Effect of Aspect on Climate Variation in Mountain Ranges of Shennongjia Massif,Central China

The aim of this study was to better understand the mechanisms of regional climate variation in mountain ranges with contrasting aspects as mediated by changes in global climate. It may help predict trends of vegetation variations in native ecosystems in natural reserves. As measures of climate response, temperature and precipitation data from the north, east, and south-facing mountain ranges of Shennongjia Massif in the coldest and hottest months(January and July), different seasons(spring, summer, autumn, and winter) and each year were analyzed from a long-term dataset(1960 to 2003) to tested variations characteristics, temporal and spatial quantitative relationships of climates. The results showed that the average seasonal temperatures and precipitation in the north, east, and south aspects of the mountain ranges changed at different rates. The average seasonal temperatures change rate ranges in the north, east, and south-facing mountain ranges were from –0.0210℃/yr to 0.0143℃/yr, –0.0166℃/yr to 0.0311℃/yr, and –0.0290 ℃/yr to 0.0084℃/yr, respectively, and seasonal precipitation variation magnitude were from –1.4940 mm/yr to 0.6217 mm/yr, –1.6833 mm/yr to 2.6182 mm/yr, and –0.8567 mm/yr to 1.4077 mm/yr, respectively. The climates variation trend among the three mountain ranges were different in magnitude and direction, showing a complicated change of the climates in mountain ranges and some inconsistency with general trends in global climate change. The climate variations were significantly different and positively correlated cross mountain ranges, revealing that aspects significantly affected on climate variations and these variations resulted from a larger air circulation system, which were sensitive to global climate change. We conclude that location and terrain of aspect are the main factors affecting differences in climate variation among the mountain ranges with contrasting aspects.     

浙江省天目山地区土壤地质与地球化学特征

阐述了浙江省天目山地区的土壤地质、地球化学特征和农用灌溉水环境,对不同地质背景区土壤元素的本底值、养分水平、主要微量元素平均含量和土壤环境质量情况进行了对比评价.结果表明,该区土地环境质量达Ⅰ级标准,水环境质量达Ⅱ类标准,是浙北地区发展特色农业、生态农业、生态旅游业和开发绿色食品、有机食品等绿色产业区带的理想区块之一.     

Effective seed distribution pattern of an upward shift species in alpine tundra of Changbai Mountains

The vegetation of alpine tundra in the Changbai Mountains has experienced great changes in recent decades. Narrowleaf small reed(Deyeuxia angustifolia), a perennial herb from the birch forest zone had crossed the tree line and invaded into the alpine tundra zone. To reveal the driven mechanism of D. angustifolia invasion, there is an urgent need to figure out the effective seed distribution pattern, which could tell us where the potential risk regions are and help us to interpret the invasion process. In this study, we focus on the locations of the seeds in the soil layer and mean to characterize the effective seed distribution pattern of D. angustifolia. The relationship between the environmental variables and the effective seed distribution pattern was also assessed by redundancy analysis. Results showed that seeds of D. angustifolia spread in the alpine tundra with a considerable number(mean value of 322 per m2). They were mainly distributed in the low elevation areas with no significant differences in different slope positions. Effective seed number(ESN) occurrences of D. angustifolia were different in various plant communities. Plant communities with lower canopy cover tended to have more seeds of D. angustifolia. Our research indicated reliable quantitative information on the extent to which habitats are susceptible to invasion.     

Topographic controls on alpine treeline patterns on Changbai Mountain,China

The control mechanisms of topography on alpine treeline pattern are critical to understanding treeline dynamics and future changes. These mechanisms have not been understood quite well enough because of increasing human disturbance and low data resolution. In this study, the relationship between the treeline pattern and topography was analyzed based on high spatial resolution remote sensing data and a digital elevation model in an area in Changbai Mountain with little human disturbance. Future treeline patterns were also predicted. The results showed that(a) aspects with high solar radiation and low snow cover have a high coverage rate of trees,(b) the peak coverage rate of trees switches from low slopes(5°) to medium slopes(5°~25°) as the elevation rises because of the extreme environment,(c) the coverage rate of trees is a function that depends on environmental factors controlled by topography,(d) the future treeline pattern is controlled by new temperature mechanisms, new environmental factors and the reallocation effect of topography. Our research implies that topography controls the treeline pattern and changes in the treeline pattern associated with global warming, due to the effect of global warming on environmental factors. This study may well explain the causes of heterogeneous changes in the treeline pattern in the horizontal direction as well as differences in treeline response to climate warming.     

Climate Change Impacts on Agroecosystems in China: Processes,Mechanisms and Prospects

Building a more resilient response system to climate change for sustainable development and reducing uncertainty in China’s food markets, requires access to historical research gaps and mapping future research progress for decision making. However, the lack of quantitative and objective analyses to ensure the stability and development of agroecosystems increases the complexity of agro-climatic mechanisms, which leads to uncertainty and undesirable consequences. In this paper, we review the chara...     

Climate-growth relationship stability of Picea crassifolia on an elevation gradient,Qilian Mountain,Northwest China

Climate affects Picea crassifolia growth and climate change will lead to changes in the climate–growth relationship(i.e., the "divergence" phenomenon). However, standardization methods can also change the understanding of such a relationship. We tested the stability of this relationship by considering several variables: 1) two periods(1952–1980 and 1981–2009), 2) three elevations(2700, 3000, and 3300 m), and 3) chronologies detrended using cubic splines with two different flexibilities. With increasing elevation, the climatic factor limiting the radial growth of Picea crassifolia shifted from precipitation to temperature. At the elevation of 2700 m, the relationship between radial growth and mean temperature of the previous December changed so that the more flexible spline had a greater precipitation signal. At the elevation of 3000 m, positive correlation of radial growth with mean temperature and precipitation in September of the previous year became more significant. At the elevation of 3300 m, positive correlation between radial growth and precipitation of the currentsummer and the previous spring and autumn was no longer significant, whereas the positive correlation between radial growth and temperature of the current spring and summer strengthened. The detrending with the most flexible spline enhanced the precipitation signal at 2700 m, while that with the least flexible spline enhanced the temperature signal at 3300 m. All results indicated that the divergence phenomenon was affected by the climatic signals in the chronologies and that it was most dependent on the detrending method. This suggests it is necessary to select a suitable spline bootstrap for studies of growth divergence phenomena.     

Analysis of Tianchi volcano activity in Changbai Mountain,NE China

Changbaishan volcano is the largest potential eruptive volcano in China.In this paper,seismic activity,horizontal displacement,vertical displacement and the fluid geochemistry data acquiring from Changbaishan Tianchi Volcano Observatory(TVO) in recent years are analyzed.The authors discussed the ability for the Changbaishan volcanic seismic monitoring and active level of Changbaishan volcano in recent years based on the fundamental monitoring results.The results show that Changbaishan volcano has experience...     

Detecting and attributing vegetation changes in Taihang Mountain,China

Attributing vegetation changes provide fundamental information for ecosystem management,especially in mountainous areas which has vulnerable ecosystems. Based on the Normalized Difference Vegetation Index(NDVI) data, the spatial-temporal change of vegetation was detected in Taihang Mountain(THM) from 2000 to 2014. The topographical factors were introduced to interpret the response of vegetation variation to climate change and human activities. Results showed that the avegaged NDVI during growing season showed a single-peak curve distribution, with the largest value(0.628) among 1600-1800 m. A significant greening trend was detected in THM, with the largest increasing rate(0.0078 yr~(-1)) among the elevation of1600-1800 m and slope gradient between 3~5°. The partial correlation and multiple correlation analyses indicated that vegetation variation in more than81.8% pixels of the THM was mainly impacted by human activities. In the low elevation zones less than1000 m, increasing precipitation is the principle factor promoting vegetation restoration, whereas in the high elevation zones of THM, temperature is the restricted factors impacting vegetation variation.Considering the dramatic climate change in the future,further studies should be conducted to explore inherent mechanism of vegetation growth to dynamic environment changes.     

Analysis of Tianchi volcano activity in Changbai Mountain，NE China

Changbaishan volcano is the largest potential eruptive volcano in China.In this paper,seismic activity,horizontal displacement,vertical displacement and the fluid geochemistry data acquiring from Changbaishan Tianchi Volcano Observatory(TVO) in recent years are analyzed.The authors discussed the ability for the Changbaishan volcanic seismic monitoring and active level of Changbaishan volcano in recent years based on the fundamental monitoring results.The results show that Changbaishan volcano has experienced an unrest episode from 2002 to 2005,but its active level recovers to the background now.     

COMPARISON OF QUATERNARY DEPOSIT ENVIRONMENT AMONG LUSHAN,HUANGSHAN AND TIANMU MOUNTAINS

TheQuaternalypaleo--environmentoftheLushan,HuangshanandTianmumountainsisasignificantacademicproblemtowhichmuchattentionhasbeenpaidbymanyresearchersingeosciencecircle.Manyscholarshavestudiedtheproblemandgotalotofachivementsoverthepastyears(Lee,1933;Lee,1936;Lee,1947;Ren,1953;Huang,1963;Li,1974;Shi,1989).HOWever,identicalviewsandconclusionshavenotbeenreachedyetuptillnow,especiallylackingofcomprehensivestudyforsedimentsintheseregions.Inrecentyears,applyingsedimentalcomprehensiveindexgotfromv…     

Climate change and its effects on runoff of Kaidu River,Xinjiang, China: A multiple time-scale analysis

This paper applied an integrated method combining grey relation analysis, wavelet analysis and statistical analysis to study climate change and its effects on runoff of the Kaidu River at multi-time scales. Maj or findings are as follows： 1） Climatic factors were ranked in the order of importance to annual runoff as average annual temperature, average temperature in autumn, average temperature in winter, annual precipitation, precipitation in flood season, av- erage temperature in summer, and average temperature in spring. The average annual temperature and annual precipitation were selected as the two representative factors that impact the annual runoff. 2） From the 32-year time scale, the annual runoff and the average annual temperature presented a significantly rising trend, whereas the annual precipitation showed little increase over the period of 1957-2002. By changing the time scale from 32-year to 4-year, we observed nonlinear trends with increasingly obvious oscillations for annual runoff, average annual temperature, and annual precipitation. 3） The changes of the runoff and the regional climate are closely related, indicating that the runoff change is the result of the regional climate changes. With time scales ranging from 32-year, 16-year, 8-year and to 4-year, there are highly significant linear correlations between the annual runoff and the average annual temperature and the annual precipitation.     

太行山山前平原地下水补给规律分析:以河北栾城为例

采用水均衡法与通量法对太行山山前平原(河北栾城)进行了地下水补给评价,结果表明:近20a地下水入渗补给量为
8~172mm/a(水均衡法),平均值49.3mm/a,变化幅度大。其中2004年入渗补给量(63mm/a)比采用通量法计算结果(28.2
mm/a)大一倍,表明土壤优先流对入渗补给作用显著。年入渗补给量总体上随有效降雨量增加、地下水位下降速率减少、作物实
际蒸发蒸腾量减少而增加,但与有效灌溉量和灌溉量之和的相关性不显著。通过长序列地下水位与灌溉量等数据估算得到研究
区侧向净补给量为125.2mm/a,约占地下水总补给量的71.7%(175.4mm/a),说明地下水主要以侧向补给为主。同时计算了入
渗补给与侧向补给地下水的延迟时间,分别为60a和1个月。      

Segmentation by domestic visitor motivation: Changbai Mountain Biosphere Reserve,China

Protected areas have become important tourism products that promoted as attractions by the tourism industry. Taking the Changbai Mountain Biosphere Reserve in Northeast China as a case, this study addresses visitor needs as a basis for developing a tourism strategy aimed at enhancing tourist opportunities at this reserve. A factor-cluster approach was employed to identify visitor segment profiles based on their visit motivations. Through random sampling, a pencil-and-paper questionnaire in Chinese language was collected from 637 domestic tourists in the study area. A principal components analysis of motivations revealed eight motivational factors, and four distinct groups of tourists – Nature travelers, Cultural landscape tourists, Food shopping enthusiasts, and Eclectic adventurers – were identified. Understanding the differences in these visitor segments will help the management authority effectively analyze nature reserve attributes and provide alternative activities and services to tourists. Finally, within the dual framework of market segmentation and destination management some management recommendations and marketing implications are suggested.     

Effect of Climate Variability and Human Activities on Runoff in the Jinghe River Basin,Northwest China

Much attention has recently been focused on the effects of climate variability and human activities on the runoff. In this study, we analyzed 56-yr(1957–2012) runoff change and patterns in the Jinghe River Basin(JRB) in the arid region of northwest China. The nonparametric Mann–Kendall test and the precipitation-runoff double cumulative curve(PRDCC) were used to identify change trend and abrupt change points in the annual runoff. It was found that the runoff in the JRB has periodically fluctuated in the past 56 yr. Abrupt change point in annual runoff was identified in the JRB, which occurred in the years around 1964 and 1996 dividing the long-term hydrologic series into a natural period(1957 – 1964) and a climate and man-induced period(1965 – 1996 and 1997 – 2012). In the 1965 – 1996 period, human activities were the main factor that decreased runoff with contribution of 88.9%, while climate variability only accounted for 11.1%. However,the impact of climate variability has been increased from 11.1% to 47.5% during 1997 – 2012, showing that runoff in JRB is more sensitive to climate variability during global warming. This study distinguishes theeffect of climate variability from human activities on runoff, which can do duty for a reference for regional water resources assessment and management.     

Middle and Late Permian palynoflora in Tianshan Township,southeast of Bogda Mountain,Xinjiang, China

The Permian is one of the most important periods during which the vegetative earth witnessed the transition from icehouse to greenhouse climate and the global environment changes. Organisms on the planet en-countered great challenge and the demise of swamp caused the extinction of arborescent lycopods and the rising of Mesophytic plants accomplished the floral transition from the Paleophytic to Mesophytic vegetation. In order to depict the climatic changes and floral succession in the middle and high latitudes of the North Hemisphere, palynological investigation was engaged, and 40 samples collected from the uppermost of Taerlang Formation, Hongyanchi Formation and Quanzijie Formation in the Tianshan Town, Turpan-Hami Basin, eastern Xinjiang, China. The result shows that the palynoflora in the studied area is composed of 50 species of 33 genera, domi-nated by disaccites and striatiti gymnosperm pollen, and characterized by diverse Protohaploxypinus, Hamia-pollenites, Alisporites and Klausipollenites. It is quite similar to those Middle and Late Permian palynological as-semblages reported in the Dalongkou section and other localities in southern margin of Junggar Basin, and aged at Middle and Late Permian. The diversity of typical Angara and sub-Angara pollen, such as Falcisporites, Alisporites, Protohaploxypinus, Vittatina, Lunatisporites, Hamiapollenites, etc. indicates that the studied palyno-flora belonged to the sub-Angara phytoprovince, while the presence of Lueckisporites virkkiae implied Euramerica pollen intruded northward sometimes. The paleoclimate of the studied area might be warm and humid with fluc-tuated dry seasons during the late Guadalupian and early Lopingian time.     

中国历史山洪灾害分布特征研究

中国山洪灾害发生频繁,区域分布差异性明显且难以预报,关于山洪灾害分布特征的研究对于山洪灾害预警、山洪灾害防治区规划等具有重要意义。本文以历史山洪灾害点为基础数据,以6个一级地貌大区（东部平原低山丘陵大区（Ⅰ）、东南低山丘陵平原大区（Ⅱ）、华北-内蒙东中山高原大区（Ⅲ）、西北高中山盆地高原大区（Ⅳ）、西南中低山高原盆地大区（Ⅴ）、青藏高原高山极高山盆地谷地大区（Ⅵ））为基本分析单元,统计对比不同地貌区域内山洪灾害数目、密度,并进一步分析山洪灾害随高程、高程标准差以及50年一遇6 h雨量（H6-50）的分布情况,从而获得中国历史山洪灾害的主要分布特征。结果表明：山洪灾害集中分布于东南低山丘陵平原大区及西南中低山高原盆地大区,占全国山洪灾害的60%左右。6 h雨量（H6-50）处于240~280 mm区域山洪灾害密度最大。高程标准差小于30 m区域山洪灾害密度较大。东南低山丘陵平原大区高程处于10~50 m间,高程标准差小于30 m,雨量（H6-50）在150~270 mm间地区山洪灾害密度较大;西南中低山高原盆地大区山洪灾害集中分布于高程600 m以下,高程标准差小于50 m,雨量（H6-50）大于120 mm地区。以地貌区划结果为基本分析单元相对于行政界线而言更有助于分析山洪灾害分布特征。     

中国耕地变化区的气候背景对比分析

研究我国耕地变化区的气候背景,对于了解耕地资源的生产能力,评价耕地占补平衡政策的实施效果,实现耕地资源保护和粮食安全等具有重要意义。本文在分析全国耕地空间变化的基础上,从年平均气温、年降水量和日照时数三个方面,研究耕地增加区和减少区的气候背景,并将其进行比较和分析,以期为国家保护耕地资源和发展农业生产等提供建议。研究结果表明,20世纪80年代末至2008年4个时段,耕地减少区比耕地增加区的年平均气温高0.45~1.05℃,年降水量高56.77~79.59mm,年日照时数少45.80~98.83h。耕地显著减少区比耕地显著增加区的年平均气温高0.81~1.85℃,年降水量高85.69~305.26mm,年日照时数少86.96~207.85h。在四个时段中,我国耕地重心逐渐北移且海拔升高。若海拔高度不变,耕地增加区比耕地减少区北移0.5-1个纬度,耕地显著增加区比耕地显著减少区北移1-2个纬度;若纬度不变,耕地增加区比耕地减少区,海拔升高100~200m,耕地显著增加区比耕地显著减少区,海拔升高150~350m。随年份增加,耕地增加区和显著增加区与耕地减少区和显著减少区在水分条件上的差别越来越大。这些结论对于研究我国粮食生产能力、评价耕地占补平衡、调整产业布局等具有重要意义。     

Character and Causes of Population Distribution in Shenyang City, China

1 Introduction Research on the character of urban population distribu- tion is one of the focuses of western urban geography. From the 1950s, the research has attracted the attention of many western researchers, and a series of classical theoretical models were put forward. For example, Clark (1951) found that with the increase of distance from the city center, the urban population density tends to de- crease in exponential. Through the statistical analysis of more than 20 cities, he put forw…     

Spatiotemporal Evolution Characteristics of Urban Land Surface Temperature Based on Local Climate Zones in Xi'an Metropolitan,China

Local climate zones(LCZs) are an effective nexus linking internal urban structures to the local climate and have been widely used to study urban thermal environment. However, few studies considered how much the temperature changed due to LCZs transformation and their synergy. This paper quantified the change of urban land surface temperature(LST) in LCZs transformation process by combining the land use transfer matrix with zonal statistics method during 2000–2019 in the Xi’an metropolitan. The r...