Progress in China’s climate change study in the 20th century

IPCC (2001) pointed out that the earth's climate was undergoing a remarkable change with characteristics of global warming over the past 100 years. The latest research showed that the global mean surface temperature has increased by about 0.6 oC since 1861. It is very likely that the last 20 years in the 20th century was the warmest decades. The Northern Hemisphere temperatures in the 20th century appeared to have been unprecedented during the past millennium. The research also indicates th…     

Progress of economic geography in China’s mainland since 2000

Economic geography in China’s mainland has developed in a different way from that in many other countries. On the one hand, it has been increasingly active in participating in academic dialogues and knowledge development led by Anglophone countries; on the other hand, it takes practice-based and policy-oriented research, i.e. satisfying the demands from the Chinese government and society, as the linchpin of research. Since there has been a lot of literature reviewing the development of economic geography in the country before the new millennium, this paper will make a comprehensive analysis of the discipline in 2000–2015, based on a bibliometric survey and research projects done by Chinese economic geographers. The analysis indicates that (1) economic geography research in China’s mainland is unevenly distributed but concentrated in several leading institutions; (2) traditional research fields like human-nature system, regional disparity, industrial location and transportation geography remain dominant while new topics such as globalization, multinational corporations and foreign direct investments, information and communication technology, producer services, climate change and carbon emission emerge as important research areas; (3) Chinese economic geography is featured by policy-oriented research funded by government agencies, having considerable impacts on regional policy making in China, both national and regional. To conclude, the paper argues that the development of economic geography in China’s mainland needs to follow a dual track in the future, i.e. producing knowledge for the international academic community and undertaking policy-oriented research to enhance its role as a major consulting body for national, regional and local development.     

An empirical study of the registered population transformation in China’s megacities

From 2020 to 2030, accelerating the “citizenization” of the migrant population is key to promoting urbanization and achieving common prosperity. The urbanization rate of the registered population in China is roughly 18% lower than that of permanent residents. The pressure of the ageing population and the lack of a labor force have caused big cities to introduce relevant policies to attract talent, and the citizenization process needs to be improved urgently, with a particular focus on megacities. The transformation in the number of registered residents in megacities varies greatly, and there is a lack of research on this topic, which makes it an important academic issue. Using both natural and social perspectives, we selected concise indicators and combined the possibility-satisfiability model to estimate the urbanization transformation gap of annual household registration. Further, we constructed a panel data model to empirically analyze the different factors leading to the gap of household registration in megacities. The main factors affecting the transformation of the registered population in megacities are medical services, as well as educational resources and the urban water supply. It is urgent for urban and rural administrators to change the current passive and rigid institutional mechanisms and to ensure flexible, normal governance.     

Landscape pattern dynamics of water body in Kaifeng city in the 20th century

Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape pattern has been one of the key study areas. Water body landscape plays an important role in the development history of a city, but at present city water body landscape in many cities has been destroyed, hence protecting water body in the city is becoming more and more important. In order to protect city water body landscape reasonably, the precondition is to probe the dynamics of water body landscape. Based on historical data and remote sensing data, six indexes including patch number, patch area, landscape dominance index, fractal dimension, patch density and connectivity index etc. were used to analyze landscape pattern dynamics of water body in Kaifeng city since the end of the Qing Dynasty (in the 20th century). The results showed: (1) Since the end of the Qing Dynasty, landscape area of water body in Kaifeng city increased first and then decreased from 1898 to 2002AD; the landscape dominant degree had the same changing tendency with the area. (2) Patch number of water body landscape in Kaifeng city had an increase from 1898 to 2002, but maximum area of patch, minimum area of patch and average area of patch decreased, which resulted in an increase in landscape fragment degree. (3) Connectivity index decreased and fractal dimension increased from 1898 to 2002. The reasons for these changes were the repeated overflows and flooding of the Yellow River and the influence of human activities.     

Progress in China’s sustainable development research: Contribution of Chinese geographers

Sustainable development has always been a hotspot in Chinese geographical research. Herein, we conduct a systematic statistical analysis of the contribution of Chinese geographers to sustainable development research using bibliometric methods. Based on the review of a vast amount of literature, we identify the main research teams, research funding sources, journals, and key research fields. The findings are as follows: (1) the resources and environmental institutes of the Chinese Academy of Sciences have a significant influence on sustainable development research; (2) China’s central government foundations (the National Natural Science Foundation of China and National Social Sciences Fund) are the main research funding sources; (3) most of the highly cited articles are published in journals sponsored by the Geographical Society of China; and (4) sustainable development theory and its research areas are being constantly enriched and perfected. Based on the statistics of keywords, the theory, research methods, research regional scales, and key research areas are summarized and expounded.     

Response of diatom community in Lugu Lake (Yunnan–Guizhou Plateau,China) to climate change over the past century

A mean annual temperature increase has been recorded on the Yunnan–Guizhou Plateau of China during the last century. This temperature increase has been significantly greater since the 1950s. Thus, paleolimnological analyses may be utilized to better understand ecological responses to recent changing climate over decadal to centennial timescales, especially in regions with sparse lake monitoring data. Here, we present paleolimnological results from a ²¹⁰Pb/¹³⁷Cs-dated sediment core spanning approximately the last ~250 years from a remote, alpine, semi-closed oligotrophic lake (Lugu Lake) on the northwestern Yunnan–Guizhou Plateau. Sediment profiles of diatoms, geochemical variables (LOI₅₅₀, TOC and C/N) and median grain size were analyzed and compared with the climate data (1951 AD–2010 AD) from the Lijiang weather station. Endogenous productivity of Lugu Lake has increased gradually over the last 30 years. The majority of diatom taxa encountered in the core are typical of alkaline oligotrophic lakes. Diatom assemblages were dominated by Cyclostephanos dubius, Cyclotella taxa, and fragilarioid taxa. Diatom species composition has changed significantly with three assemblage shifts at different scales over the ~250-year period. Diatom species diversity reveals a distinct increase before ~1970 AD, followed by a decline. In addition, a decreasing trend in diatom cell-size was consistent with recent warming trends. Redundancy analysis (RDA) shows that regional air temperature trends (annual, spring, summer, and winter) have played a significant role (p < 0.05) in determining diatom compositional changes over the past six decades. Results of this study suggest that regional warming is the main driving force behind recent changes in diatom composition at Lugu Lake, while nutrients may also have impact on the diatom change in recent 10 years.     

A study of provincial differences in China’s eco-compensation framework

In this study, we developed a theoretical framework to analyze the provincial differences in eco-compensation and selected appropriate measurement methods to investigate these differences in the operation of the eco-compensation framework. Via the use of the coefficient of variation, Atkinson index, and Gini coefficient, we investigated the overall differences in Chinese provincial eco-compensation time series data from 2004 to 2014 and studied the driving mechanism underlying these differences. The results showed that: (1) The provincial eco-compensation standard has geographical features. For example, the provinces crossed by the “HU Huanyong Line”, or located to its northwestern side, have obtained extensive eco-compensation. (2) There was a trend for differences in eco-compensation to increase over time, but with some fluctuations in 2006, 2009, and 2014 as shown by the coefficient of variation, in 2005, 2007, 2011, 2013, and 2014 as shown by the Gini coefficient, and in 2007, 2008, 2011, and 2012 as shown by the Atkinson index. (3) Time series curves indicated that while the signals from the three metrics (coefficient of variation, Atkinson index, and Gini coefficient) differ in a short-term analysis, they show the same tendency in the longer term. The results indicate that it is necessary to evaluate the differences in eco-compensation at the provincial level over a long period of time. (4) Via the calculation of the virtual Gini coefficient, we found that among the factors that influence provincial differences in eco-compensation, the economic value of eco-resources played the decisive role, explaining more than 73% of the difference. The cost of environmental pollution abatement was the second most important factor, accounting for more than 19% of the difference. The input to environmental pollution abatement had the least influence, accounting for less than 8% of the difference. The results agreed with those obtained from other studies, and could be used as a reference by policy makers.     

Whose climate change adaptation ‘barriers’? Exploring the coloniality of climate change adaptation policy assemblages in Thailand and beyond

Climate change adaptation (CCA) ‘barriers’ are frequently seen as responses to biophysical climate impacts, and thus defined as ‘obstacles’ to be ‘overcome’, rendered into categories of the techno-managerial. However, barriers are often undertheorized and are blind to explanations of their origins or the causal mechanisms by which they operate. This is especially complex for barrier critiques in the Global South in particular. Using a ‘hybrid’ assemblage and postcolonial approach, this paper disentangles existing barrier critiques in Thailand to lay bare underlying power imbalances and tensions. It finds that ‘simplistic’ vulnerability framings have deep roots in postcolonial histories; ‘complacent’ mainstreaming/budgeting trajectories have been nurtured by various IOs, and not necessarily much-maligned Thai bureaucrats; and limited technical expertise/willingness to engage are not so illogical, but rather results of diverse external forces. Given this, this paper urges institutional actors and researchers to reflect on epistemology, ontology, and their own positionality when assessing barriers in future.     

Impacts of climate change in Central Planins of China： on winter wheat yield Case study of Shangqiu

为探明气候变化对商丘地区冬小麦产量的影响,根据1991～2010商丘市气候资料和小麦产量资料,利用数学统计与Thornthwaite Memoriae模型,结合未来气候预测结果定量分析了气候变化对冬小麦产量的影响。结果表明,冬小麦产量整体上呈波动上升趋势;主成分分析表明,气温、降水量、蒸发量与极端温度为影响冬小麦产量的主要气候因子,蒸发量过大及极端低温对冬小麦生产不利。商丘地区“暖湿型”气候有利于冬小麦生产力的提高,“冷干型”气候对冬小麦生产最为不利;未来几十年内气候可能将向“暖湿型”变化,对商丘地区粮食作物产量的提升较为有利。     

The effect of environmental factors on spatial variability in land use change in the high-sediment region of China’s Loess Plateau

In areas with topographic heterogeneity, land use change is spatially variable and influenced by climate, soil properties, and topography. To better understand this variability in the high-sediment region of the Loess Plateau in which soil loss is most severe and sediment diameter is larger than in other regions of the plateau, this study builds some indicators to identify the characteristics of land use change and then analyze the spatial variability as it is affected by climate, soil property, and topography. We build two indicators, a land use change intensity index and a vegetation change index, to characterize the intensity of land use change, and the degree of vegetation restoration, respectively. Based on a subsection mean method, the two indicators are then used to assess the spatial variability of land use change affected by climatic, edaphic, and topographic elements. The results indicate that： 1） Land use changed significantly in the period 1998-2010. The total area experiencing land use change was 42,302 km2, accounting for 22.57%of the study area. High-coverage grassland, other woodland, and forest increased significantly, while low-coverage grassland and farmland decreased in 2010 compared with 1998.2） Land use change occurred primarily west of the Yellow River, between 35 and 38 degrees north latitude. The four transformation types, including （a） low-coverage grassland to medium-coverage grassland, （b） medium-coverage grassland to high-coverage grassland, （c） farmland to other woodland, and （d） farmland to medium-coverage grassland, were the primary types of land use change, together constituting 60% of the area experiencing land use change. 3） The spatial variability of land use change was significantly affected by properties of dryness/wetness, soil conditions and slope gradient. In general, land use changed dramatically in semi-arid regions, remained relatively stable in arid regions, changed significantly in clay-rich soil, remained relatively stable in clay-poor soil, changed dramatically in steeper slopes, and remained relatively stable in tablelands and low-lying regions. The increase in vegetation coincided with increasing changes in land use for each physical element. These findings allow for an evaluation of the effect of the Grain to Green Program, and are applicable to the design of soil and water conservation projects on the Loess Plateau of China.     

Relative soil moisture in China’s farmland

Journal of Geographical Sciences - Based on the data of relative soil moisture in 653 agricultural meteorological stations during the period of 1993‒2013 in China, the characteristics and...     

Spatial distribution of maize in response to climate change in northeast China during 1980–2010

Based on county-level crop statistics and other ancillary information, spatial distribution of maize in the major maize-growing areas (latitudes 39°–48°N) was modelled for the period 1980–2010 by using a cross-entropy-based spatial allocation model. Maize extended as far north as the northern part of the Lesser Khingan Mountains during the period, and the area sown to maize increased by about 5 million ha. More than half of the increase occurred before 2000, and more than 80% of it in the climate transitional zone, where the annual accumulated temperature (AAT) was 2800–3400 °C·d. Regions with AAT of 3800–4000 °C·d became more important, accounting for more than 25% of the increase after 2000. The expansion of maize was thus closely related to warming, although some variation in the distribution was noticed across zones in relation to the warming, indicating that maize in northeast China may have adapted successfully to the warming by adjusting its spatial distribution to match the changed climate.     

Progress in sandy desertification research of China

Desertification is one of the most serious environmental and socio-economic problems facing the world today. Because the rapid expansion of desertification has resulted in serious environmental deterioration, economic loss, locally unsteadiness political situation and social upheaval, it has become a hot-spot issue of worldwide concern. During the late 1960s and early 1970s, as the catastrophic drought in the west Africa greatly accelerated the development of desertification, the desertificati…     

Embodied land in China’s provinces from the perspective of regional trade

With the continuous enhancement of regional connectivity, the indirect use of land resources through the pathways of trade in goods and services plays an increasingly important role in the overall utilization of land resources. Despite this, relevant research in this field is still in its infancy, and few papers have addressed this issue. This paper uses a multi-regional input-output model to calculate the embodied land in the 30 provinces (autonomous regions and municipalities) and eight regions of China from the perspective of regional trade and further analyzes the spatial pattern of characteristics associated with embodied land flows. The results show that the amount of embodied land occupied by China’s inter-regional trade accounts for 21.39% of the country’s total land, and an average of 38.54% of China’s provincial land demand is met by land exports from other provinces. More than 80% of land consumed by Beijing, Tianjin, and Shanghai is from other provinces. The provinces of Heilongjiang, Inner Mongolia, Xinjiang, and Hebei are the largest net exporters of cultivated land, forest and grazing and aquatic land, fishery land, and built-up land, respectively (the outflows account for 42.26%, 27.53%, 38.66%, and 35.28% of the corresponding land types in the province); and Guangdong, Shandong, and Zhejiang are the main net importers. The flow of agricultural land (cultivated land, forest land, grazing land, and aquatic land) generally shows a shift from west to east and from north to south. The regions in northeast and northwest China have the largest scale of agricultural land outflows, mainly into East and South China. In addition, 8.43% of cultivated land, 7.47% of forest land, 6.41% of grazing land, 6.88% of aquatic land, and 18.35% of built-up land in China are provided for foreign use through international trade. This paper provides feasible ideas and a theoretical basis for solving the contradiction between land use and ecological protection, which could potentially help to achieve sustainable land use in China.     

Have China’s drylands become wetting in the past 50 years?

Recently, whether drylands of Northwest China (NW) have become wetting has been attracting surging attentions. By comparing the Standard Precipitation Evapotranspiration Indices (SPEI) derived from two different potential evapotranspiration estimates, i.e., the Thornthwaite algorithm (SPEI_th) and the Penman-Monteith equation (SPEI_pm), we try to resolve the controversy. The analysis indicated that air temperature has been warming significantly at a rate of 0.4°C decade^?1 in the last five decades and the more arid areas are more prone to becoming warmer. Annual precipitation of the entire study area increased insignificantly by 3.6 mm decade^?1 from 1970 to 2019 but NW presented significantly increasing trends. Further, the SPEI_th and SPEI_pm demonstrated similar wetting-drying-wetting trends (three phases) in China’s drylands during 1970-2019. The common periodical signals in the middle phase were identified both by SPEI_th and SPEI_pm wavelet analysis. Analysis with different temporal intervals can lead to divergent or even opposite results. The attribution analysis revealed that precipitation is the main climatic factor driving the drought trend transition. This study hints that the wetting trend’s direction and magnitude hinge on the targeted temporal periods and regions.     

Whose knowledge matters in climate change adaptation? Perceived and measured rainfall trends during the last half century in south‐western Tanzania

Parts of eastern Africa have experienced substantial climatic variability and extremes during the last few decades. Here we explore the extent to which local place‐based knowledge is used and is relevant to understanding and appropriately responding to place‐based climate variability and change (specifically rainfall) in an area of considerable rainfall variability in south‐western Tanzania. Primary data were collected using focus group discussions and household questionnaire surveys, and secondary data obtained from government institutions. Various changes associated with the frequency, intensity and consistency of rainfall during the period 1960 to 2014 are explored. Findings indicate that knowledge and perceptions associated with climate operate at a local level, and that these are not necessarily applicable to neighbouring regions. Smallholder farmers in the Great Ruaha River Sub‐Basin rely on incremental adaptations of agricultural practices, in response to climatic stresses which have long‐term implications. We argue that incremental adaptations ought to be supplemented by more transformative changes of existing agricultural practices, such as using more climate‐adapted crops and livestock. Moreover, caution is required when examining human perceptions and responses to climate variability and change at the site‐specific scale, as such findings may not necessarily be applicable to broader regions in all cases.     

The impacts of climate change on hydrology in a typical glacier region—A case study in Hailuo Creek watershed of Mt. Gongga in China

The glaciers of the Hengduan Mountains play an important role in the hydrology processes of this region. In this study, the HBV Light model, which relies on a degree-day model to simulate glacier melting, was employed to simulate both glacier runoff and total runoff. The daily temperature and precipitation at the Hailuo Creek No. 1 Glacier from 1952 to 2009 were obtained from daily meteorological observed data at the glacier and from six national meteorological stations near the Hailuo Creek Basin. The daily air temperature, precipitation, runoff depth, and monthly potential evaporation in 1995, 1996, and 2002 were used to obtain a set of optimal parameters, and the annual total runoff and glacier runoff of the Hailuo Creek Glacier(1952–2009) were calculated using the HBV Light model. Results showed the average annual runoff in the Hailuo Creek Basin was 2,114 mm from 1952 to 2009, of which glacial melting accounted for about 1,078 mm. The river runoff in the Hailuo Creek catchment increased as a result of increased glacier runoff. Glacier runoff accounted for 51.1% of the Hailuo Creek stream flow in 1994 and increased to 72.6% in 2006. About 95% of the increased stream flow derived from the increased glacier runoff.     

Bargaining for nature: treating the environment in China’s urban planning practice

ABSTRACT

In much of the contemporary academic inquiry and political discourse on Chinese cities, urban entrepreneurialism and environmentalism often appear to be analyzed disjointedly and unreflectively. They are portrayed as two conflicting interests. Commentators also view urban planners as a homogenous group of professionals and/or state agents being forced to give up environmental goals to pursue economic value of space. Using the case of Tianjin Eco-City planning, this article interrogates the bargaining process between the “ecological value” and “commodity narrative”. It offers three major arguments. First, even though the discourse of environmental sustainability has been used to legitimize economic transformation, ecological demands are creating new pressures on entrepreneurial urban governance. Second, rather than treating Chinese planners as a fully constituted, internally coherent, organizationally-fixed, and operationally-consistent group, they should be viewed as hybrid, and diverse entities that represent divergent and sometimes contentious state interests. Third, planners, though still under tremendous pressure from landed interests, can become active players to positively influence urban transformation toward more environmental care.     

Modeling the impacts of climate change on China''s agriculture

1 Introduction Since recognition of the potential climate change [IPPC, 1990], efforts have been made to estimate the economic impacts of projected changes in climate on important sectors, such as agriculture, forestry and ecosystem, coastal zones and fisheries, water resource, and energy development. Although several sectors have been studied, none have received more attention than agriculture. Countrywide economic analysis has been completed for the United States[1-4], India[5] and Brazil…     

Multi-designated geoparks face challenges in China’s heritage conservation

The author selects a thorny issue of doubled designations that bother pol- icy-makers, professional planners and managers in the field of conservation for protected areas. The analyzed case study areas cover 5 National Geoparks of China in Sichuan Prov- ince, 18 UNESCO Global Geoparks in China, and 219 World Heritage sites in China and 8 European nations. Through analysis and synthesis, the author concludes that doubled des- ignation, which also leads to unbalanced park distribution, is particularly prevalent in China other than in Europe. Therefore, on-site management agencies and related governments in China should carefully translate the doubled designations into responsibilities and harmoni- ous partnerships between all stakeholders in order to enhance the management effectiveness and avoid paper park phenomenon.