Table of Content

    12 April 2016, Volume 7 Issue 2 Previous Issue    Next Issue
    Spatio-temporal Differences and Driving Forces of Air Quality in Chinese Cities
    WANG Dai, LIU Yi
    2016, 7 (2):  77-84.  doi: 10.5814/j.issn.1674-764x.2016.02.001
    Abstract ( 446 )   PDF (541KB) ( 230 )   Save

    Deterioration of city air quality is the serious problem in the process of rapid urbanization and economic development in China. Taking 74 cities that have implemented the new Ambient Air Quality Standards (GB3095- 2012) since 2013 as examples, using statistical and ArcGIS spatial analysis method, the multi-scale temporal and spatial variations characteristics and the impact of social and economic factors on urban air quality variations, are analyzed in this paper. The main research conclusions are as follows:(1) Air quality in Chinese cities shows very significant seasonal variations, with higher air quality in summer and autumn, and lower air quality in spring and winter; (2) Seen from a daily pollution perspective, air pollution is very serious and will tend to be more serious in the future; (3) Seen from an hourly variation perspective, urban air quality is time coupled with social production and urban living; (4) The overall spatial pattern of urban air quality is high in the east and north and low in the west and south, but with an obvious trend towards regional integration. (5) Cities in different regions have different factors that cause air quality variations. In general, urbanization level and energy consumption per GDP are the common factors.

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    Impact of Land Cover on Temperature and Moisture Sensitivity of Soil Organic Matter Mineralization in Subtropical Southeastern China
    YANG Hao, HE Nianpeng, LI Shenggong, YU Guirui, GAO Yang, WANG Ruomeng
    2016, 7 (2):  85-91.  doi: 10.5814/j.issn.1674-764x.2016.02.002
    Abstract ( 320 )   PDF (474KB) ( 78 )   Save

    Understanding the temperature and moisture sensitivity of soil organic matter (SOM) mineralization variations with changes in land cover is critical for assessing soil carbon (C) storage under global change scenarios. We determined the differences in the amount of SOM mineralization and the temperature and moisture sensitivity of soils collected from six land-cover types, including an orchard, a cropland, and four forests, in subtropical southeastern China. The responses of SOM mineralization to temperature (5, 10, 15, 20, and 25°C) and moisture (30%, 60%, and 90% of water-holding capacity [WHC]) were investigated by placing soil samples in incubators. Soil C mineralization rate and cumulative C mineralization were higher in orchard and cropland soils than in other forest soils. With increasing temperature, soil C mineralization rates and cumulative C mineralization increased with the rise of WHC. The temperature sensitivity of soil C mineralization was not affected by land-cover type and incubation moisture. All soil temperature treatments showed a similar response to moisture. Cropland soil was more responsive to soil moisture than other soils. Our findings indicate that cropland and orchard soils have a higher ability to emit CO2 than forest soils in subtropical southeastern China.

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    Responses of Grassland Net Primary Productivity to Environmental Variables in Northern China
    LIU Fang, ZHANG Hongqi, XU Erqi, KANG Lei
    2016, 7 (2):  92-100.  doi: 10.5814/j.issn.1674-764x.2016.02.003
    Abstract ( 266 )   PDF (3928KB) ( 281 )   Save

    Various environmental factors affect net primary productivity (NPP) of grassland ecosystem. Extensive reports on the effects of environmental variables on NPP can be found in literature. However, the agreement on the relative importance of various factors in shaping the spatial pattern of grassland NPP has not yet been reached. Here a grassland in situ NPP database comprising 602 samples in northern China for 1980-1999 was developed based on a literature review of published biomass and forage yield field measurements. Correlation analyses and dominance analysis were used to quantify the separate and combined effects of environmental variables (climate, topography and soil) on spatial variation in NPP separately. Grassland NPP ranged from 4.76 g C m-2a-1 to 975.94 g C m-2a-1, showing significant variations in space. NPP increased with annual precipitation and declined with annual mean temperature significantly. Specifically, precipitation had the greatest impact on deserts, followed by steppes and meadows. Grassland NPP decreased with increasing altitude because of water limitation, and positively correlated with slope, but weakly correlated with aspect. Soil quality showed positive effects on NPP. Annual precipitation was the dominant factor affecting the spatial variability of net primary productivity, followed by elevation.

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    Carbon Mineralization Associated with Soil Aggregates as Affected by Short-term Tillage
    GUO Linlin, NISHIMURA Taku, IMOTO Hiromi, SUN Zhigang
    2016, 7 (2):  101-106.  doi: 10.5814/j.issn.1674-764x.2016.02.004
    Abstract ( 270 )   PDF (458KB) ( 148 )   Save

    Tillage practice has received much attention due to its effects on greenhouse gas emissions from agricultural fields. The understanding of carbon mineralization associated with soil aggregates helps to explore the influence mechanisms of tillage practice on soil carbon dynamics. Total carbon and carbon mineralization rates associated with various sizes of soil aggregates under no-tillage and tillage treatments were studied with a volcanic ash soil. Total carbon content in microaggregates (<0.25 mm) was higher than that in macroaggregates (>0.25 mm) for both the no-tillage and tillage treatments, since microaggregates of the volcanic ash soil include more fine silts and clay particles absorbing more organic agents. The carbon mineralization rate and total carbon were highly correlated (R2 = 0.6552, P = 0.002) for both treatments, suggesting that soil aggregate size is an important factor to influence the carbon mineralization rate. The no-tillage system showed the advantage of improving soil structure for volcanic ash soil. A larger proportion of microaggregates with relatively high carbon mineralization might contribute to the greater carbon loss from tilled soils. Unlike aggregate size, short-term tillage showed no significant effects on carbon mineralization rates associated with aggregates in a specific size class.

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    Remote Sensing Classification of Marsh Wetland with Different Resolution Images
    LI Na, XIE Gaodi, ZHOU Demin, ZHANG Changshun, JIAO Cuicui
    2016, 7 (2):  107-114.  doi: 10.5814/j.issn.1674-764x.2016.02.005
    Abstract ( 321 )   PDF (4596KB) ( 97 )   Save

    Successful biological monitoring depends on judicious classification. An attempt has been made to provide an overview of important characteristics of marsh wetland. Classification was used to describe ecosystems and land cover patterns. Different spatial resolution images show different landscape characteristics. Several classification images were used to map and monitor wetland ecosystems of Honghe National Nature Reserve (HNNR) at a plant community scale. HNNR is a typical inland wetland and fresh water ecosystem in the North Temperate Zone. SPOT-5 10 m × 10 m, 20 m × 20 m, and 30 m × 30 m images and Landsat -5 Thematic Mapper (TM) images were used to classify based on maximum likelihood classification (MLC) algorithms. In order to validate the precision of the classifications, this study used aerial photography classification maps as training samples because of their high accuracy. The accuracy of the derived classes was assessed with the discrete multivariate technique called KAPPA accuracy. The results indicate: (1) training samples are important to classification results. (2) Image classification accuracy is always affected by areal fraction and aggregation degree as well as by diversities and patch shape. (3) The core zone area is protected better than buffer zone and experimental zone wetland. The experimental zone degrades fast because of irrational development by humans.

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    Will Contextual Factors and Providing the Maximum Price Information Affect People’s Actual Willingness-to-pay in BDM Auctions? Evidence from Three Asian Countries
    JIN Jianjun, FRANCISCO Jamil Paolo, SPOANN Vin, BUDDHAWONGSA Piyaluk, MA Hua
    2016, 7 (2):  115-121.  doi: 10.5814/j.issn.1674-764x.2016.02.006
    Abstract ( 315 )   PDF (403KB) ( 59 )   Save

    The purpose of this study was to measure the effect of maximum price information and contextual factors on people’s bidding behaviors in a controlled Becker-DeGroot-Marschak (BDM) experimental auctions. 354 respondents from three Asian countries (China, Cambodia and the Philippines) participated in this study. In each country, both households with piped water connection and households without piped water connection were investigated. The sample in each country was then randomly assigned to two groups: one group was provided with a maximum price of a water filter and the other group was not provided with the maximum price information. The results show that the treatment group with maximum price information had a higher actual willingness-to-pay than the control group without maximum price information, but they were not significantly different. Our results also indicate that contextual and socioeconomic factors did play a role in participants’ bid results for the water filter.

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    The Relationship between Carbon Dioxide Emission Intensity and Economic Growth in China: Cointegration, Linear and Nonlinear Granger Causality
    TU Xiongling
    2016, 7 (2):  122-129.  doi: 10.5814/j.issn.1674-764x.2016.02.007
    Abstract ( 345 )   PDF (377KB) ( 231 )   Save

    This study is to use cointegration, linear and non-linear Granger causality test to investigate the relationship between carbon dioxide (CO2) emissionand economic growth (GDP) in China for the period 1961-2010. Our analysis shows that CO2 emission and GDP are balanced in the long-run. The results suggest that there is evidence that economic development can improve environmental degradation in the long-run. Moreover, the result of linear and non-linear Granger causality test indicates a long-run unidirectional causality running from GDP to CO2 emissions. The study suggests that in the long run, economic growth may have an adverse effect on the CO2 emissions in China. Government should take into account the environment in their current policies, which may be of great importance for policy decision-makers to develop economic policies to preserve economic growth while curbing of carbon emissions.

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    Ecological Functions of PV Power Plants in the Desert and Gobi
    CHANG Zhaofeng, LIU Shizeng, ZHU Shujuan, HAN Fugui, ZHONG Shennian, DUAN Xiaofeng
    2016, 7 (2):  130-136.  doi: 10.5814/j.issn.1674-764x.2016.02.008
    Abstract ( 248 )   PDF (2396KB) ( 37 )   Save

    Photovoltaic (PV) power generation is an emerging energy industry that is developing rapidly. A number of PV power plants have been established in the desert and Gobi areas in northwest China in recent years. Is there any ecological significance to the establishment of PV power plants? If yes, what is it? This paper tries to find the answer by analyzing meteorological data from the Hexi Corridor as well as the observational data of light and vegetation in the Minqin desert area. The results show that the solar energy converted from 1 m2 of PV panels is equivalent to the solar energy that is utilized by 260.75 m2 of desert plants in the desert area. In China, there is vast area of desert and Gobi, with frequent dust storms and aeolian sand, as well as rich sunlight resources. Therefore, to develop the PV industry in the desert and Gobi regions will not only create considerable economic benefits, but will also be of great ecological significance. On the one hand, PV can effectively regulate thermodynamic equilibrium on the surface, helping to prevent sandstorms and reduce aeolian sand. The development of the PV industry is a win-win that generates economic returns and provides ecological protection by combating desertification. On the other hand, the PV industry can be developed without taking up arable land or other types of land. There are frequently high winds in the desert and Gobi region. PV power plants, together with wind power generation, are useful to transform and consume the power source that creates duststorms and aeolian sandflow in the desert and Gobi areas. This results in fewer sandstorms and reduced aeolian sandflow.

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    The Failure of Cooperative Farming Development Policies in Tōhoku, Japan
    MIYAKE Yoshitaka
    2016, 7 (2):  137-143.  doi: 10.5814/j.issn.1674-764x.2016.02.009
    Abstract ( 272 )   PDF (424KB) ( 55 )   Save

    In the context of agricultural globalization, many national governments have instituted policies, such as cooperative farming, to help farmers improve their profitability, competitiveness, and the sustainability of their agricultural practices. This study focused on the Multi-Product Management Stabilization Plan developed in Japan in 2006, which aimed to adapt the agricultural practices in the country to globalization by focusing on cooperative farming, and assessed its effectiveness for developing and incorporating cooperative farming in the Tōhoku region in the 2000s. The results suggest that regional and prefectural agents experienced significant difficulties when attempting to develop cooperative farming. Although New Institutional Economics’ theories suggest that these policies reflect the norms for developing agriculture more profitably and competitively, Japanese farmers did not regard the policies as relevant, practical, or sustainable, and they obstructed them.

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    A Checklist of Macrofungi in Yaoluoping Nature Reserve, Anhui
    HE Yanxin, WU Wangbao, LI Nengshu
    2016, 7 (2):  144-150.  doi: 10.5814/j.issn.1674-764x.2016.02.010
    Abstract ( 253 )   PDF (1504KB) ( 67 )   Save

    Field work to survey and investigate the Anhui Yaoluoping Macrofungi Nature Reserve was undertaken in order to understand and rationally develop macrofungi resources. The results showed that there are, in total, 101 macro-fungal species and varieties, including 59 kinds of edible mushroom, 20 kinds of medicinal mushroom, and 8 kinds of toadstools, grouped according to their economic values. The species belong to 5 classes, 13 orders, 43 families and 67 genera, Another 14 species are unknown fungus food or medicine and remains to be further developed. They are widely distributed in broad-leaved forests, mixed forests, coniferous forests, bamboo forests, wastelands and areas with other vegetation types. Large fungi resources are abundant; some varieties are rare and very valuable to develop. Among those of value are some edible and medicinal mushrooms, anti-cancer sulfur bacteria, morchella, gold equivalent cow bacilli, pine mushrooms, etc. Some species and species resources have still not been fully investigated. These large fungi can be domesticated and cultivated, and have very good commercial development prospects.

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