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2018, 10 (3) Online: 01 June 2018 Previous issue Next issue
  • Tessellons, topography, and glaciations on the Qinghai-Tibet Plateau
  • Stuart A. Harris, HuiJun Jin, RuiXia He, SiZhong Yang
  • DOI: 10.3724/SP.J.1226.2018.00187
  • 2018, Vol.10 (3): 187–206 Abstract ( 47) HTML PDF (2644 KB) ( 27 )
  • The Qinghai-Tibet Plateau has developed into a vast fortress-like structure that has recently presented a barrier limiting the egress of moisture-bearing air masses. Lower sea levels also affected the climate. This paper examines their effects on the current evidence for the timing of past glaciations, and the development and evolution of permafrost. There are two theories regarding glaciation on the Qinghai-Tibet Plateau (QTP). Kuhle suggested that there was a major, unified ice-cap during the Last Glacial Maximum (LGM), whereas major Chinese glaciologists and others have not found or verified reliable evidence for this per se. There have been limited glaciations during the last 1.1 Ma B.P. but with increasing dominance of permafrost including both primary and secondary tessellons infilled with rock, sand or loess. The East Asia Monsoon was absent in this area during the main LGM, starting at >30 ka B.P. on the plateau, with sufficient precipitation reappearing about 19 ka B.P. to produce ice-wedges. A weak Megathermal event took place between 8.5 and 6.0 ka B.P., followed by Neoglacial events exhibiting peak cold at 5.3-4.7 ka, 3.1-1.5 ka, and the Little Ice Age (LIA) after 0.7 ka. Subsequently, mean annual air temperature has increased by 4℃.
  • Characteristics of total suspended particulates in the atmosphere of Yulong Snow Mountain, southwestern China
  • HeWen Niu, XiaoFei Shi, Gang Li, JunHua Yang, ShiJin Wang
  • DOI: 10.3724/SP.J.1226.2018.00207
  • 2018, Vol.10 (3): 207–218 Abstract ( 40) HTML PDF (2221 KB) ( 12 )
  • The measurement of black carbon (BC) and organic carbon (OC), dust in total suspended particulates (TSP) was carried out at Yulong Snow Mountain (Mt. Yulong) and Ganhaizi Basin, in the Mt. Yulong region, southwestern China. TSP samples were analyzed using a thermal/optical reflectance carbon analyzer. Results show that average BC and OC concentrations in TSP in the Mt. Yulong region were 1.61±1.15 μg/m3 and 2.96±1.59 μg/m3, respectively. Statistical results demonstrated that there were significant differences in mean BC and OC contents between Ganhaizi Basin and Mt. Yulong at the 0.05 level. Strong correlations between BC and OC indicate their common dominant emission sources and transport processes. Temporal variations of BC, OC, and optical attenuation (ATN) values were consistent with each other in carbonaceous aerosols. The ratios of OC/BC in monsoon season were significantly higher than in non-monsoon in aerosols from Ganhaizi, which is closely related to the formation of secondary organic carbon (SOC) and extensive motor vehicle emissions from tourism activities. The temporal variations of BC, OC and ATN in carbonaceous aerosols in Ganhaizi and Mt. Yulong were totally different, probably due to elevation difference and diverse tourism activity intensity between the two sites. Time-averaged aerosol optical depth (AOD) at the wavelength of 550 nm in Mt. Yulong was higher than that of the inland of the Tibetan Plateau (TP). Source apportionment indicated that intensive exhaust emissions from tourism vehicles were the main local sources of atmospheric pollutant in the Mt. Yulong region. Biomass-burning emissions released from South Asia could penetrate into the inland of the TP under the transport of summer monsoon. Further study is needed to assess light absorption and radiative forcing of carbonaceous aerosols, and modeling research in combination with long-term in-situ observations of light-absorbing particulates (LAPs) in the TP is also urgently needed in future work.
  • Spatial variations of Pb, As, and Cu in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica
  • XingXing Jiang, ShuGui Hou, YuanSheng Li, HongXi Pang, Rong Hua, Mayewski Paul, Sneed Sharon, ChunLei An, Handley Michael, Ke Liu, WangBin Zhang
  • DOI: 10.3724/SP.J.1226.2018.00219
  • 2018, Vol.10 (3): 219–231 Abstract ( 41) HTML PDF (1847 KB) ( 42 )
  • The spatial distributions of lead, arsenic, and copper (Pb, As, and Cu, respectively) in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica, are presented. The mean concentrations of Pb, As, and Cu are 1.04±1.56 pg/g, 0.39±0.08 pg/g, and 11.2±14.4 pg/g, respectively. It is estimated that anthropogenic contributions are dominant for Pb, As, and Cu. Spatially, Pb concentrations show an exponentially decreasing trend from the coast inland, while a moderate decreasing trend is observed for Cu concentrations in the coastal area (below 2,000 m above sea level (a.s.l.)). In the intermediate area (2,000-3,000 m a.s.l.), the concentrations and enrichment factors of all these elements show high variability due to the complicated characteristics of climate and environment. On the inland plateau (above 3,000 m a.s.l.), the high concentrations of As and Pb are induced by high deposition efficiency, the existence of polar stratospheric precipitation, and the different fraction deposition to East Antarctica. The extremely high concentrations with maximum values of 9.59 pg/g and 69.9 pg/g for Pb and Cu, respectively, are suggested to result mainly from local human activities at the station. Our results suggest that source, transport pathway, and deposition pattern, rather than distance from the coast or altitude, lead to the spatial distributions of Pb, As, and Cu; and it is further confirmed by spatial variations of the three metals deposited over the whole continent of Antarctica.
  • Multifractal process of runoff fluctuation of the Kaidu River in Xinjiang, China
  • ShuangQing Liu, ZuHan Liu, WeiGuo Wang, YuePing Lu, XiaoLiang Zhu, Bin Guo
  • DOI: 10.3724/SP.J.1226.2018.00232
  • 2018, Vol.10 (3): 232–239 Abstract ( 71) HTML PDF (1619 KB) ( 33 )
  • Based on the hydrological data in the headwater region of the Kaidu River during 1972-2011, the multifractal process of runoff fluctuation was analyzed. Results indicated that, in the past 40 years, the overall runoff of the Kaidu River in Xinjiang has shown significant multifractal behavior. Its singular curve lnχq(ε)-ln(ε) verified a favorable scale invariance over the entire time scale. τ(q)-q proved that evolution of the runoff time series presented multifractal characteristics. Moreover, the multifractal spectrum f(α)-α curve was hooklike leftward which indicated that, compared to relatively large runoff events. And Δf<0 indicated that these relatively small events took the leading role; B<0 explained the Kaidu River's daily-runoff ascending tendency presented during 1972-2011. Besides that, the multifractal behavior of the Kaidu River's runoff variability over four decades was also analyzed. Generally speaking, by decades, their four corresponding spectrum variations were not noticeable. These Δα values showed larger runoff events occupied the leading position with some local values falling. During the 1970s to the 1990s, Δf<0 illustrated the probability of the daily runoff at the lowest point is always larger than that of the highest during three continuous decades. At the beginning of the 21st century, for Δf>0 the trend presented was contrary from the 1970s to the 1990s. B values suggested an overall trend of increases during 1972-2011. Until the 21st century, the runoff with a slightly descending tendency on the whole explained these relatively large runoff events taking the leading role for the Kaidu River; but sometimes, some small events also played the dominant role.
  • Spatiotemporal change of carbon storage in the Loess Plateau of northern Shaanxi, based on the InVEST Model
  • ShaoYang Liu, NingKe Hu, Jin Zhang, ZhiChao Lv
  • DOI: 10.3724/SP.J.1226.2018.00240
  • 2018, Vol.10 (3): 240–250 Abstract ( 48) HTML PDF (3607 KB) ( 15 )
  • In recent years, land use and land cover have under gone tremendous change on the Loess Plateau, leading to temporal and spatial variation over many ecological factors, such as carbon storage. Based on four series of land-use data from remote-sensing imaging, spatiotemporal changes of land-use types and volume changes were analyzed. Combined with carbon-stock-assessment modules of the InVEST (integrated valuation ecosystem services and tradeoffs) model, the carbon-storage change was estimated and analyzed at the subcounty and subbasin scales. The results show that (1) cultivated land and grassland area decreased, while woodland and urban land area increased in northern Shaanxi; (2) the average carbon storage in Huangling County and the Beiluo River Basin is the largest, while that of Yuyang County and the Xinshui River Basin is the minimum, and that of Wuqi County showed the greatest growth; (3) carbon storage in the study area showed a definite decrease in 2000, but in general has increased from 1995 to 2010; (4) carbon-storage figures of subbasins and counties are all restricted by the natural status and land-use landscape of the whole study area. From the results, it can be seen that the effect of ecological policies is remarkable. This study has important implications for the rational planning of land use, adjustment of the ecosystem carbon cycle, and related policies.
  • Comprehensive benefits assessment of the ecological management model in Hobq Desert of China
  • Rui Wang, LiHua Zhou, Yong Chen
  • DOI: 10.3724/SP.J.1226.2018.00251
  • 2018, Vol.10 (3): 251–260 Abstract ( 75) HTML PDF (1391 KB) ( 20 )
  • The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well known as the "Hobq model". It is important to evaluate the comprehensive benefits of the "Hobq model", but this has not been addressed in previous studies. Thus, we established an index system to comprehensively evaluate the benefits of the "Hobq model", using an analytic hierarchy process method from 1988 to 2013. The results show the following:ecological benefits of the "Hobq model" had a positive trend, but with fluctuations during 2008 and 2009; economic benefits increased by 74% and the maximum value occurred in 2013; and social benefits increased steadily, but with fluctuations in 2010 and 2011. The social benefits were higher than ecological and economic benefits in the same period. Trends in overall benefits of the "Hobq model" were similar to changes in ecological benefits, which increased each year.
  • Characterization of landscape pattern based on land economic niche change: A case study in Ganzhou, Gansu Province, China
  • HuaLi Tong, PeiJi Shi, XueBin Zhang, ZaiYan Li
  • DOI: 10.3724/SP.J.1226.2018.00261
  • 2018, Vol.10 (3): 261–270 Abstract ( 32) HTML PDF (1614 KB) ( 50 )
  • Land use change has a profound impact on biodiversity and ecological processes, and is closely related to changes in landscape patterns. This paper introduces the theory and method of land economic niche into landscape ecology, which provides a new method for spatial characterization of urban and rural spatial landscape patterns. Based on this theory, this paper analyzes the landscape pattern of Ganzhou District by using Landsat images as data source in 1995, 2000, 2005, 2010 and 2015. We calculated the land economic niche by applying the niche potential theory. Combined with the theory of landscape ecology, we explored the effects of the land economic niche change on the landscape pattern at a county scale. The results show that economic niche of construction land, watershed and farmland increased during 1995-2015, and grassland declined significantly. The economic niche of farmland, construction land, watershed and grassland show a negative correlation with the number of patches (NP), fragmentation index (FN) and the fractal dimension index (FD), and had a positive correlation with the aggregation index (AI). There was no significant correlation between the forest land economic niche and landscape metrics. The change of land economic niche has a driving effect on the landscape pattern of the county, which can represent the economic development direction of Ganzhou District. The land economic niche is closely related to the landscape type which can directly obtain an economic benefit.
  • Cluster planting impact on cotton growth, yield and biomass accumulation in an arid region oasis
  • TingTing Xie, PeiXi Su, WenZhi Zhao, LiShan Shan
  • DOI: 10.3724/SP.J.1226.2018.00271
  • 2018, Vol.10 (3): 271–278 Abstract ( 24) HTML PDF (1484 KB) ( 10 )
  • The cluster planting pattern (3 plants per hole) for cotton (Gossypium hirsutum L.) may increase economic yield over those of the traditional planting pattern (1 plant per hole) in arid regions of China. This increase in yield depends on either increased biomass production or greater partitioning to fruit. This study was conducted to determine whether differences in biomass accumulation or partitioning to reproductive growth contributed to higher yield in the cluster planting pattern compared with the traditional one. Growth parameters, biomass accumulation, crop growth rate and partitioning between cluster planting pattern and traditional planting pattern was compared in northwest of China. The biomass production and partitioning in cluster planting plot was higher than in traditional planting one. Biomass accumulation was faster early in the clustered treatment, and it was also higher at harvest time. Total dry matter production per unit area was significantly higher than in the traditional planting. On a per plant basis, dry matter accumulation was faster and total biomass production was significantly higher in the cluster planting pattern. Numbers of sympodia and boll sizes were also larger, indicating that facilitation among plants was promoting crop yield. The increase in yield in the cluster planting treatment occurred through increased partitioning of dry matter to fruits than in the traditional planting pattern, resulting in more bolls and increased lint yield in arid regions.