Monitoring seasonal distribution of an endangered anadromous sturgeon in a large river using environmental DNA

Monitoring dynamic distribution is crucial to conservation management of anadromous sturgeons, but traditional survey methods are less efficient for low-density populations in a large river. Natural propagation of Chinese sturgeon has been monitored annually mainly at the spawning ground using netting for eggs and hydroacoustics for broodstock. However, absence of spawning was observed sporadically in recent years, indicating further crises for the declining population. We analyzed eDNA of water samples collected from 24 sites across 1360 km of the migratory route of anadromous Chinese sturgeon in the middle and lower reaches of the Yangtze River. Chinese sturgeon was detected at 9 sites during the spawning season and 14 sites after the spawning season. We found that positive eDNA detection rates remained constant in the middle reaches but dramatically changed in the lower reaches, reflecting seasonal migration pattern of Chinese sturgeon. Invasive sturgeons were detected in the river, indicating their possible escape from aquaculture facilities. This study established a protocol for the use of eDNA to monitor distribution of Chinese sturgeon and could be valuable in making better policies for the conservation of this endangered species.     

引导企业节能的政策选择模型研究

作为经济主体的企业既是能源和资源的主要消耗者。又是环境污染的主要排放源。因此。有利于节约能源、减少污染的企业节能成为实现社会、经济和生态可持续发展的根本途径。然而，我国企业节能管理和节能市场处于初级阶段。企业节能工作进展缓慢,企业的节能成本远远大于所能获得的收益，因此缺乏主动节能动力，如何选择并建立有效引导企业节能的政策模式成为政府亟待解决的问题。为此。结合现有节能政策。在政府与企业之间进行完全信息动态博弈分析，然后，依据当前企业整体的节能管理状态以及节能市场的发展程度。构建出有效引导企业节能的政策选择模型．进而为政府制定行之有效的节能政策提供理论依据和具体建议,以推动中国节能战略的实施，促进节能目标的实现。     

近20年我国农村自然灾害救济拨款时空变化规律分析

以人均相对灾害救济强度为指标，利用ＥＯＦ方法分析了１９７８～１９９４年我国农村救灾款发放的时空分异规律，发现其５种主要空间分布形式；在东部地区，１９８４年以前华北救灾强度较东北和江南相对偏大，以后则相反。     

从炼厂含油污泥中回收油及残渣无害化治理的研究

通过对某油田石化厂的含油污泥中回收油及其残渣无害化治理问题的研究，确定了用热洗加离心分离实现污油回收及残渣无害化。根据实验室数据，处理此种含油污泥可达到如下结果：油回收率９５％，残渣中油及主要污染物含量基本符合ＧＢ４２８－８４标准，工艺污水符合进入污水场的要求。采用此法，按照２ｔ／ｈ的处理量计算，预计设备投资４５．７万元。     

新型机车监控系统的研究

设计了一种基于GSM的机车监控系统。用无线电手机传输监控装置产生的原始数据至PC机 ,来达到实时监控机车运行状况的目的。实践表明 ,该系统简单灵活 ,传输可靠 ,具有良好的稳定性和可靠性。与现行车载监控装置相比 ,新型机车监控系统具有提高数据的实时性、减轻工作人员的劳动强度等优点     

Long-Term Effects of Fertilization on Soil Organic Carbon Changes in Continuous Corn of Northeast China: RothC Model Simulations

Soil organic C (SOC) content can increase by managing land use practices in which the rates of organic C input exceed those of organic C mineralization. Understanding the changes in SOC content of Black soils (mainly Typic Halpudoll) in northeast China is necessary for sustainable using of soil resources there. We used the RothC model to estimate SOC levels of Black soils under monoculture cropping corn in a long-term fertilization trial at Gongzhuling, Jilin Province, China. The model outputs for the changes in SOC were compared with measured data in this long-term fertilization/manure trial. The sound performance of model in simulating SOC changes suggests that RothC is feasible with Black soils in the temperate climatic region of northeast China. The modeled and measured results indicated that the treatment without fertilizer/farmyard manure (FYM) addition led to a continuous decline in SOC during the study period and N and NPK fertilization were inadequate to maintain the SOC levels in the plow layer (upper 20 cm) unless FYM was added under the current conventional management associated with no above-ground crop residues returning into the soil. Soil organic carbon could follow the same path of decline if the same management practices are maintained. Model results indicate that returning above-ground crop residues to the soil from 2002 to 2022 would increase SOC by 26% for the treatment without fertilization addition, 40% for N treatment, 45% for NPK treatment, and 38% and 46% for N and NPK treatments with FYM addition, compared to the levels in the corresponding treatments in 2002. The simulation results suggest that the RothC model is a feasible tool to assess SOC trend under different management practices, and returning above-ground crop residues into the soil would lead to a remarkable increase in SOC of Black soils in the region.     

Coupled oxidation of aromatic hydrocarbons by horseradish peroxidase and hydrogen peroxide

The oxidation capability of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) coupled oxidation of aromatic hydrocarbons (o-xylene-d10 and naphthalene-d8) was investigated. Batch experiments were conducted using horseradish peroxidase prepared in potassium phosphate buffer in the presence of H2O2. The oxidation of aromatic hydrocarbon was tested as a function of HRP at a fixed concentration of H2O2, and as a function of the concentration of H2O2 at a constant HRP activity (4000 units/ml). The mass removal of o-xylene-d10 and naphthalene-ds increased with increasing HRP enzymatic activity, and up to 54% and 51% of mass removal were observed for o-xylene-d10 and naphthalene-d8, respectively. Increasing the concentration of H2O2 resulted in increased mass removal of aromatic hydrocarbons.