[Spatio-temporal variations of vegetation cover in semi-arid regions and its response to climate change: A case study of Xilin Gol, Inner Mongolia, China]. / åŠå¹²æ—±åŒºæ¤è¢«è¦†ç›–æ—¶ç©ºå˜åŒ–ç‰¹å¾åŠå ¶å¯¹æ°”å€™å˜åŒ–çš„å“åº”: 以锡林郭勒盟为例.

The quantitative analysis of spatio-temporal variations of vegetation cover and its correlation with climate are of great significance for understanding of ecological environment, ecological civilization construction, and sustainable development in semi-arid areas. We investigated the spatio-temporal variations of normalized difference vegetation index (NDVI) and its response to climate change during 2000-2020 in Xilin Gol, Inner Mongolia, by using trend analysis, regression analysis and partial correlation analysis based on the data of MODIS-NDVI, tempe-rature, precipitation, digital elevation model. The results showed that vegetation cover in Xilin Gol had been increased from 2000 to 2020, which generally included three phases, i.e., stable fluctuation, rapid growth, and steady growth. The mean NDVI showed a zonal increasing distribution from southwest to northeast, and had a strong correlation with elevation and population density in Xilin Gol region. The high values of NDVI were mainly in the east, with a significant increasing trend, and the low values were in the southwest, with a local degradation. The sensitivity of vegetation cover to climate change showed spatial and temporal variations. The spatial variation of vegetation was more sensitive to temperature and the interannual variation was sensitive to annual precipitation. In summary, vegetation cover improved overall in Xilin Gol, but there was degradation in some areas. We should formulate differentiated and precise vegetation restoration and ecological environmental protection policies.

[Develop the rural ecology in the New Era]. / 发展新时代的乡村生态学.

Rural ecology is a comprehensive field of study that takes the rural social-ecological-economic systems as the objective object and emphasizes spatial carrier governance. The development of rural ecology in the New Era embodies and implements comprehensively the core concepts of Xi Jinping Thought on Socialism with Chinese Cha-racteristics for a New Era, including harmonious coexistence between humans and nature, rural revitalization, green development, and the comprehensive construction of a socialist modernized nation. Under the goal of Chinese-style modernization, rural ecology exhibits characteristics distinct from the past, such as the integration of research objects, the intersectionality of basic theories, the computational feature of technical methods, and the orientation of exporting outcomes. To provide disciplinary support for modernization-oriented science to meet the new demands of country's rural development, effectively narrating the story of sustainable rural development in China and providing fundamental guarantees for the safety of rural systems, a number of issues such as paradigm innovation in research, improvement of data quality, and integration of comprehensive technologies, should be fully considered.

[Approach and evidence-based study of provincial-level eco-economic development planning]. / çœçº§å°ºåº¦ç”Ÿæ€ç»æµŽå‘å±•è§„åˆ’ç¼–åˆ¶æ–¹æ³•åŠå®žè¯ç ”ç©¶.

The development of ecological economy is one of the core elements of the ecological civilization system and an essential means to optimize the social-ecological systems. The key to developing ecological economy lies in preparing the development plan to realize concrete implementation. Given the objective and realistic demand for the development of ecological economy, it is critically needed to propose the approach of eco-economic planning and conduct empirical research. We sorted out the connotation of ecological economy, proposed the general idea of "object identification-resource evaluation-principal construction-target setting-task content-mechanism guarantee", and proposed three work modules, including "preliminary preparation, content design, review & approval", and finally built a technical system for the preparation of provincial-scale ecological economy planning. We outlined the 14th Five-Year Plan for Eco-Economic Development of Liaoning Province, and discussed critical issues such as the connotation definition and index system establishment for eco-economic development plan. This work provides ideas for the scientific and standardized preparation of ecological economy development plan at the provincial level in China.

[Nitrogen flow and polluted nitrogen footprint accounting of rural systems at the municipal scale: The case of Shenyang]. / å¸‚åŸŸå°ºåº¦å†œæ‘ç³»ç»Ÿæ°®ç´ æµåŠ¨åŠæ±¡æŸ“æ°®è¶³è¿¹æ ¸ç®—­­ä»¥æ²ˆé˜³å¸‚为例.

Understanding the process of nitrogen flow, emission, and utilization in rural systems is of great importance to reduce pollutant emissions caused by agricultural activities and to promote the sustainable utilization of nutrient resources. Based on the NUFER (nutrient flow in food chain, environment and resources use) model and nitrogen footprint approach, we proposed a nitrogen accounting framework for municipal-scale rural systems, and conducted a quantitative and time series-based comparative study on nitrogen flow, recycling, and footprint from the perspective of three subsystems, namely planting, animal husbandry, and rural human settlement in Shenyang from 1998 to 2018. The results showed that: 1) nitrogen utilization rates of the planting subsystem, animal husbandry subsystem, and rural human settlement subsystem were 36.1%, 59.7%, and 70.1%, respectively in 2018, with a growth rate of 15.9%, 9.1%, and 0.7% respectively compared to 1998; 2) The total polluted nitrogen footprint in Shenyang grew rapidly from 1998 to 2014, but declined from 2014 to 2018. In 2018, the total footprint of nitrogen pollution was 123.5 Gg, increasing by 21.6% compared with 1998; 3) In 2018, the unused nitrogen in the planting subsystem, animal husbandry subsystem, and rural human settlement subsystem were 129.5, 62.2, and 8.7 Gg, respectively, which were equivalent to 420.4, 202.1, and 8.7 Gg of nutrient resources from nitrogen fertilizer, respectively. In general, the nitrogen use efficiency of rural system increased gradually from the production end to the consumption end, but the temporal and spatial variation of nitrogen in rural systems need further studies.

[An emergy-ecological footprint model based evaluation of ecological security at the old industrial area in Northeast China: A case study of Liaoning Province.] / 基于能值-ç”Ÿæ€è¶³è¿¹æ¨¡åž‹çš„ä¸œåŒ—è€å·¥ä¸šåŸºåœ°ç”Ÿæ€å®‰å ¨è¯„ä»·­­ä»¥è¾½å®çœä¸ºä¾‹.

Based on the integrated model of emergy-ecological footprint approaches, the ecological security of Liaoning Province, a typical case for the old industrial area, was quantitatively evaluated from 2003 to 2012, followed by a scenario analysis on the development trend of the ecological secu-rity by employing the gray kinetic model. The results showed that, from 2003 to 2012, the value of emergy ecological-capacity per capita in Liaoning Province decreased from 3.13 hm2 to 3.07 hm2, while the emergy-ecological footprint increased from 13.88 hm2 to 21.96 hm2, which indicated that the ecological deficit existed in Liaoning Province and the situation was getting worse. The ecological pressure index increased from 4.43 to 7.16 during the studied period, and the alert level of ecological security changed from light to middle level. According to the development trend, the emergy ecological capacity per capita during 2013-2022 would correspondingly decrease from 3.04 hm2 to 2.98 hm2, while the emergy ecological footprint would increase from 22.72 hm2 to 35.87 hm2, the ecological pressure index would increase from 7.46 to 12.04, and the ecological deficit would keep increasing and the ecological security level would slide into slightly unsafe condition. The alert level of ecological security would turn to be middle or serious, suggesting the problems in ecological safety needed to be solved urgently.

[Driving forces of carbon emission from energy consumption in China old industrial cities: a case study of Shenyang City, Northeast China].

To quantitatively analyze the effects of anthropogenic factors on regional environmental quality is a hot topic in the field of sustainable development research. Taking the typical old industrial city Shenyang in Northeast China as a case, and by using the IPCC method for calculating carbon emission from energy consumption, this paper estimated the carbon emission from energy consumption in the city in 1978-2009, and a time series analysis on the anthropogenic factors driving this carbon emission was made by the STIRPAT model based upon Kaya equation and ridge regression. In 1978-2009, the carbon emission in the city had a slow increase first, slow decrease then, and a rapid increase thereafter. The total carbon emission in 2009 was 4.6 times of that in 1978. Population growth was the main factor driving the growth of the emission, and there existed an equal-proportional variation between the population growth and the carbon emission growth. Urbanization was another main driving factor followed by population growth, and the per capita GDP was positively correlated with the carbon emission. Kuznets curve did not exist for the relationship between economic development and carbon emission in Shenyang. Energy source intensity reduction (representing technology improvement) was the main factor driving the reduction of the total carbon emission.

[Analysis on barriers of urban sustainable development based on DEMATEL: a case of Shenyang City].

To scientifically identify the key barriers which the urban sustainable development is facing and to analyze the interrelationships among the barriers are of significance to promote urban sustainable development. Through literature review, site investigation and structural interview, 21 factors affecting the Shenyang City's sustainable development were recognized, and based on questionnaire survey and statistics analysis, 12 main factors were screened. Further, by employing decision-making and trial evaluation laboratory (DEMATEL) method, the interrelationships among these factors were analyzed. The key factors affecting the Shenyang's sustainable development included the lack of leaders' attention, the economy-oriented governmental performance evaluation system, the lower public awareness on sustainable development, and the lack of academic understanding on regional eco-carrying capacity and related key projects. It was suggested that the local government should pay more attention on sustainable development, increase propaganda activities, reform governmental performance evaluation system, establish a reward-punishment system for promoting sustainable development and an effective monitoring mechanism, and enhance the implementation of related regulations, the local enterprises should establish research and development funds to support the researches of key technologies and introduce key projects, and general publics should improve their awareness on sustainable development and actively participate in related activities.

Biological leaching of heavy metals from a contaminated soil by Aspergillus niger.

Bioleaching of heavy metals from a contaminated soil in an industrial area using metabolites, mainly weak organic acids, produced by a fungus Aspergillus niger was investigated. Batch experiments were performed to compare the leaching efficiencies of one-step and two-step processes and to determine the transformation of heavy metal chemical forms during the bioleaching process. After the one or two-step processes, the metal removals were compared using analysis of variance (ANOVA) and least-significance difference (LSD). A. niger exhibits a good potential in generating a variety of organic acids effective for metal solubilisation. Results showed that after the one-step process, maximum removals of 56%, 100%, 30% and 19% were achieved for copper, cadmium, lead and zinc, respectively. After the two-step process, highest removals of 97.5% Cu, 88.2% Cd, 26% Pb, and 14.5% Zn were obtained. Results of sequential extraction showed that organic acids produced by A. niger were effective in removing the exchangeable, carbonate, and Fe/Mn oxide fractions of Cu, Cd, Pb and Zn; and after both processes the metals remaining in the soil were mainly bound in stable fractions. Such a treatment procedure indicated that leaching of heavy metals from contaminated soil using A. niger has the potential for use in remediation of contaminated soils.

Effects of dissolved low molecular weight organic acids on oxidation of ferrous iron by Acidithiobacillus ferrooxidans.

A few researchers have reported on work concerning bioleaching of heavy-metal-contaminated soil using Acidithiobacillus ferrooxidans, since this acidophile is sensitive to dissolved low molecular weight (LMW) organic acids. Iron oxidation by A. ferrooxidans R2 as well as growth on ferrous iron was inhibited by a variety of dissolved LMW organic acids. Growth experiments with ferrous iron as an oxidant showed that the inhibition capability sequence was formic acid>acetic acid>propionic acid>oxalic acid>malic acid>citric acid. The concentrations that R2 might tolerate were formic acid 0.1mmolL(-1) (2mmolkg(-1)soil), acetic and propionic acids 0.4mmolL(-1) (8mmolkg(-1)soil), oxalic acid 2.0mmolL(-1) (40mmolkg(-1)soil), malic acid 20mmolL(-1) (400mmolkg(-1)soil), citric acid 40mmolL(-1) (800mmolkg(-1)soil), respectively. Although R2 was sensitive to organic acids, the concentrations of LMW organic acids in the contaminated soils were rather lower than the tolerable levels. Hence, it is feasible that R2 might be used for bioleaching of soils contaminated with metals or metals coupled with organic compounds because of the higher concentrations of LMW organic acids to which R2 is tolerant.

[Catalytic dechlorination of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl in soil by Pd/Fe].

Dechlorination of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl in soil was studied by using Pd/Fe bimetallic catalytic reduction. 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl can be dechlorinated effectively by Pd/Fe bimetal. It was found that the removal efficiency of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl in soil could reach 54% after 5 days of reaction with 1 g of Pd/Fe (Pd loading 0.05%) and at an initial pH of 5.6. Several important experiment parameters involved in this process were also studied, including Pd loading, initial soil pH, the reaction time, the amount of Pd/Fe used and 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl initial concentration. The results showed that higher Pd loading, higher dosage of Pd/Fe, lower initial concentration of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl and weak acid condition were beneficial to the catalytic dechlorination of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl. The degradation of 2, 2', 3, 4, 4', 5, 5'- heptachlorobiphenyl, catalyzed by Pd/Fe, followed first-order kinetics, and the rate constant was 0.014 2/h, the half life was 49 h. In addition, two possible mechanisms of the dechlorination reaction were proposed and discussed.

[Study on phytoremediation of phenanthrene-contaminated soil with alfalfa (Medicago sativa L.)].

Pot experiment was used to investigate phytoremediation of phenanthrene-contaminated soil with alfalfa (Medicago sativa L.). Results indicated that phenanthrene had inhibitive effect on alfalfa growth, and higher phenanthrene concentration seriously prevent alfalfa growth. When the concentration was 445.22 mg/kg, the shoot and root biomasses were only 57.31% and 31.20% of control respectively. Alfalfa significantly promoted phenanthrene degradation in the soil. After 60 days, 85.68%-91.40% and 75.25%-86.61% of spiked phenanthrene disappeared from the rhizosphere and non-rhizosphere soils respectively. And the average removal ratio of phenanthrene in rhizosphere soils was 6.33% higher than that in non-rhizoshpere soils. The residual concentration of phenanthrene in the rhizosphere was lower than that in the non-rhizosphere but the dehydrogenase activity was on the contrary. With phenanthrene concentration increase the removal ratio and dehydrogenase activity decreased. A positive correlation was observed between the soil dehydrogenase activity and the removal ratio of phenanthrene in both the rhizosphere and non-rhizosphere soils. Therefore the presence of alfalfa roots was effective in promoting the phytoremediation of phenanthrene.