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1.
根据黑龙江省大豆生产的实际情况,构建大豆生产预警指标体系,确定黑龙江省大豆生产的预警流程。通过确定黑龙江省大豆生产预警警限和警度,编制扩散指数,进行大豆生产景气指数预警分析,建立大豆生产趋势外推预测模型和先行指标预警模型,对黑龙江省大豆生产进行中短期预测预警。结合黑龙江省大豆生产安全的多种预警结果,确定和验证了黑龙江省大豆生产的近期状态。 相似文献
2.
利用加法模型将黑龙江省大豆生产增长的波动因素和长期趋势因素分离,确定大豆生产的波动指数,并根据波动指数的特点对大豆产量波动成因进行分析.根据分析结果划分了黑龙江省大豆生产增长的周期,分析了各个周期的特点,对黑龙江省大豆产量的趋势进行了定性预测,结果与实际相吻合. 相似文献
3.
从大豆产业在农业结构调整中的地位和作用出发,分析了大豆作为黑龙江省优势农产品所具有的特色与潜力;论述了大豆生产现状及主要发展趋势;提出了黑龙江省加快发展大豆产业、促进大豆生产机械化快速发展的设想。 相似文献
4.
大豆作为黑龙江省重要的粮食作物之一,对于促进农业种植业结构调整和增加农民收入具有重要意义。通过分析黑龙江省大豆机械化生产的现状,在深入研究存在问题的基础上,提出了发展大豆机械化生产的对策与建议。 相似文献
5.
发展鲜食大豆生产能够增加豆农收益,同时有利于农业种植结构的调整。近年来,黑龙江省随着鲜食大豆种植面积的不断扩大,对其全程机械化要求越来越紧迫。阐述了国内外及黑龙江省鲜食大豆生产机械化现状,并提出了鲜食大豆产业发展建议。 相似文献
6.
为了全面贯彻实施“黑龙江省耕地保护条例” ,切实加强农业基础建设 ,推动质量效益型农业的持续发展 ,根据黑龙江省机械化旱作农业试点市(县)宁安市的调查 ,他们从改革传统耕作方式 ,推广应用机械化旱作农业技术入手 ,经过几年的试验示范 ,摸索总结出机械化旱作农业高产耕作栽培制度 ,取得了明显成效 ,现就在旱作农业区实施机械化高产耕作栽培制度谈如下意见 :一、实施机械化旱作农业耕作栽培制度的目的机械化旱作农业高产耕作栽培制度就是在农业生产中主要通过机械生产方式 ,应用机械化旱作农业综合技术 ,用最低的成本、消耗最少的土壤肥… 相似文献
7.
随着种植大豆玉米效益的变化,黑龙江省垄作区种植结构也相应进行了调整。因此,根据玉米、大豆种植比例及生长需求,研究轮作轮耕制度及对应的机械化作业工艺与规范对地区农业生产及农业机械化发展具有重要意义。在充分调研和查阅大量文献的基础上,以构建黑龙江省土壤合理耕层结构,保证大豆、玉米生产需求为目标,筛选和凝炼了适合目前种植结构的大豆-玉米轮作方式,并结合大豆、玉米收后茬地特点及后茬作物生长需求,确定该区域不同轮作制度对应的机械化耕整地技术与模式,并以此为基础,研究确定与轮作耕作制度相应的大豆、玉米生产机械化作业工艺过程及规范。本研究旨在为推进黑龙江省垄作区大豆玉米生产机械化生产水平提供依据,为提高农业效益、促进种植结构调整提供技术基础。 相似文献
8.
通过对我国大豆生产现状进行分析,指出大豆的生产机械化是必然趋势,并详细介绍了黑龙江省推广的“垄三”栽培等比较成熟的大豆种植机械化技术。 相似文献
9.
在黑龙江省的农业生产过程中,履带拖拉机起着重要的作用,在各市县被广泛地应用。在过去几年里,黑龙江省农业机械化工作的重点是机械化旱作农业推广,建立了以机械深松为主体的,翻、松、耙相结合的土壤耕作制度,取得了良好的抗干旱效果,农业获得了增产增收,这说明在未来天气干旱形势越来越严重的自然情况下,履带拖拉机将在未来的机械化旱作农业生产中,仍将长时期地发挥其重要的建设性作用。 相似文献
10.
阐述了黑龙江省旱作农业的形成及发展;介绍了目前正在全省实施的几项主要旱作技术;提出了加速旱作农业技术的有关措施。 相似文献
11.
Adoption of a new technology, such as irrigation, is a complex phenomenon. Several factors of economic and social nature contribute to the farm-level decisions affecting adoption. In this study, the role played by attitudes of potential adopters towards irrigation and its subsequent adoption on their farm unit was estimated. Two models were estimated, one incorporating only adopters' socio-economic characteristics, and the other, only their attitudes towards irrigation. Results suggest that adopters' attitude, particularly with respect to economic and environmental effects of irrigation, were significant determinants of their decision to proceed with adoption of irrigation, and have a role to play in adoption of irrigation over and above that explained by socio-economic characteristics. In particular, these results suggest that negative perceptions with respect to economics of irrigation and those related to its detrimental impacts on environmental quality, particularly through soil salinity, may be significant deterrents for adoption of irrigation. The study suggests that planning of large scale water development projects, particularly those involving irrigation, must be cognizant of attitudes of potential adopters. Furthermore, during the planning stages, more attention should be paid to the development of proper educational programs, as well as extension packages, to ensure that potential adopters formulate correct attitudes towards the new technology. 相似文献
12.
数学作为一门基础性学科,在学生的各个学习阶段都起到了不可替代的作用,在工科院校中数学教学的重要性更是升到了一个新的高度。通过数学的学习,可以培养学生的应用能力和探究思维,通过对数学知识的学习和灵活运用,学生的综合能力会得到系统性的提高。对于数学的教学工作,应当做到有针对性、有目标,在教学工作中,充分做到对症下药、有的放矢,让学生通过对数学的学习,提高自身的综合能力,更好地为社会建设贡献力量。 相似文献
13.
Agricultural ecosystems and their associated business and government systems are diverse and varied. They range from farms, to input supply businesses, to marketing and government policy systems, among others. These systems are dynamic and responsive to fluctuations in climate. Skill in climate prediction offers considerable opportunities to managers via its potential to realise system improvements (i.e. increased food production and profit and/or reduced risks). Realising these opportunities, however, is not straightforward as the forecasting skill is imperfect and approaches to applying the existing skill to management issues have not been developed and tested extensively. While there has been much written about impacts of climate variability, there has been relatively little done in relation to applying knowledge of climate predictions to modify actions ahead of likely impacts. However, a considerable body of effort in various parts of the world is now being focused on this issue of applying climate predictions to improve agricultural systems. In this paper, we outline the basis for climate prediction, with emphasis on the El Niño-Southern Oscillation phenomenon, and catalogue experiences at field, national and global scales in applying climate predictions to agriculture. These diverse experiences are synthesised to derive general lessons about approaches to applying climate prediction in agriculture. The case studies have been selected to represent a diversity of agricultural systems and scales of operation. They also represent the on-going activities of some of the key research and development groups in this field around the world. The case studies include applications at field/farm scale to dryland cropping systems in Australia, Zimbabwe, and Argentina. This spectrum covers resource-rich and resource-poor farming with motivations ranging from profit to food security. At national and global scale we consider possible applications of climate prediction in commodity forecasting (wheat in Australia) and examine implications on global wheat trade and price associated with global consequences of climate prediction. In cataloguing these experiences we note some general lessons. Foremost is the value of an interdisciplinary systems approach in connecting disciplinary knowledge in a manner most suited to decision-makers. This approach often includes scenario analysis based on simulation with credible models as a key aspect of the learning process. Interaction among researchers, analysts and decision-makers is vital in the development of effective applications — all of the players learn. Issues associated with balance between information demand and supply as well as appreciation of awareness limitations of decision-makers, analysts, and scientists are highlighted. It is argued that understanding and communicating decision risks is one of the keys to successful applications of climate prediction. We consider that advances of the future will be made by better connecting agricultural scientists and practitioners with the science of climate prediction. Professions involved in decision making must take a proactive role in the development of climate forecasts if the design and use of climate predictions are to reach their full potential. 相似文献
14.
分析了四川简阳地区砂岩和土壤中的水分运动特性和砂岩中储存的水分对土壤水分补给量的多少。对当地的砂岩和土壤进行了水分特征曲线的测定试验、入渗试验和蒸发试验,并采用研究中常用模型对试验结果进行了拟合,通过对拟合结果的分析,得出了当地土壤和砂岩的水分特性,总结出了该地区表面土层在缺水时水分很容易被下部砂岩层补给,砂岩中的水分是作物利用的重要水资源的结论。这对于充分利用当地水资源,合理确定类似地质条件地区灌溉定额,解决无灌溉条件丘陵区作物缺水问题,实现农业节水灌溉有一定的参考价值。 相似文献
15.
Pesticides degrade principally through biodegradation processes, whereas antibiotics kill microorganisms or inhibit their growth in soils and thus may affect the fate of pesticides. In this study, the impact of antibiotics on the degradation of atrazine in a sandy soil is investigated in lysimeters over a ninety-day period. Four treatments, monensin, narasin, salinomycin and non-antibiotic, were assigned in triplicate to twelve PVC lysimeters. Both soil and leachate samples were collected and analyzed at predetermined time intervals. In all treatments, atrazine was found to leach down through the soil profiles with the concentration level decreasing with depth, and only trace amounts of atrazine were found in the leachate. However, the statistical analysis of the results showed that all the three antibiotic treatments yielded a significantly slower dissipation of the atrazine level as compared to the non-antibiotic treatment; the mass balance analysis indicated an increased half-life of atrazine in the presence of antibiotics. 相似文献
16.
对饮料中的柠檬黄含量进行了测定和不确定度分析,通过对各影响因素的不确定度评定,试验重复性对饮料中合成着色剂的测量结果不确定度的影响最大,其次是样品处理回收率和标准曲线拟合引入的不确定度对试验结果也有较大的影响。结果表明:饮料中柠檬黄的含量为(103.5?3.5)mgkg,k=2。 相似文献
17.
Targeted sampling of water was performed in streams, the river mouth, and the municipal drinking-water tap in the vicinity of San Francisco, South Leyte, Philippines. Samples were processed on site and transported back to Sweden for analysis by gas chromatography mass spectrometry to identify and quantify the pesticides commonly used in the area. Collaborations were initiated with employees at the local Department of Agriculture and Municipal Disaster Coordinating Council to learn more about the rice cultivation in this area and times for spraying. Detectable levels of pesticides λ-cyhalothrin, cypermethrin and deltamethrin (0.0005-1.4 μg/L) were found in representative water samples. In 47% of samples the detected levels exceeded the recommended limit values for pesticides in surface water according to Swedish guidelines (Swedish Chemicals Agency, 2008). The analysis of samples taken at the river mouth revealed measurable levels of λ-cyhalothrin and cypermethrin, which means that residues of pesticides applied to rice paddy fields were shown to end up at the river mouth. The success of the sampling and analysis methods was confirmed by the data which was in accordance with the expected effect of dilution from day to day. Variable levels of insecticides in the river and all the way down to the sea may have adverse health effects on people using the water and on the aquatic environment, including sensitive coral reefs. This situation is applicable not only to the Philippines, but also to the whole of Southeast Asia, with approximately 70% of their human population living in coastal areas. As Southeast Asia encompasses approximately 34% of the world's coral reefs and between a quarter and a third of the world's mangroves, as well as the global biodiversity triangle formed by the Malay Peninsula, the Philippines, and New Guinea, the need to reduce the impacts of marine pollution in this region is of great importance. 相似文献
18.
为明确北京东南郊灌区表层土壤和农作物多氯联苯(PCBs)含量和污染水平以及人体健康风险,2015年在该灌区采集了20个土壤样品和28个作物样品,利用气相色谱-质谱联用仪分析了样品中7大类PCBs含量。研究结果表明,灌区表层土壤PCBs质量比为ND(低于检出限)到0.711 776μg/kg,均值为0.43μg/kg,总体上土壤PCBs含量随污灌历史年限增加而增加。本研究区表层土壤PCBs含量处于较低水平,土壤未受到PCBs污染且其生态风险概率均小于10%。灌区采集的冬小麦籽粒、大葱、茄子、梨、白薯、芥蓝PCBs含量均低于实验检出限,未检出;夏玉米籽粒、菜心和油菜PCBs总量分别为0.17~0.47μg/kg、1.63μg/kg和5.91μg/kg。不同污灌历史年限并未显著影响夏玉米籽粒PCBs含量。本研究区农产品PCBs含量处于较低水平,均低于美国卫生及公共服务部建议限量。采集的土壤和农产品样品仅四氯联苯含量高于实验检出限,能检测出;一氯联苯到三氯联苯和五氯联苯到七氯联苯均低于实验检出限,未检出。本研究中成人和儿童PCBs致癌风险分别为8.49×10-7和4.66×10-7,非致癌风险分别为1.41×10-1和3.88×10-1,均低于US EPA规定限值,说明PCBs未对人群产生明显的健康危害。致癌危害和非致癌危害均以口-作物(玉米和蔬菜)为主,其对人体健康所造成的风险占总个人年风险的比例分别为99.79%~99.95%和99.81%~99.94%。 相似文献
19.
沈阳市既是重工业城市,也是农业大市,发展现代农业必须依靠科技进步。在介绍沈阳市农业发展现状及农业科技条件的基础上,探讨科技进步在沈阳农业发展中的重要作用,并根据沈阳市的实际情况展望今后科技进步的发展方向,为加快沈阳市的农业发展提供理论参考。 相似文献
20.
针对野生刺五加叶片中黄酮含量的测量方法繁琐、时间较长及需破坏叶片等问题,提出了一种基于高光谱技术对不同时段的刺五加叶片中黄酮含量的估算模型。首先,分析提取地域、年龄、长势相近的20株刺五加叶片光谱特征,通过对叶片进行烘干、磨粉及利用紫外分光光度计等化学方法测得叶片中黄酮的真实含量,并选择4种预处理互相结合、比较的方式,判断出最优预处理模型;通过SPA与PCA算法的结合,选择出较明显的特征波段,通过MatLab2018a将特征波段的反射率分别与40组预测集验证相关性后,再分别选取预测值和20组实测值与BP神经网络、支持向量机进行模型建立。实验结果表明:利用BP神经网络建立的模型的校正集决定系数Rc2分别为0.8649、0.7976、0.8485,支持向量机建立的模型的校正集决定系数Rc2分别为0.7526、0.7742、0.7243,证明SNV和1 Der结合的预处理方式与BP神经网络所构建的模型效果最好。研究为高光谱技术对刺五加叶片中黄酮的反演提供了有力的支持,也会提高工业和药用采摘的效率及刺五加的利用价值。 相似文献
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