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Sediment transport in headwaters of a volcanic catchment Kamchatka Peninsula case study

Frontiers of Earth science 2017年第3期11卷 565-578页

作者： Sergey R. CHALov Anatolii S. TSYPLENKov Jan PIETRON Aleksandra S. CHALovA Danila I. SHKOLNYI Jerker JARSJO Michael MAERKER faculty of Geography M. V. Lomonosov Moscow State University Moscow 119911 Russia Department of Physical Geography and the Bolin Centre for Climate Research Stockholm University Stockholm 10691 Sweden Department of Earth and Environmental sciences Pavia University Pavia 27100 Italy

Due to specific environmental conditions, headwater catchments located on volcanic slopes and valleys are characterized by distinctive hydrology and sediment transport patterns. However, lack of sufficient monitoring causes that the governing processes and patterns in these areas are rarely well understood. In this study, spatiotemporal water discharge and sediment transport from upstream sources was investigated in one of the numerous headwater catchments located in the lahar valleys of the Kamchatka Peninsula Sukhaya Elizovskaya River near Avachinskii and Koryakskii volcanoes. Three different subcatchments and corresponding channel types （wandering rivers within lahar valleys, mountain rivers within volcanic slopes and rivers within submountain terrains） were identified in the studied area. Our measure- ments from different periods of observations between years 2012-2014 showed that the studied catchment was characterized by extreme diurnal fluctuation of water discharges and sediment loads that were influenced by snowmelt patterns and high infiltration rates of the easily erodible lahar deposits. The highest recorded sediment loads were up to 9-104 mg/L which was related to an increase of two orders of magnitude within a one day of observations. Additionally, to get a quantitative estimate of the spatial distribution of the eroded material in the volcanic substrates we applied an empirical soil erosion and sediment yield model - modified universal soil loss equation （MUSLE）. The modeling results showed that even if the applications of the universal erosion model to different non-agricultural areas （e.g., volcanic catchments） can lead to irrelevant results, the MUSLE model delivered might be acceptable for non-lahar areas of the studied volcanic catchment. overall the results of our studyincrease our understanding of the hydrology and asso- ciated sediment transport for prediction of risk manage- ment within headwater volcanic catchments.

关键词： sediment transport volcanoes lahars Kam-chatka Peninsula MUSLE erosion

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Effects of Thinning and Litter Fall Removal on Fine Root Production and soil Organic Carbon Content in Masson Pine Plantations

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Pedosphere 2010年第4期20卷 486-493页

作者： TIAN Da-Lun PENG Yuan-Ying YAN Wen-De FANG Xi KANG Wen-Xing WANG Guang-Jun CHEN Xiao-Yong Forest Ecology Section Faculty of Life Sciences Central South University of Forestry and Technology Changsha 410006（China） Biology Program Department of Health and Science College of DuPage IL （USA） Biology Program College of Arts and Science Governors State University IL （USA）

soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecosystem in terms of water and nutrient uptake. In this study the effects of thinning and litter fall removal on fine root production and soil organic carbon content were examined in 20-year-old Masson pine (Pinus resinosa) plantations in Huitong, Hunan Province of China in the growing seasons of 2004 and 2005. The results showed that fine root production was significantly lower in the thinning plots than in the control plots, with a decrease of 58% and 14% in 2004 and 2005 growing seasons, respectively. Litter fall removal significantly increased fine root production by 14% in 2004. soil temperature (Tsoil) and soil moisture (Msoil) were higher in the thinning plots than those in the controls. Litter fall removal had significant effiects on Tsoil and Msoil. soil organic carbon content was higher in the thinning plots but was lower in the plots with litter fall removal compared with that in the controls. Our results also indicated that annual production of fine roots resulted in small carbon accumulation in the upper layers of the soil, and removal of tree by thinning resulted in a significant increase of carbon storage in Masson pine plantations.

关键词：马尾松人工林有机碳含量土壤管理凋落物细根生产秋季间伐

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Integrated watershed management:evolution,development and emerging trends

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Journal of Forestry Research 2016年第5期27卷 967-994页

作者： Guangyu Wang Shari Mang Haisheng Cai Shirong Liu Zhiqiang Zhang Liguo Wang John L.Innes faculty of Forestry University of British Columbia College of Land Resources and Environment Jiangxi Agriculture University Key Laboratory of Forest Ecology and Environment of state Forestry Administration Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry Key Laboratory of soil and Water Conservation and Desertification Combating Ministry of EducationBeijing Forestry University

Watershed management is an ever-evolving practice involving the management of land, water, biota, and other resources in a defined area for ecological, social, and economic purposes. In this paper, we explore the following questions： How has watershed management evolved？ What new tools are available and how can they be integrated into sustainable watershed management？ To address these questions, we discuss the process of developing integrated watershed management strategies for sustainable manage- ment through the incorporation of adaptive management techniques and traditional ecological knowledge. We address the numerous benefits from integration acrossdisciplines and jurisdictional boundaries, as well as the incorporation of technological advancements, such as remote sensing, GIS, big data, and multi-level social-eco- logical systems analysis, into watershed management strategies. We use three case studies from China, Europe, and Canada to review the success and failure of integrated watershed management in addressing different ecological, social, and economic dilemmas in geographically diverse locations. Although progress has been made in watershed management strategies, there are still numerous issues impeding successful management outcomes; many of which can be remedied through holistic management approaches, incorporation of cutting-edge science and technology, and cross-jurisdictional coordination. We conclude by high- lighting that future watershed management will need to account for climate change impacts by employing techno- logical advancements and holistic, cross-disciplinary approaches to ensure watersheds continue to serve their ecological, social, and economic functions. We present three case studies in this paper as a valuable resource for scientists, resource managers, government agencies, and other stakeholders aiming to improve integrated watershed management strategies and more efficiently and successfully achieve ecological and socio-economic ma

关键词： Adaptive management Climate change impacts Social-ecological systems analysis Traditional ecological knowledge Watershed management

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Copper pollution decreases the resistance of soil microbial community to subsequent dry–rewetting disturbance

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Journal of Environmental sciences 2016年第1期28卷 155-164页

作者： Jing Li Jun-Tao Wang Hang-Wei Hu Yi-Bing Ma Li-Mei Zhang Ji-Zheng He state Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences faculty of veterinary and Agricultural sciences The University of Melbourne National soil Fertility and Fertilizer Effects Long-term Monitoring Network Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences

Dry–rewetting（DW） disturbance frequently occurs in soils due to rainfall and irrigation, and the frequency of DW cycles might exert significant influences on soil microbial communities and their mediated functions. However, how microorganisms respond to DW alternations in soils with a history of heavy metal pollution remains largely ***, soil laboratory microcosms were constructed to explore the impacts of ten DW cycles on the soil microbial communities in two contrasting soils（fluvo-aquic soil and red soil）under three copper concentrations（zero, medium and high）. Results showed that the fluctuations of substrate induced respiration（SIR） decreased with repeated cycles of DW alternation. Furthermore, the resistance values of substrate induced respiration（RS-SIR）were highest in non-copper-stressed（zero） soils. Structural equation model（SEM） analysis ascertained that the shifts of bacterial communities determined the changes of RS-SIR in both soils. The rate of bacterial community variance was significantly lower in noncopper-stressed soil compared to the other two copper-stressed（medium and high） soils,which might lead to the higher RS-SIR in the fluvo-aquic soil. As for the red soil, the substantial increase of the dominant group WPS-2 after DW disturbance might result in the low RS-SIR in the high copper-stressed soil. Moreover, in both soils, the bacterial diversity was highest in non-copper-stressed soils. Our results revealed that initial copper stress could decrease the resistance of soil microbial community structure and function to subsequent DW disturbance.

关键词： Copper stress Dry–rewetting disturbance Bacterial community Substrate induced respiration Resistance

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Photosynthetic pigments accumulation and some growth indices of cowpea, maize and tomato in response to interspecific and intraspecific competition stress

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Research in Cold and Arid Regions 2017年第2期9卷 120-126页

作者： Ezekiel Dare Olowolaju Adekunle Ajayi Adelusi Department of Botany Faculty of Science Obafemi Awolowo University Ile-Ife Osun state Nigeria

This study aimed at investigating the photosynthetic pigment accumulation and some growth indices of cowpea, maize and tomato in response to interspecific and intraspecific competition stress. The study was carried out under a screen-house to minimize extraneous factors such as pests and rodents using a randomized complete block design(RCBD). Seeds of cowpea, maize and tomato were collected from the Department of Crop Production and Protection, faculty of Agriculture,Obafemi Awolowo university, Ile Ife, Osun state, Nigeria. These seeds were planted at a depth of about 3 mm below the soil. The seeds were sown at the rate of six seeds per pot in the monoculture, while in the pots designed for the mixed culture of maize and cowpea, maize and tomato, cowpea and tomato, three seeds of each plant were sown. Two seeds of each plant were sown in the pots with the three crops. The treatments were then supplied with 500 m L of tap water in the morning and in the evening respectively until the seedlings become fully established. The photosynthetic pigments were determined spectrophotometrically with three replicates. Plant growth indices were determined according to Hunts(1978) using leaf area and dry matter data collected at four and six weeks after planting. Statistical analysis was performed using statistical analytical software SAS version 9.2. The results indicated that photosynthetic pigments accumulation(Chlorophyll a, b and carotenoid) in maize(15.98, 23.92 and 44.72 μM), Chlorophyll b and carotenoid in tomato plants(12.48 and 1,178.7μM) in the sole stands were more than the mixed culture of maize with cowpea and tomato(7.195, 14.74 and 0.00 μM).Also, total Chlorophyll in maize(1,127.8 μM), Chlorophyll a and total Chlorophyll in tomato(3.95 and 1,317.5 μM) in the mixed culture were more than in the sole culture of maize(1,030.9 μM) and tomato plants(-9.40 and 546.3 μM). The different photosynthetic pigments accumulated in cowpea were greatly enhanced in the mixed cultu

关键词： pigments competition growth monoculture intercropping

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High starter phosphorus fertilization facilitates soil phosphorus turnover by promoting microbial functional interaction in an arable soil

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Journal of Environmental sciences 2020年第8期32卷 179-185页

作者： Hongzhe Li Qingfang Bi Kai Yang Simon bo Lasson Bangxiao Zheng Li Cui Yongguan Zhu Kai Ding Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China university of the Chinese Academy of sciences Beijing 100049China Key Laboratory of Subtropical soil science and Plant Nutrition of Zhejiang Province College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Department of Plant and Environmental sciences Faculty of ScienceUniversity of CopenhagenThorvaldsensvej 401871 FrederiksbergDenmark faculty of Biological and Environmental sciences Ecosystems and Environment Research Programme Niemenkatu 73FI-15140 University of HelsinkiFinland state Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Microbial phosphorus(P)turnover is critical in C utilization efficiency in *** is therefore necessary to understand the P mobilization processes occurring during P fertilization in order to ensure both crop yield and environmental ***,we established a controlled pot experiment containing soil amended with three different levels of starter P fertilizer and collected soil samples after 30,60,and 90 days of *** microbial element cycling(QMEC)smart chip technology and 16S rRNA gene sequencing were used to investigate functional gene structures involved in carbon,nitrogen and P cycling and the bacterial community composition of the collected *** P fertilization did not significantly affect the structure of the soil microbial community,some rare microbiota were changed in particular phosphorus-solubilizing bacteria were enriched at the high P fertilization level,suggesting that the rare taxa make an important contribution to P turnover.P fertilization also altered the functional gene structure,and high P concentrations enhanced the functional gene diversity and *** redundancy analysis further revealed that changes in rare taxa and functional genes of soil microorganisms drive the alteration of soil P *** findings extend our understanding of the microbial mechanisms of P turnover.

关键词： Quantitative microbial element cycling(qmec)smart chip Functional genes Rare microbiota

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Design and experiment of fuzzy-PID based tillage depth control system for a self-propelled electric tiller

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 116-125页

作者： Maohua Xiao Ye Ma Chen Wang Junyun Chen Yejun Zhu Petr Bartos Guosheng Geng College of Engineering Nanjing Agricultural UniversityNanjing 210031China faculty of Agriculture University of South BohemiaStudentska 1668Czech

The research on the self-propelled electric tiller is vital for further improving the quality and efficiency of greenhouse rotary tillage operation,reducing the work intensity and operation risk of operators,and achieving environmentally friendly *** of the existing self-propelled tillers rely on manual adjustment of the tillage ***,the consistency and stability of the tillage depth are difficult to *** this study,the automatic control method of tillage depth of a self-propelled electric tiller is investigated.A method of applying the fuzzy PID(Proportional Integral Derivative)control method to the tillage depth adjustment system of a tiller is also proposed to realize automatic *** system uses the real-time detection of the resistance sensor and angle *** controller runs the electronically controlled hydraulic system to adjust the force and position *** fuzzy control algorithm is used in the operation error control to realize the double-parameter control of the tillage *** simulation and experimental verification of the system are *** show that the control system applying fuzzy PID can improve the soil breaking rate by 3%in the operation process based on reducing the stability variation of tillage depth by 24%.The control strategy can reach the set value of tillage depth quickly and *** can also meet the requirement of tillage depth consistency during the operation.

关键词： Fuzzy PID Self-propelled electric tiller Tillage depth Electro-controlled hydraulic system Comprehensive adjustment of force and position

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Comparison of Pile-soil-Structure Interaction Modeling Techniques for A 10-MW Large-Scale Monopile Wind Turbine Model Under Wind and Wave Conditions

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China Ocean Engineering 2023年第3期37卷 471-483页

作者： ZENG Yu-xin ZHANG Xiao-ming ZHANG Li-xian SHI Wei WANG Wen-hua LI Xin Hunan Provincial Key Laboratory of Key Technology on Hydropower Development Changsha 410014China PowerChina Zhongnan Engineering Corporation Limited Changsha 410021China state Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China DeepWater Engineering Research Centre Dalian University of TechnologyDalian 116024China Institute for Earthquake Engineering Faculty of Infrastructure EngineeringDalian University of TechnologyDalian 116024China

Considering the large diameter effect of piles,the influence of different pile-soil analysis methods on the design of monopile foundations for offshore wind turbines has become an urgent problem to be *** different pile-soil models were used to study a large 10 MW monopile wind *** modeling the three models in the SACS software,this paper analyzed the motion response of the overall structure under the conditions of wind and *** to the given working conditions,this paper concludes that under the condition of independent wind,the average value of the tower top x-displacement of the rigid connection method is the smalle st,and the standard deviation is the smallest under the condition of independent *** results obtained by the p-y curve method are the most conservative.

关键词： large-scale monopile offshore wind turbine pile-soil model wind-wave load combination

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淡水蜗牛视觉系统的输入与输出通路(英文)

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Zoological Research 2011年第4期32卷 403-420页

作者： Oksana P Tuchina valery v Zhukov victor Benno Meyer-Rochow School of Engineering and science Jacobs UniversityBremen D-28759Germany Department of Agricultural and soil Ecology Faculty of Bioresources and Natural UsageKaliningrad State Technical UniversityKaliningrad 236000Russia

通过神经生物素在视神经上的逆行性传输对淡水蜗牛(Planorbarius corneus)视网膜及中央神经节的输入、输出神经元进行标记。由于没有发现突触联系,所以至少一部分光感受细胞的轴突可被视为直接参与形成视神经。这些神经元的轴突进入大... 详细信息

通过神经生物素在视神经上的逆行性传输对淡水蜗牛(Planorbarius corneus)视网膜及中央神经节的输入、输出神经元进行标记。由于没有发现突触联系,所以至少一部分光感受细胞的轴突可被视为直接参与形成视神经。这些神经元的轴突进入大脑神经节形成密集的细传入神经纤维束-视神经堆。传出神经元则存在于除颊部以外的所有神经节。一些上行轴突在大脑神经节处分叉,通过脑-脑联合,到达对侧眼并在眼杯处形成分枝。部分传出神经元的轴突也投射于不同的外周神经,如:***,pallialis dexter,pallialis sinister internus et externus。五羟色胺能纤维和FMRF-酰胺能纤维均存在于视神经上,且这些纤维隶属于只投射在同侧眼的中央神经元。它们形成了位于眼杯处的丰富曲张结构及视网膜核心层,并且可能有助于调节视网膜对光的敏感性。

关键词：腹足纲神经系统眼逆行性传输五羟色胺 FMRF-酰胺

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Integrate ecosystem services into socio-economic development to enhance achievement of sustainable development goals in the post-pandemic era

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Geography and Sustainability 2021年第1期2卷 68-73页

作者： Caichun Yin Wenwu Zhao Francesco Cherubini Paulo Pereira state Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Industrial Ecology Programme and Department of Energy and Process Engineering Norwegian University of Science and Technology(NTNU)NorwegianNorway Environmental Management Center Mykolas Romeris UniversityVilnius 08303Lithuania

The CovID-19 pandemic has stalled and rolled back progress on Sustainable Development Goals(SDGs).Ecosys-tem services(ESs),defined as the contributions of ecosystems to human well-being,underpin the achievement of *** promote SDG achievement in post-pandemic era,we teased out the links between ESs and SDGs while examining the impact of *** found that ESs benefited all SDGs,yet man-made pressures led to degra-dation of ecosystems and their *** is broad consensus that the virus lurks in degraded ecosystems and generates spillover due to human *** pandemic and global lockdown/restriction disrupted the flow of ESs and altered human ESs demand,threatening the efforts for the *** suggested:1)to study the association and traceability of ESs-SDGs under the pandemic;2)to prioritize pressing issues such as health care,livelihood,and resource security and in the long run,we should promote human-nature harmony to achieve the SDGs;and 3)to enhance ESs and to promote the SDGs through local community efforts,ESs accounting,and ecosystem *** paper provides insights into the importance of ESs to the SDGs and the ways to integrate ESs into socio-economic development to promote the SDG achievement after the pandemic.

关键词： Ecosystem services(ESs) Sustainable development goals(SDGs) CovID-19 pandemic Socio-economic development Human-nature relationship

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