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2019, 11 (3) Online: 30 June 2019 Previous issue
  • Studies on eco-environmental change in source regions of the Yangtze and Yellow Rivers of China:present and future
  • JianPing Yang
  • DOI: 10.3724/SP.J.1226.2019.00173.
  • 2019, Vol.11 (3): 173–183 Abstract ( 82) HTML ( 6) PDF (2405 KB) ( 39 )
  • The source regions of the Yangtze and Yellow Rivers are important in the field of eco-environmental change research in China because of its distinct alpine ecosystem and cryosphere environment. At present, there are three different concepts on the extent of source areas of the Yangtze and Yellow Rivers: hydrological, geographical, and eco-environmental. Over the past decades, annual average air temperature has warmed significantly; moreover, the temperature rise rate increases notably with increase of time of the data series. Annual precipitation has no obvious increase or decrease trend, and the climate has become warm and dry in the source regions. As a result, the cryosphere in the regions has shrunk significantly since 1960s. A warm and dry climate and changing cryosphere together induced a substantial declination of alpine wetlands, marked decrease in river runoff, significant degradation of alpine grassland, and a reduction of engineering stability. The ecological environment, however, has a tendency for restoration in the regions because the climate has become gradually warm and wet since 2000. Thus, studies on eco-environmental change is transforming from a single element to multidisciplinary integration. Climate change-cryopshere change-physical and socioeconomic impacts/risk-adaptation constitute a chain of multidisciplinary integration research.

  • Variation and relationship between soil moisture and environmental factors in the source region of the Yangtze River from 2005 to 2016
  • LingLing Song,ZongJie Li,Qing Tian,LieFu Wang,Jing He,RuiFeng Yuan,Juan Gui,BaiJuan Zhang,YueMin Lv
  • DOI: 10.3724/SP.J.1226.2019.00184.
  • 2019, Vol.11 (3): 184–193 Abstract ( 56) HTML ( 4) PDF (4518 KB) ( 24 )
  • This study analyzed soil moisture, soil erosion, and vegetation in the source region of the Yangtze River from 2005 to 2016. We found that soil moisture showed an increasing trend from 2005 to 2009 but decreased from 2009 to 2016. The surface soil moisture was severely affected by seasonal changes in the source region of the Yangtze River, especially in the soil from 0 to 40 cm. However, seasonal variation of soil moisture deeper than 40 cm was different from that in the upper layer. Soil moisture below 40 cm wasn't affected by the seasonal variation. Soil moisture from 0 to 50 cm and the average thickness of wind deposition showed a positive correlation in the study area from 2005 to 2016. For environmental protection in the source region of the Yangtze River, wind deposition played a role in water retention. Similarly, a positive correlation also existed between the average thickness of wind erosion and soil moisture. Deep-soil moisture was the key factor for vegetation structure on the Qinghai-Tibet Plateau. The results are also helpful for further understanding the variation of soil moisture on the Tibetan Plateau and providing a scientific basis for effectively protecting and controlling the ecological environment in the future.

  • Assessing the impacts of ecological-living-productive land changes on eco-environmental quality in Xining City on Qinghai-Tibet Plateau, China
  • ZiYi Gao,HaiFeng Zhang,XiaoNan Yang,ZhiYuan Song
  • DOI: 10.3724/SP.J.1226.2019.00194.
  • 2019, Vol.11 (3): 194–207 Abstract ( 58) HTML ( 3) PDF (5003 KB) ( 32 )
  • The Ecological-living-productive land (ELPL) classification system was proposed in an effort to steer China’s land pattern to an ecological-centered path, with the development model shifting from a single function into more integrated multi-function land use. The focus is coordinating the man-land contradictions and developing an intensive, efficient and sustainable land use policy in an increasingly tense relationship between humans and nature. Driven by socioeconomic change and rapid population growth, many cities are undergoing urban sprawl, which involves the consumption of cropland and ecological land and threatens the ecological balance. This paper aims to quantitatively analyze the critical effects of ELPL changes on eco-environmental quality according to land use classification based on leading function of ecology, living and production from 1990 to 2015 with a case study of Xining City. Also, four future land use scenarios were simulated for 2030 using the Future Land Use Simulation (FLUS) model that couples human and natural effects. Our results show a decrease in productive land (PL) and an increase in ecological land (EL) and living land (LL) in Xining City. Forestry ecological land (FEL) covered the top largest proportion; agriculture productive land (APL) showed the greatest reduction and urban and rural living land (U-RLL) presented a dramatic increase. The eco-environmental quality improved in 1990-2010, mainly affected by the conversion of APL to FEL and GEL. However, the encroachment of U-RLL into APL, other ecological land (OEL) and FEL was the main contributor to the decline in eco-environmental quality in 2010-2015 as well as the primary reason for the increase area of lower-quality. The Harmonious Development (HD)-Scenario, characterized by a rational allocation of LL and PL and a better eco-environment, would have implications for planning and monitoring future management of ELPL, and may represent a valuable reference for local policy-makers.

  • MODIS observed snow cover variations in the Aksu River Basin, Northwest China
  • Jing Li,ShiYin Liu,Qiao Liu
  • DOI: 10.3724/SP.J.1226.2019.00208.
  • 2019, Vol.11 (3): 208–217 Abstract ( 42) HTML ( 4) PDF (2915 KB) ( 23 )
  • A major proportion of discharge in the Aksu River is contributed from snow- and glacier-melt water. It is therefore essential to understand the cryospheric dynamics in this area for water resource management. The MODIS MOD10A2 remote-sensing database from March 2000 to December 2012 was selected to analyze snow cover changes. Snow cover varied significantly on a temporal and spatial scale for the basin. The difference of the maximum and minimum Snow Cover Fraction (SCF) in winter exceeded 70%. On average for annual cycle, the characteristic of SCF is that it reached the highest value of 53.2% in January and lowest value of 14.7% in July and the distributions of SCF along with elevation is an obvious difference between the range of 3,000 m below and 3,000 m above. The fluctuation of annual average snow cover is strong which shows that the spring snow cover was on the trend of increasing because of decreasing temperatures for the period of 2000-2012. However, temperature in April increased significantly which lead to more snowmelt and a decrease of snow cover. Thus, more attention is needed for flooding in this region due to strong melting of snow.

  • Glacier mapping based on Chinese high-resolution remote sensing GF-1 satellite and topographic data
  • LiLi Yan,Jian Wang
  • DOI: 10.3724/SP.J.1226.2019.00218.
  • 2019, Vol.11 (3): 218–225 Abstract ( 38) HTML ( 1) PDF (8415 KB) ( 22 )
  • The precise glacier boundary is a fundamental requirement for glacier inventory, the assessment of climate change and water management in remote mountain areas. However, some glaciers in mountain areas are covered by debris. The high spatial resolution images bring opportunities in mapping debris-covered glaciers. To discuss the capability of Chinese GaoFen-1 satellite lacking the short wave infrared band and thermal infrared band in mapping glaciers, this study distinguished supraglacial terrain from surrounding debris by combining GaoFen-1 (GF-1) wide-field-view (WFV) images, the ratio of the thermal infrared imagery and morphometric parameters (DEM and slope) with 30 m resolution. The overall accuracy of 90.94% indicated that this method was effective for mapping supraglacial terrain in mountain areas. Comparing this result with the combination of GF-1 WFV and low-resolution morphometric parameters shows that a high-quality DEM and the thermal infrared band enhanced the accuracy of glacier mapping especially debris-covered ice in steep terrain. The user's and producer's accuracies of glacier area were also improved from 89.67% and 85.95% to 92.83% and 90.34%, respectively. GF data is recommended for mapping heavily debris-covered glaciers and will be combined with SAR data for future studies.

  • Stem radial growth indicate the options of species, topography and stand management for artificial forests in the western Loess Plateau, China
  • ShengChun Xiao,XiaoMei Peng,QuanYan Tian,Gong Zhu
  • DOI: 10.3724/SP.J.1226.2019.00226.
  • 2019, Vol.11 (3): 226–238 Abstract ( 33) HTML ( 0) PDF (4802 KB) ( 18 )
  • An understanding of the differences in artificial forest between tree species, slope aspects, and management options in arid environments is fundamentally important for efficient management of these artificial systems; however, few studies have quantified the spatial and temporal differences in stem radial growth of trees in the arid western Loess Plateau of China. Using dendrochronology, we assessed the growth of three woody species (the native shrub Reaumuria soongorica, the exotic shrub Tamarix ramosissima and tree Platycladus orientalis) by measuring the annual stem radial increment. We also describe the long-term growth trends and responses to climatic factors on slopes with different aspects during periods with and without irrigation. We found that precipitation during the main growing season was significantly positively correlated with ring growth for all three species and both slope aspects. In addition, supplemental water (e.g., irrigation, rainwater harvesting) greatly relieved drought stress and promoted radial growth. Our results suggest that as the main afforestation species in the Loess Plateau used for soil and water conservation, P. orientalis is more suitable than T. ramosissima under rain-fed conditions. However, a landscape that combined a tree (P. orientalis) with a shrub (R. soongorica) and grassland appears likely to represent the best means of ecological restoration in the arid western Loess Plateau.

  • A landscape management analysis framework and its preliminary application in Ejina Oasis, Northwest China
  • YouHua Ran,Yan Zhao
  • DOI: 10.3724/SP.J.1226.2019.00239.
  • 2019, Vol.11 (3): 239–247 Abstract ( 38) HTML ( 1) PDF (7491 KB) ( 22 )
  • The implementation of integrated landscape management to support local and regional human well-being is crucial in arid regions, but its application to date is very limited. Although analytical frameworks have been established to maximize ecosystem services via trade-offs between different landscape configurations, consumption factors such as water resources are rarely and weakly considered in such frameworks. In this paper, an improved integrated landscape-management analysis framework, called the Consumption-integrated Landscape Management to Ecosystem Service (CLMES), is proposed. In this framework, consumption factors are integrated at the same level as ecosystem services. The improved analytical framework is then used to assess and optimize landscape design in the Ejina Oasis, an extremely arid region in western China. Three landscape conditions (past, current, and future) are evaluated, based on the CLMES. Our results indicate that the Heihe River water-allocation program effectively promoted ecosystem services in the Ejina Oasis from 2000 to 2011. However, the excessive expansion of cropland led to a slight decline in habitat quality. An optimized landscape configuration and policy suggestions are proposed, which may be beneficial to the improvement of total water-use efficiency, oasis stability, and resilience of the ecological-social system in the Ejina Oasis.

  • Risk prevention and control strategies for the severely affected areas of snow disaster in the Three Rivers Source Region (TRSR), China
  • ShiJin Wang,ShengYun Chen,YanQiang Wei
  • DOI: 10.3724/SP.J.1226.2019.00248.
  • 2019, Vol.11 (3): 248–252 Abstract ( 52) HTML ( 8) PDF (7057 KB) ( 14 )
  • Historically, frequent and heavy snow disaster (SD) has caused serious livestock death and casualties, resulting in a devastating impact on animal husbandry development in the Three Rivers Source Region (TRSR). From winter in 2018 to spring in 2019, the largest SD occurred in this area over the past 10 years, especially in core zones of the Lancang River Source Region. Field research results show that the main causes of the major SD include weak infrastructure (i.e., roads, communications, warm sheds, and insufficient forage reserve), low rate of domestic animals for sale before the SD, and low loss settlement rate. SD occurrence could furtherly reduce the ability of disaster prevention, mitigation and relief of disaster loss. In the future, heavily affected SD areas should improve the forecasting ability of snowfall incidents, strengthen infrastructure construction, implement grass and livestock balance strategies, optimize livestock structure, improve loss settlement rate, and develop a modern compound model of animal husbandry development model that combines breeding, slaughtering and deep processing of animal product.