Spatial analysis of resources and environmental carrying capacity in Iran

Urbanization and mass movement of the population from rural areas and small cities to megacities have led to environmental, economic, and social problems in Iran. In dealing with these challenges, assessing resource and environmental carrying capacity (RECC) is considered an effective method to leverage space and capital to achieve sustainable development. This study aimed to rank the provincial RECC in Iran. Toward this purpose, environmental indices were generated from remotely sensed and statistical census data. Then, the provinces were scored in terms of environmental, economic, and infrastructural carrying capacities, and RECC using the mean variance analysis method. Results demonstrated that in most areas, there is no relationship between economic and infrastructural capacities and development. Statistically, a correlation coefficient of −0.53 between economic and environmental carrying capacities indicated excessive use of environmental capacities. Moreover, the spatial distribution pattern of environmental, economic, and infrastructural carrying capacity was entirely heterogeneous between the provinces; there was a northeast–southwest pattern in terms of infrastructural capacity and an economic pattern from north to south. The distribution pattern of RECC is most consistent with the environmental capacity, pointing at the high weight of the indicators of the RECC model. In conclusion, this research offers a new vision for policymakers and provides a theoretical and applicable framework for implementing sustainable strategies in land-use planning. It is recommended that the RECC concept and tools can be used not only for planning but also for measuring the efficiency of spatial development programs and establishing land balances in the region.     

基于改进的非线性GM(1,1)模型的职业病预测研究

为了更准确地预测职业病，在传统GM(1,1)模型的基础上，提出改进的非线性GM(1,1)模型，在传统的GM(1,1)模型中引入弱化算子，将紧邻均值与原始数据之间的线性假设改为非线性假设，提高曲线的拟合度。以2005—2014年的全国职业病例数为研究对象，进行数据拟合和预测分析，其中以2014年职业病例数作为验证数据，并利用后验差比值和小误差概率2个参数，检验该改进模型的预测精度。由应用实例的分析结果可知:在职业病发病趋势的预测方面，改进的非线性GM(1,1)模型的预测精度提高到一级，曲线拟合度较高，预测得到2015年的职业病例数为34 900例。     

Degradation of polyacrylamide (PAM) and methane production by mesophilic and thermophilic anaerobic digestion: Effect of temperature and concentration

• PAM degradation in thermophilic AD in comparison with mesophilic AD. • PAM degradation and its impact on thermophilic and mesophilic AD. • Enhanced methane yield in presence of PAM during thermophilic and mesophilic AD. • PAM degradation and microbial community analysis in thermophilic and mesophilic AD. Polyacrylamide (PAM) is generally employed in wastewater treatment processes such as sludge dewatering and therefore exists in the sludge. Furthermore, it degrades slowly and can deteriorate methane yield during anaerobic digestion (AD). The impact or fate of PAM in AD under thermophilic conditions is still unclear. This study mainly focuses on PAM degradation and enhanced methane production from PAM-added sludge during 15 days of thermophilic (55°C) AD compared to mesophilic (35°C) AD. Sludge and PAM dose from 10 to 50 g/kg TSS were used. The results showed that PAM degraded by 76% to 78% with acrylamide (AM) content of 0.2 to 3.3 mg/L in thermophilic AD. However, it degraded only 27% to 30% with AM content of 0.5 to 7.2 mg/L in mesophilic AD. The methane yield was almost 230 to 238.4 mL/g VSS on the 8th day in thermophilic AD but was 115.2 to 128.6 mL/g VSS in mesophilic AD. Mechanism investigation revealed that thermophilic AD with continuous stirring not only enhanced PAM degradation but also boosted the organics release from the sludge with added PAM and gave higher methane yield than mesophilic AD.     

Use of genetic,climatic, and microbiological data to inform reintroduction of a regionally extinct butterfly

Species reintroductions are increasingly used as means of mitigating biodiversity loss. Besides habitat quality at the site targeted for reintroduction, the choice of source population can be critical for success. The butterfly Melanargia russiae (Esper´s marbled white) was extirpated from Hungary over 100 years ago, and a reintroduction program has recently been approved. We used museum specimens of this butterfly, mitochondrial DNA data (mtDNA), endosymbiont screening, and climatic‐similarity analyses to determine which extant populations should be used for its reintroduction. The species displayed 2 main mtDNA lineages across its range: 1 restricted to Iberia and southern France (Iberian lineage) and another found throughout the rest of its range (Eurasian lineage). These 2 lineages possessed highly divergent wsp alleles of the bacterial endosymbiont Wolbachia. The century‐old Hungarian specimens represented an endemic haplotype belonging to the Eurasian lineage, differing by one mutation from the Balkan and eastern European populations. The Hungarian populations of M. russiae occurred in areas with a colder and drier climate relative to most sites with extant known populations. Our results suggest the populations used for reintroduction to Hungary should belong to the Eurasian lineage, preferably from eastern Ukraine (genetically close and living in areas with the highest climatic similarity). Materials stored in museum collections can provide unique opportunities to document historical genetic diversity and help direct conservation.     

Assessing effects of non-native crayfish on mosquito survival

Introductions of non-native predators often reduce biodiversity and affect natural predator–prey relationships and may increase the abundance of potential disease vectors (e.g., mosquitoes) indirectly through competition or predation cascades. The Santa Monica Mountains (California, U.S.A.), situated in a global biodiversity hotspot, is an area of conservation concern due to climate change, urbanization, and the introduction of non-native species. We examined the effect of non-native crayfish (Procambarus clarkii) on an existing native predator, dragonfly nymphs (Aeshna sp.), and their mosquito larvae (Anopheles sp.) prey. We used laboratory experiments to compare the predation efficiency of both predators, separately and together, and field data on counts of dragonfly nymphs and mosquito larvae sampled from 13 local streams. We predicted a lower predation efficiency of crayfish compared with native dragonfly nymphs and a reduced predation efficiency of dragonfly nymphs in the presence of crayfish. Dragonfly nymphs were an order of magnitude more efficient predators than crayfish, and dragonfly nymph predation efficiency was reduced in the presence of crayfish. Field count data showed that populations of dragonfly nymphs and mosquito larvae were strongly correlated with crayfish presence in streams, such that sites with crayfish tended to have fewer dragonfly nymphs and more mosquito larvae. Under natural conditions, it is likely that crayfish reduce the abundance of dragonfly nymphs and their predation efficiency and thereby, directly and indirectly, lead to higher mosquito populations and a loss of ecosystem services related to disease vector control.     

污水处理厂设备维护管理优化研究

以JL污水处理厂设备管理优化过程为例,充分吸取LCC,TPM中的先进思想,以设备运行可靠性及设备维护经济性为追求目标,建立了设备管理优化体系。流程体系上,通过建立作业指导文件,建立标准化维修程序,对于操作过程及时进行记录,建立可视化、可追溯的管理方法;指标体系上,根据设备重要性及运行状况,确定设备风险指数,分级管理;建立控制指标,并动态调整;管控体系上,建立设备“户口”,对设备的维护、保养、使用等信息进行全面登记;考核设备维护的全面性、及时性、可靠性、合规性;重视设备维护的预计与预警;技术体系上,通过设备监测仪器的使用,对设备运行状况定量化。通过不断推进设备预防性维护工作,设备完好率不断提升,仪表完好率从2016年的97.34%,96.55%水平,分别提升至99.08%,98.72%;维护费用也保持在较低水平,检修费与资产比例在实施的前两年分别降至1.49%,0.85%,实现了污水处理厂节能降耗及运行可靠性的强化。     

海洋平台圆柱体坠落运动轨迹及落点分析

传统的角度偏差经验值方法导致落物风险评价过程中的落点和危险区预测存在较大误差，科学化、立体化、完整化、多因素概化的落物轨迹和落点分析方法及工具缺位。为此，以海洋平台圆柱体落物为研究对象开展先导研究，在2D运动理论模型基础上，考虑3维、6度受力与运动参数，引入粘性拖曳力系数经验公式、海流运动、旋转升力和力矩项，建立了具有普适性的落物水下3D运动轨迹预测模型，并以现场实验数据校验表明模型方法可行、结果更可信；据此以Matlab 2016为程序设计平台编制了海洋平台圆柱体坠落运动预测分析工具（MREDP），分析了坠落运动落点分布规律。研究结果表明:随着初始倾斜角度的增大，落点偏移距离呈现先增后降的趋势，于62°时达到最大值，运动轨迹整体呈现螺线曲率减小、向轨迹曲线外开口侧偏移趋势；落点分布变化可分为Y轴偏移稳定主导阶段、X轴偏移实力型快速主导阶段和X轴偏移机会型主导阶段3个阶段；相对MREDP预测结果，DNVGL-RP-F107经验性角度偏差推荐结果较为保守，MREDP可为DNVGL-RP-F107提供更加准确、可信的轨迹曲线和落点取值。基于分析结果，提出了采用Monte Carlo方法表征实际工程中起始运动参数随机性和入水撞击产生的不确定性等建议。     

基于尾涡强度的无人机与民机纵向安全间隔评估研究

为了解决无人机频频入侵机场净空，与民航客机发生危险接近的问题，以碰撞风险为量化指标，对无人机与民机需要保持的纵向安全间隔进行评估研究。分析民机尾涡流场对无人机运行的影响，利用Crow近场涡强度消散理论，得到实际尾迹影响区改进Reich碰撞模板，据此建立CNS/GPS性能环境下的纵向间隔评估模型，通过Matlab进行间隔值求解。研究结果表明:模型可以较为准确地反映民机起飞初始爬升阶段无人机尾随运行时导航性能和尾涡迹对所需最小间隔值的影响，并得到给定安全目标水平的计算结果。     

火灾发生率空间分异及影响因素研究

为了探究我国火灾空间聚集特征与影响因素的空间异质性，采用全局莫兰指数、局部莫兰指数、逐步回归模型、地理加权回归模型、地理探测器方法对我国地级市单元进行研究。研究结果表明:我国火灾发生率具有显著的聚集性；我国火灾发生率较低的“冷点”区域有1个，火灾发生率较高的“热点”区域有4个；人均GDP、城镇居民人均可支配收入、人口密度、年平均气温4 个因素的影响效应具有空间异质性。人均GDP与火灾发生率为正相关，另外3影响因素对火灾发生率的作用表现出正负2种相关关系；2因素交互作用要比单因素作用于火灾发生率时影响力更显著，各影响因素的交互作用类型有非线性增强型和双因子增强型2种。