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91.
近年来,随着互联网平台的迅速发展,农业传感网络能促进农业向网络型转化;针对传统农业存在的资源交互性差、有效农业数据普及范围小、农业网络信息更新速度慢等问题,提出云平台下智慧农业传感网络的设计与实现;利用大数据环境搭建专项数据云平台,储存汇集优良农业网络数据资源;采用云采资源换算算法,对云端平台内的数据进行快速调取,进行双位动态影像空间设计;智能交互窗口模块分为资源检索、资源导航、农资互动、专家指导4个板块,智能交互窗口模块采用高速视频无损压制算法,能够保证传输流畅,同时采用片源压制减小片源体积;通过仿真实验测试证明,提出的云平台下智慧农业传感网络的设计各项数据优异,满足现代农业发展应用要求,为现代化网络型智慧农业的生产应用领域提供新的思路。 相似文献
92.
Tara Allohverdi Amar Kumar Mohanty Poritosh Roy Manjusri Misra 《Molecules (Basel, Switzerland)》2021,26(18)
In a time when climate change increases desertification and drought globally, novel and effective solutions are required in order to continue food production for the world’s increasing population. Synthetic fertilizers have been long used to improve the productivity of agricultural soils, part of which leaches into the environment and emits greenhouse gasses (GHG). Some fundamental challenges within agricultural practices include the improvement of water retention and microbiota in soils, as well as boosting the efficiency of fertilizers. Biochar is a nutrient rich material produced from biomass, gaining attention for soil amendment purposes, improving crop yields as well as for carbon sequestration. This study summarizes the potential benefits of biochar applications, placing emphasis on its application in the agricultural sector. It seems biochar used for soil amendment improves nutrient density of soils, water holding capacity, reduces fertilizer requirements, enhances soil microbiota, and increases crop yields. Additionally, biochar usage has many environmental benefits, economic benefits, and a potential role to play in carbon credit systems. Biochar (also known as biocarbon) may hold the answer to these fundamental requirements. 相似文献
93.
基于机载高光谱成像的柑橘产量预测模型研究 总被引:3,自引:0,他引:3
果树的隔年结果现象严重影响果园的果实产量和经济效益。选择受隔年结果现象影响较为严重的柑橘作为研究对象,运用机载高光谱成像仪在较早生长季节(2003年4、5、6月)获取柑橘果树的高光谱图像,利用偏最小二乘回归(PLS)确定基于高光谱图像数据的模型预测变量,建立柑橘产量的多元线性回归(MLR)和人工神经网络(ANN)预测模型。研究结果表明,利用5月份获得的高光谱图像建立的模型具有最优的产量预测效果, 而且PLS-MLR模型比PLS-ANN模型具有更好的稳定性和一致性。该研究结果为今后研制和开发基于高光谱成像技术的柑橘产量预测方法提供了重要的理论和技术基础。 相似文献
94.
95.
介绍了目前我国高等农林院校大学数学课程的开设情况,分析了大学数学系列课程的教学改革成果、现状以及存在的一些问题,同时对在高等农林院校中如何进行大学数学课程改革提出了若干建议和措施. 相似文献
96.
Masahiko Yoshimura Michael Dieckmann Pierre-Yves Dakas Raymonde Fonné-Pfister Claudio Screpanti Katrin Hermann Stefano Rendine Pierre Quinodoz Beyza Horoz Saron Catak Alain De Mesmaeker 《Helvetica chimica acta》2020,103(4):e2000017
Strigolactones are plant hormones, which play pivotal roles in plant growth and development with potential application in sustainable agriculture. Recently, zealactone 1a/b has been identified as the major strigolactone from the root exudates of corn. Although zealactone is a promising molecule affecting signaling in the rhizosphere as well as in planta, evaluating its biological activities has been hampered by its low natural abundance and its relative chemical instability. Herein, we present the total synthesis of zealactone 1a/b based on our studies employing a [2+2]-cycloaddition strategy and a chemoselective Baeyer-Villiger oxidation to forge the γ-butyrolactone fragment. Furthermore, we disclose the biological activities of zealactone 1a/b on corn and in soil in comparison with related synthetic analogues. 相似文献
97.
Nikola Mijailovic Andrea Nesler Michele Perazzolli Essaid Aït Barka Aziz Aziz 《Molecules (Basel, Switzerland)》2021,26(6)
Rare sugars are monosaccharides with a limited availability in the nature and almost unknown biological functions. The use of industrial enzymatic and microbial processes greatly reduced their production costs, making research on these molecules more accessible. Since then, the number of studies on their medical/clinical applications grew and rare sugars emerged as potential candidates to replace conventional sugars in human nutrition thanks to their beneficial health effects. More recently, the potential use of rare sugars in agriculture was also highlighted. However, overviews and critical evaluations on this topic are missing. This review aims to provide the current knowledge about the effects of rare sugars on the organisms of the farming ecosystem, with an emphasis on their mode of action and practical use as an innovative tool for sustainable agriculture. Some rare sugars can impact the plant growth and immune responses by affecting metabolic homeostasis and the hormonal signaling pathways. These properties could be used for the development of new herbicides, plant growth regulators and resistance inducers. Other rare sugars also showed antinutritional properties on some phytopathogens and biocidal activity against some plant pests, highlighting their promising potential for the development of new sustainable pesticides. Their low risk for human health also makes them safe and ecofriendly alternatives to agrochemicals. 相似文献
98.
Heldeney Rodrigues Sousa Idglan S Lima Lucas Matheus Lima Neris Albert Santos Silva Ariane Maria Silva Santos Nascimento Francisca Pereira Araújo Rafael Felippe Ratke Durcilene Alves Silva Josy Anteveli Osajima Leilson Rocha Bezerra Edson Cavalcanti Silva-Filho 《Molecules (Basel, Switzerland)》2021,26(9)
Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer–Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture. 相似文献
99.
It was investigated the phytotoxicity as well as the fate of dinobuton and dinobutonmethyl in bean and cucumber plants and in apple fruits. Dinobutonmethyl is more phytotoxic than dinobuton. Generally dinobuton and dinobutonmethyl behave similarly after application on the apple surface and also after treatment of the leaves of bean and cucumber plants. After 3–5 days only about 50% of the applied radioactivity were found on the surface of the systems. Probably dinobuton and dinobutonmethyl as well as dinoseb as hydrolysis product are able to leave the plant systems unchanged. 相似文献
100.