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Evaluation of Port Prosperity Based on High Spatial Resolution Satellite Remote Sensing Images 认领
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作者 SUO Anning XU Jingping +1 位作者 LI Xuchun WEI Baoquan 《中国地理科学:英文版》 SCIE CSCD 2020年第5期889-899,共11页
More and more ports appeared along China’s coastline, which destroyed natural coastline and coastal landscape. Some of them are inefficiency operations. It is important to evaluate operational efficiency of ports to ... More and more ports appeared along China’s coastline, which destroyed natural coastline and coastal landscape. Some of them are inefficiency operations. It is important to evaluate operational efficiency of ports to reveal their position in regional competitive environment. In this study, high spatial resolution satellite remote sensing images were used to monitor ship number and plane area. The port-use prosperity index(PUI) was subsequently proposed to quantitatively describe port-use business and reveal port-use efficiency. The PUI was applied to six ports around the Bohai Sea, China. The number, scale, and plane of ships docked in these ports were easily monitored by the high spatial resolution satellite remote sensing images, and the PUI was calculated using a ship’s total plane area and length of docked coastline. The PUI is an objective and practical index for evaluating port-use efficiency. It can be used to compare differences in port use and indicate temporal port-use dynamics. The PUI values of Jingtang and Tianjin Ports were the highest(17.75 and 14.14, respectively), whereas that of Yantai Port was the lowest(8.31). The PUI values of the remaining ports were 9.0–10.70. A linear relationship existed between port throughput and PUI in the studied ports. This can forecast port throughput by monitoring and calculating PUI based on high spatial resolution satellite remote sensing images. 展开更多
关键词 port-use prosperity index(PUI) ship number plane area port-use efficiency the Bohai Sea
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中国节约利用油气资源的必要性与方法探讨 认领
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作者 吴建邦 杨胜来 《科学技术与工程》 北大核心 2020年第11期4191-4201,共11页
分析中国油气资源利用现状,根据中国能源禀赋与供需矛盾提出节约合理利用的油气资源利用思路,根据中国油气消费结构提出"节约用油,合理用气"的油气资源利用方向和"交通节油、工业节油"的节油重点方向,进而提出了具... 分析中国油气资源利用现状,根据中国能源禀赋与供需矛盾提出节约合理利用的油气资源利用思路,根据中国油气消费结构提出"节约用油,合理用气"的油气资源利用方向和"交通节油、工业节油"的节油重点方向,进而提出了具有针对性的节油用气的方法。统计分析表明,中国能源效率相对低下,但节油潜力巨大,应尽快调整经济产业结构,推广节能技术,加强政策综合调控,构建资源节约型社会,提高油气利用效率,促进形成高效、清洁、低碳的能源结构,从而更好地实现中国经济社会的可持续发展。 展开更多
关键词 油气资源 节约利用 合理利用 能源效率
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Canopy morphological changes and water use efficiency in winter wheat under different irrigation treatments 认领
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作者 ZHAO Hong-xiang ZHANG Ping +3 位作者 WANG Yuan-yuan NING Tang-yuan XU Cai-long WANG Pu 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第4期1105-1116,共12页
Water is a key limiting factor in agriculture. Water resource shortages have become a serious threat to global food security. The development of water-saving irrigation techniques based on crop requirements is an impo... Water is a key limiting factor in agriculture. Water resource shortages have become a serious threat to global food security. The development of water-saving irrigation techniques based on crop requirements is an important strategy to resolve water scarcity in arid and semi-arid regions. In this study, field experiments with winter wheat were performed at Wuqiao Experiment Station, China Agricultural University in two growing seasons in 2013-2015 to help develop such techniques. Three irrigation treatments were tested: no-irrigation(i.e., no water applied after sowing), limited-irrigation(i.e., 60 mm of water applied at jointing), and sufficient-irrigation(i.e., a total of 180 mm of water applied with 60 mm at turning green, jointing and anthesis stages, respectively). Leaf area index(LAI), light transmittance(LT), leaf angle(LA), transpiration rate(Tr), specific leaf weight, water use efficiency(WUE), and grain yield of winter wheat were measured. The highest WUE of wheat in the irrigated treatments was found under limited-irrigation and grain yield was only reduced by a small amount in this treatment compared to the sufficient irrigation treatment. The LAI and LA of wheat plants was lower under limited irrigation than sufficient irrigation, but canopy LT was greater. Moreover, the specific leaf weight of winter wheat was significantly lower under sufficient than limited irrigation conditions, while the leaf Tr was significantly higher. Correlation analysis showed that the increased LAI was associated with an increase in the leaf Tr, but the specific leaf weight had the opposite relationship with transpiration. Optimum WUE occurred over a reasonable range in leaf Tr. In conclusion, reduced irrigation can optimize wheat canopies and regulate water consumption, with only small reductions in final yield, ultimately leading to higher wheat WUE and water saving in arid and semi-arid regions. 展开更多
关键词 winter wheat limited-irrigation CANOPY characteristics TRANSPIRATION rate water use efficiency
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Tolerance to low phosphorus in rice varieties is conferred by regulation of root growth 认领
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作者 Yaping Deng Chuanbao Men +7 位作者 Shengfeng Qiao Wenjie Wang Junfei Gu Lijun Liu Zujian Zhang Hao Zhang Zhiqin Wang Jianchang Yang 《作物学报:英文版》 SCIE CAS CSCD 2020年第4期534-547,共14页
Phosphorus use efficiency(PUE)can be improved through cultivation techniques and breeding.However,little is known about rice(Oryza sativa L.)agronomic and physiological traits associated with high PUE.We characterized... Phosphorus use efficiency(PUE)can be improved through cultivation techniques and breeding.However,little is known about rice(Oryza sativa L.)agronomic and physiological traits associated with high PUE.We characterized the agronomic and physiological traits of rice varieties with different tolerances to low phosphorus in nutrient solution.Two varieties with strong tolerance to low phosphorus(STVs)and two with weak tolerance(WTVs)were grown at normal(NP,control)and low phosphorus(LP,1/20 of NP)concentrations.Plants grown at LP produced significantly lower grain yield than those grown at NP.WTVs yields were lower than STVs yields.Compared to NP,LP significantly increased phosphorus translocation efficiency(PTE),internal phosphorus efficiency(IPE)and phosphorus harvest index(PHI).Under the LP condition,PTE and IPE were higher for STVs than for WTVs.LP also reduced tiller number,shoot biomass,leaf area index(LAI),leaf photosynthetic rate,and mean root diameter of both kinds of varieties at the main growth stages,but to a lower extent in STVs.LP significantly increased the number of productive tillers,root biomass,root-shoot ratio,root bleeding rate,and root acid phosphatase(RAP)activity.Total root length,root oxidation activity(ROA),and root total and active absorbing surface areas for STVs were significantly increased under LP,whereas the opposite responses were observed for WTVs.Total root length,ROA,root bleeding rate,root active absorbing surface area,and RAP activity were positively and significantly correlated with grain yield,PTE,and IPE.These results suggest that the tolerance of rice varieties to a low-phosphorus growth condition is closely associated with root growth with higher biomass and activity. 展开更多
关键词 Rice(Oryza sativa L.) TOLERANCE Phosphorus use efficiency Root traits
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智能控制在矿山机电一体化系统中的应用 认领
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作者 韦海 《河南科技》 2020年第8期73-75,共3页
机电设备是矿山企业的核心设备,广泛应用于各类矿山工程中。传统的矿山机电设备控制难度较大,往往需要花费较多的人力,使得矿山工程开采成本上升。智能化时代,各类矿山工程开始引进和运用机电一体化系统,而智能控制技术可以提升设备的... 机电设备是矿山企业的核心设备,广泛应用于各类矿山工程中。传统的矿山机电设备控制难度较大,往往需要花费较多的人力,使得矿山工程开采成本上升。智能化时代,各类矿山工程开始引进和运用机电一体化系统,而智能控制技术可以提升设备的智能化控制水平和协同工作效果。因此,本文分析了常见的智能控制系统,探究了智能控制在矿山机电一体化系统中的具体应用,以期提升我国矿山工程生产效率和安全水平。 展开更多
关键词 智能控制 机电一体化系统 矿山工程 设备寿命 使用效率
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Effect of calcium silicate on nutrient use of lowland rice and greenhouse gas emission from a paddy soil under alternating wetting and drying 认领
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作者 Hyun-Hwoi KU Keiichi HAYASHI +1 位作者 Ruth AGBISIT Gina VILLEGAS-PANGGA 《土壤圈:英文版》 SCIE CAS CSCD 2020年第4期535-543,共9页
In intensively irrigated rice cultivation,plant-available silicon(Si)is a crucial nutrient for improving rice productivity.As a source of Si,calcium silicate(CaSiO3)was amended to evaluate the effect of silicate ferti... In intensively irrigated rice cultivation,plant-available silicon(Si)is a crucial nutrient for improving rice productivity.As a source of Si,calcium silicate(CaSiO3)was amended to evaluate the effect of silicate fertilizer on rice production,nitrogen(N)use efficiency,and greenhouse gas(GHG)emission under alternating wetting and drying in a pot experiment using a tropical soil from a paddy field of the International Rice Research Institute(IRRI)in the Philippines.Four levels of CaSiO3 amendment,0,112.7,224.5,and 445.8 kg ha^-1,with the recommended N rate were tested.The results showed that although CaSiO3amendment of 112.7 kg ha^-1resulted in higher rice straw,improved N use efficiency,and reduced N2O emission,there was no difference in grain yield among the four levels of CaSiO3 amendment owing to relatively lower harvest index.Moreover,CaSiO3 amendment showed a reverse trend between CH4 and N2O emissions as it reduced N2O emission while led to significantly increased CH4 emission and global warming potential.Thus,CaSiO3 amendment was a possible alternative to improve N use efficiency and increase rice straw biomass,but it needs to be reviewed in line with grain yield production and GHG emission.It is also imperative to test an optimal method of silicate fertilizer amendment in future research in order to compromise a negative impact in tropical soils. 展开更多
关键词 CH4 emission N use efficiency N2O emission plant-available Si rice straw biomass silicate fertilizer tropical soil
Plant abiotic stress response and nutrient use efficiency 认领
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作者 Zhizhong Gong Liming Xiong +14 位作者 Huazhong Shi Shuhua Yang Luis R.Herrera-Estrella Guohua Xu Dai-Yin Chao Jingrui Li Peng-Yun Wang Feng Qin Jigang Li Yanglin Ding Yiting Shi Yu Wang Yongqing Yang Yan Guo Jian-Kang Zhu 《中国科学:生命科学英文版》 SCIE CAS CSCD 2020年第5期635-674,共40页
Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit th... Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies. 展开更多
关键词 abiotic stress sensing nutrient use efficiency heavy metal Ca2+signaling ROS signal transduction PHOSPHORYLATION transcription factor TRANSPORTER
Responses of water use efficiency to phenology in typical subtropical forest ecosystems--A case study in Zhejiang Province 认领
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作者 Fengsheng GUO Jiaxin JIN +2 位作者 Bin YONG Ying WANG Hong JIANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第1期145-156,共12页
Ecosystem-scale water-use efficiency(WUE) is an important indicator for understanding the intimately coupled relationship between carbon and water cycles in ecosystems. Previous studies have suggested that both abioti... Ecosystem-scale water-use efficiency(WUE) is an important indicator for understanding the intimately coupled relationship between carbon and water cycles in ecosystems. Previous studies have suggested that both abiotic and biotic factors have significant effects on WUE in forest ecosystems. However, responses of WUE to phenology in the context of climate change remain poorly understood. In this study, we analyzed the sensitivity and response patterns of seasonal WUE to phenology in Zhejiang Province where typical subtropical forest ecosystems are located, and discussed potential causes of the changes of the sensitivity and response patterns along different climate gradient during 2000–2014. The results of interannual partial correlation analysis showed widespread negative correlations between WUE and the start of growing season(SOS) in spring. This is because the increase in gross primary product(GPP) is larger than that of evapotranspiration(ET), resulting from an advanced SOS. The positive correlation between WUE and SOS was widely observed in summer mainly because of water stress and plant ecological strategy. The autumn WUE enhanced with the delay in the end of growing season(EOS)mainly because of the increase in GPP meanwhile the decrease or steadiness in ET, resulting from a delayed EOS. In space, the sensitivity of spring WUE to SOS significantly decreased along the radiation gradient, which might be related to strong soil evaporation in high radiation area;the sensitivity of WUE to SOS in summer showed a positive correlation with precipitation and a negative correlation with temperature, respectively, which might be attributed to the compensation of GPP to the delayed SOS and water stress caused by high temperature. The sensitivity of WUE to EOS increased significantly along the radiation and precipitation gradients in autumn, which may be because the increase of radiation and precipitation provides more water and energy for photosynthesis. 展开更多
关键词 WATER-USE efficiency GROSS primary product EVAPOTRANSPIRATION PHENOLOGY Climate gradient Forest
Effects of Combined Organic-inorganic Fertilization on Quality and Water Use Efficiency of Spring Maize under Equal Nitrogen Fertilization 认领
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作者 Defeng WU 《亚洲农业研究:英文版》 2020年第5期42-46,共5页
The experiment was conducted in the abandoned land of Liangjia Village,Huayin City,Shaanxi Province from April to September 2019.The experimental crop was spring maize.A total of six treatments were set up in a random... The experiment was conducted in the abandoned land of Liangjia Village,Huayin City,Shaanxi Province from April to September 2019.The experimental crop was spring maize.A total of six treatments were set up in a randomized block design.The moisture content of the top 0-60 cm soil was determined regularly,and the yield and quality indices of maize at maturity were checked.The results show that:(i)combined organic-inorganic fertilization increased the yield of spring maize by 3%-8%.(ii)Compared with CK,fertilization treatments significantly improved the water use efficiency of spring maize,with an increase of 59.2%.The average water use efficiency of three combined organic-inorganic fertilization treatments was 27.81 kg/(ha·mm).Compared with CON,combined application of organic and inorganic fertilizers significantly improved the water use efficiency of spring maize,with an increase of 12.5%.(iii)The combined application of organic and inorganic fertilizers increased the moisture,total starch,crude protein and crude fat contents,and reduced crude fiber content of maize kernels.However,with the increase of the proportion of organic fertilizer,the crude protein content of maize kernels decreased.(iv)Yield of spring maize showed a significant parabolic relationship with soil water consumption.In summary,70%inorganic fertilizer+30%organic fertilizer is a scientific and reasonable way of fertilization. 展开更多
关键词 Equal nitrogen fertilization Combined organic-inorganic fertilization MAIZE QUALITY Water use efficiency
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Mitigating N2O and NO Emissions from Direct-Seeded Rice with Nitrification Inhibitor and Urea Deep Placement 认领
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作者 Yam Kanta Gaihre Upendra Singh +2 位作者 Wendie DBible Job Fugice Jr Joaquin Sanabria 《水稻科学:英文版》 SCIE CSCD 2020年第5期434-444,共11页
Soil-emitted nitrous oxide(N2O) and nitric oxide(NO) in crop production are harmful nitrogen(N) emissions that may contribute both directly and indirectly to global warming. Application of nitrification inhibitors, su... Soil-emitted nitrous oxide(N2O) and nitric oxide(NO) in crop production are harmful nitrogen(N) emissions that may contribute both directly and indirectly to global warming. Application of nitrification inhibitors, such as dicyandiamide(DCD), and urea deep placement(UDP), are considered effective approaches to reduce these emissions. This study investigated the effects of DCD and UDP, compared to urea and potassium nitrate, on emissions, nitrogen use efficiency and grain yields under direct-seeded rice. High-frequency measurements of N2O and NO emissions were conducted using the automated closed chamber method throughout the crop-growing season and during the ratoon crop. Both UDP and DCD were effective in reducing N2O emissions by 95% and 73%, respectively. The highest emission factor(1.53% of applied N) was observed in urea, while the lowest was in UDP(0.08%). Emission peaks were mainly associated with fertilization events and appeared within one to two weeks of fertilization. Those emission peaks contributed to 65%–98% of the total seasonal emissions. Residual effects of fertilizer treatments on the N2O emissions from the ratoon crop were not significant;however, the urea treatment contributed 2%, whereas UDP contributed to 44% of the total annual emissions. On the other hand, cumulative NO emissions were not significant in either the rice or ratoon crops. UDP and DCD increased grain yields by 16%–19% and N recovery efficiency by 30%–40% over urea. The results suggested that the use of DCD and UDP could mitigate N2O emissions and increase grain yields and nitrogen use efficiency under direct-seeded rice condition. 展开更多
关键词 DICYANDIAMIDE direct-seeded rice nitric oxide nitrification inhibitor nitrogen use efficiency nitrous oxide urea deep placement
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Effects of water application uniformity using a center pivot on winter wheat yield, water and nitrogen use efficiency in the North China Plain 认领
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作者 CAI Dong-yu YAN Hai-jun LI Lian-hao 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第9期2326-2339,共14页
In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the gr... In recent years, the use of fertigation technology with center pivot irrigation systems has increased rapidly in the North China Plain (NCP). The combined effects of water and nitrogen application uniformity on the grain yield, water use efficiency (WUE) and nitrogen use efficiency (NUE) have become a research hotspot. In this study, a two-year field experiment was conducted during the winter wheat growing season in 2016–2018 to evaluate the water application uniformity of a center pivot with two low pressure sprinklers (the R3000 sprinklers were installed in the first span, the corresponding treatment was RS;the D3000 sprinklers were installed in the second span, the corresponding treatment was DS) and a P85A impact sprinkler as the end gun (the corresponding treatment was EG), and to analyze its effects on grain yield, WUE and NUE. The results showed that the water application uniformity coefficients of R3000, D3000 and P85A along the radial direction of the pivot (CUH) were 87.5, 79.5 and 65%, respectively. While the uniformity coefficients along the traveling direction of the pivot (CUC) were all higher than 85%. The effects of water application uniformity of the R3000 and D3000 sprinklers on grain yield were not significant (P>0.05);however, the average grain yield of EG was significantly lower (P<0.05) than those of RS and DS, by 9.4 and 11.1% during two growing seasons, respectively. The coefficients of variation (CV) of the grain yield had a negative correlation with the uniformity coefficient. The CV of WUE was more strongly affected by the water application uniformity, compared with the WUE value, among the three treatments. The NUE of RS was higher than those of DS and EG by about 6.1 and 4.8%, respectively, but there were no significant differences in NUE among the three treatments during the two growing seasons. Although the CUH of the D3000 sprinklers was lower than that of the R3000, it had only limited effects on the grain yield, WUE and NUE. However, the cost of D3000 sprinklers is lower than t 展开更多
关键词 center pivot low pressure sprinkler water application uniformity winter wheat water and nitrogen use efficiency
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城市建设用地开发强度与效益的动态响应关系--以兰州市为例 认领
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作者 白海江 《国土与自然资源研究》 2020年第3期41-45,共5页
研究城市建设开发强度与利用效益之间的关系,明确城市建设用地利用效益对城市建设用地开发强度响应程度。以兰州市为研究对象,对2001~2016年城市建设用地开发强度和利用效益进行评价,并借助响应度模型研究了两者的动态响应关系。研究结... 研究城市建设开发强度与利用效益之间的关系,明确城市建设用地利用效益对城市建设用地开发强度响应程度。以兰州市为研究对象,对2001~2016年城市建设用地开发强度和利用效益进行评价,并借助响应度模型研究了两者的动态响应关系。研究结果:(1)2001~2016年城市建设用地开发强度持续增长,效益提升显著;(2)城市建设用地利用效益变化对城市建设用地开发强度的增长始终表现出"正响应"特征,2001~2007年响应程度逐渐减弱,而2007~2016年响应程度逐渐增强;(3)城市建设用地利用效益与各影响因素呈现正相关关系,地均二三产业产值正向促进作用显著,城市建设用地比重对城市建设用地利用效益提升的作用次之。 展开更多
关键词 建设用地 城市建设用地开发强度 利用效益 响应度模型 兰州市
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Spatio-temporal variations of vegetation carbon use efficiency and potential driving meteorological factors in the Yangtze River Basin 认领
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作者 YE Xu-chun LIU Fu-hong +2 位作者 ZHANG Zeng-xin XU Chong-yu LIU Jia 《山地科学学报:英文版》 SCIE CSCD 2020年第8期1959-1973,共15页
Understanding of the vegetation dynamics is essential for addressing the potential threats of terrestrial ecosystem.In recent years,the vegetation coverage of the Yangtze River Basin(YRB)has increased significantly,ye... Understanding of the vegetation dynamics is essential for addressing the potential threats of terrestrial ecosystem.In recent years,the vegetation coverage of the Yangtze River Basin(YRB)has increased significantly,yet the spatio-temporal variations and potential driving meteorological factors of carbon use efficiency(CUE)under the context of global warming are still not clear.In this study,MODIS-based public-domain data during 2000–2015 was used to analyze these aspects in the YRB,a large river basin with powerful ecological functions in China.Spatio-temporal variations of CUE in different sub-basins and land cover types were investigated and the correlations with potential driving meteorological factors were examined.Results revealed that CUE in the YRB had strong spatiotemporal variability and varied remarkably in different land cover types.For the whole YRB,the average CUE of vegetated land was 0.519,while the long-term change trend of CUE was obscure.Along the rising altitude,CUE generally showed an increasing trend until the altitude of 3900 m and then followed by a decreasing trend.CUE of grasslands was generally higher than that of croplands,and then forest lands.The inter-annual variation of CUE in the YRB is likely to be driven by precipitation as a strong positive partial correlation between the inter-annual variability of CUE and precipitation was observed in most of sub-basins and land cover types in the YRB.The influence of temperature and relative humidity is also outstanding in certain regions and land cover types.Our findings are useful from the view point of carbon cycle and reasonable land cover management under the context of global warming. 展开更多
关键词 Carbon use efficiency Climate variability MODIS ALTITUDE Land cover type PRECIPITATION
山东省64排及以上CT配置使用情况分析 认领
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作者 李亚 许海弦 《中国医疗设备》 2020年第5期144-148,共5页
本文通过对我省各级各类医疗机构配置的64及以上CT年度使用数据进行调查研究,针对其配置数量、资金来源、使用效率、性能分布、维修保养情况、质检力度及频率等方面,开展数据分析。本文对以上数据分析结果进行阐述,针对存在的问题提出... 本文通过对我省各级各类医疗机构配置的64及以上CT年度使用数据进行调查研究,针对其配置数量、资金来源、使用效率、性能分布、维修保养情况、质检力度及频率等方面,开展数据分析。本文对以上数据分析结果进行阐述,针对存在的问题提出了相关建议与对策,为加强我省64排及以上CT配置事中、事后监管提供科学参考。 展开更多
关键词 64排及以上CT CT配置 使用效率 质量控制
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大型仪器共享系统与国家网络平台的对接与应用 认领
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作者 刘淑云 胡美琴 +1 位作者 王文君 刘洪颜 《实验室研究与探索》 CAS 北大核心 2020年第2期296-299,共4页
大型仪器共享服务系统与国家网络管理平台对接系统,属于平台对接系统技术领域。将大型仪器共享服务平台纳入国家网络管理平台,通过技术开发形成接口,实现国家网络管理平台与在线服务平台的深度融合,打通作业流程和数据流动渠道,形成平... 大型仪器共享服务系统与国家网络管理平台对接系统,属于平台对接系统技术领域。将大型仪器共享服务平台纳入国家网络管理平台,通过技术开发形成接口,实现国家网络管理平台与在线服务平台的深度融合,打通作业流程和数据流动渠道,形成平台之间管理、服务、评价等功能有机衔接,实现"将管理单位的大型仪器共享服务系统纳入国家网络管理平台"。对接系统包括大型仪器共享服务系统、国家网络管理平台对接系统、对接接口。对接接口基于HTTPS协议,使用WebService技术开发,实现大型仪器共享服务系统与国家网络管理平台在数据、服务两个方面的对接。 展开更多
关键词 大型仪器设备 资源共享 平台对接 使用效益 利用率
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Arabidopsis under ammonium over-supply: Characteristics of ammonium toxicity in relation to the activity of ammonium transporters 认领
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作者 Yi LI Jinyan ZHOU +2 位作者 Dongli HAO Shunying YANG Yanhua SU 《土壤圈:英文版》 SCIE CAS CSCD 2020年第3期314-325,共12页
Because of highly intensive farming practices, crop plants could suffer relatively long terms of ammonium(NH4+) excess stress introduced by overdose application of nitrogen fertilizers. However, the lack of sufficient... Because of highly intensive farming practices, crop plants could suffer relatively long terms of ammonium(NH4+) excess stress introduced by overdose application of nitrogen fertilizers. However, the lack of sufficient understanding of plant responses to NH4+excess stress impairs the detection of effective solutions to this problem. The present work examined the biological influences of over-supplied NH4+in Arabidopsis thaliana using two mutant lines each with an ammonium transporter(AMT) gene(AtAMT1;1 or AtAMT1;3) knocked out. Our results indicated that lacking one of the major components of root NH4+-absorbing systems significantly alleviated the toxicity effects on Arabidopsis plants by reducing the accumulation of free NH4+, suggesting that persistent absorption of NH4+through AMT was the main cause of excessive accumulation of free NH4+in the plants. Shading treatment led to a reduced transpirational driving force and thereby constrained the accumulation of toxic NH4+in the plants, finally resulting in higher NH4+-promoted growth in the wild type(WT). Under the shading treatment, the amt1;1 and amt1;3 mutant plants acquired insufficient NH4+and showed reduced growth when compared with the WT. Furthermore, the foliar application of sucrose notably alleviated the inhibitory effects on plant growth in the WT but had no effect on either the amt1;1 or amt1;3 mutant plants, indicating that carbon scarcity associated with NH4+excess is probably a major cause of NH4+toxicity in plants. Accordingly,increasing carbon source could be a potentially effective approach that alleviates the inhibition caused by NH4+excess and increases nitrogen use efficiency under NH4+over-supply. 展开更多
关键词 carbon and nitrogen synergy nitrogen use efficiency stress mechanism sucrose foliar spray toxicity alleviation transporter knockout
Short-term Response of Photosynthesis and Chlorophyll Content to Salinity Stress in Two Mangrove Species:Aegiceras corniculatum and Kandelia candel 认领
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作者 Xiaoyue WANG Ruili LI 《气象与环境研究:英文版》 CAS 2020年第3期60-63,69,共5页
There were fewer comparative studies on the adaptability of mangrove plants with two different salt secretion mechanisms to salinity stress. In this study,the seedlings of mangrove plants Aegiceras corniculatum and Ka... There were fewer comparative studies on the adaptability of mangrove plants with two different salt secretion mechanisms to salinity stress. In this study,the seedlings of mangrove plants Aegiceras corniculatum and Kandelia candel were selected as the research objects,and the methods of hydroponics with different salinity gradients were used. The salinity of 0‰,10‰,and 30‰ was applied respectively to simulate the adaptability of seedlings at low,moderate,and severe salinity stresses. Based on the results,the short-term responses of photosynthesis and chlorophyll content to salinity stress in two mangrove species with different salt secretion mechanisms were analyzed and discussed. The results show that A. corniculatum was more tolerant to10‰ salinity than K. candel,and the net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance( Gs) and water use efficiency(WUE)were also relatively higher;both A. corniculatum and K. candel could acclimate the low salinity(0‰),but showed severe osmotic stress at 30‰ salinity;A. corniculatum was more sensitive to severe salinity(30‰) than K. candel. These results can be of help to provide a theoretical support for the selection of species for mangrove wetlands restoration and seedlings acclimatization in tidal flats. 展开更多
关键词 Salinity stress Net photosynthetic rate Stomatal conductance Water use efficiency Chlorophyll content
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Rhizosphere Aeration Improves Nitrogen Transformation in Soil, and Nitrogen Absorption and Accumulation in Rice Plants 认领
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作者 XU Chunmei CHEN Liping +3 位作者 CHEN Song CHU Guang WANG Danying ZHANG Xiufu 《水稻科学:英文版》 SCIE CSCD 2020年第2期162-174,共13页
Two rice cultivars(Xiushui 09 and Chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice plants.The treatments were cont... Two rice cultivars(Xiushui 09 and Chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice plants.The treatments were continuous flooding(CF),continuous flooding and aeration(CFA),and alternate wetting and drying(AWD).The results showed that the AWD and CFA treatments improved soil N transformation,rice growth,and N absorption and accumulation.Soil NO3–content,nitrification activity and ammonia-oxidising bacteria abundance,leaf area,nitrate reductase activity,and N absorption and accumulation in rice all increased in both cultivars.However,soil microbial biomass carbon and pH did not significantly change during the whole period of rice growth.Correlation analysis revealed a significant positive correlation between the nitrification activity and ammonia-oxidising bacteria abundance,and both of them significantly increased as the total N accumulation in rice increased.Our results indicated that improved soil O2 conditions led to changing soil N cycling and contributed to increases in N absorption and accumulation by rice in paddy fields. 展开更多
关键词 ammonium-nitrogen CONTENT nitrate-nitrogen CONTENT NITRIFICATION ACTIVITY nitrate reductase ACTIVITY RHIZOSPHERE oxygen condition ammonia-oxidising bacteria abundance rice NITROGEN use efficiency
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Agriculture Green Development: a model for China and the world 认领
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作者 Jianbo SHEN Qichao ZHU +12 位作者 Xiaoqiang JIAO Hao YING Hongliang WANG Xin WEN Wen XU Tingyu LI Wenfeng CONG Xuejun LIU Yong HOU Zhenling CUI Oene OENEMA William JDAVIES Fusuo ZHANG 《农业科学与工程前沿:英文版》 2020年第1期5-13,共9页
Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’... Realizing sustainable development has become a global priority.This holds,in particular,for agriculture.Recently,the United Nations launched the Sustainable Development Goals(SDGs),and the Nineteenth National People’s Congress has delivered a national strategy for sustainable development in China—realizing green development.The overall objective of Agriculture Green Development(AGD)is to coordinate"green"with"development"to realize the transformation of current agriculture with high resource consumption and high environmental costs into a green agriculture and countryside with high productivity,high resource use efficiency and low environmental impact.This is a formidable task,requiring joint efforts of government,farmers,industry,educators and researchers.The innovative concept for AGD will focus on reconstructing the whole crop-animal production and food production-consumption system,with the emphasis on high thresholds for environmental standards and food quality as well as enhanced human well-being.This paper addresses the significance,challenges,framework,pathways and potential solutions for realizing AGD in China,and highlights the potential changes that will lead to a more sustainable agriculture in the future.Proposals include interdisciplinary innovations,whole food chain improvement and regional solutions.The implementation of AGD in China will provide important implications for the countries in developmental transition,and contribute to global sustainable development. 展开更多
关键词 Agriculture Green Development food security interdisciplinary innovations resource use efficiency sustainable development sustainable intensification whole industry chain
Can crop science really help us to produce more betterquality food while reducing the world-wide environmental footprint of agriculture? 认领
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作者 William J.DAVIES Susan E.WARD Alan WILSON 《农业科学与工程前沿:英文版》 2020年第1期28-44,共17页
This paper reviews recent developments in crop science that can be the basis of a revolution in the global food system but it is also emphasized that such a revolution requires more than changes in food production and... This paper reviews recent developments in crop science that can be the basis of a revolution in the global food system but it is also emphasized that such a revolution requires more than changes in food production and supply.We must more effectively feed a growing global population with a healthy diet while also defining and delivering the kinds of sustainable food systems that will minimise damage to our planet.There are exciting new developments in crop production biology but much existing crop science can be exploited to increase yields with the aid of a knowledge exchange(KE)framework requiring the use of new technology now available to most people across the globe.We discuss novel approaches at both the plant and the crop level that will enhance nutrient and water productivity and we also outline ways in which energy use and greenhouse gas(GHG)emissions can be reduced and labor shortages combatted.Exploitation of new biology and new engineering opportunities will require development of public-private partnerships and collaborations across the disciplines to allow us to move effectively from discovery science to practical application.It is also important that consumers contribute to the debate over proposed changes to food and farming and so effective KE mechanisms are required between all relevant communities. 展开更多
关键词 food security environmental sustainability crop water use efficiency crop science diet and health
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