水肥一体化技术在生姜生产中的应用

为了解决生姜生产中存在的费水、过度施肥、营养失衡、人工投入大、生姜产量低和品质不高的突出问题,本研究把水肥一体化技术和生姜生产实践结合起来,从生姜地块的土壤理化性状检测、设备选择与设计、水源选择、肥料选择以及生姜各生育期的水肥投入方案等方面,阐述了水肥一体化技术在生姜生产中的应用技术要点,形成了具有普遍指导性的水肥一体化技术规范。该技术要点体现了水肥一体化的技术优势,可为各生姜产区的生姜生产、广大农技推广人员农技推广服务和农业领域科研工作者提供技术指导和参考。     

滇中冷凉山区不同播期反季花椰菜产量效益分析

为摸索滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期以集成高效栽培技术推广应用,于2017—2018年选择海拔2250 m的云南省峨山县塔甸镇大西村地块进行9个播期的2年随机区组试验。结果表明,花椰菜生育期随播期推迟而延长,而花球采收期除播期7月10日外随播期推迟而逐渐增长;花椰菜株高、外叶数、开展度、球高、球径和单球重等农艺性状有随播期延迟呈现先逐渐减小而后又逐渐增大的趋势;莲座期黑腐病和霜霉病的病情指数随着播期的延迟呈现先逐渐升高而后又逐渐下降的趋势;花椰菜小区产量随着播期的延迟呈现先逐渐下降而后又逐渐提高的趋势,播期4月20日和4月30日与其余7个播期产量之间的差异达极显著水平。综合花椰菜在冷凉山区反季节栽培的生产实际和各播期产量产值及商品性表现,推荐滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期为4月20—30日。     

芜湖市5所公园地被植物应用状况分析

为进一步明确地被植物在城市公园中的景观应用,采用实地调研的方法,记录并分析安徽省芜湖市内的赭山公园、镜湖公园、九莲塘公园、滨江公园（一期）和雕塑公园的地被植物应用状况。结果显示,5所公园常用地被植物共有94种,其中草本41种、木本53种,麦冬等7种草本及洒金桃叶珊瑚等32种木本地被植物应用最多;各公园的滨水区域地被植物应用各具特色,常应用迎春花、火棘等地被植物作为衔接。笔者就芜湖市公园地被植物应用方面提出了思考与建议,为城市公园地被植物应用提供参考。     

Assessing the utility of topographic variables in predicting structural complexity of tree stands in a reforested urban landscape

The transformation of natural landscapes into impervious built-up surfaces through urbanization is known to significantly interfere with the ecological integrity of urban landscapes and accelerate climate change and associated impacts. Although urban reforestation is widely recognised as an ideal mitigation practice against these impacts, it often has to compete with other lucrative land uses within an urban area. The often limited urban space provided for reforestation therefore necessitates the optimization of the ecological benefits, which demands spatially explicit information. The recent proliferation of tree stands structural complexity (SSC) and topographic data offer great potential for determining the ecological performance of reforested areas across an urban landscape. This study explores the potential of using topographic datasets to predict SSC in a reforested urban landscape and ranks the value of these topographic variables in determining SSC. Tree structural data from a reforested urban area was collected and fed into a tree stand structural complexity index, which was used to indicate ecological performance. Topographic variables (Topographic Wetness Index, slope, Area Solar Radiation and elevation)- were derived from a Digital Elevation Model (DEM) and used to predict SSC using the Partial Least Squares (PLS) regression technique. Results show that SSC varied significantly between the topographic variables. Results also show that the topographic variables could be used to reliably predict SSC. As expected, the Topographic Wetness Index and slope were the most important topographic determinants of SSC while elevation was the least valuable. These results provide valuable spatially explicit information about the ecological performance of the reforested areas within an urban landscape. Specifically, the study demonstrates the value of topographic data as aids to urban reforestation planning.     

Harbour seal (Phoca vitulina) abundance within the Firth of Tay and Eden Estuary,Scotland: recent trends and extrapolation to extinction

1. Aerial surveys have detected alarming declines in counts of harbour seals in several regions across Scotland.
2. Demographic data and simple models were used to examine the recent decline in the numbers of harbour seals counted in one population within a Special Area of Conservation (SAC) on the east coast of Scotland. The models suggest that the continuation of current trends would result in the species effectively disappearing from this area within the next 20 years.
3. While the cause of the decline is unknown, it must be reducing adult survival because the high rate of decline cannot be wholly accounted for by changes in other demographic parameters.
4. Recovery of the population to the abundance recorded at the time the SAC was designated (2005) is likely to take at least 40 years, even if the cause of the decline is immediately identified and removed.
5. The models suggest that partial removal of the cause can have only limited benefits to population recovery, and there are unlikely to be any long‐term benefits from introducing or reintroducing additional individuals while the underlying problem persists. Therefore, if the population of harbour seals in this area is to recover it is essential that the sources of the increased mortality are identified and measures are put in place to manage these.

Copyright © 2015 John Wiley & Sons, Ltd.     

南繁区稻瘟病菌遗传多样性和群体遗传结构的AFLP分析

【目的】为了明确南繁区稻瘟病菌(Magnaporthe oryzae)的遗传分化情况,【方法】采用AFLP分子标记技术对南繁核心区(三亚、乐东和保亭)和非核心区(琼中、屯昌和定安)共60个稻瘟病菌菌株的遗传多样性和群体遗传结构进行了比较分析。【结果】聚类分析表明,几乎所有菌株都聚在同一个谱系里,并且该谱系没有明显的亚群;群体遗传结构分析表明,核心区群体的多态性位点百分率、Shannon信息指数和基因流分别为87.89%、0.2738和4.2897,高于非核心区群体的81.37%、0.2703和3.5892;然而,核心区群体的Nei基因多样性指数和基因分化系数分别为0.1657和0.1044,低于非核心区群体的0.1662和0.1223。【结论】这些结果表明核心区和非核心区菌株都存在丰富的遗传多样性,不同群体间均存在较多的基因交流,但遗传变异均主要来自群体内;相比之下,核心区菌株的遗传多样性和遗传分化程度较高。     

Soil water response to precipitation in different microtopographies on the semi-arid Loess Plateau,China

Soil water is an important factor restricting afforestation on the semi-arid Loess Plateau.The microtopography of the loess slope has changed the distribution pattern of soil water on the slope.To improve water utilization efficiency and optimize afforestation configuration patterns,the relationship between soil water and precipitation at micro-topographic scale must be studied.We used time series analysis to study the temporal variation of soil water and its response to precipitation in four kinds of micro-topographies and undisturbed slope on loess slopes.Micro-topographies significantly influenced soil water distribution and dynamics on the slopes.Soil water stored in the platform,sinkhole,and ephemeral gully influenced subsequent soil water for 4 weeks,whereas soil water stored in the scarp and undisturbed slope could influence soil water for 2 weeks.It took 12 weeks,10 weeks,18 weeks,6 weeks,and 12 weeks for precipitation to reach the deeper soil layer in the platform,sinkhole,scarp,ephemeral gully,and undisturbed slope,respectively.These soil water characteristics in different micro-topographies are vital factors that should be taken into consideration when undertaking afforestation on the Loess Plateau.     

Recreational fisheries in Portofino Marine Protected Area,Italy: Some implications for the management

Since the 1970s, recreational fishing has become a mass hobby in Italy, reaching a large number of people, who, using modern equipment, increased their harvesting capacity, provoking serious conflicts with the professional fisheries. Recreational fishing is strictly regulated inside Italian Marine Protected Areas (MPAs) and is generally allocated to local residents, mainly to reduce the tensions caused by limitations of access to the resources. The aim of this study was to provide an analysis of recreational fishing activities within the Portofino MPA (Mediterranean Sea), to assess the possible impact on the local fish stocks and to plan potential management actions. Furthermore, some serious inconsistencies on the minimum lengths of fish caught as defined by law relative to the minimum size of first reproduction are discussed. Since 2014, all anglers exploiting the Portofino MPA have been obliged to fill out a logbook. The compilation of these was not completely satisfactory, when compared with a group of reliable anglers whose catches were accurately monitored, but allowed for estimated yields of about 24 kg/angler/yr. After 15 years of protection, the fish biomass has increased within the Portofino MPA, generating a positive spillover effect. At the same time, it has attracted many anglers whose gross harvesting was estimated at about 8 t/year, representing about the 8% of the total yield of the local small‐scale fishery.     

重庆地区玉米黏虫僵虫体内虫生真菌的分离鉴定

玉米黏虫(Mythimna separata)是一种常见的鳞翅目害虫,具有暴发性和迁飞性,对农作物危害严重.虫生真菌是昆虫病原微生物中的最大类群,可以有效地控制自然界中害虫的种群数量.为了防治玉米黏虫和与玉米黏虫相近的草地贪夜蛾,丰富虫生真菌菌种资源,以采自重庆江津高粱地中的玉米黏虫僵虫为实验材料,运用传统培养方法分离鉴定了6株真菌.经过形态学观察和分子生物学鉴定将这6株真菌归类于3个属,分别为镰刀菌属(Fusarium)、青霉属(Penicillium)以及鬼伞属(Coprinellus).虫生真菌能够引发昆虫感染发病,将害虫的种群数量长期控制在较低水平以下,在生物防治方面很有意义.此次分离纯化得到镰刀菌属(Fusarium)和青霉属(Penicillium)的真菌均有潜在的杀虫能力,鬼伞属(Coprinellus)真菌具有防治线虫的潜力,这些真菌对玉米黏虫和草地贪夜蛾的杀虫效果还有待于进一步的实验研究.     

用遥感影像提取大别山区水稻种植面积——以Landsat 8为例

本研究选取安徽省安庆市大别山为研究区,包括太湖县、岳西县、宿松县和潜山县,选取2016年和2017年的6景Landsat 8卫星遥感影像,通过遥感影像提取水稻种植面积,分析大别山区的水稻种植面积分布,并对研究区域的水稻种植面积进行动态实时监测。用遥感解译方法分别提取了研究区内的晚稻种植面积,并利用随机点验证和Kappa系数验证结果精度。结果表明:2017年和2016年水稻种植面积的提取精度分别为93.44%、93.78%,Kappa系数分别为0.86、0.83,证明水稻提取效果精确;对比研究区域各个县内的2017年和2016年晚稻种植面积,发现安庆市大别山区太湖县、潜山县、岳西县的水稻种植面积变化率均在5%以内,属于正常变化,由于2016年宿松县遭遇了水灾,部分农田被淹没,故宿松县2017年水稻种植面积相比2016年增加了13.01%;对比传统的农作物种植面积统计方法,利用遥感的方法更省人力、物力、财力,并且能精确、快速地实现对农作物的实时动态监测。