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601.
初论新疆环境域类型特征及对策 总被引:1,自引:0,他引:1
在进行环境保护时,首先必须对环境进行域类型划分,然后对划分的环境域特征以及它们之间的相互制约、影响的关系进行研究,并确定对不同的环境域采用不同的措施和对策,以达到环境保护的目的。本文初次对新疆的环境域进行了划分,在此基础上,对其特征及其相互关系进行了初步研究,最后提出了防治和保护不同环境域的措施及对策。 相似文献
602.
603.
三峡库区消落带土壤剖面中重金属分布特征 总被引:11,自引:3,他引:8
通过对三峡库区消落带土壤的研究,探讨了土壤剖面中重金属的分布特征.结果表明:紫色土淋溶层(A层)w(Cd)和w(Hg)平均值,母质层(C层)w(Cd),w(Zn)和w(Hg)平均值均高于全国同类、同层次土壤的平均水平;石灰岩土A层及C层的重金属质量分数平均值均低于全国同类、同层次土壤的平均水平.从上游至下游,w(Cu)和w(Zn)平均值呈降低趋势,其他重金属质量分数的变化不明显.城区附近土壤重金属质量分数明显高于其他地区.土壤中w(Cd),w(Cr),w(As),w(Hg)和w(Ni)服从正态分布(Sig.>0.05),土壤pH与w(Cd)和w(Cu)之间具有正相关关系(显著性水平为0.01).土壤中w(Cd)与w(Cu),w(Cd)与w(Ni),w(Cu)与w(Zn),w(Cu)与w(Cr),w(Pb)与w(Zn),w(Pb)与w(As),w(Pb)与w(Hg),w(Pb)与w(Ni),w(Zn)与w(Ni)和w(Hg)与w(Ni)之间具有一定的正相关关系;w(Cd)与w(Pb),w(Cd)与w(Zn),w(Cd)与w(As),w(Cu)与w(Ni)和w(Hg)与w(Cr)之间具有一定的负相关关系. 相似文献
604.
Su Yean Teh Donald L. DeAngelis Leonel da Silveira Lobo Sternberg Fernando R. Miralles-Wilhelm Thomas J. Smith Hock-Lye Koh 《Ecological modelling》2008
Sharp boundaries typically separate the salinity tolerant mangroves from the salinity intolerant hardwood hammock species, which occupy the similar geographical areas of southern Florida. Evidence of strong feedback between tree community-type and the salinity of the unsaturated (vadose) zone of the soil suggests that a severe disturbance that significantly tilts the salinity in the vadose zone might cause a shift from one vegetation type to the other. In this study, a model based upon the feedback dynamics between vegetation and salinity of the vadose zone of the soil was used to take account of storm surge events to investigate the mechanisms that by which this large-scale disturbance could affect the spatial pattern of hardwood hammocks and mangroves. Model simulation results indicated that a heavy storm surge that completely saturated the vadose zone at 30 ppt for 1 day could lead to a regime shift in which there is domination by mangroves of areas previously dominated by hardwood hammocks. Lighter storm surges that saturated the vadose zone at less than 7 ppt did not cause vegetation shifts. Investigations of model sensitivity analysis indicated that the thickness of the vadose zone, coupled with precipitation, influenced the residence time of high salinity in the vadose zone and therefore determined the rate of mangrove domination. The model was developed for a southern Florida coastal ecosystem, but its applicability may be much broader. 相似文献
605.
广州帽峰山林区空气负离子动态及与环境因子的关系 总被引:3,自引:0,他引:3
采用定位连续观测方法,研究了广州帽峰山森林公园负离子含量近5年的年、季、月变化及不同天气的变化规律,并以此对帽峰山森林公园的空气质量进行了计量评价.分析了空气负离子含量与环境因子的相关关系.结果表明:林区不同观测区的负离子含量差异较大,山下瀑布空间负离子含量最高.平均水平达达2l 729 ions.cm-3;林内负离子含量年间及月间变化不大,沟谷小溪和山中部瀑布空间由于人为干扰,负离子含量年动态呈现降低趋势,山下瀑布空间年负离子含量维持在20000 iotis·cm-3左右;负离子含量的季节差异显著,春夏季大于冬秋季,夏季最高、冬季最低.空气质量评价系数CI的最低在2月份、最高在8月份.不同天气条件下负离子含量大小顺序为下雨>晴天>阴天.负离子含量与空气温度呈正相关,与空气湿度呈正相关.与空气气压呈负相关. 相似文献
606.
V. M. Shestopalov V. A. Ivanov A. S. Bohuslavsky S. I. Kazakov 《Journal of Coastal Conservation》2008,12(4):169-179
The main engineering-geological hazards and their factors of the Mountain Crimea coastal region are considered. A characteristic
shore line site of Cape Kikineiz and its neighboring coastal area near the Katsiveli settlement has been studied in more detail.
The important characteristic of the site is a high diversity of geological conditions with numerous manifestations of dangerous
engineering-geological processes: shore and hydrological network abrasion, loss of slopes and rocks stability, etc. These
processes have intensified during the last decades under the influence of natural and man-induced factors. The results of
preliminary study of geo-environmental situation of the area are presented. The program for further research and possible
recommendations for rational coastal hazard management and area ecological state improvement are outlined. 相似文献
607.
John Kiousopoulos 《Journal of Coastal Conservation》2008,12(1):19-25
The general objective of this paper is to trigger off the development of a more comprehensive approach to Hellenic coastal
areas (in the perspective of territorial cohesion), at local level and especially along the non-urban areas close to the sea.
Methodological issues linked to the building of an appropriate coastal database constitute the key goal of this paper (the
space and time scale, the relationship to the already proposed set of indicators, the impact of driving forces and policies,
the possible sources of data and their feasibility etc.). Furthermore, specific emphasis should be given to the choice of
new indicators, particularly for the coastal abiotic environment and the land cover/uses along coastal areas, especially near
the seafront. Those indicators should be able to aid the formation (in the near future) of an algorithm linked to the total
man-made activities in coastal areas. In conclusion, this paper will be considered successful if the just above illustrated
objectives could enrich the argument about the typology of coastal areas and the development of a spatial (coastal) observatory.
Actually, this paper is part of a broader research of the author regarding the monitoring of coastal spatial changes in different
scales (AMICA, “Appraisal of man-made interventions along the Hellenic coastal areas”). This research aims to broaden the
coastal knowledge (not only by means of coastal data) on behalf of all stakeholders been implicated into sustainable spatial
planning, integrated coastal management and the strategic environmental assessment along coastal areas.
相似文献
John KiousopoulosEmail: |
608.
Christine Schleupner 《Journal of Coastal Conservation》2007,11(2):91-103
Accelerated sea level rise and hurricanes are increasingly influencing human coastal activities. With respect to the projected
continuation of accelerated sea level rise and global warming one must count with additional expenses for adaptation strategies
along the coasts. On the mountainous island Martinique the majority of settlements are situated along the coast almost at
sea level. But potential rises in sea level and its impacts are not addressed in coastal management, even though saltwater
intrusion and coastal erosion with increasing offshore loss of sediment are locally already a severe problem. At a sea level
rise of 50 cm, one fourth of Martinique’s coastline will be affected by erosion and one fifth of the islands surface will
have high probability to get flooded during coastal hazards. This is a growth of 5% of the impact area in comparison to present
conditions. This article analyses potential adaptation strategies and argues that the development of a coastal zone management
plan considering sea level rise and its impact area is of utmost importance. Empirical assessment models in combination with
spatial analysis are useful in obtaining statements about coastal impacts concerning sea level rise. This paper sees itself
as recommendation of action not only for Martinique.
相似文献
Christine SchleupnerEmail: |
609.
本文运用符号数学MATLAB及MAPLEV计算双层区域模型ASET的方程式,考虑两条基本方程,报告由六所面积10至100平方米的房间,在2个设计火灾下共十二个模式例题的环境及结果也和ASET及FIREWIND程序比较。 相似文献
610.