长白山森林景观边界动态变化研究

通过野外调查、遥感和地理信息系统相结合的方法来研究长白山森林景观边界的动态变化规律,并通过相关性分析,探讨了长白山森林景观破碎化过程和景观边界指数变化的关系。首先对遥感影像进行计算机分类,其次,构建了描述景观边界的指标体系,再次,从景观边界的长度、密度、对比度、形状和多样性5个方面,对长白山森林景观边界的动态在景观类型尺度和景观尺度上进行分析。结果表明,在20多年的时问内,苔原面积减少了3694．8hm^2,云冷杉林的面积减少了130482．03hm^2,阔叶红松林面积增加了41610．4hm^2,岳桦林面积增加了66978hm^2．由于森林砍伐和毁林造田以及其它人类活动(如旅游)的影响,长白山森林景观的破碎化程度趋于增加,景观边界形状趋于复杂景观破碎化过程和景观边界指数变化的相关性分析证实了可以用景观形状指数(LSI)、对比度加权边界密度(CWEI))、边界加权总长度(TEGT)、加权景观形状指数(LSI-WGT)的变化来指示森林景观的破碎化程度。景观边界形状指数的大小还可以用来反映人类活动对景观的影响程度。最后,针对目前长白山森林景观破碎化程度趋于增大的情况,建议采取积极措施,防止长白山森林景观的进一步破碎化,以便更好地保护天然林。     

黑土侵蚀区生态重建的景观结构与功能分析

以黑龙江省拜泉县为案例,研究了区域生态恢复与生态重建对景观结构及其水土保持功能的调控.在GIS支持下,结合野外调查数据,对县域水平的生态建设成果进行了空间表达和定量辨识.对比分析1989年和2002年类型水平景观指数及13年来景观类型的转移面积和转移方向、林网宏观结构变化、水库塘坝空间分布与数量变化;土地利用和景观结构调整对水蚀、风蚀的控制以及水库塘坝的蓄水功能变化.结果表明,大规模生态建设下,区域景观类型数量和空间配置的变化对发挥其水土保持功能起到很好的调控作用.1989～2002年,耕地面积减少24731.01hm²,林草地和水体面积增加了13 567.53 hm²和1 190.9 hm².全县55%的水土流失面积得到治理,82.2%的农田得到林网防护,43.7%的景观地表超渗径流得到集蓄.景观结构调整应注意增加林草地等类型斑块的聚集度;调节林网连接度、环度及网眼大小;增加水库塘坝的泄洪与灌溉配套设施等.     

大尺度景观监测信息系统的研究与建立

本文讨论景观监测信息系统(LMIS)的结构框架,并在AST/386和遥感图像处理机上建立了该系统。LMIS系统软件的工作方式采用汇编语言、多种高级语言和数据库语言混合编程的方式,并通过多级功能菜单完成全部功能。LMIS不同于微机GIS,除了GIS的一般功能外,还可对遥感信息进行处理,从而对有关专题数据加以更新,并进行大范围的景观监测。     

长白山森林景观边界动态与气候变化的关系

气候变化对森林景观产生深远的影响,景观边界对气候变化反应尤其敏感。论文采用多元统计分析、遥感和地理信息系统相结合的方法,来定量分析长白山景观边界的变化与气候变化的关系。结果表明:可以利用长白山自然保护区经度、纬度和海拔高度对现存11个气象因子进行空间差值。1975-1997期间,苔原分布的海拔上、下限经历了一个先上升后下降的过程;岳桦(Betula ermanii)分布的海拔上限也有一个先上升后下降的过程,岳桦分布的海拔下限在降低;云杉(Picea koraiensis)冷林(Abies squamata)分布的海拔上限在上升,但其分布的海拔下限的变化没有明显的规律,苔原边界和岳桦分布的海拔上限的变化可能与1月均温和年降水量的变化有关;岳桦分布的海拔下限和云冷杉林分布的海拔上限可能与7月均温有关。     

基于遥感数据的晋陕蒙交汇区景观格局定量分析--以东胜幅1/25万TM影像分析为例

以1996年8月份东胜幅1/25万TM影像数据为例,借助Arc/Info和Arc/view软件,对其景观进行了分类,并形成景观分类图,共分为9类景观类型.用景观格局分析软件FRAGSTATS计算了各类景观参数,并从斑块、类型和景观3个水平上计算了相应的参数和景观指数,定量地揭示了整个景观格局与类型特征.并构建了反映景观破碎化程度的一个指数--斑块密度指数(PD2).     

基于马尔柯夫模型的怒江流域中段植被动态变化预测

运用GIS、RS和GPS技术,采用1994和2004年2个时期的TM影像建立了植被分类系统,分析了2个时期的植被景观格局特征及其变化,并利用马尔柯夫模型,对未来该区域植被景观的动态变化进行了预测。结果表明,怒江流域中段植被景观以灌草丛为基质,其他景观类型镶嵌于其中。1994—2004年,各种植被景观类型之间发生转移最多的是在灌草丛、半湿润常绿阔叶林和针阔混交林之间。变化最大的是海拔较低的灌草丛和半湿润常绿阔叶林等;海拔较高的针阔混交林、寒温性针叶林等的变化均不明显。结果预示,未来10年,人为干扰对整个流域植被演替的影响将进一步加强,灌草丛、寒温性针叶林等面积不断增加,半湿润常绿阔叶林和中山湿性常绿阔叶林面积不断减少,景观整体趋于破碎化,研究区的生态环境受到人类活动严重影响。     

应用地理信息系统模拟森林景观动态的研究

根据地理信息系统的结构,通过数据文件的转换,把它与森林动态模型有机地结合起来,可实现对森林景观动态的模拟和预测。这种模拟方法的数据输入灵活,运行速度快,尤其是它可以获得一些以各种图表的形式输出的模拟结果。本文用文字和框图详细描述了地理信息系统的组成与结构,及森林动态模型的选择与运行方式,并以长白山森林景观为例,叙述了这种模拟方法的整个过程。     

太行古关——晋庙铺的植被景观

晋庙铺镇地处山西省晋东山地的晋城市南部的太行山区,太行山脉耸峙山西高原与华北平原之间,山间天井关是山西高原通向华北平原的天然孔道,是古代的交通要道,为著名的太行八陉之一。全区地形基本上为黄土高原,地势比较平缓,有盆地及平地。高原顶部地势缓而下部则侵蚀沟密集,坡度很大,很多地方超过35度角,平均海拔800米左右。     

北京地区植被景观中斑块大小的分布特征

利用GIS软件ARC/INFO将北京地区的1∶20万植被图数字化，并提取各斑块的面积信息。该图包含72个基本的斑块类型，它们又分属于森林、灌丛、草地、果园、农田和水体6大类型。这些大类又分别包含20、28、4、7、11和2个基本类型。选用斑块个数、总面积、平均斑块面积、标准差、变异系数、中值、最大斑块面积、最小斑块面积、极差和偏态系数等几个描述统计量，以及Γ-分布、对数正态分布、Weibull分布、指数分布和正态分布等5个概率分布来刻画斑块大小的分布特征。结果表明除具有很少斑块的少数基本类型以外，其它基本类型以及所有6个大类的斑块大小的分布都不是对称的，而是右偏的。因此，普通的正态分布不能对它们加以刻画；其他4种概率分布也只能刻画部分类型，并且服从对数正态分布的类型最多，服从负指数分布的斑块类型最少。     

海南岛霸王岭垂直带热带植被物种多样性的空间分析

以常用的Shannon-Wiener指数,Simpson指数以及新近提出的两个非参数指数(Chao多样性指数和二阶刀切法多样性指数),计测了海南岛霸王岭垂直带上不同植被类型(包括热带低山雨林、热带山地雨林、热带云雾林、热带山地矮林)的物种多样性.在此基础上,借助地理信息系统的空间分析技术,模拟绘制了整个梯度的多样性变化谱.总体而言,样带下部的物种多样性高于上部,或者说热带低山雨林与热带山地雨林的物种多样性高于热带云雾林与热带山地矮林,而南部稍高于北部.这种基于插值方法的空间分析技术为探索植被结构分析提供了一条新的途径.     

Biodegradation of phenanthrene by the indigenous microbial biomass in a zinc amended soil

AIMS: To study the effect of zinc on the biodegradation of phenanthrene by the microbial biomass in soil. METHODS AND RESULTS: Uncontaminated soil was amended with zinc and phenanthrene as single or co-contaminants, and microbial metabolic activity was measured using an intracellular dehydrogenase enzyme bioassay over 37 days. Contaminants were amended at optimum, action and double the action level specified in 'The New Dutch List' (Ministry of Housing, Spatial Planning and Environment, the Netherlands, 2000). Microbial activity in soils with zinc or phenanthrene alone indicated the presence of tolerant, albeit inhibited soil micro-organisms. A zinc concentration at the optimum level of 140 mg kg(-1) in the co-contaminated soil (phenanthrene at 40 mg kg(-1)) resulted in marginal stimulation of the rate of phenanthrene biodegradation. However, Zn2+ concentrations at the action and double the action level of zinc (720 and 1440 mg kg(-1)) inhibited phenanthrene degradation. CONCLUSIONS: Biodegradation of phenanthrene in soils co-contaminated with zinc at concentrations above the action value is impeded. SIGNIFICANCE AND IMPACT OF THE STUDY: Bioremediation efforts to remove polycyclic aromatic hydrocarbon in zinc co-contaminated soils are likely to be constrained.     

Soil Contamination at Dumpsites: Implication of Soil Heavy Metals Distribution in Municipal Solid Waste Disposal System: A Case Study of Abeokuta,Southwestern Nigeria

Soil distribution of heavy metals caused by municipal solid waste (MSW) deposition and its implications for MSW management system in emerging cities was investigated in Abeokuta, Nigeria. Results indicated that the highest concentrations of Cu, Cr, Mn, and Zn were observed at 0-40 cm while Pb, Fe, and Ni accumulated at depths below 40 cm. Soils affected by waste deposits from market and auto-mechanic sites showed high levels of Fe, Cr, Pb, Cu, Mn, and Zn. The accumulation of heavy metals in the soils was probably due to the formation of metal-organo-complexes. Therefore, source separation of MSW with proper management systems is proposed to improve the indiscriminate surface dumping practiced at present, while the use of wastes affected sites for cultivation should be discouraged.     

Distribution and health risk assessment of heavy metals in soil surrounding a lead and zinc smelting plant in Zanjan,Iran

One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10^?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.     

Spatial heterogeneity of DTPA-extractable zinc in cultivated soils induced by city pollution and land use

The spatial heterogeneity of DTPA-extractable zinc in the cultivated soils of Shenyang suburbs in Liaoning Province of China was investigated, and its map was drawn by the methods of geostatistics combined with geographic information system. The data of soil DTPA-extractable zinc fitted normal distribution after logarithm transformation, and its semivariogram fitted a spherical model. The semivariogram indicated that the spatial dependence of soil DTPA-extractable zinc content was moderate, with the spatial dependence range of 1.69 km and the fractal dimension of 1.96. Stochastic factors contributed to 49.9% of the spatial variability, while structural factors contributed to 50.1% of it. The spatial heterogeneity of soil DTPA-extractable zinc shown by a kriged interpolation map was deeply influenced by stochastic factors such as city pollution, land use pattern and crop distributions. For example, the average content of Zn in vegetable garden soils was 2.5-4 times as much as in their originated soils, and was lower in paddy soils than in their originated soils. The areas with a higher content of soil DTPA-extractable zinc appeared in the near suburbs and the riverside along Hunhe River and the wastewater drainage of Xihe River, and the extremely high values in the near suburb of the city's residential area were a striking feature, indicating the key role of city pollution in the spatial heterogeneity of soil DTPA-extractable zinc. When recorded in the form of a soil pollution map,the results of such a survey make it possible to identify the unusually polluted areas, and to provide more information for precise agriculture and environmental control.     

Blood screening for heavy metals and organic pollutants in cancer patients exposed to toxic waste in southern Italy: A pilot study

In Italy, in the eastern area of the Campania region, the illegal dumping and burning of waste have been documented, which could potentially affect the local population's health. In particular, toxic waste exposure has been suggested to associate with increased cancer development/mortality in these areas, although a causal link has not yet been established. In this pilot study, we evaluated blood levels of toxic heavy metals and persistent organic pollutants (POPs) in 95 patients with different cancer types residing in this area and in 27 healthy individuals. While we did not find any significant correlation between the blood levels of POPs and the provenance of the patients, we did observe high blood concentrations of heavy metals in some municipalities, including Giugliano, where many illegal waste disposal sites have previously been documented. Our results showed that patients with different cancer types from Giugliano had higher blood levels of heavy metals than healthy controls. Despite the obvious limitations of this exploratory study, our preliminary observations encourage further research assessing the possible association between exposure to hazardous waste, increased blood metals, and increased risk of cancer.     

Spatial heterogeneity of DTPA-extractable zinc in cultivated soils induced by city pollution and land use

The spatial heterogeneity of DTPA-extractable zinc in the cultivated soils of Shenyang suburbs in Liaoning Province of China was investigated, and its map was drawn by the methods of geostatistics combined with geographic information system. The data of soil DTPA-extractable zinc fitted normal distribution after logarithm transformation, and its semivariogram fitted a spherical model. The semivariogram indicated that the spatial dependence of soil DTPA-extractable zinc content was moderate, with the spatial dependence range of 1.69 km and the fractal dimension of 1.96. Stochastic factors contributed to 49.9% of the spatial variability, while structural factors contributed to 50.1% of it. The spatial heterogeneity of soil DTPA-extractable zinc shown by a kriged interpolation map was deeply influenced by stochastic factors such as city pollution, land use pattern and crop distributions. For example, the average content of Zn in vegetable garden soils was 2.5-4 times as much as in their originated soils, an     

重金属污染区土壤酶活性变化

从福建龙岩新罗区特钢厂污灌区农田采集土壤,测定土壤基本理化性质及脲酶、纤维素酶、碱性磷酸酶、多酚氧化酶、过氧化氢酶活性和Cu、Cd、Pb、Zn含量,探讨重金属污染和土壤性质对土壤酶活性的影响.结果表明： 4种全量或有效态重金属与土壤脲酶、纤维素酶、碱性磷酸酶和多酚氧化酶活性呈显著正相关,与过氧化氢酶活性呈显著或极显著负相关;土壤pH与碱性磷酸酶活性呈极显著正相关,粉粒含量与过氧化氢酶活性呈显著负相关.经通径分析,重金属污染刺激了脲酶、多酚氧化酶和纤维素酶活性,但对碱性磷酸酶活性的影响较小.有效态Cu、Cd、Pb、Zn对过氧化氢酶活性的直接影响并不大,但通过间接途径抑制了过氧化氢酶活性.土壤理化性质对5种土壤酶活性的影响较大,碱解氮直接抑制了脲酶活性;全磷直接刺激了碱性磷酸酶和过氧化氢酶活性,并通过有效磷刺激了纤维素酶活性;有效磷直接刺激了纤维素酶活性,直接抑制了碱性磷酸酶和过氧化氢酶活性;全钾直接抑制了碱性磷酸酶和多酚氧化酶活性;速效钾通过有效磷刺激了纤维素酶活性;土壤颗粒组成明显影响多酚氧化酶和过氧化氢酶活性.5种酶活性与土壤Cu、Cd、Pb、Zn含量之间的关系不明确,因此其活性不是指示土壤Cu、Cd、Pb、Zn污染的良好指标.     

黔西北铅锌矿区植物群落分布及其对重金属的迁移特征

重金属耐性植物和超富集植物的筛选、鉴定和驯化是植物修复技术研究与发展的关键。以黔西北4个不同恢复年限的铅锌矿为研究对象,通过群落生态调查利用聚类分析方法筛选出研究区域中重金属耐性植物优势种,并分析其对重金属Pb、Zn、Cu、Cd的迁移富集能力。结果表明:4个矿区共发现高等植物22种,分属13科21属,筛选出9种重金属耐性植物优势种,其中转运系数大于1的植物有:黄花蒿(Cu)、珠光香青(Zn)、大叶醉鱼草(Zn/Pb/Cd)、野艾蒿(Cu/Zn/Pb/Cd);没有富集系数大于1的植物。其中大叶醉鱼草具有耐贫瘠、耐旱、生物量大等优势,可将其作为典型的重金属耐性先锋植物,用于矿区废弃地的植物修复。     

Assessment of metals in agricultural soil of surrounding areas of Urmia Lake,northwest Iran: A preliminary ecological risk assessment and source identification

The aim of this study was to quantify the levels of toxic heavy metals and sodium in topsoil of farmlands around the Urmia Lake. A total of 96 topsoil samples were collected, pre-treated, and analyzed for metals using ICP-AES.

Median concentrations of As, Cd, Cu, Ni, Pb, Zn, and Na in sampling sites were 5, 0.26, 30, 40, 13, 84, and 251 mg/kg, respectively. The enrichment factor, geoaccumulation index, and contamination factor of the metals ranked them in the order of: Na > Pb > Cu > As > Cd > Zn > Ni, indicating minor contamination for them except Na and Pb with moderate contamination. Furthermore, the spatial analysis indicated that Cd, Cu, Pb, Ni, and Zn had similar distribution patterns in the north and northwest lands of the lake. Principal component analysis revealed anthropogenic sources for Cd, Cu, Ni, Pb, and Zn in the soil, whereas, sources of As and Na were most likely related to the dust emitting from the dried bed of Urmia Lake and from a cement industry. Potential ecological risk index in 7% of the sampling sites was at serious or considerable pollution level, and Cd and Pb were identified as the main pollutants.     

重金属污染区土壤酶活性变化——以福建龙岩新罗区特钢厂污水灌溉区为例

从福建龙岩新罗区特钢厂污灌区农田采集土壤,测定土壤基本理化性质及脲酶、纤维素酶、碱性磷酸酶、多酚氧化酶、过氧化氢酶活性和Cu、Cd、Pb、Zn含量,探讨重金属污染和土壤性质对土壤酶活性的影响.结果表明:4种全量或有效态重金属与土壤脲酶、纤维素酶、碱性磷酸酶和多酚氧化酶活性呈显著正相关,与过氧化氢酶活性呈显著或极显著负相关;土壤pH与碱性磷酸酶活性呈极显著正相关,粉粒含量与过氧化氢酶活性呈显著负相关.经通径分析,重金属污染刺激了脲酶、多酚氧化酶和纤维素酶活性,但对碱性磷酸酶活性的影响较小.有效态Cu、Cd、Pb、zn对过氧化氢酶活性的直接影响并不大,但通过间接途径抑制了过氧化氢酶活性.土壤理化性质对5种土壤酶活性的影响较大,碱解氮直接抑制了脲酶活性;全磷直接刺激了碱性磷酸酶和过氧化氢酶活性,并通过有效磷刺激了纤维素酶活性;有效磷直接刺激了纤维素酶活性,直接抑制了碱性磷酸酶和过氧化氢酶活性;全钾直接抑制了碱性磷酸酶和多酚氧化酶活性;速效钾通过有效磷刺激了纤维素酶活性;土壤颗粒组成明显影响多酚氧化酶和过氧化氢酶活性.5种酶活性与土壤Cu、Cd、Pb、Zn含量之间的关系不明确,因此其活性不是指示土壤Cu、Cd、Pb、Zn污染的良好指标.