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The Salt Reduction and Yield Increase Effects of Smashing Ridging Transforming Saline-alkali Land and Its Development Prospects 被引量:3
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作者 Wei Benhui Shen Zhangyou +5 位作者 Zhou Jia Zhou Lingzhi Gan Xiuqin Lao Chengying Li Yanying Hu Po 《Meteorological and Environmental Research》 CAS 2018年第4期112-115,120,共5页
Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2... Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2015 -2016. The results showed, in severe saline-alkali soil of Xin-jiang ,after growing cotton by smashing ridging, total salt in soil decreased by 31.31 %, cotton production increased by 48.80%, and salinity level declined from severe to moderate; in mild saline-alkali soil of Shaanxi, after growing summer corn by smashing ridging, total salt in soil decreased by 42.37%, corn yield increased by 34.83%, salinity degree changed from mild desalination to normal farmland ; in Ningxia, Inner Mongolia 7 Gansu ,Jilin, Henan, Hebei, and so on, smashing ridging tillage practice in different types of saline-alkali land was conducted ; according to the salt reduction and yield increase effects of saline-alkali land after smashing ridging, the development prospect of smashing ridging technique in improvement and application of saline-alkali land was proposed. 展开更多
关键词 Smashing ridging Saline-alkali land IMPROVEMENT Salt reduction Yield increase PROSPECT
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Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions 被引量:4
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作者 Jingui Wei Qiang Chai +5 位作者 Wen Yin Hong Fan Yao Guo Falong Hu Zhilong Fan QimingWang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期122-140,共19页
The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.H... The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas. 展开更多
关键词 water and N reduction plant density MAIZE grain yield N uptake compensation effect
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Empirical Research on Quality Improvement and Effect Increase of Rural Tourist Destination Under the Strategic Background of Rural Revitalization: A Case Study of Xishan District, Kunming City, Yunnan Province
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作者 MA Ying ZHANG Chaoxuan 《Journal of Landscape Research》 2019年第1期90-94,共5页
As one of important channels in rural revitalization and development, rural tourism obtains a lot of remarkable achievements in rural development. However, relatively single product and homogenized development model m... As one of important channels in rural revitalization and development, rural tourism obtains a lot of remarkable achievements in rural development. However, relatively single product and homogenized development model make competition gradually intensify, and many once glorious rural tourist destinations gradually decline. Xishan District of Kunming City of Yunnan Province is taken as research object in this paper. Via literature research, field survey and depth interview, development process, status quo and existing problems of its rural tourism are deeply explored. Based on above research results, development idea, strategy and countermeasure for quality improvement and effect increase of traditional rural tourism destination are proposed, and cooperative development, mutual benefit and win-win are taken as the ultimate development goals. 展开更多
关键词 RURAL REVITALIZATION strategy RURAL tourism DESTINATION Quality improvement and effect increase Development path
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Effects of Full-Element Bio-Organic Fertilizer on Growth,Yield,and Rhizosphere Soil Nutrients of Pepper
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作者 CHEN Hai-rong HUANG Jun +4 位作者 WANG Bin HUANG Bin-bin TAN Shi-yong LIU Qing-shu GUO Zhao-hui 《Agricultural Science & Technology》 CAS 2024年第3期38-43,共6页
A field experiment was conducted to evaluate the effects of self-developed full-element bio-organic fertilizer on the growth,yield,and rhizosphere soil nutrients of pepper.Four treatments were designed,including full-... A field experiment was conducted to evaluate the effects of self-developed full-element bio-organic fertilizer on the growth,yield,and rhizosphere soil nutrients of pepper.Four treatments were designed,including full-element bio-organic fertilizer+conventional fertilizer reduced by 50%(T1),inactivated full-element bio-organic fertilizer+conventional fertilizer reduced by 50%(T2),conventional fertilizer(T3),and no fertilizer(CK).The results showed that T1 significantly increased the plant height,crown width,fruit number per plant,and yield of pepper.T1 had higher pH value,total nitrogen,total phosphorus,total potassium,available nitrogen,available phosphorus,and available potassium in the rhizosphere soil than T3 and CK,and it had higher available phosphorus and available potassium than T2.The disease index of bacterial wilt in T1 was 21.74,which was 10.37,20.19,and 35.48 lower than T2,T3,and CK,respectively.The control effect of T1 reached 56.71%.The above results indicated that whole bio-organic fertilizer promoted the growth to improve the yield and benefit of pepper.Moreover,the fertilizer activated soil nutrients to improve soil fertility and reduced soil-borne diseases.Therefore,the full-element bio-organic fertilizer can be promoted in the pepper fields with continuous cropping obstacles. 展开更多
关键词 PEPPER Full-element bio-organic fertilizer Disease resistance Yield increase
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A novel Effective Panicle Number per Plant 4 haplotype enhances grain yield by coordinating panicle number and grain number in rice
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作者 Yun Wang Xiaoqian Wang +6 位作者 Laiyuan Zhai Sundus Zafar Congcong Shen Shuangbing Zhu Kai Chen Yun Wang Jianlong Xu 《The Crop Journal》 SCIE CSCD 2024年第1期202-212,共11页
Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-... Increasing effective panicle number per plant(EPN)is one approach to increase yield potential in rice.However,molecular mechanisms underlying EPN remain unclear.In this study,we integrated mapbased cloning and genome-wide association analysis to identify the EPN4 gene,which is allelic to NARROW LEAF1(NAL1).Overexpression lines containing the Teqing allele(TQ)of EPN4 had significantly increased EPN.NIL-EPN4^(TQ) in japonica(geng)cultivar Lemont(LT)exhibited significantly improved EPN but decreased grain number and flag leaf size relative to LT.Haplotype analysis indicated that accessions with EPN4-1 had medium EPN,medium grain number,and medium grain weight,but had the highest grain yield among seven haplotypes,indicating that EPN4-1 is an elite haplotype of EPN4 for positive coordination of the three components of grain yield.Furthermore,accessions carrying the combination of EPN4-1 and haplotype GNP1-6 of GNP1 for grain number per panicle showed higher grain yield than those with other allele combinations.Therefore,pyramiding of EPN4-1 and GNP1-6 could be a preferred approach to obtain high yield potential in breeding. 展开更多
关键词 RICE effective panicle number per plant Grain number per panicle HAPLOTYPE Grain yield potential
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Residual Effects of Phosphate Amendments on Rainfed Rice (Oryza sativa L.) Nutrition and Soil Properties in Three Agroecological Zones of Côte d’Ivoire
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作者 Affi Jeanne Bongoua-Devisme Wondouet Hippolyte Kpan +3 位作者 Pla Kouassi Adou Franck Michaël Lemonou Bahan Konan-Kan Hippolith Kouadio Anselme Kan Louis Koko 《Open Journal of Soil Science》 2024年第10期606-634,共29页
A study was conducted in Côte d’Ivoire to assess the after-effect of phosphate amendments on rice yields and soil properties. Eight types of amendments, composed of Moroccan phosphate rock (PRM) and triple super... A study was conducted in Côte d’Ivoire to assess the after-effect of phosphate amendments on rice yields and soil properties. Eight types of amendments, composed of Moroccan phosphate rock (PRM) and triple superphosphate were tested in three agroecological zones over three consecutive years of cultivation. This study revealed that the application of Moroccan phosphate rock (PRM) and/or triple superphosphate (TSP) did not significantly affect soil cation exchange capacity (CEC) and organic carbon (Corg) content. However, there was a negative residual effect of PRM-rich treatments on soil pH and K and N content, but the impact varies depending on the characteristics of the soils studied. Furthermore, nutrient losses, notably nitrogen from −17.5 to −267.7 kg/ha and potassium (−0.1 to 0.7 kg/ha), were observed in all treatments. Only phosphorus showed a positive balance of +49.56 to +52 kg/ha in PRM-rich treatments. Treatment T3, composed of 80% RPM and 20% TSP, was the most effective in all zones, with a relative increase in grain yields of over 100% compared to the control. These results suggest that the input of natural phosphate rock can significantly improve rice yields and soil properties in the studied agroecological zones in Côte d’Ivoire. 展开更多
关键词 Phosphate Amendment Moroccan Phosphate Rock Triple Superphosphate Yield After-effect NUTRITION Crop Balance Cote d’Ivoire
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The Effects of Increasing Production of Endophytes Phomopsis B3 on Rice 被引量:18
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作者 戴传超 袁志林 +2 位作者 杨启银 史青山 李霞 《Agricultural Science & Technology》 CAS 2008年第1期39-42,48,共5页
After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seed... After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seedling showed that leaf age,the number of green leaves,the number of tiller of individual plant and the weight of per 100 fresh plants in microbial inoculum treatment group increased 0.11,0.12 ,0. 03 and 2.6 g respectively compared with those of control group. 20 days after transplanting, increased tiller number in microbial inoculum treatment group was 55 500 hm^2 more than that in control group. 30 days after transplanting, tiller number in microbial inoculum treatment group was 42 000 hm^2 more than that in control group. In harvest season, the yield ,weight of I 0130 grain and seed-setting rate increased 300 kg/hm2, 0. 7 g and 0. 23% respectively compared with these in control group. The result of preliminary study demonstrated that microbial inoculum confected by endophytes phomopsis B3 could increase the number of strong seedling and yield. 展开更多
关键词 ENDOPHYTES PHOMOPSIS RICE Yield increasing Strong seedling
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The Effect of the Novel "light fertilizer" on the Environment Factor in High Tunnel and Growth of Brassica Chinensis 被引量:6
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作者 李文秀 周宁琳 +5 位作者 陈园园 王佳 朱晓玲 王振江 徐磊 冯伟民 《Agricultural Science & Technology》 CAS 2014年第12期2245-2248,共4页
[Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel.... [Objective] The aim was to study the properties of novel "light fertilizer", photo-conversion film, in order to evaluate its effect on the environmental factors and morphogenetic process of crops in the high tunnel. [Method] Photo-conversion film and Iongevous anti-dropping film were compared in terms of light, air and soil temperature utilizing the Facilities of leafy agriculture high tunnel intelligent monitoring system. Verifying the results by farmland experiment. [Result] Photo- conversion film indeed improved the light quality of high tunnel compared with the Iongevous anti- dripping film. The air and soil temperature was raised several degrees. Results of farmland experiment show that the average value of brassica chinensis fresh weight increased 19.15% compared to the control. [Conclusion] Photo-conversion film promotes more crop growth than Iongevous anti-dropping film due to improvement of light quality, air and soil temperature. 展开更多
关键词 Photo-conversion film Environmental factors Light quality WARMING Light quality Yield increase Brassica chinensis
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Initial Exploration on Effect of Saline-alkali Land Rebuilding and Utilization by Fenlong Cultivation 被引量:2
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作者 韦本辉 申章佑 +6 位作者 周佳 甘秀芹 劳承英 周灵芝 刘斌 胡泊 李艳英 《Agricultural Science & Technology》 CAS 2017年第12期2396-2400,共5页
In order to explore the effect of Fenlong cultivation in rebuilding and uti- lization of saline-alkali land, the Fenlong tillage machine and Fenlong technology were invented and put into tests in the saline-alkali lan... In order to explore the effect of Fenlong cultivation in rebuilding and uti- lization of saline-alkali land, the Fenlong tillage machine and Fenlong technology were invented and put into tests in the saline-alkali land from 2015-2016 in Xinjiang Autonomous Region and Shaanxi province, respectively. The results showed that in Xinjiang, the total salt content in the heavy saline-alkali soil decreased by 31.31% after one season of cotton planting using Fenlong, while cotton yield increased by 48.80%, and the soil salinity level was fallen from "severe" to "moderate" level. In Shaanxi, the total salt content in decreased by 42.73% after planting summer corn summer corn the mild saline-alkali land using Fenlong cultivation, while the corn yield increased by 34.83%, and the soil salinity degree was changed from "mild de- salination" to "normal farmland". At last, the paper provided the mechanism and reasons for desalination in soil and yield increase by Fenlong cultivation. 展开更多
关键词 Fenlong cultivation Saline-alkali land DESALINATION Yield increase PROSPECT
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Effects of Slow Release Fertilizer on the Yield and Nutrient Use Efficiency of Carnation and Its Environmental Protection Effect 被引量:4
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作者 杜彩艳 段宗颜 +1 位作者 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第4期571-575,共5页
[Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyl... [Objective] The aim was to study the effects of slow release fertilizer on the yield,economic benefit and nutrient use efficiency of carnation and environmental pollution.[Method] Taking carnation(Dianthus caryophyllus)as research object,the application effect and environmental protection effect of slow release fertilizer on carnation were discussed through field plot test.[Result] The main agronomic characters of carnation improved after the application of slow release fertilizer;compared with Conv-F treatment,the yield of carnation with slow release fertilizer increased by 18.67%-20.83%,and its economic benefit increased by 105 500 yuan/hm2,while the ratio of output to input improved by 74.29%;under the same NPK ratio and nutrient amount,the yield,economic benefit and ratio of output to input of carnation after the application of slow release fertilizer increased by 2.11%,14 800 yuan and 16.2%,respectively;besides,the application of slow release fertilizer improved the nutrient use efficiency of carnation,and N,P and K nutrient use efficiency in Opt-F-0.7% treatment increased by 13.88%,8.57% and 30.14% compared with Conv-F treatment.[Conclusion] Slow release fertilizer could not only reduce the waste of fertilizer resources and improve fertilizer use efficiency but also decrease the pollution caused by nutrient loss,which had important practical significance for protecting ecological environment and promoting the sustainable development of agriculture. 展开更多
关键词 Slow release fertilizer CARNATION YIELD Nutrient use efficiency Environmental protection effect
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Detailed Routing Algorithm with Optical Proximity Effects Constraint 被引量:1
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作者 周强 蔡懿慈 +1 位作者 张为 洪先龙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第2期189-195,共7页
We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential... We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential routing. The routing algorithm is based on constructed force directed Steiner tree routing to enhance routing efficien- cy. Experimental results on industrial benchmark circuits show that the presented routing algorithm can obtain much improvement considering optical effects short runtime. 展开更多
关键词 optical proximity effect detailed routing Steiner tree YIELD
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Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China 被引量:1
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作者 孙成韬 张小祥 《Agricultural Science & Technology》 CAS 2015年第10期2104-2106,共3页
The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved aroun... The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What's more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects. 展开更多
关键词 MAIZE Utra-fine powder Seed-coating agent Germination potential YIELD Spring sowing area Application effect
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Effects of Key Agricultural Measures of Mechanized Direct Seeding Technology on Rapeseed Yield in Chengdu Plain
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作者 姜心禄 代昌富 郑家国 《Agricultural Science & Technology》 CAS 2014年第9期1543-1549,共7页
Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measure... Mechanized direct sowing of rapeseed is a labor-saving and highly-efficient culture technique. In order to explore high-yield cultivation techniques suitable for Chengdu Plain, effects of several key agronomic measures', such as sowing date, density and N fertilizers, on development and yield formation were studied by strip and split plot experiment of three factors. The research showed that optimal condi- tions for direct seeding technology can be achieved provided with scientific sowing date, density and appropriate N fertilizers, and the research showed that rapeseed yield reached the peak at 320 g/m2, when sowing date was on September 3th, sow- ing density was 30 plant/m2, and nitrogen fertilizer was 27 g/m2. 展开更多
关键词 RAPESEED Mechanized direct sowing Agricultural measures Yield characters: effects
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Effects of “3414” Fertilization Effect Test on the Yield and Economic Benefit of Sagittaria sagittifolia 被引量:1
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作者 张驰 高美萍 +4 位作者 莫志欢 江文 韦绍龙 何芳练 颜梅新 《Agricultural Science & Technology》 CAS 2017年第6期1076-1079,1101,共5页
[Objective] To screen the optimal fertilizer formula, and to lay foundation for the research on special fertilizer for Sagittaria sagittifolia production. [Method] Based on the "3414" fertilization design, the yield... [Objective] To screen the optimal fertilizer formula, and to lay foundation for the research on special fertilizer for Sagittaria sagittifolia production. [Method] Based on the "3414" fertilization design, the yield of S. sagittifolia in each treatment was determined, and the effects of N, P and K treatments on the yield and eco- nomic benefit of S. sagittifolia were investigated, obtaining the optimal fertilizer appli- cation ratio. [Result] N, P and K had relatively good effects on the yield of S. sagittifolia. Treatment of N2P2K3 showed the optimal fertilizer application ratio, with the yield of 18 397.80 kg/hm2, yield increasing rate of 104.77%, and net income in- crease of 80 317.35 Yuan/hm2. N fertilizer had the greatest impacts on the yield of S. sagittifolia, followed with K fertilizer; while P fertilizer showed the poorest impacts. [Conclusion] To achieve the highest yield of S. sagittifolia, the fertilizer application was as follows: N of 446.70 kg/hm2, P20 of 568.10 kg/hm2, K2O of 534.90 kg/hm2, when the highest yield was 18 612.75 kg/hm2. Fertilizer application for the optimal economic benefit was N of 420.60 kg/hm2, P2O5 of 70.50 kg/hm2, K2O of 492.15 kg/hm2, when the optimal yield was 18 579.00 kg/hm2. 展开更多
关键词 Sagittaria sagittifolia "3414" fertilization effect test YIELD Economic ben- efit
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Effects of Subsoiling on Soil Moisture Under No-Tillage for Two Years 被引量:32
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作者 QIN Hong-ling GAO Wang-sheng +4 位作者 MA Yue-cun MA Li YIN Chun-mei CHEN Zhe CHEN Chun-lan 《Agricultural Sciences in China》 CAS CSCD 2008年第1期88-95,共8页
In order to improve the water use efficiency under conservation tillage, the effects of subsoiling on soil moisture under notillage were studied. An experiment of 40 cm subsoiling in a field kept under no-tillage for ... In order to improve the water use efficiency under conservation tillage, the effects of subsoiling on soil moisture under notillage were studied. An experiment of 40 cm subsoiling in a field kept under no-tillage for 2 years was operated from 2005 to 2006. Based on the data of the soil moisture and crop yield, the physical basis of subsoiling for water conservation and yield increase was analyzed. The results showed that the soil water storage under subsoiling, from the soil surface to a depth of 100 cm was more than that under no-tillage for the growth season. In the 0-100 cm soil depth, the soil moisture in 50-100 cm depth under subsoiling was more compared with no-tillage, which increased when it's drought and decreased when it's rainy with the increase in soil depth. Compared with no-tillage, subsoiling could reduce the water consumption of oats in the 0-50 cm depth and increase the water consumption in the 50-100 cm depth. Also, subsoiling increased the yield by 18.29% and the water use efficiency by 16.8% in a two-year average. The effects of subsoiling on water conservation and yield increase were affected by precipitation, and a well-proportioned rainfall was better to increase yield and water use efficiency. Meanwhile, subsoiling decreased bulk density, which increased with the available precipitation. Subsoiling under no-tillage is the effective rotation tillage to contain more soil moisture and improve water use efficiency in ecotone of North China. 展开更多
关键词 NO-TILLAGE SUBSOILING water conservation yield increasing
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Competition-density effect of tree organs in Acacia auriculiformis stands 被引量:3
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作者 Huifang Feng Li Xue 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期891-898,共8页
The competition-density (C-D) effects for mean mass for tree, stem, branch and leaf were analyzed in Acacia auriculiformis stands. Mean tree mass-density and mean organ mass-density were well explained by the C-D equa... The competition-density (C-D) effects for mean mass for tree, stem, branch and leaf were analyzed in Acacia auriculiformis stands. Mean tree mass-density and mean organ mass-density were well explained by the C-D equation of tree and the C-D equation of tree organ, respectively. An equation describing the relationship between mean leaf area u and density was formulated that fit the u-data well. The relationship between mean tree mass w and the ratio of each organ to mean tree mass (wo/ w) was examined. With increasing w, the stem mass ratio wS/w increased, whereas the branch mass ratio wB/w and the leaf mass ratio wL/w decreased. The yield difference between the lowest-density stand and the high-density stand became greater with stand growth. However, the yield of the mid-density stand was slightly lower than the yield of the high-density stand during the experimental period. To produce the most desirable combination of demanding individual-tree size and relative high stem yield, the mid-density is recommended as proper planting density for future management of A. auriculiformis stands. 展开更多
关键词 ACACIA auriculiformis C-D effect Leaf area Ratio of ORGAN MASS to TREE MASS TREE ORGAN Stand yield
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Influence of chemical reaction on heat and mass transfer of non-Newtonian fluid with yield stress by free convection from vertical surface in porous medium considering Soret effect 被引量:2
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作者 F. S. IBRAHIM F. M. HADY +1 位作者 S. M. ABDEL-GAIED M. R. EID 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第6期675-684,共10页
The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of ... The effect of chemical reaction on free convection heat and mass transfer for a non-Newtonian power law fluid over a vertical flat plate embedded in a fluid-saturated porous medium has been studied in the presence of the yield stress and the Soret effect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless form by similarity transformations, and the resulting system of equations is solved by a finite difference method. The results are preSented and discussed for concentration profiles, as well as the Nusselt number and the Sherwood number for various values of the parameters, which govern the problem. The results obtained show that the flow field is influenced appreciably by the presence of the chemical reaction parameter γ the order of.the chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω. 展开更多
关键词 non-Newtonian fluid free convection chemical reaction yield stress Soret effect
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Coupling Effect of Water and Fertilizer on Soybean Yield and Nutrient Absorption 被引量:2
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作者 HAO Li ZU Wei +2 位作者 SUN Cong-shu LEI Shu-xia LIU Li-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期105-114,共10页
Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertili... Soybean cultivar Bei 92-28 was tested in this experiment in 2000 to study the coupling effect of water and ferilizer on soybean yield.The results showed that the effect of irrigation varied among the levels of fertilizer application,and vice versa;pods per plant,seeds per pod.and 100-seed weight had positive correlations with soybean yield,but the degrees of correlations of different treatments were various;LAI and dry matter accumulation could be significantly increased when watered and applied fertilizer with different levels,but high fertilizer application treatment didn't obtain the highest yield;watering could increase the absolute absorption amount of N,P,K in seeds,but the accumulation rates were various. 展开更多
关键词 coupling effect WATER FERTILIZER soybean yield
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Experimental investigation of rigid confinement effects of radial strain on dynamic mechanical properties and failure modes of concrete 被引量:4
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作者 Pengfei Liu Xiaoping Zhou Qihu Qian 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期939-951,共13页
In this study,to confirm the effect of confining pressure on dynamic mechanical behavior and failure modes of concrete,a split Hopkinson pressure bar dynamic loading device was utilized to perform dynamic compressive ... In this study,to confirm the effect of confining pressure on dynamic mechanical behavior and failure modes of concrete,a split Hopkinson pressure bar dynamic loading device was utilized to perform dynamic compressive experiments under confined and unconfined conditions.The confining pressure was achieved by applying a lateral metal sleeve on the testing specimen which was loaded in the axial direction.The experimental results prove that dynamic peak axial stress,dynamic peak lateral stress,and peak axial strain of concrete are strongly sensitive to the strain rate under confined conditions.Moreover,the failure patterns are significantly affected by the stress-loading rate and confining pressure.Concrete shows stronger strain rate effects under an unconfined condition than that under a confined condition.More cracks are created in concrete subjected to uniaxial dynamic compression at a higher strain rate,which can be explained by a thermal-activated mechanism.By contrast,crack generation is prevented by confinement.Fitting formulas of the dynamic peak stress and dynamic peak axial strain are established by considering strain rate effects(50–250 s-1)as well as the dynamic confining increase factor(DIFc). 展开更多
关键词 Strain rate effect Multiaxial loading Dynamic peak axial stress Thermo-activated mechanism Dynamic increase factor
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Squeeze-Strengthening Effect of Silicone Oil-based Magnetorheological Fluid 被引量:2
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作者 刘新华 CHEN Qingqing +2 位作者 LIU Hao WANG Zhongbin ZHAO Huadong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期523-527,共5页
In order to study the squeeze-strengthening effect of silicone oil-based magnetorheological fluid (MRF), theoretical basis of disc squeezing brake was presented and a squeezing braking characteristics test-bed for M... In order to study the squeeze-strengthening effect of silicone oil-based magnetorheological fluid (MRF), theoretical basis of disc squeezing brake was presented and a squeezing braking characteristics test-bed for MRF was designed. Moreover, relevant experiments were carded out and the relationship between squeezing pressure and braking torque was proposed. Experiments results showed that the yield stress of MRF improved linearly with the increasing of external squeezing pressure and the braking torque increased three times when external squeezing pressure achieved 2 MPa. 展开更多
关键词 silicone oil-based magnetorheological fluid squeeze-strengthening effect yield stress braking characteristic
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