西藏燕麦主要种植区灌溉定额空间分布及影响因素

燕麦为西藏自治区典型牧草之一,由于种植区地域辽阔,灌溉试验结果受限,西藏燕麦主要种植区的灌溉定额尚不明确。本文在西藏燕麦主要种植区内选取28个典型站点进行资料收集,遵循农业气候相似原则进行区域划分,基于水量平衡法揭示了西藏燕麦主要种植区灌溉定额的空间分布特征,并根据统计学原理分析了其影响因素。研究表明:燕麦主要种植区的灌溉定额呈由西藏中部至东部呈现先递增后递减的趋势,50%水文年下的燕麦灌溉定额在56~265 mm之间变化。降雨量是影响研究区内燕麦灌溉定额的主要因素(R²为0.515),ET₀次之(R²为0.152);其它气象因素中,日照时数对研究区燕麦灌溉定额影响较大(R²为0.462),且呈正相关关系;相对湿度对燕麦灌溉定额影响较小。西藏燕麦主要种植区的灌溉定额及其空间分布可为西藏自治区灌溉用水管理提供支撑。     

Operational scheduling of responsive prosumer farms for day‐ahead peak shaving by agricultural demand response aggregators

This paper proposes a novel structure to optimize the operational strategies of responsive farms for day‐ahead peak shaving. To achieve the aim, the modern irrigation system of farms, including groundwater, surface water, and booster water pumps, are modeled mathematically. To develop the demand response (DR) potentials of the farms, electrical storage systems, and self‐generation facilities, including thermal distributed generations and on‐farm solar sites, are addressed. In order to facilitate the integration of the agricultural DR programs into the electricity market, a mathematical formulation for agricultural demand response aggregator (ADRA) is suggested. The ADRA participates in the day‐ahead electricity market on behalf of the responsive farms. To overcome the price uncertainty of the electricity market, a robust optimization approach is addressed. This approach determines the robust decisions of farms in the worst‐case realizations of the uncertain electricity price. Regarding on‐farm solar sites located in rural areas, a data‐driven approach is used to estimate the solar power generation of a significant number of sites without needing to install costly communication and measurement infrastructures. Finally, the proposed approach is implemented on agricultural lands in the northeast of Iran. The numerical results show that the suggested approach provides day‐ahead peak shaving for the power systems meeting the crop's water requirements.     

Commercial farmers’ strategies to control water resources in South Africa: an empirical view of reform

This article shows how large-scale commercial farmers, individually and collectively, are responding to land and water reform processes in the Thukela River basin, KwaZulu-Natal, South Africa. With a high degree of innovative agency, commercial farmers have effectively executed four strategies, enabling them to adapt and use their access to resources to neutralize multiple water reform efforts that once promised to be catalysts for inclusive change in the post-apartheid era. It is likely that policy alone will not facilitate the envisioned transformation, if local practices are not sufficiently understood and anticipated by the governmental officials charged with the implementation of water reform processes.     

Moving beyond ‘more crop per drop’: insights from two decades of research on agricultural water productivity

ABSTRACT

Concern over increasing water scarcity has led to the introduction of the concept of agricultural water productivity and an emphasis on interventions to achieve ‘more crop per drop’. Yet, a strong debate continues on how the concept is to be defined and used. Drawing largely from the irrigation literature, the origins of the concept and its methodological developments are reviewed, and its use in applied work over two decades is discussed. Based on this analysis of conceptual and applied research, key insights into the concept’s contributions and limitations are presented, as well as opportunities for further refinements.     

农民用水协会考核与评价体系的构建

农民用水协会是农村实施土地承包经营责任制后产生一种新型灌溉管理模式,笔者根据协会的工作性质和内容,从规范运行管理的角度出发,由管理机构、管理人员、管理制度、工程管理、用水管理、财务管理、档案管理和参与管理八个方面介绍了评价指标体系的构建。     

氧化诱导期法探讨滴灌带的热氧稳定性

通过氧化诱导期方法研究了内镶贴片式滴灌带的热氧稳定性,探讨了滴灌带在加工过程中的降解反应及其影响因素,考察了温度、氧气流量对滴灌带氧化诱导期的影响,结果表明,随温度及氧气流量的增加,滴灌带的氧化诱导期呈现下降的趋势。     

海上固定生产平台消防泵数量配置探讨

消防泵设计是海上固定平台设计的重要组成部分。结合规范标准的要求,对海上固定生产平台不同数量的消防泵设计方案进行探讨,分析其优缺点以及适合使用的情况,给出了各种不同设计方案应该考虑的因素。并结合南海海域某固定生产平台的设计实例,对不同数量的消防泵配置进行了分析。     

小议基于单体建筑的现行消防给水系统的弊端

通过分析现代消防给水系统中存在的问题及原因,指出我国目前民用建筑的消防体系是基于单体建筑的防灾系统,是局部的,不完整的。火灾对建筑是偶然事件,对城市则是必然事件。建筑灭火是建筑单体的责任,更是城市防灾体系的一部分,建议加强城市专业化消防管理、灭火、救助力量。建筑的消防职责在于扑灭初起火灾和在最佳控火时间内控制火灾,并及时启动城市相应的消防措施和应急机制。     

论汾河灌区的引洪灌溉

对汾河灌区至汾河水库间的洪水资源、工程现有的引水防沙设施、水沙特性等作了分析 ,并估算了渠道挟沙能力和灌区三个坝的引水量与引沙量 ,总结了引洪灌溉的必要条件