共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
选择3种不同的退耕地,即前茬为水稻地、黄豆地和草皮地,进行混播人工草地建设。分析测定了6个组合、2个混播比例(3:7和5:5)在不同退耕地中的生长速度、总产量、组分产量及各组分比例。结果发现不同退耕地显著影响人工草地产量及组分变化。黄豆地产量显著高于水稻地和草皮地(p<0.01)。而草皮地豆科牧草产量又显著高于黄豆地和水稻地(p<0.01)。同时,不同组合的产草量及组分比例随着刈割时间的不同而不同。草皮地中各牧草第2次刈割产量平均较第1次提高430%。3种土壤中,除F组合3:7混播比例外,2个组合不同混播比例苇状羊茅与鸭茅的比值都是第2次小于第1次。 相似文献
3.
高羊茅草坪草生长发育与抗逆效应研究进展 总被引:1,自引:1,他引:0
摘 要:高羊茅属于多年生冷季型草坪草,具有较强抗性和适应性,在我国广泛栽培应用。本研究综述了高羊茅国内外研究进展,主要从高羊茅生长发育、栽培技术、抗性效应等方面阐述,并对其发展趋势进行展望,旨在为高羊茅的深化研究与合理利用提供参考。 相似文献
4.
Design of GIS-based monitoring and maintenance decision support system for urban sewage pipe network
Monitoring and maintenance of sewer system is important to city water environmental management. A method for pipeline monitoring and maintenance decision support system (PMMDSS) based on geologic information system (GIS) and decision making system (DSS) is developed for upgrading sewer system maintaining efficiency. Visual basic (VB) and standardized Active X components are employed in PMMDSS, which selected SuperMap Objects as the development platform. PMMDSS integrates the spatial and model system to achieve the decision analysis for the sewer system monitoring and maintenance. An application Software is developed based on a case study in Yuechi Country of Sichuan Province. The software can be used to dynamically monitor the heath condition and provide an optimum visual decision making platform for the city sewer system. 相似文献
5.
基于价值当量因子分析的四川省农业生态系统服务价值评价研究 总被引:1,自引:0,他引:1
农业生态系统服务价值不仅关乎民众福祉,也为实现乡村生态振兴奠定坚实基础.开展农业生态系统服务价值评价,旨在为加强农业生态环境保护提供科学依据.以四川省农业生态系统为研究对象,基于单位面积价值当量因子法,结合皮尔生长曲线模型和恩格尔系数计算社会发展阶段系数,测得2000-2017年四川省农业生态系统服务价值的实际值.结果... 相似文献
6.
China Ministry of Construction started a Netherlands Government's grant project named with 'Development and Demonstration of Feasible Technologies for Environmental Infrastructure in China's Western Small Cities' in 2003.And establishing a technical guide for domestic refuse disposal is one of the project components.In order to perform the project well,investigations were made into the current situation of domestic refuse disposal over selected representative small towns in Sichuan,Yunnan and Shanxi provinces which are located in western areas of China,and existing problems in design and construction,management,environmental monitoring,staff training and investment are analyzed.Some suggestions,mainly including setting up a national special fund for western domestic refuse disposal,moving toward integrated domestic refuse management system,establishing a particular technical guide of domestic refuse disposal suitable for western small cities and implementing charge system,are proposed in the end. 相似文献
7.
截留是植被对降水的第1次再分配,是重要的水文要素之一。目前,大多数植被截留的研究都是以乔木和灌木为主,关于草冠截留的研究还是相对欠缺。笔者针对目前草坪草冠层截留研究的现状和所存在的问题,从草冠截留的主要影响因素(降雨量、降雨强度、叶面积或叶面积指数等)以及现有草冠截留量测定方法和装置2个方面论述了草冠截留的研究进展。分析表明:草被植物的截留影响因素研究主要是以降雨条件、叶面积指数和草被盖度,以及草被植物本身特征为重点,各因素的综合交互作用影响研究非常缺乏;测定方法在精确度和适用范围上也有待提高。 相似文献
8.
为研究大宗淡水鱼养殖和产业空间优化问题,基于标准椭圆模型,以大宗淡水鱼产量最多的草鱼为研究对象,2006—2016年国内31个省级行政区草鱼产业养殖规模为基准,分析草鱼产业发展的空间分布格局(集聚度、重心、范围、方向)、演变特征及影响因素。研究表明,国内草鱼产业空间演变呈离散化集聚发展态势。长江流域中上游地区产量的稳步增加,西北干旱、半干旱地区的草鱼养殖扩大,推动了草鱼产业标准椭圆向西、向北偏移。草鱼产业发展的空间布局呈现分散化集聚,草鱼养殖逐渐由粗放型养殖向精细化养殖方式转变,产业发展在空间上存在由中东部向西、向北传递机制。这主要是草鱼具有良好的环境适应性、中西部成本较为低廉和市场扩大效应导致的。 相似文献
9.
10.
不同尿素施肥水平对北方混播草坪中土壤各形态氮的影响 总被引:2,自引:0,他引:2
本文的目的是为了研究北京地区冷季型草坪合理的施肥制度,了解尿素施用对混播草坪土壤中各形态氮的影响。通过土壤渗滤水采集装置试验,研究尿素施用对草地早熟禾和高羊茅的混播草坪的生长情况和对土壤当中各形态氮素含量的影响。尿素施用共分为,低氮(年施氮量为10g m-2,相当于尿素 25g m-2)、中氮(年施氮量为25g m-2,相当于尿素62.5g m-2)、高氮(年施氮量为40g m-2,相当于尿素100g m-2)三个施肥水平。各处理中的尿素分别在春季和秋季平均施用。结果表明: 本试验中最佳施肥量是:年施尿素62.5g m-2(相当于氮量为25g m-2),在该水平下,草坪草能迅速吸收氮素,促进草坪植物生长; 试验还得出,施用尿素的水平与实验后土壤中全氮、铵态氮、硝态氮和碱解氮含量并不呈正相关。 相似文献
11.
Esteban Rios Kevin Kenworthy Ann Blount Kenneth Quesenberry Bryan Unruh John Erickson Fredy Altpeter Patricio Munoz 《Plant Breeding》2017,136(2):253-260
The development of a turf‐type bahiagrass could have a remarkable impact on the billion‐dollar turf industry in the south‐eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H2) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H2 indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation. 相似文献
12.
为蒙东地区荫蔽环境合理选用不同类型的草坪草种植提供借鉴。以冷季型草坪草草地早熟禾的优异(Merit)、新哥来德(Nu Glade)和肯塔基(K.B.G)3个品种和紫羊茅的2个品种宝瑞(Boreal)和梦神(Rubra),共5个品种草坪草为研究对象,在人工遮荫控制下,对其幼苗耐荫性进行了比较研究。试验设置的遮荫处理分别是:遮荫度22%,45%,66%,83%,以不遮荫的全光照为对照(CK)。结果表明:苗期遮荫显著提高了草坪草(肯塔基)的株高(P0.05),株高先增加后降低,幼苗生长细弱,高遮荫度对株高生长也产生抑制,幼苗株高以全光照的最低,45%或66%遮荫下株高达到最高,83%遮荫时株高显著(新哥来德除外)降低(P0.05);遮荫对幼苗根系生长有抑制作用,根系长度随遮荫度增加而降低;随着遮荫度提高,各品种的叶片含水量和茎含水量逐渐增加,叶绿素含量先增后减,叶绿素a/b值先降低后增加,可溶性糖含量逐渐降低。 相似文献
13.
利用1981—2010年重庆市34个气象观测站的日(20时—20时)降水量资料及空间间隔为2.5°×2.5°的NECP/NCAR逐6小时再分析资料,对重庆西部区域性阻塞型暴雨天气过程进行统计合成分析,结果表明:(1)导致渝西阻塞型暴雨的大尺度环流背景场为稳定的“两槽一脊”型环流,贝加尔湖低槽与东移的四川盆地低槽同位相叠加,副高西伸并稳定维持,位势场呈现“西低东高”的特点;(2)来自于南海地区的水汽持续输送至重庆西部地区为暴雨过程的产生和维持提供了有利的水汽条件;(3)暴雨发生前后温湿场发生了明显变化,温度场上暴雨发生前和发生时暴雨区附近有着较强的暖平流,而暴雨发生后为明显冷平流,湿度场上700hPa上10g/kg等比湿线及850hPa上15g/kg等比湿线可作为渝西阻塞型暴雨的一个预报参考指标。 相似文献
14.
呼伦贝尔市旅游气候适宜度分析 总被引:1,自引:1,他引:0
为了能够对呼伦贝尔市旅游气候资源价值做出评价,帮助旅游产业健康科学发展,通过人居舒适度等级、体感温度、着衣指数等几个方面对呼伦贝尔市旅游气候适宜度进行分析,并提出游览时间、目的地及穿衣建议。结果表明,对于休闲避暑为目的的游客最好选择6、7、8月,若有参观岭西北部林区的游客选择7月为最佳,6、8月需携带外套,而冬季游览、滑雪的游客可选择1、2、3、11、12月,其中1、2、12月冻伤危险较大,需做好防寒措施,春秋季节温度变化大,根据目的地着衣指数选择装备,旅游管理部门应结合各季节和景区所在地的气候适宜度情况妥善管理旅游资源、开发旅游项目。游客可根据自身旅游目的及情况科学选择合适时间、景区进行游览。 相似文献
15.
《Journal of Landscape Research》2017,(6)
At present, suburban leisure tourism in China is in full swing, but the phenomenon of homogenization is widespread. This paper took suburban leisure tourism of Huayuan Town in Xinjin County, Chengdu, Sichuan for example and summarized the characteristics of Linpan in western Sichuan and market conditions to explore programs for suburban leisure tourism development in line with conditions of Linpan in western Sichuan, with a view to providing a reference for suburban leisure tourism development of Linpan in western Sichuan and suburban leisure tourism development in China. 相似文献
16.
This paper introduces an exam management system, which is applied to the Computer Operating Exam System of Sichuan Computer Graded Examination, aims at the shortage of existing exam ways and exam manager systems. The system bases C/S mode, use SQL Server as background database engine, use Delphi as foreground Development tool, includind data and exam management. It is an independent and comprehensive system, and also can band of existing exam manager system of Sichuan Computer Graded Examination. The system is proposed with emphasis on working-flow, frame, main functions and the solution ways of the key problems. 相似文献
17.
Caitlin Harris Madison Hall Ruby Arrowfield Rowan Herridge Colin Eady Richard Macknight Lynette Brownfield 《Plant Breeding》2023,142(4):518-526
Perennial ryegrass is an important turf and forage grass in temperate regions worldwide. Limited genetic gains have been made with current breeding strategies compared with other grass crops, such as rice and maize, which benefit from Filial 1 (F1) hybrid breeding. One of the largest constraints on hybrid breeding in ryegrass is self-incompatibility preventing inbreeding, as homozygous parental lines are required to develop hybrids with maximal hybrid vigour. Obligate outcrossing in ryegrass has resulted in cultivars with high levels of heterozygosity, lacking trait uniformity across the population. A naturally occurring self-fertile (SF) locus that overcomes the self-incompatibility system has been identified in a European perennial ryegrass population. This study crossed the SF locus into an elite cultivar, producing a self-compatible population that was inbred for several generations. Genotyping-by-sequencing (GBS) was used to assess the population structure and degree of inbreeding in the self-compatible population. Phenotypic analysis indicated that increased homozygosity did not necessarily affect growth and performance. This study concludes that self-compatible ryegrass is a promising tool for hybrid breeding and agronomic improvement of perennial ryegrass. 相似文献
18.
为了解酸雨污染对草坪草生长的影响,以高羊茅和多年生黑麦草为材料,通过盆栽试验,研究不同pH酸雨条件下对草坪草生长和代谢的影响。分别测定生物量、叶绿素含量、超氧化物歧化酶、过氧化物酶、丙二醛和电导率等指标。结果表明,高羊茅和多年生黑麦草鲜重、叶绿素含量等在高酸度、长时间胁迫下整体呈降低趋势,氧化物歧化酶、过氧化物酶则先高后低,丙二醛和电导率则随酸雨pH值减小而有增加趋势。 相似文献
19.
耗散结构视角下的海岛型旅游地系统演化机制研究————以妈祖圣地湄洲岛为例 总被引:1,自引:1,他引:0
摘要:海岛旅游作为海洋旅游的重要组成部分,已成为我国的一个旅游热点。笔者选取福建湄洲岛作为研究区域,采用耗散结构理论的研究方法,对湄洲岛旅游地系统演化机制进行研究,以期对海岛型旅游地发展提供借鉴。研究结论认为:湄洲岛旅游地系统主要负熵来源有自然过程、社会过程、旅游开发过程以及旅游运营过程的负熵输入,海岛旅游地演化实质是基于耗散结构负熵不断输入的结果;湄洲岛旅游地系统演化的动力主体呈多元化格局,由于海岛用地的多功能性,更应注重演化动力主体的协调作用;作为海岛型旅游地更多的是受到旅游需求、海岛发展的政策引导和外部交通网络改善等背景动力的影响,通过动力主体的协调作用,进而促使系统内部有序性增加;湄洲岛当前处于系统优化阶段,应适时调整旅游产品结构,促进旅游产品多样化,协调好发展旅游与传承妈祖文化之间的冲突,实现旅游者与海岛居民共享设施,做到宜居、宜行、宜游,从而提高游客的体验度,是湄洲岛旅游地系统优化的关键所在。 相似文献
20.
Tall fescue is an important outcrossing forage and turf grass species that requires vernalization to flower. A reproducible protocol was developed for vernalization of regenerated, transgenic and seed‐derived tall fescue plants. Following the vernalization scheme that involved gradual changes of temperature and daylength, seeds were routinely produced from vernalized plants under greenhouse conditions. Molecular analyses of progenies obtained from crosses between transgenic and seed‐derived plants revealed stable meiotic transmission of transgenes following Mendelian inheritance in transgenic tall fescue. 相似文献