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Effects of Different Seed Stem Sizes on the Changes of Available Elements in Rhizosphere Soil of Fritillaria thunbergii Miq.
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作者 Yong PENG Rui PAN +3 位作者 Zhengyan LIU Xiaohong WU Nong ZHOU Wenwu YANG 《Agricultural Biotechnology》 2024年第3期18-23,共6页
[Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F... [Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F.thunbergii Miq.introduced to different places.[Methods]F.thunbergii Miq.from four different provenances including Zhejiang,Nantong and Chongqing were introduced and cultivated in Wanzhou of Chongqing.The contents of available Zn,Fe,Mn,Cu,Mo,N,P,K,Ca and Mg in rhizosphere soil of F.thunbergii Miq.during five growing stages were determined after selecting different stem sizes for field cultivation.[Results]Small stems of Pan an and Ningbo provenances(SSG3,121-160/kg)and middle stems of Nantong and Fengjie provenances(SSG2,81-120/kg)showed higher soil availability.[Conclusions]In the process of introduction and cultivation of F.thunbergii Miq.,high yield and high efficiency can be achieved by selecting smaller seed stems of F.thunbergii Miq. 展开更多
关键词 Fritillaria thunbergii Miq. Different provenances Stem size INTRODUCTION CULTIVATION Soil nutrient element AVAILABILITY
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Available parking space occupancy change characteristics and short-term forecasting model 被引量:5
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作者 季彦婕 王炜 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期604-608,共5页
Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-secti... Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-sections are periodical and self-similar, and the fluctuation of the APSO increases with the decrease in time-sections. Taking the short-time change behavior into account, an APSO forecasting model combined wavelet analysis and a weighted Markov chain is presented. In this model, an original APSO time series is first decomposed by wavelet analysis, and the results include low frequency signals representing the basic trends of APSO and several high frequency signals representing disturbances of the APSO. Then different Markov models are used to forecast the changes of low and high frequency signals, respectively. Finally, integrating the predicted results induces the final forecasted APSO. A case study verifies the applicability of the proposed model. The comparisons between measured and forecasted results show that the model is a competent model and its accuracy relies on real-time update of the APSO database. 展开更多
关键词 available parking space occupancy change characteristics short-term forecasting wavelet analysis weighted Markov chain
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element available content The affecting factors Western Jilin
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不同施肥模式对大豆生长季土壤有效氮供给的影响
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作者 丁世杰 黄绍敏 +5 位作者 张水清 郭斗斗 宋晓 张珂珂 岳克 郭腾飞 《核农学报》 CAS 北大核心 2025年第2期391-403,共13页
为探究施肥模式对潮土区大豆生长季土壤有效氮供给的影响,本研究基于33年长期定位施肥试验,选取4种处理:不施肥(CK)、施氮磷钾化肥(NPK)、氮磷钾化肥+秸秆还田(SNPK)与氮磷钾化肥+有机肥(MNPK),测定分析大豆生长季内土壤铵态氮(NH_(4)^(... 为探究施肥模式对潮土区大豆生长季土壤有效氮供给的影响,本研究基于33年长期定位施肥试验,选取4种处理:不施肥(CK)、施氮磷钾化肥(NPK)、氮磷钾化肥+秸秆还田(SNPK)与氮磷钾化肥+有机肥(MNPK),测定分析大豆生长季内土壤铵态氮(NH_(4)^(+)-N)、硝态氮(NO_(3)^(-)-N)、微生物量氮、可溶性有机氮含量的变化动态,以及参与土壤氮素转化的有机氮矿化酶活性、氨化作用强度与硝化潜势。结果表明,化肥与秸秆或有机肥配施可提高土壤全氮、有机碳、微生物量碳和可溶性有机碳含量,这对土壤脲酶、酰胺酶、蛋白酶和N-乙酰-β-D-葡萄糖苷酶活性及氨化作用强度和硝化潜势的提升有不同程度的促进作用。土壤NH_(4)^(+)-N含量与脲酶和蛋白酶活性呈极显著正相关,与酰胺酶活性呈显著正相关;NO_(3)^(-)-N含量与氨化作用强度、硝化潜势呈极显著正相关。SNPK、MNPK处理下的土壤微生物量氮和可溶性有机氮含量均高于NPK、CK处理。潮土可溶性有机氮含量与大豆地上部氮素吸收呈极显著正相关,并最终影响大豆生长;成熟期SNPK、MNPK处理下的大豆地上部生物量均高于CK、NPK处理。综上所述,化肥与秸秆或有机肥配施可通过提高全氮、有机碳和活性有机碳含量正向调控土壤氮素转化微生物作用强度与酶活性,提高土壤有效氮供给能力,促进大豆生长。本试验结果可为潮土区合理施肥提供理论依据。 展开更多
关键词 施肥模式 有效氮 有机氮矿化酶 氨化作用强度 硝化潜势
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Spatial Variation Characteristics of Soil Available Plumbum (Pb) in Vegetable Bases in Urumqi City 被引量:1
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作者 郑江 王灵 《Agricultural Science & Technology》 CAS 2012年第1期155-157,167,共4页
[Objective] The paper was to study the spatial variation characteristics of soil available plumbum (Pb) in vegetable bases of Urumqi City. [Method] With the vegetable base in northern suburb of Urumqi city as a typi... [Objective] The paper was to study the spatial variation characteristics of soil available plumbum (Pb) in vegetable bases of Urumqi City. [Method] With the vegetable base in northern suburb of Urumqi city as a typical area, the structure feature of soil available Pb content in suburb of oasis city in the arid area was ana- lyzed to get the spatial distribution pattern of available Pb, the origin and pollution source of this distribution pattern were also revealed. [Result] The available Pb in vegetable base of northern suburb in Urumqi City belonged to moderate variation. Semivariance model fitting showed that available Pb content could be fit with expo- nential function, which had spatial correlation within a certain range. The spatial dis- tribution pattern of available Pb content was obtained by using optimal Kriging inter- polation, and indicated that soil available Pb content was closely related to industrial activities, sewage irrigation and atmospheric dust. [Conclusion] The study provided the scientific basis for recognition, pollution risk assessment and pollution control of Pb pollution sources in the region, which have great significance on creating safe and clean production environment and selecting reasonable vegetable planting districts. 展开更多
关键词 URUMQI Soil Pb available state Spatial variation
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Influence of Phosphorus Fertilizer Application on Available Phosphorus and Easy-loss Phosphorus Content in Red Soil
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作者 赵牧秋 陈欣 史云峰 《Agricultural Science & Technology》 CAS 2012年第3期570-573,577,共5页
[Objective] This study was to investigate the influence of phosphorus (P) fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoret... [Objective] This study was to investigate the influence of phosphorus (P) fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoretical basis for the management of elemental P and evaluation of elemental P loss potential. [Method] Totally six treat- ments were set to the soil samples. The Olsen-P, Bray-1 P and CaCl2-P contents of each soil sample were measured after indoor aerobic incubation. [Result] In the red soil of different P fertilizer application rates, the Olsen-P content decreased with the increasing of incubation time, while the content of Bray-1 P increased and CaCI2-P content was first increased then decreased. CaCl2-P content was linear correlated with Olsen-P content and Bray-1 P content. About 62% P fertilizers were transformed into Bray-1 P pool, and 14% into Olsen-P pool, but only 0.12% transformed into CaCl2-P pool. [Conclusion] There is little risk of P loss caused by P fertilizer application under aerobic condition, but it would increase with the increasing application dose, and the most serious time is the primeval period after P fertilizer application. 展开更多
关键词 Phosphorus fertilizer available phosphorus Red soil INCUBATION
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Effects of Nitrogen Fertilization Amount on the Prophase Yield of Phaseolus vulgaris and Available Nitrogen Content of Soil
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作者 汤国民 于立芝 《Agricultural Science & Technology》 CAS 2016年第8期1889-1891,共3页
[Objective] This study aimed to provide certain scientific basis for reasonable application of nitrogen fertilizer in the pollution-free cultivation of Phaseolus vulgaris. [Method] A field experiment was conducted to ... [Objective] This study aimed to provide certain scientific basis for reasonable application of nitrogen fertilizer in the pollution-free cultivation of Phaseolus vulgaris. [Method] A field experiment was conducted to investigate the effects of different nitrogen fertilization amounts on the prophase yield and economic efficiency of P. vulgaris and available nitrogen content of soil. [Result] With the increased application amount of nitrogen fertilizer, the prophase yield and economic efficiency of P. vulgaris reached the peaks in the Treatment 3 (8 690.48 kg/ hm^2 and 32 222 yuan/hm^2), and significant differences were found among different treatment groups. With the increased nitrogen fertilization amount, the soil available nitrogen content increased, showing a positive correlation with correlation coefficient of 0.856 5. Excess nitrogen fertilizer reduced the prophase yield and economic efficiency of P. vulgaris. For the open field cultivation of P. vulgaris, the optimum application amount of nitrogen fertilizer was 178 kg/hm^2. [Conclusion] Application of nitrogen fertilizer could effectively increase the soil available nitrogen content. 展开更多
关键词 Nitrogen fertilizer Phaseolus-vulgaris Prophase yield Soil available nitrogen
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Effects of Growing of Different Types of Crops on Constitution of Soil Available Nitrogen and Conversion and Utilization of Nitrogen Fertilizer
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作者 曾科 杨兰芳 +2 位作者 于婧 李彬波 汪正祥 《Agricultural Science & Technology》 CAS 2017年第6期1067-1071,1075,共6页
The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined... The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined, so as to provide techni- cal guidance for reasonable use and improving use efficiency of nitrogen fertilizer for different types of crops. Compared with the control with nitrogen but unplanted crop, growing soybean, cotton, maize, sorghum significantly decreased the soil available N contents by 53. 48%, 51.54%, 33.10%, 55.03%,and influenced the constitution of soil available N. Thereinto, growing soybean, cotton, maize and sorghum significantly decreased soil inorganic N contents by 85.41%, 83.09%, 70.89% and 83.35%,but increased soil hydrolysable organic N contents by 1.41, 1.53, 2.11 and 1.28 times, respectively; growing soybean, cotton, maize and sorghum significantly decreased the rate of soil inorganic N to available N by 68.61%, 65.09%, 56.47% and 63.00%, but increased the rate of soil hydrolysable organic N to available N by 4.18, 4.21, 3.66 and 4.08 times, respectively. Compared with the control, growing soybean, cotton, maize and sorghum significantly increased the transform rate of ammonium nitrogen fertilizer by 93.66%, 38.19%, 32.58% and 38.31% respectively, and growing soybean treatment had the highest increasing range; the nitrification rates of ammo- nium nitrogen fertilizer of growing soybean, cotton, maize and sorghum treatments were negative values, and growing soybean treatment had the highest decreasing amplitude. The ammonium nitrogen fertilizer use efficiency of growing soybean, cot- ton, maize and sorghum treatments were 52.01%, 28.31%, 24.16% and 28.40% re- spectively and growing soybean treatment had the highest value. In conclusion, growing crops suppressed the soil nitrification and accelerated the development of soil hydrolysable organic nitrogen by the utilization of soil available nitrogen and the alteration of soil environment, and hence impacted the constitution of soil available nitrogen and the transform and use of ammonium nitrogen applied in soil. Legumi- nous crops had stronger ability of suppressing nitrification, making use of ammonium compared with non-Leguminous crops. 展开更多
关键词 Growing of crops available nitrogen Ammonium nitrogen Nitrate nitro-gen Hydrolysable organic nitrogen Nitrogen fertilizer use efficiency
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Telemedicine and public health–pearls and pitfalls
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作者 Ranjeet Kumar Sinha Sony Sinha +2 位作者 Prateek Nishant Arvind Kumar Morya Arshi Singh 《World Journal of Methodology》 2025年第2期177-179,共3页
We hereby comment on the interesting systematic review by Grewal et al where they have provided an overall picture of the current status of available tele-health programs in the United States with emphasis on the Amaz... We hereby comment on the interesting systematic review by Grewal et al where they have provided an overall picture of the current status of available tele-health programs in the United States with emphasis on the Amazon Clinic.Their analysis is an appreciable effort in discovering the features available and features lacking in these tele-health programs.The concept of tele-health originated to curtail the need for physical attendance of patients at health clinics,and has been beneficial during the coronavirus disease 2019 pandemic.We implore that the pearls and pitfalls of these programs have to be understood by policymakers prior to forming a consensus regarding the availability,accessibility and affordability of these programs as methods of healthcare delivery.Unrestricted proliferation of tele-health programs in their current form may pose threats to patient and provider safety and medicolegal liability.However,patients and providers must work together to improve them to meet their expectations and enable them to provide the best care for the ailing public. 展开更多
关键词 TELEMEDICINE Remote Access Availability Accessibility AFFORDABILITY ETHICS Privacy Medicolegal liability
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Analysis and Producing Causes of Available Sulphur Status quo(Rich or Insufficient) in Farmlands and Countermeasures in Dengzhou City
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作者 张有成 《Agricultural Science & Technology》 CAS 2014年第8期1348-1350,共3页
In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and ab... In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and about 60% farmlands with available sulphur belong to the farmlands with potential shortage of available sulphur for Cruciferae, Liliaceae and Leguminosae. Meanwhile, the producing causes were analyzed from the perspectives of fertilization structure and planting structure and the countermeasures were proposed in terms of sulphur movements in plants and characters. 展开更多
关键词 available sulphur S Rich or insufficient COUNTERMEASURES
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谈谈available在医学文献中的译法
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作者 何祖佳 《世界今日医学杂志》 2002年第9期793-794,共2页
关键词 医学文献 available 译法
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Distribution of available soil water capacity in China 被引量:60
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Strategies for multi-step-ahead available parking spaces forecasting based on wavelet transform 被引量:4
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作者 JI Yan-jie GAO Liang-peng +1 位作者 CHEN Xiao-shi GUO Wei-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1503-1512,共10页
A new methodology for multi-step-ahead forecasting was proposed herein which combined the wavelet transform(WT), artificial neural network(ANN) and forecasting strategies based on the changing characteristics of avail... A new methodology for multi-step-ahead forecasting was proposed herein which combined the wavelet transform(WT), artificial neural network(ANN) and forecasting strategies based on the changing characteristics of available parking spaces(APS). First, several APS time series were decomposed and reconstituted by the wavelet transform. Then, using an artificial neural network, the following five strategies for multi-step-ahead time series forecasting were used to forecast the reconstructed time series: recursive strategy, direct strategy, multi-input multi-output(MIMO) strategy, DIRMO strategy(a combination of the direct and MIMO strategies), and newly proposed recursive multi-input multi-output(RECMO) strategy which is a combination of the recursive and MIMO strategies. Finally, integrating the predicted results with the reconstructed time series produced the final forecasted available parking spaces. Three findings appear to be consistently supported by the experimental results. First, applying the wavelet transform to multi-step ahead available parking spaces forecasting can effectively improve the forecasting accuracy. Second, the forecasting resulted from the DIRMO and RECMO strategies is more accurate than that of the other strategies. Finally, the RECMO strategy requires less model training time than the DIRMO strategy and consumes the least amount of training time among five forecasting strategies. 展开更多
关键词 available PARKING SPACES MULTI-STEP AHEAD time series forecasting wavelet transform forecasting STRATEGIES recursive multi-input MULTI-OUTPUT strategy
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Preliminary Study on Spatial Variability and Distribution of Soil Available Microelements in Pinggu County, Beijing, China 被引量:3
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作者 WANG Shu-ying YU Tong-quan WANG Jian-li YANG Liu YANG Kai LU Ping 《Agricultural Sciences in China》 CAS CSCD 2008年第10期1235-1244,共10页
The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from P... The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from Pinggu County of Beijing, China, and the contents of available Cu, Zn, Fe, and Mn in topsoil (0-20 cm) and subsoil (20-40 cm) were analyzed respectively. Descriptive statistics and geostatistics were used to analyze the data. The mean values of topsoil available Cu, Zn, Fe, and Mn were 1.96, 2.51, 17.32, and 10.91 mg kg^-1, respectively, which were at medium or at slightly above medium level. The topsoil content of the soil available microelements was more than that of subsoil. The result of semivariance analysis showed that the topsoil available Fe and Mn were spatially correlated at a larger distance of 21.6 and 45.3 km, and the available Cu and Zn were at a shorter distance of 3.1 and 2.9 km, respectively. The subsoil spatial correlation distances were obviously different from the topsoil, which were in the order of available Mn 〉 Cu 〉 Zn = Fe. The Kriging method was applied to calculate the unobserved points and was used to generate the contour map. The results showed that the structural factors, such as topology, soil types, and soil properties, were the main factors influencing the spatial distribution of topsoil available Fe and Mn. Topsoil available Cu and Zn contents were mainly affected by land use, and their contents in orchard and in vegetable land were greatly higher than in field. The spatial distribution of subsoil microelements was similar to that of the topsoil, which exhibited vertical distribution patterns. Fertilizer and pesticide application resulted in the higher contents of available Cu and Zn in Pinggu County. The higher content of available Zn is potentially harmful to soil environmental quality, which should be inspected. 展开更多
关键词 soil available microelements SEMIVARIANCE spatial variability
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A model to estimate available timber and forest biomass and reforestation expenses in a mountainous region in Japan 被引量:2
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作者 Kazuhiro Aruga Ayami Murakami +3 位作者 Chikara Nakahata Reiko Yamaguchi Masashi Saito Kanae Kanetsuki 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期345-356,共12页
We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimat... We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimated while considering not only harvesting expenses but also reforestation expenses after final felling, which should be considered for sustainable forest management. Harvesting expenses were estimated based on two types of timber harvesting systems and three types of forest biomass harvesting systems in each sub-compartment. Then, the model was applied to Nasushiobara city of Tochigi prefecture, Japan. Reforestation expenses had large negative impacts on the financial balances of final felling operations. Few sub-compartments were profitable after considering reforestation expenses. Most profitable sub-compartments were those with mechanized operation systems and landing sales. These accounted for 17.19% of all sub-compartments, while only 5.75% of the sub-compartments were profitable based on their current operation systems and landing sales. Although the overall supply potentials of timber and forest biomass resources were 380,000 m3 and 210,000 Mg, respectively, and 15 times the planned harvest of coniferous tree volume of 25,000 m3year-1 and 50 times the annual demand for the woody gasification power generation of 4,000 Mg year-1 in Nasushiobara, available amounts of timber and forest biomass resources were only49,429 m3 and 33,333 Mg, which were 13.0% and 15.7% of supply potentials for landing sales with mechanized operation systems. 展开更多
关键词 forest biomass resources supply potentials available amounts economic balance GIS
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Study on the Uncertainty of the Available Time Under Ship Fire Based on Monte Carlo Sampling Method 被引量:2
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作者 汪金辉 褚冠全 李开源 《China Ocean Engineering》 SCIE EI CSCD 2013年第1期131-140,共10页
Available safety egress time under ship fire (SFAT) is critical to ship fire safety assessment, design and emergency rescue. Although it is available to determine SFAT by using fire models such as the two-zone fire ... Available safety egress time under ship fire (SFAT) is critical to ship fire safety assessment, design and emergency rescue. Although it is available to determine SFAT by using fire models such as the two-zone fire model CFAST and the field model FDS, none of these models can address the uncertainties involved in the input parameters. To solve this problem, current study presents a framework of uncertainty analysis for SFAT. Firstly, a deterministic model estimating SFAT is built. The uncertainties of the input parameters are regarded as random variables with the given probability distribution functions. Subsequently, the deterministic SFAT model is employed to couple with a Monte Carlo sampling method to investigate the uncertainties of the SFAT. The Spearman's rank-order correlation coefficient (SRCC) is used to examine the sensitivity of each input uncertainty parameter on SFAT. To illustrate the proposed approach in detail, a case study is performed. Based on the proposed approach, probability density function and cumulative density function of SFAT are obtained. Furthermore, sensitivity analysis with regard to SFAT is also conducted. The results give a high-negative correlation of SFAT and the fire growth coefficient whereas the effect of other parameters is so weak that they can be neglected. 展开更多
关键词 ship fire ship fire available time Monte Carlo sampling uncertainty analysis sensitivity analysis
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Meso-scale available gravitational potential energy in the world oceans 被引量:2
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作者 FENG Yang WANG Wei HUANG Ruixin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第5期1-13,共13页
The pitfalls of applying the commonly used definition of available gravitational potential energy (AGPE) to the world oceans are re-examined. It is proposed that such definition should apply to the meso-scale proble... The pitfalls of applying the commonly used definition of available gravitational potential energy (AGPE) to the world oceans are re-examined. It is proposed that such definition should apply to the meso-scale problems in the oceans, not the global scale. Based on WOA98 climatological data, the meso-scale AGPE in the world oceans is estimated. Unlike previous results by Oort et al. , the meso-scale AGPE is large wherever there is a strong horizontal density gradient. The distribution of meso-scale AGPE reveals the close connection between the baroclinic instability and the release of gravitational potential energy stored within the scale of Rossby deformation radius. 展开更多
关键词 energy of ocean circulation available potential gravitational energy MESO-SCALE baroclinic instability Rossby deformation radius
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Spatial and Temporal Variations in Available Soil Nitrogen—A Case Study in Kobresia Alpine Meadow in the Qinghai-Tibetan Plateau, China 被引量:4
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作者 Li Lin Guangmin Cao +7 位作者 Fawei Zhang Xun Ke Yikang Li Xingliang Xu Qian Li Xiaowei Guo Bo Fan Yangong Du 《Journal of Geoscience and Environment Protection》 2019年第3期177-189,共13页
Elucidating the factors that determine the effects of temporal and spatial variation of nutrients is important for analyzing the characteristics of an ecosystem. The goal of this paper was to estimate how values obtai... Elucidating the factors that determine the effects of temporal and spatial variation of nutrients is important for analyzing the characteristics of an ecosystem. The goal of this paper was to estimate how values obtained using a particular sampling approach correlated with the actual data for an entire plot. The mesh partition method was employed to divide an integrated observing field (IOF) located at the Haibei National Field Research Station of an alpine grassland ecosystem, China, into 25 subplots. Five of the 25 subplots were randomly selected for soil sampling and to determine the source of variations in soil nutrient content from 2001 to 2012. The results showed that, contributions of temporal and spatial variation in available nitrogen in the 0 - 10 cm soil layer accounted for 47.3% and 52.7%, respectively. The contribution of spatial variance was higher than that of temporal variance especially in the surface soil layers. The available soil nitrogen content in the alpine meadow was not obviously affected by fluctuations in rainfall and temperature. Increasing the number of samples could reduce calculation errors in measuring available soil nitrogen content, while collecting a reasonable number of samples can save time and labor. 展开更多
关键词 available Soil Nitrogen Source of NUTRIENT VARIATION TEMPORAL VARIATION Spatial VARIATION ALPINE MEADOW
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Generalized Available Potential Energy 被引量:2
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作者 Yong.L.McHall 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第4期395-408,共14页
The kinetic energy generation in either the dry or moist atmosphere may be estimated by the same relationships if we introduce the new concept of generalized available potential energy. The largest magnitude of genera... The kinetic energy generation in either the dry or moist atmosphere may be estimated by the same relationships if we introduce the new concept of generalized available potential energy. The largest magnitude of generalized available potential energy and corresponding reference state of either dry or moist atmosphere are calculated in terms of the mitial conditions and entropy variation of the atmosphere. The obtained relationships are applicable for the statically unstable atmosphere as well. The generalized available potential energy associated with reversible processes reaches the maximum with respect to same initial state. While the generation of kinetic energy in irreversible processes is characterized by sudden changes. When the reference state is assumed to be saturated, we may predict the final temperature and moisture fields corresponding to provided initial state and entropy variation. 展开更多
关键词 Generalized available Potential Energy THAN AS
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Determination of the available energy values and amino acid digestibility of Flammulina velutipes stem waste and its effects on carcass trait and meat quality fed to growing-finishing pigs 被引量:6
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作者 Xuzhou Liu Bo Zhang +7 位作者 Hansuo Liu Gang Zhang Jinbiao Zhao Ling Liu Xiangshu Piao Hui Song Shuai Zhang Yu Li 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期747-766,共20页
Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate... Background:Flammulina velutipes stem waste(FVS)is the by-product of mushroom industry.The objectives of this study were to determine the available energy and amino acid digestibility of FVS fed to pigs,and to evaluate the effects of dietary FVS inclusion on growth performance,biochemical profile of serum,fecal short chain fatty acid(SCFA)concentration,carcass traits,meat quality,intestinal morphology and microflora of pigs.In Exp.1,twelve crossbred barrows with initial body weight(IBW)of 37.48±4.31 kg were randomly allotted to 2 dietary treatments,including a corn basal diet and an experimental diet containing 24.35%FVS.In Exp.2,twelve barrows fitted with an ileal T-cannula(IBW:32.56±1.67 kg)were randomly allotted to 2 dietary treatments,which included a N-free diet and an experimental diet containing 40.0%FVS.In Exp.3,ninety growing pigs(IBW:63.98±6.89 kg)were allotted to 1 of 3 treatment diets for 63 d,including a basal diet and 2 experimental diets with 2.5%and 5%FVS,respectively.Results:The digestible energy(DE)and metabolizable energy(ME)of FVS were 4.58 and 4.06 MJ/kg on dry matter basis,respectively,and the standardized ileal digestibility(SID)of indispensable AAs ranged from 17.50%to 59.47%.Pigs fed diets with 2.5%FVS showed no difference on average daily gain(ADG)and gain to feed ratio(G/F).Although dietary 5%FVS inclusion impaired apparent total tract digestibility(ATTD)of organic matter and gross energy,it elevated the SCFA concentration(P≤0.04)in gut and antioxidant capacity in serum.In addition,dietary FVS inclusion depressed the backfat thickness(P=0.03)in pigs.The longissimus dorsi muscle of pigs fed FVS revealed higher n-3 polyunsaturated fatty acid concentration and optimized fatty acid composition.Dietary 2.5%FVS inclusion also improved the intestinal development and health by increasing the villius height to crypt depth ratio(V/C)in jejunum(P<0.01),and promoting microbial diversity and beneficial microbiota proliferation.Conclusions:It is feasible to include moderate content of FVS as an unconventional fiber ingredient in diet of growingfinishing pigs. 展开更多
关键词 AMINO acid DIGESTIBILITY available energy Fiber Flammulina velutipes STEM WASTE Growing-finishing pigs Growth performance MEAT quality
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