in ***,knockdown of Bx-daf-8 did not lead to constitutive developmental arrest at the dauer larval stage,indicating that dauer entry in *** might be controlled by several genes and is more complicated than in ***-daf-8 alone did not control the dauer entry in ***,but it was indispensable for embryogen-esis,providing a potential target for suppressing population growth of ***.

关键词： Daf-8 Expression pattern RNAi Embryogenesis Bursaphelenchus xylophilus

Spatiotemporal evolution of ecosystem service value and topographic gradient effect in the Da-Xiao Liangshan Mountains in Sichuan Province,China

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Journal of Mountain Science 2023年第8期20卷 2344-2357页

作者： JIN Tao CHEN Yang SHU Bo GAO Min QIU Jian School of Architecture Southwest Jiaotong UniversityChengdu 611756China Leshan Municipal bureau of planning and natural resources Leshan 614000China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in *** study selected a total of six periods of land use land cover(LULC)data from 1995 to 2020,to estimate the ecosystem service value(ESV)and analyzed its spatiotemporal evolution and topographic gradient *** results showed that:(1)The ESV increased by 1.1 billion yuan,with an increase rate of 1.47%from 1995 to *** time periods,2005–2010 and 2015–2020,showed more significant increases than other periods.(2)The elevation and slope of mountainous areas determine the type of land use and further influence the spatial pattern of ESV.(3)Although woodland and grassland are the main land use types of the study area(more than 90%),the hydrological regulation function of the water area partially compensated for the impact of the encroachment of the built-up area on the ESV of grassland.(4)The spatial distribution of ESVs showed an inverted V-shaped characteristic as the topographic gradient increased,with the dominant position being the 5th topographic gradient ***,this study provided relevant recommendations for ecosystem protection and *** findings of this study clarified the influence of topographical factors on the spatial differentiation of ESV and provided novel insights into ecosystem protection.

关键词： Ecosystem service value(ESV) Dynamic evolution Terrain gradient effect Spatial pattern Liangshan Yi region

Driving Mechanism of Cultivated Land Transition in Yantai Proper,Shandong Province,China

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Chinese Geographical Science 2015年第3期25卷 337-349页

作者： QIN Weishan ZHANG Yifeng LI Guangdong Institute of Geographic Sciences and natural resources Research Chinese Academy of Sciences Geography and planning School of Ludong University

Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the quantitative perspective. Based on the vector data of land use in 1990, 2000 and 2009 of Yantai Proper, Shandong Province China, 11 explanatory variables were chosen from two aspects: the elevation, slope, cost distance to major water area and cost distance to minor water area, which presented physical factors; cost distance to district center, cost distance to town center, cost distance to city expansion center, cost distance to major roads, cost distance to city roads, cost distance to county roads and cost distance to rural roads, which presented the socio-economic factors. Combined with spatial analysis tools and Logistic regression analysis model, we construct Logistic regression analyses with four objectives that were urban construction land, rural residential land, orchard and other lands. The results show that, cost distance to district center, cost distance to town center, cost distance to city expansion center and cost distance to city roads are the significant explanatory variables for the transition of cultivated land into urban construction land. The main explained factors on the transition of cultivated land into rural residential land are slope, cost distance to town center, cost distance to county roads and cost distance to rural roads. Slope, cost distance to minor water area, cost distance to town center, cost distance to county roads and cost distance to rural roads are the significant explanatory variables for the transition of cultivated land into orchard land. Elevation, slope, cost distance to major water area and cost distance to minor water area are the main explanatory variables on the transition of cultivated land into other land uses.

关键词： cultivated land use transition driving mechanism Yantai Proper China