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151.
Investigation of Pine (Pinus sylvestris L.)annual radial increment (width of annual tree rings) was carriedout in the surroundings of one of the largest pollution sources inLithuania – Jonava Nitrogen Fertilizers Plant. The main objectiveof investigation was to analyse different sides of anthropogenictransformations of tree-ring series in the polluted environment:changes in tree growth intensity; variance changes in tree-ringseries; changes in the relations with natural external factors.Three different periods of tree reaction to the environmentalpollution were singled out – fertilization period, depressionperiod and recovery period since annual emissions were essentiallyreduced. The variance of tree-ring series has increased severaltimes in the polluted environment. Reaction of trees to the impactof climatic factors (temperature, precipitation) has changedsignificantly in the polluted environment and their sensitivity hasalso increased. 相似文献
152.
基于中国统计年鉴中1985~2018年全国能源消耗和人口数据,估计中国城市人为热排放通量及其时间变化趋势.利用人口空间分布和污染物排放清单数据,探讨人为热排放的空间分布特征.依据能源类型,人为热分为工业、交通运输、建筑和新陈代谢4类排放.结果表明,我国人为热排放多年来持续增长,2000年增长加速,2012~2016年增速有所放缓.2016年我国平均人为热排放通量达到0.442W/m2,工业、建筑、交通、新陈代谢排放的全国平均人为热排放通量分别为0.311,0.072,0.038和0.020W/m2.人为热排放的高值主要分布在京津冀、长江三角洲、珠江三角洲重点城市群区域以及其他一些规模较大的区域重点城市.4类人为热排放均呈现东部多、西部少的特点.工业排放人为热分布与区域经济发展水平和城市化程度有关.交通运输排放的人为热主要集中在交通枢纽城市.与已有的人为热排放清单相比,本研究估计的人为热排放通量在规模较大的城市具有更大的数值,更能体现人类活动对人为热排放的贡献. 相似文献
153.
浙江省人为源氨排放清单建立及分布特征 总被引:7,自引:6,他引:1
通过收集各类氨排放源的活动水平数据,选取合适的排放因子以及估算方法,建立了2017年浙江省人为源氨排放清单,分析各排放源的排放分摊率以及浙江省各市的排放情况,并利用ArcGIS对浙江省氨排放量和排放强度的空间分布进行分析.结果表明, 2017年浙江省人为源氨排放量为122.00 kt,以农业源排放为主,其中农田生态系统氨排放量最高,达到36.06 kt,并以氮肥施用贡献最大(87.12%);其次是禽畜养殖,占到人为源氨排放总量的29.44%.非农业源中废物处理和人体排放源贡献最大,分别占到非农业源氨排放量的44.07%和28.49%. 2017年杭州市氨排放量最高,占浙江省氨排放总量的17.83%;但嘉兴市的氨排放强度最大,达到3.82 t·km~(-2).从空间分布来看,氨排放量主要集中在浙江省北部和东南部,而浙江省北部和东北部的氨排放强度相对较高. 相似文献
154.
建立包括食品/饲料,氮肥,大气沉降和生物固氮4部分的人类活动净氮输入模型(NANI),采用单因素方差分析法(one-way ANOVA)和灰色关联度法,研究2006~2016年三峡库区人类活动净氮输入估量的时空分布、组成特征及其贡献率、影响因素.结果表明:(1)三峡库区的NANI估量存在明显的时空差异特征,从2006年的10715.2kg/(km2·a)到2016年的11974.1kg/(km2·a),整体呈现先线性上升后下降的年际变化趋势,以及库首,库尾高,库区腹地低且南部高,北部低的空间分布特征.(2)三峡库区的NANI的组成中,氮肥施用量所占比重最大为50%~56%,是主要输入源,其次是大气氮沉降量,所占比重为22%~24%;相关性分析中,氮肥施用量与NANI相关性最强,R2达到了0.81(P<0.0001).(3)人口密度,粮食产量,农业生产总值和地区生产总值等与NANI的关联度均较高,分别为0.901,0.867,0.794,0.689,NANI值随人口密度的增大而增大,但当人口密度到达一定值(500人/km2)时,其值不再变化;NANI值随着耕地面积的增加而增大,随着森林面积的增加而减小. 相似文献
155.
基于土地利用与景观格局的生态保护红线生态系统健康评价方法——以南京市为例 总被引:1,自引:0,他引:1
生态保护红线是生态功能极其重要或生态环境极为敏感/脆弱的区域,是生态保护的核心区域。以南京市生态保护红线为研究对象,基于2000年、2005年、2010年和2015年四期土地利用/覆被和遥感影像等数据资料,对生态保护红线的生态系统健康进行了评价。结果显示:(1)2015年南京市生态保护红线内不同类型土地利用面积由大到小依次为:林地、耕地、水域、人工表面、湿地和草地,其中林地面积最大并逐年增长,耕地面积逐年减少;(2)2000—2015年南京市生态保护红线生态系统健康指数平均值为53.83,生态保护红线的生态系统健康指数处于亚健康水平,并呈现缓慢增长的趋势;(3)陆域生态系统,特别是森林植被覆盖度较大的区域,生态系统健康指数较高,相反,水域生态系统的生态系统健康指数相对较低。 相似文献
156.
Understanding the ecological trends of the relict habitats in the Luoshan Nature Reserve (LNR) has an important role in the persistence of endangered species and the socio‐economic sustainability in the Ningxia section of the arid desertification belt in North China. Based on data from the Landsat Multispectral Scanner (MSS)/Thematic Mapper (TM)/Enhanced Thematic Mapper Plus (ETM+)/Operational Land Imager (OLI) sensors (from 1977 to 2017), the MODIS normalized difference vegetation index (NDVI) and net primary productivity (NPP) (from 2000 to 2017), the Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM), annual average air temperature and precipitation (from 1977 to 2017), typical anthropogenic factors (population size, cultivated land and residential area) and natural ecological elements (MSS/TM/ETM+/OLI/MODIS NDVI and NPP) were quantitatively contrasted and analyzed for potential correlations. Some indicators of human activities, ecological processes and landscape geography have changed in the LNR. The proportion of residential area increased 3.09‐fold from 1977 to 2017. The population increased 34.30‐fold due to ecological immigration policy implementation in the Hongsipu immigration district. Before immigration, cultivated land increased, but after immigration, this land decreased quickly. Most of the dry‐cultivated land was converted through afforestation and a small part of the land was converted to irrigate cultivation land. We conclude that natural evolution led to the ecological relics, the isolated management to the LNR has objectively created an ecological island that will accelerate inbreeding depression and reduce biodiversity. 相似文献
157.
Sunday Adekunle Adebanjo Lukuman Adekilekun Jimoda Abass O. Alade Adejoke Oluseyi Alamu 《环境质量管理》2019,29(1):63-76
The total particulate matter (PM) deposited within 17 selected industrial areas in Lagos state during the dry season (December 2015 to January 2016) was studied. Deposition gauges measuring 0.2 meters (m) in diameter by 0.15 m in depth were placed at the sampling locations for a period of one month to collect the total deposited PM. The PM was then characterized using energy‐dispersive X‐ray florescence (EDXRF). The sources of the heavy metals were evaluated using enrichment factor (EF) analysis. Factor analysis (FA) was then used to determine the correlations between the identified heavy metals. Twenty‐three elements—sodium (Na), silicon (Si), phosphorous (P), sulfur (S), chlorine (Cl), potassium (K), calcium (Ca), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), germanium (Ge), arsenic (As), strontium (Sr), zirconium (Zr), lead (Pb), tungsten (W), polonium (Po), and actinium (Ac)—were characterized in the PM collected at the sampling sites. The iron elemental ratio ranged from 0.0003 to 3.8848. The EF ranged from 0.0015 to 1697.47, including at the control location. The FA, using principal component analysis techniques, revealed seven factor loadings with 90.03% cumulative, which suggests that the sources are anthropogenic, such as from industrial activities, vehicular emissions, and the combustion of fuel. 相似文献
158.
利用气溶胶-气候耦合模式BCC_AGCM2.0.1_CUACE/Aero,模拟了1850~1980和1980~2010年PM_(2.5)及其人为和自然气溶胶柱含量的时空变化,并分析了人为和自然气溶胶对这种变化的贡献.结果表明:1850~1980年,大部分陆地范围人为PM_(2.5)的柱含量有所增加,尤其是北美东部、欧洲和中国东部等地区,人为PM_(2.5)增加地更明显,且以夏季最为明显;自然PM_(2.5)的变化主要分布在几大沙漠地区,以春、夏季最为显著;人为气溶胶对总PM_(2.5)变化的贡献在秋季最大,达94%,夏、冬季次之,分别为46%和41%,春季最小,仅占28%.1980~2010年,人为PM_(2.5)在东亚、东南亚等地区均有所增加,春夏季较为显著,在欧洲中部和北美东部有所减少,且以夏季减少最为明显;自然PM_(2.5)在沙漠地带有显著的变化,以春季最为明显;人为PM_(2.5)的变化对总变化的贡献相比之前有所减少,四季均小于50%. 相似文献
159.
160.
Takahashi Akira Fukuda Keisuke Tsuji Kiyoshi Yoshikawa Kunio 《Water, Air, & Soil Pollution: Focus》2003,3(5-6):79-88
To evaluate the influence of anthropogenic emission of HCl on the air quality in the Kanto district of Japan, the atmospheric budgetof non-seasalt Cl (nssCl) was analyzed. The Kanto district, which consists of the Tokyo metropolis and the six surrounding prefectures, is the most densely populated region in Japan. The emission intensity of HCl is extremely high compared with those in other regions and most western countries. In this study, the annual wet and dry depositions of nssClwere estimated on a 0.25 × 0.25° grid over the Kanto district based on the concentration monitoring resultsand meteorological data. The budget analysis was conducted by comparing the estimated deposition with the emission of HCl. As a result, the annual total (wet + dry) deposition of nssCl was estimated to be 32 kt yr-1, which closely agreed with HCl emission (36 kt yr-1) from waste incineration in this area. The result suggested that the anthropogenic emission of HCl had a significant influence on the air quality and the deposition of acidity in this area. 相似文献