Application of artificial neural network approach and remotely sensed imagery for regional eco-environmental quality evaluation

Eco-environment quality evaluation is an important research theme in environment management. In the present study, Fuzhou city in China was selected as a study area and a limited number of 222 sampling field sites were first investigated in situ with the help of a GPS device. Every sampling site was assessed by ecological experts and given an Eco-environment Background Value (EBV) based on a scoring and ranking system. The higher the EBV, the better the ecological environmental quality. Then, three types of eco-environmental attributes that are physically-based and easily-quantifiable at a grid level were extracted: (1) remote sensing derived attributes (vegetation index, wetness index, soil brightness index, surface land temperature index), (2) meteorological attributes (annual temperature and annual precipitation), and (3) terrain attribute (elevation). A Back Propagation (BP) Artificial Neural Network (ANN) model was proposed for the EBV validation and prediction. A three-layer BP ANN model was designed to automatically learn the internal relationship using a training set of known EBV and eco-environmental attributes, followed by the application of the model for predicting EBV values across the whole study area. It was found that the performance of the BP ANN model was satisfactory and capable of an overall prediction accuracy of 82.4%, with a Kappa coefficient of 0.801 in the validation. The evaluation results showed that the eco-environmental quality of Fuzhou city is considered as satisfactory. Through analyzing the spatial correlation between the eco-environmental quality and land uses, it was found that the best eco-environmental areas were related to forest lands, whereas the urban area had the relatively worst eco-environmental quality. Human activities are still considered as a major impact on the eco-environmental quality in this area.     

环境管理、规划管理与项目管理

文章从深入分析环境管理的内涵出发,进而提出树立项目管理意识,强化项目管理的概念,说明项目管理在环境管理中的地位和作用,从这个意义上讨论环境管理与项目管理的关系,简述环境保护项目管理的主要环节,达到提高环境管理效能的途径的目的。     

柚园间种作物及施用不同有机肥对土壤与柚果的影响

柚树间种短期经济作物在提高柚园经济效益的同时,还可提高土壤的有机质和N、P、K养分质量分数,改善柚园小区气候,增加有机肥来源。间种物残余体作为绿肥,可显著地提高柚果产量和质量。     

Metals in Feathers of Bonin Petrel, Christmas Shearwater, Wedge-Tailed Shearwater, and Red-Tailed Tropicbird in the Hawaian Islands, Northern Pacific

Levels of environmental pollutants are usually higher in mainland and coastal areas than in offshore or oceanic islands due to higher inputs from agricultural and industrial sources. Levels of heavy metals are usually higher in adult than in young birds, because they have had longer to accumulate metals in their tissues, and/or because they may eat larger, more contaminated, prey. We examined the levels of arsenic, cadmium, chromium, lead, manganese, mercury, and selenium in the adults and young of Bonin petrel (Pterodroma hypoleuca), Christmas shearwater (Puffinus nativitatis) and red-tailed tropicbird (Phaethon rubricauda) on Midway Atoll, and adult wedge-tailed shearwater (Puffinus pacificus) on Midway Atoll and on Manana Island (off Oahu) in the northern Pacific. All birds were analyzed individually except for Christmas Shearwater chicks where samples were pooled to obtain sufficient quantities for analysis. Significant (p<0.05) age-related differences were found for mercury, selenium, manganese and chromium in Bonin petrels, for selenium and mercury in Christmas shearwaters, and for chromium and mercury in Red-tailed Tropicbirds. Lead approached significance for all three species. Adults had higher levels than young except for chromium and manganese in the petrels and arsenic in all three species. There were significant interspecific differences in concentrations of all metals except arsenic for the adults nesting on Midway. Christmas shearwaters had the highest levels of all metals except mercury and chromium. Bonin petrels, the smallest species examined, had mercury levels that were over three times higher than any of the adults of the other three species. For wedge-tailed shearwaters, levels of chromium and lead were significantly higher, and manganese and selenium were lower on Midway than Manana. Knowledge of the foraging ranges and habits of these far-ranging seabirds is inadequately known, but does not currently explain the observed differences among species. We could not find a consistent pattern of differences between the burrow nesting species (Bonin petrel, Wedge-tailed shearwater) and the surface nesting tropicbirds. There was no consistent pairwise correlation between any metals across all species.     

室内空气品质评价系统研究

本文提出了进行室内空气品质评价的一个系统,其中的评价方法选用综合评价方法。     

基于热带海洋大气环境下机载PCB板的环境适应性对比研究

目的 通过机载PCB板(Printed Circuit Board,PCB)在热带海洋大气环境下的腐蚀老化特征和电气性能退化规律分析,研究其在热带海洋大气环境下的环境适应性。方法 根据热带海洋大气环境中PCB板的实际使用环境大多为舱室内部封闭或半封闭的情况,分别设计并开展海南万宁海洋平台棚下暴露场和某海域环境户外简易遮蔽玻璃框下3 a的自然环境试验。结果 PCB板的焊点、焊盘、印制导线以及引线头等部位在2种试验环境中均出现了不同程度的腐蚀破坏,试验后期,所有部位的腐蚀程度全部达到了4级,导通电阻从几十毫欧增大至几十兆欧,绝缘电阻从10 GΩ以上降低至几兆欧。结论 在万宁站试验2 a和某海域试验3 a后,PCB板均不满足耐电压的技术要求(500 V交流电压60 s),万宁海洋平台棚下暴露场对PCB板的环境适应性更为严酷。     

海南西沙试验站大气霉菌群落初步调查

目的 筛选西沙试验站大气环境优势菌种,进行西沙试验站装备敏感菌研究。方法 采用撞击法进行大气霉菌采样,用统计学法计算出不同试验场地真菌数量,结合形态学法与ITS1-5.8S-TIS2或26SrDNA D1/D2区序列分析法鉴定菌种,并用SPSS初步探讨大气真菌与环境因素的关系,分析西沙试验站装备敏感菌。结果 西沙试验站优势种为Aspergillus aculeatus、Penicillium citrinum、Pithomyces sacchar、变红镰孢霉Fusarium incarnatum、Cladosporium oxysporum和Cladosporium oryzae,影响西沙试验站大气霉菌群落结构的重要环境因素是相对湿度和风速,贮存在西沙试验站的装备容易长霉,多种材料有不同的敏感菌,尤其是涂层样件和橡胶类材料。结论 西沙试验站大气环境中存在种类繁多的霉菌。     

空空导弹海洋大气自然环境试验研究

针对空空导弹随航母服役需求和海洋大气自然环境适应性风险,结合相关标准和研制经验,对空空导弹海洋大气自然环境试验方案设计流程、方法及要点进行了研究。提出了一套空空导弹海洋大气自然环境试验方案,可用于指导新研型号科学有效地开展自然环境试验,为回答空空导弹海洋大气自然环境适应性指标提供了支撑。空空导弹应系统策划海洋大气自然环境试验,以尽早暴露问题,实现产品设计改进,为上舰环境适应性的提高奠定基础。同时,还应大力开展自然加速环境试验技术和动态自然环境试验技术研究工作。     

新形势下航天装备环境试验技术的未来发展趋势

从航天装备面临的实战化考核、数字化建设和低成本控制等新形势与新要求出发,梳理了环境试验技术在航天装备试验鉴定中存在的实战化考核能力不足、全寿命周期环境效应考核不充分等技术难题,结合航天装备环境试验的国内外发展现状,系统分析了航天装备环境试验技术的未来发展趋势,试验环境综合化、试验设计一体化、试验手段数字化在提升航天装备环境试验水平、缩短装备试验周期、降低试验成本方面具有显著优势,也是航天装备环境试验未来发展的重要方向。     

舰船环境适应性设计方法探索与实践

探索舰船环境适应性的设计方法,以提高舰船在各种复杂环境下的适应能力。分析了舰船环境适应性设计中面临的若干问题和改进提高方向,参考借鉴国内外航空航天、电子等行业成功经验,提出了指导舰船环境适应性设计的主要设计原则和工作内容。围绕改善环境条件、加强耐环境能力设计这2个方面,提出了3种环境适应性设计方法,包括基于规范的设计方法、基于环境仿真的设计方法、基于预使用验证的设计方法。根据舰船风浪环境适应性设计的特点和要求,选择采用环境仿真和模型试验技术开展了应用研究。基于分析结果,提出了增加水线面系数、调整浮心、优化线型等多项改进措施建议。采用环境仿真和模型试验相结合的方式,可有效支撑舰船风浪环境适应性设计和评估,这一方法具有较高的工程推广应用价值。另外,未来应加大环境仿真技术的研究和应用力度,尝试开展多因素综合环境仿真,以进一步提高舰船的环境适应性。