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A spatially-explicit cropland distribution time-series dataset is the basis for the accurate assessment of biogeochemical processes in terrestrial ecosystems and their feedback to the climate system; however, this type of dataset is lacking in China. Existing cropland maps have a coarse resolution, are intermittently covered, or the data are inconsistent. We reconstructed a continuously covered cropland distribution dataset in China spanning from 1900 to 2016 by assimilating multiple data sources. In total, national cropland acreage expanded from 77.72 Mha in 1900 to the peak of 151.00 Mha in 1979, but it consistently decreased thereafter to 134.92 Mha in 2016. The cropland was primarily distributed in three historically cultivated plains in China: the Sichuan Plain, the Northern China Plain, and the Northeast China Plain. Cropland abandonment was approximately 29.90 Mha; it was mainly concentrated in the Northern China Plain and the Sichuan Plain and occurred during the 1990–2010 period. Cropland expansion was over 74.30 Mha; it was primarily found in the southeast, northern central, and northeast regions of China and occurred before 1950. In comparison, the national total and spatial-distribution of cropland in the Food and Agriculture Organization (FAO) of the United Nations and the History Database of the Global Environment (HYDE) were distorted during the period of 1960–1980 due to the biased signal from the Chinese Agricultural Yearbook. We advocate that newly reconstructed cropland data, in which the bias has been corrected, should be used as the updated data for regional and global assessments, such as greenhouse gas emission accountings and food production simulations. The cropland dataset is available via an open-data repository (https://doi.org/10.6084/m9.figshare.13356680) (Yu et al., 2020).

The widespread existence of lead (Pb) contamination in soil has received extensive attention. To effectively slow lead-ion (Pb2+) migration and promote plant growth in heavy metal-contaminated soil as well as to realize the resource utilization of solid waste, vermireactors were used to obtain vermicompost using cow dung mixed with modified mineral (MM) as feedstock material for Eisenia fetida. Vermicompost was characterized first, and then its slowing effect on Pb2+ migration in soil was further evaluated through pot experiments. The results demonstrated that earthworms could grow well in cow dung and mineral vermireactors, and earthworm activity increased the cation exchange capacity (CEC), total nutrient content and surface area but decreased the pH, carbon to nitrogen ratio (C/N) and organic matter content in the vermicompost. The addition of MM resulted in an increase in the pH, CEC, and surface area but a decrease in the C/N of the vermicompost. X-ray diffraction analysis showed that the addition of MM increased the contents of quartz, CaCO3, CaO and MgO in the vermicompost. Fourier transform infrared spectroscopy analysis indicated that comparatively less carbohydrates, lipids and polysaccharides and more aromatic compounds existed in the vermicompost, and the addition of MM increased the number of Me-O groups. Pot experiments showed that the application of vermicompost from cow dung and mineral vermireactors significantly promoted the growth of celery cabbage and reduced the Pb content in its edible parts and the Pb bioavailability in soil. Thus, it is possible to use cow dung and mineral vermireactors to optimize the properties of vermicompost for its use as a soil amendment to remediate Pb contamination.

Changes in land management and climate alter vegetation dynamics, but the determinants of vegetation changes often remain elusive, especially in global drylands. Here we assess the determinants of grassland greenness on the Mongolian Plateau, one of the world's largest grassland biomes, which covers Mongolia and the province of Inner Mongolia in China. We use spatial panel regressions to quantify the impact of precipitation, temperature, radiation, and the intensity of livestock grazing on the normalized difference vegetation indices (NDVI) during the growing seasons from 1982 to 2015 at the county level. The results suggest that the Mongolian Plateau experienced vegetation greening from 1982 to 2015. Precipitation and animal density were the most influential factors contributing to higher NDVI on the grasslands of Inner Mongolia and Mongolia. Our results highlight the dominant effect of climate variability, and especially of the precipitation variability, on the grassland greenness in Mongolian drylands. The findings challenge the common belief that higher grazing pressure is the key driver for land degradation. The analysis exemplifies how representative wall‐to‐wall results for large areas can be attained from exploring space–time data and adds empirical insights to the puzzling relationship between grazing intensity and vegetation growth in dryland areas., European Union's Framework Programme for Research and Innovation ‐ Horizon 2020 (2014‐2020), Alexander von Humboldt Foundation of Germany

Drought has become a major threat to local sustainable development in dryland Asia, one of the largest grassland ecosystems in the world. However, empirical‐ and science‐based evidence regarding the extent of drought changes and the future trends of these changes in dryland Asia is variable and incomplete. Here, we first investigate the historical variations in drought conditions in dryland Asia, as measured by the drought intensity and arid area, using three widely used drought indices (the Palmer Drought Severity Index, the Standardized Precipitation Index, and the Standardized Precipitation Evapotranspiration Index). Then, we use Bayesian model averaging to reproduce the future drought conditions under two representative concentration pathways (RCP2.6 and RCP4.5) from the Coupled Model Intercomparison Project Phase 5 Earth system models. The Palmer Drought Severity Index, Standardized Precipitation Index, and Standardized Precipitation Evapotranspiration Index illustrate that dryland Asia has experienced an overall drying trend and an expansion of arid areas over the past 100 years (1901–2016). Both temperature and precipitation are projected to increase under both the 1.5 and 2.0 °C warming scenarios compared with the values from the reference period (1986–2005). The projected drought conditions in the 1.5 and 2.0 °C warming scenarios will worsen, especially across Kazakhstan and Northwest China. We found that the drought conditions under the 2.0 °C warming conditions will not be as severe as those under the 1.5 °C warming conditions due to the mitigating effect of the projected precipitation increase under RCP4.5. These results call for short‐term and long‐term mitigation and adaptation measurements for drought events in dryland Asia.

In recent years, flash floods and urban waterlogging have become a widespread phenomenon in Fuzhou, which pose a serious threat to people’s lives and property. The primary disaster-causing factors include the intensity and duration of rainfall. Therefore, this article analyzes the characteristics, causes of rainfall, and the existing problems of the two disasters in Fuzhou. The main conclusions are as follows: (1) The rainfall in Fuzhou is concentrated in March to September, with high rainfall intensity and rainfall amounts, and frequent extreme rainfall events combined with high rainfall intensity in flash flood-prone areas are higher than that in the plains area. (2) Precipitation, geographical conditions, and urban construction mainly caused the two major disasters and are weak in technology and management. Therefore, it is necessary to adhere to both the structural measures and non-structural measures to coordinate the relationship between people and floods, to strengthen the research on the mechanisms of precipitation, and to forecast and provide early warning of flash floods and urban waterlogging, all of which can provide reference for the defensive disasters in mountainous coastal cities.

The warming climate has rapidly altered vegetation growth in drylands, and consequently, has put great pressure on sustainable livelihoods. Various datasets have been applied from local to global scale to study vegetation dynamics and there is a lack of solid comparison among multiple datasets. Note that vegetation growth might shift over time and the greening and browning components over a long-time span might be masked by a linear trend. Here, we aim to monitor the long-term and nonlinear dynamics in vegetation greenness for Inner Mongolia (an important part of dryland Asia). As a useful tool that indicates vegetation greenness, NDVI (Normalized Difference Vegetation Index) and LAI (Leaf Area Index) integrals derived from the GIMMS (Global Inventory Modelling and Mapping Studies) NDVI3g and the GIMMS LAI3g products are applied. During the period of 1982-2016, NDVI/LAI integrals have an overall acceptable consistency in characterizing the trends of vegetation greenness, with NDVI large/small integrals and LAI large/small integrals increase at a rate of 0.96, 1.72, 2.23, and 3.13 per decade, respectively. Inner Mongolia experienced a noticeable greening process (71% and 82% greening area in NDVI large/small integrals, 67% and 73% greening area in LAI large/small integrals), despite the fragmentally distributed browning trends in eastern and partial northern Inner Mongolia. As inferred from nonlinear trend analysis, we found the greening process is still prevalent. The browning of eastern Inner Mongolia under the linear analysis was actually transferring from browning to greening, while the greening trend in northern Inner Mongolia was changing to browning. Increased occurrences in the frequency of breakpoints after 1999 suggest that previously stable vegetation ecology is more sensitive to external disturbances such as altered climatic impact and anthropogenic intervention.

Cadmium (Cd) contamination has become serious in soil and in situ stabilization technology has been widely used for heavy metal remediation. A field study was conducted to determine the effect of amendments with the doses of 3 kg/m2, including single vermicompost (A1), a 95% vermicompost mixed with 5% shell powder composite (A2) and a 95% vermicompost mixed with 5% modified shell powder composite (A3), on the Cd bioavailability, enzyme activity and bacterial community in soil, and the experiment was conducted with lettuce (Lactuca sativa L.) grown in a Cd-contaminated farmland soil. The results showed that the application of amendments increased the pH, cation exchange capacity (CEC), organic matter (OM), available nutrients, catalase (S-CAT), invertase (S-SC) and urease (S-UE) activities in soil, while significantly reduced the Cd bioavailability with the lowest Cd bioavailability being observed in the soil with A3 application. The soil bacterial richness and diversity increased after amendments application, and the bacterial community was characterized by an increase in metal-tolerant bacteria but a decrease in Proteobacteria, Acidobacteria and Gemmatimonadetes. In addition, the application of amendments significantly improved the growth of lettuce (Lactuca sativa L.) and inhibited Cd accumulation in its edible parts, especially, the Cd content in lettuce (Lactuca sativa L.) grown in soil with A3 application was below the limit of the National Food Safety Standard of China (maximum level ≤ 0.2 mg/kg). Thus, composite amendment obtained from vermicompost mixed with modified shell powder can be used as potential remediation material in Cd-contaminated soil. Capsule Composite amendment obtained from vermicompost and modified shell powder had good effects on remediation of Cd-contaminated soil.

Through decreasing inter-cell interferences, CoMP (Coordinated Multi-Point) can enhance system capacity and spectral efficiency of cell-edge users significantly. BSs (Base stations) are the front-end accesses of CoMP and their planning influences the overall performance of the system directly. Different from the traditional cellular network, the coverage of BSs in CoMP always overlaps with each other to some degree. In order to investigate the BSs planning for CoMP, this paper builds two optimization models to obtain the location and the number of the BSs. A joint optimization algorithm is proposed to solve models, in which the methodologies of mesh adaptive direct search and successive elimination have been used. Numerical results show that the proposed models can effectively reduce the total transmission power and the number of BSs without losing the quality of service for users, which verifies the effectiveness of the proposed algorithms and the inherent advantage of CoMP.

In this study, the scaling behaviors of precipitation records over southern China are investigated by using the detrended fluctuation analysis (DFA) method. It is found that the precipitation records over southern China exhibit relatively weak long-term correlation characteristics. The scaling exponents in coastal areas are close to 0.6 showing long-term correlation while in inland areas, uncorrelation can be found with the scaling exponents close to 0.5. Based on the long-term correlation characteristics of the observed precipitation records, the performance of the Community Earth System Model (CESM1) in simulating precipitation over southern China is evaluated and the results show that the CESM1 can simulate the internal dynamics characteristics of precipitation series in southern China. As indicated by the DFA results of simulated precipitation data from CESM1, the long-term correlation of precipitation records during the late-21st century (2071–2100) will increase in the Huai river basin under the RCP8.5 simulation scenario in summer and decrease in most regions of southern China under both the RCP8.5 and RCP8.5_FixA scenarios in comparison with the present condition (1987–2016). Additionally, the differences of precipitation scaling exponents between the RCP8.5 and RCP8.5_FixA simulation scenarios further indicate that the future reduced aerosols emissions will contribute to strengthening the long-term correlation of precipitation records in the Huai river basin in summer. Compared to present condition, the precipitation scaling exponents will increase by more than 0.1 during the late-21st century.

The development of animal husbandry in China is facing enormous pressure from increasing demand of meat consumption, climate change, degrading grassland, and changing national policies. This paper presents the latest findings from an anthropological field investigation interviewing local herders, traders, and local officials from farming–pastoral ecotone in Inner Mongolia and shed lights on how locals have adapted their lives to climate change and the new national husbandry policies of the twenty-first century. Based on the anthropological interviews, we discussed the future opportunities and challenges of animal husbandry development in farming–pastoral ecotone. Results suggested that national ecological conservation policies and meat price have much larger impacts on animal husbandry than climate change, as perceived by locals. Family Fencing Policy, a relatively new policy aiming to avoid overgrazing and restore vegetation, was neither well accepted nor well implemented by the local herders. This is partially explained by the poor fencing technology, insufficient support facilities, as well as the high costs and low-profit margins in the animal husbandry. We conclude by suggesting that pastoralism in Northern China may greatly benefit from the development of rural cooperatives and active participation of locals in policy designing and implementation.

International research has focused more attention on arid and semiarid regions in recent years, as climate change has already had adverse impacts on grasslands and local households in the Mongolian plateau. Based on meteorological data, GIMMS AVHRR NDVI3g data, and livestock records, through statistical analysis, a significantly strong warming trend and a slightly decreasing trend in precipitation were ascertained in this region. Precipitation patterns are shifting, and intensifying, extreme events, such as droughts and dzud (extremely harsh winters characterized by heavy snow and low temperature), are a major threat to vegetation growth and animal husbandry development. Following a comparative analysis approach, we explored how the vegetation and animal husbandry response to climate change and extreme weather differ between Inner Mongolia and Mongolia. We found that vegetation growth generally decreased after the mid-1990s, but began to recover from 2001 over the entire region. The agricultural intensification level is higher in Inner Mongolia than in Mongolia, and residents in Inner Mongolia have a greater awareness of unexpected disasters than those in Mongolia. To deal with these challenges, this region warrants further study on how climate extremes will impact on regional animal husbandry and local social economics on the arid and semiarid regions. This could have implications for the international community, local government, local residents, and future scientific activities in this space.

Since the late 1970s, the Chinese government has implemented massive afforestation projects to address grievous environmental disasters, protect human health and provide long-term environmental security. Having a better understanding of the total carbon sink from the afforestation projects is fundamental to assess its global carbon benefit. Here, the sequestered carbon stock based on Chinese national forest inventory data is calculated by using three comparable volume-derived biomass models. Results show that the carbon sink contribution from these Chinese afforestation projects was 1.02 Pg C by the end of 2008 and 0.79 Pg C on average from 1981 to 2008 with a cumulative rate of 0.028 Pg C/a, which corresponds to 2 % of the total industrial carbon emissions from China during the same period. The financial value of carbon sequestration from these projects can be estimated by its value in carbon taxes of Finland and is potentially 190 billion RMB from 1981 to 2008, which is 43.4 % of the original investment. Hence although China’s afforestation projects make only modest contributions to offsetting industrial growth in carbon, the carbon sequestered, if valued according to some markets, is a significant fraction of the total project costs.

Dry Land Asia is the largest arid and semi-arid region in the northern hemisphere that suffers from land desertification. Over the period 1982–2011, there were both overall improvement and regional degeneration in the vegetation NDVI. We analyze future climate changes in these area using two ensemble-average methods from CMIP5 data. Bayesian Model Averaging shows a better capability to represent the future climate and less uncertainty represented by the 22-model ensemble than does the Simple Model Average. From 2006 to 2100, the average growing season temperature value will increase by 2.9 °C, from 14.4 °C to 17.3 °C under three climate scenarios (RCP 26, RCP 45 and RCP 85). We then conduct multiple regression analysis between climate changes compiled from the Climate Research Unit database and vegetation greenness from the GIMMS NDVI3g dataset. There is a general acceleration in the desertification trend under the RCP 85 scenario in middle and northern part of Middle Asia, northwestern China except Xinjiang and the Mongolian Plateau (except the middle part). The RCP 85 scenario shows a more severe desertification trend than does RCP 26. Desertification in dry land Asia, particularly in the regions highlighted in this study, calls for further investigation into climate change impacts and adaptations.

The Mongolian Plateau (MP) steppe is one of the largest steppe environments in the world. To monitor the terrestrial vegetation dynamics on the MP and to ascertain what the driving forces, this study examined the vegetation dynamics in Republic of Mongolia (M) and the Inner Mongolia Autonomous Region (IM) of China from the period 1982 to 2011, based on the satellite-derived GIMMS NDVI3g (Normalized Difference Vegetation Index) data across three biomes (desert, grassland and forest). The results are as followed: (1) Vegetation coverage in IM was generally greater than that in M. Before 2002, time series of NDVI over the MP increased at an average rate of 0.05% yr −1 . Additionally, after 2002, the NDVI increased at a rate of 0.21% yr −1 . From 1982 to 2011, the area of IM and M with positive anomalies in the NDVI increased at a separate rate of 1.82% yr −1 and 1.76% yr −1 , respectively. (2) At the biome scale, the inter-annual forest NDVI variation in IM and desert NDVI for the entire MP had a significant increasing trend (0.06% yr −1 and 0.04% yr −1 , respectively). (3) Climate forcing was a dominant controlling factor affecting the vegetation, and the anthropogenic behavior exhibited no significant value in the whole region. However, overgrazing was the most important reason for the regional degradation, particularly in IM. (4) In the future, the forest biome will go to recovery, whereas both the grassland and desert biomes are predicted to degrade continuously.

Consumption of fossil fuel resources leads to global warming and climate change. Apart from the negative impact of greenhouse gases on the climate, the increasing emission of anthropogenic heat from energy consumption also brings significant impacts on urban ecosystems and the surface energy balance. The objective of this work is to develop a new method of estimating the global anthropogenic heat budget and validate it on the global scale with a high precision and resolution dataset. A statistical algorithm was applied to estimate the annual mean anthropogenic heat (AH-DMSP) from 1992 to 2010 at 1×1 km2 spatial resolution for the entire planet. AH-DMSP was validated for both provincial and city scales, and results indicate that our dataset performs well at both scales. Compared with other global anthropogenic heat datasets, the AH-DMSP has a higher precision and finer spatial distribution. Although there are some limitations, the AH-DMSP could provide reliable, multi-scale anthropogenic heat information, which could be used for further research on regional or global climate change and urban ecosystems.

Connected vehicles have received much attention in recent years due to their significant societal benefit and commercial value. However, a suitable channel model for vehicle-to-vehicle (V2V) communications is difficult to build due to the dynamic communication environment. In this paper, a three-dimensional (3D) geometrical propagation model that includes line-of-sight (LoS), single bounced (SB), and multiple bounced (MB) rays is proposed. Each of multiple scatterers in the model is moving with a random velocity in a random direction. Based on the geometrical propagation model, a generalized 3D reference model for narrowband multiple-input-multiple-output (MIMO) V2V multipath fading channels is developed. The corresponding space-time correlation functions (ST-CFs), time correlation functions (T-CFs), and space correlation functions (S-CFs) are analytically investigated and numerically simulated in terms of various factors. Several notable ST-CFs for V2V and fixed-to-mobile (F2M) communications become the special cases of ST-CFs of the proposed model by adjusting the corresponding channel parameters. Finally, the theoretical results of the space-Doppler power spectral density (SD-PSD) are compared with the available measured data. The close agreements between the theoretical and measured SD-PSD curves confirm the utility and generality of the proposed model.

Arid and semi-arid regions are highly sensitive to environmental extremes, directly affecting the economic structures and development of human societies. Climate change and human activities are the major factors of vegetation changes in these regions. This study analyzes the roles of these factors of vegetation changes within forest, grassland and desert biomes across Inner Mongolia autonomous region (IM) in China and forecasts the future vegetation dynamics in this region. Based on data from 49 meteorological stations from 1961 to 2012 and the SPOT VEG Normalized Difference Vegetation Index (NDVI) satellite data from 1998 to 2012, we analyze the vegetation coverage patterns, variations and its associating dynamic responses to climate change using the methods of Maximum Value Composition, correlation analysis, fluctuation analysis and the Hurst index. The results show that NDVI patterns in IM were determined by geographical longitude and latitude. The central and eastern portion of IM encompasses a wide area with high vegetation coverage, particularly in Hulun Buir and Xilin Gol. Over the past 15 years, the NDVI has declined in the central portion of Xilin Gol, while vegetation recovery from past degradation was evident in the desert and forest regions. Our results also demonstrate that precipitation was the major driver of vegetation growth other than temperature. However, most of the vegetation in this region is likely to show strong, sustainable growth in the future.

This study evaluates the performances of three global satellite datasets (Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS) and Satellite pour l’ observation de la Terre (SPOT) of the Mongolian Plateau, where in situ observation is insufficient to assess vegetation dynamics on terrestrial systems. We give a comprehensive assessment of the historical changes in vegetation dynamics by using comparative and correlation methods on the three archives using two indices: the growing season’s Normalized Difference Vegetation Index (NDVI) and the Start of the Season Index (SOS). The main findings are: (1) MODIS and SPOT have generally better comparability and consistency in the spatial-temporal trends of NDVI and SOS than AVHRR in this area; (2) all the three archives exhibit better consistency in Inner Mongolia than in Mongolia; (3) integration data analysis of AVHRR (1982–1997) and SPOT (1998–2012) shows that the dynamics of vegetation growth has three distinct phases: enhanced before 1994; a flatter/slightly decreasing trend before 2001; and, then, a rapid recovery between 2001 and 2012 with remarkable spatial heterogeneity, with Inner Mongolia experiencing a significant greening in vegetation NDVI compared with no obvious changes in Mongolia; (4) the temporal average SOS showed no significant “earlier spring” onset during the past 31 years, on the middle and northern Mongolian Plateau.

China's land use has undergone many changes over the past 300 years due to the significant transformations caused by natural and human factors and their impact on regional climate and the environment. This comprehensive review of recent state-of-the-art studies of China's land-use changes during that period concentrates on cropland, forest, grassland and urban areas. While most small-scale studies have reconstructed information from historical archive data and focused on a specific time period, large-scale studies have tended to rely on inverse modeling techniques to interpret land-use change dynamics based on remote-sensing data for example, the global land-use products of the History Database of the Global Environment (HYDE) and Center for Sustainability and the Global Environment (SAGE) datasets. All studies have shown that the cropland areas in China increased between 1700 and 1950, although they indicate different magnitudes and rates. A decrease in forest coverage was also reported in all studies. Little information was available on urban and grassland areas over the same period. Rapid urbanization in China has been particularly evident in the past 50 years. Meanwhile, spatially explicit reconstructions of historical land-use change in China since 1700 remain highly uncertain due to the lack of reliable data. Extensive work on primary data collection is required, including land-use records and drivers for future change.

The spectrum allocation for cognitive radio networks (CRNs) has received considerable studies under the assumption that the bandwidth of spectrum holes is static. However, in practice, the bandwidth of spectrum holes is time-varied due to primary user/secondary user (PU/SU) activity and mobility, which result in non-determinacy. This paper studies the spectrum allocation for CRNs with non-deterministic bandwidth of spectrum holes. We present a novel probability density function (PDF) model through order statistic to describe the non-deterministic bandwidth of spectrum holes and provide a bound to approximate it. After that, a statistical spectrum allocation model based on stochastic multiple knapsack problem (MKP) is established for spectrum allocation with non-deterministic bandwidth of spectrum holes. To reduce the computational complexity, we transform this stochastic programming probleminto a constant MKP though exploiting the properties of cumulative distribution function (CDF), which can be solved via MTHG algorithm by using auxiliary variable. Simulation results illustrate that the proposed statistical spectrum allocation algorithm can achieve better performances compared to the existing algorithms when the bandwidth of spectrum holes istime-varied.

Li 2 FeSiO 4 /C composites with in situ carbon coating were synthesized via sol–gel method based on acid-catalyzed hydrolysis/condensation of tetraethoxysilane (TEOS) with sucrose and l -ascorbic acid as carbon additives, respectively. As-obtained Li 2 FeSiO 4 /C composites prepared with l -ascorbic acid as a carbon additive are composed of nanoparticulate Li 2 FeSiO 4 in an intimate contact with a continuous thin layer of residual carbon and exhibit large specific surface area up to 395.7 m 2 g −1 . The results indicate that structure of the residual carbon is graphene-rich with obviously lower disordered/graphene (D/G) ratio. These as-obtained Li 2 FeSiO 4 /C composites exhibit first discharge capacity of 135.3 mAh g −1 at C/16 and perform cycling stability, which are superior to those of Li 2 FeSiO 4 /C composites synthesized with sucrose as a carbon additive.

Understanding the processes of historical land-use change is crucial to the research of global environmental sustainability. Here we examine and attempt to disentangle the evolutionary interactions between land-use change and its underlying causes through a historical lens. We compiled and synthesized historical land-use change and various biophysical, political, socioeconomic, and technical datasets, from the Qing dynasty to modern China. The analysis reveals a clear transition period between the 1950s and the 1980s. Before the 1950s, cropland expanded while forested land diminished, which was also accompanied by increasing population; after the 1980s land-use change exhibited new characteristics: changes in cropland, and decoupling of forest from population as a result of agricultural intensification and globalization. Chinese political policies also played an important and complex role, especially during the 1950s–1980s transition periods. Overall, climate change plays an indirect but fundamental role in the dynamics of land use via a series of various cascading effects such as shrinking agricultural production proceeding to population collapse and outbreaks of war. The expected continuation of agricultural intensification this century should be able to support increasing domestic demand for richer diets, but may not be compatible with long-term environmental sustainability.

As an important knowledge, data provenance has been used in a variety of applications, such as information integration, scientific databases and Web intelligence. Capturing data provenance during data transformations is of great significance for the improvement of the service quality. So the issues of representing and deducing data provenance have received more and more attentions. This work provides a formal provenance representation framework for data in XQuery views. Firstly, based on existing relational provenance semirings, a novel provenance bi-semiring structure K for XML data is introduced, and a K-Tree model is proposed, in which all nodes are annotated with elements from K. Then, the generalized algebraic query evaluations on K-Tree are presented, and the representations and computations for Where-provenance and How-provenance semantics are given. Finally, the application analysis for provenance bi-semiring are provided, which demonstrates that the proposed provenance framework in the paper is a general representation structure which is widely used in the field of granular computing.

In order to grasp the spatial and dynamic changes of mountain bamboo resources, this study uses the 2007 forestry investigation sub-compartment diagram of Shuncang, Fujian province, two-period TM images, DEM and other data in 1998 and 2007 to extract information of bamboo forest through Remote sensing and Geographic Information technology, create spatial distribution map of bamboo forest and make overlay analysis of it with topographic factors grade map, so as to research the topography differentiation characteristics of spatial distribution and dynamic change of bamboo forest. The results show that the bamboo forest in Shuncang is mainly distributed in the semi-sunny slope and semi-cloudy slope with where are at an elevation of 1200m below with a slope of 25 degrees below, the mountain bamboo forest at the elevation of 1200m below accounts for 99.89% of the total bamboo forest area, the proportion of bamboo forest with a slope of 25 degrees below is90.39%, while the proportion of bamboo forest with a slope of 35 above is less than 3%; the proportion of bamboo forest in semi-sunny slope and semi-cloudy slope is 56.98%; for almost 20 years, the bamboo forest resources in this county are improving rapidly, increase, decrease and unchange, this three kinds of variation types trend to increase firstly and then decrease with the changes of slope direction and aspect, while with the increase of elevation, the types of increase and unchange trend to increase firstly and then decrease, the decrease type is decreasing gradually.

Li2FeSiO4/C composites are synthesized by a sol—gel method based on acid-catalyzed hydrolysis/condensation of tetraethoxysilane using sucrose or L-ascorbic acid as carbon additive and LiOAc and Fe(NO3)3 as metal sources (autoclave, 120 °C, 20 h).