Areas Of Northeastern China Research Articles

Variability and climate change trend in vegetation phenology of recent decades in the Greater Khingan Mountain area, Northeastern China

Vegetation phenology has been used in studies as an indicator of an ecosystem’s responses to climate change. Satellite remote sensing techniques can capture changes in vegetation greenness, which can be used to estimate vegetation phenology. In this study, a long-term vegetation phenology study of the Greater Khingan Mountain area in Northeastern China was performed by using the Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index version 3 (NDVI3g) dataset from the years 1982–2012. After reconstructing the NDVI time series, the start date of the growing season (SOS), the end date of the growing season (EOS) and the length of the growing season (LOS) were extracted using a dynamic threshold method. The response of the variation in phenology with climatic factors was also analyzed. The results showed that the phenology in the study area changed significantly in the three decades between 1982 and 2012, including a 12.1-day increase in the entire region’s average LOS, a 3.3-day advance in the SOS and an 8.8-day delay in the EOS. However, differences existed between the steppe, forest and agricultural regions, with the LOSs of the steppe region, forest region and agricultural region increasing by 4.40 days, 10.42 days and 1.71 days, respectively, and a later EOS seemed to more strongly affect the extension of the growing season. Additionally, temperature and precipitation were closely correlated with the phenology variations. This study provides a useful understanding of the recent change in phenology and its variability in this high-latitude study area, and this study also details the responses of several ecosystems to climate change.

Size distributions and health risks of particulate trace elements in rural areas in northeastern China

To characterize the airborne trace elements (Be, Na, Mg, Al, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Se, Mo, Ag, Cd, Ba, Tl, Pb, Th and U) in rural areas in northeastern China, size-resolved aerosols were collected bi-weekly from March 2013 to February 2014 at two farmland sites in Shenyang (SHY) and Hailun (HLZ), a grassland site in Tongyu (TYU) and a forest site in the Changbai Mountain (CBS). The results showed that most trace elements (TEs) exhibited significantly higher concentrations at SHY than those at HLZ, TYU and CBS. All of the sites exhibited higher values in spring/winter than those in summer/autumn. Industrial imprints on the concentrations and size distributions of Pb and Cd were found at SHY, as supported by an air-mass backward-trajectory analysis and the abundance of sulfate and heavy metals. Due to the frequent influence of sand dust, the size distributions of Ca and Ba at the grassland site near Inner Mongolia had dominant peaks at 5.8–9μm, in contrast to the other agricultural and forest sites, which peaked at 4.7–5.8μm. In addition, the concentrations and the enrichment factors (EFs) of the TEs in this study increased as the size range decreased from coarse to fine particles, resulting in the highest carcinogenic (e.g., Pb) and non-carcinogenic (e.g., Mn) risks at 1.1–2.1μm. Overall, the results highlight the severe pollution of heavy metals in northeastern China, particularly in agricultural regions that are subject to anthropogenic influences. Mitigating atmospheric TEs in the studied region, an important commodity grain base in China, is urgently needed to protect the environment and human health from toxic metals.

Residence times of groundwater and nitrate transport in coastal aquifer systems: Daweijia area, northeastern China

Groundwater within the coastal aquifer systems of the Daweijia area in northeastern China is characterized by a large of variations (33–521mg/L) in NO3− concentrations. Elevated nitrate concentrations, in addition to seawater intrusion in the Daweijia well field, both attributable to anthropogenic activities, may impact future water-management practices. Chemical and stable isotopic (δ18O, δ2H) analysis, 3H and CFCs methods were applied to provide a better understanding of the relationship between the distribution of groundwater mean residence time (MRT) and nitrate transport, and to identify sources of nitrate concentrations in the complex coastal aquifer systems. There is a relatively narrow range of isotopic composition (ranging from −8.5 to −7.0‰) in most groundwater. Generally higher tritium contents observed in the wet season relative to the dry season may result from rapid groundwater circulation in response to the rainfall through the preferential flow paths. In the well field, the relatively increased nitrate concentrations of groundwater, accompanied by the higher tritium contents in the wet season, indicate the nitrate pollution can be attributed to domestic wastes. The binary exponential and piston-flow mixing model (BEP) yielded feasible age distributions based on the conceptual model. The good inverse relationship between groundwater MRTs (92–467years) and the NO3− concentrations in the shallow Quaternary aquifers indicates that elevated nitrate concentrations are attributable to more recent recharge for shallow groundwater. However, there is no significant relationship between the MRTs (8–411years) and the NO3− concentrations existing in the carbonate aquifer system, due to the complex hydrogeological conditions, groundwater age distributions and the range of contaminant source areas. Nitrate in the groundwater system without denitrification effects could accumulate and be transported for tens of years, through the complex carbonate aquifer matrix and the successive inputs of nitrogen from various sources.

Abstract 30: Are Man-made Pollutants Originating From China, Central Asia One Of The Windborne Mystery Infections Of Kawasaki Disease Carried Across The Pacific?

Kawasaki disease (KD) is an acute febrile illness predominately affecting children (75-80%) that is classified as an autoimmune vasculitis of small- to medium-sized arteries. KD is generally self-limited, although serious cardiac lesions develop in 25-30% of cases. Despite over four decades of extensive international investigation, no cause of KD has been confirmed. Significantly higher rates of concurrent viral infections were recently observed in patients during acute KD, while another study found significantly greater risk of early hospitalization for bacterial infections before KD onset. Several recent large investigations appear to confirm that patients are significantly more likely to develop asthma or common allergies such as acute rhinitis and atopic dermatitis both before and after KD. Seasonal shifts in large-scale wind currents originating from heavily polluted regions in China and Central Asia are significantly associated with the occurrence of KD cases in Japan, Hawaii, and San Diego. Recently, it appears these authors discovered that marked candida pollution from the soil of heavy agricultural and industrial areas in Northeastern China is significantly associated with the occurrence of KD in Japan. There is extensive precedent for trans-ocean wind transport of industrial pollutants, including across the Pacific. China now accounts for more than 50% of the world’s total anthropogenic emissions and is responsible for 20-29% of total air pollution in the United States, particularly as a result of its rapid industrialization and heavy reliance upon coal-fired power plants. Significantly higher consumption of seafood contaminated with methylmercury, PCBs, and dioxins may account for the disproportionate rates of KD in East Asian populations. In Japan, the appearance of KD during the 1950s and 1960s coincides with outbreaks of Minamata disease during this same period, which resulted from an unprecedented increase in mercury pollution and the contamination of seafood. Lastly, industrialization and subsequent pre- and postnatal exposure to various irritants are significantly associated with the development of asthma and common allergies during early childhood, which suggests a potential common link to KD that deserves scrutiny.

Characterization of Air Pollution Index and Its Affecting Factors in Industrial Urban Areas in Northeastern China

Characterization of Air Pollution Index and Its Affecting Factors in Industrial Urban Areas in Northeastern China

Reillumination about the Cultural Relics of the early Bronze Age in Northeastern area of China

Reillumination about the Cultural Relics of the early Bronze Age in Northeastern area of China

长白山云冷杉针阔混交林主要树种空间分布及其关联性

An observational field plot,covering an area of 60×60m,was established to analyze the spatial distributions and associations of the main tree species in a spruce-fir coniferous and broadleaved mixed forest in the Changbai Mountain area in northeastern China. The spatial coordinates,diameters at breast height( DBH),diameters at ground height( DGH) and heights( H) of all trees with a height exceeding 30 cm and a dbh less than 5 cm were measured. The univariate O-ring function was used to analyze the spatial distribution patterns of the main tree species while the bivariate O-ring function statistic was used to analyze intraspecific and interspecific relationships among different trees. The distribution of tree diameters at breast height( DBH) of the entire community and of individual tree species follows the shape of an inverse J,which is rather unexpected because the distribution of dbh's in these forests is usually bimodal. All the Abies nephrolepis and Acer mono trees show an aggregated spatial distribution at short distances and a random distribution at other scales while Picea koraiensis、Pinus koraiensis and Tilia amurensis are randomly distributed at all scales. At different growth stages,the main tree species have different spatial distributions. Seedlings and saplings of Abies nephrolepis and Acer mono are spatially aggregated at close ranges but show uniform or random distributions at large scales. Spatial associations between the seedlings,saplings and big trees were also studied. As expected,the intensity of the spatial aggregation is declining withincreasing dbh' s. With few exceptions,pairs of the five main tree species,show mostly positive association at short distances.

A new species of Cerchysiella (Hymenoptera: Encyrtidae) parasitic in larva of chestnut trunk borer (Coleoptera: Cerambycidae) from China with notes on its biology

A new species of Cerchysiella Girault (Hymenoptera: Chalcidoidea, Encyrtidae), Cerchysiella raddeii Yang, sp. nov., is described from China. It is a gregarious koinobiont endoparasitoid in mature larvae of the chestnut trunk borer, Massicus raddei (Blessig) (Coleoptera: Cerambycidae), a serious pest which causes severe damage to many oak tree species, particularly Quercus mongolica and Quercus liaotungensis (Fagaceae) in forested areas of northeastern China. The new species is one of the principal natural enemies of the wood borer and it has high potential as a biological control agent with parasitism rates of 6.7%, large numbers of adult wasps were reared from a single host larva (average 1083.8), and there is a high female : male sex ratio (9.67 : 1).

Research of Cover and Management Factor in the Model of the Revised Universal Soil Loss Equation of Black Earth Erosion in Northeastern Part of China

Solid vegetation roots may lead to the strong grip on the soil, thus they have a lot of positive effects, such as reducing both the rainfall kinetic energy and the amount of soil erosion, strengthening soil conservation and soil-reinforcement. Therefore, vegetation is a decisive factor in preventing soil erosion. Cover-management-C-factor is an important influential factor in The Universal Soil Loss Equation (USLE), determined mainly by such factors as vegetation coverage, situation of land utilization, productivity level, crop cultivation order, crop growing sequence, etc. So the value of Cover-management-C-factor is often difficult to estimate. Based on GIS technology, vegetation cover parameters drawn by SPOT statistics as well as field study, this research reveals the different land use types in the northeastern area of China so that the C-value of that area can be calculated through both formula and experimental assignment. Furthermore, by comparison of the two results, the C-value will be proved more precise and practical and thus its impact on soil erosion will provide more scientific basis for us.

Response of 50-year Regional Climatic Variation to Global Warming in the Desert Area of Northwestern China

The climate in desert is totally different from those in other landscapes. This paper, by analyzing the data collected in Minqin desert area during the period of 1961-2009, attempts to figure out how the temperature, precipitation and air humidity in the desert area of northwestern China respond to global warming. The result revealed that: the increasing rate of the mean annual temperature in Minqin during 1961-2009 was greater than that of the global average and that of the hundred-year average in China; whereas lower than that in the arid area in northeastern China in the recent 20 years. In Minqin, the temperatures in winter and spring rose significantly. The winter and spring temperatures and the annual maximum temperature showed big variations, with great fluctuations. The annual air humidity increased dramatically while the precipitation displayed an insignificant increasing trend. There was a significant correlation between air humidity rising and precipitation increasing. However, there’s no sound consistency between the periodic variations of air humidity and those of precipitation. The warmer spring usually induced intensive sandstorms, and the instability of air temperatures has caused yield reduction of crops/ fruits in the study area.

UPLC-MS based metabolic profiling of the phenotypes of Acanthopanax senticosus reveals the changes in active metabolites distinguishing the diversities of the plant grown in northeast area of China

ABSTRACT Acanthopanax senticosus (Rupr.et Maxim.) Harms. ( AS ) is a medicinal plant which mainly distributes in Northeastern area of China, due to the widely utilization in clinical and pharmaceutical industry, the wild resource of the plant is limited, the cultivation of the plant is in needed currently. Therefore it is of importance to select a medicinal priority for cultivating from two different sexual type of AS. In the present study, UPLC-MS technology-based metabolic profiles was used to discriminate phenotypes. By processing the metabolomic data with principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and orthogonal projection to latent structures (OPLS) analysis, eleven secondary metabolites were found to be responsible for classing the two varieties of Acanthopanax senticosus , they might be taken as potential biological markers of sexual type. These marker metabolites include flavone, coumarin, terpenes and organic acids, which are the main active constituents related to the therapeutic effects of Acanthopanax senticosus . Among these valuable secondary metabolites, flavone, anthraquinone and organic acids are highly expressed in short capillament Acanthopanax senticosus , while coumarin and terpenoid are highly expressed in the long capillament variety. As a result, by monitoring these highly expressed metabolites and through selective cultivation, an Acanthopanax senticosus with higher amounts of medicinally relevant constituents could be created.

Characterization of Atmospheric Organic and Elemental Carbon of PM2.5 in a Typical Semi-Arid Area of Northeastern China

ABSTRACTIn the spring of 2006, daily particulate matter (PM2.5) aerosol samples were collected in Tongyu, a semi-arid area in northeastern China. The concentrations of organic carbon (OC) and elemental carbon (EC) were determined with a thermal/optical carbon analyzer in the filter samples. The average concentrations of OC and EC in PM2.5 were 14.1 ± 8.7 and 2.0 ± 1.3 μg/m3, respectively. A good correlation between OC and EC was observed during the spring season, suggesting that they might be derived from similar sources. The correlation between OC and K+ was high (R = 0.74), and the K+/OC ratio, as determined from their linear regression slope, reached 2.57. The good correlation and high K+/OC ratio indicated that biomass-burning was probably one of the major sources of OC in this region. The concentrations of estimated secondary organic carbon (SOC) in PM2.5 in Tongyu ranged from below the detection limit to 26.1 μg/m3 (mean, 5.9 μg/m3). The percentages of SOC in OC and in PM2.5 mass were 42.0% and 2.1%, respectively. The SOC concentrations during dust storm (DS) periods were higher than those during non-dust storm (NDS) ones, suggesting that chemical reaction processes involving gas-particle conversion occurred during the long-distance transport of aerosol particles.

Outline of Air Pollution in an Industrial Area in Northeastern China (Shenyang)

Outline of Air Pollution in an Industrial Area in Northeastern China (Shenyang)

Preliminary description of diatom community and its relationship with water physicochemical variables in Qixinghe Wetland

Wetlands play a very important role in ecosystems. Qixinghe Wetland is a nature reserve area in northeastern China. In this paper, diatom communities and environmental qualities were investigated at eight sites in Qixinghe Wetland. This study was to examine diatom species patterns in relation to environmental variables in wetlands, and to use diatoms as indicators to water quality in wetlands and wetland classification. Diatoms were sampled in summers and autumns in 2002 and 2004, during which 180 taxa were identified. Environmental variations in pH, temperature, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) were measured. The seasonal composition and abundance of diatoms changed greatly during the study period. The relationship between diatoms and chemical water quality was estimated statistically. Canonical correspondence analysis (CCA) with forward selection and Monte Carlo permutation tests revealed that all water environmental variables changed during the study period (P <0.05). Among all the parameters, variation in BOD among the sites was a very important determinant of species composition according to the CCA, and BOD decreased from 2002 to 2004. Our results suggest that the water quality had improved during the three-year period because of enhanced environmental protection with less human disturbance. We conclude that diatoms can be used to indicate water quality and habitat conditions in this wetland.

Black carbon in a continental semi‐arid area of Northeast China and its possible sources of fire emission

Surface continuous measurements on black carbon (BC) were performed at Tongyu (44.42°N, 122.87°E) from March to December 2008. Tongyu is an international reference site of semi‐arid climate and environment researches, located in a continental semi‐arid area of northeastern China. Mass concentrations and potential contributing sources of BC are discussed for the sampling site. Hourly BC concentrations ranged from 77.61 ng m−3 to 59.55 μg m−3 with an average of 2.52 μg m−3, showing a clear seasonal pattern with high values in spring, fall, and winter and low values in summer. Events of high BC concentrations occurred frequently in spring as a result of long‐range transport of polluted air masses from the north, northwest, and south in the atmosphere over the Asian continent. The Yangtse River Delta (YRD) and China Anhui Province, the North China Plain (NCP), Northeast China, the Mongolian boundary near China and Russia, Middle Asia, and some areas of Russian Far East were major potential contribution sources for the observed pollutants. The region between Jiangsu Province and Anhui Province of China and the boundary regions between China and Russian Primorskiy and Khabarovskiy were possible source areas of fire emissions having great contributions to high BC levels at Tongyu. The region between Jiangsu Province and Anhui Province of China was the most important anthropogenic fire source of agricultural residue burning outflows.

Characteristics of mass concentrations depending on synoptic features during airborne dustfall episodes observed at Cheongwon in Korea in 2005

Sandstorms in the desert and loess regions of north China and Mongolia, as well as the associated dustfall episodes on the Korean Peninsula, were monitored in 2005. The ground mass concentrations of PM10 and PM2.5 were analyzed during dustfall episodes at Cheongwon, in central south Korea, based on synoptic features at surface, 850 hPa and 500 hPa levels. A total of seven dustfall episodes lasting eleven days were observed and the mass concentration ratios of PM2.5 and PM10 during dustfall episodes were classified into a severe dustfall episode (SDE) and a moderate dustfall episode (MDE) depending upon two synoptic features. The main synoptic feature was for SDEs, which occurred frequently under a surface anticyclone and cyclone located in the west and east of the Korean Peninsula with large amplitude trough at 500 hPa over the northern Korean Peninsula. The sandstorms at the source headed directly to Korea via a strong N-NW wind without passing through any large cities or industrial areas of east China. The PM10 mass concentration sharply increased during the SDEs; however, the fine aerosol fraction of PM2.5 levels was relatively low with 13.6% of the mass concentration. In a synoptic feature for MDEs, a slow moving cyclone headed to Korea via the industrial areas of northeastern China under a small amplitude trough at a 500 hPa level. A weak anticyclone was also located over China. MDEs showed low mass concentrations of coarse PM10 particles and large fraction of fine PM2.5 particles at 46.3%.

Development of freezing–thawing processes of foundation soils surrounding the China–Russia Crude Oil Pipeline in the permafrost areas under a warming climate

The proposed China–Russia Crude Oil Pipeline (CRCOP) will be subjected to strong frost heave and thaw settlement of the surrounding soil as it traverses permafrost and seasonally frozen ground areas in Northeastern China. The freezing–thawing processes, the development of the maximum frozen cylinder in taliks and thawed cylinder in permafrost areas, and the variations in the maximum freezing depths under the pipeline in taliks and thawing depths in different permafrost regions near Mo'he station, the first pumping station in China, were studied in detail using numerical methods in this paper. The inlet oil temperature at Mo'he station was assumed to vary from 10 to − 6 °C in a sine wave form during the preliminary design phase. Research results showed that the freezing–thawing processes of soils surrounding the buried pipeline had distinct differences from those in the undisturbed ground profile in permafrost areas. In summer, there was downward thawing from the ground surface and upward and downward thawing from the pipeline's surface once the temperature of the oil rose above 0 °C. In winter, downward freezing began from the ground surface but upward and downward cooling of the cylinder around the pipeline didn't begin until the temperature of the oil dropped below 0 °C. However, in the undisturbed ground profile, downward thawing from the ground surface occurred in summer and downward freezing from the ground surface and upward freezing from the permafrost table occurred in winter. The maximum thawing depths and thawed cylinder around the pipeline in warm permafrost enlarged with elapsing time and decreasing water content of the soils. In taliks, the maximum freezing depths and frozen cylinder around the pipeline kept shrinking with elapsing time and increasing water content of the soils. The freezing–thawing processes and development of the thawed and frozen cylinders around the pipeline were muted by any insulation layer surrounding the pipeline. Insulation had better thermal moderating on the heat exchange between the pipeline and the surrounding soils during the early operating period. But its role slowly weakened after a long-term operating. Research results will provide the basis for assessment and forecasting of engineering geological conditions, analysis of mechanical stability of the pipeline, foundation design, and pipeline construction and maintenance.

Atmospheric mercury in Changbai Mountain area, northeastern China II. The distribution of reactive gaseous mercury and particulate mercury and mercury deposition fluxes

Reactive gaseous mercury (RGM) and particulate mercury (Hgp) concentrations in ambient air from a remote site at Changbai Mountain area in northeastern China were intermittently monitored from August 2005 to July 2006 totaling 93 days representing fall, winter-spring and summer season, respectively. Rainwater and snow samples were collected during a whole year, and total mercury (THg) in rain samples were used to calculate wet depositional flux. A throughfall method and a model method were used to estimate dry depositional flux. Results showed mean concentrations of RGM and Hgp are 65 and 77 pg m(-3). Compared to background concentrations of atmospheric mercury species in Northern Hemisphere, RGM and Hgp are significantly elevated in Changbai area. Large values for standard deviation indicated fast reactivity and a low residence time for these mercury species. Seasonal variability is also important, with lower mercury levels in summer compared to other seasons, which is attributed to scavenging by rainfall and low local mercury emissions in summer. THg concentrations ranged from 11.5 to 15.9 ng L(-1) in rainwater samples and 14.9-18.6 ng L(-1) in throughfall samples. Wet depositional flux in Changbai area is calculated to be 8.4 microg m(-2) a(-1), and dry deposition flux is estimated to be 16.5 microg m(-2) a(-1) according to a throughfall method and 20.2 microg m(-2) a(-1) using a model method.

Development of a new index for integrating landscape patterns with ecological processes at watershed scale

Understanding the relationship between landscape patterns and ecological processes has been a central yet challenging research theme in landscape ecology. Over the past decades, many landscape metrics have been proposed but few directly incorporated ecological processes. In this paper, we developed a landscape index, namely, location-weighted landscape index (LWLI) to highlight the role of landscape type in ecological processes, such as nutrient losses and soil erosion. Within the framework of the Lorenz curve theory, we develop this index by integrating landscape pattern and point-based measurements at a watershed scale. The index can be used to characterize the contribution of landscape pattern to ecological processes (e.g. nutrient losses) with respect to a specific monitoring point in a watershed. Through a case study on nutrient losses in an agricultural area in northeastern China, we found that nutrient losses tended to be higher for a watershed with a higher LWLI value, and vice versa. It implied that LWLI can be used to evaluate the potential risk of nutrient losses or soil erosion by comparing their values across watersheds. In addition, this index can be extended to characterize ecological processes, such as the effect of landscape pattern on wildlife inhabitation and urban heat island effect. Finally, we discuss several problems that should be paid attention to when applying this index to a heterogeneous landscape site.

Atmospheric mercury in Changbai Mountain area, northeastern China I. The seasonal distribution pattern of total gaseous mercury and its potential sources

An intensive field campaign for the measurement of total gaseous mercury (TGM) concentrations in ambient air was conducted in Changbai Mountain area from 5 August 2005 to 5 July 2006 using an automatic atmospheric mercury analyzer (Tekran 2537A), which was the first time TGM was monitored at a remote area in northeastern China. 99% of the hourly TGM concentrations fell between 1.28 and 9.49 ng m −3 with an annual arithmetic mean of 3.58±1.78 ng m −3, which was significantly elevated compared to values obtained in remote areas of Europe and North America. Seasonal mean TGM concentrations displayed a descending trend as follows: winter, spring, fall, and summer. Compared to spring/winter, TGM concentrations were lower in the summer/fall but the standard deviation (SD) of TGM levels was higher and indicated a correlation with anthropogenic emissions. TGM concentrations showed seasonal differences with respect to meteorological parameters: TGM levels in spring/winter were most correlated with wind speed, and correlated with solar radiation only in the winter, while TGM levels in summer/fall periods were most correlated with air temperature. There was a strong diurnal variation of seasonal TGM with significantly higher concentrations in daytime/nighttime compared to the early morning. The seasonal diel TGM pattern indicated regional biofuel and coal combustion were the primary mercury sources.