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41.
农药防治是茶树病虫害综合防治的重要组成部分,其在病虫害突发或爆发时具有快速高效的防治优势。茶树叶片表面具有亲水性,常量施药会造成茶叶农残超标、生态环境破坏等问题,实现茶树减量施药是减少茶叶农残的有效手段。系统综述了茶树生物特性、茶树病虫害预测诊断及防治方法、茶树植保机械及施药技术,强调提高茶树低容量喷雾的农药有效利用率是实现茶树减量施药的关键。针对目前茶园地面工况复杂及农药利用率低的问题,本文从低容量仿形喷雾机、茶树病虫害喷雾决策及智能终端等六个方面提出茶树病虫害施药技术及装备的研究建议,指出低量化、精准化及智能化是未来茶树植保喷雾机械及施药技术的发展方向。  相似文献   
42.
Headwater streams play a major role for provision of ecosystem services, e.g. drinking water. We investigated a high-altitude headwater catchment of the Kharaa River (including 41 1st-order rivers) to understand the impact of land cover (especially forest cover), environment and human usage on runoff, chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid, sparsely populated region of Mongolia. To verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality, we investigated 105 sampling sites, 37 of them at intermittent stream sections without water flow. Discharge was positively impacted by land cover types steppe, grassland and forest and negatively by shrubland, forest burnt by wild fires (indicating a reduction of permafrost) and slope. Water quality was affected by altitude, longitude and latitude, shrub growth and water temperature. Shannon diversity of macroinvertebrates was driven by water temperature, iron content of the water, flow velocity, and subbasin size (adjusted R2 = 0.54). Sample plots clustered in three groups that differed in water chemistry, macroinvertebrate diversity, species composition and bio-indicators. Our study confirms that steppes and grasslands have a higher contribution to runoff than forests, forest cover has a positive impact on water quality, and diversity of macroinvertebrates is higher in sites with less nutrients and pollutants. The excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved.  相似文献   
43.
以上海知识产权(专利信息)公共服务平台检索系统作为统计源,借助专利情报分析方法,对中国番茄的专利申请量、布局、技术研究重点、申请人情况、主要申请人的研究方向等方面进行分析,揭示中国番茄领域专利技术的分布规律及特征,探究中国番茄领域技术创新能力与技术水平,从而为番茄领域的技术研究提供参考依据。  相似文献   
44.
Laser land leveling has been increasingly adopted in the irrigated rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system in the state of Haryana (India), located in the north-western Indo-Gangetic Plains. Still, many farmers have applied it to only a fraction of their land. In this study, we used data collected from 621 farm households in Haryana and applied a double-hurdle model for assessing the factors that determine the adoption and intensity of laser-leveling technology. The results show that large land holders are more likely to laser level their farm land; however, we found a negative association between land holdings and the proportion of laser-leveled land. Information about technology through farmer-to-farmer communication and through private traders, participation in agricultural training and membership in local agricultural institutions increased both the likelihood and the intensity of adoption. Our findings call for a closer collaboration among the various stakeholders, specifically to promote farmer-to-farmer communication through increased participation in local institutions and increase the rate of adoption of laser leveling technology.  相似文献   
45.
This study was carried out to better understand non-adoption of improved varieties of potato (Solanum tuberosum) and associated technologies by smallholder farmers in Chencha, Ethiopia. Data were collected through a survey (n = 47) and in-depth interviews (n = 20). It shows how wealth status was a factor of major importance. Most wealthy and some medium-wealthy farmers adopted improved potato varieties and many of the improved production practices; they had access to seed, associated knowledge and support, and sufficient resources that were necessary to apply the improved practices. Non-adoption was common among many medium-wealthy and most poor farmers: they lacked—next to access to the technologies and knowledge—cash, land, and labor. Results indicated the need to rethink research and intervention efforts. Next to paying attention to differences in the access to technology and the related knowledge, there is a need to consider the variation in technology needs, supporting microcredit services, and room to experiment. As a result, different combinations of improved production practices may be adopted.  相似文献   
46.
为了明确海南山区耕地土壤养分空间分布特征,为热带山区耕地土壤养分管理提供思路。以海南五指山市耕地为研究对象,采用野外调查、采样和室内分析相结合的方法,阐述土壤养分现状,探讨其土壤养分分布规律。结果表明:五指山耕地土壤总体呈酸性,其pH值为5.1;土壤有机质、有效磷、速效钾和中量元素(钙、镁、硫)含量均为中等或偏下水平,土壤有效铜和有效锌含量较为丰富。五指山耕地土壤酸化和养分含量分布不均主要与气候、母质分布和施肥不平衡有关。  相似文献   
47.
随着社会经济的发展及农业劳动力的转移,韩国水稻种植方式发生了转型。从上世纪70年代末期开始,韩国水稻机插秧比例快速上升,手插秧比例下降,到90年代基本实现了水稻种植的机械化;省工节本的直播稻产量受不确定因素影响较大,且稻米品质不如机插秧和手插秧,其种植面积出现了波动,现只占韩国水稻种植面积的4%左右。本文介绍了韩国水稻机插秧、湿润直播和旱直播技术的作业流程。  相似文献   
48.
The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits.  相似文献   
49.
长武塬区苹果园和农田相互转换的深层土壤水环境效应   总被引:1,自引:0,他引:1  
研究长武塬区苹果园和农田相互转换后0~1 000 cm土壤含水量特征,分析了苹果园土壤干燥化和苹果园转换为农田后土壤水分的恢复效应。结果表明:2、7、17、23、29 a苹果园200~1 000 cm的平均土壤含水量分别为22.8%、21.4%、16.8%、15.4%、14.9%。500~1 000 cm土层中,29 a苹果园平均土壤含水量(14.5%)高于23 a的果园(13.3%);17~29 a的苹果园均表现为轻度干燥化;基于苹果园和农田转换后土壤水分变化情况估算,苹果园最大种植年限为21 a。苹果园转换为农田1、5、10 a后,农田200~1 000 cm土层土壤含水量分别为:15.3%、15.7%和16.2%,恢复到土壤稳定湿度以上的土层厚度分别为140 cm(1 a)、220 cm(5 a)和400 cm(10 a)。  相似文献   
50.
生产农作物绿色食品是农业的发展方向,也是可持续发展的必然要求,是世界范围都要引起 重视的普遍课题,我国更需迫切重视。使用一般的无公害杀虫剂是不能生产出绿色食品的,而目前病 虫害绿色防控技术还不成熟,现在可用于绿色食品生产的高效无毒的杀虫剂在我国已首先研究出来 了,当前缺少的仅是农产品市场完备的农药残留检测机制,解决这个瓶颈问题可给绿色食品创造存在 的空间,从而实现农业绿色产业大发展,这一天的到来已为期不远。  相似文献   
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