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1.
本文概略综述了近年来世界争论的“地球危机”问题。由于人类的活动,大气中二氧化碳等增加,气候恶化,地球升温,导致一系列重大自然灾害,严重地威协着人类。本文特对地震灾害进行了分析,温室效应对地球表面的升温,虽不至于直接影响到地震的孕育和发生,但是观测事实表明,环境因子太阳活动和气象与地震之间存在某种联系,对地震的发生常常起有调制和触发的作用,大气变化和太阳活动会影响到地震发生的频度和强度。为配合“国际减灾十年”活动,本文亦讨论了对策问题。  相似文献   
2.
稀土肥料在日光温室栽培草莓上的应用研究   总被引:3,自引:0,他引:3  
张西华  杨敏 《河南科学》1998,16(4):489-493
探讨了不同浓度的稀土肥料,分别用于日光温室栽培草莓(Fragariaananassa)的浸根及根外追肥,结果表明:定植时用200-300mg/kg浓度浸根;生长旺盛期、初花期、盛花期用300-400mg/kg浓度喷施,对草莓具有显著的增产效果。  相似文献   
3.
温室模糊控制系统设计   总被引:1,自引:0,他引:1  
针对温室环境控制的特点,介绍了温室控制系统的硬件组成,重点介绍了温度和相对湿度的模糊控制推理机制,给出了执行机构的模糊控制规则.测试结果表明了本控制方案是有效的.  相似文献   
4.
地源热泵在育种/育苗温室中的应用实验研究   总被引:2,自引:0,他引:2  
介绍了利用地源热泵技术为育种/育苗温室供暖,对温室进行温度调节.采用地源热泵技术利用浅层地能作为温室采暖热源.利用地源热泵技术,充分发挥浅层地能的效能,从地下土壤中获取能量作为温室采暖系统的基本负荷,满足温室加温时的供热需求,热泵机组采用中温热泵,末端采用地下盘管供热或风机盘管供暖风,可以快捷、方便的调节育种/育苗温室内的温度、湿度.取消原来的燃煤锅炉,降低燃煤能耗、较少污染物的排放.  相似文献   
5.
Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface water. Moreover, a higher rate of decomposition than primary production (photosynthesis) may lead to a shift of their function from being a sink of carbon to a source. This review paper assesses the potential response of natural wetlands (peatlands) and constructed wetlands to climate change in terms of gas emission and nutrients release. In addition, the impact of key climatic factors such as temperature and water availability on wetlands has been reviewed. The authors identified the methodological gaps and weaknesses in the literature and then introduced a new framework for conducting a comprehensive mesocosm experiment to address the existing gaps in literature to support future climate change research on wetland ecosystems. In the future, higher temperatures resulting in drought might shift the role of both constructed wetland and peatland from a sink to a source of carbon. However, higher temperatures accompanied by more precipitation can promote photosynthesis to a degree that might exceed the respiration and maintain the carbon sink role of the wetland. There might be a critical water level at which the wetland can preserve most of its services. In order to find that level, a study of the key factors of climate change and their interactions using an appropriate experimental method is necessary. Some contradictory results of past experiments can be associated with different methodologies, designs, time periods, climates, and natural variability. Hence a long-term simulation of climate change for wetlands according to the proposed framework is recommended. This framework provides relatively more accurate and realistic simulations, valid comparative results, comprehensive understanding and supports coordination between researchers. This can help to find a sustainable management strategy for wetlands to be resilient to climate change.  相似文献   
6.
邵鸿翔 《科技信息》2010,(19):I0064-I0064,I0102
本文介绍了基于AD590温度传感器和电阻式湿度传感器设计的四点温度检测控制电路,通过对大棚四个位置温湿度信息的提取转化为电信号,然后与要求温湿度参数设定的参考值进行比较,进而综合处理个点数据,实现对大棚温湿度的控制。  相似文献   
7.
优良野生地被植物唐古特莸扦插育苗技术研究   总被引:1,自引:0,他引:1  
唐古特莸是观赏价值较高的优良野生地被植物。本文针对唐古特莸温室扦插育苗,开展其不同基质及不同时期育苗试验。通过试验选择适合其快速繁殖的扦插基质及扦插时间。  相似文献   
8.
本文主要介绍白粉虱在西昌市大棚蔬菜蕃茄、黄瓜、豆类上的发生情况和特点,对白粉虱的防治进行了天敌和药剂试验,筛选出科学合理的综合防治措施。  相似文献   
9.
Climate change is identified as a major threat to wetlands. Altered hydrology and rising temperature can change the biogeochemistry and function of a wetland to the degree that some important services might be turned into disservices. This means that they will, for example, no longer provide a water purification service and adversely they may start to decompose and release nutrients to the surface water. Moreover, a higher rate of decomposition than primary production (photosynthesis) may lead to a shift of their function from being a sink of carbon to a source. This review paper assesses the potential response of natural wetlands (peatlands) and constructed wetlands to climate change in terms of gas emission and nutrients release. In addition, the impact of key climatic factors such as temperature and water availability on wetlands has been reviewed. The authors identified the methodological gaps and weaknesses in the literature and then introduced a new framework for conducting a comprehensive mesocosm experiment to address the existing gaps in literature to support future climate change research on wetland ecosystems. In the future, higher temperatures resulting in drought might shift the role of both constructed wetland and peatland from a sink to a source of carbon. However, higher temperatures accompanied by more precipitation can promote photosynthesis to a degree that might exceed the respiration and maintain the carbon sink role of the wetland. There might be a critical water level at which the wetland can preserve most of its services. In order to find that level, a study of the key factors of climate change and their interactions using an appropriate experimental method is necessary. Some contradictory results of past experiments can be associated with different methodologies, designs, time periods, climates, and natural variability. Hence a long-term simulation of climate change for wetlands according to the proposed framework is recommended. This framework provides relatively more accurate and realistic simulations, valid comparative results, comprehensive understanding and supports coordination between researchers. This can help to find a sustainable management strategy for wetlands to be resilient to climate change.  相似文献   
10.
如何应对气候变化是我国各级决策部门目前正在思考解决的问题。依据现实数据对我国温室气体排放的区域特征有个具体明确的认识。通过搜集我国能源及其它统计数据,参考IPCC提供的温室气体排放量报告方法,对2009年我国30个省份温室气体排放量的数据进行收集和测算,从区域的角度对排放总量、人均排放量、排放强度等指标进行分析。研究发现我国东中西部二氧化碳排放差异明显,规律明显。  相似文献   
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