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Experimental Study and Modeling of a Convective Dryer for Fruits and Vegetables
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作者 Souleymane Sinon Salifou Tera +3 位作者 Kayaba Haro El-Maktoume Djanfar Oumar Sanogo Sié Kam 《Engineering(科研)》 CAS 2023年第1期13-23,共11页
The present work deals with the study of the thermal performances of a convective dryer for fruits and vegetables. This dryer, operating with energy generated from the combustion of biomass in a boiler connected to a ... The present work deals with the study of the thermal performances of a convective dryer for fruits and vegetables. This dryer, operating with energy generated from the combustion of biomass in a boiler connected to a water/air heat exchanger could be a solution to the problematic of energy related to drying. An experimental and theoretical study is carried out on the temperature profile inside the dryer. For this purpose, 10.3 kg of tomatoes were dried on the experimental setup. The operation lasted about 16 hours and reduced the moisture content from 93.8% to 12% in wet basis. The overall thermal efficiency of the convective dryer during the trial is 10.76%. For the theoretical study, the dryer components (boiler, water/air exchanger and drying chamber) are first modeled individually;the different sub-programs are then coupled to form the convective dryer program. The method of global heat balances combined with the one called “ε-NUT” is used. The set of equations is discretized using the implicit method of finite differences, then solved with the Gauss algorithm in Fortran 90. The theoretical results obtained are in good agreement with those measured. 展开更多
关键词 Energy dryING biomass Boilers Fruits and Vegetables
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Drying Temperature Effect on Kernel Damage and Viability of Maize Dried in a Solar Biomass Hybrid Dryer
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作者 Joseph O. Akowuah Dirk Maier +5 位作者 George Opit Sam McNeill Paul Amstrong Carlos Campabadal Kingsly Ambrose George Obeng-Akrofi 《Open Journal of Applied Sciences》 2018年第11期506-517,共12页
Though several maize varieties have been developed and introduced over the years in Ghana, farmers still face challenges of access to quality seed maize. Among the major constraint is lack of proper drying systems to ... Though several maize varieties have been developed and introduced over the years in Ghana, farmers still face challenges of access to quality seed maize. Among the major constraint is lack of proper drying systems to guarantee quality of seed produced. As in most parts of Africa, drying of maize in the open, on bare ground along shoulders of roads is still a common practice in Ghana. In this study, a 5-tonne capacity hybrid solar biomass dryer was developed for drying maize for seed and food/feed in Ghana. Effect of air temperature in the dryer on the physiological quality and germination of maize kernels was investigated. Maize grains were dried in the open sun simulating farmers practice and using the dryer at 4 varying levels (L1, L2, L3 and L4) with corresponding heights (0.6 m, 1.2 m, 1.8 m and 2.4 m, respectively) from the ground. Harvested maize at 22.8% moisture content was dried at the varying levels until reaching the final desired moisture content of 12.8% ± 0.2% (wb). Results showed that, air temperatures in the dryer increased in accordance with height with lowest mean temperature of 44.4&degC ± 4.6&degC recorded at L1 and mean maximum of 52.8&degC ± 5.4&degC at L4. Drying temperatures recorded at L1 - L3 and ambient had no significant effect (p < 0.05) on kernel damage and viability. Drying conditions at L1-L3 were considered optimum (<50&degC) for kernel drying compared to the topmost tray, L4. Kernel stress crack index (multiple and checked) was therefore reduced on average by 14% while kernel germination increased by 33%. This satisfies the dryer’s potential to be used for commercial drying of maize grains for seed production for smallholder farmers in Ghana. 展开更多
关键词 SOLAR biomass HYBRID dryER dryING Temperature MAIZE Moisture Stress Crack Germination
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Stem and Total Above-Ground Biomass Models for the Tree Species of Freshwater Wetlands Forest, Coastal Areas and Dry Areas of Bangladesh: Using a Non-Destructive Approach
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作者 Mahmood Hossain Chameli Saha +4 位作者 Rakhi Dhali Srabony Saha Mohammad Raqibul Hasan Siddique S. M. Rubaiot Abdullah S. M. Zahirul Islam 《Open Journal of Forestry》 2021年第2期73-82,共10页
Biomass and carbon stock in a forested areas are now prime important indicators of forest management and climate change mitigation measures. But the accurate estimation of biomass and carbon in trees of forests is now... Biomass and carbon stock in a forested areas are now prime important indicators of forest management and climate change mitigation measures. But the accurate estimation of biomass and carbon in trees of forests is now a challenging issue. In most cases, pantropical and regional biomass models are used frequently to estimate biomass and carbon stock in trees, but these estimation</span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> have some uncertainty compared to the species-specific allometric biomass model. </span><i><span style="font-family:Verdana;">Acacia</span></i><span> <i><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Casuarina</span></i> <i><span style="font-family:Verdana;">equisetifolia</span></i></span><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Melia</span></i><span style="font-family:Verdana;"> <i>azedarach</i> </span><span style="font-family:Verdana;">have been planted in different areas of Bangladesh considering the species-specific site requirements. While </span><i><span style="font-family:Verdana;">Barringtonia</span></i><span style="font-family:Verdana;"> <i>acutangula</i></span><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Pongamia</span></i><span style="font-family:Verdana;"> <i>pinnata</i> </span><span style="font-family:Verdana;">are the dominant tree species of the freshwater swamp forest of Bangladesh. This study was aimed to develop species-specific allometric biomass models for estimating stem and above ground biomass (TAGB) of these species using the non-destructive method and to compare the efficiency of the derived biomass models with the frequently used regional and pantropical biomass models. Four Ln-based models with diameter at breast height (DBH) and total height (H) were tested to derive the best fit allometric model. Among the tested models, Ln (biomass) = a + b Ln (D) + c Ln (H) was the best-fit model for </span><i><span style="font-family:Verdana;">A</span></i><span><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">M</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">azedarach</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">B</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">acutangula</span></i> </span><span style="font-family:Verdana;">and</span><span> <i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">pinnata</span></i> </span><span style="font-family:Verdana;">and Ln (biomass) = a + b Ln (D</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">H) was best-fit for </span><i><span style="font-family:Verdana;">C</span></i><span><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">equisetifolia</span></i><span style="font-family:Verdana;">. </span></span><span style="font-family:Verdana;">Finally</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the derived best-fit species-specific TAGB models have shown superiority over the other frequently used pantropical and regional biomass models in relation to model efficiency and model prediction error. 展开更多
关键词 ALLOMETRY biomass Freshwater Wetlands Coastal Areas dry Areas
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城市污泥干燥动力学特性及其与生物质共气化热电联产系统模拟
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作者 任少辉 向家涛 +1 位作者 张世红 郭鹏 《热力发电》 CAS CSCD 北大核心 2024年第3期1-13,共13页
对城市污泥进行高效干燥预处理及气化资源化利用是实现城市绿色可持续发展的重要途径之一。首先,利用热重反应器研究了污泥的干燥动力学特性;其次,基于Fluent数值模拟软件明晰了高温低速烟气和低温高速烟气对污泥干燥过程的影响;最后通... 对城市污泥进行高效干燥预处理及气化资源化利用是实现城市绿色可持续发展的重要途径之一。首先,利用热重反应器研究了污泥的干燥动力学特性;其次,基于Fluent数值模拟软件明晰了高温低速烟气和低温高速烟气对污泥干燥过程的影响;最后通过Aspen Plus构建了新型的污泥与生物质共气化热电联产系统,并讨论了系统的热力性能。结果表明:污泥在热重反应器中的干燥过程分为升速阶段、第一降速阶段和第二降速阶段,以降速阶段为主;SW-60、SW-80的水分扩散系数范围分别为6.34×10^(-6)~3.72×10^(-5)m^(2)/s和3.69×10^(-5)~2.60×10^(-4)m^(2)/s;初始含水率的提高会增加污泥干燥活化能,SW-60、SW-80的干燥活化能分别为9.55 kJ/mol和28.25 kJ/mol;干燥床中高温低速烟气的干燥效率大约为低温高速烟气的2.67倍;在热电联产系统中,随着生物质掺混比例的增加,输入热量、空气流量、合成气低位热值、合成气产率和热电联产潜力均随之增加,然而电效率、热效率和系统效率会缓慢下降;当生物质掺混质量比为20%时,每千克30%含水率干污泥与生物质的共混物可以产生电能与热能潜力分别为0.61 k W·h和4.212 MJ。 展开更多
关键词 城市污泥 干燥动力学 生物质 共气化 热电联产
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大豆玉米复合种植模式中2种作物的互作关系
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作者 李耀宇 李富忠 +3 位作者 张吴平 邓子正 屈腾腾 赵其昕 《山西农业科学》 2024年第2期16-20,共5页
定量化探索中国北方在平水年下,不同大豆玉米复合种植模式的种间竞争与种间互惠关系,以期为旱作条件下选择合理的牧草种植模式提供理论依据。试验选用我国中南部春播区推荐的作物品种大豆铁丰31和玉米强盛199,在旱作区域开展不同大豆玉... 定量化探索中国北方在平水年下,不同大豆玉米复合种植模式的种间竞争与种间互惠关系,以期为旱作条件下选择合理的牧草种植模式提供理论依据。试验选用我国中南部春播区推荐的作物品种大豆铁丰31和玉米强盛199,在旱作区域开展不同大豆玉米带状复合种植模式的大田栽培试验,采用完全随机区组设计4种大豆玉米带状复合种植模式,同时以大豆与玉米清种作为对照,测定不同种植模式下的生物量、邻体效应指数(RII),比较不同种植模式下大豆和玉米的互作关系。结果显示,大豆RII为-0.28~0.13,玉米RII为-0.28~0.12。在6行大豆3行玉米(S6M3)复合种植模式下,大豆和玉米的生物量较清种对照分别增加了28.95%和27.79%,且高于其他复合种植模式下作物生物量;大豆和玉米的RII分别为0.13和0.12,二者存在正相互作用。综上,在与试验区年降雨量相差不明显的旱作区域,选择S6M3复合种植模式有望提高青贮饲料产量。 展开更多
关键词 大豆玉米复合种植 生物量 邻体效应指数 旱作
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Estimation of biomass in wheat using random forest regression algorithm and remote sensing data 被引量:34
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作者 Li'ai Wang Xudong Zhou +2 位作者 Xinkai Zhu Zhaodi Dong Wenshan Guo 《The Crop Journal》 SCIE CAS CSCD 2016年第3期212-219,共8页
Wheat biomass can be estimated using appropriate spectral vegetation indices.However,the accuracy of estimation should be further improved for on-farm crop management.Previous studies focused on developing vegetation ... Wheat biomass can be estimated using appropriate spectral vegetation indices.However,the accuracy of estimation should be further improved for on-farm crop management.Previous studies focused on developing vegetation indices,however limited research exists on modeling algorithms.The emerging Random Forest(RF) machine-learning algorithm is regarded as one of the most precise prediction methods for regression modeling.The objectives of this study were to(1) investigate the applicability of the RF regression algorithm for remotely estimating wheat biomass,(2) test the performance of the RF regression model,and(3) compare the performance of the RF algorithm with support vector regression(SVR) and artificial neural network(ANN) machine-learning algorithms for wheat biomass estimation.Single HJ-CCD images of wheat from test sites in Jiangsu province were obtained during the jointing,booting,and anthesis stages of growth.Fifteen vegetation indices were calculated based on these images.In-situ wheat above-ground dry biomass was measured during the HJ-CCD data acquisition.The results showed that the RF model produced more accurate estimates of wheat biomass than the SVR and ANN models at each stage,and its robustness is as good as SVR but better than ANN.The RF algorithm provides a useful exploratory and predictive tool for estimating wheat biomass on a large scale in Southern China. 展开更多
关键词 Above-ground dry biomass TRITICUM AESTIVUM VEGETATION indices WHEAT
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Stand-level biomass models for predicting C stock for the main Spanish pine species 被引量:4
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作者 Ana Aguirre Miren del Río +1 位作者 Ricardo Ruiz-Peinado Sonia Condés 《Forest Ecosystems》 SCIE CSCD 2021年第2期387-402,共16页
Background:National and international institutions periodically demand information on forest indicators that are used for global reporting.Among other aspects,the carbon accumulated in the biomass of forest species mu... Background:National and international institutions periodically demand information on forest indicators that are used for global reporting.Among other aspects,the carbon accumulated in the biomass of forest species must be reported.For this purpose,one of the main sources of data is the National Forest Inventory(NFI),which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested indicators.Methods:Stand level biomass models,relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the Iberian Peninsula(Pinus sylvestris,Pinus pinea,Pinus halepensis,Pinus nigra and Pinus pinaster).The dependence of the model on aridity and/or mean tree size was explored,as well as the importance of including the stand form factor to correct model bias.Furthermore,the capability of the models to estimate forest carbon stocks,updated for a given year,was also analysed.Results:The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size,although the effect varied among the five pine species.Site humidity,measured using the Martonne aridity index,increased the biomass for a given volume in the cases of Pinus sylvestris,Pinus halepensis and Pinus nigra.Models that consider both mean tree size and stand form factor were more accurate and less biased than those that do not.The models developed allow carbon stocks in the main Iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg·ha^(-1).Conclusions:The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass models.The described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available. 展开更多
关键词 Martonne aridity index dry weight biomass Carbon stock National Forest Inventory Peninsular pine forest biomass expansion factor
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Above-ground Biomass Allocation in a Planted Forest in a Semi-arid Region of Northern Mongolia
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作者 Sukhbaatar Gerelbaatar Nachin Baatarbileg 《Journal of Agricultural Science and Technology(B)》 2013年第3期216-220,共5页
关键词 地上生物量 生物量分配 半干旱地区 种植园 内蒙古 森林 樟子松人工林 生态系统生产力
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Responses of Dry Bean to 2,4-D Ester Applied Preplant and Preemergence
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作者 Nader Soltani Christy Shropshire Peter H. Sikkema 《American Journal of Plant Sciences》 2019年第12期2170-2178,共9页
Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g&middot;ai&middot;ha-1 applied 14, 7 and 1 da... Six field studies were completed in Ontario (during 2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy bean to 2,4-D ester at 528 or 1056 g&middot;ai&middot;ha-1 applied 14, 7 and 1 day before seeding (PP) and 3 days after seeding (PRE). 2,4-D applied PP or PRE caused as much as 4%, 6%, 7% and 8% injury in adzuki, kidney, small red and navy (white) bean, respectively. There was an increase in bean injury as the preplant interval decreased. At 1 WAE, 2,4-D applied at 1056 g&middot;ai&middot;ha-1 14, 7 and 1 day PP and 3 days after seeding caused up to 6%, 10%, 18% and 5% visible bean injury, respectively. The level of injury decreased over time with minimal bean injury (0 to 3%) at 8 WAE. Bean stand counts were similar to the non-treated control with 2,4-D applied at various timings except at 1 day PP when 2,4-D at the 2X rate decreased bean stand 13%. There was up to 23% and 43% decrease in bean dry weight with 2,4-D applied PP at 528 and 1056 g&middot;ai&middot;ha-1 7 and 1 day PP, respectively. Bean height (6 WAE) was not affected by 2,4-D applied at various timings except at 1 day PP when 2,4-D (1056 g&middot;ai&middot;ha-1) decreased bean height 10%. Additionally, there was no effect of 2,4-D treatments on bean maturity or yield. Based on these results, the safest times to apply 2,4-D are 14 days before seeding or PRE. Injury was higher when 2,4-D was applied 7 and 1 day PP. Injury was lower in adzuki bean compared to kidney, small red or navy bean. 展开更多
关键词 BEAN STAND Crop Injury dry BEAN biomass PLANT Height PLANT Sensitivity Yield
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Fluidized Bed Superheated Steam Dryer for Bagasse: Effects of Particle Size Distribution
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作者 Luz Stella Polanco Vadim Kochergin Jose F. Alvarez 《Journal of Sustainable Bioenergy Systems》 2013年第4期265-271,共7页
Fluidized bed superheated steam drying is one of the technologies successfully applied to drying pulp in the sugar beet industry. It has the technological advantages of energy efficiency and safety (inert environment)... Fluidized bed superheated steam drying is one of the technologies successfully applied to drying pulp in the sugar beet industry. It has the technological advantages of energy efficiency and safety (inert environment) required for use in drying bagasse. A comparison of the particle size distribution of bagasse and beet pulp was evaluated in terms of fluidization. The size distribution of bagasse particles is from 2 to 10 times broader than the equivalent distribution of beet pulp particles. The mean particle size of the bagasse is 1/3 of the mean size of the beet pulp. Fluidization tests proved that bagasse fluidization is possible. It was found that beet pulp and bagasse particles clearly differ on shape and size distribution which in turn will affect the design of the ancillary equipment and the fluidization systems if sugarcane bagasse is to be dried using superheated steam technology. 展开更多
关键词 biomass BAGASSE dryING Particle Size Fluidized BED
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Effect of Lime and Phosphorus on Yield and Yield Components of Groundnut Varieties [Arachis hypogaea L.] on Acidic Soil in Nedjo District, Western Ethiopia
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作者 Askalu Dessalegn Nigussie Dechassa Lemma Wogi 《Agricultural Sciences》 2023年第12期1653-1674,共22页
Groundnut (Arachis hypogaea L.) is an important cash crop for smallholder farmers in western Ethiopia. However, the yield of the crop is very low mainly because of strong soil acidity and poor soil fertility managemen... Groundnut (Arachis hypogaea L.) is an important cash crop for smallholder farmers in western Ethiopia. However, the yield of the crop is very low mainly because of strong soil acidity and poor soil fertility management. A study conducted to evaluate the effect of lime and mineral phosphorus fertilizer on yield components and yield of groundnut. The treatments consisted of three phosphorus rates (0, 46 and 92 kg P<sub>2</sub>O<sub>5·</sub>ha<sup>-1</sup>), three lime rates (0, 6, and 11 ton lime·ha<sup>-1</sup>), and three groundnut varieties (local cultivar, Werer-961, and Werer-963) was laid-out as a randomized complete design in a factorial arrangement with three replications. The corresponding rates of phosphorus applied per pot of soil (7 kg) amounted to 0, 107 and 215 mg kg·soil<sup>-1</sup> and those of lime amounted to 0, 14, and 26 g kg·soil<sup>-1</sup>. The analysis of variance showed that phenological characters, yield, and yield components significantly affected by interaction of variety, phosphorus, and lime. The highest dry pod yield produced by Werer-963 (2 kg dry pod yield·pot<sup>-1</sup>) in response to the application 11 t·ha<sup>-1</sup> lime and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. However, Werer-961 produced medium (1.5 kg dry pod yield·pot<sup>-1</sup>) at 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> and the local cultivar produced minimum (1 kg dry pod yield·pot<sup>-1</sup>) at the application of 11 t·ha<sup>-1</sup> lime and 92 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup>. In terms of phosphorus yield efficiency index, Werer-963 was highly efficient (index of 1.71), and Werer-961 was moderately efficient (index of 0.6). However, the local cultivar was inefficient (index of 0.04). It is at, in acidic soil of the study area Werer-963 is the best to be cultivated with application of lime 11 t·ha<sup>-1</sup> and 46 kg P<sub>2</sub>O<sub>5</sub>·ha<sup>-1</sup> fertilizer, followed by Werer-961. The results of this pot experiment have revealed that farmers in the study area need to switch to cultivating the improved varieties of groundnut rather than local variety with the application of high rates of lime and moderate amounts of phosphorus. 展开更多
关键词 dry biomass Yield dry Pod Yield Harvest Index Yield Efficiency Index Hundred Seed Weight
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短期氮添加对高寒草地植物高度和生产力的影响
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作者 王娟 刘俊杰 +1 位作者 刘超 王勇 《新疆大学学报(自然科学版)(中英文)》 CAS 2023年第2期242-249,256,共9页
研究不同氮添加梯度和频次下草地生产力、植物高度、水分含量和干鲜比的变化趋势,利用样方调查法调查巴音布鲁克草原代表性物种,分析高寒草地常见植物高度、生产力和干鲜比比值.结果表明:该地区整体植物群落高度变化不显著,蔷薇科(Rosac... 研究不同氮添加梯度和频次下草地生产力、植物高度、水分含量和干鲜比的变化趋势,利用样方调查法调查巴音布鲁克草原代表性物种,分析高寒草地常见植物高度、生产力和干鲜比比值.结果表明:该地区整体植物群落高度变化不显著,蔷薇科(Rosaceae)植物高度受氮添加梯度和频次的影响较大,禾本科(Poaceae)植物高度在两种氮添加频次下影响显著.莓叶委陵菜(Potentilla fragarioides)、冰草(Agropyron cristatum)、羊茅(Festuca ovina)植物高度在两种氮添加频次下差异显著.不同氮添加梯度和频次对植物地上生产力影响显著,随氮添加梯度的提升植物地上生产力呈现出增加趋势,禾本科植物生产力受氮添加因素的影响显著,蔷薇科和豆科(Fabaceae)植物生产力变化不大.巴音布鲁克草地植物的含水量介于35.10%~45.87%,干鲜比介于54.13%~64.90%. 展开更多
关键词 氮添加 植物高度 地上生物量 高寒草地 干鲜比 水分含量
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臭氧污染对亚热带森林生产力和生物量的影响——以鼎湖山为例
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作者 王钦艺 黄玫 +2 位作者 王昭生 王绍强 李跃林 《生态学报》 CAS CSCD 北大核心 2023年第5期1832-1842,共11页
全球气候变化背景下,我国近地面臭氧浓度不断增加,已严重威胁到森林生态系统。但是,目前臭氧污染影响我国亚热带森林生物量的研究仍然具有较高的不确定性。本研究比较了不同模型和不同参数化方案评估的鼎湖山森林和林下草地生物量损失... 全球气候变化背景下,我国近地面臭氧浓度不断增加,已严重威胁到森林生态系统。但是,目前臭氧污染影响我国亚热带森林生物量的研究仍然具有较高的不确定性。本研究比较了不同模型和不同参数化方案评估的鼎湖山森林和林下草地生物量损失率的差别,比较了鼎湖山阔叶林和针叶林以及林下草地的生物量损失率与总初级生产力(GPP)损失率的一致性。2015—2016年臭氧污染造成的鼎湖山阔叶林生物量损失率为11.3%—11.69%,针叶林生物量损失率为3.97%—3.68%,草地生物量损失11.2%—14.6%;不同参数化方案估计的鼎湖山阔叶林的生物量损失率在9%—13%之间,针叶林的生物量损失率在3.68%—4.4%之间变化,草地在11.2%—14.6%之间。基于臭氧剂量响应关系模型估算的阔叶林GPP损失率为10%—12.6%,针叶林GPP损失率为1.81%—2.6%,草地GPP损失率为3.2%—3.3%。总的来看,鼎湖山阔叶林和针叶林的生物量和GPP损失具有较高的一致性,阔叶林生物量和GPP的损失率明显高于针叶林生物量和GPP的损失率。 展开更多
关键词 臭氧 亚热带森林 生物量 干沉降模型
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不同土壤和微量元素对车桑子幼苗生长的影响
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作者 王雪梅 闫帮国 +2 位作者 王梓丞 史亮涛 刘刚才 《热带亚热带植物学报》 CAS CSCD 北大核心 2023年第5期695-704,共10页
为了解微量元素对车桑子(Dodonaea viscosa)生长的作用,研究添加微量元素(硼B、铁Fe、锰Mn、锌Zn)对车桑子生长和叶绿素荧光特性的影响。结果表明,除Mn外,B、Zn和Fe均对车桑子的生长和叶绿素荧光参数有显著促进作用(P<0.05);且添加B... 为了解微量元素对车桑子(Dodonaea viscosa)生长的作用,研究添加微量元素(硼B、铁Fe、锰Mn、锌Zn)对车桑子生长和叶绿素荧光特性的影响。结果表明,除Mn外,B、Zn和Fe均对车桑子的生长和叶绿素荧光参数有显著促进作用(P<0.05);且添加B的车桑子具有更高的生物量积累,比对照显著提高了133.61%。微量元素与土壤类型对叶片磷(P)含量和叶片氮磷比(N/P)具有显著的交互作用(P<0.05),紫色土添加Zn、黄棕壤添加Fe均显著降低了叶片N/P。燥红土和黄棕壤上车桑子的株高、叶面积和生物量积累均高于紫色土,但紫色土和黄棕壤上车桑子的根冠比和叶片N/P显著高于燥红土(P<0.001)。这表明微量元素对干热河谷车桑子生长具有重要作用,在植被恢复过程中可通过添加B、Fe、Zn尤其是B来促进植物生长。 展开更多
关键词 土壤类型 微量元素 车桑子 干热河谷 生物量
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生物质储藏技术研究进展
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作者 胡玮麟 谭梦娇 +3 位作者 朱艺 张轩 李辉 杨海平 《综合智慧能源》 CAS 2023年第5期80-85,共6页
在全面响应“碳达峰”“碳中和”的背景下,需对典型可再生资源——生物质的利用与储藏进行研究。现有关于生物质直接储藏的研究大多借鉴的是堆肥、食品贮藏、秸秆青贮等技术的研究方法,对生物质在储藏阶段的温室气体排放不够重视。生物... 在全面响应“碳达峰”“碳中和”的背景下,需对典型可再生资源——生物质的利用与储藏进行研究。现有关于生物质直接储藏的研究大多借鉴的是堆肥、食品贮藏、秸秆青贮等技术的研究方法,对生物质在储藏阶段的温室气体排放不够重视。生物质储藏能够弥补原料采收、供应和需求之间的差异,是生物质供应链的核心环节。回顾了生物质储藏的概念、自发热与干物质损失机理,对比了生物质储藏技术与堆肥、厌氧消化、成型燃料储藏等传统技术。在此基础之上阐述了生物质储藏过程中产生温室气体的机理,并提出了减少干物质损失的新方法。在已有研究成果的基础上加大对储藏技术的研发投入,提高生物质储藏效率,可为生物质原料的绿色高效储藏提供依据。 展开更多
关键词 “双碳”目标 生物质 储藏 干物质损失 降解 温室气体排放
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喷施硼肥对藜麦生长发育及单株产量的影响
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作者 马琦琦 李丽君 +2 位作者 王斌 霍晓兰 刘平 《陕西农业科学》 2023年第12期62-69,共8页
随着藜麦在山西种植面积的不断扩大,研究喷施硼肥对生长在缺硼(B)土壤中藜麦生长发育及产量的影响尤为重要。本试验以3个品种藜麦(晋藜1号、晋藜2号、晋藜3号)为试验材料,进行盆栽试验。在拔节期,以叶面喷施方式对藜麦施用不同浓度的B肥... 随着藜麦在山西种植面积的不断扩大,研究喷施硼肥对生长在缺硼(B)土壤中藜麦生长发育及产量的影响尤为重要。本试验以3个品种藜麦(晋藜1号、晋藜2号、晋藜3号)为试验材料,进行盆栽试验。在拔节期,以叶面喷施方式对藜麦施用不同浓度的B肥2次,每盆50 ml/次。试验结果表明,施硼对藜麦生长发育有促进作用。当施硼浓度为0.3%时,3个品种藜麦株高均显著增加,较对照分别增加了16.34%、11.67%、14.57%;晋藜1号与晋藜3号茎粗显著增加,较对照分别增加10.44%和21.72%,而硼对晋藜2号茎粗影响不明显;3个品种藜麦叶片SPAD值显著增加,较对照分别增加33.72%、9.33%、17.77%;3个品种藜麦干物质累积量显著增加,较对照分别增加40.23%、14.10%、31.37%;3个品种藜麦单株粒重显著增加,较对照分别增加24.51%、45.33%、47.70%,提高了藜麦产量。试验范围内,随着施硼浓度的提高,3个品种藜麦的株高、茎粗、干物质累积量、SPAD值、单株粒重均高于对照。实际生产中,应选用0.3%的硼最为合适。 展开更多
关键词 藜麦 株高 茎粗 干物质累积量 SPAD值 单株粒重
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Development and Evaluation of an All Weather-Type Solar Drying House to Make for Wood Pellet Material
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作者 Kimio Kanayama Shinya Koga +1 位作者 Hiromu Baba Tomoyoshi Sugawara 《Open Journal of Applied Sciences》 2012年第3期153-162,共10页
To suppress the global environment pollutions, we tried to develop a new-type solar drying house by improving a typical agricultural green-house, so that an all weather-type solar drying house was invented ultimately.... To suppress the global environment pollutions, we tried to develop a new-type solar drying house by improving a typical agricultural green-house, so that an all weather-type solar drying house was invented ultimately. This house is capable to dry raw wood materials (Ogako) into suitable moisture content (Mc) to make a wood pellet. The all weather-type solar Ogako drying house is covered with a triple transparent film, and an open/close free-type shield sheet is spread along with house’s inner surface with a small space, which is opened when solar radiation is incident on the house in daytime and closed to prevent heat loss from the house while out of sun shining in night. Inside of the all weather-type solar Ogako drying house, there are four belt-conveyors over which four top radiation panels are hanged, and on which four Ogako agitators are touched, a turn-table, two hoppers, four small fans, and besides, a floor heating is molded in concrete floor. Also on the north wall outside the house, two insulated cylinders (chimney) are stood up vertically to exhaust inside moist air passively. Then, to make clearly the operation performance of the house, the drying tests for the proof examination were conducted nineteen times at first test site in Ashoro where is located east-central part of Hokkaido, Japan. As a result of the drying test for the proof examination, it was made clear that the all weather-type solar Ogako drying house is practically useful as a supplementary apparatus to produce the dried Ogako, and consequently to suppress CO2 exhaustion. 展开更多
关键词 Solar ENERGY and biomass ENERGY Agricultural Green-House Ogako drying HOUSE WOOD Powder (Ogako) WOOD PELLET Moisture Content (Mc) Decrease of Oil Consumption Suppression of CO2 EXHAUSTION
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田间老化生物质炭对黄土高原旱作农田土壤有机氮组分的影响
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作者 潘占东 蔡雪梅 +3 位作者 蔡立群 董博 武均 张仁陟 《植物营养与肥料学报》 CAS CSCD 北大核心 2023年第12期2219-2231,共13页
【目的】研究田间老化生物质炭对土壤有机氮组分及微生物生物量碳氮的影响,为生物质炭在陇中黄土高原地区培肥改良土壤、提高氮肥利用效率方面的应用提供科学依据。【方法】2015年在甘肃农业大学旱作农业综合试验站开展定位试验,试验包... 【目的】研究田间老化生物质炭对土壤有机氮组分及微生物生物量碳氮的影响,为生物质炭在陇中黄土高原地区培肥改良土壤、提高氮肥利用效率方面的应用提供科学依据。【方法】2015年在甘肃农业大学旱作农业综合试验站开展定位试验,试验包含6个玉米秸秆生物质炭添加量:0、10、20、30、40、50 t/hm^(2),依次记为CK、BC1、BC2、BC3、BC4、BC5处理。2020年小麦收获后(第5茬),调查了春小麦产量,采集0—5、5—10和10—30 cm土层土壤,用Bremner法测定有机氮组分及微生物生物量碳、氮含量。【结果】施用生物质炭5年后依然能显著提高春小麦产量,以BC3处理春小麦产量最高,较CK显著提高了24.76%。与CK相比,生物质炭处理土壤全氮(TN)和微生物生物量碳(MBC)分别显著增加6.55%~10.94%、68.63%~139.74%,微生物生物量碳氮比(BC/BN)增加10.60%~202.44%。有机氮各组分占比表现为:氨基酸态氮(AAN)>非酸解氮(AIN)>酸解铵态氮(AMN)>酸解未知态氮(UAN)>氨基糖态氮(ASN),分别占土壤全氮的27.46%~45.13%、15.47%~31.14%、19.00%~28.66%、1.59%~18.54%和2.76%~8.86%。其中三个酸解氮含量在5个生物质炭处理土壤中均表现为:AAN>AMN>ASN,BC2、BC3、BC4和BC5处理土壤AAN和ASN含量分别较CK显著提高17.58%~81.51%和43.60%~107.55%,BC2和BC3处理土壤AMN含量显著提高15.46%~28.95%。BC3处理土壤的酸解总氮(TAN)、AMN和ASN含量最高,AIN含量最低。【结论】土壤全氮及微生物生物量碳是影响有机氮组分差异的主要因素。10~50 t/hm^(2)施用量下,生物质炭均显著提高了土壤全氮及微生物生物量碳,施用生物质炭30 t/hm^(2)提高土壤酸解总氮、酸解铵态氮和氨基糖态氮含量的效果最显著,土壤供氮能力最强,春小麦产量最高。因此,在黄土高原旱作农业区,合理的生物质炭用量可长期提高土壤供氮能力。 展开更多
关键词 老化生物质炭 黄土高原 旱作农田 有机氮组分 微生物生物量碳氮
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不同除草剂对黄芪田杂草防除效果及黄芪生物量、药材产量的影响研究 被引量:1
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作者 李雪 尹大保 +2 位作者 刘致尧 王健 王俊杰 《畜牧与饲料科学》 2023年第3期89-95,共7页
[目的]研究不同除草剂对黄芪地上生物量积累、药材产量及杂草防除效果的影响。[方法]对1年生蒙古黄芪移栽苗选用5种苗后除草剂按照推荐使用浓度进行施药处理,5种农药分别为药草除1号(YCC)、灭草松(MCS)、烯草酮(XCT)、盖草能(GCN)、拿捕... [目的]研究不同除草剂对黄芪地上生物量积累、药材产量及杂草防除效果的影响。[方法]对1年生蒙古黄芪移栽苗选用5种苗后除草剂按照推荐使用浓度进行施药处理,5种农药分别为药草除1号(YCC)、灭草松(MCS)、烯草酮(XCT)、盖草能(GCN)、拿捕净(NBJ),以喷施清水为对照(CK)。每种施药处理3次重复,共18个小区。2021年6月初采用样方法统计各处理小区内杂草株数、鲜质量、干质量,于7月10日、8月10日、9月10日定期统计各处理小区蒙古黄芪地上生物量鲜重、干重,并测定当年11月采收季黄芪药材鲜重、干重。采用变异分析和单因素方差分析对统计数据进行分析。[结果]5种除草剂均表现出不同程度的杂草防除效果,其中,药草除1号处理组(YCC)杂草防效最好,株防效为77.81%,鲜质量防效为64.48%,干质量防效为80.81%。7、8、9月各除草剂处理组之间黄芪地上生物量鲜重、干重以及鲜干比之间无显著(P>0.05)差异;11月,药草除1号处理组(YCC)的黄芪药材产量鲜重和干重均显著(P<0.05)高于其他处理组。[结论]蒙古黄芪移栽田使用药草除1号进行杂草防除的效果较好,且对药材地上生物量、产量有明显的促进作用。 展开更多
关键词 除草剂 黄芪 生物量 鲜干比 杂草防效 产量
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市政污泥湿颗粒热干化动力学分析
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作者 孙国震 张伟 +4 位作者 叶佳璐 梁文政 常国璋 李杰 王翠苹 《山东科技大学学报(自然科学版)》 CAS 北大核心 2023年第6期66-74,共9页
将高湿污泥分别掺混木屑和核桃壳半焦调节湿度,掺混污泥造粒后进行湿颗粒热干化特性研究。分别通过热重分析仪与流化床进行层状干化和流化干化受热失水过程研究,分析了高湿污泥颗粒干化失水规律。结果表明,对于层状干化,3种颗粒干化过... 将高湿污泥分别掺混木屑和核桃壳半焦调节湿度,掺混污泥造粒后进行湿颗粒热干化特性研究。分别通过热重分析仪与流化床进行层状干化和流化干化受热失水过程研究,分析了高湿污泥颗粒干化失水规律。结果表明,对于层状干化,3种颗粒干化过程均可分为4个阶段,其中污泥掺混半焦失重最大(61.8%),失重速率最快(9.0%/min),但吸收热量也最多,层状干化的失重速率在一定温度范围内与Z-L-T方程所描述的三维扩散吻合;流化干化的热源温度对于污泥颗粒干化有较大影响,160℃时纯污泥的干化失重最多,300℃时污泥掺混半焦与掺混木屑颗粒的干化失重相近,均优于纯污泥颗粒,流化干化过程的失水速率遵循Modified Page动力学模型;污泥颗粒入炉含湿量相近时,流化干化较层状干化具有明显的优势,各污泥颗粒均快速失水,含水率降至5%~10%。 展开更多
关键词 高湿污泥 生物质 层状干化 流化干化 动力学模型
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