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81.
长江口湿地资源生物的可持续利用   总被引:9,自引:1,他引:9  
长江口湿地是我国一块重要的滨海湿地,蕴含了丰富的自然资源,这些自然资源为当地乃至更广领域的经济发展都作出了重要的贡献。本文主要探讨该湿地生态系统中六种具有代表性资源生物的利用现状。这六种资源生物是中华绒螯蟹苗、日本鳗鲡苗、缢蛏、河蚬、芦苇和海三棱草。它们在维持河口生态系统的稳定性和连续性上具有其他许多生物所不可替代的作用。目前由于种种原因,这些资源的持续发展已受到了一定的威胁,造成它们资源现存量下降的主要原因是过度捕捞、受污严重及围垦滩涂等一些因素。如何正确利用和保护这些资源已是一项急待解决的问题,针对这些问题为可持续利用它们提出了一些相应的对策和建议。  相似文献   
82.
A glasshouse pot experiment was conducted to study the effect of arbuscular mycorrhizal (AM) colonization by Glomus mosseae BEG167 on the yield and arsenate uptake of tomato plants in soil experimentally contaminated with five As levels (0, 25, 50, 75 and 150 mg kg(-1)). Mycorrhizal colonization (50-70% of root length) was little affected by As application and declined only in soil amended with 150 mg As kg(-1). Mycorrhizal colonization increased plant biomass at As application rates of 25, 50 and 75 mg kg(-1). Shoot As concentration increased with increasing As addition up to 50 mg kg(-1) but decreased with mycorrhizal colonization at As addition rates of 75 and 150 mg kg(-1). Shoot As uptake increased with mycorrhizal colonization at most As addition levels studied, but tended to decrease with addition of 150 mg As kg(-1). Total P uptake by mycorrhizal plants was elevated at As rates of 25, 50 and 75 mg kg(-1), and more P was allocated to the roots of mycorrhizal plants. Mycorrhizal plants had higher shoot and root P/As ratios at higher As application rates than did non-mycorrhizal controls. The soil of inoculated treatments had higher available As than uninoculated controls, and higher pH values at As addition levels of 25, 50 and 75 mg kg(-1). Mycorrhizal colonization may have increased plant resistance to potential As toxicity at the highest level of As contamination studied. Mycorrhizal tomato plants may have potential for phytoextraction of As from moderately contaminated soils or phytostabilization of more highly polluted sites.  相似文献   
83.
This study investigated a combined low-thermal and CaO2 pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO2/g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.  相似文献   
84.
Environmental Science and Pollution Research - The present study sought to determine the effects of multi-walled carbon nanotubes (MWCNTs) concentrations (0–10 mg L?1) on tetracycline...  相似文献   
85.
Nie  Wen  Guo  Lidian  Yu  Hai  Liu  Qiang  Hua  Yun  Xue  Qianqian  Sun  Ning 《Environmental science and pollution research international》2022,29(49):74097-74117

During the excavation of high gas mine, gas and dust often exist at the same time. In order to ensure that the gas concentration remains within a safe range and minimize the risk of workers’ pneumoconiosis, we simulated the interaction mechanism of airflow, gas, and dust, explored the pollution law of gas and dust, and obtained the optimal purification distance (Lp) by the CFD method. The reliability of the numerical simulation was verified by field measurements. Firstly, the properties of the gas and dust affected the structure of the airflow field. At the same time, the change in the airflow field affected the concentration distributions of the gas and dust. During the diffusion process, some high-risk regions in which the gas or dust concentrations exceeded 0.80% or 200 mg/m3, respectively, were discovered. Moreover, we have found that the airflow velocity in the top region of the tunnel and at the intersection corner between the cutting face and tunnel wall was the main factor affecting the purification effects. When Lp = 5–8 m, the gas concentration remained below 0.50%. When Lp = 6 m, the dust concentration reached a minimum of 287.5 mg/m3. Therefore, the optimal purification distance was determined to be 6 m; in which case, the gas and dust concentrations decreased by 32.84% and 47.02%, respectively.

  相似文献   
86.
Chao  Ling  Sun  Yajun  An  Zhen  Li  Juan  Wu  Weidong  Liu  Yue  Song  Jie 《Environmental science and pollution research international》2022,29(11):15999-16005
Environmental Science and Pollution Research - Previous studies have reported regional variations in the relationship between ambient temperature and dermatitis, which therefore remain...  相似文献   
87.

China launched the One Belt & One Road (OBOR) initiative to minimize the energy resource shortage. The China’s nearby countries are rich in energy resources especially Middle East and North Africa (MENA) and Asian countries which make them ideal locations to cooperate with China in terms of energy resources, as 42.8% of world energy consumption belongs to OBOR countries. The present study elaborates the spatial distribution pattern of energy consumption disparities and its impact on environment. To do this, an entropy approach is utilized to compute the energy consumption inequalities in OBOR and its regions. The spatial and Pareto analysis show that MENA, East, and Southeast Asian economies have the highest degree of energy consumption inequalities, while European and Central Asian economies show the lowest energy consumption inequalities in OBOR region. The long-run estimates indicate that energy consumption inequalities enhance the CO2 emission in OBOR and its region except South and Southeast Asia. Financial development also has a significantly positive impact on CO2 emission in all models for OBOR and its regions except East Asia. Based on findings, the spatial distribution analysis is applicable to maintain balance in regional energy consumption inequality within OBOR and its regions.

  相似文献   
88.
Environmental Science and Pollution Research - VUV/UV photodegradation technology, which is free of catalysts or oxidants, has been regarded as an efficient method to decompose gaseous VOCs....  相似文献   
89.
Wu YJ  Leng XF 《Chemosphere》2000,41(1-2):183-186
The activities of calcium-activated ATPase (Ca2+-ATPase) and calcium magnesium-activated ATPase (Ca2+-Mg2+-ATPase) in the shell gland, and concentrations of 17beta-estradiol (E2) and progesterone in serum were monitored, respectively, from hens orally dosed with tri-o-cresyl phosphate (TOCP) (750 mg/kg). Treated birds were monitored daily for laying and development of delayed neurotoxicity, and activities of Ca2+-ATPase and Ca2+-Mg2+-ATPase were measured at 7 and 10 days after dosing. TOCP-treated birds manifested motor deficit by 7-9 days postdosing, while hens administered vehicle exhibited no signs of delayed neurotoxicity. Ca2+-ATPase and Ca2+-Mg2+-ATPase activities of shell glands from TOCP-dosed hens were not significantly affected (P > 0.05). The serum E2 concentration was significantly reduced in TOCP-treated hens (P < 0.01); however, progesterone levels were unaffected.  相似文献   
90.
Replacement of H2O2 by O2 in Fenton and photo-Fenton reactions   总被引:8,自引:0,他引:8  
Utset B  Garcia J  Casado J  Domènech X  Peral J 《Chemosphere》2000,41(8):1187-1192
The consumption of oxygen during the degradation of aniline by Fenton and photo-Fenton reactions is studied. The effect that parameters like aniline, Fe(II) and H2O2 initial concentration, pH, temperature and O2 flow rate have on the ratio O2 consumed/H2O2 consumed is examined. The determination of those combinations of experimental conditions for which an effective partial replacement of H2O2 by O2 as electron acceptor takes place is investigated. The results show that this replacement takes place in a variable extent, but the presence of H2O2 is necessary along the reaction, and the maximum consumption of O2 only takes place when the ratio amount of aniline mineralized vs. initial aniline concentration is minimal.  相似文献   
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