Search

In recent years, global attention to forest ecological environment, carbon, wood yield, and biodiversity has been increasing, which requires forest managers to make reasonable forest planning in time and space to meet the needs of multiobjectives and multi-resources. In this study, the resources of business units in Northeast China were analyzed, and the FPS-ATLAS model was established. A multi-objective decision supporting spatial forest planning scheme for 16629.53 ha of forest in Jingouling forest farm of Wangqing Forestry Bureau in Jilin Province was proposed. In this paper, the volume growth model of six forest types was established, and the carbon storage model was introduced to show the total carbon, biomass carbon, dissolved organic carbon, and total soil carbon of the ecosystem. The dynamic change in carbon during the whole planning period has achieved good results. After 20 time periods, the total soil carbon increased to 7,627,208 Mg (+6.63%), the total ecosystem carbon increased to 14,889,876 Mg (+27.51%), the biomass carbon increased to 5,362,779 Mg (+59.70%), and the dissolved organic carbon increased to 9,531,906 Mg (+14.59%). The purpose of this article is to achieve dynamic management of forest resources, meet multiple constraint settings, achieve multiple management objectives, harvest wood products, and ensure the ecological and social functions of forests so that forests ultimately achieve the ideal state of sustainability. [ABSTRACT FROM AUTHOR]

The seasonal characteristics of fluorescence components in CDOM for lakes in the semi-arid region of Northeast China were examined by excitation-emission matrices fluorescence and parallel factor analysis (EEM-PARAFAC). Two humic-like peaks C1 (Ex/Em = 230, 300/425 nm) and C2 (Ex/Em = 255, 350/460 nm) and two protein-like B (Ex/Em = 220, 275/320 nm) and T (Ex/Em = 225, 290/360 nm) peaks were identified using PARAFAC. The average fluorescence intensity of the four components differed with seasonal variation from June and August 2013 to February and April 2014. The total fluorescence intensity significantly varied from 2.54 ± 0.68 nm-1 in June to the mean value 1.93 ± 0.70 nm-1 in August 2013, and then increased to 2.34 ± 0.92 nm-1 in February and reduced to the lowest 1.57 ± 0.55 nm-1 in April 2014. In general, the fluorescence intensity was dominated by peak C1, indicating that most part of CDOM for inland waters being investigated in this study was originated from phytoplankton degradation. The lowest C2 represents only a small portion of CDOM from terrestrial imported organic matter to water bodies through rainwash and soil leaching. The two protein-like intensities (B and T) formed in situ through microbial activity have almost the same intensity. Especially, in August 2013 and February 2014, the two protein-like peaks showed obviously difference from other seasons and the highest C1 (1.02 nm-1) was present in February 2014. Components 1 and 2 exhibited strong linear correlation (R² = 0.633). There were significantly positive linear relationships between CDOM absorption coefficients a(254) (R² = 0.72, 0.46, p < 0.01), a(280) (R² = 0.77, 0.47, p < 0.01), a(350) (R² = 0.76, 0.78, p < 0.01) and Fmax for two humic-like components (C1 and C2), respectively. A close relationship (R² = 0.931) was found between salinity and DOC. However, almost no obvious correlation was found between salinity and EEM-PARAFAC extracted components except for C3 (R² = 0.469). Results from this investigation demonstrate that the EEM-PARAFAC technique can be used to evaluate the seasonal dynamics of CDOM fluorescence components for inland waters in semiarid regions of Northeast China. [ABSTRACT FROM AUTHOR]

Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on CH4 emissions and ecosystem respiration (Reco) from five coastal wetlands in the Liaohe Delta, northeast China: two Phragmites australis (common reed) wetlands, two Suaeda salsa (sea blite) marshes and a rice (Oryza sativa) paddy. Throughout the growing season, the Suaeda wetlands were net CH4 sinks whereas the Phragmites wetlands and the rice paddy were net CH4 sources emitting 1.2-6.1 gCH4m-2 y-1. The Phragmites wetlands emitted the most CH4 per unit area and the most CH4 relative to CO2 . The main controlling factors for the CH4 emissions were water table, temperature and salinity. The CH4 emission was accelerated at high and constant (or managed) water tables and decreased at water tables below the soil surface. High temperatures enhanced CH4 emissions, and emission rates were consistently low (< 1mgCH4 m-2 h) at soil temperatures < 18 °C. At salinity levels> 18 ppt, the CH4 emission rates were always low (< 1mgCH4 m-2 h-1) probably because methanogens were outcompeted by sulphate reducing bacteria. Saline Phragmites wetlands can, however, emit significant amounts of CH4 as CH4 produced in deep soil layers are transported through the air-space tissue of the plants to the atmosphere. The CH4 emission from coastal wetlands can be reduced by creating fluctuating water tables, including water tables below the soil surface, as well as by occasional flooding by high-salinity water. The effects of water management schemes on the biological communities in the wetlands must, however, be carefully studied prior to the management in order to avoid undesirable effects on the wetland communities. [ABSTRACT FROM AUTHOR]

In China's pursuit of modernization, the government has introduced the rural revitalization strategy to combat rural decline, foster balanced urban–rural development, and reduce the urban–rural gap. Rural human settlements, as key components of this strategy, play a vital role. This paper examines the types and characteristics of human–earth relationships within rural settlements, emphasizing their significance. Using national land use and population census data, we analyze the spatiotemporal evolution of rural settlements at the county level, investigating landscape pattern changes, assessing the degree of coupling coordination between rural population and settlements, categorizing relationship types and features, and estimating the potential for remediation. Our findings reveal a growing trend in the scale of rural human settlements, particularly sourced from arable land, with significant expansions observed in the North China Plain and Northeast Plain, indicating potential for farmland reclamation and village consolidation. Landscape patterns of rural human settlements exhibit increased fragmentation, complex shapes, and aggregation. We categorize the utilization of rural human settlements into two types, each with four distinct features: human–land coordination is observed in regions characterized by either a higher rural population and larger rural settlement areas, or lower rural population and smaller rural settlement areas. Human–land trade-offs are evident in areas where there is either a higher rural population and smaller rural settlement areas, or lower rural population and larger rural settlement areas. This provides valuable insights for the Chinese government's context-specific implementation of the rural revitalization strategy. It also serves as an experiential reference for the governance of rural human settlements in other developing countries. [ABSTRACT FROM AUTHOR]

This paper explores the placement and function of the discipline of geography in the expansion of the Japanese empire, doing so through the prism of the work and field research of Tada Fumio, a leading geographer in Japan both before and after 1945. This examination of this aspect of Tada Fumio's career and its interweaving with the construction and consolidation of Japan's empire will broaden recent studies of imperial Japan's simultaneous encounter with geopolitics and fascism while engaging with Japan's developing ideas about geography as a political and cultural discipline. This paper demonstrates the importance of the entwined histories of Japanese and German geographers in the Japanese empire, as well as documenting Tada Fumio's activities in Manchuria (northeast China) and on the Korean peninsula. Finally, the paper reveals fissures in the historical record of Japanese geographers in continental Asia and, until such time as more subaltern voices can be found, seeks to lay down the foundation for further research on the study of geography in the Japanese empire. • Connections between German, Japanese and Korean Geographers prior to 1945. • Teaching and research in academic geography in the Japanese Empire. • Tada Fumio's connections with Keijo Imperial University, colonial Korea and Japanese Empire. • Field work expeditions including Tada Fumio to Manchuria and Mengjiang. [ABSTRACT FROM AUTHOR]

This paper examines the life of Christian Socialist Kim Chang‐joon and explores the themes of independence, liberation, reunification, and peace between both Koreas. It divides Kim's life into four stages: his participation in the March First Movement, his involvement in Christian socialism, his practice of social thought in Manchuria, and his activities toward reunifying the two Koreas after liberation from Japanese colonial rule. In the first phase, Kim became an active nationalist. His national consciousness developed into Christian socialism through his pastoral work. When he experienced Japanese colonial oppression while working with this ministry, he abandoned religious life and focused on socio‐political activism in Manchuria. He founded the Christian Democratic Alliance and participated in the Democratic National Front to reunite the two Koreas after liberation. This article demonstrates how Kim set an example for how churches and Christians can strive for and attain liberation, reunification, and peace in the Korean context. [ABSTRACT FROM AUTHOR]

River water irrigation is used to reduce soil salinity in the reed fields of the Shuangtai Estuary Wetland in Northeast China to improve the reed quality for paper industry; however, quantitative effects of this approach have not yet been investigated. In this study, the effect of irrigation was investigated by conducting comprehensive field observations and numerical simulations, and the necessary irrigation water volume was determined. The field observations included determination of (1) the relation between surface soil salinity and reed yield; (2) vertical profile of soil salinity before and after the irrigation period; and (3) variation of depth and salinity of the standing water during irrigation and the rate of rainwater interception by reed leaves. Our findings suggested that (1) the reed yield decreased remarkably when the surface soil salinity exceeded 5‰ and (2) irrigation could reduce salinity to below this level. From our observations, water budget in the irrigated reed fields was evaluated. A numerical model was constructed to simulate the salinity reduction process by assuming that the salinity flux across the ground surface was proportional to the salinity difference between the standing water and the surface soil. The model parameters were calibrated using the results of observation (3) such that the model successfully reproduced the observed time series of standing water salinity. A series of numerical experiments were performed using the model to determine the irrigation water volume necessary for sufficient soil salinity reduction. The results suggested that soil salinity reduction depended greatly on rainfall during the reed growth period. Further, an initial irrigation depth of about 20 cm was sufficient for lowering the salinity to 5‰ even during rainfall shortage that occurred every 10 years on an average. Replacing the saline standing water before intensive rainfall events with rainwater was found to be an effective approach to lower the surface soil salinity. [ABSTRACT FROM AUTHOR]

This paper examines the long‐ and short‐run impacts of the railway zones associated with the China Eastern and South Manchuria Railways in Manchuria, which were administered by Russia and Japan, respectively, from the early 1900s to the 1920s. Despite the fact that 'railway imperialism' impaired China's sovereignty and territorial integrity and constituted a humiliating quasi‐colonial episode in Chinese history, railway zones nevertheless had a noticeable impact on Manchuria's local economies. Through a reconstruction of the historical dataset and cliometrics, we show that, among the railway zones in northeastern China, only those attached to the South Manchuria Railway exerted a significant and positive impact. Specifically, its railway zone had higher urbanisation and literacy rates and a higher percentage of professionals in its industrial and commercial sectors in the 1930s, and these effects persist to the present day as an unintended outcome. Apart from the agglomeration of direct manufacturing investment in these railway zones, an additional channel through which the impact took effect was the provision of public goods, such as schools and hospitals, which served as necessary conditions for long‐term development. This study sheds light on understanding the persistence of colonial history as a root of development. [ABSTRACT FROM AUTHOR]

In recent years, the frequent occurrence of extreme climate disasters has seriously affected agriculture in Northeast China. Based on precipitation data derived from 83 geographical stations in the study area for 60 years (1960–2019), we chose the reliable statistical methods of the Mann–Kendall test, Sen's slope, and the Standardized Precipitation Index, and regarded drought and flood as a whole in this paper, to identify the temporal and spatial variation characteristics of precipitation and extreme climate events in Northeast China. The results show that an increasing trend of disasters was detected at the 95% confidence level (Z = 2.3). According to the timescale analysis, abrupt climate changes started in 2006. Temporal and spatial distribution of extreme climate disasters, mainly drought and flood disasters, showed a significant upward trend from 2006 to 2019. According to the spatial analysis, the precipitation in Northeast China decreased from south to north and fluctuated less from east to west. Moreover, stations with extreme climate trends (trend of climatic anomaly with confidence level > 90%) followed the same spatial pattern as those with a high frequency of extreme climate disasters (more than 17.87 times/decade). The severity and frequency of extreme climate have increasingly threatened Northeast China in the past decade. In particular, the Northeast Plain experienced the most severe and extreme climate events that seriously threatened the study area in 2007, 2009, 2010, and 2019. Our results highlight the urgent need for the development of monitoring and early warning of droughts and flood disasters to reduce economic losses. [ABSTRACT FROM AUTHOR]

The paper discusses the etymological connection between Amuric * alr 'berry' and Mongolic * alïr-su/n 'lingonberry'. The two items represent the common root * alïr and must reflect a trace of language contact. However, unlike several other lexical items shared by Amuric and Mongolic, this word is not attested in Tungusic, except as a very late and localized secondary borrowing from Mongolic. This means that the connection may be due to a relatively old direct contact between Pre-Proto-Amuric and Pre-Proto-Mongolic. This, in turn, has implications to the question concerning the prehistorical locations of the Amuric, Mongolic, and Tungusic language families in southern and central Manchuria. [ABSTRACT FROM AUTHOR]

This paper focuses on the interdecadal variation in drought in Northeast China (NEC) in recent decades. Two dry and wet periods have occurred in the past 61 years (1950–2010). The mechanism underlying the interdecadal variation in drought in NEC is further analyzed; the results indicate that the direct cause is the interdecadal change of the Okhotsk High (OH). A strong (weak) OH is conducive (detrimental) to the convergence of cold air transported by northeast cold vortex and water vapor from the east of NEC, eventually leading to an increase (decrease) in precipitation. Furthermore, we seek to understand why OH displays such an interdecadal variation. The interdecadal increases and decreases in sea ice in the Barents Sea and the Kara Sea explain most of the interdecadal change of the OH. When more sea ice is present in this area, more energy is transferred eastward from the sea ice area to Northeast Asia, weakening the OH; in contrast, less sea ice strengthens the OH. Sensitivity simulations by Community Atmosphere Model, version 4 (CAM4) using sea ice forcing in the Barents Sea and the Kara Sea yield similar results to the observed data, further confirming our conclusion. The results of this paper provide a new understanding of the interdecadal variation in drought in NEC, and it may help to improve our ability to predict drought and provide early warning in the future. Key Points: The drought over Northeast China has significant interdecadal variability during the past decadesThe Okhotsk High acts as the direct factor causing interdecadal changes in NEC drought by affecting atmospheric circulationThe interdecadal increases and decreases in sea ice in the Barents Sea and the Kara Sea can modulate the Okhotsk High changes [ABSTRACT FROM AUTHOR]

This paper examines the possibility that the earlier homeland of the Ghilyak language(s), collectively identified as the Amuric language family and today spoken in the Lower Amur basin and on the island of Sakhalin, was located further south in Central Manchuria. It may be assumed that the Amuric linguistic lineage moved northwards along the Sungari-Amur basin under the pressure of the Tungusic languages spreading from the south along the same route. It is possible that traces of the former presence of Amuric in Central Manchuria are preserved in the names of the large rivers of the region, notably the Sungari and Ussuri. It is also possible to postulate a political context for the linguistic expansions of both Amuric and Tungusic in the framework of protohistorical Manchuria. In this framework, the origins of the Amuric language family may with some likelihood be linked to Puyŏ, the first historically known political state in the region. [ABSTRACT FROM AUTHOR]

The Sibe of Xinjiang have been recognized as speakers of a Manchu variety by linguists. However, for the Sibe speakers themselves, the situation is more complicated. For certain reasons, the Sibe often present themselves as a group whose historical origins are different from the Manchus. Several mentions occur in historical sources about Sibe being vassals to the Khorchin Mongols before "becoming Manchus". This has been used among the arguments for the non-Manchu identity of the Sibe. In recent years, academic discussion has focused on the ethnic identity of the Manchus, and, to a lesser extent, also on the position of the Sibe in relation to the Manchus. In this paper I try to select out features of possible Khorchin, i.e. eastern Mongolian, origin, in Sibe which may have come from direct language contact. I discuss several morphological features of Mongolic origin which seem not to be shared by other Manchu varieties, and one remarkable Sibe feature of Khorchin origin (the emphatic prefix me-). In addition, I mention the existence of lexical evidence of direct contact which is found in more conservative layers of Sibe vocabulary. Another question concerns the significance of this evidence for imagining the Sibe history. The linguistic situation in central Manchuria during the period concerned (15th-16th centuries) suggests that if the shared features indeed come from this period, they may rather be remnants of an extinct linguistic environment characterized by intense Mongolic-Tungusic contacts than of bilateral contact between two distinct groups - Khorchins and Sibe. [ABSTRACT FROM AUTHOR]

The wartime shōkokumin discourse of Japan rested on two competing premises, each catenated with a different part of the compound word: the "shō" that emphasized children's immaturity and vulnerability and the "kokumin" that activated them immediately as mobilizable citizens. This paper charts how the tensions innate in shōkokumin discourse became manifest both at home and in the colonial territories abroad, focusing especially on the exceptionally ambiguous category of settler children in Manchuria. By employing settler children's tsuzurikata essays from the late 1930s and early 1940s as a central source of examination, the current study fleshes out the particulars of their lives in Manchuria – the trials and tribulations, as well as the privileges and prestige. Neither metropolitan shōkokumin nor colonial kōmin, the settler children in Manchuria had the double duty of becoming Manchurian and Japanese, embracing their role as the gatekeepers of Japan's Manchuria. Ranging from language acquisition and assimilating into local customs to declaring Japanese ethnic membership, settler children's writings expose how they articulated their relationship to the naichi metropole, and emphasized their identities as Japanese kokumin. Whether these children ever gained legitimate status as imperial shōkokumin during the turmoil and exigencies of war remains an unresolved question; however, what is clear is that the shōkokumin discourse itself operated as an imperial pedagogy, binding settler children to their double duties while not necessarily guaranteeing their rights at war's end. [ABSTRACT FROM AUTHOR]

For most of Qing domination over China, the Manchu rulers strictly controlled or even prohibited migration of Chinese people to the dynasty's Motherland (long xing zhi di 龍興之地). Only two brief phases are an exception, namely the mid Shunzhi to early Kangxi and Yongzheng periods. During the former, in 1653, a "Regulation for the repopulation and land reclamation of Liaodong" was promulgated, establishing alluring incentives for whoever managed to move a hundred or more people to the region east of the Liao river. Only fifteen years later, when the maneuver had just started to produce some results, the Qing court abolished it. In the long term, such a change of direction appears perfectly normal, considering that later on most of the lands would be assigned to the Eight Banners and the state would have striven to keep the Chinese out. Nevertheless, in the short term, the decision seemed to come out of the blue. An interesting debate on what might have determined the turnabout began in the early twentieth century, and some most recent contributions have been published in the 2000s; yet none of the thesis proposed so far is fully convincing. On the basis of sources that have not yet been taken into account, this paper further investigates into the matter and aims at demonstrating that the concerns which compelled the rulers to officially oppose immigration in the following decades already existed in the very first years of Kangxi reign. [ABSTRACT FROM AUTHOR]

This paper presents new research on a lacustrine anoxic event (LAE). These data include stable carbon isotope (δ13Corg), pyrite sulfur isotope (δ34Spy), trace element and biomarker ratios from the Hongmiaozi Basin (North China) and unravel the response of continental lakes under the influence of early Aptian extreme climate conditions. According to the stratigraphic chronology (122–118 Ma) and carbon isotope correlations, terrestrial sediment was influenced by the early Aptian Oceanic Anoxic Event (OAE1a). The results show that the Xiahuapidianzi Group experienced a significant warming process under negative excursions in carbon isotopes due to the influence of increased carbon dioxide partial pressure (pCO2). The climate varied from warm and humid to hot and arid (high Sr/Cu, low Rb/Sr, calcareous mudstone), the evaporation and salinity increased (high Sr/Ba and B/Ga), and land input sources decreased (low Zr, Ti and Th). Moreover, high total organic carbon (TOC) content was source from bacteria, algae (n-alkanes), and euxinic depositional environments (Pr/Ph, Cu/Zn and U V Mo). In the stage of continuous carbon isotopes positive excursion, organic matter accumulated rapidly. A paleolake environment model has provided a better understanding of current global climate issues under global warming caused by increased carbon dioxide concentrations. [ABSTRACT FROM AUTHOR]

This article discusses the dynamic changes in ethnic relations that have taken place in the Joseonjok (Chaoxianju) community comprising minority Koreans residing in and around Yanbian, an autonomous prefecture in northeastern China, and discusses the implications of those changes for the region. The main focus is on how the tension between China's fluctuating ethnicity-related politics and this diaspora group's continual struggle for a collective identity has been managed and internalised. Contrary to existing studies on the Joseonjok, the paper argues that the group has experienced de-ethnicisation, both as a top-down (government policy) and bottom-up (diaspora's reaction) process, rather than ethnic revival. The puzzling question is how and why de-ethnicisation occurs despite the commonly accepted conditions of ethnonationalism and, more recently, with trans-nationalism, heavily influenced by their Korean motherlands. Based primarily on ethnographical research and using a multiculturalism approach, this paper argues that the recent policy failure in dealing with multiculturality in China, together with the changing geopolitics of the region, has accelerated the process of de-ethnicisation. Joseonjok society's particular way of resisting political pressures and coping with ethnic tension in fact reflects a diaspora's common struggle to achieve integration with mainstream society while ensuring recognition of its own distinctive characteristics. [ABSTRACT FROM AUTHOR]

Borderland studies are revising the historiography of imperialism in China. Two representative examples are reviewed here that insightfully consider the equivocal effects of Russian and Japanese influence on the formation of Chinese and Korean national space in northern Xinjiang and the Sino-Korean border. In this altered narrative of nation-state formation, however, indigenous peoples remain marginal to the discussion. This essay discusses the following works. Judd C. Kinzley. Natural Resources and the New Frontier: Constructing Modern China's Borderlands. Chicago: University of Chicago Press, 2018. 234 pp. $105.00 (cloth), $35.00 (paper). | Nianshen Song. Making Borders in Modern East Asia: The Tumen River Demarcation, 1881–1919. Cambridge: Cambridge University Press, 2018. 303 pp. $99.99 (cloth), $30.99 (paper). [ABSTRACT FROM AUTHOR]

To further improve the accuracy of regional-residual separation of potential field data set, this paper presents a novel computation scheme based on different attenuation rate of the fields induced from deep and shallow sources respectively. For the new scheme, the observations are first upward continued to a plane above it to get an updated field. Then, the difference between the original field and the updated field is calculated. Next, a controlling parameter is set to select those data points whose amplitudes have been much reduced. The adverse effects from the residual anomalies on the fitting of the regional trend can be reduced by removing the identified local points from the original field. Finally, a low-order polynomial is utilised for approximating the regional trend, and the corresponding residual field can be obtained by simple subtraction. Compared with gradient-based methods, the proposed new scheme has better noise adaptability for distinguishing different anomalies. The accuracy of the presented scheme was tested on synthetic data with and without noise. All tests showed that the new scheme reduces subjectivity and inaccuracy of the conventional methods significantly. In addition, the scheme was applied to Bouguer gravity anomaly of the Dida orebodies in Jilin Province, northeast China. This application also verified the superiority of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper explores the complexity of translation of borderland literature through a case study of the Japanese and Chinese translations of the Korean short story "The Red Hill." Written by the renowned Korean writer Kim Tong-in (김동인, 1900–1951) in 1932, this story features the Korean agrarian community in the Northeast Asian borderland of Manchuria and is conventionally considered a masterpiece of Korean national literature. When it was translated into Japanese and Chinese and anthologized in inland Japan and the Japanese Manchukuo respectively, the three texts of the same story in three languages conveyed different and contradictory national/imperial claims over Manchuria, a Northeast Asian frontier. This case study demonstrates how the very act of translating and anthologizing, as a process of linguistic transposition across cultural and national constituencies, may crystallize the sense of territorial competition through revealing, reshuffling, and redefining the covert intricacy of national relations in the original text. [ABSTRACT FROM AUTHOR]

This article shows how wartime conditions transformed the waste business in Japan. Hygiene regulations from 1900 to the 1920s followed by an influx of Korean migrant labour disrupted the traditional waste trade. The conquest of Manchuria opened up new export markets for Japanese waste and increased the demand for munitions, causing scrap metal prices to skyrocket. These new economic conditions created opportunities for Korean-owned waste businesses. In 1938 the Japanese Ministry of Commerce and Industry imposed a control system on kuzuya scrap dealers consciously modelled on Nazi Germany to keep scrap prices as low as possible and to prevent criminal activity through extensive surveillance. These price controls privileged wholesalers and harmed waste-pickers; Koreans remained in the trade because of their cheap labour. Economic mobilization under conditions of total war after 1941 temporarily rehabilitated the marginalized image of kuzuya in government propaganda, but the end of the war shattered that illusion. [ABSTRACT FROM AUTHOR]

In this paper, hindcast experiments were carried out on the snowfall that occurred on 12-13 April 2010 in Northeast China using the WRF model. Three land surface parameterization schemes (Noah, Noah-MP, and SSiB) and three microphysics schemes (WSM5, Lin, and CAM5.1) were chosen for nine ensemble members. The results indicate that spatial distribution of snowfall is sensitive to the choice of land surface schemes. The Noah-MP land surface scheme yields the smallest spatial distribution among the three land surface schemes. The simulations with the Noah and Noah-MP land surface schemes are better than those with the SSiB land surface scheme in terms of spatial correlation coefficient. Microphysics schemes have an influence on snowfall amount in the nine simulation experiments. The Lin and CAM5.1 microphysics schemes lead to much less snowfall than the WSM5 microphysics scheme. Overall, the ensemble means of simulations with three different land surface schemes can capture the features of snowfall distribution, especially when combined with the CAM5.1 microphysics scheme. [ABSTRACT FROM AUTHOR]

This paper looks at the problems faced by the Chinese silver-backed currencies in Manchuria during the period of Northern Expedition (1925–1928), the Chinese attempt to overcome these problems, and the reasons for its failure. Manchuria was a peculiar territory during the interwar period (1919–1939), where several currencies, backed by silver or gold, competed against one another. The Chinese silver banknote, first introduced at the turn of the twentieth century, was challenged by gold-backed Japanese yen issued by the Bank of Korea, and by the Russian ruble. This competition was set in the context of the struggle for political control over the area between China (the Qing Dynasty and its successor, the Chinese Republic), Russia (and its successor the Soviet Union), and the Japanese Empire, as well as the war between the southern Nationalists (Kuomintang) and the militarists (warlords) who controlled the Chinese central government in Beijing and Manchuria. This paper suggests that the difficult financial situation determined the course followed by the warlords, and that their failure was the result of the complex regional context, and the failures in their military strategy rather than of their fiscal policy. [ABSTRACT FROM PUBLISHER]

In this paper, we report new whole-rock geochemical and zircon U-Pb data for monzogranites in the NE Xing’an block. These data constrained the petrogenesis of C type (high Sr/Y) adakitic rocks and showed the spatial extent of the influence of the Mongol-Okhostsk ocean tectonic regime and the collision between the Jiamusi Massif and Songliao Terrane. New zircon laser-ablation inductivity coupled plasma mass spectrometry (LA-ICP-MS) U-Pb data indicated that the monzogranites in the studied area were emplaced in the Early Jurassic (~180 Ma). These rocks were characterized by unusally high SiO2 (≥67.49), and Sr (461-759 ppm), but strikingly low Y (4.63-8.06 ppm) and HREE (∑HREE = 3.83-6.49 ppm, Yb = 0.5-0.77 ppm) contents, with therefore high Sr/Y (67.2-119) and (La/Yb)N (29.7-41.5) ratios, showing the geochemical characteristics of C type adakitic granite. The data displayed negligible Eu anomalies (Eu/Eu* = 0.77-1.08), LREE-enriched and pronounced negative Nb and Ta anomalies. The C-type adakites in the studied area were most likely derived from the partial melting of a thickened lower continental curst. The magma source is most likely dominated by amphibolites and garnet amphibolites. In combination with previously-reported data from igneous rocks from the Mesozoic in NE China, we conclude that the Xing’an block was influenced by the Mongol-Okhotsk subduction tectonic system, and experiences compressive settings from the amalgamation of the Jiamusi block in the east of the CAOB. [ABSTRACT FROM AUTHOR]

Under the constraints of limited spaces and imbalanced traffic volumes (for both in and out directions) of container gates, reversible lane layouts become an economical and practical way to improve the service level of container terminal systems and make the maximum use of the current terminal resources. Together with a consideration of minimized total costs (both construction and operating) of terminal gate system, this paper first developed an optimization model to decide the number and scheduling rules of the reversible lanes at a terminal gate. A metaheuristic algorithm was built to solve the optimal model. Meanwhile, to reflect the randomness and dynamics property of the terminal gate system in practice, parameters that cannot be calculated from conventional analytic methods are obtained through a simulation model. Finally, a hub container terminal in the northeast of China was employed to verify the effectiveness of the proposed method and provide a theoretical foundation for the construction and management of terminal gate systems. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) pose a significant global concern, requiring a multifaceted approach to their risk assessment procedures, especially concerning their characteristics in the environment. The Horqin Left Middle Banner in Northeast China was chosen for the research region to investigate the abundance, composition, distribution, and ecological impact of MPs in surface agricultural soils. The concentrations of MPs ranged from 300 to 12800 items/kg, with a median concentration of 1550 items/kg (average = 1994 items/kg). The normal-sized MPs (500–5000 µm) had a higher relative abundance than small MPs (<500 µm). MPs were mainly derived from textiles and packaging and were affected by atmospheric transportation. Rayon and PET fibers were the main polymers identified. Furthermore, the potential environmental risks posed by the fundamental characteristics (abundance, chemical composition, and size) of MPs were quantified using multiple risk assessment models. The conditional fragmentation model indicated a propensity for MPs to degrade into smaller particles. Ecological risk assessments using pollution load index, pollution hazard index, and potential ecological risk index models revealed varying levels of risk. This study conducted a comprehensive assessment of the ecological risks of MPs based on their environmental characteristics, emphasizing the importance of considering multiple factors in the risk assessment process. This study investigates the occurrence, distribution, and ecological risk of microplastics (MPs) in agricultural soils of the Northeast Plain of China, a major food production area. MPs are persistent organic pollutants that can pose threats to soil health, crop quality, and food security. By analyzing the composition, size, and source of MPs, as well as their fragmentation and stability in soil, this study provides valuable data for assessing the environmental risk of MPs in agricultural regions. The study also suggests strategies for mitigating MPs pollution and protecting soil ecosystems. [Display omitted] • Evaluated the occurrence, distribution, and risks of MPs based on their properties. • Most MPs are normal-sized (>500 µm) and tend to break into smaller pieces. • MPs mainly derived from textiles and packaging (Rayon and PET, and coated paper). • The featured high-risk sites are mainly caused by polyacrylonitrile. [ABSTRACT FROM AUTHOR]

• This paper proposes a multi-dimensional assessment framework for cropland use stability. • Multi-dimensional cropland use characteristics present significant spatial differentiation. • Cropland stability in Northeast China Plain and Loess Plateau is the highest and lowest. • Urbanization will lead to about 9.31% of high-stability cropland losses in 2030. • Integrating landscape stability and national planning can draft a sustainable-oriented strategy. Shifting to more sustainable use can curb cropland resource degradation and improve production resilience. However, most cropland use assessments are unilaterally focused on biophysical levels and productivity, ignoring the multi-dimensional aspects of degraded cropland. This study attempts to describe cropland use stability in China by proposing a multi-dimensional assessment framework (including quantity, quality, management, service, and risk) to provide a reference for designing land degradation-neutral strategies. Results show that multi-dimensional cropland use characteristics present significant spatial heterogeneity. Western regions are reserve resource agglomerations that can replenish cropland quantity. In contrast, main grain-producing areas cover most current resources with preferably cultivation quality, management efficiency, and ecosystem services, while risk resistance is weak (especially in Middle-lower Yangtze Plain). Generally, the stability of cropland use in Northeast Plain is the highest and in Loess Plateau the lowest. Besides, urbanization will occupy about 9.31% of the high-stability cropland in 2030, of which 70.29% will occur in Northeast Plain and Huang-Huai-Hai Plain. The total potential productivity loss in Huang-Huai-Hai Plain alone will reach 100.1 kt, equivalent to supplying the food demand of 199,200 people annually. Therefore, a sustainable-oriented refined cropland management strategy should be designed according to the hierarchical nested spatial layout of comprehensive planning-stability map-multi-dimensional utilization characteristics to ensure the loss-replenishment balance and stable production. [ABSTRACT FROM AUTHOR]

Long-term dynamics of population decline can improve the conservation perspectives and strategies for endanger species. In China, new gazetteers having systematic compilation and wide geographical coverage can be considered as an important complementary for reconstruction historical distribution. For historical and cultural reasons, an endangered species-lynx ( Lynx lynx) was recorded regularly in new gazetteers. Therefore, the aim of this paper was to evaluate the population distribution in Northeast China from the 1950s to 2014. The data show that Felis lynx was widely distributed in Northeast China in the 1950s, but the number of the occurrence records have been significantly reduced by 85.6% in the last 60 years. This research also enlightens us that the new gazetteers can contribute to data shortage and it would be helpful to conservation biology. [ABSTRACT FROM AUTHOR]

Nowadays, environment problem has become the international hot issue. Experts and scholars pay more and more attention to the energy efficiency. Unlike most studies, which analyze the changes of TFEE in inter-provincial or regional cities, TFEE is calculated with the ratio of target energy value and actual energy input based on data in cities of prefecture levels, which would be more accurate. Many researches regard TFP as TFEE to do analysis from the provincial perspective. This paper is intended to calculate more reliably by super efficiency DEA, observe the changes of TFEE, and analyze its relation with TFP, and it proves that TFP is not equal to TFEE. Additionally, the internal influences of the TFEE are obtained via the Malmquist index decomposition. The external influences of the TFFE are analyzed afterward based on the Tobit models. Analysis results demonstrate that Heilongjiang has the highest TFEE followed by Jilin, and Liaoning has the lowest TFEE. Eventually, some policy suggestions are proposed for the influences of energy efficiency and study results. [ABSTRACT FROM AUTHOR]

Introduction: The transport of full containers and repositioning of empty containers are essential for the operation of a container logistic enterprise. In a large inland region, railway and road transportation take their own advantages for container transportation in terms of transport efficiency and costs. The combination of the two modes creates larger possibility for logistic enterprise to provide efficient service and reduce operation costs. Thus, this paper aims to optimize the inland intermodal transportation of full and empty containers.Methods: Different from cost minimum model, an integer programming model is proposed based on revenue management, making the model more reasonable in practice where logistic enterprises have the right to reject transportation demands from customers considering transport profits and capacity limitations. The real cases of transportation networks of Northeast China and parts of the southern Europe are applied to evaluate and describe the model and performance.Results: The results indicate that the proposed intermodal transportation optimization for both full and empty containers is feasible and profitable for logistic enterprises. The efficiency of container usage increases since we take the conversion of containers during transportation into account. Results also imply an inappropriate pricing strategy at certain inland depots in the case.Conclusions: This paper provides an optimization method for the intermodal transportation of full and empty containers in harbor-inland regions / hinterlands. Different from cost minimization in the literature, this paper models the transportation problem based on revenue management. That is, the model aims to maximize profits of logistic enterprise with the specific constraints in container transportation, as well as demand rejection. The model is proofed to be feasible in the real transportation networks and can create more profits for transportation enterprises. The analysis of real cases show that the total profits can be enlarged by considering the conversion of containers during transportation. In addition, it is verified that the optimization of inland transportation of empty and full containers reduces the operating costs of logistic enterprises. Moreover, results uncover the fact that a governed pricing policy at Suifenhe is not reasonable and may deteriorate the future export environment there. For the case based on part of southern Europe, it seems that the port, customer, inland transport operator and possibly container shipping company in Europe may benefit by establishing appropriate inland depots. [ABSTRACT FROM AUTHOR]

This article discusses the continuity between cosmopolitan collaboration and wartime collaborationism from 1932–1941 by exploring the Chinese Maritime Customs Service (CMCS) and its international staff. The CMCS managed China's international trade and directed the custom houses in northern China before 1937, and in occupied China and free China from 1937–1941. The customs revenues generated by this international trade were pledged to service China's international obligations. This article argues that both Chinese and Japanese staff members' activities to maintain the status quo could be considered as wartime collaborationism from the perspectives of Japan, Manchukuo, and the Collaborationist and Chongqing governments, but all parties tolerated their activities until the outbreak of the Pacific War. The reason for this was that all parties benefitted from the CMCS's management of international trade and its implementation of international obligations which had existed since the mid-nineteenth century. This article situates wartime collaborationism within the long-existing institutional network that was welcomed as cosmopolitan collaboration in the prewar, wartime, and postwar periods, rather than treating it as a unique wartime setup and ideology. Such a view also illuminates the postwar exchange of personnel and cooperation among former enemies, which grew out of prewar collaboration and wartime collaborationism. [ABSTRACT FROM AUTHOR]

The evaluation of conservation effectiveness for wetland protected areas (WPAs) is essential to underpin knowledge-based conservation policies and funding decisions by government and managers. In this paper, the conservation effectiveness for 28 WPAs in Northeast China from 2000 to 2012 was quantitatively evaluated using landsat thematic mapper image data and a maximum entropy model (Maxent). The spatial distribution of conservation effectiveness and the influence of human activities on conservation effectiveness were determined by combining a landscape development intensity (LDI) index and spatial analysis in a geographical information system. The results showed that the natural wetland area of all WPAs in Northeast China declined by 11.5 % and the conservation effectiveness of most of these WPAs decreased between 2000 and 2012. A significant negative correlation between the LDI index and conservation effectiveness ( r = −0.824, p < 0.01) suggested that human activities were responsible for the low conservation effectiveness of WPAs. The WPAs with the high conservation effectiveness were mainly located in the Da-Xing'an and Xiao-Xing'an Mountains, where anthropogenic activities were limited. The reduction in the conservation effectiveness of WPAs in the Songnen and Sanjiang Plains, which showed the most degradation, was due to conversion of wetlands to croplands. This research offers an efficient and effective method to evaluate the conservation effectiveness of WPAs. The results of this study will inform future ecological conservation and management of WPAs in China. [ABSTRACT FROM AUTHOR]

Northeast China (NEC) is one of the major agricultural production areas in China, producing about 30% of China's total maize output. In the past five decades, maize yields in NEC increased rapidly. However, farmer yields still have potential to be increased. Therefore, it is important to quantify the impacts of agronomic factors, including soil physical properties, cultivar selections, and management practices on yield gaps of maize under the changing climate in NEC in order to provide reliable recommendations to narrow down the yield gaps. In this study, the Agricultural Production Systems Simulator (APSIM)-Maize model was used to separate the contributions of soil physical properties, cultivar selections, and management practices to maize yield gaps. The results indicate that approximately 5%, 12%, and 18% of potential yield loss of maize is attributable to soil physical properties, cultivar selection, and management practices. Simulation analyses showed that potential ascensions of yield of maize by improving soil physical properties PAY s, changing to cultivar with longer maturity PAY c, and improving management practices PAY m for the entire region were 0.6, 1.5, and 2.2 ton ha−1 or 9%, 23%, and 34% increases, respectively, in NEC. In addition, PAY c and PAY m varied considerably from location to location (0.4 to 2.2 and 0.9 to 4.5 ton ha−1 respectively), which may be associated with the spatial variation of growing season temperature and precipitation among climate zones in NEC. Therefore, changing to cultivars with longer growing season requirement and improving management practices are the top strategies for improving yield of maize in NEC, especially for the north and west areas. [ABSTRACT FROM AUTHOR]

In rural areas of northeast China, residents often use a traditional Chinese kang for domestic heating. However, this heating method is associated with an uncomfortable thermal environment and poor indoor air quality. Therefore, this paper proposes a glazed transpired collector (GTC) based solar wall system, as a solution. Similar to air conditioning systems, the GTC is able to generate various airflow settings, which is one creative concept of the proposed system. Experimental and numerical studies were conducted to investigate the space heating and indoor air-quality improving performance of the system. The experimental results show that the average indoor temperatures can be increased from 12.12 °C to 16.17–18.19 °C, relevant to the various operating modes. The return-air mode reduces the concentrations of CO, CO 2 , PM 2.5 , and PM 10 by 34.8%, 20.3%, 14.4%, and 11.6%, respectively. The reductions relevant to the mixture mode are 69.6%, 28.0%, 45.0%, and 41.6%, respectively, and those to the fresh-air mode are 73.9%, 42.7%, 56.2%, and 58.1%, respectively. By numerically simulating the distributions of indoor air temperature and the concentrations of CO, CO 2 , PM 2.5 , and PM 10 , the GTC-based solar wall system is able to enhance the uniformity of temperature distribution and dilute indoor pollutant concentrations. To conclude, a summary of the simple and easy operating manual of the solar wall system is presented in this paper. The solar wall system can solve the problem of unacceptable indoor thermal comfort and indoor environmental pollution in rural dwellings in cold climates. [ABSTRACT FROM AUTHOR]

As a main grain production area in China, Northeast China (NEC) is highly influenced by the higher warming trend than elsewhere in China or even the globe. As the warming trend goes on, scientific understanding of the changes of thermal conditions in NEC will be essential for taking agricultural adaptation measures. In this paper, the high-resolution (25 km) corrected outputs of PRECIS (Providing Regional Climates for Impacts Studies) under the Representative Concentration Pathway 4.5 (RCP4.5) scenario were used to analyze the changes of the agro-climatic thermal resources in NEC. Results showed that accumulated temperature ≥10 °C (AT10) could increase by 300–500 °C·day, 500–900 °C·day, and 750–1000 °C·day in 2011–2040 (2020s), 2041–2070 (2050s), and 2071–2100 (2080s), respectively, relative to the baseline period of 1961–1990. The potential growing season (PGS) would then be prolonged by 11–19 days, 23–35 days, and 25–37 days in 2020s, 2050s and 2080s, respectively, compared to baseline. The spatial features for the changes of thermal indices would show a large increase of AT10 and an extension of PGS and Frost-free period (FFP) in mountainous areas compared to plains; the increment of AT10 would be greater in southern NEC than that in the north, with over 1000 °C·day in the southern parts and 700–800 °C·day in the northern parts in the 2080s. Additionally, the three thermal indices would increase rapidly from 2020s to 2050s compared to the period from 2050s to the 2080s, coincides with the greenhouse gas concentrations peak around the mid-period of the 21st century, and the decline towards the end of the 21st century under RCP4.5 forcing. The results of this paper could act as a guide to taking advantage of increasing thermal resources in NEC, and would be helpful for local practitioners in decision-making. [ABSTRACT FROM AUTHOR]

• This paper proposes to optimize the resource allocation of the food and energy waterl;. • Deepen the reform of the supply side of agriculture to alleviate the stress on water resources;. • The contradiction of water shortage will become more prominent in Northeast China. The production and consumption of grain and energy need physical water resources which causes the virtual water circulation. The recycling of water requires energy, and the food production is associated with the consumption of biomass energy, which competes with the energy production for water. This paper uses the water footprint of food production and Water pressure index corrected to calculate Production and transfer of food and energy in Northeast China. The results show that the energy water footprint of the Northeast region was 4.3 × 108 m3 In 2000, it reached a maximum value of 4.39×108 m3 in 2012, and whereafter the energy water footprint fell to only 3.73×108 m3 in 2015. In Northeast China, more water is embedded in the outflow of food and in the inflow of energy. In 2000, the energy water footprint outflow was 1.54×108 m3, and the energy water footprint inflow in 2015 reached 1.89×108 m3. With the expansion of the food and energy production in Northeast China, water resources stress continues to rise. Except for Liaoning Province, the water resources pressure indices of Heilongjiang Province and Jilin Province are much higher than the national average. [ABSTRACT FROM AUTHOR]

Inactive ice wedges are still present today at Yituli'he in the middle Da Xing'anling (Greater Hinggan) Mountains in northeastern China, which is the southernmost known site (50°37′N) with ice wedges in the Northern Hemisphere. However, it is uncertain whether the ice-wedge isotope composition, characterized by low δ18O, δD and low deuterium excess values, is representative of the isotope signature of a broader region. In this paper, the ice-wedge isotope compositions were examined in the context of the stable isotopes of precipitation from the nearby Global Network of Isotopes in Precipitation ( GNIP) stations. In addition, the pollen spectra from the host sediments were analysed to provide additional information on local vegetation in order to better understand the climate conditions favouring ice-wedge formation. The pollen spectra suggest that the Yituli'he ice wedges developed during the colder and wetter period after 6000 cal. a BP. The isotopes in the Yituli'he ice wedges are consistent with the isotope background recorded in atmospheric precipitation collected at the nearby GNIP stations. When the snow-melt froze into ice veinlets, the isotope signals did not change substantially because of the strong, cold, continental anticyclones in winter as well as a strong temperature inversion that prevail in the Da Xing'anling Mountains. As the climate pattern did not change substantially, the neoglacial cold period is unlikely to have allowed for strong secondary fractionation of isotope records during ice-wedge formation. Thus, the annual isotope signature can be interpreted as a valid archive of climate data. [ABSTRACT FROM AUTHOR]

Zircon U-Pb ages, Hf isotope data and whole-rock major and trace element data for the Middle to Late Ordovician gabbros and granites in the Erguna Massif, NE China were presented in this paper. The petrogenesis of these rocks and the Early Paleozoic tectonic evolution of the massif were discussed. Zircons from the granites and gabbros are of magmatic origin based on their cathodoluminescence (CL) images. The Pb/U ages obtained from 20 spots on zircons from the granites range from 446±9 to 464±10 Ma, yielding a weighted mean age of 455±10 Ma; and 16 spots on zircons from the gabbros range from 465±10 to 466±7 Ma, yielding a weighted mean age of 465±2 Ma. Chemically, the Late Ordovician granites in the Erguna Massif are weakly peraluminous and similar to A-type granites. The granites and gabbros are all enriched in light rare earth elements and large ion lithophile elements (e.g., Rb, K), and depleted in heavy rare earth elements and high field strength elements (e.g., Nb, Ta, and Ti); they all exhibit marked negative Eu anomalies. Their zircon ɛ( t) values range mainly from +1.86 to +6.21 (for the granites) and +1.39 to +3.89 (for the gabbros), except for one spot with a value of −0.27 (for a gabbro). The T ages for the gabbros and T ages for the granites vary from 928 to 1 091 Ma and from 1 287 to 1 675 Ma, respectively. It is concluded that the primary magma of the granites could have been derived by partial melting of Mesoproterozoic newly accreted crustal material, whereas the primary magma of the gabbros originated by partial melting of a depleted mantle wedge that had been metasomatized by fluids derived from a subducted slab. These Middle-Late Ordovician granites and gabbros constitute a typical bimodal igneous rock association, implying an extensional environment that was probably related to the post-collisional development of the Erguna and Xing'an massifs in the early Early Paleozoic. [ABSTRACT FROM AUTHOR]

Extreme climate events frequently exert serious effects on terrestrial vegetation activity. However, these effects are still uncertain in widely distributed areas with different climate zones. Transect analysis is important to understand how terrestrial vegetation responds to climate change, especially extreme climate events, by substituting space for time. In this paper, seven extreme climate indices and the Normalized Difference Vegetation Index (NDVI) are employed to examine changes in the extreme climate events and vegetation activity. To reduce the uncertainty of the NDVI, two satellite-derived NDVI datasets, including the third generation Global Inventory Monitoring and Modeling System (GIMMS-3g) NDVI dataset and the NDVI from the National Oceanic and Atmospheric Administration (NOAA) satellites on Star Web Servers (SWS), were employed to capture changes in vegetation activity. The impacts of climate extremes on vegetation activity were then assessed over the period of 1982–2012 using the North–South Transect of Eastern China (NSTEC) as a case. The results show that vegetation activity was overall strengthened from 1982 to 2012 in the NSTEC. In addition, extreme high temperature events revealed an increased trend of approximately 5.15 days per decade, while a weakened trend (not significant) was found in extreme cold temperature events. The strengthened vegetation activities could be associated with enhanced extreme high temperature events and weakened extreme cold temperature events over the past decades in most of the NSTEC. Despite this, inversed changes were also found locally between vegetation activity and extreme climate events (e.g., in the Northeast Plain). These phenomena could be associated with differences in vegetation type, human activity, as well as the combined effects of the frequency and intensity of extreme climate events. This study highlights the importance of accounting for the vital roles of extreme climate effects on vegetation activity. [ABSTRACT FROM AUTHOR]

Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease (CAD). However, there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes, especially in cold regions. This study aimed to systematically investigate the relationship between exposure to meteorological changes, air pollutants, and hospitalization for CAD in cold regions. We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1, 2009, and December 31, 2019. Poisson regression analysis, based on generalized additive models, was applied to estimating the influence of hospitalization for CAD. Significant associations were found between low ambient temperature [-10°C, RR = 1.65; 95% CI: (1.28–2.13)] and the incidence of hospitalization for CAD within a lag of 0–14 days. Furthermore, O3 [95.50 μg/m3, RR = 12; 95% CI: (1.03–1.21)] and NO2 [48.70 μg/m3, RR = 1.0895% CI: (1.01–1.15)] levels were identified as primary air pollutants affecting the incidence of CAD, ST-segment-elevation myocardial infarction (STEMI), and non-STEMI (NSTEMI) within the same lag period. Furthermore, O3 [95.50 μg/m3, RR = 1.12; 95% CI: (1.03–1.21)] and NO2 [48.70 μg/m3, RR = 1.0895% CI: (1.01–1.15)] levels were identified as primary air pollutants affecting the incidence of CAD, ST-segment-elevation myocardial infarction (STEMI), and non-STEMI (NSTEMI) within the same lag period. The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO2 and O3 concentrations were higher, with a pronounced effect at 7 days, dissipating by lag 14 days. No significant associations were observed between exposure to PM, SO2, air pressure, humidity, or wind speed and hospitalization incidences due to CAD and its subtypes. Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants (O3 and NO2) and hospitalizations for CAD, STEMI, and NSTEMI. These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events. [ABSTRACT FROM AUTHOR]

This article examines the 1901–1904 discussions about free trade in the Priamur region and the territories in Chinese Manchuria leased to the Russian Empire. The discussions are placed in the contexts of nationalising empire, Russian imperialism, and cosmopolitan society of the globalised free port of Vladivostok. The piece traces the place of ideas about free trade in the social and political imagination of contemporaries in the Priamur region to show how these images were challenged by imperial expansion in Manchuria. It also analyses the rhetorical strategies used by regional actors to re-negotiate the borders of economic and political expansion, as well as the internal and external comparisons they made. The article demonstrates how debates about free trade in the Russian Far East offer deeper insight into how ideas about free trade and free ports as institutions affected not only the economic but social and political transformations in the late imperial period. [ABSTRACT FROM AUTHOR]

Korean pine (Pinus koraiensis Sieb. et Zucc.) is one of the highly commercial woody species in Northeast China. In this study, six nonlinear equations and artificial neural network (ANN) models were employed to model and validate height-diameter (H-DBH) relationship in three different stand densities of one Korean pine plantation. Data were collected in 12 plots in a 43-year-old even-aged stand of P. koraiensis in Mengjiagang Forest Farm, China. The data were randomly split into two datasets for model development (9 plots) and for model validation (3 plots). All candidate models showed a good perfomance in explaining H-DBH relationship with error estimation of tree height ranging from 0.61 to 1.52 m. Especially, ANN models could reduce the root mean square error (RMSE) by the highest 40%, compared with Power function for the density level of 600 trees. In general, our results showed that ANN models were superior to other six nonlinear models. The H-DBH relationship appeared to differ between stand density levels, thus it is necessary to establish H-DBH models for specific stand densities to provide more accurate estimation of tree height. [ABSTRACT FROM AUTHOR]

Abstract The soil organic carbon (SOC) and total nitrogen (TN) of topsoil could be greatly affected by the conversion of grassland to cropland (CGC) due to vegetation harvesting and soil erosion. However, few studies have evaluated the effects of these changes in the subsoil and distinguished its main controls at the regional scale. This paper investigated the total changes in the SOC stock (SOC S) and TN stock (TN S) of soils from 0 to 30 cm and 0–100 cm in depth over the past three decades in the Songnen Plain, China, a typical Mollisol region. The CGC resulted in a moderate loss of topsoil C and N but an increase in subsoil C and N, and the soil mapping results showed that approximately 7.47 × 1011 kg C and 1.51 × 1011 kg N were accumulated during the past three decades. Prediction uncertainty was assessed by 100 model runs with random jackknife partitions, and high uncertainty was found in the areas with rapidly changing SOC S and TN S levels. Our findings indicated that subsoil should be considered in the estimation of the SOC S and TN S at the regional scale. The SOC S and TN S of the CGC areas were anticipated to increase after long-term cultivation. In view of ongoing cropland expansion, up-to-date land use and soil type data are vital for selecting monitoring sites and understanding long-term soil evolution at the regional scale. Highlights • Conversion of grassland to cropland led to a moderate loss of topsoil C and N, but an increase in C and N in subsoil. • Subsoil should be considered for the estimation of SOC and TN stocks at the regional scale. • The SOC and TN stocks of recent cultivated soils were anticipated to increase after a long term cultivation. [ABSTRACT FROM AUTHOR]

Globally, natural wetlands have suffered severe ecological degradation (vegetation, soil, and biotic community) due to multiple factors. Understanding the spatiotemporal dynamics and driving forces of natural wetlands is the key to natural wetlands' protection and regional restoration. In this study, we first investigated the spatiotemporal evolutionary trends and shifting characteristics of natural wetlands in the Northeast Plain of China from 1990 to 2020. A dataset of driving-force evaluation indicators was constructed with nine indirect (elevation, temperature, road network, etc.) and four direct influencing factors (dryland, paddy field, woodland, grassland). Finally, we built the driving force analysis model of natural wetlands changes to quantitatively refine the contribution of different driving factors for natural wetlands' dynamic change by introducing the sparrow search algorithm (SSA) and extreme gradient boosting algorithm (XGBoost). The results showed that the total area of natural wetlands in the Northeast Plain of China increased by 32% from 1990 to 2020, mainly showing a first decline and then an increasing trend. Combined with the results of transfer intensity, we found that the substantial turn-out phenomenon of natural wetlands occurred in 2000–2005 and was mainly concentrated in the central and eastern parts of the Northeast Plain, while the substantial turn-in phenomenon of 2005–2010 was mainly located in the northeast of the study area. Compared with a traditional regression model, the SSA-XGBoost model not only weakened the multicollinearity of each driver but also significantly improved the generalization ability and interpretability of the model. The coefficient of determination (R2) of the SSA-XGBoost model exceeded 0.6 in both the natural wetland decline and rise cycles, which could effectively quantify the contribution of each driving factor. From the results of the model calculations, agricultural activities consisting of dryland and paddy fields during the entire cycle of natural wetland change were the main driving factors, with relative contributions of 18.59% and 15.40%, respectively. Both meteorological (temperature, precipitation) and topographic factors (elevation, slope) had a driving role in the spatiotemporal variation of natural wetlands. The gross domestic product (GDP) had the lowest contribution to natural wetlands' variation. This study provides a new method of quantitative analysis based on machine learning theory for determining the causes of natural wetland changes; it can be applied to large spatial scale areas, which is essential for a rapid monitoring of natural wetlands' resources and an accurate decision-making on the ecological environment's security. [ABSTRACT FROM AUTHOR]

During the initial period of straw return, a suitable straw return technology can lay the foundation for long-term soil fertility improvement. This study focused on the issues of backward straw return technology and blind fertilizer application in the southern part of the maize-producing area in the Northeast Plain of China. In this study, two straw return modes (2-year no-tillage straw cover + 1-year deep loosening and burying straw returning mode, NPT; 3-year rotary tillage and burying straw returning mode, RT), with RT mode as a control, were combined with different N fertilizer application rates (0, 192, 240 kg/ha). The changes in soil organic carbon (SOC) and its active components (MBC, DOC, and LOC) in the 0–40 cm soil layer were analyzed, and the carbon stratification rate, carbon pool index (CPI), SOC storages of each component, and maize yield were calculated to evaluate the short-term (3-year) differences in soil organic carbon quantity and quality in order to find suitable straw return methods and nitrogen application rate combinations. The results showed that the NPT mode increased the SOC and MBC content in the 20–30 cm soil layer, with an increase of 16.2% to 37.8% and 23.0% to 50.3%, respectively, compared with the RT mode. Under the NPT mode, the carbon pool stability was higher after nitrogen fertilizer addition, with a CPI value of 10.2% to 37.8% higher in the 20–40 cm soil layer compared with the RT mode. The differences in maize yield were not significant (p < 0.05) between the nitrogen application rates of 192 kg/ha and 240 kg/ha, but the SOC storages did not show significant changes. The MBC storage had the highest value under the nitrogen application rate of 192 kg/ha. Therefore, we thought that, in the early stage of straw return, the organic carbon priming effect caused by increased microbial activity was higher under the nitrogen application rate of 192 kg/ha. Considering the aspects of not affecting maize yield and improving SOC stability, it is recommended to use the NPT mode with the application of a 240 kg/ha nitrogen fertilizer rate for straw return. [ABSTRACT FROM AUTHOR]

Straw bale buildings have the potential reduce the environmental impact of construction. Although the technique has been introduced into northern China more than a decade ago, the construction method and potential problems within straw bale walls have not been fully understood in existing research. Following an analysis of existing straw bale construction both in north China and worldwide, this paper proposes modifications to the straw bale construction details currently used in north China. The modifications involve in-fill raw material, toe-up design and lime render application. These modifications were incorporated into an experimental building constructed in north China, and after having been monitored for 12 months, the modified construction details were critically assessed. The data demonstrate that rice straw bale walls are resistant to agents of decay and offer reduced construction time and cost than standard wall construction in north China. The construction method has the potential to become a mature construction system in the Chinese market in the future offering significant benefits both in construction and operational cost and in environmental impact. [ABSTRACT FROM AUTHOR]

The space P and space L representation models are often adopted together in the empirical analysis of bus transport networks (BTNs). In this paper, we develop a new representation model for BTNs using double edge weights and node weights, namely perfect space P. The model incorporates the number and lengths of directed routes between the two stations and the number of routes that connect to each station. Based on the model, we develop an empirical study on four large BTNs in Northeast China. Some common network characteristics of the BTNs are revealed and discussed in detail. The results show that several empirical distributions follow an exponential law. Moreover, the unweighted path length distributions can be fitted by a Gaussian function, while the weighted path length distributions can be fitted by a composite Gaussian function. Specifically, we introduce the weighted-degree distribution with different lengths and the special edge weight distribution, given the new evidence for the random behavior during the expansion of BTNs, including new stations and routes. [ABSTRACT FROM AUTHOR]