Optimizing the Irrigation Scheduling Strategy and the Water Use Efficiency in Steppe and Irrigated Crop Production Ecosystems in the Northwestern China

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不同节水措施对水田生态环境的影响研究

通过大田试验,研究了水稻浅水灌溉、浅湿灌溉和覆膜灌溉对生态环境的影响机理。结果表明,相对于其它2种节水措施,覆膜可以提高土壤温度,降低空气湿度,减少渗漏和棵间蒸发以及温室气体CH4和N2O的排放量,可控制杂草的生长和节水增产,从而促进作物有效生长、早熟;可有效控制病虫害、草害;提高灌水生产率、经济效益和生态环境效益。3种节水措施,覆膜效果最佳,浅湿灌溉次之,浅水灌溉最差。     

农田灌溉的马尔可夫决策规划模型

本文应用离散时间的马尔可夫决策规划(MDP)的原理和方法,建立了农田灌溉的MDP模型。同时,给出了求解(择优)的算法,并对一个简化的例子进行了实际求解。最后,讨论了模型的进一步发展。     

灌溉灰漠土春麦氮磷肥用量及其比例的研究

氮磷化肥配合施用对麦具有交互作用;交互作用大小随氨磷用量及比例而变化;氮磷用量及其比例适宜的组合交互作用值大,增产率最高。试验表明,灌耕灰漠上春麦适宜的氮磷用量及比例,氮(N)每亩10—15kg/亩、磷(P_2O_5)5～7.5kg,以氮(N)磷每亩(P_2O_5)比为1:0.5时经济效益较好。     

水利建设工程投标报价技巧与策略之研究

文章分析了水利工程投标过程中常见的问题和不规范现象，结合工作实际，对投标过程中招标文件研究、投标环境调查、投标决策等主要环节要做的工作进行了分析研究。归纳出几种针对不同情况进行投标报价的技巧和策略，为承包商提高中标率具有一定的现实指导意义。     

农村水资源自动化量测系统

针对我国目前农村水资源量测和管理水平较低，农村用水系统效率低下的问题，介绍农村水资源自动化量测系统的研制和应用。该系统应用先进的电子量测技术、计算技术及多项专利技术，采用最新研制的新型流速旋浆传感器、多功能智能流速仪和流速流向仪同步测量大型农业灌区的渠道流速与流量。该系统在祁东县曹口堰示范区水库灌区的应用表明，渠系水利用率可提高10％，实现了水资源量测与管理的数字化、动态化、智能化与一体化。     

不同灌水方式对棉花黄萎病发病的影响

2004年和2005年在石河子大学实验站黄萎病圃进行了滴灌和沟灌两种不同灌水方式对棉花黄萎病发病影响的试验.结果表明,无论从生长期的病情,还是最后剖杆检查的病情来看,滴灌发病均重于沟灌,中后期表现更为明显.     

Progress in study on irrigation practice with saline groundwater on sandlands of Taklimakan Desert Hinterland

The study on the distribution and dynamic changes of soil moistures and salts under different irrigating methods and managements of using saline groundwater on the sand lands of the hinterland of the Taklimakan Desert, started in 1997. The results show that drip irrigation can be applied to seedlings （furrow irrigation can be applied to level lands） using saline groundwater in the process of constructing the biological shifting sand control system along the desert highway in the hinterland of the Taklimakan Desert; an irrigation frequency of 20 clays and an irrigation amount of 30 kg/m^2.time are suitable to the shifting sand control forest belts at the same year as they were afforested. Along with the increase of forest age, the irrigation norm can be properly increased, the irrigation interval can be prolonged.     

棉花膜下滴灌湿润峰的试验研究

以试验为基础,对重壤土、中壤土和沙土的湿润峰与滴头流量间的关系,以及湿润峰的演变规律进行了研究,得出了适用于不同土壤的滴头流量和滴头间距。另外,验证了“一膜一管”布置形式的可行性,提出了该条件下棉花栽培方式的改进要求。试验结论与生产实际吻合很好。     

The Central Guizhou and Yi-chang uplifts, Upper Yangtze region, between Ordovician and Silurian

The Central Guizhou and Yichang Uplifts are present in central Guizhou to western Hubei. Biostratigraphic evidences from more than 20 sections in 14 counties of this region provide the data about the duration of these uplifts. Although this duration differs from locality to locality, it is mainly from Ashgillian to Rhuddanian. The uplifts result from a horizontally driven movement to the South China Paleoplate from an uncertain block in southeast. Global sea-level drop during the end of the Ordovician made the uplifts obvious, particularly the Central Guizhou Uplift. It might have emerged above sea level in the short interval between the Ordovician and Silurian.