Water Quality Retrievals from High Resolution Ikonos Multispectral Imagery: A Case Study in Istanbul, Turkey

This paper presents an application of high resolution satellite remote sensing data for mapping water quality in the Goldon Horn, Istanbul. It is an applied research emphasizing the present water quality conditions in this region for water quality parameters; secchi disc depth (SDD), chlorophyl-a (chl-a) and total suspended sediment (TSS) concentration. The study also examines the retrievals of these parameters through high resolution IKONOS multispectral data supported by in situ measurements. Image processing procedure involving radiometric correction is carried out for conversion from digital numbers (DNs) to spectral radiance to correlate water quality parameters and satellite data by using multiple regression technique. The retrieved and verified results show that the measured and estimated values of water quality parameters in good agreement (R ²?>?0.97). The spatial distribution maps are developed by using multiple regression algorithm belonging to water quality parameters. These maps present apparent spatial variations of selected parameters and inform the decision makers of water quality variations in a large water region in the Istanbul metropolitan area.     

气象因子对高香气烤烟品种主要香味前体物含量的影响

为研究气象因子对高香气烤烟品种主要香味前体物质含量的影响,以烤烟品种‘云烟87’为对照,对高香气烤烟品种‘豫烟11号’在5个不同地点的主要香味前体物质含量进行了比较,并分别对2个品种的香味前体物质与气象因子进行了关联度分析。研究结果表明:‘豫烟11号’主要香味前体物质含量在每个地点均显著高于‘云烟87’。烟叶类胡萝卜素在低纬度地区的含量显著低于高纬度地区,多酚类物质的含量随着海拔降低、成熟期光照时数增加而逐渐增加,叶片腺毛分泌物整体上高纬度地区的含量显著高于低纬度地区,以河南卢氏的含量最高。2个品种的烟叶类胡萝卜素含量受成熟期日照时数、旺长期平均气温等光温因素影响较大,而烟叶大田生长期间日照时数的长短对多酚类物质含量影响较大。2个品种的烟叶石油醚提取物和腺毛分泌物含量与气候因素的灰色关联度趋势有较大差异,‘豫烟11号’烟叶石油醚提取物含量受烟叶生长期间的日照时数影响较大,‘云烟87’则受平均气温的影响较大。‘豫烟11号’烟叶腺毛分泌物含量受成熟期日照时数和旺长期平均气温等的影响较大,‘云烟87’则受伸根期平均气温、成熟期蒸发量和成熟期平均气温等的影响较大。高香气烤烟品种‘豫烟11号’在选择种植区域时,应充分考虑成熟期日照时数和旺长期平均气温对品质的影响。     

基于病害高发期气象因子的三七病害发生率预测

准确预报病害发生率是提前应对三七病害、提高产量和品质的重要基础。该研究利用2018－2019年云南红河州三七种植基地内田间气象数据和病害发生率资料,采用主效应分析（Principal Components Analysis, PCA）来避免多元共线性的发生。以2018年和2019年的5－9月气象数据集作为训练集与验证集,以随机森林（Random Forest, RF）算法作为基础学习机构建初步预测模型,最后通过梯度下降（Gradient Descent, GD）算法进行优化。结果表明,土壤温度与棚内湿度均与病害发生率呈正相关,其皮尔逊相关系数在0.25～0.75之间,棚内土壤热通量和三七冠层上方土壤热通量均与病害发生率呈负相关,其皮尔逊相关系数在-0.75～-0.25之间;通过随机森林获得的模型的均方根误差为0.23;通过梯度下降优化,代价函数收敛时值为241.003,并获得各个气象因子对三七病害高发期的病害发生率影响的权重,其中土壤温度正相关程度最大,权重为21.686,三七冠层上方的土壤热通量负相关程度最大,权重为-13.834。该研究结果在通过田间气象因子预测三七病害高发期的病害发生率上具备可靠的预测能力,可为降低三七病害的设施环境调控和智能化管理提供理论依据和技术支持。     

Evaluating urbanization,fragmentation and land use/land cover change pattern in Istanbul city,Turkey from 1971 TO 2002

Spatiotemporal analysis of landscape dynamics is crucial in formulating an appropriate set of actions in landscape management. This paper presents a large scale analysis of the spatiotemporal structure of Istanbul, a highly urbanized city in Turkey, from 1971 to 2002 using forest cover type maps analysed with geographical information systems (GIS) and a spatial statistics programme. The quantitative evidence indicated that increasing population and expanding urbanization caused drastic changes to the temporal and spatial dynamics of land use/land cover pattern in Istanbul. There was a net increase of 5387·3 ha in total forested areas (1·0 per cent) due to mainly reforestation activities even though the population increased three times over a 31‐year period. Increase in number of patches and decrease in mean patch size together demonstrated that the landscape developed into a more fragmented structure that would negatively affect biodiversity and the resilience of the ecosystems. In conclusion, plain increase in forest areas may not always be a favourable situation. The quality, composition and the configuration of forest landscape should also be analysed to present the dynamics of ecosystem in terms of ecological and economical sustainability over a longer time and larger area. Copyright © 2008 John Wiley & Sons, Ltd.     

Estimate of health impacts of acidifying air pollutants and tropospheric ozone in Europe

Based on combined information available from air quality monitoring data and long-range transport models, European population exposure to SO₂, NO₂ and O₃ has been estimated. This information has been combined with the results of epidemiological studies assessing strength of association between the exposure and health effects to estimate an impact of the pollution on health in Europe. The analysis indicates that a considerable number of health problems, ranging from mild irritation of the respiratory system to increased mortality, can be attributed to short-term peaks of pollution observed in Europe. Chronic impacts of prolonged elevated SO₂ levels on lung function are estimated to occur in close to10 million people in Europe.     

ATR-FTIR Spectroscopic Study of Functional Groups in Aerosols: The Contribution of a Saharan Dust Transport to Urban Atmosphere in Istanbul,Turkey

This paper reports on the effect of activating agents such as the impregnation ratio of phosphoric acid (1:1–1:5) at constant activation temperature on the performance of porous activated carbon from waste residues (maize tassel). The variation in the impregnation ratio of the produced activated carbon (AC) from 1:1 to 1:5 enabled the preparation of a high surface area (1,263 m²/g) and a large pore volume (1.592 cm³/g) of AC produced from maize tassel (MT) using a convectional chemical activating agent (phosphoric acid). Impregnation ratios (IR) of the precursors were varied between 1:1 and 1:5 in which it was found that the ratio of 1:4 was optimal based on the high surface area, while 1:5 has the optimal pore volume value for the produced activated carbon.     

基于AMSR-2蒙古高原土壤水分反演及 对气象因子响应分析

土壤水分是地表水文过程研究的一个重要参数,是众多环境因子综合作用的结果,科学判定土壤水分对环境因子的响应特性,对在蒙古高原地区开展干旱监测预警,调整农业生产结构,改善区域生态环境具有重要意义。本研究基于AMSR-2观测亮温、SPOT-NDVI数据,利用微波辐射传输模型及粗糙地表发射率Qp模型,构建适合蒙古高原的土壤水分反演方程,同时将模型应用于2013年蒙古高原植被生长期土壤水分反演。在此基础上,结合TRMM 3B43降雨量及气象站点气温数据,探讨了蒙古高原土壤水分对气象因子及植被的响应特性。结果表明:1)构建的蒙古高原表层土壤水分反演模型精度较高,土壤水分反演值与实测值的判定系数为0.680 6,均方根误差(RMSE)达0.031 6 cm3·cm-3,反演结果明显优于JAXA提供的AMSR-2土壤水分产品数据(RMSE=0.044 1 cm3·cm-3)。2)TRMM 3B43降雨数据与实测降雨量线性拟合,其判定系数为0.859 8,直线拟合斜率K=0.941 5,在数值上较站点实测值略微偏低,表明TRMM 3B43数据精度较高,在蒙古高原具有很好的适用性。3)蒙古高原植被生长期土壤水分、植被指数及降水量在空间格局上均表现出由北向南、由东北向西南逐渐减少的趋势。干旱区,土壤水分对气温变化最敏感,二者表现出显著正相关关系,其次为降水和植被;半干旱区,植被是影响土壤水分的关键因子,而气温与降水对土壤水分影响呈现出季节性变化;半湿润区3个因子对土壤水分的影响程度表现为植被降水气温。总之,利用土壤水分对气象因子和植被的响应特性,可以采取适当措施降低蒙古高原灾害发生风险,为区域生态环境建设提供科学依据。     

Modeling of thermoregulation in the skunk cabbage in relation to meteorological factors

A model is proposed to calculate the spadix temperature of the skunk cabbage Symplocarpus foetidus which regulates its internal temperature at around 20 °C during the female stage even when the ambient air temperature drops below freezing. The model is based on energy balance of the spadix under field conditions. The input data are standard meteorological data and spadix parameters. The model output was compared with experimental data collected under different climate conditions. The agreement between observed and calculated spadix temperatures was fairly good.     

稻瘿蚊重发的气象原因分析与防治对策

针对宁都县近年来稻瘿纹常有重度发生的情况，进行气象条件分析。结果表明：冬季气温明显偏高，水稻生长季节雨日、雨量明显偏多，有利于稻纹的重度发生，造成水稻大减产。因此，提出了些有效的防治对策，做到及时预测，及时防治。     

桃树茎直径微变化与土壤水势及气象因子的关系

通过对充分供水和逐步干旱处理的盆栽“仕女红”桃树茎直径微变化动态的观测,分析了茎直径日最大收缩量(MDS)、日增长量(DI)和日最大值恢复时间(RT)对水分状况和气象因子的响应,并对适宜灌溉控制指标进行了探讨.结果表明:随土壤水势降低,桃树茎直径MDS和RT呈增大趋势,DI呈下降趋势并由正值变为负值;气象因子对桃树茎直径变化影响显著,太阳辐射(Rn)和空气相对湿度(RH)对MDS影响最强烈,连续降雨对DI和RT影响显著.DI受土壤水势影响产生变化的趋势明显并受气象因子影响较小,是最理想的灌溉控制指标,可将DI=0作为灌溉控制临界值;MDS受气象因子影响强烈,变异性较大,且需要充分灌溉条件下的MDS作为参考,RT与土壤水势的相关性不高,因此均不适合单独作为灌溉控制指标.     

玉米收获机割台振动特性及其主要影响因素分析

针对收获机械割台振动剧烈、故障率较高等问题,研究了割台动态振动特性及其影响规律。以4YZP-3XH-1型玉米联合收获机割台为研究对象,首先建立了割台机架有限元模型并计算其自由模态,研究了割台模态试验方法,利用特征实现算法识别其模态参数;其次,利用模态试验验证了有限元模型的准确性和可靠性,在此基础上,计算获取割台机架的约束模态;再次,利用时域和频域方法分析振动时域信号,获得怠速、运输和田间收获工况割台的振幅分布特征、主振方向和频率分布规律;最后,研究了割台振动的影响因素及其振动主频与模态参数之间的对应关系,指出了振动频率激起模态振型的规律。研究结果表明,割台机架第1阶试验模态频率为27.260 Hz,第2~10阶模态频率范围为34.311~126.035 Hz,模态振型以弯曲振型和扭转振型为主,割台主轴(28.77 Hz)、切碎刀(29.63 Hz)、还田机(43 Hz)等工作频率均落入其前10阶约束模态频率内;在怠速、运输和田间收获作业工况下,工作部件运行工况相较于仅发动机工作,2种模式下割台振幅相差1个数量级;引起割台振动的主要因素为:发动机的2阶发火频率(76.25 Hz),割台主轴、切碎刀、搅龙、拨禾链、还田机等工作部件的耦合振动,以及道路激励(1.5、2.5 Hz)。对比割台约束模态与振动频率,发动机2阶发火频率引起割台弯扭组合振型,道路激励引起整体振动,割台主轴(28.77 Hz)和切碎刀(29.63 Hz)振动频率激起割台机架的一阶弯曲振型,还田机(43 Hz)振动频率激起割台的扭转振型。研究结果可为收获机械割台模态试验与振动特性分析、对标设计和优化提供参考。     

Redistribution of organic pollutants in river sediments and alluvial soils related to major floods

Background, Aims, and Scope  More frequent occurrence of stronger floods in Europe as well as in other parts of the world in recent years raises major concern about the material damages, but also an important issue of contamination of the affected areas through flooding. The effects of major floods on levels and distribution of contamination with hydrophobic organic pollutants were examined from the continuous set of data for floodplain soils and sediments from a model industrial area in the Czech Republic where a 100-year flood occurred in 1997. The goal of this study was to evaluate the risk related to contamination associated with such extensive natural events and characterize the spatial and temporal distribution and dynamics of pollutants related to a major flooding shortly after the floods and also in the time period several years after floods. Methods  Sediments and alluvial soils from fourteen sites each were repeatedly sampled during the period from 1996 until 2005. The sampling sites represented five regions. Collected top-layer sediment and soil samples were characterized and analyzed for hydrophobic organic pollutants PCBs, OCPs and HCB using GC-ECD and PAHs using a GC-MS instrument. Spatial and temporal differences as well as the relative distribution of the pollutants were examined in detail by statistical analysis including multivariate methods with special emphases placed on the changes related to floods. Results  The organic pollutants levels in both alluvial soils and sediments exceeded the safe environmental limits at numerous sites. Pollutants concentrations and relative distribution as well as organic carbon content in both sediment and floodplain soils were significantly affected by the flooding, which resulted in a decrease of all studied contaminants in sediments and significant rise of the PAH pollution in the flooded soils. There was a unique and highly conserved PAH pattern in soils regardless of the floods and greater changes in PAH pattern in sediments related to floods. The relative distribution of individual PAHs reflected a combustion generated PAH profile. PAH levels in the river sediments rose again at the sites with continuous sources several years after floods. Discussion  The results showed different dynamics of PAHs and PCBs during the floods when PAHs were redistributed from the sediments to alluvial soils while PCBs have been washed out of the study regions. The data reveal longer contamination memory and consistent contamination pattern in soils, whereas sediments showed more dynamic changes responding strongly to the actual situation. The stable PAH pattern within the regions also indicates that a relative amount of all compounds is comparable across the samples and, thus, that the sources at different sites have similar character. Conclusions  Sediments have the potential to function as a secondary source of contamination for the aquatic ecosystem, but also for the floodplain soils and other flooded areas. The floods served as a vector of PAHs contamination from sediments to soils. The reloading of river sediments in time, namely with PAHs, due to present sources increases their risk as a potential source in the next bigger flood event both to the downstream river basin and affected alluvial soils. Recommendations and Perspectives  The results stress the importance of including the floodplain soil contamination in the risk assessment focused on flood effects. Floodplain soils have stable long-term environmental memory related to contamination levels, pattern and distribution, whereby they can provide relevant information on the overall contamination of the area. The sediments will continue to serve as a potential source of contaminants and alluvial soils as the catchment media reflecting the major flood events, especially until effective measures are taken to limit contamination sources. ESS-Submission Editor: Dr. Henner Hollert (Hollert@uni-heidelberg.de) This article is openly accessible!     

日光温室番茄不同空间尺度蒸散量变化及主控因子分析

明确日光温室作物不同空间尺度蒸散量及变化规律是提高水分利用效率、实现农业水资源合理配置的关键。该文针对华北地区典型日光温室,于2015—2016年在中国农业科学院新乡综合试验基地,以滴灌番茄为研究对象,参考20 cm标准蒸发皿的累积蒸发量,设计充分灌溉和亏缺灌溉2种水平,研究不同水平下番茄叶片蒸腾、单株耗水(用茎流速率表征)和群体蒸散量的日变化和生育期变化,并采用通径分析法确定影响不同空间尺度蒸散量的主控因子。结果表明:叶片蒸腾和气孔导度随太阳辐射变化,峰值出现在10:00—14:00之间,移栽54~58 d后充分和亏缺处理的叶片蒸腾和气孔导度开始出现差异;充分和亏缺处理的单株耗水在晴天差异最大,阴雨天最小,且滞后太阳辐射约1 h;全生育期充分和亏缺处理的日群体蒸散量分别在0.32~6.65和0.15~5.91 mm/d之间变化,群体蒸散量在盛果期最大,占总耗水量的31.7%~34.7%。净辐射对叶片、单株和群体尺度的蒸腾量影响均显著,而水汽压差仅对单株和群体尺度蒸散量影响显著,估算日光温室番茄单株耗水和群体蒸散量时需考虑风速影响。水分胁迫条件下,考虑叶温变量可显著提高单株耗水和群体蒸散量的估算精度。研究可为不同空间尺度蒸散量转换方法的选择以及尺度提升理论模型的构建提供借鉴。     

基于气象要素空间分布模拟优化的中国草地综合顺序分类

依据草地综合顺序分类系统(CSCS)原理,利用中国区域1961—2004年的气象信息数据,以及1km分辨率的DEM(高程)数据,借助ArcGIS平台,采用优化的气象要素模拟方法——多元回归+残差分析(AMMRR),以及3种传统插值方法,模拟了中国多年平均的>0℃年积温(Σθ)和年均降水量(r)的空间分布,并利用AMMRR法对中国草地进行分类。研究结果表明:1)AMMRR模拟得到的Σθ和r与实测样本的相关系数分别为0.976和0.974,极显著相关(p<0.01);相对平均误差(RME)、平均绝对误差(MAE)和均方根误差(RMSE)都小于3种传统插值方法。2)AMMRR通过经纬度、海拔高度与气象要素间的多元回归以及残差分析修正,不仅弥补了原始站点不足且分布不均匀的缺点,而且也充分体现了海拔落差较大区域气象要素的垂直变化。气象站点分布密集的区域,4种方法模拟的效果较一致,其空间格局与真实地理环境相似;但站点稀疏而且分布不均匀的区域,只有AMMRR的模拟结果才能反映出小尺度空间分布中地形的空间分异作用,结果比较理想。3)依据CSCS,中国草地包括除炎热极干热带荒漠类(ⅦA7)的其他41个地带性草地类。从南到北,Σθ减小,依次分布着炎热潮湿雨林类(ⅦF42)-亚热潮湿常绿阔叶林类(ⅥF41)-暖热潮湿落叶、常绿阔叶林类(ⅤF40)-暖温潮湿落叶阔叶林类(ⅣF39);从东向西,r降低,依次分布着微温潮湿针叶阔叶混交林类(ⅢF38)-微温湿润森林草原、落叶阔叶林类(ⅢE31)-微温微润草甸草原类(ⅢD24)-微温微干温带典型草原类(ⅢC17),地带性规律明显。     

Effect of ozone and sulphur dioxide pollutants separately and in mixture on chlorophyll and carotenoid pigments ofOryza sativa

Exposure of rice plants to low concentrations of O₃ and SO₂ singly and in combination showed foliar injury of different levels. The maximum leaf injury was noted in case of O₃+SO₂ treated plants and the minimum in O₃ treated ones. Also the reductions in chlorophylla,b and total chlorophyll and carotenoid contents in leaves exposed to O₃+SO₂ mixtures were higher than the reduction noted in case of each individual pollutant. Thus the results suggest a synergism existing between O₃ and SO₂ regarding plant injury, especially with respect to chlorophyll and carotenoid contents of rice (Oryza sativa).     

Identification of risk factors for sub-optimal housing conditions in Australian piggeries: Part 2. Airborne pollutants

The concentrations of total airborne bacteria, respirable endotoxins, ammonia, and respirable and inhalable particles were monitored in 160 piggery buildings in Australia between autumn 1997 and autumn 1999. The overall mean airborne bacteria, respirable endotoxins, ammonia (NH3), and inhalable and respirable particle concentrations measured were 1.17 x 10(5) cfu m(-3), 33.1 EU m(-3), 3.7 ppm, 1.74 mg m(-3), and 0.26 mg m(-3), respectively. The characteristics of the buildings and management systems used were documented at the time of sampling. A multifactorial general linear model (GLM) statistical procedure was used to analyze the effects of housing and management factors on the concentrations of the airborne pollutants. Both airborne bacteria and respirable endotoxin concentrations were affected by building classification (type), and respirable endotoxin concentrations were positively correlated with increasing humidity. The concentrations of airborne bacteria increased as the level of pen hygiene (cleanliness) decreased. The NH3 concentrations were primarily affected by level of pen hygiene, building volume, pig flow management, and season. Building classification, pig flow management, season, building volume, ventilation rates, and temperature affected inhalable particle concentrations. Respirable particle concentrations were primarily affected by building classification, pen hygiene, pig flow management, season, ventilation rates, temperature, and humidity. These findings suggest that environmental improvement strategies (such as improved cleaning, ventilation, and temperature control) are likely to reduce airborne pollutant concentrations in pig buildings and in the environment, thus improving the health and welfare of both pigs and farm staff.     

气象因子对甘蔗不同下种方式出苗状况的影响

本文通过两年的田间试验,分析了气象因子对桂糖１１号和新台糖１６号这两个甘蔗品种的４种不同下种方式,即砍种浸种（Ⅰ）、砍种不侵种（Ⅱ）、不剥叶不砍种（Ⅳ）的出苗状况的影响。结果表明：在土壤干旱条件下,甘蔗的出苗时间大大延迟;处理Ⅱ、Ⅲ、Ⅳ下种方式的出苗时间受土壤水分影响很大。甘蔗旬出苗数与旬降雨量及土壤含水量呈线性正相关关系,尤其是处理Ⅲ相关极显著。在土壤干旱条件下,甘蔗幼苗死苗率与干旱天数呈显著线     

Analysis of morphological,pomological and yield characteristics of some apricot germplasm in Turkey

The purpose of this study was to characterize the Irano-Caucasian apricot germplasm that was collected in Anatolia, Turkey. Fifteen (pomological, phenological, and yield) parameters were studied in this germplasm, consisting of 128 apricot cultivars and types. A wide variation was found in harvest season, fruit yield, total solids soluble (TSS), total acidity, fruit, pit, and kernel mass. Most of the cultivars and types had a relatively small fruit size; only seven had a fruit mass ≥50 g. In general, fruits had yellow skin ground color and flesh color as well as mostly sweet kernels and high TSS. While there was a high correlation between fruit, pit and kernel mass and also between TSS and total acidity, a low or no significant correlation was determined between other pomological or phenological characteristics. The Levent apricot type possessed a substantially late ripening with a total period of 190–200 days for fruit development, a characteristic that makes this apricot type highly suitable for breeding studies.     

Storage and release of major ionic contaminants from the snowpack in the Turkey Lakes Watershed

The chemistry of the snowpack and snowmelt was investigated at the Turkey Lakes Watershed during the spring melt period in 1985. Ions in the snowmelt were 2 to 10 times more concentrated than those in the pre-melt snowpack and approximately 50% of the H⁺, SO₄ and NO₃ were lost from the snowpack with the first 30% of the melt. Rainfall flowed directly through the snow cover even during the early stages of the melt. Four rain events, which accounted for only 18% of the flowthrough collected, were responsible for about 50% of the H⁺ and SO₄ and 37% of the NO₃ ions exported from the snowpack. Sulphate to nitrate equivalent ratios in the pre-melt snowpack were generally about 0.6 but an enrichment of S04 relative to N03 in atmospheric deposition during the spring (SO₄:NO₃ > 1) resulted in snowmelt with an increasing SO₄ content relative to NO₃.     

Modelling diurnal and seasonal patterns of maize pollen emission in relation to meteorological factors

Modelling the risk of cross-pollination between maize crops can help to define efficient isolation methods to reduce the risk of gene flow between these crops. However, the use of such models over the pollen emission season is limited by poor estimations of pollen emission. In this study, we present a model that predicts hourly pollen emission fluxes over the pollen season and that accounts for effects of both meteorological conditions and crop variety. It consists of two sub-models that predict: (i) the seasonal pattern on a daily basis and (ii) the normalized diurnal pattern on an hourly basis.To assess the variability of pollen emission, ten field experiments were carried out in July and August over four years using three crop varieties. The model was built from (i) a parameterisation of the measured diurnal and seasonal patterns of pollen emission followed by (ii) a quantification of the relationships between parameter values and meteorological conditions. Total production of pollen was fairly constant for a given variety over years and sowing dates, while patterns of emission varied with meteorological conditions. The pollen emission season was longer when temperature was low and humidity was high. In most cases, the diurnal pattern was unimodal: the onset and the peak of emission were delayed when relative humidity was high or wind speed was low. In some cases, a second peak of emission occurred during the afternoon. This was observed more frequently when temperatures were high.