Agronomy research最新文献_第5页

Intra-annual height growth dynamics of Scots and lodgepole pines and its relationship with meteorological parameters in central Latvia. 拉脱维亚中部苏格兰松和黑松的年际高度增长动态及其与气象参数的关系。

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.002

Ā. Jansons, J. Dzenis, R. Matisons, Valters Samariks, B. Jansone

{"title":"Intra-annual height growth dynamics of Scots and lodgepole pines and its relationship with meteorological parameters in central Latvia.","authors":"Ā. Jansons, J. Dzenis, R. Matisons, Valters Samariks, B. Jansone","doi":"10.15159/AR.20.002","DOIUrl":"https://doi.org/10.15159/AR.20.002","url":null,"abstract":"The Scots pine (Pinus sylvestris L.) is the second-most widely used tree species in forestry in Latvia and is the only species used for afforestation on nutrient poor soils that cover considerable forest land in Latvia. Several studies have shown that, in such conditions, the lodgepole pine (Pinus contorta var. latifolia) may be more productive in terms of biomass and yield. It is important to consider climate change studies to assess the potential for a larger-scale use of the lodgepole pine in forestry. The aim was to assess the intra-annual height growth patterns of both species, the differences between them, and the influence of meteorological parameters on their height growth. Their height growth was monitored on a weekly basis in two sampling sites in central Latvia, and the height increment curves were described by Gompertz’s model. The height growth dynamics of individual trees and species differed notably, indicating the potential for the selection of the best-adapted genotypes. Our results indicate that the early onset of the active growth phase might be the most important factor determining the total height increment for both species. Temperature-related meteorological parameters were the only ones with a statistically significant influence on pines height growth and only when at least one of the variables were standardised prior to the analysis. A temperature increase had a slightly stronger positive effect on the growth of the lodgepole pine, indicating that it might be suitable for more intensive use in forestry under the climate change scenarios for Latvia.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"410-421"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66968144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Lean-inspired development work in agriculture: Implications for the work environment 农业中的精益开发工作:对工作环境的影响

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.043

K. Andersson, A. Rydberg, J. Eklund

引用次数: 1

Estimate of manure present in compost dairy barn systems for sizing of manure storage 估计堆肥牛棚系统中存在的粪便，以确定粪便储存的大小

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.105

F. A. Damasceno, J. Monge, J.A.C. Nascimento, R. R. Andrade, M. Barbari, J. Saraz, G. Ferraz

{"title":"Estimate of manure present in compost dairy barn systems for sizing of manure storage","authors":"F. A. Damasceno, J. Monge, J.A.C. Nascimento, R. R. Andrade, M. Barbari, J. Saraz, G. Ferraz","doi":"10.15159/AR.20.105","DOIUrl":"https://doi.org/10.15159/AR.20.105","url":null,"abstract":"Milk production is increasingly modernized as a result of the growing demand for food around the world. Improvements in livestock facilities are observed, with a large increase in the use of feedlot systems such as the Compost Dairy Barn. Increasing milk production in confinement systems has also raised concerns such as the management of wastes (water, faeces and urine) from the system, which has become one of the most important issues in the intensive dairy farms. The aim of this work was to estimate the amount of manure present in compost dairy barn systems in order to size the manure storage. The study was conducted at four compost dairy barns in southern Minas Gerais, Brazil. These compost barns had different bedding materials and dimensions. In each farm, data on milk yield and quality (daily production, fat and protein content), animal weight and amount of feed ingested by the animals were collected. Total-day manure delivered by the cows in the feeding alley and milking parlour was piled up together and weighed. Based on the results, it was observed that, in the compost dairy barns, only part of the total manure produced per day was delivered in the milking parlour (1.6 and 2.0%) and in the feed alley (27.6 to 49.3%). These results are very important for designers for the proper manure management system design of the dairy farms.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"1213-1219"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66969727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

New approach for recycling spare parts, components and assemblies. 回收备用零件、组件和组件的新方法。

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.141

V. Mitrofanovs, Ē. Geriņš, I. Boiko

{"title":"New approach for recycling spare parts, components and assemblies.","authors":"V. Mitrofanovs, Ē. Geriņš, I. Boiko","doi":"10.15159/AR.20.141","DOIUrl":"https://doi.org/10.15159/AR.20.141","url":null,"abstract":"Recycling and disposal are one of the most complicated topics in the lifecycle of a mechanism, especially in case of previous generations of machines that were designed without taking any care of post exploitation period. In the current work, the ‘feasibility points’ of recycling units, methods of recycling as well as pricing formation for recycling materials, reviewed and proposed by several world universities and scientific bureaus and applied by major world brands have been analysed. The general principles that should be rated as a basis when designing and creating new mechanisms, as well as the actions which we consider as a necessary supplement to the existing rules of the lifecycle of assemblies and which should be applied in practice, were introduced by authors in the ‘Management of parts and components for units and assemblies in mechanical engineering industry and its impact on the environment’. It was discovered that even modern assemblies, not to mention previous generations, are being designed without taking into consideration any possibilities of easy recycling the used materials. The number of components of mechanisms, which are being repaired as assemblies, is continuously increasing, while maintainability and repairability of separate parts is decreasing. Taking into account the state of the art in the field, the new approach for promoting the reusing natural resources and decreasing the harmful effects of obsolete components of mechanisms on the environment is proposed. Thus, using the fast-moving parts that in post operational period can be easily detailed by type of a material will ensure more efficient consumption of natural resources. Our research and developments significantly reduce the costs of recycling and these materials become competitive comparing to the new ones. Taking into account the state of the art in the field, the new approach for promoting the reusing natural resources and decreasing the harmful effects of obsolete components of mechanisms on the environment is proposed.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"923-930"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66970656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The spatio-temporal trend of rapeseed yields in Ukraine as a marker of agro-economic factors influence 乌克兰油菜籽产量的时空变化趋势作为农业经济因素影响的标志

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.119

A. Zymaroieva, O. Zhukov, T. Fedonyuk, T. Pinkina

{"title":"The spatio-temporal trend of rapeseed yields in Ukraine as a marker of agro-economic factors influence","authors":"A. Zymaroieva, O. Zhukov, T. Fedonyuk, T. Pinkina","doi":"10.15159/AR.20.119","DOIUrl":"https://doi.org/10.15159/AR.20.119","url":null,"abstract":"The paper demonstrates the applicability of several statistical methods to the analysis and interpretation of the average rapeseed yield data. It proves our hypothesis that the general trend of rapeseed yield variations in Ukraine during 1991–2017 occurred due to agro-economic and agro-technological factors, which are the determinants of the revealed general trend. The temporal trend of rapeseed yield in most administrative districts can be described by a fourth-degree polynomial, namely, its characteristic points enabled us to describe and interpret the dynamics of rapeseed yields. The absolute term of the polynomial shows the initial conditions of the process, and its mapping allows us to identify the areas with the most favorable soil-climatic conditions for the rapeseed cultivation. Indicators of the maximum rate of growth and decrease of yields are the markers of stability of agro-ecosystems to the external influences. Therefore, the mapping of the maximum rate of decline and increase of yields reveal areas in which yields respond rapidly (increasing / falling) to the changes in agro-economic and agro-technological conditions, as well as areas where yields are more stable and change gradually. Thus, the form of the yield trend is determined by the influence of agro-technological and agro-economic factors, whose contribution to the fluctuation in rapeseed yields varies from 53% to 90%.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"1584-1596"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66971054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

A control method for increasing the heat usage efficiency of nearly-zero-energy buildings with heat pumps 用热泵提高近零能耗建筑热利用效率的控制方法

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.032

H. Pihlap, A. Annuk, M. Lehtonen, S. Muiste, A. Tooming, Alo Allik

引用次数: 1

Research on energy efficiency of pneumatic cylinder for pneumatic vehicle motor. 气动汽车马达用气缸能效研究。

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.048

J. Rudzītis, M. Madissoo, M. Gailis, J. Kreicbergs

引用次数: 1

Sorghum dry biomass yield for solid bio-fuel production affected by different N-fertilization rates. 不同施氮量对固体生物燃料生产高粱干生物量产量的影响

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.072

D. Bartzialis, K. Giannoulis, E. Skoufogianni, A. Lavdis, G. Zalaoras, G. Charvalas, N. Danalatos

{"title":"Sorghum dry biomass yield for solid bio-fuel production affected by different N-fertilization rates.","authors":"D. Bartzialis, K. Giannoulis, E. Skoufogianni, A. Lavdis, G. Zalaoras, G. Charvalas, N. Danalatos","doi":"10.15159/AR.20.072","DOIUrl":"https://doi.org/10.15159/AR.20.072","url":null,"abstract":"The objective of this study was to examine the effect on the dry biomass yield of two dfferent sorghum hybrids (H1 and H2) under five different N-fertilization levels (0, 70, 140, 210 and 280 kg ha) in a soil which was formed by lacustrine deposits of Karla Lake and is characterized from the downward movement of calcium carbonate from the surface horizons due to leaching (Fluventic Xerochrept) during 2017. The results demonstrated a significant effect (P < 0.05) of fertilization only for one hybrid. Biomass yield ranged from 22.2 to 37.5 t ha. For both hybrids, sorghum accumulated a high amount of biomass in stems. Dry stem/total biomass ratio was rather constant throughout the different fertilization treatments achieving 81.6 and 77.5% for the first (H1) and the second hybrid (H2), respectively. The second hybrid (H2) had a higher percentage of leaf biomass (20.1 vs. 13.8%) than the first (H1), but lagged behind in seed production (2.4 vs. 4.6%). Biomass dry matter partitioning and total dry weight are important selection criteria for energy crops, due to different gross calorific value and ash content but also because of the different economic importance they may have e.g. the seed is also used as animal feed. The above high biomass yields of sorghum, confirming the high potential of this crop, should be taken into serious consideration regarding land use planning, but further investigation for the gross calorific value and the ash content is needed as well as biomass characteristics that are quite important in case to improve the combustion process.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"36 1","pages":"1147-1153"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66969297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Comparison of airflow homogeneity in compost dairy barns with different ventilation systems using the CFD model. 采用CFD模型比较不同通风系统的堆肥牛棚气流均匀性。

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.106

B. Fagundes, F. A. Damasceno, R. R. Andrade, J. Saraz, M. Barbari, F. Vega, J.A.C. Nascimento

{"title":"Comparison of airflow homogeneity in compost dairy barns with different ventilation systems using the CFD model.","authors":"B. Fagundes, F. A. Damasceno, R. R. Andrade, J. Saraz, M. Barbari, F. Vega, J.A.C. Nascimento","doi":"10.15159/AR.20.106","DOIUrl":"https://doi.org/10.15159/AR.20.106","url":null,"abstract":"In the pursuit of high milk productivity, producers are using confinement systems in order to improve performance and animal welfare. Among the housing systems, the Compost bedded-pack barns (CBP) stand out. In these barns a bedding area is provided inside, where cows move freely. Generally this area is covered with carbon source material (such as sawdust or fine dry wood shavings) which together with manure, thanks a regular mechanically stirring, ensures the aerobic composting process. The ventilation in these facilities has the function of dehumidifying the air, improving the air quality, drying the bedding, improving the thermal comfort conditions of the confined animals. This work aimed at validating a computational model using Computational Fluid Dynamics (CFD) to determine the best homogeneity of airflows generated by different forced ventilation systems used in CBP barns. Two CBP barns were compared with different ventilation systems: high volume low speed (HVLS) and low volume high-speed (LVHS) fans. The results showed that the proposed model was satisfactory to predict the flows generated by both types of fans. It was concluded that the use of HVLS fans produced a more homogeneous airflow when compared to LVHS fans. The use of mechanical ventilation in tropical conditions is necessary for the proper functioning of the system. In this study, the systems used promoted the increase in air speed to levels close to adequate.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"788-796"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66969754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

The sustainable reuse of compost from a new type of olive mill pomace in replacing peat for potted olive tree 一种新型橄榄磨渣堆肥的可持续再利用，以取代盆栽橄榄树的泥炭

Agronomy research Pub Date : 2020-01-01 DOI: 10.15159/AR.20.129

L. Regni, D. Pezzolla, G. Gigliotti, P. Proietti

{"title":"The sustainable reuse of compost from a new type of olive mill pomace in replacing peat for potted olive tree","authors":"L. Regni, D. Pezzolla, G. Gigliotti, P. Proietti","doi":"10.15159/AR.20.129","DOIUrl":"https://doi.org/10.15159/AR.20.129","url":null,"abstract":"The attention for the replacement of peat in growing substrates is increasing due to its environmental and economic advantages. The aim of the present work was to evaluate the impact of peat substitution by new type olive mill pomace and its compost on the vegetative activity of potted olive trees. A new type of humid pomace (hP) derived from an innovative two phase extraction system and its derived compost (C-hP) are used as total or partial (50% vol/vol) replacement of peat in olive growing substrate. The main chemical characteristics (moisture, water extractable organic carbon, total nitrogen, C/N ratio and electrical conductivity) of the hP and C-hP were measured. In order to evaluate the effects of the peat substitution on the plants vegetative activity, measurements of mortality, plant height, leaf net photosynthesis and plant growth (through final destructive measurements) were carried out. The use of hP resulted in a significant increase of the salinity of the substrate. The water extractable organic carbon concentration was higher in all substrates where peat was ewplaced and in particular when C-hP was used. The total replacement of peat with hP caused 100% mortality of the plants while C-hP can substitute peat up to 50% without causing a significative reduction of the final plant growth.","PeriodicalId":7924,"journal":{"name":"Agronomy research","volume":"18 1","pages":"1444-1454"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66970904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4