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Remote estimates of suspended particulate matter in global lakes using machine learning models

International Soil and Water Conservation Research 2024年第1期12卷 200-216页

作者： Zhidan Wen Qiang Wang Yue Ma Pierre Andre Jacinthe Ge Liu Sijia Li Yingxin Shang Hui Tao Chong Fang Lili Lyu Baohua Zhang kaishan Song Northeast Institute of Geography and Agroecology CASChangchunJilin130102China Department of Geology Indiana University∼Purdue UniversityIndianapolisIN44602USA University of Chinese Academy of Sciences Beijing100100China College of Geography and Urban Planning Liaocheng UniversityLiaochengChina

Suspended particulate matter(SPM)in lakes exerts strong impact on light propagation,aquatic ecosystem productivity,which co-varies with nutrients,heavy metal and micro-pollutant in *** lakes,SPM exerts strong absorption and backscattering,ultimately affects water leaving signals that can be detected by satellite *** regression models based on specific band or hand ratios have been widely used for SPM estimate in the past with moderate *** are still rooms for model accuracy improvements,and machine learning models may solve the non-linear relationships between spectral variable and SPM in *** assembled more than 16,400 in situ measured SPM in lakes from six continents(excluding the Antarctica continent),of which 9640 samples were matched with Landsat overpasses within±7 *** machine learning algorithms and two simple regression methods(linear and partial least squares models)were used to estimate SPM in lakes and the performance were *** overcome the problem of imbalance datasets in regression,a Synthetic Minority Over-Sampling technique for regression with Gaussian Noise(SMOGN)was adopted in this *** comparison,we found that gradient boosting decision tree(GBDT),random forest(RF),and extreme gradient boosting(XGBoost)models demonstrated good spatiotemporal transferability with SMOGN processed dataset,and has potential to map SPM at different year with good quality of Landsat land surface reflectance *** all the tested modeling approaches,the GBDT model has accurate calibration(n=6428,R^(2)=0.95,MAPE=29.8%)from SPM collected in 2235 lakes across the world,and the validation(n=3214,R^(2)=0.84,MAPE=38.8%)also exhibited stable ***,the good performances were also exhibited by RF model with calibration(R^(2)=0.93)and validation(R^(2)=0.86,MAPE=24.2%)*** applied GBDT and RF models to map SPM of typical lakes,and satisfactory result was *** addition,the GBDT model was evaluated b

关键词： Landsat imagery Remote estimation SPM Transferability

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基于Sentinel-2影像东北秋季典型湖泊大气校正方法适用性评价

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地理科学 2024年第1期44卷 149-158页

作者：李勇李思佳宋开山徐茂林刘阁辽宁科技大学土木工程学院辽宁鞍山114000 中国科学院东北地理与农业生态研究所吉林长春130102

本文利用6S(Second Simulation of a Satellite Signal in the Solar Spectrum)、Acolite DSF(Dark spectrum fitting)、C2RCC(Case 2 Regional Coast Color)、SeaDas(SeaWiFS Data Analysis System)、Sen2Cor(Sentinel 2 Correction)、Polymer(Polynomial based algorithm applied to MERIS)和iCOR(Image correction for atmospheric effects)7种大气校正算法,结合松花湖、月亮泡、小兴凯湖实测遥感反射率数据对“哨兵-2号”(Sentinel-2)数据进行大气校正研究,验证算法性能。整体校正结果显示,相较于实测遥感反射率,上述7种大气校正算法均在可见光波段(400~800 nm)呈现不同程度的低估。除C2RCC算法外,其余6种算法校正后的遥感反射率与实测光谱曲线变化趋势基本吻合,其中Sen2Cor算法与iCOR算法性能最佳,Polymer算法性能最差;在单波段校正精度对比中,Sen2Cor和iCOR算法几乎所有波段的均方根误差和平均绝对百分比误差都低于其余5种算法。Sen2Cor算法在560 nm、665 nm和705 nm处校正精度优于其余6种算法,iCOR算法在443 nm和740 nm处有良好的表现,在490 nm处6S算法校正精度最高,拥有最低的均方根误差(0.0059 sr^(−1))和平均绝对百分比误差(21.40%)。结果表明,这7种大气校正算法均可以在一定程度上去除大气影响,增加影像的可用性,Sen2Cor算法和iCOR算法更适用于本文所研究水体或相似水体。

关键词：大气校正 Sentinel-2卫星内陆湖泊水体遥感反射率

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大鼠原位肝移植解剖重建研究进展

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器官移植 2024年第3期15卷 469-473页

作者：吴伟康李霄王旭丹丁睿陶开山空军军医大学西京医院肝胆胰脾外科西安710032

大鼠肝移植模型的构建,为解决临床肝移植术后并发症及围手术期治疗等问题提供了理想的动物模型。随着对大鼠肝移植模型建立的深入研究,逐渐形成了经典的“二袖套”法。然而,在移植手术过程中,手术视野差、血管扭转、胆道损伤和无肝期较... 详细信息

大鼠肝移植模型的构建,为解决临床肝移植术后并发症及围手术期治疗等问题提供了理想的动物模型。随着对大鼠肝移植模型建立的深入研究,逐渐形成了经典的“二袖套”法。然而,在移植手术过程中,手术视野差、血管扭转、胆道损伤和无肝期较长等问题仍是传统方法无法避免的。目前国内外大鼠肝移植模型改进方式主要围绕肝上下腔静脉、门静脉、肝下下腔静脉和胆管这4个重要解剖结构的重建展开。为此,本文就肝上下腔静脉、门静脉、肝下下腔静脉和胆管重建领域的最新进展进行整理总结,以便为大鼠肝移植模型的构建提供参考,促进肝移植技术的进一步发展。

关键词：原位肝移植大鼠血管吻合磁环吻合肝上下腔静脉门静脉肝下下腔静脉胆管

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外膜囊泡的物质传递及细菌保护作用研究进展

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微生物学报 2024年第2期64卷 364-377页

作者：潘琪琪王涓汪智肖铠姗吴清平广东省科学院微生物研究所、国家卫健委微生物食品营养与安全科技创新平台、华南应用微生物国家重点实验室、广东省微生物安全与健康重点实验室广东广州510070 华南农业大学食品学院广东广州510642

外膜囊泡(outer membrane vesicles,OMVs)是一种直径为10-250 nm的球状结构,由革兰氏阴性菌分泌。OMVs已逐渐被认为是一种新型的分泌系统,它能运输脂质、蛋白质、核酸、细胞毒素和信号分子等不同物质,具有多种生物学功能,包括细菌与细... 详细信息

外膜囊泡(outer membrane vesicles,OMVs)是一种直径为10-250 nm的球状结构,由革兰氏阴性菌分泌。OMVs已逐渐被认为是一种新型的分泌系统,它能运输脂质、蛋白质、核酸、细胞毒素和信号分子等不同物质,具有多种生物学功能,包括细菌与细菌之间的交流、致病因子传递、抵抗外界不良环境和调节免疫反应等。近年来,细菌OMVs基于生物特征介导的抗生素耐药性传递与OMVs的应用潜能逐步受到重视。本文旨在对细菌OMVs的来源与物质传递作用、其在抗生素条件与其他逆境环境下的细菌保护作用、细菌OMVs在治疗疾病方面的应用潜力进行综述,以期对OMVs的相关研究提供更全面的认识。

关键词：外膜囊泡耐药性物质传递保护应用

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Validation of Global Evapotranspiration Product(MOD16) Using Flux Tower Data from Panjin Coastal Wetland,Northeast China

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Chinese Geographical Science 2018年第3期28卷 420-429页

作者： DU Jia SONG kaishan Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Recent advances in remote sensing technology and methods have resulted in the development of an evapotranspiration(ET) product from the Moderate Resolution Imaging Spectrometer(MOD16). The accuracy of this product however has not been tested for coastal wetland ecosystems. The objective of this study therefore is to validate the MOD16 ET product using data from one eddy covariance flux tower situated in the Panjin coastal wetland ecosystem within the Liaohe River Delta, Northeast China. Cumulative ET data over an eight-day period in 2005 from the flux tower was calculated to coincide with the MOD16 products across the same period. Results showed that data from the flux tower were inconsistent with that gained form the MOD16 ET. In general, results from Panjin showed that there was an underestimation of MOD16 ET in the spring and fall, with Biases of -2.27 and -3.53 mm/8 d, respectively(–40.58% and -49.13% of the observed mean). Results for Bias during the summer had a range of 1.77 mm/8 d(7.82% of the observed mean), indicating an overestimation of MOD16 ET. According to the RMSE, summer(6.14 mm/8 d) achieved the lowest value, indicating low accuracy of the MOD16 ET product. However, RMSE(2.09 mm/8 d) in spring was the same as that in the fall. Relationship between ET and its relevant meteorological parameters were analyzed. Results indicated a very good relationship between surface air temperature and ET. Meanwhile a significant relationship between wind speed and ET also existed. The inconsistent comparison of MOD16 and flux tower-based ET are mainly attributed to the parameterization of the Penman-Monteith model, flux tower measurement errors, and flux tower footprint vs. MODIS pixels.

关键词： Moderate Resolution Imaging Spectrometer(MODIS) MOD16 evapotranspiration validation coastal wetland eddy covariance flux tower

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Tailpipe emission characterizations of diesel-fueled forklifts under real-world operations using a portable emission measurement system

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Journal of Environmental Sciences 2021年第2期33卷 34-42页

作者： Kaili Pang kaishan Zhang Shuai Ma Department of Environm ental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

Non-road equipment is one of the key contributing sources to air ***,an accurate development of emission inventory from non-road equipment is imperative for air quality management,especially for equipment with a large population such as diesel-fueled *** objective of this paper is to characterize duty-cycle based emissions from diesel-fueled forklifts using a portable emission measurement system(PEMS).Three dutycycles were defined in this study,including idling,moving,and working(active duty operation)and used to characterize in-use emissions for diesel-fueled forklifts.A total of twelve diesel-fueled forklifts were selected for real-world emission *** showed that fuel-based emission factors appear to have smaller variability compared to time-based *** example,the time-based emission factors for CO,HC,NO,and PM 2.5 for forklifts were estimated to be 16.6-43.9,5.3-15.1,26.2-49.9,5.5-11.1 g/hr with the fuel-based emission factors being 12.1-20.3,4.1-8.3,19.1-32.4,3.5-6.5 g/kg-fuel,*** emissions appear to be the biggest concern for emissions ***,most of the emissions factors estimated from this study are significantly different from those in both National Guideline for Emission Inventory Development for Non-Road Equipment in China and welldeveloped emission factor models such as NONROAD by US *** implies that localized,preferably fuel-based emission factors should be adjusted based on real-world emission measurements in order to develop a representative emission inventory for non-road equipment.

关键词： Non-road equipment Forklifts Portable emission measurement system(pems) Emission factors Emission inventory

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5株外源嗜热固氮菌对堆肥碳氮损失及其细菌群落的影响

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甘肃农业大学学报 2024年第4期59卷 225-235页

作者：杨迎香张文明陈开山邢彦宏甘肃农业大学资源与环境学院甘肃兰州730070

【目的】减少堆肥过程中碳氮损失,提高堆肥质量。【方法】本研究通过添加5株外源嗜热固氮菌株,设置6个处理分别为:CK(不添加外源固氮菌)、A1(根癌异根瘤菌)、A2(亮杆菌)、A3(头状葡萄菌)、B1(液化沙雷菌)和B2(蜡样芽孢杆菌)进行堆肥,研... 详细信息

【目的】减少堆肥过程中碳氮损失,提高堆肥质量。【方法】本研究通过添加5株外源嗜热固氮菌株,设置6个处理分别为:CK(不添加外源固氮菌)、A1(根癌异根瘤菌)、A2(亮杆菌)、A3(头状葡萄菌)、B1(液化沙雷菌)和B2(蜡样芽孢杆菌)进行堆肥,研究外源嗜热固氮菌对堆肥碳氮损失、养分含量和细菌微生物群落的影响。【结果】5株外源嗜热固氮菌均减少了堆肥中碳氮损失,提高了养分含量。A1、A2、A3、B1、B2与CK相比碳氮损失分别减少了38.74%、26.99%、33.09%、28.75%、34.35%和25.23%、11.20%、22.58%、20.77%、20.51%,氮含量增加了279.15%、42.74%、344.31%、277.51%、1.42%;磷含量增加了49.21%、16.19%、51.33%、24.26%、58.90%;全钾含量增加了27.76%、17.41%、16.35%、11.80%、29.12%;有机质增加了31.41%、20.56%、27.15%、30.19%、26.61%,总体上A1>A3>B1>A2>B2。细菌群落结构演替表明,A1和B1菌株的丰度在堆肥过程中始终高于对照处理。外源固氮菌均显著提高了堆肥中土著固氮细菌Pseudomonas(假单胞菌属),Sphingobacterium(鞘氨醇杆菌属)、Saccharomonospora(糖单孢菌属)、Planifilum(直丝菌属)和Bacillus(芽孢杆菌属)等的相对丰度,降低具有反硝化能力的Acinetobacter(不动杆菌属)、Corynebacterium(棒状杆菌属)和Halomonas(盐单胞菌属)等的丰度。KEGG分析表明,外源固氮菌剂影响氨基酸代谢、碳水化合物代谢和次生代谢产物的生物合成功能基因。【结论】A1和B1菌株能够较好地在堆肥中定殖,具有开发固氮菌生物有机肥的潜力;添加外源固氮菌均可通过影响优势微生物群落及氨基酸代谢、碳水化合物代谢等功能基因抑制堆肥过程中的碳氮代谢,提高养分含量,减少堆肥过程中碳氮损失。

关键词：堆肥外源嗜热固氮菌碳氮损失细菌群落

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补灌条件下施磷量对小麦不同茎蘖^(13)C同化物分配及其成穗的影响

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应用生态学报 2024年第4期35卷 942-950页

作者：惠凯善冉庆赏石玉张振于振文张永丽山东农业大学农学院/小麦育种全国重点实验室/农业农村部作物生理生态与耕作重点实验室山东泰安271018

为明确补灌条件下促进小麦分蘖发生成穗和磷肥高效利用的适宜施磷量及其生理机制,以‘济麦22’小麦品种为供试材料,设置低磷(90 kg P_(2)O_(5)·hm^(-2),P_(1))、中磷(135 kg P_(2)O_(5)·hm^(-2),P_(2))和高磷(180 kg P_(2)O_(5)·hm^(... 详细信息

为明确补灌条件下促进小麦分蘖发生成穗和磷肥高效利用的适宜施磷量及其生理机制,以‘济麦22’小麦品种为供试材料,设置低磷(90 kg P_(2)O_(5)·hm^(-2),P_(1))、中磷(135 kg P_(2)O_(5)·hm^(-2),P_(2))和高磷(180 kg P_(2)O_(5)·hm^(-2),P_(3))处理,以不施磷为对照(P_(0)),各处理拔节期和开花期土壤相对含水量均补灌至70%,测定了小麦分蘖节面积和内源激素含量、各蘖位分蘖发生数、光合参数、^(13)C同化物在各茎蘖的分配、籽粒产量及磷肥偏生产力。结果表明:与P_(0)和P_(1)相比,P_(2)显著提高了小麦分蘖节面积、反式玉米素(tZ)含量、主茎最上部展开叶光合参数、单株总茎蘖数和^(13)C同化物在各茎蘖的分配量,单株成穗数分别增加0.51和0.36个,籽粒产量分别增加40.3%和13.2%;P3处理下,小麦分蘖数增加,但单株成穗数减少,籽粒产量和磷肥偏生产力降低。中磷处理(135 kg·hm^(-2))为本试验补灌条件下小麦高产高效的适宜磷肥用量。

关键词：小麦施磷量分蘖成穗籽粒产量磷肥偏生产力

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Quantification of emission variability for off-road equipment in China based on real-world measurements

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Frontiers of Environmental Science & Engineering 2022年第2期16卷 125-136页

作者： Kaili Pang kaishan Zhang Shuai Ma Xiangrui Meng Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

The objective of this paper is to quantify the variability in emissions of off-road equipment using a portable emission measurement system.A total of 53 commonly used equipment for agriculture,base construction,paving construction,and material handling were ***-based and fuel-based emissions were quantified by different duty and engine *** duty modes(idling,moving,and working)were *** engine modes were defined based on normalized engine revolutions-per-minute and manifold absolute pressure,*** emission factors taking into account both duty modes and its corresponding time percentage during a typical duty cycle were *** showed that there existed a large off-road equipment variability in *** on duty and engine modes,time-based NO emissions ranged from 3.1 to 237.9,29.1‒1475.6,83.2‒681.6,and 3.2‒385.2 g/h for agriculture,base construction,paving construction and material handling equipment,respectively while for fuel-based NO emissions these ranges were 5.3‒52.0,11.7‒69.0,4.8‒30.8,and 11.0‒54.6 g/kg,***,emission factors derived from this study exhibited a much larger variability compared to those used in NONROAD by US EPA and National Guideline for Off-road Equipment of *** implied that localized measurements of emissions are needed for improvement of accuracy of emission ***,both equipment types and operations should be considered for development of emission inventory and control strategy.

关键词： Off-road equipment Portable emission measurement system(PEMS) Real-world emissions Diesel engine

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Impact of the Zhalong Wetland on Neighboring Land Surface Temperature Based on Remote Sensing and GIS

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Chinese Geographical Science 2019年第5期29卷 798-808页

作者： DU Jia SONG kaishan YAN Baohua Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130102China Jilin Natural ResourcesInvestigation and Planning Center Co. LtdChangchun130061China

Wetlands play a key role in regulating local climate as well as reducing impacts caused by climate change. Rapid observations of the land surface temperature(LST) are, therefore, valuable for studying the dynamics of wetland systems. With the development of thermal remote sensing technology, LST retrieval with satellite images is a practicable way to detect a wetland and its neighboring area’s thermal environment from a non-point visual angle rather than the traditional detection from a point visual angle. The mono-windows(MW) method of retrieving LST was validated. On the basis of estimated LST, we used Geographical Information System(GIS) technology to study the impact of wetland reclamation on local temperatures at a regional scale. Following that, correlations between LST and the wetland were analyzed. The results show that: 1) It is feasible to retrieve the LST from Landsat 8 OLI satellite images with MW model. The model was validated with the land surface temperature observed in four meteorological stations when the satellite scanned the study region. The satellite retrieval error was approximately 1.01°C. 2) The relationship between the spatial distribution of land surface temperatures and the Zhalong wetland was analyzed based on GIS technology. The results show that wetland has an obvious influence on LST, and that this influence decreases with increasing distance from the wetland. When the distance from the wetland was less than 500 m, its influence on LST was significant. Results also illustrated that the effect of the wetland’s different land use/land cover’s LST distribution varied with different seasons.

关键词： land surface temperature cold-humid effect influence distance Zhalong wetland

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