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From the water sources of the Tibetan Plateau to the ocean:State of nutrients in the Changjiang linked to land use changes and climate variability

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Science China Earth Sciences 2022年第11期65卷 2127-2174页

作者： Jing ZHANG Guosen ZHANG Yanan DU Anyu ZHANG Yan CHANG Yingchun ZHOU Zhuoyi ZHU Ying WU Zaifeng ZHANG Sumei LIU State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China Yangze River Estuary Survey Bureau of hydrology and Water Resource CWRCShanghai 200136.China KLATASDS-MOE School of StatisticsEast China Normal UniversityShanghai 200241China Nantong Environmental Monitoring Center Ministry of Ecology and EnvironmentNantong 226006China Key Laboratory of Marine Chemistry Theory and Technology Ocean University of ChinaQingdao 266100China School of Oceanography Shanghai Jiao Tong University Shanghai 200030China

Anthropogenic activity is an important driver of changes in the chemistry of nutrients(N,P,and Si)over watersheds at the sub-continental scale(e.g.,106km~2)and can markedly modify their seaward fluxes to the global *** the present study,we reviewed the current status of nutrient chemistry in Changjiang(Yangtze River)based on data collected through 11 expeditions along a river course spanning 4,500 km and 15–20 major tributaries during 1997–2016 as well as monthly monitoring at the river mouth since *** data were analyzed together with published results in the literature to synthesize the recent developments and current state of nutrients in the *** published results from the Qinghai-Tibetan Plateau head waters were included to realize the systematics of nutrients for the whole drainage ***,we showed that tributaries of the upper reaches of watersheds collectively determine the regime with high concentration and skewed species ratio of nutrients in the Changjiang mainstream,producing profound effects over a water course of 2,000–2,500 km further downstream and until the river ***,using data across the Three Gorges Reservoir(TGR)during 2003–2016,we evaluated the trapping and/or amplifying effects of the Three Gorges Dam(TGD)on nutrient ***-influenced river delta contributed an additional 20%dissolved inorganic phosphorus and 5–10%dissolved inorganic nitrogen and dissolved silicates to the seaward flux,dramatically affecting the stoichiometry of nutrients at the river ***,based on compiled data on supply and export,legacy nutrients were *** nitrogen and phosphorus are in the accumulation phase over the watersheds,and the legacy nutrient fluxes are much higher than the annual riverine seaward ***,we demonstrated that the seaward fluxes of anthropogenic nutrients from the Changjiang exceed those from other top 10 largest rivers on this planet,which can be attributed to land use changes

关键词： Changjiang Nutrient chemistry Species ratio Fluxes Global river systems Hysteresis effect Legacy contributions

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Impact of the Yellow River capture on the paleoenvironmental changes of Hongze Lake, China

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International Journal of Sediment Research 2023年第4期38卷 503-515页

作者： Hongwu Tang Ming Gao Saiyu Yuan Huiming Zhang Yang Xiao Fuxin Zhang Kun Zhang State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai University Institute of Water Science and Technology Hohai University

The Yellow River(YR) capture of the Huai River had a profound effect on the landscape evolution,ecology, and social development in China, disrupting the evolution of some vital shallow floodplain *** of the absence of lacustrine sediment provenance analysis, previous studies were inadequate in distinguishing the influence of YR capture on paleoenvironmental changes in these lakes, especially on landscape evolution, redox conditions, lake level changes, and organic productivity. The current study aims to use X-ray fluorescence-core scanning(XRF-CS) and multivariate statistics on a 9.8 m sediment core from Hongze Lake(HZL), China, to analyze the impact of the YR capture on the lake’s paleoenvironmental changes and the sediment provenance simultaneously. High-resolution images, magnetic susceptibility, and XRF-based multi-element data were obtained using a GEOTEK Multi-Sensor Core Logger. The calcium(Ca) content indicates the presence of YR sediment in HZL, given the high Ca content in YR sediment and the identification of mainly exogenous sources of Ca in HZL. The high values of Ca indicate that 48.7% of the sediment in the center of HZL is related to the YR’s incursion. Periods of higher Ca content coincide with periods of higher oxygenation levels of the lake(as indicated by the ratio of manganese to titanium) and lower organic content in the lake sediment(as indicated by the ratio of incoherent to coherent scatter). These analyses reveal that the YR’s capture of HZL significantly increased the lake’s oxygen level. Furthermore, the decrease in the organic content of sediment tends to be the result of the accelerated deposition caused by the YR. The decrease in Ca content coincides with an increase in lake levels(as indicated by magnetic susceptibility). Thus, it can be inferred that the embankment on the eastern side of HZL, built to increase lake storage, has reduced the incursion frequency of the YR.

关键词： Yellow River capture Paleoenvironmental reconstruction XRF-CS Hongze Lake

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Influence of visual targets and landmarks on honey bee foraging and waggle dancing

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Insect Science 2020年第2期27卷 349-360页

作者： Bahram Kheradmand Julian Cassano Selena Gray James C.Nieh division of Biological Sciences Section of EcologyBehavior&EvolutionUniversity of California San DiegoLa JollaCaliforniaUSA

Animals use diverse sensory stimuli to navigate their environment and to recognize rewarding food *** bees use visual atributes of the targeted food source,such as its color,shape,size,direction and distance from the hive,and the landmarks around it to navigate during *** transmit the location information of the food source to other bees if it is highly *** investigate the relative importance of these attributes,we trained bees to feeders in two different *** the first experiment,we asked whether bees prefer to land on(a)a similar feeder at a different distance on the same heading or on(b)a visually distinct feeder located at the exact same *** found that,within a short foraging range,bees relied heavily on the color and the shape of the food source and to a lesser extent on its distance from the *** the second experiment,we asked if moving the main landmark or the feeder(visual target)influenced recruitment dancing for the *** found that foragers took longer to land and danced fewer circuits when the location of the food source,or a major landmark associated with it,*** results demonstrate that prominent visual atributes of food sources and landmarks are evidently more reliable than distance information and that foraging bees heavily utilize these visual cues at the later stages of their journey.

关键词： Apis mellifera foraging leaning navigation visual orientation

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Structure and floristic composition of old-growth wet evergreen forests of Nelliampathy Hills, Southern Western Ghats

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Journal of Forestry Research 2013年第1期24卷 37-46页

作者： V.S. Ramachandran K. Swarupanandan Forest ecology and Biodiversity Conservation division Kerala Forest Research InstitutePeechiThrissur-680653KeralaIndia.

We analyze the structure and composition of old-growth wet evergreen forest of Nelliampathy hills, the chain of hills lying immediately south of Palghat Gap, in the southern Western Ghats of India. We sampled 30 plots of 0.1 ha each （50 m × 20 m） at six locations enumerating all plants ？ 10 cm girth at breast height. We pooled the data and computed various structural parameters. There were 152 species of 120 genera and 51 families of the study area. Of these, 118 （77%） were trees, 24 were climbers （16%） and 10 were shrubs （7%）. Species richness varied from 58–99 per 0.5 ha sample and Shannon indices of diversity ranged from 4.4 to 5.2. Fifty-nine per cent （89 species） of the species were Indian Sub-continent elements and 34% （51 species） are endemic to the Western Ghats. Fifteen species are listed in various threat categories. Aglaia and Litsea were the most species-rich genera. Numbers of families ranged from 27–43 per 0.5 ha sample. Euphorbiaceae and Lauraceae were the most species-rich families. Stand density varied from 1714 to 2244 stems·ha？1 and basal area from 53.6 to 102.1 m2·ha？1. The vegetation was dominated by 3–6 species and six dominance patterns characterized the species composition within the hill complex. The old-growth evergreen forests of Nelliampathy exist as small fragments rich in biodiversity and can be used as benchmarks for comparison with disturbed forests.

关键词： Old-growth evergreen forest Nelliampathy Western Ghats species richness tree density relative abundance stand structure.

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Exogenous nitrogen input skews estimates of microbial nitrogen use efficiency by ecoenzymatic stoichiometry

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Ecological Processes 2023年 625-631页

作者： Lifei Sun Daryl L.Moorhead Yongxing Cui Wolfgang Wanek Shuailin Li Chao Wang CAS Key Laboratory of Forest ecology and Management Institute of Applied Ecology Chinese Academy of Sciences Department of Environmental Sciences University of Toledo Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University division of Terrestrial Ecosystem Research Center of Microbiology and Environmental Systems Science University of Vienna

Background Ecoenzymatic stoichiometry models（EEST） are often used to evaluate microbial nutrient use efficiency,but the validity of these models under exogenous nitrogen（N） input has never been clarified. Here, we investigated the effects of long-term N addition（as urea） on microbial N use efficiency（NUE）, compared EEST and18O-labeling methods for determining NUE, and evaluated EEST's theoretical assumption that the ratios of standard ecoenzymatic activities balance resource availability with microbial *** We found that NUE estimated by EEST ranged from 0.94 to 0.98. In contrast, estimates of NUE by the18O-labeling method ranged from 0.07 to 0.30. The large differences in NUE values estimated by the two methods may be because the sum of β-N-acetylglucosaminidase and leucine aminopeptidase activities in the EEST model was not limited to microbial N acquisition under exogenous N inputs, resulting in an overestimation of microbial NUE by EEST. In addition, the acquisition of carbon by N-acquiring enzymes also likely interferes with the evaluation of NUE by *** Our results demonstrate that caution must be exercised when using EEST to evaluate NUE under exogenous N inputs that may skew standard enzyme assays.

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Adjusting precipitation measurements from the TRwS204 automatic weighing gauge in the Qilian Mountains, China

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Journal of Mountain Science 2018年第11期15卷 2365-2377页

作者： ZHENG Qin CHEN Ren-sheng HAN Chun-tan LIU Jun-feng SONG Yao-xuan LIU Zhang-wen YANG Yong WANG Lei WANG Xi-qiang LIU Xiao-jiao GUO Shu-hai LIU Guo-hua Qilian Alpine ecology and hydrology Research Station Key Laboratory of Ecohydrology of Inland River BasinNorthwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049 China

With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions may have different effects on the performance of the precipitation gauges, it is also necessary to test the gauges in different areas. This study mainly analyzed precipitation measurements from the single-Altershielded TRwS204 automatic weighing gauge(TRwS_(SA)) relative to the adjusted manual measurements(reference precipitation) from the Chinese standard precipitation gauge in a doublefence wind shield(CSPG_(DF)) in the Hulu watershed in the Qilian Mountains, China. The measurements were compared over the period from August 2014 to July2017, and the transfer function derived from the work by Kochendorfer et al.(2017 a) for correcting windinduced losses was applied to the TRwS_(SA) measurements. The results show that the average loss of TRwS_(SA) measurements relative to the reference precipitation decreased from 0.55 mm(10.7%) to 0.51 mm(9.9%) for rainfall events, from 0.35 mm(8.5%)to 0.22 mm(5.3%) for sleet events, and from 0.49 mm(18.9%) to 0.33 mm(12.7%) for snowfall events after adjustment. The uncorrected large biases of TRwS_(SA) measurements are considered to be mainly caused by specific errors of TRwS_(SA), different gauge orifice area and random errors. These types of errors must be considered when comparing precipitation measurements for different gauge types, especially in the mountains.

关键词：中国标准计量器降水调整区域测试气象站优先级分水岭

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ecology of industrial pollution in China

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Ecosystem Health and Sustainability 2020年第1期6卷 152-168,151页

作者： Jingjing Yuan Yonglong Lu Chenchen Wang Xianghui Cao Chunci Chen Haotian Cui Meng Zhang Cong Wang Xiaoqian Li Andrew C.Johnson Andrew J.Sweetman Di Du State Key Laboratory of Urban and Regional ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina Key Laboratory of the Ministry of Education for Coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityFujianChina University of Chinese Academy of Sciences BeijingChina Centre for ecology&hydrology OxonUK Lancaster Environment Centre Lancaster UniversityLancasterUK

Industrial development has brought China both opportunities and challenges since the reform and opening up in *** and temporal analysis showed that rapid industrialization has made eastern China under a more serious pollution *** most serious effects of industrial pollution were reflected in aquatic and soil ecosystem degradation,and damage can be observed from species,population,and community to ecosystem *** consciousness about contaminated sites rose from 2004 leading to greater efforts in ecological remediation,monitoring,and risk *** efforts are still needed in expanding the extent and breadth of monitoring to explore where the greatest ecological risks lie and how to control *** of industrial pollution has become a popular discipline in China and will be further developed to help achieve the Sustainable Development *** research for a better ecological risk management should be focused on multi-media transfer and effects of mixed pollutants,mechanisms for clean energy and material flow,and integration of ecological risk with human health risk.

关键词： Industrial pollution soil and aquatic ecosystem watershed monitoring and assessment contaminated site ecological risk assessment ecosystem management

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Climate change, water resources and sustainable development in the arid and semi-arid lands of Central Asia in the past 30 years

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Journal of Arid Land 2019年第1期11卷 1-14页

作者： YU Yang PI Yuanyue YU Xiang TA Zhijie SUN Lingxiao Markus DISSE ZENG Fanjiang LI Yaoming CHEN Xi YU Ruide Xinjiang Institute of ecology and Geography Chinese Academy of Sciences Research Center for ecology and Environment of Central Asia Chinese Academy of Sciences Cele National Station of Observation and Research for Desert-Grassland Ecosystem University of Chinese Academy of Sciences Chinese Academy of Forestry State Key Laboratory of Desert and Oasis ecology Chinese Academy of Sciences Chair of hydrology and River Basin Management Technical University of Munich School of Environment and Material Science Yantai University

The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the shrinkage of the Aral Sea, widespread desertification, soil salinization, biodiversity loss, frequent sand storms, and many other ecological disasters. This paper is a review article based upon the collection, identification and collation of previous studies of environmental changes and regional developments in Central Asia in the past 30 years. Most recent studies have reached a consensus that the temperature rise in Central Asia is occurring faster than the global average. This warming trend will not only result in a higher evaporation in the basin oases, but also to a significant retreat of glaciers in the mountainous areas. Water is the key to sustainable development in the arid and semi-arid regions in Central Asia. The uneven distribution, over consumption, and pollution of water resources in Central Asia have caused severe water supply problems, which have been affecting regional harmony and development for the past 30 years. The widespread and significant land use changes in the 1990 s could be used to improve our understanding of natural variability and human interaction in the region. There has been a positive trend of trans-border cooperation among the Central Asian countries in recent years. International attention has grown and research projects have been initiated to provide water and ecosystem protection in Central Asia. However, the agreements that have been reached might not be able to deliver practical action in time to prevent severe ecological disasters. Water management should be based on hydrographic borders and ministries should be able to make timely decisions without political intervention. Fully integrated management of water resources, land use and industrial development is essential in Central Asia. The ecological crisis should provide

关键词： Central Asia climate change water resources arid and semi-arid lands land use changes sustainable development socio-economic development

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Electromagnetic induction mapping at varied soil moisture reveals field-scale soil textural patterns and gravel lenses

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Frontiers of Agricultural Science and Engineering 2017年第2期4卷 135-145页

作者： Hiruy ABDU David A.ROBINSON Janis BOETTINGER Scott B.JONES Biological and Irrigation Engineering Department Utah State University Centre for ecology & hydrology Environment Centre Wales Plants Soils and Climate Department Utah State University

Knowledge of the spatial distribution of soil textural properties is important for determining soil moisture storage and soil hydraulic transport *** field heterogeneity without exhaustive sampling and costly sample analysis is difficult. Our objective was to employ electromagnetic induction(EMI) mapping in low apparent electrical conductivity(EC_a) soils at varying soil water contents to capture time invariant properties such as soil texture. Georeferenced EC_ameasurements were taken using a ground conductivity meter on six different days where volumetric water content(θ_v) varied from 0.11 to 0.23. The 50 m × 50 m field included a subsurface gravelly patch in an otherwise homogeneous silt-loam alluvial *** block kriging predicted EC_aat unsampled areas to produce 1-m resolution maps. Temporal stability analysis was used to divide the field into three distinct EC_a regions. Subsequent ground-truthing confirmed the lowest conductivity region correlated with coarse textured soil parent materials associated with a former high-energy alluvial depositional area. Combining maps using temporal stability analysis gives the clearest image of the textural difference. These maps could be informative for modeling,experimental design, sensor placement and targeted zone management strategies in soil science, ecology, hydrology,and agricultural applications.

关键词： soil electrical conductivity soil texture mapping temporal stability analysis

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Characteristics of runoff and sediment yield for two typical erodible soils in southern China

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International Journal of Sediment Research 2022年第5期37卷 653-661页

作者： Xuchao Zhu Yin Liang Lili Qu Longxi Cao Zhiyuan Tian Tong Liu Meng Li State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences College of Advanced Agricultural Sciences University of Chinese Academy of Sciences College of ecology and Environment Chengdu University of Technology National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of IntegratedAgro-environmental Pollution Control and Management Institute of Eco-environmental and Soil Sciences Guangdong Academy of Sciences hydrology and Water Resources Investigation Bureau of Jiangsu Province

Granite red soil(GRS) and Quaternary red clay(QRC) are two typical erodible soils in the red-soil region of southern China. Analytical and comparative studies of the characteristics of runoff and sediment yield for the two soils at various slopes are currently needed. The purpose of the current study was to clarify the characteristics of runoff and sediment yield for GRS and QRC at different slopes and to establish models for estimating sediment yield for the two soils. Forty-eight runoff microplots with four slopes(5°, 15°, 25°, and 35°) and two soils(GRS and QRC) were established and exposed to natural rainfall. Runoff and sediment yield were measured 10 times during the study period. Runoff and sediment yield for the two soils under the various slopes had similar temporal variations, and both increased with prior cumulative erosive rainfall. Runoff for GRS and QRC was moderately temporally variable, with coefficients of variation(CVs) from 46.2% to 60.6%, and sediment yield for QRC was strongly temporally variable, with CVs from 114.8% to 145.8%. Sediment yield for GRS increased with slope, but sediment yield for QRC first increased and then decreased, with a calculated inflection point of 18°, but runoff for both soils decreased with slope. The CVs of both runoff and sediment yield with slope for the two soils ranged from 3.6% to 88.0%, lower than the temporal variabilities, indicating that rainfall may have a larger impact than slope on runoff and sediment yield for QRC and GRS. Under the various slopes, runoff and sediment yield for both soils increased with rainfall and sediment yield increased with runoff, but the proportions of effective rainfall and runoff differed. Pedotransfer-function models based on rainfall, runoff, and slope accurately estimated sediment yield for the two soils, with the model fit coefficient of determination(R2) > 0.81 and the R2for verification >0.79. These results improve the understanding of the laws governing erosion for differe

关键词： Runoff and sediment characteristics Sediment-yield simulation Granite red soil Quaternary red clay Pedotransfer function Red-soil region

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