中国降水酸度预测模型

利用逐步多元线性回归方法建立了中国降水酸度预测模型。该模型包括：大气中二氧化硫、氮氧化物和总悬浮颗粒物的浓度、单位面积二氧化硫排放量这四个时间和空间变量;地理位置横向坐标、降雨量和辐射强度这三个空间变量。该模型通过回顾检验具有较好的预测精度并在假设未来中国环境状况的基础上,对降水酸度的分布进行了预测。该模型是在地理信息系统工具软件ARC/INFO支持下运行的,其预测方法及结果具有空间特性。     

多维电极法处理高色度活性染料模拟废水影响因素分析

以活性嫩黄K 4G染料模拟废水为处理对象 ,采用多维电极法 ,考查了各种因素对多维电极系统处理活性染料时的脱色率、CODCr降解率的影响 ,结果表明 ,增多活性炭量、增大电流密度、延长电解时间和加入铁屑 ,都能使脱色率和CODCr降解率得到提高 ,电导率的变化对脱色率和CODCr降解率有一定影响。利用正交实验比较了各因素的相对影响大小     

生态环境空间数据的多尺度集成方法

空间数据集成是解决异构网络环境信息系统间空间数据交换、传输和共享、数据互操作的有效方法。笔者在分析生态环境数据特征和生成机理以及集成原理基础上 ,提出了生态环境空间数据的空间多尺度集成方法 ,并构建了基于面向应用目标的生态环境空间数据集成系统框架和运行过程机制。 更多还原      

PREDICTABILITY OF SURFACE WATER POLLUTION LOADING IN PENNSYLVANIA USING WATERSHED‐BASED LANDSCAPE MEASUREMENTS1

ABSTRACT: We formally evaluated the relationship between landscape characteristics and surface water quality in the state of Pennsylvania (USA) by regressing two different types of pollutant responses on landscape variables that were measured for whole watersheds. One response was the monthly exported mass of nitrogen estimated from field measurements, while the other response was a GIS‐modeled pollution potential index. Regression models were built by the stepwise selection protocol, choosing an optimal set of landscape predictors. After factoring out the effect of physiography, the dominant predictors were the proportion of “annual herbaceous” land and “total herbaceous” land for the nitrogen loading and pollution potential index, respectively. The strength of these single predictors is encouraging because the marginal land cover proportions are the simplest landscape measurements to obtain once a land cover map is in hand; however, the optimal set of predictors also included several measurements of spatial pattern. Thus, for watersheds at this general hierarchical scale, gross landscape pattern may be an important influence on instream pollution loading. Overall, there is strong evidence that using landscape measurements alone, obtained solely from remotely sensed data, can explain most of the water quality variability (R²= approx. 0.75) within these watersheds.     

EFFECTIVE USE OF LANDSAT DATA IN HYDROLOGIC MODELS1

ABSTRACT: In a cooperative demonstration project, NASA and the U.S. Army Corps of Engineers (Corps) compared conventional and Landsat-derived land-use data for use in hydrologic models, and the resulting discharge frequency curves were analyzed. When a grid-based data-management system was used on a cell-by-cell basis (size about 1.1 acres or 0.45 hectare), Landsat classification accuracy was only 64 percent, but, when the grid cells were aggregated into watersheds, the classification accuracy increased to about 95 percent. When both conventional and Landsat land-use data were input to the HEC-1 model for generating discharge frequency curves, the differences in calculated discharge were judged insignificant for subbasins as small as 1.0mi² (2.59 km²). For basins larger than 10mi² (25.9km²), use of the Landsat approach is more cost-effective than use of conventional methods. Digital Landsat data can also be used effectively by local and regional agencies for hydrologic analysis by incorporating the data into grid-based data-management systems. The transfer of this new technology is well under way through inclusion in some Corps training courses and through use by both county government personnel and private consultants.     

利用计算机技术编制多媒体环境质量报告书

利用计算机技术编制多媒体声像环境质量报告书，具有三维图像、全程多媒体自动播放坐标图动态显示、生动活泼、声图并貌的特点。     

An evaluation of grid size uncertainty in empirical soil loss modeling with digital elevation models

This paper presents a study on the effect of topographic variability on grid-based empirical estimation of soil erosion and sediment transport with raster geographic information systems (GIS). An original digital elevation model (DEM) of 10 m resolution for a case watershed is resampled to six realizations of greater grid sizes for a comparative examination. The Universal Soil Loss Equation (USLE) and a distance-based sediment delivery equation are applied to the watershed to calculate soil loss from each cell and total sediment transport to streams, respectively. The results suggest that the selection of the DEM gird size has considerable influence on the soil loss estimation with the empirical models. The estimate of total soil loss from the watershed decreases significantly with the increasing DEM cell size as the spatial variability is reduced by the cell aggregation. The empirical modeling approach is a useful tool for qualitative assessment of soil erosion, provided that spatial variability can be adequately represented by applied DEMs. However, discretion is suggested for its applications to quantitative estimation of soil loss concerning the sensitivity to the grid size selection.     

中国森林植被生物量空间网格化估计

森林是陆地生态系统的重要碳库之一,在全球碳循环中发挥着巨大作用。森林生物量是核算森林碳储量的主要因子,其数量及空间分布是评估森林生态系统碳汇潜力的重要参数。论文以中国第8次森林资源清查资料为基础,以影响森林生物量空间分布的气候（气温、降水）、地形（高程、坡度）和植被因子（NDVI）为辅助,利用降尺度方法估算了1 km×1 km格网分辨率下的中国森林生物量,并从不同空间尺度对研究结果进行了验证。结果表明：1）中国森林生物量总量约为13.56 Pg,平均生物量密度为65.3 t/hm²,各省森林生物量总量差异较大,总量较高省份主要集中于西南和东北内蒙古地区,其中西南地区（西藏、四川、云南）最高,为4.5 Pg,占总量的33%;东北内蒙古地区（黑龙江、吉林、辽宁、内蒙古）次之,为3.58 Pg,占总量的26%;2）在省级尺度构建的森林生物量与相关影响因子的回归关系可用于栅格尺度下森林生物量的降尺度估算,多尺度验证分析表明网格化估算结果基本合理;3）中国森林生物量空间格局区域分异规律明显,大致以东北至西南为界,与水热条件空间分布格局基本一致,生物量高值区主要集中于东北地区（大小兴安岭、长白山地区）、西南地区（横断山脉）、新疆山区（阿尔泰山、天山、昆仑山）、秦岭和东南武夷山等地区。     

高压电网大气腐蚀在线监测技术进展

针对高压电网输变电设备的大气腐蚀问题,研究了几种典型的大气腐蚀监测技术。基于文献分析,探讨了电偶腐蚀电池、电化学阻抗谱、薄膜电阻传感器、石英晶体微天平以及交流导纳等腐蚀在线监测技术的研究进展,并对比分析了各种监测技术在电力设备中应用的优缺点。采用薄膜电阻探针和交流导纳技术可以实现高压输变电塔、架空地线以及变压设备大气腐蚀的在线监测。对输变电设备的大气腐蚀实施自动化在线监测,可以为设备安全诊断提供重要依据,与大数据分析结合,还可以为故障诊断与寿命评估提供参考。     

大气环境热点网格遥感筛选方法研究

为筛选京津冀及周边地区的大气环境热点网格,在卫星遥感反演获取区域灰霾天数、PM_2.5、NO₂和SO₂浓度等大气环境四项遥感监测因子的基础上,首先利用分形求和模型确定了研究区域的四项指标的背景值和标准值,然后根据ORAQI计算方式提出一种大气环境遥感综合污染指数,并提取了大气环境热点网格,最后结合高分辨率卫星数据对热点网格的工业用地情况进行初步探讨分析.结果表明,2016年京津冀及周边地区各项大气污染物的局部分布特征表现出较大差异,不同地区的主要污染物不尽相同并且呈多项污染物复合污染的特征,利用分形统计模型确定灰霾天数、PM_2.5、NO₂和SO₂浓度的背景值分别为10.7d、57.5μg/m³、515.7×10¹³mole/cm²和0.29DU,标准值分别为22.2d、112.2μg/m³、2073.1×10¹³mole/cm²和0.64DU.大气环境遥感综合污染指数表明大气环境综合污染相对最重的地区主要分布在保定中部、石家庄中北部及邢台南部和邯郸北部交界处,该区域共筛选出1782个大气环境热点网格,其中工业用地面积占比较低的网格单元比例相对较大,这表明小型企业生产排放对当地的大气环境质量影响较大.