双道HG-AFS同时测定鲤鱼肝脏中痕量Hg和As

应用氢化物原子荧光法,测定鲤鱼肝脏中痕量Hg和As,该法具有原子吸收和原子发射光谱两种技术优势,同时它具有分析灵敏度高,干扰少,线性范围宽,可多元素同时测定等优点;在KBH4-酸还原体系中同时测定鱼肝中Hg和As,方法检出限分别为Hg:0.33ng/ml和As0.36ng/ml,线性范围分别为:0.1-2.0ng/ml和1.0-20.0ng/ml。加标回收率分别为Hg:96.0%和As:100.6%。分析结果可靠,方法令人满意,并适合大批量样品的分析。     

Classification of residential areas according to physical vulnerability to natural hazards: a case study of Çanakkale,Turkey

The selection of new settlement areas and the construction of safe buildings, as well as rendering built‐up areas safe, are of great importance in mitigating the damage caused by natural disasters. Most cities in Turkey are unprepared for natural hazards. In this paper, Çanakkale, located in a first‐degree seismic zone and sprawled around the Sartçay Delta, is examined in terms of its physical vulnerability to natural hazards. Residential areas are analysed using GIS (geographic information system) and remote‐sensing technologies in relation to selected indicators. Residential areas of the city are divided into zones according to an evaluation of geological characteristics, the built‐up area's features, and urban infrastructure, and four risk zones are determined. The results of the analysis show that the areas of the city suitable for housing are very limited. In addition, the historical centre and the housing areas near Sartçay stream are shown to be most problematic in terms of natural disasters and sustainability.     

Spatiotemporal changes of landscape pattern in response to deforestation in Northeastern Turkey: a case study in Rize

Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management of forest ecosystems. This study analyzes spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in Rize Forest Enterprise of the Northeastern part of Turkey. The area is investigated by evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of forest cover type maps from 1984 and 2007 using GIS and FRAGSTATS. The quantative evidences presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover. As an overall change between 1984 and 2007, there was a net decrease of 2.30% in total forested areas. On one hand, productive forest areas decreased 12,506 ha, on the other hand, degraded forest areas increased 14,805 ha. In examining the changes of crown closure and development stages of forest ecosystem during the study period, the forest stand area with medium crown closures increased. Regenerated area increased while the other development stages were left to grow to mature development stages in the period. These results regarding to crown closure and development stage showed that forest quality has increased but total forest areas decreased. This is partially due to out-migration of rural population in Rize and Cayeli towns. In terms of spatial configuration, analysis of the metrics revealed that landscape structure in Study area had changed substantially over the 23-year study period, resulting in fragmentation of the landscape as indicated by the large patch numbers and the smaller mean patch sizes due to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments.     

Analysing urban expansion and land use suitability for the city of Kahramanmaraş, Turkey, and its surrounding region

This study aimed at quantifying changes in urban area of the city of Kahramanmara? (K.Mara?) between 1948 and 2006, and analysing suitability of existing land use (LU) to the land potential. Urban change information was derived from two black-white monoscopic aerial photographs, and IKONOS and the QuickBird images acquired in 1948, 1985, 2000 and 2006, respectively. QuickBird image and soil map with 1:25,000 scale were used to analyze suitability of the current LU pattern to the land potential. The findings showed that the urban area of K.Mara? has expanded approximately 13 times during the past six decades. According to current LU and the soil map, productive and moderately productive soils were largely (73.2%) allocated for agricultural activities, which means that there was a strong consistency between the agricultural LU type and the land capability. However, widespread agriculture on the non-productive soils, and urbanization on the fertile agricultural lands were assessed as unsuitable from sustainable LU viewpoint. Considering this phenomenon, it is possible to say that rapid urban expansion has a growing pressure on the fertile agricultural soils. Monitoring LU changes, particularly urbanization, and developing effective LU plans based on the land capability were determined as the most important approaches to encourage sustainable use of land.     

区域灾情评价模型

自然灾害发生的次数和灾害种类与灾情强度密切相关，因此有必要对灾情强度进行合理的评价。首先用灾次指数Di和灾种指数Di′来量化单灾种的多发性和多灾种的群发性，提出了计算Di和Di′的方法，然后在此基础上建立了量化灾情强度指数Q的模型，该模型适用于单区域和多区域中多种灾害发生的情况。对北京市怀柔、平谷和海淀3个区进行了模型的实例应用，考虑洪灾、冰雹灾和旱灾3种灾害情况，结果表明，怀柔区的灾情强度指数高于平谷和海淀区，3种灾种中冰雹灾的灾情强度指数高达42．76％。     

Improving Operational Planning and Management of National Parks in Turkey: A Case Study

The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment.     

Determining the impact of urban components on land surface temperature of Istanbul by using remote sensing indices

For the past 60 years, Istanbul has been experiencing an accelerated urban expansion. This urban expansion is leading to the replacement of natural surfaces by various artificial materials. This situation has a critical impact on the environment due to the alteration of heat energy balance. In this study, the effect upon the urban heat island (UHI) of Istanbul was analyzed using 2009 dated Landsat 5 Thematic Mapper (TM) data. An Index Based Built-up Index (IBI) was used to derive artificial surfaces in the study area. To produce the IBI index, Soil-Adjusted Vegetation Index, Normalized Difference Built-up Index, and Modified Normalized Difference Water Index were calculated. Land surface temperature (LST) distribution was derived from Landsat 5 TM images using a mono-window algorithm. In addition, 24 transects were selected, and different regression models were applied to explore the correlation between LST and IBI index. The results show that artificial surfaces have a positive exponential relationship with LST rather than a simple linear one. An ecological evaluation index of the region was calculated to explore the impact of both the vegetated land and the artificial surfaces on the UHI. Therefore, the quantitative relationship of urban components (artificial surfaces, vegetation, and water) and LST was examined using multivariate statistical analysis, and the correlation coefficient was obtained as 0.829. This suggested that the areas with a high rate of urbanization will accelerate the rise of LST and UHI in Istanbul.     

Groundwater quality assessment in semi-arid regions using integrated approaches: the case of Grombalia aquifer (NE Tunisia)

As many arid and semi-arid regions in the Mediterranean Basin, the Grombalia coastal aquifer (NE Tunisia) is affected by severe groundwater exploitation and contamination. Therefore, quality assessments are becoming increasingly important as the long-term protection of water resources is at stake. Multidisciplinary investigations, like the one presented in this paper, are particularly effective in identifying the different origins of mineralization within an aquifer and investigating the impact of anthropogenic activities on groundwater quality. An integrated assessment, focused on the combined use of geostatistical, geochemical and isotopic (δ¹⁸O, δ²H and ³H) tools, was performed in the Grombalia aquifer between February and March 2014. The overall goal was to study the main processes controlling aquifer salinization, with special focus to nitrate contamination. Results indicate a persisting deterioration of water quality over the whole basin except the south-eastern zone juxtaposing the recharge area of the aquifer. Nitrate contents exceed the drinking water standard (50 mg/l) in 70% of groundwater samples, mainly due to the excessive use of fertilizers and urban activities. Stable isotope measurements showed the contribution of modern rainwater to aquifer recharge and proved the presence of evaporation contributing to the salinity increase. Tritium values of groundwater samples suggested two hypotheses: the existence of mixture between old and recent water or/and the existence of two recharge periods of the aquifer, pre- and post-nuclear weapons test. Principal component analysis confirmed the geochemical interpretation, highlighting that water-rock interaction evaporation effect and intensive anthropogenic activities constitute the main processes controlling the regional groundwater mineralization.