Exploring the combination of biochar‐amended soil and automated irrigation technology for water regulation and preservation in green infrastructure

Biochar is a carbon sink material with the potential to improve water retention in various soils.However,for the long‐term maintenance of green infrastructure,there is an additional need to regulate the water contents in the covers to maintain vegetation growth in semiarid conditions.In this study,biochar‐amended soil was combined with subsurface drip irrigation,and the water preservation characteristics of this treatment were investigated through a series of one‐dimensional soil column tests.To ascertain the best treatment method specific to semiarid climatic conditions,the test soil was amended with 0%,1%,3%,and 5%biochar.Automatic irrigation devices equipped with soil moisture sensors were used to control the subsurface water content with the aim of enhancing vegetation growth.Each soil column test lasted 150 h,during which the volumetric water contents and soil suction data were recorded.The experimental results reveal that the soil specimen amended with 3%biochar is the most water‐saving regardless of the time cost.Soil with a higher biochar content(e.g.,5%)consumes a more significant amount of water due to the enhancement of the water‐holding capacity.Based on the experimental results,it can be concluded that the appropriate ratio can be determined within 1%–3%,which can reduce not only the amount of irrigated/used water but also the time cost.Such technology can be explored for water content regulation in green infrastructure and the development of barriers for protecting the environment around deep underground waste containment.

Difficulties and Countermeasures of Developing Irrigation and Water Conservancy in New Era

This paper expounds the great significance of irrigation and water conservancy for the agricultural development. Vigorously developing irrigation and water conservancy can promote high yield and stable yield of grain, effectively increase farmers' income, alleviate the impact of drought on agricultural production, be conducive to the adjustment of agricultural production structure, and promote county economic development. The difficulties of developing irrigation and water conservancy in new era are analyzed as follows: the subject of liabilities defaults seriously; it lacks effective input security system; the quality of project degenerates badly; the agricultural technological development is slow. Corresponding policy suggestions are put forward as follows: make the input subject of irrigation and water conservancy clear; form stable investment channels; strengthen the organizing and guiding functions of grass-roots government; reinforce the coordination and management of capital; strengthen the promotion of agricultural technology; quicken the pace of reform of irrigation and water conservancy.

Design of Farmland Water Conservancy and Irrigation Management System Based on GIS

The farmland irrigation project is an important part of China's water conservancy project. To keep abreast of the farmland water conservancy and various related environmental parameters,we can use the external sensors to acquire real-time data,employ the computer technology,networking and communication technology,database technology,geographic information system( GIS) technology,component technology and other advanced modern information technologies combined with the automated water conservancy technology,in order to build an accurate,efficient,fast,comprehensive,standardized decision support system integrating farmland water conservancy and irrigation information collection,transmission,storage,management and analysis. In this paper,we give details about the overall framework design of farmland water conservancy and irrigation management system based on GIS,information collection and data input,and information processing and data output,to provide a reference for the digital water conservancy construction in China.

Effects of water application intensity of microsprinkler irrigation on water and salt environment and crop growth in coastal saline soils

Laboratory and field experiments were conducted to investigate the effects of water application intensity（WAI） on soil salinity management and the growth of Festuca arundinacea（festuca） under three stages of water and salt management strategies using microsprinkler irrigation in Hebei Province, North China. The soil water content（è） and salinity of homogeneous coastal saline soils were evaluated under different water application intensities in the laboratory experiment. The results indicated that the WAI of microsprinkler irrigation influenced the è, electrical conductivity（ECe） and p H of saline soils. As the WAI increased, the average values of è and ECe in the 0–40 cm profile also increased, while their average values in the 40–60 cm profile decreased. The p H value also slightly decreased as depth increased, but no significant differences were observed between the different treatments. The time periods of the water redistribution treatments had no obvious effects. Based on the results for è, ECe and p H, a smaller WAI was more desirable. The field experiment was conducted after being considered the results of the technical parameter experiment and evaporation, wind and leaching duration. The field experiment included three stages of water and salt regulation, based on three soil matric potentials（SMP）, in which the SMP at a 20-cm depth below the surface was used to trigger irrigation. The results showed that the microsprinkler irrigation created an appropriate environment for festuca growth through the three stages of water and salt regulation. The low-salinity conditions that occurred at 0–10 cm depth during the first stage（-5 k Pa） continued to expand through the next two stages. The average p H value was less than 8.5. The tiller number of festuca increased as SMP decreased from the first stage to the third stage. After the three stages of water and salt regulation, the highly saline soil gradually changed to a low-saline soil. Overall, based on the salt desalinization, the microsprinkler irrigation and three stages of water and salt regulation could be successfully used to cultivate plants for the reclamation of coastal saline land in North China.

River Treatment and Measures in Water Conservancy Projects of Small Farmland

China is country of massive agriculture.Although it has gradually changed from traditionalagriculture to modern agriculture in recent years, thereare still many problems in the transition. Rivers playan important role in water conservancy projects offarmland. Therefore, full attention should be paid toriver management of farmland. This thesis analyzes itand proposes countermeasures for governance.

Effects of Regulated Deficit Irrigation on Twig Water Potential of Korla Fragrant Pear

With 7-year-old Korla fragrant pear trees as the experimental material, different root-zone irrigation patterns were arranged to study the effects of soil moisture on twig water potential of Korla fragrant pear trees at different growth stages. The results showed that under the condition of regulated deficit irrigation, the diurnal dynamics of twig water potential of Korla fragrant pear trees was V shaped at different growth stages, and the twig water potential of Korla fragrant pear trees reached the minimum during 14：00-16：00. At different growth stages, the twig water potential of Korla fragrant pear trees under drought stress was significantly lower than that of pear trees irrigated normally. Under both drought stress and normal irrigation, the diurnal variation of twig water potential of Korla fragrant pear trees during the flowering period was most gentle, that during the fruit-setting and mature periods showed some ups and downs, and that during the fruit enlargement period was greater. Under the experimental conditions, the twig water potential of Korla fragrant pear trees was positively correlated with soil moisture content, and the functional relationships between them at different growth stages were studied by regression analysis. In addition, the limits of twig water potential and soil moisture content for normal growth of Korla fragrant pear trees at different growth stages were determined.

Extending the Economic Life of the Ogallala Aquifer with Water Conservation Policies in the Texas Panhandle

The continued decline in the availability of water from the Ogallala Aquifer in the Texas Panhandle has led to an increased interest in conservation policies designed to extend the life of the aquifer and sustain rural economies. Four counties were chosen for evaluation. This study evaluates the effectiveness of five policies in terms of changes in the saturated thickness, crop mix, water use per acre, and the net present value of farm profits over a 60-year planning horizon. The dynamic optimization models were developed using GAMS for the baseline as well as one for all five of the policy alternatives for each county. Results indicate that the policy scenarios of biotechnology adoption and a water use restriction will conserve the most water among the policies analyzed. In terms of economic returns, the biotechnology adoption policy by far provides the greatest benefit to producers due to yield increases that are estimated with current annual growth rates in new seed varieties. The water use restriction policy, on the other hand, has the lowest net present value of returns, indicating that conservation is accompanied with significant costs to producers. The irrigation adoption technology scenario is the next best policy in terms of net present value of returns (following biotechnology);however, it ranks last in terms of reducing aquifer depletion. It is important to note that while the models do not perfectly predict the factors being evaluated, it is the basis for comparison between the policy scenarios which are important. These comparisons will aid policy makers in determining the most effective strategy to conserve water while simultaneously considering the economic costs to producers. In addition, the results of this study can be applied to other areas facing similar conditions, either currently or in the future, throughout the Texas Panhandle.

Moisture Movement and Transformation Law under Soil Moisture Conserving Irrigation in Winter Wheat Field

[Objective] The aim was to provide theoretical basis for field moisture conserving irrigation.[Method] With Xiaoyan No.6 as tested material,three different kinds of mulching irrigation treatments were carried out （straw mulching;plastic mulching;PAM control adjustment mulching）.With non-mulching treatment as control,moisture conserving effect of different treatments were compared.[Result] The results showed that the water consumption of winter wheat under different soil moisture conservation treatments was low at earlier stage and later stage,but high at mid-stage,which was consistent with the water consumption law of control.There were some differences in terms of consumption intensity because of irrigation schedule and growth condition;soil moisture conservation treatments could restrain ineffective evaporation of soil moisture before anthesis.We also found that the variation of soil moisture at depth of 0-20 cm in PAM and control treatment was dramatic.The soil moisture of the former was lower than the latter at the depth of 0-20 cm,but higher at the depth of 20-50 cm.The difference of soil moisture at the depth of 0-50 cm was significant.[Conclusion] Plastic mulching and straw mulching could restrain evaporation effectively.

Crisis of Water Resources on the Ulan Buh Desert Oases, Inner Mongolia, China-A Case Study of Dengkou County

Hetao Plain, composed of hundreds of oases, is one of the most important grain-producing areas in China. Most crops, especially wheat and corn, depend on irrigation, thus water availability is a key issue for grain productivity on this land. The Yellow River is the main water source for irrigation and a crisis of water resources for agricultural use occurs because of increasingly reduced river flows and water-using competition with industry and human residential use. In order to understand the current situation and distribution of water resources on these oases, we collected 20-yr＇s data of river runoff, irrigation volumes, infiltration and precipitation to examine the relationships between water resources distribution and its agricultural use. We found that the oasis in Dengkou county was short of water resources with a water deficit rate of 5.14% in 2010. Based on the trend of the data, water deficit will continue to increase as the population grows in the future. Water resource is a limiting factor to agricultural development in this region and proper management of water use and strategies for water resource conservation are urgently needed. Especially, based on our results we suggest that current irrigation methods need to be greatly improved to save the water that was lost from evaporation.

Agricultural Water Conservation in the High Plains Aquifer and Arikaree River Basin

Yuma County is the top crop producing County in Colorado that is dependent on groundwater supplies from the High Plains aquifer for irrigation. The Arikaree River, a tributary of the Republican River in eastern Colorado, is supplied with water from the High Plains aquifer. The Arikaree River alluvium is also a habitat for many terrestrial invertebrates and the threatened Hybognathus hankinsoni (Brassy Minnow). The constant demand on the High Plains aquifer has created declining water levels at the linear rate of 0.183 m/year with the deepest pool in the Arikaree River drying up in 8 to 12 years. In addition to the demands for habitats, the surrounding irrigated agricultural lands require water for crop production. These challenges are currently confronting farmers in eastern Colorado and this research presents possible alternatives to meet these demands. This research presents a combination water balance model, water conservation model, and water conservation survey results from farmers in eastern Colorado to identify alternatives to extend the life of the Arikaree River. The first alternative was to examine the reduction in irrigation water from removing the 18 alluvial irrigation wells that could extend the Arikaree River pools from drying up for 30 years. The other scenario found that water conservation practices with participation of 43%, 57%, and 62% of farmers would extend the drying time to 20, 30, and 40 years, respectively. The final alternative studied was the required participation in conservation practices to stop the decline of the High Plains Aquifer. The analysis found that 77% participation of farmers in all conservation alternatives or reducing pumping by 62.9% would be necessary to stabilize the High Plains Aquifer.

智慧水利理论体系与数字孪生流域虚拟模型研究成果述要

智慧水利是水利高质量发展的显著标志之一。围绕智慧水利理论体系不完善、流域映射精准度不高、模型精度不高、决策支撑程度低等问题,建立了由智慧流域基础理论、数字孪生流域基础理论和智能水网理论框架组成的智慧水利理论体系,研究了由数字孪生感知节点模型、数字孪生降水遥感模型、数字孪生蒸散发遥感模型、数字孪生土壤水遥感模型、数字孪生水体遥感模型、数字孪生地下水遥感模型、数字孪生水质遥感模型组成的数字孪生流域感知模型,构建了由数字孪生流域水文模型、数字孪生水动力水质模型、数字孪生动态调控模型、数字孪生虚拟仿真模型、数字孪生协同决策模型、数字孪生并行组合模型等组成的数字孪生流域虚拟模型。研究成果可为我国智慧水利建设提供理论基础和技术支撑。

抓好《节约用水条例》贯彻实施推进水资源节约集约利用

《节约用水条例》颁布实施,为依法依规强化节约用水工作提供了良好的法治保障。《条例》以习近平法治思想为指导,以节水优先方针为主线,聚焦节水工作存在的突出问题和薄弱环节,形成促进全社会节约用水的制度体系。《条例》在规范节水行为、促进全社会节约用水方面具有显著特点,为促进水资源节约集约利用奠定了良好法治基础。要抓好《条例》贯彻实施,确保各项规定落地见效。

调亏灌溉技术对葡萄果实品质的影响

由于全球变暖,水资源短缺的风险越来越大,优化传统栽培模式,实行节水灌溉势在必行。调亏灌溉是提高水分利用效率的关键技术。阐述了调亏灌溉机理,从葡萄树体生长状况、根系发育情况及相关蛋白表达调控等多个角度进行了综合分析;概述了分期调亏灌溉、根系分区灌溉和隔行交替灌溉3种调亏灌溉模式,探讨了不同灌溉时期对葡萄生长发育的影响,以及不同物候期对水分的需求及如何根据葡萄的生长周期合理安排灌溉时间;总结了调亏灌溉对葡萄果实中糖分、酸度、酚类化合物及香气物质等关键品质因素的影响。通过对调亏灌溉机理的深入研究,以及对不同灌溉模式和时期影响的探讨,为科学管理葡萄园,实现节水增效,促进农业可持续发展奠定理论基础。

基于水库旱限水位的大型灌区水资源空间均衡优化调控

由于自然地理特征和经济社会活动的差异,大型灌区水资源分布和利用在时空上是不平衡的,尤其是受水文气象波动影响的农业灌溉供水,需要借助水利工程进行水资源空间均衡调控。目前按典型水平年制订的常规调配水方案无法展现水资源空间均衡状态在年内的变化响应过程,也无法考虑水资源在年际间调配的需求。鉴此,本文基于灌区水资源系统空间均衡评价模型和半分布式水资源系统模拟模型,以干旱年缺水时段平均水资源系统空间均衡度最大为目标,以骨干水库分期分级旱限水位和灌区分单元分用水户限供比例为调控变量,运用遗传算法开展大型灌区水资源系统空间均衡优化调控研究。淠河灌区应用结果显示:骨干水库的分级分期旱限水位能够实现水资源在年内和年际时间上的均衡调节,而分单元分用水户的限制供水措施能够使水资源在空间上得到合理配置。二者共同作用能更好地协调灌区供需水在时程分布和空间均衡间的关系,相较于运行现状能大幅提升水资源系统空间均衡度,增强灌区的可持续发展能力,为基于旱限水位的复杂水资源系统管理和应用提供新的思路。

调亏灌溉和秸秆覆盖对苦荞生物学特性和水分利用效率的影响

为探讨调亏灌溉和秸秆覆盖对苦荞生物学特性和水分调亏利用效率的影响,设置秸秆覆盖(裸地S_(1)、秸秆覆盖S_(2))和灌溉方式(常规灌溉M_(1)、轻度调亏灌溉M_(2)、重度调亏灌溉M3)组合共6个处理,比较各处理的土壤含水量、农艺性状、产量和水分调亏利用效率等差异。结果表明:与裸地处理相比,秸秆覆盖处理的产量和水分调亏利用效率分别提高了13.5%和32.9%。与全灌处理相比,轻度调亏灌溉处理的产量、水分调亏利用效率分别提高了5.3%和52.8%。调亏灌溉和秸秆覆盖互作后,M_(2)S_(2)处理下产量和水分调亏利用效率最高。M_(2)S_(2)的产量、水分调亏利用效率较M_(1)S_(1)分别增加16.1%,95.7%,主要是因为M_(2)S_(2)处理的净光合速率、单株分枝数、生物量及结实率较M_(1)S_(1)分别显著增加13.0%,12.1%,12.5%和8.3%。综上所述,轻度调亏灌溉和秸秆覆盖能显著提高苦荞产量和水分调亏利用效率,可为苦荞的节水高效栽培提供理论依据和技术支撑。

新形势下黄河的治理方略

在阐述近代以来治黄对策和黄河“水少沙多”等问题基础上,提出新形势下黄河下游宽河段治理方略为“三堤共存、槽滩共治”,即以靠溜河道工程为依托,将生产堤改建成坚固的防护堤作为第一道防线,由大堤及其防护工程构成第二道防线,将大堤到控导工程的道路加固成格堤,按“平顺护弯、以弯导流”原则整治河槽,同时在整治工程对岸滩区边沿建护滩工程;对窄河段只需局部扩宽即可大幅提升过洪能力,另需将其中明显碍洪工程进行改造或拆除,解放相关滞洪区并降低宽河段滩区行洪要求。减少入黄沙量的治本之策为采用工程措施与新工艺新材料淤地坝修筑技术,改变水土严重流失区的侵蚀地理环境,结合近自然修复良性生态治理技术,主动拦减流域沟坡产沙并永续发挥生态效益。尽早建成古贤与黑山峡水利枢纽,并激发三门峡这一骨干工程的调控作用,共同构建黄河水沙调控体系的主体构架,建立全河水沙调控及水资源优化配置机制,确保全河水沙关系协调,遏制宁蒙等河段河情恶化势头。为解决黄河下游水少问题,应恢复黄河、汶河洪水进出东平湖条件及南四湖洪水入黄功能,将沿黄已建和拟建平原水库连通,发挥水资源调配作用;若在南水北调中线工程以东修建“河南运河”,黄河下游段即成邻近流域排洪入海通道,将其灾害水变成黄河下游冲沙、灌溉及生态用水;实施“川水济黄、藏水补川”工程,实属关系中华民族永续发展的根本大计。

滴灌节水技术应用机理及热点研究进展

滴灌是一种用水效率高的节水灌溉技术,具有少量多次、节水增产的特点。它能有效减少土壤蒸发和深层渗漏,提高灌溉水利用效率,同时其自动化程度高,可减少劳动力和运行管理成本。滴灌已成为国内外缺水地区的重要灌溉技术之一。目前,我国农业现代化发展过程中广泛使用滴灌技术,但也存在一些问题。从多个层面对滴灌技术的发展现状、适应作物类型、滴灌节水技术应用的研究热点、滴灌节水节肥机理以及存在的问题进行了梳理和分析,并提出了滴灌技术未来发展的建议,旨在为智慧滴灌技术的应用与研究提供借鉴和参考,为有效缓解我国农业用水紧缺,实现农田科学用水,提高作物的水分利用效率和农业生产的可持续性提供理论依据。

农田水利工程确权管理信息系统设计

为解决通过信息化技术手段明晰工程权属,形成可溯源的电子档案,实现工程确权、数据查询等功能,在分析研究功能需求、用户角色需求、数据安全需求以及易用性和可扩展性需求的基础上,提出了包括采集层、数据层、应用支撑层、业务应用层和界面展现层的总体框架,并设计了基于B/S架构的农田水利工程确权管理信息系统。该系统集成了用户管理、农田水利工程管理、工程确权管理等多个业务模块,支持确权申请、审核、公示、证书生成等功能,具有系统可靠和管理一体化的优点,为农田水利工程确权、管理、维护等方面提供全面而高效的支持,为农业可持续发展提供有力支撑。

供水工程影响下中国北方地区耕地后备资源开发潜力

灌溉水源是北方地区耕地后备资源能否有效开发的关键。当前,中国正在推动国家水网工程规划建设,为北方地区耕地后备资源开发提供了新的机遇。在以往研究基础上,该研究考虑北方地区已建、在建及规划的供水工程,基于自然适宜、利用高效、发展稳定三方面评价准则,结合三维魔方空间分类方法,开展了雨养情景和供水灌溉情景下耕地后备资源开发潜力分析。结果表明:雨养农业情景下,北方地区勉强适宜(Ⅱ级)、中度(Ⅲ级)和高度(Ⅳ级)适宜的耕地后备资源面积分别为2.9万、1.0万和0.6万km^(2)。灌溉农业情景下,耕地后备资源面积明显增加,勉强适宜(Ⅱ级)、中度(Ⅲ级)和高度(Ⅳ级)适宜的耕地后备资源面积将分别达到5.4万、7.6万和6.5万km^(2),主要集中于新疆、内蒙古和甘肃3省(自治区)。该研究结果可为中国耕地后备资源开发利用及国家水网工程效益发挥提供参考。

面向绿洲安全和干旱区可持续发展的农业节水潜力研究

为确保用水总量控制下绿洲安全及干旱区可持续发展目标的实现,以新疆开孔河流域为例,提出基于用水总量控制指标、地下水安全等约束条件的干旱区灌溉节水潜力计算新方法。结果表明:1)开孔河流域现状年(2020年)地下水开采量为12.97亿m^(3),灌溉用水总量为34.85亿m^(3);传统节水模式下,流域中期规划年(2030年)节水潜力为0.74亿m^(3),远期规划年(2050年)节水潜力为5.02亿m^(3)。2)在节水潜力新内涵下,开孔河流域中期规划年没有节水潜力,且需要休耕18667 hm^(2),远期规划年节水潜力为1.77亿m^(3)。3)为防止干旱区次生盐渍化,实现水资源短缺的干旱区可持续发展,在节水后应控制绿洲地下水位在3.5~4.0 m之间。对于水土不均衡的干旱区灌区而言,传统节水思路对绿洲安全的重视程度不够,对节水潜力评价过高。